1403 33 6 146 97

مقاله علمی – پژوهشی:‌ تأثیر برخی شاخص‌های تغییر اقلیم بر توسعه ظرفیت پرورش قزل‌آلای رنگین‌کمان حوضه رودخانه بشار (استان کهگیلویه و بویراحمد) Effect of some climate change parameters on the development of rainbow trout farming capacity in the Bashar River basin (Kohgiluyeh and Boyerahmad Province) 1 1 استان کهگیلویه و بویراحمد در سال 1402 با تولید23000 تن ماهی قزل‌‌آلای رنگین کمان در کشور از جایگاه سوم برخوردار بوده است. عمده تولید آبزیان این استان در حوضه رودخانه بشار صورت می‌‌گیرد. در این تحقیق، ضمن بررسی میانگین آمار دما، بارندگی سالانه و دبی رودخانه بشار در این حوضه طی یک دوره دراز مدت، تغییرات مهم‌ترین پدیده‌های متأثر از اقلیم با نتایج مطالعات نرم افزاری ارائه شواهد تغییر اقلیم در حوضه آبریز مقایسه شد. همچنین تأثیر تغییرات مذکور بر پایداری و توسعه تولید قزل‌‌الای رنگین‌‌کمان مد نظر قرار گرفت. یافته‌ها حاکی از افزایش میانگین دمای سالانه و کاهش بارندگی سالانه (18 درصد) در بلند مدت در حوضه بود به‌طوری‌که در ده ساله ابتدای دوره مورد بررسی میانگین بارش 287 ± 892 میلی‌متر و در هشت سال انتهایی به 275 ± 728 میلی‌متر (شکل 5) بوده ولی فاقد تفاوت معنی‌داری با هم بودند (05/0<P). کاهش میانگین دبی رودخانه در ده سال اخیر نسبت به 40 سال قبل از آن به میزان 30 درصد بوده است (05/0>P). یافته‌های حاصل از مطالعات نرم افزاری نشان داد که طی قرن آینده، افزایش درجه حرارت و کاهش بارندگی وجود داشته و کاهش بارش در نیمه دوم قرن بیشتر از نیمه اول آن است. بروز سیلاب و گل آلودگی آب سبب خسارت به مزارع با منبع آبی رودخانه شده و طی 4 سال اخیر 3 بار منجر به تلفات بیش از هزار تن ماهی شده است. احداث زه‌‌کش در حاشیه رودخانه با رعایت نکات فنی و ایمنی تاسیسات در مقابل سیل جهت احداث مزارع پرورش ماهی قزل‌‌الای رنگین‌‌کمان ضروری است. همچنین با افزایش تولید در واحد سطح با استفاده از مکانیزاسیون برگشت آب و فیلتراسیون در مزارع موجود می‌توان به توسعه آبزی‌پروری در جریان اصلی رودخانه بشار در پایین‌دست در محدوده دوروهان (بالاتر از ایستگاه 4) تا انتهای حوزه آبریز در استان امیدوار بود. علاوه‌براین، پیشنهاد می‌‌شود که صدور مجوزهای جدید به‌تدریج طی 10-5 سال تنها با بررسی بازخورد بهره‌برداری از مجوزهای اولیه صادره، انجام شود. 2 Introduction Kohgiluyeh and Boyerahmad province ranked third in the country in 2023 with a production of 23,000 tons of rainbow trout (Qurbanzadeh and Sedghpour, 2023). The majority of this production takes placed in the Beshar river basin as one of the main branches of the Karun river (Rastiannasab et al., 2023). Climate change has been recognized as a major environmental crisis and concerned by the World Meteorological Organization (Kalbali et al., 2021). Climate change leads to changes in the amounts and patterns of precipitation and temperature at the basin (Sarkar and Chicholikar, 2017). In Iran, precipitation is one of the basic variables for evaluating the potentially available water resources, but its temporal and spatial distribution is very heterogeneous, therefore the distribution of water resources in the country is not uniform (Hassan et al., 2014). For this reason, temporal variability of precipitation  has great importance in assessing the available water resources of watersheds and studying the relative availability of water resources at local and regional scales (Sha et al., 2019). Despite the few studies conducted to investigate  the most important phenomena affected by climate change and impressive on water resources in Kohgiluyeh and Boyerahmad province, many applicants insist on issuing permits to build new farms. In this study, it is attempted to examine data of the most important meteorological stations in the watershed and the flow statistics of the Beshar river over a long period to compare the obtained results with the findings of software studies conducted to providing evidence of climate change in the watershed, to explain the impact of the weather changes on aquaculture activities, the production of freshwater fish in this area and the sustainability of this industry in the future. Methodology Average temperature and rainfall data were collected based on the average air temperature and rainfall from the Yasouj Synoptic Meteorological Station in the center of the studied basin in different months of the year and annual average over a 35-year period ended 2023, the flow statistics of the Beshar river over a long period to compare the mentioned statistics with the average of  them in the last ten years were used, Data on air temperature, precipitation, and river flow in the last 10 years were calculated and reported as monthly averages and standard deviations over a long period. Data analysis was performed using independent samples t-test using SPSS version 24 statistical software package in case of homogeneity of variance, and non-parametric Mann-Whitney U test was used in case of non-normality of data. Results The findings indicated an increase in the average annual temperature and a decrease in annual rainfall (18%) in the long term in the basin (Fig. 1) so that the average rainfall in the first ten years of the period was (892±287 mm) and the last eight years (728±275 mm) which had no significant difference (P<0.05). The decrease of the average discharge of the river in the last ten years compared to the previous 40 years was 30% (P<0.05). Figure 1: The location of the Beshar river flow monitoring stations, the river's catchment area regarding to the Persian Gulf watershed The results of the data analysis indicated a significant decrease in precipitation in the winter season compared to previous years (P<0.05), so that most of the decrease in precipitation in the last ten years is observed in the winter season (Fig. 2). Figure 2: Ten- year average annual air temperature of Yasouj meteorological station in the basin of Beshar River The Qalat station (station1) is located at the beginning of the watershed, within the village of Qalat, in the upper part of the river. Based on the data analysis, the average river discharge at the Qalat station has decreased by nearly 25 percent in the last ten years compared to the long term period (P<0.05). Patavah station (station 4) is considered the last hydrometric station of the Bashar river basin and receives water from all branches and after a distance in the Darb Qalat area, the River basin is ended. The decrease in the average flow in the last ten years compared to the previous 40 years in Patavah station was 35 percent (P<0.05).The river discharge in summer was lower than the other seasons. Discussion and conclusion According to the results, the decrease in flow of Beshar river is due to the decrease in rainfall in recent years compared to the long-term period, by 25 to 35 percent in the upstream and downstream river areas, respectively. Therefore, it is expected that the decrease in winter precipitation in the form of snow and rain in recent years has caused the decrease in the flow of river lately. The findings of the software studies showed that during this century, it will be an increase in temperature and a decrease in precipitation, and the decrease in precipitation in the second half of the century is more than the first half (Panahi et al., 2022). In addition to reducing the flow, the occurrence of floods and water turbidity resulted of climate change (Chun et al., 2013) have directly caused damage to the farms using the river water (Rastiannasab, 1998) and  effective in 3 times loss of more than a thousand tons of fish in the last 4 years. It is necessary to build a drainage system on the river bank to supply water as technical and safety facilities against floods in onset of rainbow trout fish farms construction. Apart of increasing the production per unit area by using the mechanization, filtration and reuse of drained out water in the active farms, we can be hoped for the development of aquaculture in the main flow of the Bashar River in downstream, from the Durohan area (near station 4) to the end of the catchment area in the province via issue new licenses gradually over 5 to 10 years and review the feedback of the initial licenses issued. Conflict of Interest We wish to confirm that there are no known conflicts of interest associated with this study. Acknowledgements This article is a part of the final report of the research project approved by the Iranian Fisheries Science Research Institute (IFSRI) from the fund of Kohgiluyeh and Boyerahmad Agriculture- Jahad Organization. We wish to express our thanks to Dr. Motamedi as the its chairman. 1 13 2023/12/23 1402/10/2 2025/02/28 1403/12/10 ابوالحسن راستیان نسب Abulhassan Rastiannasab مؤسسه تحقیقات علوم شیلاتی کشور، مرکز تحقیقات ژنتیک و اصلاح نژاد ماهیان سردابی شهید مطهری یاسوج، سازمان تحقیقات، آموزش و ترویج کشاورزی، یاسوج، ایران Iran rastian1920@yahoo.com محمود بهمنی mahmood Bahmani مؤسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، تهران، ایران Iran mahmoudbahmani@gmail.com سید عبدالحمید حسینی seyed abdolhamid hosseini مؤسسه تحقیقات علوم شیلاتی کشور، مرکز تحقیقات ژنتیک و اصلاح نژاد ماهیان سردابی شهید مطهری یاسوج، سازمان تحقیقات، آموزش و ترویج کشاورزی، یاسوج، ایران Iran hoseiniabdolhamid@gmail.com محمدمیثم صلاحی اردکانی mohammad meysam salahi ardakani مؤسسه تحقیقات علوم شیلاتی کشور، مرکز تحقیقات ژنتیک و اصلاح نژاد ماهیان سردابی شهید مطهری یاسوج، سازمان تحقیقات، آموزش و ترویج کشاورزی، یاسوج، ایران Iran mmsalahi.a@gmail.com اسماعیل کاظمی esmaeil kazemi مؤسسه تحقیقات علوم شیلاتی کشور، مرکز تحقیقات ژنتیک و اصلاح نژاد ماهیان سردابی شهید مطهری یاسوج، سازمان تحقیقات، آموزش و ترویج کشاورزی، یاسوج، ایران Iran esmaeil.kazemi.1986@gmail.com Beshar river Climate change Aquaculture development Fish farming Rainbow trout رودخانه بشار تغییر اقلیم توسعه آبزی‌پروری پرورش ماهی قزل‌الای رنگین‌کمان Abdullah, N. and Jain, S., 2020. Multi-index summer flow regime characterization to inform environmental flow contexts, A New England case study. Journal of Ecological Indicators, 111:1-15. DOI: 10.1016/j.ecolind.2019.106008.##Chun, K. P., Wheater, H. S., Nazemi, A. and Khaliq, M.N., 2013. Precipitation downscaling in Canadian Prairie Provinces using the LARS-WG and GLM approaches. Canadian Water Resources, 38(4):311-332. DOI: 10.1080/07011784.2013.830368.##Gholizadeh, M. and ‌Heydari, O., 2020. Evaluation of Gorganrood river water quality based on surface water quality indicators in Gonbad Kavous. Iranian Journal of Health and Environment, 13(1):33-48. [In Persian]##Ghorbani, Kh., Sohrabian, E., Salarijazi, M. and Abdolhoseini, M., 2016. Prediction of climate change impact on monthly river discharge trend using IHACRES hydrological model (case study: Galikesh watershed). Journal of Water and Soil Resources Conservation, (4):19-34. DOI: WSRCJ-1512-10446.##Hassan, Z., Shamsudin, S. and Harun, S., 2014. Application of SDSM and LARS-WG for simulating and downscaling of rainfall and temperature. Theoretical and Applied Climatology, 116(1–2): 243–257. DOI: 10.1007/s00704-013-0951-8.##Hosseini S.A., Rastiannasab A., Salahi Ardakani M., Gandomkar F. and Kazemi E, 2023. Feasibility of aquaculture development of sturgeon farming in Kheirabad river of Gachsaran city based on water physicochemical indicators and climatic data. Iranian Scientific Fisheries Journal, 32(5):63-77. DOI: 10.22092/ISFJ.2024.130714. [In Persian].##Kalbali, E., Ziaee, S., Mardani Najafabadi, M. and Zakerinia, M., 2021. Approaches to adapting to impacts of climate change in northern Iran: The application of a Hydrogy-Economics model. Journal of Cleaner Production, 280:321-349. DOI: 10.1016/j.jclepro.2020.124067.##Mohammadi, H., Khalili, R. and Mohammadi, S., 2021. Forecasting future temperature and precipitation under the effects of climate change using the LARS-WG climate generator (Case Study: South Zagros Region of Iran). Journal of Nivar, 45:137–153. DOI: 10.30467/nivar.2022.319565.1209##Panahi, H., Montaseri, H., Hekmatzadeh, A. and Khalili, R., 2022. Investigating the effect of climate change on temperature and precipitation using the LARS-WG model, case study: Beshar River Basin. Journal of Environmental Research and Technology, 7(12): 129-142. [In Persian]##Qurbanzadeh, R. and Sedghpour, S., 2023. Statistical yearbook organization Iranian fisheries 2018-2022. Planning and budget office, Organization Iranian fisheries, Gilan Picture Publication, Iran, 64p.##Rastiannasab, A., Pourang, N., Meysam Salahi Ardekani, M., Habibollah Gandomkar, Mahdave Jehanabad, J., Forouzad, M., kazemi E., Moradyan, S., Hossaeini, A. and Karimi, H., 2023. Assessment of Bashar River basin in Kohgiluyeh and Boyer-Ahmad province in order to develop aquaculture and to increase cold-water fish culture based on limnological studies. Iranian Fisheries Science Research Institute(IFSRI), Final project report, 72p. [In Persian]##Rastiannasab, A., Gafarii, H., Ghaedi, A., Nazari, S., mahmodi, R., Gandomkar, H., Hossaeini, A., Yazdanpanah, K., Bashti, T. and Radkhah, K., 2019. Assessment of some heavy metals concentrations in substrate sediments and muscle of farmed rainbow trout on the margin of Bashar River. Iranian Fisheries Science Research Institute(IFSRI), Final project report,pp.36. [In Persian].##Rastiannasab, A., 1998. Limnological study of Beshar river in Kohgiluyeh and Boyer Ahmad province. Master's thesis of fisheries. Tarbiat Modares University.pp.127. [In Persian]##Salahi Ardakani, M.M, Kazemi,E., Rastiannasab, A., Hoseini, S.A., Moradian, H. and Mahmodi, R., 2023. Evaluation of the capacity of Maron and Khairabad rivers for the development of tropical fish breeding in Kohgiluyeh and Boyerahmad provinces based on biological and non-biological indicators. Advanced Aquaculture Science Journal, 7: 33-40. [In Persian]##Sarkar, S. and Maity, R., 2020. Increase in probable maximum precipitation in a changing climate over India. Journal of Hydrology, 585:423-441. DOI: 10.1016/j.jhydrol.2020.124806##Sarkar, J. and Chicholikar, J.R., 2017. Future climate change scenario in hot semi-arid climate of Saurashtra, Gujarat by using statistical downscaling by LARS-WG model. Journal of Mausam, 68(4), 589–596. DOI:10.54302/mausam.v68i4.714##Sha, J., Li, X. and Wang, Z.L., 2019. Estimation of future climate change in cold weather areas with the LARS-WG model under CMIP5 scenarios. Theoretical and Applied Climatology, 137(3):1-13. DOI: 10.1007/s00704-019-02781-4##Thamo, T., 2017. Climate change in Western Australian agriculture: a bioeconomic and policy analysis. The University of Western Australia, Doctoral Thesis, Australia. 271 P. ##Zubaidi, S. L., Kot, P., Hashim, K., Alkhaddar, R., Abdellatif, M. and Muhsin, Y.R., 2019. Using LARS–WG model for prediction of temperature in Columbia City, USA. IOP Conference Series: Materials Science and Engineering, 584(1), 12026. DOI:10.1088/1757-899X/584/1/012026## ##

