鼠李糖脂对17α-炔雌醇生物降解过程的强化作用

Biodegradation Mode of 17α-ethinylestradiol Affected by Rhamnolipidic Biosurfactant

采用好氧生物降解实验,考察了鼠李糖脂对底泥/河水混合体系中17α-炔雌醇(EE2)的生物降解特性的影响。结果表明,随体系中鼠李糖脂浓度的增加,EE2的可生物降解性明显呈大幅度地提高。HPLC-PDA扫描检测结果表明,EE2降解过程中主要产生极性和生物可降解性差异均较大的3种代谢中间产物。外加葡萄糖投加量足够时,外加碳源可以转变成为微生物降解有机物的共代谢基质。鼠李糖脂影响及作用下,微生物摄取吸收有机物的模式可以有多种。鼠李糖脂作为外源添加物,其共代谢效应有可能促使有机物增溶胶束直接被微生物菌体利用。

The biodegradation of 17α-ethinylestradiol （EE2） in the sediment/water system affected by rhamnolipids was studied. With the increase of the rhamnolipid concentration, EE2 biodegradability was improved greatly. In the process of EE2 biodegradation, mainly three kinds of metabolic intermediates with great differences both in polarity and biodegradability were produced. When the dosage of glucose carbon resource was larger, the carbon resource became cometaboUsm suhstrate of EE2 degradation. There were multiple modes for microbial cell uptake of EE2. Cometabolism of rhamnolipid was likely to increase the efficacy of microbial direct uptake for the EE2 solubilizated micelles.