中文摘要：

研究了二氯甲烷和1,2-二氯乙烷对蛋白核小球藻（Chlorella pyrenoidosa）生长和生化指标的毒性效应.结果表明,二氯甲烷和1,2-二氯乙烷对蛋白核小球藻生长有影响.随着2种毒物浓度的增大,其对藻生长的抑制越明显,藻细胞密度均呈现下降的趋势.二氯甲烷和1,2-二氯乙烷抑制蛋白核小球藻生长的96h-EC50分别为550.1mg/L和276.0mg/L,1,2-二氯乙烷的毒性要稍强于二氯甲烷.2种毒物联合作用时基本表现为拮抗作用.叶绿素a含量随毒物浓度增加而迅速下降,SOD和CAT的活性随毒物浓度升高呈现先升高后下降的＂钟形曲线＂.MDA的含量随毒物浓度升高而急剧上升,膜脂过氧化加剧.表明毒物通过产生活性氧自由基引起生物大分子的氧化损伤可能是其对蛋白核小球藻产生毒性效应的主要原因.

英文摘要：

The acute toxic and biochemical effects of dichloromethane and 1,2-dichloroethane to Chlorella pyrenoidosa were assessed.The experimental results showed that dichloromethane and 1,2-dichloroethane had some inhibition to growth of the algae.With increasing concentration of the organic toxicant,the cell density decreased.The 96 h-EC50 of dichloromethane to Chlorella pyrenoidosa was 550.1 mg /L;the 96 h-EC50 of 1,2-dichloroethane to Chlorella pyrenoidosa was 276.0 mg /L,toxicity of 1,2-dichloroethane is a little stronger than that of dichloromethane;the joint toxicity of two organic toxicants was showed as antagonism.Content of chlorophyll a,activities of superoxide dismutase（SOD）,catalase（CAT） and content of malondialdehyde（MDA） in algae had been significantly affected under the organic toxicant exposure.The activities of SOD and CAT were increased at first and then decreased remarkably with the increasing concentration of the organic toxicant,showed as＂Bell Shaped Curve＂.The content of malondialdehyde（MDA） flared up and lipid peroxidant aggregated with the increasing concentration of the organic toxicant.The results suggested that the primary mechanism of two organic toxicants on Chlorella pyrenoidosa cells may be related to oxidation damage of lipid and other biological large molecules caused by dichloromethane and 1,2-dichloroethane.