مقاله علمی – پژوهشی:‌ رتبه بندی عوامل مؤثر بر توسعه صادرات میگوی ایران به کشور چین Ranking of factors affecting the development of Iran's shrimp exports to China 1 1 هدف این مطالعه شناسایی ورتبه بندی عوامل مؤثر در توسعه صادرات میگوی ایران به کشور چین است. بدین منظور، در سال 1402 پرسشنامه‌ای شامل عوامل احتمالی مؤثر در توسعه‌ صادرات میگوی ایران به کشور چین در قالب طیف لیکرت (Likert scale) 5 درجه‌ای تهیه و بین صادرکنندگان میگوی ایران، خبرگان و مطلعین حوزه‌ شیلات توزیع شد. روش تحقیق این پژوهش کمی و از نوع توصیفی پیمایشی و روش نمونه‌گیری، نمونه‌گیری در دسترس بود. روش تهیه پرسشنامه به صورت آنلاین بود که در اختیار اعضای نمونه قرار گرفت. تحلیل داده‌ها با کمک نرم افزار SPSS انجام شد. نتایج حاصل از پژوهش نشان داد که دسترسی مناسب به خدمات بانکی بین‌المللی، محدودیت‌های انتقال پول برای خرید نهاده‌ها یا انتقال پول به داخل، ضعف برندسازی، پایین بودن توان رقابت صادرکنندگان ایرانی، نوسانات نرخ ارز، همسو نبودن استراتژی تولید و صادرات، محدود بودن ظرفیت و توانایی (مالی و اجرایی) صادرکنندگان، پایین بودن سطح دانش بازاریابی صادرکنندگان میگو، عدم حمایت مناسب و مؤثر نظام بانکی در تخصیص تسهیلات به تولید و صادرات و فقدان کنسرسیوم صادراتی، به‌ترتیب ده عامل مؤثر با بالاترین میزان تأثیر در صادرات میگو به کشور هستند. 2 Introduction The agricultural export sector plays a significant role in Iran's non-oil exports, particularly in food and agricultural products. These products are crucial for securing foreign currency and supporting the national economy. In 2022, Iran's agricultural product exports reached over 5.2 billion dollars, representing 9.77% of total non-oil exports. However, the sector remains highly reliant on imports, which amounted to around 17.8 billion dollars, highlighting the importance of domestic production growth and export development to achieve a positive trade balance. One of the key products in Iran's agricultural export portfolio is shrimp. According to Iran's Fisheries Statistical Report, shrimp exports in 2022 totaled over 37,000 tons, accounting for nearly 21% of the country's fishery exports. This generated over 600 million dollars in foreign currency, with shrimp contributing more than 180 million dollars. With total shrimp production in 2022 reaching 68,267 tons, more than 55% was exported, underscoring shrimp's importance as a major export product. China is one of the largest shrimp markets globally and has been a consistent top destination for Iran's shrimp exports. In 2021, China imported over 4 billion dollars worth of shrimp, and the demand for imports continued to rise in the first half of 2022, showing a growth of 25.8%. From 2017 to 2021, China consistently ranked as the primary destination for Iran’s shrimp, except for 2020 when the UAE took the lead. Recently, Russia has also emerged as a growing export market for Iran's shrimp, with exports to Russia surpassing 17 million tons in 2022. This research aims to rank the obstacles to expanding Iran's shrimp exports to China and provide recommendations for overcoming these challenges. Understanding the factors influencing this market is vital to enhancing Iran's shrimp export capacity and maintaining its competitive position in the global shrimp trade. Methodology Through the review of scientific sources, reports from relevant organizations, library studies, and interviews with experts from both government and private sectors, and exporters, 36 factors influencing the export of Iranian shrimp to China were identified, and a questionnaire was developed. The research variables were measured using the Likert scale, with respondents answering the questionnaire questions on a scale from 1 to 5, where 1 = very low, 2 = low, 3 = moderate, 4 = high, and 5 = very high. The overall framework of the questionnaire questions and each of the potential factors included in the questions were validated through interviews with experts and confirmed for content validity. The target population consisted of individuals who had significant experience in shrimp exports or had worked in the fisheries sector, in either executive, research, or production roles. The data collected from the questionnaires were analyzed using SPSS analytical software. The results were then evaluated, and based on the analysis; answers to the research questions were derived. Results A total of 53 participants completed the survey, with an average age of 62 years. The sample was predominantly male, as 92% of respondents were men, while only 8% were women. In terms of age distribution, 38% of participants were over 60 years old, which constituted the largest group, followed by 26% in the 51-60 age range. Regarding educational qualifications, 40% of respondents held a doctoral degree or higher, while 53% had at least a master's degree. This indicates a highly educated respondent pool with substantial expertise in the field of shrimp export. The majority of respondents (72%) had more than 20 years of experience in the shrimp and fisheries sector, indicating an experienced sample. Only 13% had less than 10 years of experience. Of the participants, 43% were involved in shrimp export, and 42% were engaged in shrimp processing. The sample also included experts from various subfields of the fisheries sector: 38% were fisheries experts, 19% were researchers, 34% were shrimp farmers, and 9% were involved in fishing. Many respondents were active in multiple areas of the shrimp industry. Data Analysis: The data collected using a 5-point Likert scale (ranging from 1 = very low to 5 = very high) were ordinal in nature, which necessitated the use of non-parametric tests. To ensure the validity of the statistical methods, the Kolmogorov-Smirnov test was applied to assess the normality of the data distribution. The results indicated that the data did not follow a normal distribution (p-value<0.05), supporting non-parametric methods for further analysis. Chi-Square Analysis: The Chi-square test was employed to explore the relationships between the identified barriers and export outcomes. The null hypothesis posited that no significant relationships existed between the variables while rejecting this hypothesis would indicate meaningful relationships. The Chi-square results revealed that 9 factors, including limited production capacity, poor product quality, lack of product diversity, and weak adherence to health standards in the destination country, did not show a significant relationship with export outcomes (p > 0.05). This suggests that these factors did not substantially affect the success of shrimp exports. However, 27 factors exhibited significant relationships with export outcomes (p-value < 0.05). These factors included limited access to international banking services, restrictions on money transfers for purchasing inputs, weak branding, low competitiveness of Iranian exporters in the Chinese market, fluctuations in exchange rates, misalignment between production and export strategies, limited financial and operational capacity of exporters, lack of marketing knowledge, lack of coordination between export-related agencies, absence of export consortiums in the Chinese market, and insufficient banking support for production and export financing. These variables were identified as the most pressing barriers to the growth of shrimp exports from Iran to China. Friedman Test: To evaluate the importance of each identified barrier, a Friedman test was conducted, ranking the barriers based on the respondents’ ratings. The null hypothesis assumed no differences in the rankings of the barriers, but the results indicated significant differences (p-value < 0.05), meaning the barriers were ranked differently by the participants. The rankings highlighted that the top challenges to shrimp exports were “Limited access to international banking services,” ranked first, followed by “Restrictions on money transfers for inputs and funds repatriation” in second place, and “Weak branding” in third. These were considered the most critical factors that needed to be addressed to improve export performance. Other important barriers included “Low competitiveness of Iranian exporters in China,” “Exchange rate fluctuations,” “Misalignment between production and export strategies,” and “Limited capacity and ability (financial and operational) of exporters.” Discussion and conclusions The study identified 27 significant factors influencing the development of shrimp exports to China, with marketing being the most impactful area, followed by banking, laws and regulations, transportation, production, and veterinary regulations. The top ten barriers included issues like limited access to international banking services, weak branding, low competitiveness of Iranian exporters, exchange rate fluctuations, misalignment between production and export strategies, and insufficient banking support. Previous studies, such as Heidarian (2011), also highlighted that increased production facilities and government support boost exports. However, access to financial resources did not significantly affect shrimp exports. Similarly, Ali Akbarzadeh Bidgoli (2018) found that domestic shrimp production, global shrimp prices, and farm area ratios significantly affected exports, while exchange rates did not. Norouzi (2019) emphasized the importance of factors like improved packaging, reducing exchange rate fluctuations, and expanding preferential tariffs to enhance export performances. The findings suggest that the Iranian government can play a key role by offering clear support to the aquaculture sector, attracting foreign investment, improving international relations, and reforming customs regulations. Additionally, addressing production costs, enhancing marketing knowledge, and establishing an export consortium can further improve export performance. Furthermore, implementing an efficient traceability system would help meet sanitary standards in China and improve overall export processes. The study advocates for a coordinated approach to addressing financial and operational challenges to boost shrimp exports. Conflict of interest The authors of this article have fully adhered to publication ethics, including avoiding plagiarism, misconduct, data fabrication, and duplicate submission and publication. There are no commercial interests associated with this work, and the authors have not received any financial compensation for submitting their manuscript. Acknowledgment We would like to express our sincere gratitude to the Iranian Fisheries Science Research Institute (IFSRI), the Iran Fisheries Organization, and the Union of Aquatic Production and Trade of Iran for their invaluable cooperation in conducting this research. Their support and collaboration were essential in the successful completion of this study. 15 25 2023/12/232024/12/24 1403/10/4 2025/02/282025/02/28 1403/12/10 حسین سعیدی Hosein Saeedi دانشگاه تهران Iran hosein.saeedi@ut.ac.ir یزدان مرادی Yazdan Moradi موسسه تحقیقات علوم شیلاتی کشور Iran ymorady@yahoo.com عباس مختاری آبکناری Abbas Mokhtari Abkenari سازمان شیلات ایران Iran mokhtari48@gmail.com Export China Shrimp Iran Market صادرات چین میگو ایران بازار Adli, A., Bayi, H. and Pendar., 2020. Identification and ranking of factors affecting the export of fisheries products in Iran. Iranian Journal of Fisheries Science, 29(1), pp. 13-25. (in Persian)##Ali Akbarzadeh Bidgoli, M., 2018. Examination of the production and export status of shrimp in Iran and determining the factors affecting shrimp exports, Rey, Payame Noor University. (in Persian)##Aquatics' Production and Trade :union: of Iran., 2023. Iran's aquatic export statistics]. Available at: https://seairan.com (Retrieved at: 19 Feb 2024)##De Abreu, M. C. S., de Mattos, P., Lima, P. E. S., Padula, A. D., 2011. Shrimp farming in coastal Brazil: Reasons for market failure and sustainability challenges. Ocean & Coastal Management, 54(9), 658-667.‌##FAO,. 2022. GLOBEFISH Highlights – International markets on fisheries and aquaculture products, second issue 2022, with January–December 2021 Statistics. DOI: 10.4060/cb9285en##Heidarian, K., 2011. Factors affecting shrimp exports in Iran, Tehran, Payame Noor University, Faculty of Management. (in Persian)##Kalafsky, R. V., 2009. Export challenges and potential strategies: Canadian manufacturers in the Chinese market. Journal of Small Business and Enterprise Development, 16(1), 47-59.##Khanh Nguyen, H. T., Nang Thu, T. T., Lebailly, P., Azadi, H., (2019). Economic challenges of the export-oriented aquaculture sector in Vietnam. Journal of Applied Aquaculture, 31(4), 367-383.‌##Islamic Republic of Iran Customs Administration. 2023. Annual Statistics, available at: www.irica.ir (in Persian)##Iranian Fisheries Organization. , 2024. Statistical Yearbook of Fisheries 2024. (in Persian)##Meltzer, L., Chang, J. O., 2006. Export market influence on the development of the Pacific shrimp fishery of Sonora, Mexico. Ocean & coastal management, 49(3-4), 222-235.‌##Morazavi, S.B., 2014. Determining factors and commercial potentials of Iranian shrimp exports in the European :union:; using the gravity model. Journal of Agricultural Economics Research. 6(3), 21-41.##Norouzi, M., 2019. Examination of factors affecting the development of aquatic exports, Rey, Payame Noor University, Faculty of Management. (in Persian)##TaleiPoor, M.R., Heidarieh, S.A., Khanzadi, H., Vakil Alroaia, Y., (2019). Export performance improvement model of Iranian farmed shrimp with grounded theory approach. Iranian Scientific Fisheries Journal Vol.29, No.2, 115-125.##Tehran Chamber of Commerce, Industries, Mines and Agriculture, 2023. Import and Export Statistics, available at: https://tccim.ir/stats (in Persian)## ##

