Study About Beauvericin and Enniatins: Method Validation and Survey for Foods in Japan

Beauvericin (BEA) and enniatins (ENNs) are cyclic depsipeptide mycotoxins mainly produced by Fusarium species. To investigate their presence in retail foods in Japan, we developed an analytical method for the simultaneous determination of BEA, enniatin A (ENNA), enniatin A₁ (ENNA₁), enniatin B (ENNB), and enniatin B₁ (ENNB₁). Five mycotoxins were extracted from food samples using a mixture of acetonitrile and water, and then purified using a C18 cartridge. LC-MS/MS was used to quantify the purified mycotoxins. This method was validated in an inter-laboratory study. Eight laboratories participated in the study, and three spiked and two naturally contaminated wheat samples were analyzed. The ranges of the mean recoveries of BEA, ENNA, ENNA₁, ENNB, and ENNB₁ were 92‒94, 94‒96, 97‒98, 98‒99, and 98‒100%, respectively. The relative standard deviations for repeatability and reproducibility in spiked and naturally contaminated samples ranged from 2.1 to 5.7% and from 6.2 to 15.3%, respectively. After the application of the method to the analysis of these five mycotoxins in other foods was confirmed by recovery tests, 658 food samples including cereals, bean products and dry fruits were analyzed using the developed analytical method. BEA, ENNA, ENNA₁, ENNB, and ENNB₁ were detected in 23%, 7%, 17%, 40% and 33% of all samples, respectively, at >1.5 µg/kg. About the result of BEA, the highest mean level in 12 food groups was shown in soybean flour samples (13 µg/kg). Among the four ENNs, the positive rate of ENNB was the highest in all food groups. ENNB was mainly detected in rye flour and wheat flour, and the mean ENNB levels of rye flour and wheat flour were 987 and 49 µg/kg, respectively. Our results are useful for the risk assessment of BEA and ENNs in retail foods in Japan.