中文摘要：黄曲霉是感染作物并产生最强致癌作用及毒性的黄曲霉毒素的主要霉菌。先前的研究表明，一种海洋细菌，巨大芽孢杆菌，能抑制花生中黄曲霉生长及黄曲霉毒素合成。本研究采用LC-MS/MS，从巨大芽孢杆菌发酵液中，鉴定出五种在三个离子峰中具有不同结构的肽，并证明了它们具有抗黄曲霉活性。根据肽产生的结构信息，合成了多个衍生肽（构成及构型差异），并检查了它们抑制黄曲霉生长、孢子萌发及黄曲霉毒素产生的功效。结果表明三种肽，L-Asp-L-Orn (D1O)、L-Asp-L-Asn (D1N)和L-Asp-L-Asp-L-Asn (D2N)能显著抑制黄曲霉生长。共焦显微镜研究发现D1O、D1N和D2N能自发进入黄曲霉菌丝。同时，定量RT-PCR（qRT-PCR）、黄曲霉毒素产生和孢子萌发试验证明，三种肽进入黄曲霉细胞后，它们抑制了分生孢子及黄曲霉毒素产生，但不抑制菌丝营养生长和孢子萌发。
外文摘要：Aspergillus flavus is one of the major moulds that infect crops, and produces the most carcinogenic and toxic compounds-aflatoxins. The previous research demonstrated that a marine bacterium, Bacillus megaterium, inhibited the growth of A. flavus and the biosynthesis of aflatoxin B1 in peanuts. In this study, five characterized peptides with distinct structures in three ion peaks were identified by LC-MS/MS and demonstrated to have anti-A. flavus activities from B. megaterium fermentation broth. Based on the structural information generated from the peptides, several derivatives (different composition and configuration) were synthesized and examined their efficacy in terms of inhibiting growth of A. flavus, spore germination, and aflatoxin production. Results showed three peptides L-Asp-L-Orn (D1O), L-Asp-L-Asn (D1N) and L-Asp-L-Asp-L-Asn (D2N) could significantly inhibit the growth of A. flavus. The results of confocal microscopy showed that D1O, D1N and D2N can spontaneously enter into the hyphae of A. flavus. Meanwhile, data of quantitative RT-PCR (qRT-PCR), aflatoxin production and spore germination assay demonstrated that after three peptides entered into the cells of A. flavus, they inhibited conidiation and aflatoxin production, but didn't inhibit hyphae vegetative growth and spore germination.
外文关键词：Aspergillus flavus；Aflatoxin；Bacillus megaterium；Inhibition；Biocontrol
作者：Chen, YJ；Kong, Q；Liang, Y
作者单位：Ocean Univ China
期刊名称：FOOD CONTROL
期刊影响因子：3.388
出版年份：2019
出版刊次：1
点击下载：新发现的三种巨大芽孢杆菌肽能强烈抑制黄曲霉生长及黄曲霉毒素产生