مقاله علمی – پژوهشی:‌ همبستگی بین آلودگی میکروپلاستیک و عناصر با پتانسیل سمیت در رسوبات سواحل جنوب غربی دریای خزر Correlation between microplastic pollution and potentially toxic elements in the sediments of the Southwestern Caspian Sea Coastline 1 1 این مطالعه با هدف ارزیابی همبستگی آماری بین آلودگی میکروپلاستیک و عناصر با پتانسیل سمیت در رسوبات سواحل جنوب غربی دریای خزر در سه ایستگاه نمونه ‌برداری (کیاشهر، انزلی و آستارا) انجام شد. برای استخراج میکروپلاستیک‌‌ها از روش هضم مواد آلی با استفاده از پراکسید هیدروژن (H2O2، %30) و روش جداسازی چگالی با محلول اشباع نمک NaCl استفاده شد. غلظت عناصر با استفاده از دستگاه طیف ‌سنجی جرمی پلاسمای جفت ‌شده القایی (ICP-MS) اندازه‌‌گیری شد. نتایج نشان داد که بیشترین میانگین غلظت عناصر در رسوبات مربوط به منگنز با 41/53±80/760661 میکروگرم بر کیلوگرم وزن خشک در ایستگاه انزلی و کمترین غلظت مربوط به کادمیوم با 93/1±44/41 میکروگرم بر کیلوگرم وزن خشک در ایستگاه آستارا بود. آلودگی میکروپلاستیک در ایستگاه انزلی با 4±67 قطعه در 300 گرم رسوب خشک بیشترین فراوانی را نشان داد. میکروپلاستیک‌های استخراجی از رسوبات از نوع رشته‌ای بودند و در دو رنگ آبی و قرمز مشاهده شدند که در مجموع رنگ آبی با 58% بیشترین فراوانی را به‌خود اختصاص داد. بیشترین فراوانی میکروپلاستیک‌ها در اندازه‌های 5-4 میلی‌‌متر و بزرگتر از 5 میلی‌‌متر مشاهده شد. تجزیه‌وتحلیل FTIR-ATR 5 نوع پلیمر شامل پلی‌اتیلن، پلی‌پروپیلن، پلی‌استر، پلی‌استایرن و نایلون را شناسایی کرد. پلی‌اتیلن فراوان‌ترین میکروپلاستیک شناسایی‌شده بود. تحلیل همبستگی بین فراوانی میکروپلاستیک‌‌ها و غلظت عناصر نشان داد که هیچ‌ گونه ارتباط معنی‌‌داری بین این دو متغیر وجود ندارد. این نتایج حاکی از آن است که آلودگی میکروپلاستیک ‌و عناصر با پتانسیل سمیت به ‌طور مستقل اثرات متفاوتی بر اکوسیستم‌های دریایی سواحل جنوب غربی دریای خزر دارند. این یافته‌ها اهمیت پایش مستمر و توسعه روش‌های کارآمد برای مدیریت آلودگی‌های دریایی را در این منطقه، برجسته می‌کند.       2 Introduction Microplastics (MPs) have garnered significant attention due to their widespread presence in the environment and the potential threats they pose to aquatic organisms (Wang et al., 2021). These particles, smaller than 5 millimeters, are classified into primary and secondary types. Primary microplastics are manufactured in micrometer sizes for use in various industries, including aerospace, medicine, and cosmetics (Alomar et al., 2016). In contrast, secondary microplastics are formed from the breakdown of larger plastic debris into smaller particles (Duis and Coors, 2016). Microplastics readily accumulate in aquatic environments and, due to their resistance to degradation, are dispersed globally (Wang et al., 2021). These particles can adversely affect aquatic organisms due to their physical and chemical properties, leading to disturbances in feeding, reproduction, and immune functions (Oliviero et al., 2019). Additionally, microplastics can adsorb pollutants such as heavy metals, exacerbating their harmful effects on aquatic ecosystems. This combination presents a significant threat to marine life health (Prunier et al., 2019). Furthermore, microplastics provide a substrate for microorganisms, facilitating the formation of biofilms. These biofilms can alter the physical and chemical properties of microplastics, influencing their ability to adsorb contaminants (Tu et al., 2020). The objective of this study is to examine the correlation between microplastic pollution and potentially toxic elements in the sediments of the southwestern Caspian Sea coast and assess their impacts on the region marine ecosystem. Methodology The Caspian Sea, the largest enclosed lake in the world, is significantly impacted by human activities such as oil and gas extraction, agriculture, and industrial development. Rivers such as the Volga, Kura, and Ural transport pollutants, including heavy metals, to the sea, posing a threat to the ecosystem, particularly along the southwestern coast (Efendieva, 1994; Simonett, 2006). Sediment sampling was conducted at three polluted stations in Kiashahr, Anzali, and Astara (Kostianoy et al., 2005). Sediment sampling was performed in the spring of 2022 using Van Veen grabs (20×20 cm) with three replicates at each statio (Claessens et al., 2011; Löder and Gerdts, 2015). After being transferred to glass bottles and sent to the laboratory. Microplastic extraction from sediments involves two essential stages. In the first stage, the organic materials in the sediments were digested using hydrogen peroxide (H2O2, 30%). The digestion time varies between 1 and 10 days, depending on the type and amount of organic material (Erkes-Medrano et al., 2015; Zhang et al., 2016). After digestion, the samples were dried at 60°C for 48 hours (Vianello et al., 2013). In the second stage, density separation was used to extract the microplastics. In this step, 100 g of dried sediment was placed in a glass beaker, and 800 mL of saturated NaCl solution (293 g/L) was added (Thompson et al., 2004). After shaking for five minutes, the beaker was left to stand for 45 minutes to allow the high-density particles to settle. The resulting supernatant, containing the floating particles, was filtered through a nitrocellulose filter (Hidalgo-Ruz et al., 2012; Wagner et al., 2014; Duis and Coors, 2016). This process was repeated three times, and the filters were dried at 60°C (Law et al., 2010). Finally, the microplastic particles were examined and counted using a 40x magnification loop, and the number of microplastic particles per gram of dry sediment was reported (Reddy et al., 2006; Morét-Ferguson et al., 2010). The polymer types of the extracted microplastics were identified using FT-IR spectroscopy with ATR, analyzing spectra in the 400-4000 cm⁻¹ range and comparing characteristic peaks with standard polymer databases (Veerasingam et al., 2021). Data analysis was performed using SPSS version 27. The Kolmogorov-Smirnov test was used to check for normality, and to compare pollution levels across stations, ANOVA and Kruskal-Wallis tests were applied. To examine the correlation between microplastic pollution and potentially toxic elements, Pearson and Spearman correlation coefficients were used. All analyses were conducted at a %95 confidence level. Graphs were plotted using Excel 2022. Results The average concentration of elements at the three stations revealed that the highest and lowest average concentrations of elements in the sediment were for manganese (Mn) with 760661.80±53.41 µg/kg dry weight at the Anzali station and cadmium (Cd) with 41.44±1.93 µg/kg dry weight at the Astara station. The results of the Kolmogorov-Smirnov test for the distribution of potentially toxic elements in the sediment samples from the stations indicated that some elements did not follow a normal distribution (p˂0.05). To compare the average concentrations of elements across the stations and examine the correlation between elements, parametric tests (one-way analysis of variance and Pearson correlation coefficient) were used for normally distributed data, while non-parametric tests (Kruskal-Wallis and Spearman correlation coefficient) were employed for non-normally distributed data. One-way analysis of variance (ANOVA) results for comparing the average concentration of elements across the stations showed that manganese and zinc had significant differences at all stations (p˂0.05). The cadmium element showed no significant difference between the Kiashahr and Astara stations, but significant differences were observed between Kiashahr and Anzali, as well as Anzali and Astara stations (p˂0.05). The Kruskal-Wallis test results also indicated significant differences for arsenic, cobalt, chromium, copper, iron, mercury, nickel, and lead among the stations (p˂0.05). The Anzali station, with 67±4 pieces per 300 grams of dry sediment, exhibited the highest contamination, while the Kiashahr station, with 45.33±2.30 pieces per 300 grams of dry sediment, showed the lowest contamination. One-way analysis of variance (ANOVA) revealed that the Anzali station had a significant difference when compared to both Kiashahr and Astara stations (p˂0.05). However, no significant difference was observed between the Kiashahr and Astara stations. The microplastics extracted from the sediment samples were categorized into two color groups: blue and red. At the Kiashahr station, red microplastics accounted for 53%, representing the highest abundance, while blue microplastics constituted 47%, representing the lowest abundance. At the Anzali station, blue microplastics were the most abundant, comprising 75%, while red microplastics represented the lowest abundance, constituting 25%. At the Astara station, red microplastics accounted for 53%, representing the highest abundance, while blue microplastics constituted 47%, representing the lowest abundance. A total of 496 microplastic pieces were extracted from the sediment samples at the three stations. All the extracted microplastics were fiber type. The microplastics found in the sediment samples were classified into seven categories: less than 0.5 mm, 0.5-1 mm, 1-2 mm, 2-3 mm, 3-4 mm, 4-5 mm and greater than 5 mm. At the Kiashahr station, the highest abundance of microplastics was found in the 4-5 mm range, followed by the 3-4 mm range. The lowest abundance was observed in the 1-2 mm particles. At the Anzali station, the highest abundance was found in particles larger than 5 mm, followed by the 4-5 mm range, while the lowest abundance was observed in particles smaller than 0.5 mm. At the Astara station, the highest abundance was found in particles larger than 5 mm, followed by the 4-5 mm range, while the lowest abundance was observed in the 1-2 mm particles. The extracted microplastics from the sediments of the southwestern Caspian Sea coast were identified using FTIR-ATR spectroscopy. Five different polymers were identified, including polyethylen (PE), polypropylene (PP), polyester, polystyrene (PS) and nylon. Overall, polyethylene was the dominant polymer in the extracted microplastics from the sediments. The correlation analysis results between the abundance of microplastics and the concentration of potentially toxic elements in the sediments from the Kiashahr, Anzali, and Astara stations indicated no significant correlation between these two variables at the stations under study. Manganese, zinc, and cadmium had a normal distribution in all stations, thus Pearson's correlation coefficient was used to assess the correlation between microplastic pollution and potentially toxic elements. For other elements, whose data did not follow a normal distribution and successful normalization techniques were not applied, the Spearman correlation coefficient was employed. Discussion and conclusion In this study, the Anzali station exhibited the highest contamination, with an average of 67 ± 4 microplastic pieces per 300 grams of dry sediment. This finding is consistent with the study by Rasta et al. (2020) which reported a high concentration of microplastic contamination in the sediments of Anzali Wetland. All the microplastics extracted from the sediments in this research were of the fiber type, with blue being the most dominant color, accounting for 58%. Similar results were found in the study by Zhang et al., (2020) in the Shengsi region of China, where fiber-type microplastics were the most abundant, with blue identified as the predominant color. Microplastics at the Kiashahr station were most abundant in the 4-5 mm size range, while the Anzali and Astara stations exhibited the highest abundance in microplastics larger than 5 mm. Similar findings were reported by Kühn et al., (2018) on the coasts of the Netherlands, where microplastics in the size range of 500-2000 micrometers were predominant. In this study, no significant correlation was observed between microplastics and the concentration of elements in the sediments. This lack of correlation may be attributed to differences in the sources of microplastics and elements, the physical and chemical properties of these pollutants, and the varying environmental conditions (Napper and Thompson, 2016). Finally, it can be concluded that the Anzali station has the highest microplastic pollution, primarily composed of fiber type and secondary microplastics, with blue being the predominant color. Anthropogenic sources, such as laundry runoff, fishing gear, and the release of plastic packaging by tourists, contribute to the spread of this pollution in the marine environment. Correlation analysis revealed no significant relationship between microplastics and elements, likely due to differences in sources and the physical and chemical characteristics of these pollutants. A comparison of element concentrations with global standards indicates that the pollution levels are within safe limits; however, continued monitoring and management are crucial to mitigate pollution levels. 27 47 2023/12/232024/12/242025/02/2 1403/11/14 2025/02/282025/02/282025/02/28 1403/12/10 فرشته حاجی آقایی قاضی محله Fereshteh Haji Aghaei Ghazi Mahalleh گروه شیلات، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه سرا، ایران Iran fereshte.hj22@yahoo.com جاوید ایمانپور نمین Javid Imanpour Namin گروه شیلات، دانشکده منابع طبیعی، دانشگاه گیلان، صومعه سرا، ایران Iran javidiman@gmail.com Caspian Sea Microplastic Potentially toxic elements Sediments Statistical correlation دریای خزر میکروپلاستیک عناصر با پتانسیل سمیت رسوبات FTIR-ATR Abidli, S., Toumi, H., Lahbib, Y. and El Menif, N.T., 2017. The first evaluation of microplastics in sediments from the complex lagoon-channel of Bizerte (Northern Tunisia). Water, Air, and Soil Pollution, 228(7): 262. DOI:10.1007/s11270-017-3439-9.##Alimba, C.G., and Faggio, C., 2019. Microplastics in the marine environment: Current trends in environmental pollution and mechanisms of toxicological profile. Environmental Toxicology and Pharmacology, 68: 61-74. DOI:10.1016/j.etap.2019.03.001.##Alomar, C., Estarellas, F., Deudero, S., 2016. Microplastics in the Mediterranean Sea: Deposition in coastal shallow sediments, spatial variation and preferential grain size. Marine Environmental Research, 115: 1-10. DOI:10.1016/j.marenvres.2016.01.005.##Andrady, A.L., 2011. Microplastics in the marine environment. Marine Pollution Bulletin, 62(8): 1596–1605. DOI:10.1016/j.marpolbul.2011.05.030.##Arthur, C., Baker, J. and Bamford, H., 2008. Proceedings of the International Research Workshop on the Occurrence, Effects and Fate of Microplastic Marine Debris. NOAA Technical Memorandum. National Oceanic and Atmospheric Administration, 30:2008. DOI:10.1016/j.envlope.2008.136598.##Avio, C.G., Pittura, L., d'Errico, G., Abel, S., Amorello, S., Marino, G., Gorbi, S., and Regoli, F., 2020. Distribution and characterization of microplastic particles and textile microfibers in Adriatic food webs: General insights for biomonitoring strategies. Environmental Pollution, 258: 113766. DOI:10.1016/j.envpol.2019.113766.##Bagheri, H., and Darvish Bastami. K., 2022. Investigation of Heavy Metal Concentrations in Estuarine Sediments of Important Rivers in The Southern Part of the Caspian Sea. Environment and Water Engineering, 8(1): 31-46. DOI:10.22034/JEWE.2021.286828.1569.##Barnes, D.K., Galgani, F., Thompson, R.C., and Barlaz, M., 2009. Accumulation and fragmentation of plastic debris in global environments. Philosophical Transactions, 364(1526): 1985-1998. DOI:10.1098/rstb.2008.0205.