中文摘要：由镰刀菌产生的多种单端孢霉烯族真菌毒素污染农产品是一个食品安全问题，严重影响了全球的粮食生产和销售。重要的是，暴露于多种单端孢霉烯可能会增加对动物的毒性，因为它们具有协同作用和/或叠加效应。为了解决这个问题，本研究旨在实现一种新的生物学特性，能够在需氧和厌氧条件以及较宽的温度范围内净化污染食物和饲料的多种单端孢霉烯族真菌毒素。本研究报道了获得有效、稳定的微生物菌群DX100的富集过程，该菌群能够使几种污染食品的单端孢霉烯族真菌毒素脱环氧化。DX100，在广泛条件下具有脱环氧化的能力，代表着具有巨大工业潜力的独特酶源，它可以减少多种单端孢霉烯族毒素对食物/饲料的污染，并最大限度地减少毒素协同/叠加细胞毒性对消费者健康的影响。
外文摘要：Background Contamination of agricultural commodities with multiple trichothecene mycotoxins, produced by toxigenic Fusarium species, is a food safety issue, which greatly affects grain production and marketing worldwide. Importantly, exposure to multiple trichothecenes may increase toxicity in animals due to their synergistic and/or additive effects. To address the problem this study aimed to achieve a novel biological trait capable of detoxifying various food and feed contaminating trichothecenes under aerobic and anaerobic conditions and wide range of temperatures. Results A highly enriched microbial consortium (called DX100) capable of transforming eleven trichothecenes to significantly less toxic de-epoxy forms was achieved after prolonged incubation of soil microbial culture with 200 μg/mL deoxynivalenol (DON). DX100 demonstrated de-epoxidation activity under aerobic and anaerobic conditions, a greater range of temperatures and around neutral pH. The consortium contains 70% known and 30% unknown bacterial species, dominated by Stenotrophomonas species. Probably novel bacteria including strains of Stenotrophomonas and Alkaliphilus-Blautia species complex could be involved in aerobic and anaerobic de-epoxidation of trichothecenes, respectively. DX100 showed rapid and stable activity by de-epoxidizing 100% of 50 μg/mL deoxynivalenol at 48 h of incubation and retaining de-epoxidation ability after 100 subcultures in mineral salts broth (MSB). It was able to de-epoxidize high concentration of DON (500 μg/mL), and transformed ten more food contaminating trichothecenes into de-epoxy forms and/or other known/unknown compounds. Microbial de-epoxidation rate increased with increasing trichothecene concentrations in the broth media, suggesting that DX100 maintains a robust trichothecene detoxifying mechanism. Furthermore, the nature of microbial de-epoxidation reaction and inhibition of the reaction by sodium azide and the finding that bacterial cell culture lysate retained activity suggests that certain cytoplasmic reductases may be responsible for the de-epoxidation activity. Conclusions This study reports the enrichment procedure for obtaining an effective and stable microbial consortium DX100 capable of de-epoxidizing several food contaminating trichothecene mycotoxins. DX100, which has de-epoxidation ability under wide range of conditions, represents a unique enzymatic source which has great industrial potential for reducing contamination of foods/feeds with multiple trichothecenes, and minimizing their synergistic/additive cytotoxic effects on consumer health.
外文关键词：Biodetoxification；Food contamination；Fusarium mycotoxins；Microbial de-epoxidation；Trichothecenes
作者：Ahad, R；Zhou, T；Lepp, D；Pauls, KP
作者单位：Agr & Agri Food Canada
期刊名称：BMC BIOTECHNOLOGY
期刊影响因子：2.452
出版年份：2017
出版刊次：3
点击下载：11种污染食物和饲料的单端孢霉烯族真菌毒素的微生物脱毒