取代苯甲酸在天然河流中的生物降解及其定量结构--生物降解性相关研究

以天然河流水作为微生物源 ,采用碘量法测定了 2 0种苯甲酸类化合物的 5日生化需氧量 ,并以其占理论需氧量的百分数作为表征生物降解性的参数 ,得出各类取代苯甲酸类化合物的生物降解能力为 :羟基 >氨基 >羧基 >甲氧基 >氯基 >硝基 ;对于同一种取代基 ,对位取代基化合物生物降解能力最大 ,而邻位、间位取代基化合物生物降解能力大体相同。计算了苯甲酸类化合物的分子连接性指数 ,并以 5日生化需氧量占理论需氧量的百分数为参数建立了 QSBR模型。分析结果表明 ,分子连接性指数5Xvpc、5Xp- 5Xvp 能较好地反映取代苯甲酸的生物降解性

Biodegradation and QSBR Study of Substituted Benzoic Acids in Natural River

Taking the water from natural river as the source of bacteria,Biochemical Oxygen Demands of 20 substituted benzoic acids in five days were measured by iodinmetry method.The ratio of the existed Oxygen Demand to the theoretical Oxygen Demand was accepted as a parameter of biodegradability.The biodegradability for each kind of substituted benzoic acids was as follows:nitro>chloro>methoxyl>carboxyl>amino>hydroxyl.As for the same kind of substitutent,the biodegradability of metra substituted benzoic acids was better than the orth and para substitutent.Molecular connectivity indexes were calculated which were used as a parameter to develop the QSBR model with the parameter of the ratio of the existed Oxygen Demand to the theoretical Oxygen Demand.It has shown the molecular connectivity indexes 5X v pc and 5X p- 5X v p could be better to reflect the biodegradability of substituted benzoic acids.