##Bastami, K., Bagheri, H., Haghparast, S., Soltani, F. and Hamzehpoor, A., 2014. Distribution and ecological risk assessment of heavy metals in surface sediments along southeast coast of the Caspian Sea. Marine Pollution Bulletin, 81: 262–267. DOI:10.1016/j.marpolbul.2014.01.029.##Benson, N.U., and Fred-Ahmadu, O.H., 2020. Occurrence and distribution of microplastics-sorbed phthalic acid esters (PAEs) in coastal psammitic sediments of tropical Atlantic Ocean. Gulf of Guinea. Science of The Total Environment, 730: 139013. DOI:10.1016/j.scitotenv.2020.139013.##Boucher, J. and Friot, D., 2017. Primary microplastics in the oceans: a global evaluation of sources. Marine Pollution, 2002: 46. DOI:10.2305/IUCN.CH.2017.01.en.##Browne, M.A., Galloway, T.S. and Thompson, R.C., 2010. Spatial patterns of plastic debris along estuarine shorelines. Environmental Science and Technology. 44(9): 3404-3409. DOI:10.1021/es903784e.##Castro, R.O., Silva, M.L., and da Araújo, F.V., 2018. Review on microplastic stud-ies in Brazilian aquatic ecosystems. Ocean and Coastal Management, 165: 385-400. DOI: 10.1016/j.ocecoaman.2018.09.013.##CCME, 2001. Canadian Council of Ministers of the Environment. Canadian Sediment Quality Guidelines for the Protection of Aquatic Life: Interim Sediment Quality Guidelines. Canadian Environmental Quality Guidelines.##Cesa, F.S., Turra, A., and Baruque-Ramos, J., 2017. Synthetic fibers as microplastics in the marine environment: a review from textile perspective with a focus on domestic washings. Science of The Total Environment 598: 1116-1129. DOI:10.1016/j.scitotenv.2017.04.172.##Claessens, M., De Meester, S., Van Landuyt, L., De Clerck K., and Janssen, C.R., 2011. Occurrence and distribution of microplastics in marine sediments along the Belgian coast. Marine Pollution Bulletin, 62(10): 2199-2204. DOI:10.1016/j.marpolbul.2011.06.030. ##Dou, Y., Li, J., Zhao, J., Hu, B., and Yang, S., 2013. Distribution, Enrichment and Source of Heavy Metals in Surface Sediments of the Eastern Beibu Bay, South China Sea. Marine Pollution Bulletin, 67 (1-2): 137–145. DOI:10.1016/j.marpolbul.2012.11.022.##Duis, K., and Coors, A., 2016. Microplastics in the aquatic and terrestrial environment: sources (with a specific focus on personal care products), fate and effects. Environmental Sciences Europe, 28(1): 2. DOI:10.1186/s12302-015-0069-y.##Éfendieva, I.M., 1994. Ecological problems of oil exploitation in the Caspian Sea area. Journal of Petroleum Science and Engineering, 28(4): 227-231. DOI:10.1016/S0920-4105(00)00081-4.##Eriksen, M., Mason, S., Wilson, S., Box, C., Zellers, A., Edwards, W., Farley, H. and Amato, S., 2013b. Microplastic pollution in the surface waters of the Laurentian Great Lakes. Marine Pollution Bulletin, 77(1-2): 177-182. DOI: 10.1016/j.marpolbul.2013.10.007.##Franciskovic-Bilinski, S., 2008. Detection of geochemical anomalies in stream sediments of the upper Sava River drainage basin (Slovenia, Croatia). Fresenius Environmental Bulletin, 17(2): 188-196. DOI:10.1016/publication/259194804.##Galindo Montero, A.A., Costa-Redondo, L.C., Vasco-Echeverri, O., and Arana, V.A., 2023. Microplastic pollution in coastal areas of Colombia: review. Marine Environmental Research, 190: 106027. DOI:10.1016/j.marenvres.2023.106027.##Ghazban, F., and Zarei, M., 2011. Investigation of the Source of Heavy Metal Pollution in the Sediments of Anzali Lagoon (Northern Iran). Environmental Journal, 37(57): 45-65. DOI:20.1001.1.10258620.1390.37.57.6.4. (In Persian).##Graca, B., Szewc, K., Zakrzewska, D., Dołęga, A., and Szczerbowska-Boruchowska, M., 2017. Sources and fate of microplastics in marine and beach sediments of the Southern Baltic Sea a preliminary study. Environmental Science and Pollution Research, 24(8): 7650-7661. DOI:10.1007/s11356-017-8419-5.##He, Z.L., Yang, X.E., and Stoffella, P.J., 2005. Trace elements in agroecosystems and impacts on the environment. Journal of Trace Elements in Medicine and Biology, 19(2-3): 125-140. DOI:10.1016/j. jtemb.2005.02.010.##Hidalgo-Ruz, V., Gutow, L., Thompson, R.C., and Thiel, M., 2012. Microplastics in the marine environment: a review of the methods used for identification and quantification. Environmental Science and Technology, 46(6): 3060-3075. DOI:10.1021/es2031505.##Huang, C., Ge, Y., Yue, S., Zhao, L., and Qiao, Y., 2021. Microplastics aggravate the joint toxicity to earthworm Eisenia fetida with cadmium by altering its availability. Science of The Total Environment, 753: 142042. DOI:10.1016/j.scitotenv.2020.142042.##IARC, 2019. Agents classified by the IARC monographs, 112(1): 30-37. DOI:10.1093/jnci/djz169.##Jang, Y.C., Lee, J., Hong, S., Lee, J.S., Shim, W.J., and Song, Y.K., 2014. Sources of plastic marine debris on beaches of Korea: more from the ocean than the land. Ocean Science Journal, 49: 151-162. DOI:10.1007/s12601-014-0015-8.##Jiang, C., Yin, L., Wen, X., Du, C., Wu, L., Long, Y., Liu, Y., Ma, Y., Yin, Q., Zhou, Z., and Pan, H., 2018. Microplastics in sediment and surface water of west dongting lake and south dongting lake: abundance, source and composition. International Journal of Environmental Research and Public Health, 15(10): 2164. DOI:10.3390/ijerph15102164.##Kazour, M., Jemaa, S., Issa, C., Khalaf, G., and Amara, R., 2019. Microplastics pollution along the Lebanese coast (Eastern Mediterranean Basin): Occurrence in surface water, sediments and biota samples. Science of The Total Environment, 696: 133933. DOI:10.1016/j.scitotenv.2019.133933.##Kim, K.T., Ra, K., Kim, E.S., Yim, U.H., and Kim, J.K., 2011. Distribution of heavy metals in the surface sediments of the Han River and its estuary, Korea. Journal of Coastal Research, 64: 903-907. DOI:10.1016/jstore/stable/26482304.##Kostianoy Andrey, G., Aleksey, N. and Kosarev. A., 2005. The Handbook of Environmental Chemistry. Water Pollution, 205: 37. DOI:10.1016/02/3141YL-543210.##Kowalski, N., Reichardt, A.M. and Waniek, J.J., 2016. Sinking rates of microplastics and potential implications of their alteration by physical, biological, and chemical factors. Marine Pollution Bulletin, 109: 310-319. DOI:10.1016/j.marpolbul.2016.05.064.##Kühn, S., Van Oyen, A., Booth, A.M., Meijboom, A., and Van Franeker, J.A., 2018. Marine microplastic: Preparation of relevant test materials for laboratory assessment of ecosystem impacts. Chemosphere, 213: 103-113. DOI:10.1016/j.chemosphere.2018.09.032. ##Kumar, V., Parihar, R.D., Sharma, A., Bakshi, P., Singh Sidhu, G.P., Bali, A.S., Karaouzas, I., Bhardwaj, R., Thukral, A.K., Gyasi-Agyei, Y., and Rodrigo-Comino, J., 2019. Global evaluation of heavy metal content in surface water bodies: a meta-analysis using heavy metal pollution indices and multivariate statistical analyses. Chemosphere. DOI:10.1016/j.chemosphere.2019.124364.##Law, K.L., Morét-Ferguson, S., Maximenko, N.A., Proskurowski, G., Peacock, E.E., Hafner, J., and Reddy, C.M., 2010. Plastic accumulation in the North Atlantic subtropical gyre. Science, 329(5996): 1185-1188. DOI:10.1126/science .1192321.##Liu, S., Shi, J., Wang, J., Dai, Y., Li, H., Li, J., Liu, X., Chen, X., Wang, Z., and Zhang, P., 2021a. Interactions between microplastics and heavy metals in aquatic environments: a review. Frontiers in Microbiology, 12: 652520. DOI:10.3389/fmicb.2021.652520.##Löder, M.G., and Gerdts, G., 2015. Methodology used for the detection and identification of microplastics a critical appraisal. Marine Anthropogenic Litter, 201-227. DOI:10.1007/978-3-319-16510-3_8.##Long, E.R., MacDonald, D.D., Smith, S.L., and Calder, F.D., 1995. Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuarine sediments. Journal of Environmental Management, 19(1): 81–97. DOI:10.1007/BF02472006.##Mataji, A., Taleshi, M.S., and Balimoghaddas, E., 2020. Distribution and Characterization of Microplastics in Surface Waters and the Southern Caspian Sea Coasts Sediments. Archives of Environmental Contamination and Toxicology, 78(1): 86-93. DOI:10.1007/s00244-019-00700-2. ##Mehdinia, A., Dehbandi, R., Hamzehpour, A., and Rahnama, R., 2020. Identification of microplastics in the sediments of southern coasts of the Caspian Sea, north of Iran. Environmental Pollution, 258: 113738. DOI:10.1016/j.envpol.2019.113738. ##Mishra, S., Rath, C., and charan Das, A.P., 2019. Marine microfiber pollution: a review on present status and future challenges. Marine Pollution Bulletin, 140: 188–197. DOI:10.1016/j.marpolbul.2019.01.039.##Mohammadi Galangash, M., Solgi, E., and Bozorgpanah, Z., 2017. An assessment of heavy metals in coastal sediments of the Caspian Sea, Guilan Province. Journal of Oceanography, 8(31): 27-34. DOI:10.29252/joc.8.31.27. (In Persian).##Mohsen, M., Wang, Q., Zhang, L., Sun, L., Lin, C., and Yang, H., 2019. Microplastic ingestion by the farmed sea cucumber Aposticopus japonicus in China. Environmental Pollution, 245: 1071–1078. DOI:10.1016/j.envpol.2018.11.083.##Morét-Ferguson, S., Law, K.L., Proskurowski, G., Murphy, E.K., Peacock, E.E., and Reddy, C.M., 2010. The size, mass and composition of plastic debris in the western North Atlantic Ocean. Marine Pollution Bulletin, 60(10):1873-1878. DOI:10.1016/j.marpolbul.2010.07.020.##Naji, A., Esmaili, Z., Mason, S.A., and Vethaak, A.D., 2017. The occurrence of microplastic contamination in littoral sediments of the Persian Gulf, Iran. Environmental Science and Pollution Research, 24(25): 20459-20468. DOI:10.1007/s11356-017-9587-z. ##Napper, I.E., and Thompson, R.C., 2016. Release of synthetic microplastic plastic fibres from domestic washing machines: Effects of fabric type and washing conditions. Marine Pollution Bulletin, 112(1-2): 39-45. DOI:10.1016/j.marpolbul.2016.09.025. ##Nasrabadi, T., Nabi, R., Karbassi, A.R., and Mehrdadi, N., 2010. Evaluating the efficiency of sediment metal pollution indices in interpreting the pollution of Haraz River sediments, southern Caspian Sea basin. Environmental Monitoring and Assessment, 171(1-4): 395-410. DOI:10.1007/s10661-009-1286-x.##Okogbue, C.O., Oyesanya, O.U., Anyiam, O.A., and Omonona, V.O., 2017. Assessment of pollution from produced water discharges in seawater and sediments in offshore, Niger Delta. Environmental Earth Sciences, 76. DOI:10.1007/s12665-017-6682-x.##Oliviero, M., Tato, T., Schiavo, S., Fernandez, V., Manzo, S., and Beiras, R., 2019. Leachates of micronized plastic toys provoke embryotoxic effects upon sea urchin Paracentrotus lividus. Environmental Pollution, 247: 706–715. DOI:10.1016/j. envpol.2019.01.098.##Pittura, L., Avio, C.G., Giuliani, M.E., d’Erricol, G., Keiter, S.H., Cormier, B., Gorbi, S., and Regoli, F., 2018. Microplastics as vehicles of environmental PAHs to marine organisms: combined chemical and physical hazards to the mediterranean mussels, Mytilus galloprovincialis. Frontiers in Marine Science, 5: 103–132. DOI:10.3389/fmars.2018.00103.##Prunier, J., Maurice, L., Perez, E., Gigault, J., Pierson-Wickmann, A., and Davranche, M., 2019. Trace metals in polyethylene debris from the North Atlantic subtropical gyre. Environmental Pollution, 245: 371–379. DOI:10.1016/j.envpol.2018. 10.043.##Ramazanova, E., Bahetnur, Y., Yessenbayeva, K., Lee, S.H., and Lee, W., 2022. Spatiotemporal evaluation of water quality and risk assessment of heavy metals in the northern Caspian Sea bounded by Kazakhstan. Marine Pollution Bulletin, 181: 113879. DOI:10.1016/j.marpolbul.2022.113879.##Rasta, M., Sattari, M., Taleshi, M.S., and Imanpour Namin, J., 2020a. Identification and distribution of microplastics in the sediments and surface waters of Anzali Wetland in the Southwest Caspian Sea, Northern Iran. Marine Pollution Bulletin, In press.##Rasta, M., Sattari, M., Taleshi, M.S., and Imanpour Namin, J., 2020b. Identification and distribution of microplastics in the sediments and surface waters of Anzali Wetland in the Southwest Caspian Sea, Northern Iran. Marine Pollution Bulletin, 160: 111541. DOI:10.1016/j.marpolbul.2020.111541.##Reddy, M.S., Basha, S., Adimurthy, S., and Ramachandraiah, G., 2006. Description of the small plastics fragments in marine sediments along the Alang-Sosiya ship-breaking yard, India. Estuarine. Coastal and Shelf Science, 68: 656−660. DOI:10.1016/j.ecss.2006.03.018.##Reisser, J.W., Slat, B., Noble, K., du Plessis, K., Epp, M., Proietti, M.C., de Sonneville, J.D., Becker, T., and Pattiaratchi, C., 2015. The vertical distribution of buoyant plastics at sea: An observational study in the North Atlantic Gyre. Biogeosciences, 12(4): 1249-1256. DOI:10.5194/bg-12-1249-2015.##Rocha-Santos, T., and Duarte, A., 2017. Characterization and Analysis of Microplastics. In: Comprehensive Analytical Chemistry, 75. Elsevier.##Rodríguez-Grim´on, R., Campos, N.H., and Castro, I.B., 2021. Effect of maritime traffic on water quality parameters in Santa Marta, Colombia. Journal of Marine Science and Engineering, 9: 474. DOI:10.3390/jmse9050474.##Saeedi, M., Abessi, O., and Jamshidi, A., 2009. Assessment of heavy metal and oil pollution in surface sediments of South Eastern Caspian Sea using indices. Journal of Environmental Studies, 36(53): 21-38. DOI:10.1016/publication/286381609. (In Persian).##Santana, C.S., Montalvan, D.M., Olivares, A., Silva, V.H.C., Luzardo, F.H.M., Velasco, F.G., and De Jesus, R.M., 2020. Assessment of water resources pollution associated with mining activity in a semi-arid region. Journal of Environmental Management, 273: 111148. DOI:10.1016/j.jenvman.2020.111148.##Shim, W.J., Hong, S.H., and Eo, S., 2018. Marine microplastics: abundance, distribution, and composition. Microplastic Contamination in Aquatic Environments, 1-26. DOI:10.1016/B978-0-12-813747-5.00001-1.##Simonett, O., 2006. Vital Caspian Graphics; Challenges beyond caviar, United Nations Environment program and Caspian Environment program, Publishing by Andishe Pouya.##So, W.K., Chan, K., and Not, C., 2018. Abundance of plastic microbeads in Hong Kong coastal water. Marine Pollution Bulletin, 133: 500-505. DOI:10.1016/j. marpolbul.2018.05.066.##Stolte, A., Forster, S., Gerdts, G., and Schubert, H., 2015. Microplastic concentrations in beach sediments along the German Baltic coast. Marine Pollution Bulletin, 99(1-2): 216-229. DOI:10.1016/j.marpolbul.2015.07.022.##Thompson, R.C., Olsen, Y., Mitchell, R.P., Davis, A., Rowland, S.J., John, A.W.G., McGonigle, D., and Russell, A.E., 2004. Lost at sea: where is all the plastic. Science, 304: 838. DOI:10.1126/science.1094559.##Tibbetts, J., Krause, S., Lynch, I., and Sambrook Smith, G.H., 2018. Abundance, distribution, and drivers of microplastic contamination in urban river environments. Water, 10(11): 1597. DOI:10.3390/w10111597. ##Townsend, K.R., Lu, H.C., Sharley, D.J., and Pettigrove, V., 2019. Associations between microplastic pollution and land use in urban wetland sediments. Environmental Science and Pollution Research, 26(22): 22551-22561. DOI:10.1007/s11356-019-04885-w.