中文摘要：

为了研究离子液体对微藻生长及生理特性的影响,以聚球藻7942（Synechococcus sp.PCC 7942）为实验材料,分析1-辛基-3-甲基咪唑溴盐（1-octyl-3-methylimidazolium bromide;[C8mim] Br）对其生长及生理特性的影响.结果表明：（1）[C8mim] Br严重抑制聚球藻的生长,这种抑制作用可能是由藻细胞膜被破坏引起的.（2）低浓度[C8mim] Br可诱导藻细胞合成超氧化物歧化酶（Superoxide dismutase,SOD）等可溶性蛋白,抵御[C8mim] Br的胁迫；但高浓度[C8mim] Br又会使SOD等酶活力降低.（3）随着[C8 mim] Br浓度的升高,藻细胞中丙二醛（Malondialdehyde,MDA）含量显著增加,表明细胞中活性氧自由基（Reactive oxygen species,ROS）过量积累,这将破坏聚球藻的细胞膜结构与功能,使细胞遭受严重损伤.因此,[C8mim] Br可通过破坏藻细胞膜的结构与功能,导致细胞变形、分裂,从而影响藻细胞的生长繁殖,这将为探讨[C8 mim] Br的毒性效应机制及其环境风险评价提供数据资料和科学依据.

英文摘要：

The growth and physiological characteristics of Synechococcus sp. PCC 7942 under different 1 - octyl- 3 -methylimidazolium bromide （[ C8mim] Br） concentrations were analyzed to exploit the effects of i- onic liquids on microalgae. The results showed that [ C8mim ] Br had a significant inhibition effect on the growth of Synechococcus sp. PCC 7942 ,which may be due to the destruction of microalgal cell membrane. Low concen- trations of [ C8mim] Br would induce the synthesis of soluble protein, such as superoxide dismutase （SOD）, which played an important role in the defense mechanism to protect cells from [ C8miml Br stresses;but high concentrations of [ C8mim] Br would cause the inactivation of SOD and decrease the protein contents. Moreo- ver,malondialdehyde （MDA） contents in Synechococcus sp. PCC 7942 were enhanced with the increase of[ C8 mim ] Br concentrations, showing that excessive accumulation of reactive oxygen species （ROS） damaged the structure and function of microalgal cell membrane. Therefore, under the stress of [ C8 mim ] Br, the structure and function of the microalgal cell membrane would be damaged by excessive ROS and [ C8mim] Br,which would lead to the inhibition of the microalgal growth. The results provide data for exploiting toxic mechanisms and evaluating environmental impacts of [ C8mim ] Br.