The Antifungal Effect Of Compound Antifungal Agent On High Moisture Corn

Corn is one of the three major crops in China.It can be contaminated by molds in the field,or during storage,and are prone to mildew especially under high moisture.Cereals contaminated with aflatoxins are not only harmful to animal and human health,but also cause economic losses.Although the chemical antifungal agents can reduce the loss of mildew,the problems of secondary pollution and drug resistance are also prominent.The aim of this study was to find a synergistic antifungal compound against A.flavus and demonstrate the antifungal effects of composite essential oils（CEO）on high-moisture corn.Furthermore,the CEO was combined with inert carrier to obtain an eco-friendly anti-fungal agent along with high efficiency.The main results are as follows:1.Through direct contact and vapor phase,three kinds of essential oils,cinnamon,oregano and lemongrass EOs,were selected from 11 kinds of plant essential oils.2.And the three EOs had a synergistic effect when combined at a volume ratio of 1:5:48,as indicated by FICI values.3.CEO showed remarkable inhibitory activity against A.flavus on both mycelial growth and aflatoxin production.4.Down-regulation of afl T,afl R,afl D,afl P,afl M and afl S genes in the aflatoxin synthesispathway upon CEO treatment contributed to lower aflatoxin production.5.Aldehydes and alcohols were identified by FTIR and GC-MS as the main componentsin CEO.CEO mainly consisted of（Z）-citral（33.34%）,（E）-citral（32.88%）and o-cymen-5-ol（19.84%）,followed by limonene（4.29%）and cinnamaldehyde（3.76%）.6.CEO had good antifungal effect on corn with a moisture content 12%and 15%,respectively,but has a poor antifungal effect on corn with a water content of 18%.7.Inert carriers improved the inhibition ability of the CEO to A.flavus in high moisture corn.Among them,Diatomite,Attapulgite and H-Si O₂ didn’t promote the growth of A.flavus significantly,and had a good embedding effect on CEO.8.The three carriers are compounded according to Diatomite:Attapulgite:H-Si O₂=7:4:3（m:m:m）to obtain a compound carrier.The compound carrier:CEO=1:1（m:m）is used to obtain a compound antifungal agent,which can be applied to the antifungal storage of high-moisture corn to prevent corn mildew.The compound antifungal agent obtained in this research can not only inhibit the mildew of high moisture corn in a short period of time,but also can be used as an antifungal agent for long-term storage of corn.