对虾肠道中T-2毒素降解菌的分离纯化与鉴定

Isolation and Identification of T-2 Toxin-Degradable Strains from Shrimp Intestine

从新鲜健康的凡纳滨对虾肠道中分离筛选和鉴定降解T-2毒素微生物,为日后进一步研究T-2毒素(T-2)降解菌株的相关特性及其分布规律提供参考。取新鲜健康的凡纳滨对虾肠道,通过对该肠道菌群进行定性定量分析;从T-2与对虾肠道共培养液分离纯化得到6株优势菌株;将6株优势菌株分别和T-2在胰蛋白胨大豆(TSB)肉汤中进行共培养,采用LC-MS/MS法检测该培养液前后T-2含量,筛选得到T-2降解菌株,并用微生物鉴定仪VITEK2和16S rRNA鉴定目标菌株。TSB肉汤中检测T-2的标准曲线线性良好(R=0.999 5),T-2加标回收率为91.5%~108.4%,检测限为0.01 ng/m L,相对标准偏差为0.0%~8.4%和精密度为94.5%~107%。对虾肠道中的蜡状芽胞杆菌(Bacillus cereus)和阴沟肠杆菌(Enterobacter cloacae)对T-2毒素降解率最高,分别达到91.8%和78.8%。

T-2 toxin（T-2） degradable microbes was to isolate and screen from fresh and healthy intestine of white prawn（Litopenaneus vannamei）,to provide theoretical foundation for further study on its related features and distribution law of T-2 toxin-degradable strains. Intestine of fresh healthy white prawn（L. vannamei） was taken,the intestinal microbial population was analyzed qualitatively and quantitatively： six ascendant strains were obtained by co-cultured in T-2 with the shrimp intestinal tract cultural liquid,the six ascendant strains were co-cultured in tryptone soy broth（TSB） with T-2 respectively; then adopted LC-MS/MS method to detect T-2 content before and after cultivation,and screened obtained the T-2 degradable strains. And identified the targeted strains with VITEK2 microorganism identification instrument,and characterized by 16 s rRNA sequencing. The results showed that the standard curve of T-2 had a good linear（R = 0. 999 5） detected in TSB broth. Its fortified recoveries were at 91. 5% - 108. 4%,limited detection was 0. 01 ng/m L,the relative standard deviation was 0. 0% - 8. 4% and the accuracy was 94. 5% -107%. Bacillus and Enterobacter cloacae in the shrimp intestine were the highest to degrade T-2,and reached up to91. 8% and 78. 8%,respectively.