单歧藻对烷基酚类化合物的生物降解性研究

以4-乙基酚为研究对象,研究其在单歧藻作用下的可降解性及其影响因素,然后对邻甲酚,间甲酚,4-辛基酚的生物降解动力学进行了比较,最后运用生物降解数据logK对8种烷基酚类化合物进行了结构-生物降解性(QSBR)的研究。研究结果表明:单歧藻对烷基酚类化合物的降解速率与藻细胞浓度和有机物初始浓度有关,化合物的降解动力学常数K值由污染物的初始浓度所决定,化合物的疏水性参数logKOW、分子量MW、一级价键连接指数1XV、二级价键连接指数2XV、生成热ΔHf和分子偶极距μ能够较好地拟合烷基酚类化合物的生物降解速率,其中2XV拟合效果最好。并在此基础上,初步分析了烷基酚类化合物的生物降解机理,认为空间参数是决定其生物降解的主要因素,化合物的生成热和电性参数μ、Ehomo的影响也不可忽视。

Kinetics of Alkyl Phenols Bioaccumulation and Biodegradation by Tolypothrix

With different Tolypothrix density and 4-ethylphenol concentration, tests were conducted to study the biodegradability of 4-ethylphenol and its influencing factors. The biodegradation of alkyl phenol by Tolypothrix was studied and compared. QSBR study was made for biodegradation of 8 kinds of alkyl phenols by Tolypothrix. Results indicated that Tolypothrix was able to degrade 4-ethylphenol and the degradation rate depended on Tolypothrix density and initial 4-ethylphenol concentration. Preliminary analysis of alkyl phenol biodegradation mechanism holds that steric parameters were dominant factors governing the biodegradability of alkyl phenols with the best simulating effect and electronic parameter on the final biodegradation products not being ignored.