##Tsang, Y.Y., Mak, C.W., Liebich, C., Lam, S.W., Sze, E.T., and Chan, K.M., 2017. Microplastic pollution in the marine waters and sediments of Hong Kong. Marine Pollution Bulletin, 115(1-2): 20-28. DOI:10.1016/j.marpolbul.2016.11.003.##Tu, C., Chen, T., Zhou, Q., Liu, Y., Wei, J., and Waniek, J., 2020. Biofilm formation and its influences on the properties of microplastics as affected by exposure time and depth in the seawater. Science of The Total Environment, 734: 139237. DOI:10.1016/j.scitotenv.2020.139237.##Turner, A., and Holmes, L.A., 2015. Adsorption of trace metals by microplastic pellets in fresh water. Environmental Chemistry, 12(5): 600–610. DOI:10.1071/En14143.##Vedolin, M.C., Teophilo, C.Y.S., Turra, A., and Figueira, R.C.L., 2018. Spatial variability in the concentrations of metals in beached microplastics. Marine Pollution Bulletin, 129: 487–493. DOI:10.1016/j.marpolbul.2017.10.019.##Vianello, A., Boldrin, A., Guerriero, P., Moschino, V., Rella, R., Sturaro, A., and Da Ros, L., 2013. Microplastic particles in sediments of Lagoon of Venice, Italy: First observations on occurrence, spatial patterns and identification. Estuarine Coastal and Shelf Science, 130: 54-61. DOI:10.1016/j.ecss.2013.03.022.##Wagner, M., Scherer, C., Alvarez-Mu~noz, D., Brennholt, N., Bourrain, X., Buchinger, S., Fries, E., Grosbois, C., Klasmeier, J., Marti, T., Rodriguez-Mozaz, S., Urbatzka, R., Vethaak, A., Winther-Nielsen, M., and Eifferscheid, G., 2014. Microplastics in freshwater ecosystems: what we know and what we need to know. Environmental Sciences Europe, 26(1): 1-9. DOI:10.1186/s12302-014-0012-7.##Wang, J., Li, J., Liu, S., Li, H., Chen, X., and Peng, C., 2021. Distinct microplastic distributions in soils of different land-use types: a case study of Chinese farmlands. Environmental Pollution, 269: 116199. DOI:10.1016/j.envpol.2020.116199.##Wen, B., Jin, S., Chen, Z., Gao, J., Liu, Y., and Liu, J., 2018a. Single and combined effects of microplastics and cadmium on the cadmium accumulation, antioxidant defence and innate immunity of the discus fish (Symphysodon aequifasciatus). Environmental Pollution, 243: 462–471. DOI:10.1016/j.envpol.2018.09. 029.##Yang, Y., Liu, W., Zhang, Z., Grossart, H., and Gadd, G.M., 2020. Microplastics provide new microbial niches in aquatic environments. Journal of Microbiology and Biotechnology, 104: 6501–6511. DOI:10.1007/s00253-020-10704-x.##Yu, X., Yan, Y., and Wang, W.X., 2013. The Distribution and Speciation of Trace Metals in Surface Sediments from the Pearl River Estuary and the Daya Bay, Southern China. Marine Pollution Bulletin, 60 (8): 1364–1371. DOI:10.1016/ j.marpolbul.2010.05.012.##Yuan, W., Liu, X., Wang, W., Di, M., and Wang, J., 2019. Microplastic abundance, distribution and composition in water, sediments, and wild fish from Poyang Lake, China. Ecotoxicology and Environmental Safety, 170: 180-187. DOI: 10.1016/j.ecoenv.2018.11.126.##Zeinolabedin, Y., Yahyapour, M.S., and Shirzad, Z., 2009. Geopolitics and Environmental Issues in the Caspian Sea, Caspian Journal of Environmental Sciences, 7 (2): 113-121. DOI:10.1016.556508/en.##Zhang, B., Chen, L., Chao, J., Yang, X., and Wang, J., 2020. Research progress of microplastics in freshwater sediments in China. Environmental Science and Pollution Research 27: 31046–31060. DOI:10.1007/s11356-020-09473-x.##Zhang, J., Zhou, F., Chen, C., Sun, X., Shi, Y., Zhao, H., and Chen, F., 2018. Spatial distribution and correlation characteristics of heavy metals in the seawater, suspended particulate matter and sediments in Zhanjiang Bay, China. PLOS ONE, 13: 0201414. DOI:10.1371/journal.pone.0201414.##Zhao, S., Zhu, L., and Li, D., 2015. Microplastic in three urban estuaries, China. Environmental Pollution, 206: 597-604. DOI:10.1016/j.envpol.2015.08.027. ##Zhu, L., Xu, J., Wang, F., and Lee, B., 2011. An Assessment of Selected Heavy Metal Contamination in the Surface Sediments from the South China Sea before 1998. Journal of Geochemical Exploration, 108 (1): 1-14. DOI:10.1016/j.gexplo.2010.08.002.## ##

مقاله علمی – پژوهشی:‌ اثر خوراکی سطوح مختلف کیتوزان بر عملکرد رشد، ترکیب لاشه و شاخص‌‌های ایمنی- بیوشیمیایی سرم خون فیل ‌ماهی (Huso huso) انگشت‌قد Dietary effect of different levels of chitosan on growth performance, carcass composition, and blood immune-biochemical indices of Beluga (Huso huso) fingerlings 1 1 تحقیق حاضر به منظور بررسی اثرات سطوح مختلف کیتوزان به عنوان یک مکمل غذایی محرک رشد و ایمنی بر عملکرد رشد، ترکیب لاشه و برخی شاخص‌‌های ‌‌خونی و سرم‌‌ شناسی بچه فیل‏ماهی پرورشی (Huso huso) طراحی و اجرا گردید. تعداد 1260 عدد ‏بچه فیل ‏ماهی (07/0±87/2 گرم) در 18 مخزن فایبر گلاس 2000 لیتری (70 عدد ماهی در هر مخزن) با شش جیره آزمایشی شامل جیره شاهد (فاقد کیتوزان، T1)، کیتوزان با مقادیر 15/0 درصد (T2)، 3/0 درصد (T3)، 45/0 درصد (T4)، 6/0 درصد (T5) و 75/0 درصد (T6) با 3 تکرار در هر تیمار به ‌‌مدت 12 هفته تغذیه شدند. وزن نهایی، شاخص رشد ویژه، نسبت بازده پروتئین و ضریب تبدیل غذایی ماهیان تغذیه شده با سطوح 45/0 درصد و بالاتر کیتوزان به طور معنی‌داری نسبت به نمونه شاهد کمتر بود (05/0p<). میزان پروتئین و چربی لاشه با افزایش میزان کیتوزان در جیره غذایی نسبت به گروه شاهد به‌ترتیب افزایش و کاهش معنی‌داری داشت (P≤0.05). شاخص‏های ایمنی لیزوزیم، کمپلمان ACH50، ایمونوگلوبولین تام و IgM نیز با افزایش میزان کیتوزان در جیره غذایی نسبت به گروه شاهد افزایش معنی‌‌داری یافت (05/0p<). در نتیجه، به منظور دستیابی به حداکثر رشد، ترکیب بهینه لاشه و شاخص‌‌های ایمنی- بیوشیمیایی خون در بچه فیل ماهی پرورشی، پیشنهاد می‏شود از میزان 6/0-45/0 درصد کیتوزان در جیره غذایی این ماهی استفاده گردد. 2 Introduction Aquaculture is increasingly vital for meeting the protein needs of a growing global population. Successful production relies on efficient feed, which accounts for 60% of costs, and the development of high-quality products. Disease management in aquaculture is challenging due to factors like poor nutrition and environmental conditions, making prevention more critical than treatment (Ndashe et al., 2023). Current strategies focus on using immune stimulants and additives, such as organic acids, probiotics, and prebiotics, to enhance fish health and resilience against diseases (Dawood et al., 2018). The use of natural growth stimulants like chitin, chitosan, and lactoferrin has surged due to their economic benefits and minimal environmental impact. These substances not only improve immune responses but also enhance the antibacterial activity of phagocytic cells, contributing to sustainable aquaculture practices. Overall, the shift towards these natural alternatives reflects a growing recognition of their value in promoting fish health and reducing reliance on chemical treatments. Chitosan is a biodegradable and biocompatible polysaccharide derived from glucosamine through the deacetylation of chitin, predominantly found in the exoskeletons of crustaceans, particularly shrimp shells. It offers numerous benefits in aquaculture, notably enhancing fish health and growth. Chitosan stimulates the immune system by increasing levels of immunoglobulin M (IgM) and lysozyme activity, which improves disease resistance. It also boosts antioxidant capacity by enhancing the activity of enzymes like superoxide dismutase (SOD) and catalase (CAT), thereby reducing oxidative stress. Additionally, chitosan promotes gut health by increasing intestinal villi length and digestive enzyme activity, facilitating better nutrient absorption (Mukarram et al., 2023; Zhang et al., 2024). Moreover, chitosan can chelate heavy metals such as cadmium, mitigating their toxic effects on fish, and its antibacterial properties help maintain gut microbiota balance by preventing pathogenic bacteria while promoting beneficial ones. Overall, dietary chitosan supplementation has been shown to enhance growth, health, and stress resistance in various fish species, making it a valuable additive in aquaculture. In the context of sturgeon (Huso huso) farming in Iran, reducing juvenile fish mortality and increasing growth rates are critical for economic efficiency, highlighting the importance of suitable diets and micronutrient balance to enhance immune function and production efficiency. Methodology The extraction of chitosan from shrimp shells was carried out through four stages: demineralization, deproteinization, decolorization, and deacetylation. 1260 fish (2.87 ± 0.07 g) after passing the acclimatization period, were fed in 18 tanks with six experimental diets, including control diet (without chitosan, T1), 0.15% (T2), 0.3% (T3), 0.45% (T4), 0.6% (T5) and 0.75% (T6) of chitosan (n=3) for 12 weeks. Then all growth indices such as final weight, growth rate, Protein Efficiency Ratio, and FCR, immunological parameters like lysozyme, ACH50, total immunoglobulin, and IgM were measured. The body composition also was measured after 12 weeks. Results The final body weight and body weight gain in treatments containing 0.45%, 0.6%, and 0.75% chitosan were significantly higher compared to the control, 0.15% and 0.3% chitosan treatments. The specific growth rate significantly increased with the higher levels of chitosan, and no significant difference was observed in the group fed with 0.15% chitosan compared to the control group. The hepatosomatic index significantly improved in all chitosan-fed treatments compared to the control group (P≤0.05). The feed conversion ratio significantly improved with increasing levels of chitosan compared to the control group. The protein efficiency ratio also increased in the treatments fed with 0.45%, 0.6%, and 0.75% chitosan compared to the control group, but no significant differences were found in the treatments fed with concentrations of 0.15% and 0.3% chitosan (P≥0.05). The lowest carcass protein level was observed in the control treatment, which showed a statistically significant difference compared to the carcass protein levels of other treatments, except for the 0.15% chitosan treatment (P ≤ 0.05). The carcass protein levels in the 0.45%, 0.6%, and 0.75% chitosan treatments were the highest, but no significant differences were observed among them. The carcass fat level in the 0.45%, 0.6%, and 0.75% chitosan treatments was significantly lower compared to the control group (P≤0.05). With the increase in chitosan concentration in the diets, the serum lysozyme levels significantly increased except for the group consuming 0.15% chitosan (P≤0.05). The results obtained from the complement activity (ACH50) measurements showed that with the increase in chitosan levels in the diet, this indicator significantly increased in the serum (P≤0.05). The total serum immunoglobulin and IgM levels, also increased significantly compared to the control group (P≤0.05). Discussion and conclusion Chitosan, has gained attention in aquaculture for its potential as a growth promoter and immunostimulant. Research indicates that dietary chitosan enhances growth performance, feed efficiency, and immune responses in various fish species, including Nile tilapia, common carp, and golden pompano. Optimal chitosan levels, typically ranging from 0.5% to 2%, have been shown to improve weight gain, feed conversion ratios, and overall health status by promoting gut health and enhancing digestive enzyme activities. Studies also highlight chitosan's role in modulating serum biochemical parameters, reducing fat accumulation in the liver, and improving intestinal morphology. The balance of chitosan dosage is crucial, as it can enhance beneficial bacteria while inhibiting harmful ones, thereby supporting the fish's immune system. Overall, chitosan represents a promising, eco-friendly alternative to antibiotics in aquaculture, contributing to sustainable fish farming practices while improving the health and productivity of cultured species. Chitosan also enhances nonspecific immunity and reduces mortality in fish, as evidenced by studies on common carp (Maqsood et al., 2010). However, its effects on feed consumption and conversion ratios can vary, with some studies showing no significant impact on these parameters despite improvements in liver health (Stanek et al., 2023). Overall, chitosan's role in aquaculture highlights its potential as a dietary supplement to improve fish health, growth, and resistance to environmental stressors. Serum parameter measurements are crucial for assessing the metabolic and physiological health of fish, particularly in aquaculture where they are susceptible to opportunistic bacterial infections. Lysozyme activity, an indicator of immune health, was found to increase with dietary chitosan levels. Research indicates that chitosan enhances lysozyme activity across various fish species, including loach, cobia, silver carp, vannamei shrimp, and rainbow trout. Additionally, chitosan supplementation in diets for beluga sturgeon and hybrid sturgeon also boosted lysozyme levels. Chitosan's immune-boosting effects are attributed to its ability to scavenge free radicals, enhancing innate immunity. Complement activity, vital for non-specific immune responses, also increased in fish like Nile tilapia and mrigal when fed chitosan. However, responses to chitosan vary by species and concentration, with some studies indicating potential negative effects at higher doses. Furthermore, IgM levels, a key immunoglobulin in fish, significantly increased with chitosan supplementation, reinforcing its role in adaptive immunity. Overall, optimal chitosan levels in fish diets can significantly enhance immune responses and health. The increase in IgM levels with dietary chitosan is not fully understood, necessitating further research to clarify the mechanisms involved (Salam et al., 2024). Studies indicate that chitosan enhances IgM and total protein levels in fish, such as rainbow trout and golden pompano, although excessive chitosan (10 g/kg) can reduce these benefits (Yu et al., 2023). In tilapia, IgM levels increased significantly up to 1.5% chitosan but decreased at 2% (Zhang et al., 2024). Additionally, recombinant chitosan nanoparticles show promise as alternatives to antibiotics in aquaculture, potentially enhancing disease resistance. This research supports using chitosan in beluga fry diets to improve growth and immune performance while reducing antibiotic reliance, particularly at levels of 0.45% to 0.6%, which positively affected growth, body composition, and immune parameters. Conflict of Interest The authors declare that they have no conflict of interest. Acknowledgment The authors wish to convey their heartfelt appreciation to all colleagues who supported and facilitated the experiment's necessary infrastructure. 