为探明T-2毒素持续染毒后的对虾肌肉中mT-2s的残留规律，及其对对虾的脂溶性成分含量的影响。采用20 d蓄积染毒法获得不同染毒剂量组（0、0.5、1.2、2.4、4.8、12.2 mg/kg饲料）的对虾肌肉组织，采用LC-MS/MS检测经三氟乙酸（TFA）水解处理前后样本中的T-2毒素含量，以T-2增量表示mT-2s含量。同时采用索氏提取法测粗脂肪，HPLC法测VA、VD3和VE含量。结果表明，对虾肌肉经TFA水解处理前未发现游离态T-2毒素，水解后检出T-2毒素，即mT-2s，且其含量与染毒剂量呈正相关。而染毒剂量对不同脂溶性成分含量的影响表现出较大差异。高剂量染毒时，粗脂肪、VA和VD3含量呈显著下降（p＜0.05），而VE的含量呈波动性变化。低剂量染毒时，粗脂肪、VD3和VE含量显著升高（P＜0.05），表现出低剂量刺激效应，但是粗脂肪与VA含量与mT-2s呈负相关，可能二者与mT-2s的存在形式有关，此结论为挖掘mT-2s的预警指标提供参考。

This study explored the content of masked T-2 toxin (mT-2) residues and the effect of this toxin on fat-soluble components in T-2 toxin-exposed muscle tissues of shrimp (Litopenaeus vannamei). L. vannamei muscle tissues from the groups treated with different doses of T-2 toxin (0, 0.5, 1.2, 2.4, 4.8, and 12.2 mg/kg feed) after 20 days of cumulative exposure. Content of the T-2 toxin in the muscle tissues before and after trifluoroacetic acid (TFA) hydrolysis was determined by performing liquid chromatography–tandem mass spectrometry; content of mT-2 was expressed by the increment of T-2 toxin. Crude fat content was determined by using Soxhlet method, and vitamin A (VA), vitamin D3 (VD3), and vitamin E (VE) content was determined by performing high-performance liquid chromatography. Free T-2 toxin was not detected in shrimp muscle tissues before TFA hydrolysis but was detected after TFA hydrolysis. Moreover, its content was positively correlated with the dose of T-2 toxin administered. Different doses of the T-2 toxin exerted significantly different effects on the content of fat-soluble components. Treatment of shrimps with a high dose of the T-2 toxin significantly decreased crude fat, VA, and VD3 content (p< 0.05) but fluctuated VE content. Treatment of shrimps with a low dose of the T-2 toxin significantly increased crude fat, VD3, and VE content (p < 0.05), indicating a low-dose stimulatory effect. Crude fat content was negatively correlated and VA and mT-2 toxin content was positively correlated with the existing form of the T-2 toxin. These results can be used as a reference to determine the indicators of mT-2 toxicity.

国家自然科学基金资助项目(31171634，31371777，31201309)