镉胁迫对蚤状溞的生长及抗氧化酶活力的影响

Effects of Cadmium on Growth and Activities of Antioxidase in Daphnia Pulex

目的探讨蚤状溞作为指示生物监测镉污染的可行性。方法实验室条件下,研究Cd2+对蚤状溞的生长及总超氧化物歧化酶(T-SOD)、过氧化氢酶(CAT)和谷胱甘肽硫转移酶(GST)活力的影响。结果在亚致死浓度下,低质量浓度(0.0125 mg/L)Cd2+在短时间内对蚤状溞的生长具有促进作用;中、高质量浓度(0.025 mg/L及以上)Cd2+对蚤状溞生长则具有显著的抑制作用。在染毒12 h后3种酶活力各质量浓度组均比对照组有所下降;随着染毒时间的延长(24~72 h),低、中质量浓度组的酶活力呈现先升高再下降的趋势,而高质量浓度组的酶活力则一直低于对照组。结论以蚤状溞作为监测水体环境中Cd2+污染的指示生物是可行的。

Objectives To discuss the feasibility of using daphnia pulex as a marker of monitoring Cd2 + pollution in water surroundings. Methods The growth and activities of T-SOD,CAT and GST in daphnia pulex was used for monitoring the effect of Cd2 +in water under laboratory conditions. Results Under sub-lethal concentration of cadmium in water,the growth of daphnia pulex was promoted at low Cd2 +(0. 0125 mg/L) in short times,while inhibited prominently at moderate and high Cd2 +(0. 025 mg/L and 0. 05 mg/L). The activities of TSOD,CAT and GST in all treated groups were decreased at 12 h compared with the control group; the activities in low and moderate Cd2 +groups were increased at first and then downward with longer exposure time(in 24 ~ 72h), while the activities in high Cd2 +groups were lower than that in the control group all the time. Conclusions It is practicable of using daphnia pulex as a marker for monitoring Cd2 +pollution in water surroundings.