49 65 2023/12/232024/12/242025/02/22024/10/12 1403/7/21 2025/02/282025/02/282025/02/282025/02/28 1403/12/10 محمود محسنی Mahmoud Mohseni انستیتو تحقیقات بین المللی ماهیان خاویاری Iran mahmoudmohseni73@gmail.com فاطمه فداکارماسوله Fatemeh Fadakar Masouleh انستیتو تحقیقات بین المللی ماهیان خاویاری Iran Fadakarfatemeh62@gmail.com مصطفی کرمی نسب Mostafa Karami Nasab 2- شرکت تولید خوراک آبزیان بهدانه شمال Iran Karaminasab@aol.com دنیا ذاکری Donya Zakeri دانشگاه شهید بهشتی Iran donyazakeri1@gmail.com Chitosan growth rate carcass composition blood parameter beluga فیل‌ماهی کیتوزان رشد ترکیب لاشه شاخص‌‌های ‌خونی AOAC. 1995.Official methods of analysis. 16th Edition. Arlington: Association of Official Analytical Chemists; ##Abdel-Tawwab, M., Abdel-Rahman, A.M., Ismael, N.E., 2008. Evaluation of commercial live bakers’ yeast, Saccharomyces cerevisiae as a growth and immunity promoter for Fry Nile tilapia, Oreochromis niloticus (L.) challenged in situ with Aeromonas hydrophila. Aquaculture, 280 (1-4):185-189. DOI: org/10.1016/j.aquaculture.2008.03.055## Abd El-Naby, A.S., Al-Sagheer, A.A., Negm, S.S., Naiel, M.A.E., 2020. Dietary combination of chitosan nanoparticle and thymol affects feed utilization, digestive enzymes, antioxidant status, and intestinal morphology of Oreochromis niloticus. Aquaculture 515, 734577. DOI:org/10.1016/j.aquaculture.2019.734577.##Abdel-Ghany, H.M., Salem, M.E.S., 2020. Effects of dietary chitosan supplementation on farmed fish; a review. Revaquacult 12(1):438–452. DOI: org/10. 1111/raq. 12326.##Abu-Elala, N.M., Mohamed, S.H., Zaki, M.M. and Eissa, A.E., 2015. Assessment of the immune-modulatory and antimicrobial effects of dietary chitosan on Nile tilapia (Oreochrmis niloticus) with special emphasis to its bio-remediating impacts. Fish & shellfish immunology, 46(2), pp.678-685. doi.org/10.1016/j.fsi.2015.08.004## Bag M.R., Makesh, M., Rajendran K.V., Mukherjee S.C., 2009. Characterization of IgM of Indian major carps and their cross-reactivity with anti-fish IgM antibodies. Fish Shellfish Immunol., 26: 275–278. doi.org/10.1016/j.fsi.2008.11.009.##Bhoopathy, S., Inbakandan, D., Rajendran, T., Chandrasekaran, K., Kasilingam, K., Gopal, D., 2021. Curcumin loaded chitosan nanoparticles fortify shrimp feed pellets with enhanced antioxidant activity. Materials Science & Engineering C 120. DOI: 10.1016/j.msec.2020.111737.##Chen, J., Chen, L., 2019. Effects of chitosan-supplemented diets on the growth performance, nonspecific immunity and health of loach fish (Misgurnus anguillicadatus). Carbohydrate Polymers 255. ##Dawood, M.A., Koshio S. and Esteban, M.Á., 2018. Beneficial roles of feed additives as immunostimulants in aquaculture: a review. Reviews in Aquaculture, 10: 950–974. DOI:10.1111/raq.12209. ##Du, Y., Hu, X., Miao, L., Chen, J., 2022. Current status and development prospects of aquatic vaccines. Frontiers in Immunology, 13: 1-21. DOI: 10.3389/fimmu.2022.1040336. ##Ellis, A. E., 1999. Fish immune system. In Encyclopedia of Immunology. Delves and I. M. Roitt, eds) pp: 920-926. London: Academic Press. ##El-Naggar, M., Medhat, F., Taha, A. 2022. Applications of chitosan and chitosan Aquaculture 289: 310-316. DOI: 10.1016/j.aquaculture.2009.02.001. ##Esmaeili Rad, A., Alishahi, M., Ghorbanpour M.M., Zarei, M., 2014. The effects of oral administration of extracted chitosan from white leg shrimp (Litopenaeus vannamei) on hematological and growth indices in common carp (Cyprinus carpio). Journal of Veterinary Research 69: 385-393. DOI: 10.22059/jvr.2014.52281. ##Geng, X., Dong, X.-H., Tan, B.-P., Yang, Q.-H., Chi, S.-Y., Liu, H.-Y., Liu, X.-Q., 2011. Effects of dietary chitosan and Bacillus subtilis on the growth performance, non-specific immunity and disease resistance of cobia, Rachycentron canadum. Fish Shellfish Immunol., 31, 400–406. doi.org/10.1016/j.fsi.2011.06.006.##Harikrishnan, R., Kim, J., Balasundaram, C., Heo, M. 2012. Immunomodulatory effects of chitin and chitosan enriched diets in Epinephelus bruneus against Vibrio alginolyticus infection. Aquaculture, 326: 46-52. DOI: 10.1016/j.aquaculture.2011. 11.034. ##Khani Oushani, A., Soltani, M., Sheikhzadeh, N., Shamsaie Mehrgan, M., Rajabi Islami, H., 2020. Effects of dietary chitosan and nano-chitosan loaded clinoptilolite on growth and immune responses of rainbow trout (Oncorhynchus mykiss). Fish Shellfish Immunol. 98: 210–217. https://doi.org/10.1016/j.fsi.2020.01.016##Ismael, Nahla E.M., Samah, A.A. Abd El-hameed, Amany, M., Salama Mohammed, A.E., Naiel, H., Abdel-Latif., M.R., 2021. The effects of dietary clinoptilolite and chitosan nanoparticles on growth, body composition, haemato-biochemical parameters, immune responses, and antioxidative status of Nile tilapia exposed to imidacloprid. & quot. Environmental Science and Pollution Research, 28: 29535- 29550. 10.1007/s11356-021-12693-4 ##Li, R., Wang, X., Yu, D., Liang, Q., Liu, F., Zhang, L., Hu, B., Wei, J., Liu, L., Liu, J., Xu, H., 2023. Dietary chitosan alleviates intestinal and liver injury of hybrid sturgeon (Acipenser baerii♀ × A. schrenckii♂) induced by Aeromonas hydrophila infection. Anim. Feed Sci. Technol. 299, 115624. https://doi.org/10.1016/j.anifeedsci.2023.115624##Li, S.T., Young, H.T., Wang, C.T., Huang, T.W., 2018. Chitosan films promote formation of olfactory neurospheres and differentiation of olfactory receptor neurons, Rhinology, 56: 336–342. DOI: 10.4193/Rhin17.155. ##Lin, S., Mao, S., Guan, Y., Luo, Lin, Luo, Li, Pan, Y., 2012. Effects of dietary chitosan oligosaccharides and Bacillus coagulans on the growth, innate immunity and resistance of koi (Cyprinus carpio koi). Aquaculture 342–343, 36–41. https://doi.org/10.1016/j.aquaculture.2012.02.009. ##Matsuyama, H., Tanaka, K., Nakao, M., Yano, T. 1988. Characterization of the alternative complement pathway of carp. Developmental and Comparative Immunology, 12: 403-408. ##Mohseni, M., Pourali, H.R., Kazemi, R., Bai, Sunhchal C., 2014. Evaluation of the optimum dietary protein level for the maximum growth of juvenile beluga (Huso huso L. 1758). Aquaculture, 45: 1832–1841. ##Mohseni, M., Ghelichpour, M., Sayed Hassani, M.H., Pajand, Z., Ghorbani Vaghei, R.m 2023. Efficacy of dietary thiamine supplementation on growth performance, digestive enzymes, immunological responses, and antioxidant capacity of juvenile beluga (Huso huso). Aquaculture Reports, 31: 1-8. ##Qin, C., Zhang, Y., Liu, W., Xu, L., Yang, Y., Zhou, Z., 2014. Effects of chito-oligosaccharides supplementation on growth performance, intestinal cytokine expression, autochthonous gut bacteria and disease resistance in hybrid tilapia Oreochromis niloticus ♀ × Oreochromis aureus ♂. Fish Shellfish Immunol., 40: 267–74. https://doi.org/10.1016/j.fsi.2014.07.010##Salam, M.A., Das, T.R., Paul, S.I., Islam, F., Baidya, A., Rahman, M.L., Shaha, D.C. and Mazumder, S.K., 2024. Dietary chitosan positively influences the immunity and reproductive performances of mature silver barb (Barbonymus gonionotus). Aquaculture Reports, 36: p.102155.##Salam, Mohammad Abdus, M.d. Ashikur Rahman, Sulav Indra Paul, Fatama Islam, Avishek Kanti Barman, Zinia Rahman, Dinesh Chandra Shaha, Md Mahbubur Rahman, and Tofazzal Islam., 2021. Dietary chitosan promotes the growth, biochemical composition, gut microbiota, hematological parameters and internal organ morphology of juvenile Barbonymus gonionotus. & quot. PLoS One., 16 (11): e0260192. ##Siwicki, A.K., Anderson, D.P., Rumsey, G.L., 1994. Dietary intake of immunostimulants by rainbow trout affects non-specific immunity and protection against furunculosis. Vet Immunol Immunopathol, 41(1-2):125-39. ##Subramanian S, MacKinnon SL, Ross NW. A., 2007. comparative study on innate immune parameters in the epidermal mucus of various fish species. Comp Biochem Physiol B Biochem Mol Biol., 148(3): 256-263.##Wang, W., Sun, J., Liu, C. and Xue, Z., 2017. Application of immunostimulants in aquaculture: Current knowledge and future perspectives. Aquaculture Research, 48:1–23. DOI: 10.1111/are.13161.##Wu, S., 2020. The growth performance, body composition and nonspecific immunity of Tilapia (Oreochromis niloticus) affected by chitosan. Int J Biol Macromol., 145: 682–685. https://doi.org/10.1016/j.ijbiomac.2019.12.235. ##Xu, Q.S., Wang, W.J., Yang, W., Du, Y.G., Song, L.S., 2017. Chitosan oligosaccharide Inhibits EGF-induced cell growth possibly through blockade of epidermal growth factor receptor/mitogen-activated protein kinase pathway, Int. J. Biol. Macromol., 98: 502–505. 10.1016/j.ijbiomac.2017.02.021. ##Xu, H., Wang, X., Liang, Q., Xu, R., Liu, J., Yu, D., 2023. Dietary chitosan moderates the growth rate, antioxidant activity, immunity, intestinal morphology and resistance against Aeromonas hydrophila of juvenile hybrid sturgeon (Acipenser baerii♀ × Acipenser schrenckii♂). Int. J. Biol. Macromol. 224, 1012–1024. https://doi.org/10.1016/j.ijbiomac.2022.10.185##Yan, J., Guo, C., Dawood, M., Gao, J., 2017. Effects of dietary chitosan on growth, lipid metabolism, immune response and antioxidant-related gene expression in Misgurnus anguillicaudatus. Benef Microbes 8(3):439-449. https://doi.org/10.3920 / BM2016.0177. ##Younus, N., Zuberi, A., Mahmoood, T., Akram, W., Ahmad, M., 2020. Comparative effects of dietary micro- and nano-scale chitosan on the growth performance, non-specific immunity, and resistance of silver carp Hypophthalmichthys molitrix against Staphylococcus aureus infection. Aquac. Int. 28, 2363–2378. https://doi.org/10.1007/s10499-020-00595-0##Zakeri, D., Pazooki, J., Mohseni, M. and Jamshidi, S.H. 2023. Effect of dietary chitosan on the growth performance, intestinal histology and growth‐related gene expression in stellate sturgeon (Acipenser stellatus) juveniles. Journal of Animal Physiology and Animal Nutrition, 108 (4):1152-1163. DOI: 10.1111/jpn.13961. ##Zhang, P., Liu, W.Z., Peng, Y.F., Han, B.Q., Yang, Y., 2014. Toll like receptor 4 (TLR4) Mediates the stimulating activities of chitosan oligosaccharide on macrophages, Int. Immunopharmacol., 23: 254–261. 10.1016/j.intimp.2014.09.007 .##Zhang, Q., Xie, Y., Tang, J., Meng, L., Huang, E., Liu, D., Tong, T., Liu, Y. and Guo, Z., 2024. Effects of Dietary Chitosan on Growth Performance, Serum Biochemical Indices, Antioxidant Capacity, and Immune Response of Juvenile Tilapia (Oreochromis niloticus) under Cadmium Stress. Animals: An Open Access Journal from MDPI, 14(15). doi.org/10.3390/ani14152259.## ##

مقاله علمی – پژوهشی:‌ تاثیر نوع حلال بر میزان بازده استخراج و خواص آنتی‌اکسیدانی پلی‌فنول‌ها و آلژینات از جلبک‌های قهوه‌ای Sargassum cristaefolium و Nizimudinia zanardinii جمع‌آوری شده از سواحل شمالی دریای عمان Effect of solvent type on extraction efficiency and antioxidant properties of polyphenols and alginate from brown seaweeds Sargassum cristaefolium and Nizimudinia zanardinii collected from the northern coasts of the Oman Sea 1 1 در مطالعه حاضر تاثیر نوع حلال بر میزان بازده استخراج و خواص آنتی‌اکسیدانی پلی‌فنول‌ها و آلژینات استخراجی از جلبک‌های قهوه‌ای Sargassum cristaefolium و Nizimudinia zanardinii جمع‌آوری شده از سواحل شمالی دریای عمان مورد بررسی قرار گرفت. جلبک‌های قهوه‌ای از سواحل چابهار جمع‌آوری، شستشو و در سایه خشک گردید. در ادامه استخراج عصاره از جلبک‌ها با استفاده از حلال‌های متانول (100، 70 و 30 درصد)، اتیل استات (100، 70 و 30 درصد ) و آب (100 درصد) انجام شده و میزان استخراج عصاره، میزان فلوروتانین، توانایی مهار رادیکال آزاد DPPH و توانایی کلاته‌کنندگی مس در عصاره‌های مختلف سنجش گردید. نتایج نشان داد که نوع حلال (متانول یا اتیل استات) و نسبت ترکیب آن (70، 30 و صفر درصد) با آب تآثیر زیادی بر میزان استخراج عصاره، فلوروتانین، آلژینات و خواص آنتی‌اکسیدانی آنها دارد. در هر دو جلبک، حلال‌های آلی در شکل خالص کارایی بهتری نسبت به شکل ترکیب با آب داشتند. نتایج مقایسه دو جلبک نیز نشان داد که جلبک N. zanardinii نسبت به S. cristaefolium دارای میزان فلوروتانین، آلژینات و خواص آنتی‌اکسیدانی بالاتری بوده است. بنابراین، از جلبک N. zanardinii و عصاره حاصل از حلال متانول 100 درصد برای استخراج فلوروتانین و در ادامه آلژینات استفاده گردید. نتایج ادامه پژوهش نشان داد که در فرکشن‌های مختلف حاصله از عصاره اولیه جلبک N. zanardinii،، فرکشن اتیل‌استاتی دارای میزان فلوروتانین، مهار رادیکال آزاد و کلاته‌کنندگی یون مس بالاتری نسبت به سایر فرکشن‌‌ها بوده است. به طور کلی، نتایج حاصل از این پژوهش نشان داد که نوع حلال تاثیر معنی‌داری بر میزان استخراج ترکیبات فنولی و آلژینات از جلبک قهوه‌ای دارد و میزان این ترکیبات و خواص آنتی‌اکسیدانی آنها بسته به نوع گونه و شرایط استخراج متفاوت است. 2 Introduction Among all marine organisms, seaweeds are considered as one of the sources of bioactive compounds. The most important compounds found in brown seaweed include phenolic compounds, polysaccharides, polyunsaturated fatty acids, proteins, peptides, pigments, vitamins, terpenoids and sterols (Sadeghi et al., 2023). Phlorotannins are compounds containing a benzene ring with one or more hydroxyl group substitutions, which are found only in brown seaweeds. So far, more than 150 algal polyphenol structures have been reported (Asaduzzaman et al., 2020). Reports indicate that these compounds have several medicinal properties such as antimicrobial and antioxidant (Milledge et al., 2015). Phycocolloids or hydrocolloids are another group of bioactive compounds found in brown seaweeds. The most important hydrocolloids found in seaweeds include alginate, agar, and carrageenan (Cmikova et al., 2022). Sargassum cristaefolium and Nizimudinia zanardinii are brown seaweeds species with good distribution on the southern coasts of Iran that can be considered as potential options for investigating the presence of compounds with antioxidant and functional properties. Therefore, the objectives of the present study included 1) extraction of bioactive compounds (including phenolic compounds and alginate) using different solvents and 2) investigation of the extraction efficiency and antioxidant properties of the extracted compounds. Methodology Brown seaweeds S. cristaefolium and N. zanardinii were collected from the Chabahar coast, washed and dried in the shade. Extraction was performed using methanol (100%, 70%, 30%), ethyl acetate (100%, 70%, 30%) and water (100%) and the extraction yield, phlorotannins content, DPPH free radical scavenging activity and copper chelating ability of different extracts were measured. To purify phenolic compounds in N. zanardinii, the methanol extract was fractionated using chloroform, dichloromethane and ethyl acetate solvents. Alginate was extracted using distilled water and the residue obtained from the extraction in the previous section was used for extraction. Total phenol content was measured based on the standard phloroglucinol (PHG) and using the Folin-Ciocalteu indicator. DPPH free radical scavenging activity was measured according to the method of Shimada et al. (1992). Cupric chelating ability of different extracts was measured according to the method mentioned by Wong et al. (2006). Results In S. cristaefolium, among the different treatments, the highest extraction yield was obtained in 70% methanol solvent (5.50 g/100 g), while in N. zanardinii the highest yield was in 100% methanol solvent and equal to 43.6 g/100 g seaweed. The extract yield in N. zanardinii was higher than S. cristaefolium in most treatments. In both seaweeds, the highest phlorotannins content was observed in 100% ethyl acetate treatment and the lowest in 100% water treatment. The highest DPPH scavenging activity was obtained in 100% ethyl acetate treatment of N. zanardinii at 84.38%. The lowest DPPH scavenging activity was observed in 100% water extract. Among the different fractions, the highest extraction yield by weight was associated with the ethyl acetate fraction (2.54 g). The highest amount of phlorotannins, i.e. 19.14 mg phloroglucinol/g extract, was found in the ethyl acetate fraction, while the lowest amount (1.35 mg PHG/g) was found in the chloroform fraction. The highest radical scavenging activity, 98.95%, was found in the ethyl acetate fraction. When comparing the fractions with the first extract, only the cupric chelation rate in the ethyl acetate fraction (73.44%) was higher than in the first extract (43.45%), and lower chelating ability was observed in the other fractions. Discussion and Conclusion In the present study, organic solvents in pure form were more effective than those mixed with water in both S. cristaefolium and N. zanardinii. These results are in agreement with the study of El-Sheekh et al. (2023) who reported that the extraction yield and antioxidant properties varied depending on the type of solvent and ... 