QSAR模型预测石化废水中芳香族物质对厌氧菌群的综合毒性

QSAR Modelling for Predicting Comprehensive Toxicity of Aromatic Substances to Anaerobic Microflora in Petrochemical Wastewater

厌氧消化可有效降解芳香化合物,但其浓度对厌氧微生物活性影响显著,从而引起出水水质的波动。为预测芳香化合物对厌氧微生物的毒性作用,采用厌氧微生物毒理试验,以芳香化合物48 h半数效应浓度(48 h-EC_(50))值为样本,基于理化和量子化学结构描述符,利用多元逐步线性回归(multiple stepwise linear regression,MSLR)建立了芳香化合物对厌氧微生物抑制效应的定量构效关系(quantitative structure activity relationship,QSAR)模型。结果表明,芳香化合物对厌氧微生物的毒性影响与正辛醇/水分配系数(log K_(ow))、摩尔折射率(MR)以及分子偶极矩(μ)有关,确定系数(R^(2))为0.928,三者对模型的贡献程度分别为51.30%、27.63%和21.07%。芳香化合物毒性与log K_(ow)和MR相关性显著(r^(2)分别为0.8105和0.7128)。

The comprehensive toxicity of aromatic compounds during the anaerobic digestion of petrochemical wastewater was investigated by quantitative structure activity relationship(QSAR).The aromatic compounds from petrochemical wastewater stream were regarded to be significantly degraded through the active anaerobic microorganisms,though its high concentration caused the effect fluctuation of anaerobic digestion process on water quality of effluent.To understand the aromatic compound toxicity to anaerobic microorganisms,the toxicological method of anaerobic microorganisms was conducted by sampling 48 h median effect concentration(48 h-EC_(50))of aromatic compounds.Based on physicochemical and quantum chemical structure descriptors,the QSAR model about aromatic compounds was carried out by the multiple stepwise linear regression(MSLR).The inhibitions of aromatic compounds on the anaerobic microorganisms were predicted by the model with relating the parameters of the octanol water partition coefficient(log K_(ow)),the molar refractive index(MR)and the molecular dipole moment(μ).The results showed that R^(2)(coefficient of determination)was 0.928 and contributions of model parameters were 51.30%,27.63%and 21.07%respectively.According to the acceptable criteria,the model indicated with high goodness-of-t and robustness.Besides,the toxicity of aromatic compounds was correlated with log K_(ow)and MR significantly(r^(2)was 0.8105 and 0.7128 respectively).