Document Type : Research Paper
Authors
1
Department of Fisheries, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.
2
Assistant Professor, Department of Fisheries, Faculty of Agriculture and Natural Resources, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.
3
Associate Professor, Department of Fisheries, Faculty of Agriculture and Natural Resources, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.
Abstract
In this study, the antibacterial effects of Mentha piperita (0, 0.4 and 0.8%) and nisin (0, 0.25 and 0.75 µg/ml) alone and together for control of Streptococcus iniae in rainbow trout (Oncorhynchus mykiss) fillets were evaluated at 4 and 8°C. The results showed that M. piperita essential oil had a higher inhibitory effect in both temperatures of 4 and 8°C compared to nisin. At 4°C, the essential oil of M. piperita and nisin in comparison to the control treatment had a better effect and in combined treatment, 0.75 μg/ml nisin and 0.8% M. piperita essential oil, growth of Streptococcus iniae from day third stopped. Antimicrobial activity was also increased by increasing the amount of nicine and M. piperita essential oil and at 8 °C, this combination was able to prevent bacterial growth until the ninth day. The results of this study showed that M. piperita essential oil had more antibacterial activity compared to nisin against S. iniae. In both treatments, with increasing levels of nisin and M. piperita essential oil, the inhibitory activity increased at a temperature of 4 and 8 °C in comparison with control and treatments with lower amounts of nisin and M. piperita essential oil. At both storage temperatures, the best performance was observed in treatment with the highest level of 0.75 μg/ml nisin and 0.8% M. piperita essential oil.
Keywords
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