暹罗芽孢杆菌DY3123的分离、鉴定及其降解黄曲霉毒素B1的效果研究  

Isolation,Identification of Bacillus siamensis DY3123 and Its Degradation Effect on Aflatoxin B_(1)

作　　者：倪正 张黎黎 NI Zheng;ZHANG Lili(School of Biomedical and Pharmaceutical Sciences,Hefei Institute of Technology,Hefei 230031,China;Anhui Xinlaidike Forensic Identification Center,Hefei 230012,China)

机构地区：[1]合肥理工学院生物医药学院,安徽合肥230031 [2]安徽新莱蒂克司法鉴定中心,安徽合肥230012

出　　处：《食品与生物技术学报》2024年第12期71-80,共10页Journal of Food Science and Biotechnology

基　　金：安徽省高校自然科学研究重点项目(2022AH053062);安徽省教育厅重点项目(KJ2021A0881)。

摘　　要：【目的】筛选能够降解黄曲霉毒素B(1 AFB1)的微生物菌株,并分析其降解AFB1的机理。【方法】以香豆素为唯一碳源,从松墨天牛(鞘翅目天牛科)幼虫肠道中分离、筛选对AFB1具有降解能力的菌株,同时对其降解AFB1的机理进行研究。【结果】通过初筛和复筛,成功获得一株对AFB1的降解率高达94.71%的菌株,鉴定为暹罗芽孢杆菌(Bacillus siamensis,B.siamensis)DY3123。不同细胞组分降解AFB1的试验结果表明,降解AFB1的主要活性物质来自暹罗芽孢杆菌DY3123无细胞培养基上清液;上清液降解AFB1的最适温度为80℃,最适初始pH为8.0,最适反应时间为36 h;Cu^(2+)可以提高上清液的降解活性,Zn^(2+)、Mg^(2+)和Fe^(3+)会抑制其降解活性。此外,采用3(-4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(methyl thiazolyl tetrazolium,MTT)法测定了降解产物对淋巴细胞存活率的影响,结果表明降解产物对细胞存活率无显著影响。【结论】该研究为暹罗芽孢杆菌DY3123在食品和动物饲料行业中的应用提供了参考。[Objective]This study aimed to screen out a microbial strain capable of degrading aflatoxin B1(AFB1)and decipher the degradation mechanism.[Method]With coumarin as the sole carbon source,AFB1-degrading strains were isolated and screened from the larval gut of Monochamus alternatus(Coleoptera:Cerambycidae),and the degradation mechanism for AFB1 was investigated.[Result]After primary screening and re-screening,a strain with the degradation rate reaching 94.71%for AFB1 was obtained,and this strain was identified as Bacillus siamensis(B.siamensis)DY3123.The results of experiments on the degradation of AFB1 by different cellular components indicated that the main active substances responsible for degrading AFB1 were from the cell-free culture supernatant of B.siamensis DY3123,which showed the optimum degradation performance at 80℃and pH 8.0 after 36 h.Cu^(2+)improved the degradation activity of the cell-free supernatant,while Zn^(2+),Mg^(2+),and Fe^(3+)exerted inhibitory effects.In addition,the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide(methyl thiazolyl tetrazolium,MTT)assay was employed to examine the effects of the degradation products on the viability of lymphocytes,which indicated that the degradation products had no significant impact on cell viability.[Conclusion]The findings lay a foundation for the application of B.siamensis DY3123 in the food and animal feed industry.

关 键 词：黄曲霉毒素B1 暹罗芽孢杆菌 生物降解 香豆素 筛选 

分 类 号：TS2[轻工技术与工程—食品科学与工程]