The purpose of this study was to evaluate the inhibitory effect of allyl-isothiocyanate (AITC) and benzyl-isothiocyanate (BITC) on fungal growth and Ochratoxin A (OTA) production by Aspergillus ochraceus, A. carbonarius and A. niger. Here, we found that spore germination and fungal growth of the three fungi were significantly inhibited when the concentration of AITC and BITC was higher than 1.25 μg/mL. The inhibitory effect of AITC or BITC on A. carbonaceus and A. ochraceus was significantly stronger than that of A. niger. Scanning electron microscopy showed that the mycelia of all three fungi were changed by AITC and BITC. Compared with A. ochraceus and A. carbonarius, the damage to A. niger was lower. For OTA production, AITC and BITC could significantly down-regulated the expression of all five OTA biosynthesis genes in A. niger and A. carbonarius. In A. ochraceus, although several OTA biosynthesis genes were up-regulated, the key PKS gene was down-regulated by AITC and BITC. Twenty-five μg/mL of AITC or BITC could reduce the infection of the three fungi on grapes with inhibition rates of 28%–36% during 14 days and prolong the shelf life of grapes. In maize, the OTA production of the three fungi was significantly reduced by 25 μg/mL of AITC and BITC with the inhibition rates 68.04%–93.49% and 65.87%–75.45%, respectively. These results suggest that AITC and BITC can be used as natural fungicides to prevent A. niger, A. carbonarius and A. ochraceus from infecting grapes and maize and control OTA contamination.

本研究的目的是评价烯丙基异硫氰酸酯（AITC）和苄基-异硫氰酸酯（BITC）对真菌生长和赭曲霉毒素A（OTA）所生产的抑制作用赭曲霉，炭黑曲霉和黑曲霉。在这里，我们发现当 AITC 和 BITC 的浓度高于 1.25 μg/mL 时，三种真菌的孢子萌发和真菌生长受到显着抑制。AITC或BITC对A. carbonaceus和A. ochraceus的抑制作用明显强于A. niger。扫描电镜显示，AITC 和 BITC 均改变了三种真菌的菌丝体。与A. ochraceus和A. carbonarius，对A. niger的伤害较低。对于 OTA 生产，AITC 和 BITC 可以显着下调A. niger和A. carbonarius中所有五个 OTA 生物合成基因的表达。在A. ochraceus 中，虽然几个 OTA 生物合成基因被上调，但关键的PKS基因被 AITC 和 BITC 下调。25 μg/mL的AITC或BITC可以减少三种真菌对葡萄的感染，14天抑制率为28%~36%，延长葡萄的货架期。在玉米中，25 μg/mL AITC 和 BITC 显着降低了三种真菌的 OTA 产量，抑制率分别为 68.04%–93.49% 和 65.87%–75.45%。这些结果表明，AITC和BITC可作为天然杀菌剂，防止黑曲霉、炭黑曲霉和赭曲霉感染葡萄和玉米，控制OTA污染。