利用甲基对硫磷降解菌DLL-E4消除农产品表面农药污染的研究

利用甲基对硫磷降解菌DLL-E4(Pseudomonas sp.)能高效分解甲基对硫磷的特性，研究了消除农产品表面农药残留污染的途径，采用菌体发酵液、发酵液上清液、菌体蛋白、粗酶液、添加菌体蛋白的洗涤剂以及洗涤剂，处理了小青菜、茶叶、黄瓜表面的农药残留污染。结果表明，使用发酵液和不同的酶制剂可以有效去除这些产品表面的农药残留污染，最高去除率可达100％；DLL-E4上清液中有一些酶促反应促进因子，有助于酶更好地发挥作用，洗涤剂和酶直接混合作用，有助于消除茶叶表面的农药残留，但对于黄瓜和小青菜则相反。在所有选用的模式中，使用粗酶液和菌体蛋白效果最好，对黄瓜、小青菜和茶叶合适的酶制剂浓度分别为2％、5％和10％，粗酶液同时还能降解甲胺磷、辛硫磷、毒死蜱等农药。

Use of methyl parathion (MP)-degrading strain DLL-E4(Pseudomonas sp) to remove MP residue on the surface of agricultural products

In this paper, derivations from DLL-E4, including fermented liquid, its centrifuged (3000 x g, 10 min) supernatant, pellet extract with supersonic, crude enzyme(supernatant and pellet extract), detergent, and mixture of detergent and pellet extract, were used to degrade the MP residue on the surface of Chinese cabbage, tea and cucumber. The results showed that all of them were effective, with the best effect of 100%. Some constituents in the supernatant of fermented liquid could stimulate the enzymatic activity. For tea, the mixture of detergent and enzyme was more effective, but the opposite was found for the other two crops. In all treatments, crude enzyme and pellet extract had the best effect, and the rational added amount of enzyme was 2%, 5% and 10% for cucumber, Chinese cabbage and tea, respectively. Crude enzyme also could degrade methamidophos phoxim and chlorpyrifos.