67 81 2023/12/232024/12/242025/02/22024/10/122025/01/23 1403/11/4 2025/02/282025/02/282025/02/282025/02/282025/02/28 1403/12/10 سلیم شریفیان Salim Sharifian دانشگاه دریانوردی و علوم دریایی چابهار Iran sharifian.salim@hotmail.com ملیکا ناظمی Melika Nazemi پژوهشکده اکولوژی خلیج فارس و دریای عمان، موسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی، بندرعباس Iran melikanazemi@yahoo.com Polyphenols Alginate Brown Seaweeds Oman Sea پلی‌فنول‌ها آلژینات جلبک‌های قهوه‌ای دریای عمان Asaduzzaman, A.K.M., Hasan, I., Rahman, M.H. and Tareq, A.R.M., 2020. Antioxidant and antiproliferative activity of phytoconstituents identified from Sargassum binderi seaweed extracts cultivated in Bangladesh. International Journal of Biosciences, 16(3): 481-494. Doi: 10.12692/ijb/16.3.481-494##Afrin, F., Ahsan, T., Mondal, M.N., Rasul, M.G., Afrin, M., Silva, A.A., Yuan, C. and Shah, A.K.M.A., 2023. Evaluation of antioxidant and antibacterial activities of some selected seaweeds from Saint Martin's Island of Bangladesh. Food Chemistry Advances, 3: 100393. https://doi.org/10.1016/j.focha.2023.100393.##Bojorges, H., Lopez-Rubio, A., Martinez-Abad, A. and Fabra, M.J., 2023. Overview of alginate extraction processes: Impact on alginate molecular structure and techno-functional properties. Trends in Food Science & Technology, 140: 104142. https://doi.org/10.1016/j.tifs.2023.104142##Chakraborty, K., Joseph, D. and Praveen, N.K., 2015. Antioxidant activities and phenolic contents of three red seaweeds (Division: Rhodophyta) harvested from the Gulf of Mannar of Peninsular India. Journal of Food Science and Technology, 52(4): 1924-1935. DOI 10.1007/s13197-013-1189-2##Chan, P.T., Matanjun, P., Yasir, S.M. and Tan, T.S., 2015. Antioxidant activities and polyphenolics of various solvent extracts of red seaweed, Gracilaria changii. Journal of Applied Phycology, 27: 2377-2386. https://doi.org/10.1007/s10811-014-0493-1##Cmikova, N., Galovicova, L., Miskeje, M., Borotova, P., Kluz, M. and Kacaniova, M., 2022. Determination of antioxidant, antimicrobial activity, heavy metals and elements content of seaweed extracts. Plants, 11(11): 1493. https://doi.org/10.3390/plants11111493##Cotas, J. Leandro, A. Monteiro, P. Pacheco, D. Figueirinha, A. and Gonçalves, A.M.., 2020. Seaweed phenolics: from extraction to applications, Marine Drugs, 18: 384, https://doi.org/10.3390/md18080384.##El-Sheekh, M.M., Bases, E., El Shafay, S.M. and El-shenody, R., 2023. Influence of Seasonal Variations on Extract Yield and Antioxidant Activities of Some Seaweed Species. Proceedings of the National Academy of Sciences, India Section B: Biological Sciences, 93: 915–923. https://doi.org/10.1007/s40011-023-01493-0 ##Emu, S.A., Dual, M.A., Kali, T.D., Ghadni, M.S., Rasul, M.G., Mondal, M.N., Ahsan, M.E., Khan, M. and Shah, A.K.M.A., 2023. Effects of extracting solvents on phytochemical, antioxidant, and antibacterial activity of some seaweeds from the Bay of Bengal offshore Island. Food and Humanity, 1: 1157–1166. https://doi.org/10.1016/j.foohum.2023.09.005##Gall, E.A., Lelchat, F., Hupel, M., Jegou, C. and Stiger-Pouvreau, V., 2015. Extraction and Purification of Phlorotannins from Brown Algae. Methods in Molecular Biology, 1308: 131-143. doi:10.1007/978-1-4939-2684-8_7##Gharekhan Taghar Tapeh, R., Kordjazi, M. , Ahmad Nasrollahi, S. , Shabanpour, B. and Adeli, A., 2020. Investigation of antioxidant properties and antibacterial activity of alginate and fucoidan extracted from Sargassum boveanum algae collected from the Persian Gulf coast. Aquaculture Sciences, 7(2), 64-76. (In Persian)##Jayakody, M.M., Vanniarachchy, M.P.G. and Wijesekara, I., 2020. Seaweed derived alginate, agar, and carrageenan based edible coatings and films for the food industry: a review. Food Measure, 16: 1195–1227. https://doi.org/10.1007/s11694-021-01277-y##Kwon, T.H., Kim, T.W., Kim, C.G. and Park, N.H., 2013. Antioxidant Activity of Various Solvent Fractions from Edible Brown Algae, Eisenia bicyclisand Its Active Compounds. Journal of Food Science, 78(5): C679–C684. doi:10.1111/1750-3841.12109##Lashkan, A.B., Rezaei, M., Rezaei, K. and Seifabadi, S.J., 2012. Optimization of Extraction of Antioxidant Compounds in Microwave-Assisted Extracts of Brown Algae Sargassum angustifolium. Journal of Fisheries, Iranian Journal of Natural Resources. 65(3): 243-255.##Liu, X., 2015. Extraction and Antioxidant Activity of Phlorotannins from Edible Brown Algae. Master thesis, North Carolina State University. 127 p. ##Maqsood, S., Benjakul, S. and Shahidi, F., 2013. Emerging role of phenolic compounds as natural food additives in fish and fish products. Critical Review in Food Science and Nutrition. 53:162-79.##Milledge, J.J., Nielsen, B.V. and Bailey, D., 2015. High-value products from macroalgae: the potential uses of the invasive brown seaweed, Sargassum muticum. Reviews in Environmental Science and Biotechnology. DOI: 10.1007/s11157-015-9381-7##Mohammad Nejad Khiavi, N., Eghbal, H., Jahani, N., Ahmadi Sabegh, M. and Ghazi Tabatabaei, Z. 2020. Investigating the importance and role of Seaweeds in Industry and their Pharmaceutical and Environmental applications. The Application of Chemistry in Environment, 40, 9-17.##Rostami Z., Tabarsa M., You S. and Rezaei M., 2017. Relationship between molecular weights and biological properties of alginates extracted under different methods from Colpomenia peregrina. Process Biochemistry, 58: 289-297.##Sadeghi, A., Rajabiyan, A., Nabizade, N., Meygoli Nezhad, N. and Zarei Ahmady, A., 2024. Seaweed-derived phenolic compounds as diverse bioactive molecules: A review on identification, application, extraction and purification strategies. International Journal of Biological Macromolecules, 266: 131147. https://doi.org/10.1016/j.ijbiomac.2024.131147##Sasadara, M.M.V. and Wirawan, I.G.P., 2021. Effect of extraction solvent on total phenolic content, total flavonoid content, and antioxidant activity of Bulung Sangu (Gracilaria sp.) Seaweed. 3rd international conference on bioscience and biotechnology, IOP Conf. Series: Earth and Environmental Science, 712, 012005. doi:10.1088/1755-1315/712/1/012005##Shimada, K., Fujikawa, K., Yahara, K. and Nakamura, T., 1992. Antioxidative properties of xanthan on the autoxidation of soybean oil in cyclodextrin emulsion. Journal of Agriculture and Food Chemistry. 40: 945-948. DOI: 10.1021/jf00018a005##Singleton, V.L., Orthofer, R. and Lamuela-Raventos, R.M., 1999. Analysis of total phenols and other oxidation substrates and antioxidants by means of Folin-Ciocalteu Reagent. Methods in Enzymology. 299:152-178. DOI: 10.1016/S0076-6879(99)99017-1##Subbiah, V., Xie, C., Dunshea, F.R., Barrow, C.J. and Suleria, H.A.R., 2022. The quest for phenolic compounds from seaweed: nutrition, biological activities and applications. Food Reviews International, 2094406.. https://doi.org/10.1080/87559129.2022.2094406##Sobuj, M.K.A., Islam, M., Mahmud, Y. and Rafiquzzaman, S.M., 2021. Effect of solvents on bioactive compounds and antioxidant activity of Padina tetrastromatica and Gracilaria tenuistipitata seaweeds collected from Bangladesh. Scientific Reports, 11(1): 1-13. DOI: 10.21203/rs.3.rs-557313/v1.##Taheri, A., 2016. Antioxidant activity in some Iranian seaweed species from Chabahar. Iranian Journal of Fisheries Sciences, 15(2): 802-817.##Thanigaivel, S., Vidhya Hindu, S., Vijayakumar, S., Mukherjee, A., Chandrasekaran, N. and Thomas, J., 2015. Differential solvent extraction of two seaweeds and their efficacy in controlling Aeromonas salmonicida infection in Oreochromis mossambicus: A novel therapeutic approach. Aquaculture, 443: 56–64. doi:10.1016/j.aquaculture.2015.03.##Wong, S.P., Leong, L.P. and William Koh, J.H., 2006. Antioxidant activities of aqueous extracts of selected plants. Food Chemistry, 99(4): 775-783.##Yalçın, S., Uzun, M., Karakaş, Ö., Sözgen Başkan, K., Okudan, E. Ş. and Apak, M.R., 2020. Determination of Total Antioxidant Capacities of Algal Pigments in Seaweed by the Combination of High-Performance Liquid Chromatography (HPLC) with A Cupric Reducing Antioxidant Capacity (CUPRAC) Assay. Analytical Letters, 1–20. doi:10.1080/00032719.2020.1855439## ##

مقاله علمی – پژوهشی:‌ شاخص‌های رشد و محتوای اسیدهای چرب عضله ماهی قزل‌آلای رنگین‌کمان (Oncorhynchus mykiss) تغذیه شده با خوراک کاملاً گیاهی حاوی سطوح مختلف اسیدهای چرب تک غیر اشباع و نسبت‌های لینولئیک اسید به لینولنیک اسید Growth indices and muscle fatty acid content of rainbow trout (Oncorhynchus mykiss) fed whole plant meal diet contained different levels of monounsaturated fatty acids and linoleic acid to linolenic acid ratios 1 1 افزایش جهانی تولیدات آبزی‌پروری باعث افزایش نیاز به روغن ماهی جهت تولید خوراک آبزیان پرورشی شده است. استفاده از روغن گیاهی به جای روغن ماهی، سبب افزایش پایداری تولید آبزی‌پروری و افزایش سوددهی مزارع پرورش آبزیان می‌‌شود. مطالعه حاضر برای ارزیابی اثر سطوح مختلف اسیدهای چرب تک غیر اشباع (25 و 55 درصد) خوراک با نسبت‌های مختلف لینولئیک اسید (LA): لینولنیک اسید (ALA) (1، 2 و 8) در خوراک فاقد پودر و روغن ماهی بر عملکرد رشد و الگوی اسیدهای چرب عضله ماهی قزل‌آلای رنگین‌کمان (Oncorhynchus mykiss) مورد بررسی قرار گرفت. تعداد 650 قطعه ماهی قزل‌آلای رنگین‌کمان تریپلوئید با وزن متوسط 17/0± 5/14 گرم به صورت تصادفی میان 7 تیمار آزمایشی با 3 تکرار در مخازن پلی اتیلنی 300 لیتری توزیع شدند. ماهیان به مدت 4 ماه با جیره‌های آزمایشی تغذیه شدند. پس از طی این مدت، گروه‌های مختلف آزمایشی به مدت یک ماه نیز با جیره پایانی که دارای روغن ماهی بود، تغذیه شدند. شاخص‌های رشد ماهیان گروه‌های مختلف آزمایشی در پایان هر دو دوره فاقد تفاوت آماری معنی‌دار بود (05/0p>). نسبت اسیدهای چرب چندغیراشباع سری3 n-به سری6 n- (n-6 PUFA/n-3PUFA) عضله ماهی در هر دو دوره در تیمار 5 (ماهیان تغذیه شده با خوراک حاوی 55 درصد MUFA و نسبت LA:ALA برابر 8) نسبت به تیمار شاهد به طور معنی‌داری افزایش یافت (05/0p<). در دوره اول پرورش محتوای دوکوزاهگزانوئیک اسید (DHA)، ایکوزاپنتانوئیک اسید (EPA) و اسیدهای چرب چندغیراشباع (PUFA) عضله ماهیان همه تیمارها نسبت به گروه شاهد کاهش معنی‌داری داشت (05/0p<). تغذیه پایانی با جیره حاوی روغن ماهی توانست محتوای اسیدهای چرب مذکور را در عضله ماهیان بازسازی نماید، البته محتوای DHA عضله ماهیان تیمار 5 نسبت به گروه شاهد به طور معنی‌داری پایین بود (05/0p<). نتایج مطالعه حاضر نشان داد که ترکیب مناسب روغن‌های گیاهی بدون اثر منفی بر رشد ماهیان حتی تا وزن قابل ارائه به بازار می‌تواند جایگزین روغن ماهی شود. همچنین می‌توان با استفاده از یک دوره تغذیه پایانی کوتاه‌مدت با خوراک حاوی روغن ماهی، محتوای اسیدهای چرب عضله ماهیان را برای افزایش ارزش غذایی آن بازسازی نمود. 2 Introduction During the previous couple of decades, the world aquaculture industry has considerably developed and remained one of the fastest-growing food-producing sectors. The global increase in aquaculture production has resulted in increased worldwide demand for fish oil to meet ever developing aquafeed industry. It has been shown that terrestrial lipid sources including vegetable oils are promising alternatives for dietary fish oil due to their increased production, price stability, and availability. Incorporating vegetable oil instead of fish oil in aquafeed formulation could improve the sustainability of aquaculture development and also increase the profitability of aquaculture industry (Xie et al., 2018; FAO, 2020). The present research was conducted to elucidate the effects of different dietary MUFA contents and LA:ALA ratios, by dietary incorporation of different propositions of vegetable oils including sunflower, linseed, coconut and olive oils instead of fish oil on growth indices and muscle fatty acids profile of Oncorhynchus mykiss fed on a plant-based diet without any marine ingredients. Methodology This study was conducted to evaluate the effect of different dietary levels of MUFA and different ratios of linoleic acid (LA) to linolenic acid (ALA) on growth performance and muscle fatty acid profile of rainbow trout fingerlings. 