Discrete and combined effects of Ylang-Ylang (Cananga odorata) essential oil and gamma irradiation on growth and mycotoxins production by Fusarium graminearum in maize

Abstract

In the present study, discrete and combined inhibitory effects of Cananga odorata essential oil (COEO) and irradiation were established on growth and production of deoxynivalenol (DON) and zearalenone (ZEA) by Fusarium graminearum in maize kernels. Chemical profile of COEO was characterized by GC-MS and a total of 35 chemical constituents were identified, and major compounds were linalool (29.15%), germacrene-D (11.82%), and thymol (8.45%). The COEO and irradiation have inhibited the fungal growth and mycotoxins at 3.9 mg/g and 7.5 kGy, respectively. Distinct inhibitory activity of COEO and irradiation on fungal growth and mycotoxins was assessed by constructing linear regression curves. Regression models of COEO and irradiation have presented good coefficients of determination (R2) of 0.9886 and 0.9798 for fungal growth (log CFU), 0.97 and 0.9622 for DON, and 0.9811 and 0.9807 for ZEA, respectively. The linear regression models concluded that COEO and irradiation have dose-dependent inhibitory effect on fungal growth and mycotoxins. Further, combined inhibitory effect of COEO and irradiation on fungal growth and mycotoxins was assessed by checkerboard method. The combined treatment of COEO and irradiation was too shown decent coefficients of determination (R2) and found greatly effective. The combined treatments of COEO and irradiation have inhibited the fungal growth and mycotoxins in stored maize kernels much below than their discrete inhibitory levels, and it was noticed at 2.5 mg/g of COEO and 4 kGy of irradiation. The study concluded that combination of essential oil and irradiation could be highly efficient decontamination technique to diminish the fungal growth and mycotoxins in agricultural commodities.