Iranian Scientific Fisheries Journal

fa مقاله علمی – پژوهشی:‌ کنترل رشد باکتری Staphylococcus aureus در فیله کپور معمولی (Cyprinus carpio) با استفاده از پد جاذب حاوی اسانس رزماری (Rosmarinus officinalis) Control of Staphylococcus aureus growth in Cyprinus carpio fillet by using absorbent pads containing rosemary essential oil بيوتكنولوژي و فرآوري هاي شيلاتي بيوتكنولوژي و فرآوري هاي شيلاتي پژوهشي Research در مطالعه حاضر تأثیر پد جاذب حاوی اسانس رزماری بر زمان ماندگاری فیله کپور معمولی تلقیح شده با باکتری Staphylococcus aureus طی نگهداری در یخچال (4 درجه سانتی‌گراد) مورد ارزیابی قرار گرفت. اسانس رزماری با استفاده از دستگاه Clevenger به روش تقطیر آبی استخراج گردید. پس از تعیین حداکثر غلظت اسانس رزماری که فاقد تاثیرات نامطلوب بر ویژگی‌‌های ارگانولپیتیک فیله ماهی بود، فیله‌‌های تلقیح شده با باکتری S. aureus CFU/g) 103) روی پد‌‌های جاذب حاوی 10 میلی‌لیتر اسانس رزماری 5/0 درصد (تیمار ۱)، 1 درصد (تیمار ۲) و 5/1 درصد (تیمار ۳) قرار گرفته و پس از بسته‌بندی در یخچال (4 درجه سانتی‌گراد) نگهداری شدند. فراسنجه‌‌های شیمیایی (pH، PV، TBA، TVB-N) و میکروبی (شمارش باکتری S. aureus، TVC و PTC) در زمان‌های 24، 72، 120، 168 و 216 ساعت اندازه‌‌گیری شدند. نتایج نشان داد که بیشترین و کمترین تعداد باکتری S.  aureus، تعداد کل باکتری‌‌های مزوفیل و باکتری‌‌های سرماگرا به‌ترتیب در تیمار شاهد و تیمار 3، هنگام نگهداری مشاهده گردید. پد جاذب حاوی 10 میلی لیتر اسانس رزماری 5/1 درصد بیشترین تأثیر را درکند شدن روند افزایشی PV، TBA و TVB-N نشان داد به‌طوری‌که در پایان زمان آزمایش مقدار این شاخص‌ها به‌ترتیب 23/0±13/ 5، 10/ ±02/ 2 و 94/1±47/ 30 در تیمار شاهد و 12/0±37/ 3، 08/0±33/ 1 و 25/1±10/ 20 در تیمار 3 مشاهده گردید. بنابراین، از نتایج این تحقیق می‌توان نتیجه‌گیری کرد که پد جاذب حاوی اسانس رزماری دارای خاصیت آنتی اکسیدانی و آنتی باکتریایی است و زمان ماندگاری فیله ماهی کپور معمولی هنگام نگهداری در یخچال را 3 روز افزایش داد. Introduction The water-holding capacity of meat stored under cold conditions gradually decreases, leading to the release of liquid from muscle tissue—a phenomenon known as exudation. The accumulation of these liquids can significantly reduce the quality of chilled meat due to microbial activity, fat oxidation, and enzymatic reactions (Dai et al., 2022). Therefore, controlling the release of exudates during storage is essential to ensure the quality and safety of fish meat. Antimicrobial absorbent pads represent a key innovation in active packaging systems (Bovi et al., 2019). These pads are designed to absorb moisture and exudates from freshly packaged foods and serve as effective carriers for antimicrobial agents. Essential oils, natural compounds with antibacterial properties, have gained popularity due to the growing consumer demand for preservative-free foods. Among these, rosemary essential oil is widely utilized in medical and pharmaceutical industries owing to its antimicrobial, anti-mutagenic, and anti-cancer properties (Luqman et al., 2021). The control of foodborne diseases is critical due to their economic implications and serious public health risks. Contaminated food, particularly fish, is often associated with illnesses caused by Staphylococcus aureus. The presence of Staphylococcus aureus in fish and its products typically results from contamination during handling, including catching, transportation, storage, processing, and preparation (Cortés-Sánchez et al., 2020). Considering these challenges, the present study aimed to evaluate the effect of absorbent pads containing rosemary essential oil on reducing the growth of Staphylococcus aureus in common carp (Cyprinus carpio) fillets. Additionally, this study investigated the chemical and microbial changes in common carp fillets during refrigerated storage. Methodology                                  Rosemary (Rosmarinus officinalis) essential oil was extracted by using the Clevenger water distillation method. To determine the maximum concentration of rosemary essential oil without adverse effects on the sensory characteristics of fish fillets, absorbent pads containing different concentrations of the rosemary essential oil (10 mL at 0.5%, 1%, and 1.5%) were prepared. The fish fillets were placed on these pads, packaged and stored in a refrigerator at 4°C for 24 h. Afterward, the fillets were cooked at 90°C for 15 minutes and evaluated by a trained sensory panel (Ojagh et al., 2010). After sensory evaluation, the fillets inoculated with Staphylococcus aureus (10³ CFU/g) were placed on absorbent pads containing 10 mL of rosemary essential oil at concentrations of 0.5% (Treatment 1), 1% (Treatment 2), and 1.5% (Treatment 3). Then the samples were packaged and stored in the refrigerator (4°C). Chemical parameters, including pH, peroxide value (PV), thiobarbituric acid (TBA), and total volatile basic nitrogen (TVB-N), as well as microbial parameters (Staphylococcus aureus, total aerobic mesophilic bacterial count [TVC] and psychrotrophic bacterial count [PTC]) were measured at intervals of 24, 72, 120, 168 and 216 h. Results The results demonstrated that Staphylococcus aureus grew well in common carp fillets, with a significant increase observed over time (p<0.05). However, the bacterial count was lower in treatments containing rosemary essential oil, showing a significant reduction with increasing rosemary essential oil concentration. This finding highlights the inhibitory effect of rosemary essential oil on Staphylococcus aureus growth across different treatments and during refrigerated storage. The highest bacterial count was observed in the control, while the lowest was recorded in Treatment 3 (10 mL of 1.5% rosemary essential oil) after 