650 juveniles of triploid rainbow trout with an average initial body weight of 14.5 ± 0.17 g were randomly allocated into seven triplicated experimental groups in 300-liter polyethylene tanks. Therefore, seven iso-nitrogenous and iso-lipid experimental diets including diet 1 (55.33, 1.00; dietary MUFA content and LA:ALA ratio), diet 2 (25.30, 1.00), diet 3 (55.13, 2.05), 4 (24.92, 2.03), diet 5 (54.94, 8.06) and diet 6 (24.91, 8.06) and a control diet containing fish oil, diet 7 (33.60, 5.97) were formulated. The basal diet did not contain any fish meal. The experimental fish were fed the diets for 4 months during the first stage of the trial. Afterwards, during the second stage of the trial, all experimental groups were fed diet 7, the basal diet which contained fish oil as the only dietary lipid source for one month. At the end of each stage, the fish were weighed to the nearest 0.1 g to calculate growth indices. Muscle samples were also taken after humanly sacrificing fish for fatty acid profile studies. Results At the end of the first four-month feeding period, there was no significant difference among various experimental groups regarding weight gain (WG), relative WG, daily weight gain (DWG), specific growth rate (SGR), and survival rate (p>0.05). Similarly, feeding various experimental groups with diet containing only fish oil as the only dietary lipid source for one month also did not result in any significant differences among the groups (p>0.05). At the end of the first stage, there were no significant differences regarding muscle SFA contents of various experimental groups (p>0.05). Muscle MUFA contents reflected dietary MUFA content so that the highest MUFA proposition was observed in treatment 1 (p<0.05). However, n-6 PUFA and n-6 HUFA contents of fish in treatments 5 and 6 fed diets contained the highest dietary LA:ALA ratio (i.e., 8.0) was the highest (p<0.05). Muscle n-3 HUFA contents of the fish fed diets with lower dietary LA:ALA diet (≤2.0) were considerably higher than treatments 5 and 6 (p<0.05). However, those fish fed with diet 7 showed the highest muscle n-6 HUFA content (p<0.05). At the end of the first experimental period, muscular contents of EPA, DHA and PUFA of all experimental groups were significantly decreased (p<0.05) comparing to those fish fed diet containing fish oil (treatment 7). At the end of the both periods, muscle n-6 PUFA/n-3PUFA was significantly increased in treatment 5 (fish fed diet containing 55% MUFA and LA:ALA ratio of 8) compared to the control group (treatment 7, p<0.05). At the end of the second feeding period, there were no significant differences regarding muscle SFA and PUFA contents among various experimental groups (p>0.05). Similar to the previous stage, muscle MUFA contents of those fish that had previously been fed diets with higher MUFA contents was higher but the difference was milder compared to the first feeding period. Muscle n-3 PUFA and n-3 HUFA contents of fish did not show any differences among various experimental groups (p>0.05). However, muscle C20:4n-6, n-6 PUFA and n-6 HUFA contents still showed significant differences among groups to the extent that treatments 5 and 6 showed the highest propositions (p<0.05). Feeding all experimental groups with the finisher diet containing fish oil could to some extent restore the muscular contents of the aforementioned fatty acids, although muscle DHA content of treatment 5 was significantly lower compared to treatment 7 (p<0.05). Discussion and conclusions Our results showed that different vegetable oils blends could replace fish oil in plate-sized rainbow trout feed. Complete replacement of dietary fish oil by such terrestrial oils blends with different MUFA contents and LA:ALA ratios could affect muscle fatty acid profiles of fish which were characterized by high MUFA, ArA, and LA and lower EPA and DHA contents when compared to those fish fed diet containing fish oil. Although, rainbow trout was considerably able to de novo synthesis of EPA and DHA, increasing dietary LA:ALA ratio, i.e., >2.0, resulted in decreased muscle EPA and DHA content revealing that increased dietary LA:ALA ratio might affect liver desaturation and elongation enzymes activity which finally affect muscle fatty acid deposition requiring further studies regarding the enzymes activity and expression. Such decreased EPA and DHA contents warrant further consideration in terms of the nutritional quality of fish fillet for human consumption when replacing dietary fish oils with vegetable oils. In addition, feeding the fish with a finisher diet contained fish oil for a short period could restore the muscular fatty acids profile to improve the nutritional quality of fish. The efficacy of such a feeding strategy was considerably higher in those fish previously been fed diet 2 contained 25% MUFA with LA:ALA ratio of 1.0. However, the complete conclusion warrants more detailed studies in in terms of nutrient digestion and absorption, immune competence and finally reproductive performance of fish. Conflict of Interest The authors declare that they have no conflict of interest. Acknowledgment We are grateful to the technicians and staff of the Fisheries Department of Natural Resources Faculty and Artemia and Aquaculture Research Institute, Urmia University for their sincere assistance during the experiment.   83 97 2023/12/232024/12/242025/02/22024/10/122025/01/232024/10/15 1403/7/24 2025/02/282025/02/282025/02/282025/02/282025/02/282025/02/28 1403/12/10 زهرا محمودی کیا Zahra Mahmoudikia دانشگاه ارومیه Iran mahmoudi.kiya2014@gmail.com احمد ایمانی Ahmad Imani دانشگاه ارومیه Iran a.imani@urmia.ac.ir رامین مناف فر Ramin Manaffar دانشگاه ارومیه Iran r.manaffar@urmia.ac.ir فرزانه نوری Farzaneh Noori دانشگاه ارومیه Iran f.noori@urmia.ac.ir رضا جلیلی Reza Jalili دانشگاه ارومیه Iran re.jalili@gmail.com feed vegetable oil fatty acids growth indices rainbow trout خوراک روغن گیاهی اسید‌های‌چرب شاخص‌های رشد قزل‌آلای‌رنگین‌کمان Arslan, M., Sirkecioglu, N., Bayir, A., Arslan, H., Aras, M., 2012. The influence of substitution of dietary fish oil with different vegetable oils on performance and fatty acid composition of brown trout, Salmo trutta. Turkish Journal of Fisheries and Aquatic Sciences, 12(3).‌ DOI:10.4194/1303-2712-v12_3_04.##Bell, J. G., McEvoy, J., Tocher, D. R., McGhee, F., Sargent, J. R., Campbell, P. J., 2001. Replacement of fish oil with rapeseed oil in diets of Atlantic salmon (Salmo salar) affects tissue lipid compositions and hepatocyte fatty acid metabolism. The Journal of nutrition, 131(5), 1535-1543. DOI: 10.1093/jn/131.5.1535.##Bell, J. G., Henderson, R. J., Tocher, D. R., Sargent, J. R., 2004. Replacement of dietary fish oil with increasing levels of linseed oil: modification of flesh fatty acid compositions in Atlantic salmon (Salmo salar) using a fish oil finishing diet. Lipids, 39, 223-232.‌ DOI:10.1007/s11745-004-1223-5.##Benítez-Dorta, V., Caballero, M. J., Izquierdo, M., Manchado, M., Infante, C., Zamorano, M. J., Montero, D., 2013. Total substitution of fish oil by vegetable oils in Senegalese sole (Solea senegalensis) diets: effects on fish performance, biochemical composition, and expression of some glucocorticoid receptor-related genes. Fish Physiology and Biochemistry, 39, 335-349.‌ DOI: 10.1007/s10695-012-9703-4.##Caballero, M. J., Obach, A., Rosenlund, G., Montero, D., Gisvold, M., Izquierdo, M. S., 2002. Impact of different dietary lipid sources on growth, lipid digestibility, tissue fatty acid composition and histology of rainbow trout, Oncorhynchus mykiss. Aquaculture, 214(1-4), 253-271.‌ doi:10.1016/S0044-8486(01)00852-3.##Chen, C. Chen, J. Wang, S. You, C. Li, Y., 2017. Effects of different dietary ratios of linolenic to linoleic acids or docosahexaenoic to eicosapentaenoic acids on the growth and immune indices in grouper, Epinephelus coioides. Aquaculture 473 (2017) 153–160. DOI:10.1016/j.aquaculture.2017.02.010.##Dernekbasi, S., Akyuz, A. P., Karayucel, İ., 2021. Effects of total replacement of dietary fish oil by vegetable oils on growth performance, nutritional quality and fatty acid profiles of rainbow trout (Oncorhynchus mykiss) at optimum-and high temperature conditions. Ege Journal of Fisheries and Aquatic Sciences, 38(2), 237-246.‌ DOI:10.12714/egejfas.38.2.14.##Drew, M. D., Ogunkoya, A. E., Janz, D. M., Van Kessel, A. G., 2007. Dietary influence of replacing fish meal and oil with canola protein concentrate and vegetable oils on growth performance, fatty acid composition and organochlorine residues in rainbow trout (Oncorhynchus mykiss). Aquaculture, 267(1-4), 260-268. DOI:10.1016/j.aquaculture.2007.01.002.##Eroldogan, T., Turchini, G. M., Yılmaz, A. H., Taşbozan, O., Engin, K., Olculu, A., Ozsahinoglu1, I., Mumogullarında, P., 2012. Potential of Cottonseed Oil as Fish Oil Replacer in European Sea Bass Feed Formulation. Turkish Journal of Fisheries and Aquatic Sciences 12, 787-797. DOI: 10.4194/1303-2712-v12_4_07.##FAO. 2020. The state of world fisheries and aquaculture 2020. Sustainability in action. Rome. https://doi.org/10.4060/ca9229en.##FAO. (2024). Report: Global fisheries and aquaculture production reaches a new record high. Aquaculture surpasses capture fisheries in aquatic animal production for the first time, The State of World Fisheries and Aquaculture 2024 says. https://doi.org/10.4060/cd0683en.##Guler, M., Yildiz, M., 2011. Effects of dietary fish oil replacement by cottonseed oil on growth performance and fatty acid composition of rainbow trout (Oncorhynchus mykiss). Turkish Journal of Veterinary & Animal Sciences, 35(3), 157-167.‌ DOI:10.3906/vet-1002-252.##Hardy, R. W., 2000. New developments in aquatic feed ingredients, and potential of enzyme supplements. Avances en Nutrición Acuicola.‌ 19-22.##Jalali, S. M. A., Kiani, M., Jalali, S. A. H., Pourreza, J. (2019). The effect of replacement of fish oil by soybean or canola oils with L-carnitine supplement on growth performance of rainbow trout, oncorhynchus mykiss. (in Persian).‌ DOI: 10.22059/JVR.2019.216668.2522.##Karayücel, İ., and Dernekbaşı, S., 2010. Effect of dietary canola oil level on growth, feed utilization, and body composition of rainbow trout (Oncorhynchus mykiss L.). Israeli Journal of Aquaculture Bamidgeh, 62(3), 155-162.‌ http://www.siamb.org.il.##Lee, C.S. and Donaldson, E. M., 2001. General discussion on reproductive biotechnology in finfish aquaculture. Aquaculture, Vol. 197: 303-320.DOI: 10.1016/s0044-8486(01)00591-9.##Lepage, G and Roy, C. C., 1984. Improved recovery of fatty acid through direct transesterification without prior extraction or purification. Journal Lipid Research 25, 1391–1396. https://doi.org/10.1016/S0022-2275(20)34457-6.##Martinez, J. L, Petranovic, D, Nielsen, J., 2016. Heme metabolism in stress regulation and protein production: From Cinderella to a key player. Bioengineered 7(2):112-5. DOI: 10.1080/21655979.2015.1126016.##‌Marotta Lima, B. T. Takahashi, N. S. Tabata, Y. A. Shohei Hattori, R. Silva Ribeiro, C. D. Guimarães Moreira. R., 2019. Balanced omega-3 and -6 vegetable oil of Amazonian sacha inchi act as LC- PUFA precursors in rainbow trout juveniles: Effects on growth and fatty acid biosynthesis. Aquaculture, 509(2019)236–245.##‌ Masiha, A., Ebrahimi, E., Soofiani, N. M., Kadivar, M., 2013. Effect of dietary vegetable oils on the growth performance and fatty acid composition of fingerlings of Rainbow trout, Oncorhynchus mykiss. Food Science and Technology, 1(2), 21-29.‌ DOI:10.13189/fst.2013.010202.##Menoyo, D., Izquierdo, M. S., Robaina, L., Ginés, R., Lopez-Bote, C. J., Bautista, J. M., 2004. Adaptation of lipid metabolism, tissue composition and flesh quality in gilthead sea bream (Sparus aurata) to the replacement of dietary fish oil by linseed and soyabean oils. British Journal of Nutrition, 92(1), 41-52. DOI: 10.1079/BJN20041165.##Mohammadi, M., Imani, A., Farhangi, M., Gharaei, A., Hafezieh, M., 2020. Replacement of fishmeal with processed canola meal in diets for juvenile Nile tilapia (Oreochromis niloticus): Growth performance, mucosal innate immunity, hepatic oxidative status, liver and intestine histology. Aquaculture, 518, 734824.‌ https://doi.org/10.1016/j.aquaculture.2019.734824.##Mourente, G. and Bell, J. G. G. B., 2006. Partial replacement of dietary fish oil with blends of vegetable oils (rapeseed, linseed and palm oils) in diets for European sea bass (Dicentrarchus labrax L.) over a long term growth study: Effects on muscle and liver fatty acid composition and effectiveness of a fish oil finishing diet. Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology, 145(3-4), 389-399.‌ Doi: 10.1016/j.cbpb.2006.08.012. Epub 2006 Sep 6.##Nayak, M. Saha, A. Pradhan, A. Samanta, M. Shankar Giri, S., 2017. Dietary fish oil replacement by linseed oil: Effect on growth, nutrient utilization, tissue fatty acid composition and desaturase gene expression in silver barb (Puntius gonionotus) fingerlings. Comparative Biochemistry and Physiology, Part B 205, 1–12. DOI: 10.1016/j.cbpb.2016.11.009.##Oo, A. N., Satoh, S., Tsuchida, N., 2007. Effect of replacements of fishmeal and fish oil on growth and dioxin contents of rainbow trout. Fisheries Science, 73, 750-759.‌ DOI:10.1111/j.1444-2906.2007.01393. x.##Richard, N., Kaushik, S., Larroquet, L., Panserat, S., Corraze, G., 2006. Replacing dietary fish oil by vegetable oils has little effect on lipogenesis, lipid transport and tissue lipid uptake in rainbow trout (Oncorhynchus mykiss). British Journal of Nutrition, 96(2), 299-309. DOI: 10.1079/bjn20061821.##Tocher, D. R., 2003. Metabolism and functions of lipids and fatty acids in teleost fish. Reviews in Fisheries Science, 11(2), 107-184.‌ DOI:10.1080/713610925.##Turchini, G. M., Moretti, V. M., Hermon, K., Caprino, F., Busetto, M. L., Bellagamba, F., Francis, D. S., 2013. Monola oil versus canola oil as a fish oil replacer in rainbow trout feeds: effects on growth, fatty acid metabolism and final eating quality. Food chemistry, 141(2), 1335-1344. DOI: 10.1016/j.foodchem.2013.03.069.##Yildiz, M., Köse, I., Issa, G. & Kahraman, T., 2015. Effect of different plant oils on growth performance, fatty acid composition and flesh quality of rainbow trout (Oncorhynchus mykiss). Aquaculture Research, 46, 2885–2896. DOI:10.1111/are.12441.##Yıldız, M., Eroldoğan, T. O., Ofori-Mensah, S., Engin, K., and Baltacı, M. A., 2018. The effects of fish oil replacement by vegetable oils on growth performance and fatty acid profile of rainbow trout: Re-feeding with fish oil finishing diet improved the fatty acid composition. Aquaculture, 488, 123-133. DOI:10.1016/j. aquaculture.2017.12.030.##Webster, C.D., Lim, C., 2002. Nutrient requirements and feeding of finfish for aquaculture. CABI Publishing. New York, USA, 418 p. DOI:10.1079/9780851995199.0327.##Xie, D. Liu, X. Wang, S. You, C. Li, Y., 2018. Effects of dietary LNA/LA ratios on growth performance, fatty acid composition and expression levels of elovl5, Δ4 fad and Δ6/Δ5 fad in the marine teleost Siganus canaliculatus. Aquaculture, 484, 309–316. https://doi.org/10.1016/j.aquaculture.2017.08.039.## ##