对虾肠道中T-2毒素降解菌的分离纯化与鉴定

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%。

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

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 16s 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/mL, 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 to 91.8% and 78.8%, respectively.