Synergistic effects of the Nisin andCuminum cyminumessential oil and pH on the thermostable direct hemolysin toxin production of theVibrio parahaemolyticus

Abstract

The investigation was done to study the effects of pH, Nisin and C. cyminum essential oil on the titer of TDH toxin produced by V. parahaemolyticus. Chemical components of C. cyminum were analyzed using the GC-mass. V. parahaemolyticus strains were inoculated onto the BHI media (with different pH levels of 5, 6, and 7) contained different concentrations of Nisin and C. cyminum essential oil. Titers of TDH toxin were assessed. Benzaldehyde (27.18%) and phenyl propoanol (17.50%) were the most commonly detected components. Increase in the pH caused increase in the titer of TDH. C. cyminum and Nisin had higher antibacterial effects on lower pH. The pH = 5 caused reduction in the titer of TDH at concentrations of 0.005% and 0.015% of C. cyminum. Using C. cyminum essential oil and Nisin in low pH caused decrease in the titer of TDH toxin produced by V. parahaemolyticus. Practical applications Using medicinal plants like C. cyminum is a practical approach to reduce the ability of V. parahaemolyticus to the production of TDH toxin. GC-mass analysis of C. cyminum showed high contents of antimicrobial and antioxidant components. The result showed that the Cuminum cyminum and Nisin had better antimicrobial effects against TDH toxin of V. parahaemolyticus on lower levels of pH. The application of the results may be beneficial for using C. cyminum and Nisin in lower pH levels, especially in foods with the risk of V. parahaemolyticus TDH toxin production.