芳烃化合物对普通小球藻毒性的QSAR研究  

A DFT Study on the QSAR of Aromatic Compound Toxicity to Algae (Chlorella vulgaris)

作　　者：闫秀芬[1] 于艳春[1] 肖鹤鸣[1] 

机构地区：[1]南京理工大学化工学院,江苏南京210094

出　　处：《淮海工学院学报（自然科学版）》2006年第1期40-44,共5页Journal of Huaihai Institute of Technology:Natural Sciences Edition

基　　金：国家自然科学基金资助项目(10576068)

摘　　要：用DFT-B3LYP方法,在较高基组6-311G**水平下,全优化计算了23种苯胺、苯酚和苯甲醛衍生物。从中获得前线分子轨道能级(EHOMO,ELUMO),最正氢原子电荷Q+,最负非氢原子电荷Q-,及分子偶极矩和体积(μ,V)等描述符。结合文献中标题化合物对普通小球藻的毒性值(-logEC50)和疏水性参数(logKow),由线性回归方法成功建立QSAR模型。将-logEC50与logKow直接相关,发现标题物对普通小球藻的毒性均高于基本毒性,而多元线性回归所得二变量模型(-logEC50=-1.945+0.612logKow-7.690ELUMO,n=23,R2=0.834,F=50.322,SE=0.274,P=0.000,VIF=1.093)能更好地描述标题物对普通小球藻的毒性,由此推断,标题物取非共价作用毒性机理,其对普通小球藻的毒性作用分为两步,首先穿过细胞壁在细胞内富集,以logKow描述;其次与亲核试剂发生亲电反应,以ELUMO表示。The DFT-B3LYP method, with the basis set 6-311G^＊＊ , was employed to calculate the molecular geometries and electronic structures of 23 aromatic compounds. EHOMO, ELUMO, Q＋, Q-,μ and V were obtained from the calculated results. The acute toxicity（-log EC50） of these compounds to algae （Chlorella vulgaris） along with hydrophobicity described by log Kow, and the above six quantum chemical descriptors were used to establish the quantitative structure-activity relationships （QSARs） by multiple linear regression. Results show that the toxicity elicited by the object compounds is all greater than the basis toxicity. This toxicity is a result of electrophilic reactivity in vivo. The model established by log Kow and ELUMO was a stable one （-log EC50 =-1. 945＋0. 612log Kow-7. 690ELUMO, n=23, R^2 =0. 834, F=50. 322, SE=0. 274, P=0. 000, VIF= 1.093）. The predicted toxic values using the model are in good agreement with the experimental values. In light of the model, the toxic actions of aromatics include two steps： one is the collection of the compounds in vivo, which is described by log Kow ; the next is the electronic reactions between the chemicals and macromolecular compounds, which are represented by ELUMO.

关 键 词：芳烃 普通小球藻 毒性 密度泛函理论 QSAR 

分 类 号：X132[环境科学与工程—环境科学] O625[理学—有机化学]