二苯甲酮类紫外防晒剂发光菌急性毒性及QSAR研究

Acute Toxicity and QSAR Studies on Benzophenone-type UV-filters to Photobacterium

二苯甲酮类化合物广泛用于防晒剂、塑料添加剂、香味剂等。随着紫外防晒产品的大量使用,其环境及健康风险越来越受到人们的关注。为揭示二苯甲酮类污染物的毒性特征,选择了14种二苯甲酮类化合物作为目标化合物,测试了它们对发光细菌的急性毒性效应。分别运用二维、三维定量构效相关技术和分子对接技术探讨了目标化合物的分子结构特征对毒性效应的影响。结果表明14种二苯甲酮类化合物对发光菌急性毒性的EC50值在17.67到243.82 mg·L-1范围内,其中2-羟基-4-甲氧基-5-磺酸基二苯甲酮的急性毒性最低,2,2',4,4'-四羟基二苯甲酮的毒性最高。羟基取代的二苯甲酮化合物的急性毒性随着分子中羟基数量的增加而升高;具有相同羟基数量的二苯甲酮类化合物,羟基位于苯环4-位时毒性最高,3-位时次之,2-位时毒性最低。QSAR结果表明,运用静电场、氢键受体场和氢键供体场能很好解释这类化合物的毒性特征,若在苯环4-位引入带正电荷的官能团、在苯环2-,4-位引入氢键受体,都将导致毒性升高。上述研究结果将为科学评价该类化合物的潜在生态风险提供基础数据。

Benzophenones （BPs） are widely used in UV filters, plastic additives, and fragrance enhancers. With the wide use of UV filters products, their potential risk to the ecological and human health has been concemed greatly. Fourteen BPs were selected as targets, and their acute toxicity was tested using the photobacterium assay. The related substituent contribution was disclosed by using 2- and 3-dimension quantitative structure-activity relationship （QSAR） and molecular docking methods. The results revealed that the EC50 values of 14 BPs ranged from 17.67 to 243.82 mg· L^-1, and the acute toxicity of 2-hydroxy-4-methoxy-5-sulfonic acid BP was the lowest, while that of 2,2＇ ,4,4＇ -tetrahydroxy-BP was the highest. The acute toxicity increased with the increasing number of hydroxy group in BPs. For the BPs containing same number of hydroxy groups, BPs with hydroxy group at 4-position of benzene ring exhibited the highest toxicity, and lower toxicity was observed with hydroxy group at 3-position, while that at 2-position showed the lowest toxicity. Furthermore, 2- and 3- dimensional quantitative structure - activity relationships （2D- and 3D - QSAR） studies indicated that hydrogen-bond interactions and electrostatic effects were determinants for the acute toxicity of the BPs. The introduction of groups with positive charges at 4-position, or hydrogen-bond acceptor at 2-, 4-position of benzene ring, would lead to the increase of acute toxicity. The pres- ent results would provide useful information for evaluating the potential ecological and human health risk of BP- type UV-filters.