216 h of storage time (p<0.05). The total counts of mesophilic and psychrotrophic bacteria increased in all treatments with storage time and their peak was observed after 216 h of storage time (p<0.05) but the control (without essential oil) exhibited a significantly higher increase compared to the other treatments (p<0.05). Among the all treatments, the lowest bacterial count was observed in Treatment 3 (10 mL of 1.5% rosemary essential oil) at all storage times (p<0.05). The peroxide value (PV) results revealed significantly higher levels in the control compared to treatments containing rosemary essential oil. The highest PV was recorded in the control group after 216 h of storage time (p<0.05). Conversely, the lowest PV was consistently observed in Treatment 3 throughout the storage period (p<0.05). Thiobarbituric acid-(TBA) results showed that treatments containing rosemary essential oil had lower TBA levels compared to the control. Significant differences were observed between all treatments during refrigerated storage (p<0.05). This result indicated the effectiveness of rosemary essential oil in reducing lipid oxidation. Total volatile basic nitrogen (TVB-N) levels were significantly higher in the control than the treatments containing rosemary essential oil (p<0.05). TVB-N values increased in all treatments during refrigerated storage. However, higher rosemary essential oil concentrations resulted in lower TVB-N levels in treatments containing the essential oil. However, there is no significant difference in TVB-N observed between treatments 2 and 3 during refrigerated storage. No significant differences in pH were observed between all treatments after 24 h. After 72 h, a decrease in pH was noted in all treatments. Then an increase was observed in pH just to the end of the storage period. This increase was less pronounced in treatments containing rosemary essential oil, and a significant difference was observed between the control and Treatments 2 and 3 after 216 h (p<0.05). Discussion and conclusion The results of the present study demonstrate the effect of rosemary essential oil on controlling the growth of Staphylococcus aureus in common carp fillets during refrigerated storage. Rosemary essential oil contains key active compounds, including rosmarinic acid, camphor, and cineole, which contribute to its antioxidant and antibacterial properties (Borges et al., 2019). Furthermore, increasing the concentration of rosemary essential oil resulted in a reduction in Staphylococcus aureus growth in this study. Similar results have been reported by other researchers (Arbab et al., 2020). The total mesophilic and psychrotrophic bacteria count in the control and treatment 1 group were higher than treatments 2 and 3 at the end of the storage time. These results indicate an improvement in the antibacterial properties of the absorbent pads after the addition of rosemary essential oil. The results of Bakhtiari et al. (2020) showed that the addition of Carum copticum essential oil to absorbent pads controlled the growth of mesophilic bacteria in rainbow trout fillets. Reports of other researchers indicated that plant essential oils are effective in controlling peroxide values (PV). The results of the present study show that the PV of control exceeded the acceptable limit after 216 h storage time, while the PV of essential oil treatments remained within the acceptable range. A similar result was observed by Podineh et al. (2020). In this study, the lower value of TBA was obtained in the essential oil-treated groups compared to the control group. It can be attributed to the antioxidant properties of the essential oil (Becer et al., 2023). According to the present study, other studies have shown that essential oils from Origanum vulgare, Thymus mongolicus, and Illicium verum can effectively reduce TBA value. The TVB-N values in the essential oil treatments were lower compared to the control. These results are similar to the findings of other researchers (Li et al., 2024; Yang et al., 2024). The lower pH in the rosemary essential oil treatments can be attributed to the antimicrobial properties of rosemary essential oil. Finally, the results of this study demonstrate that absorbent pads containing rosemary essential oil have antioxidant and antibacterial properties and can be used to extend the shelf life of common carp fillets during refrigerated storage. Conflicts of interest The author declares that there is no conflict of interest regarding the publication of this manuscript. Acknowledgment The current study was financially supported by the University of Zabol [grant No. OZ.GR.5120]. اسانس, Staphylococcus aureus, پد جاذب, رزماری, فیله کپور معمولی Essential oil, Staphylococcus aureus, Absorbent pad, Rosemary, Cyprinus carpio fillet 39 53 http://isfj.ir/browse.php?a_code=A-10-1989-5&slc_lang=fa&sid=1 Somayeh Pishro سمیه پیشرو mrs.pishro6932@gmail.com 100319475328460039820 100319475328460039820 No گروه شیلات، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران Ebrahim Alizadeh Doughikollaee ابراهیم علیزاده دوغیکلایی ebi_alizadeh2003@yahoo.com 100319475328460039821 100319475328460039821 No گروه شیلات، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران Mohsen Shahriari Moghadam محسن شهریاری مقدم mohsen.mshahriari@gmail.com 100319475328460039822 100319475328460039822 Yes گروه محیط زیست، دانشکده منابع طبیعی، دانشگاه زابل، زابل، ایران Mostafa Yousef Elahi مصطفی یوسف الهی m.usefollahi@uoz.ac.ir 100319475328460039823 100319475328460039823 No گروه علوم دام، دانشکده کشاورزی، دانشگاه زابل، زابل، ایران