土壤镉诱导赤子爱胜蚓的氧化损伤、防御反应及其致毒阈值  

Oxidative damage,defense response and toxicity threshold in Eisenia foetida exposed to cadmium-polluted soils

作　　者：丁龙[1,2] 李冬冬[2] 汪承润[2] 石健[2] 郭晨[2] 钱燕[2] 马清萍 张凯[2] 

机构地区：[1]安徽大学生命科学学院,合肥230601 [2]淮南师范学院生命科学系,淮南232001

出　　处：《环境化学》2014年第7期1115-1122,共8页Environmental Chemistry

基　　金：安徽省自然科学基金项目(1208085MB17);污染控制与资源化研究国家重点实验室开放课题项目(PCRRF10020;PCRRF12014);安徽省高校省级自然科学研究项目(KJ2012Z381)资助

摘　　要：为探索镉(Cd)污染土壤的生态安全性及其早期预警的敏感生物标志物,研究了赤子爱胜蚓(Eisenia foetida)暴露于外源Cd污染土壤(0、0.16、0.31、0.63、1.25、2.5、5.0、10.0、20.0 mg·kg-1)15 d后蚯蚓抗氧化酶、氧化损伤蛋白及其相关代谢酶的变化.结果表明,随着土壤有效态的升高,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)同工酶及其酶活性与内肽酶同工酶活性基本呈现先降低、后升高和再下降的变化,而蛋白羰基化产物则呈现相反的变化趋势.同时,愈创木酚过氧化物酶(POD)同工酶及其酶活性则呈现"U"型剂量效应.因此,土壤镉诱导了蚯蚓氧化损伤的Hormesis效应.与4种抗氧化酶比较,蛋白羰基化产物的敏感性更高,据此推测土壤Cd的致毒阈值为0.073 mg·kg-1有效态Cd.In order to investigate the ecological risk and sensitive biomarkers for early warning of cadmium （Cd）-polluted soils, earthworms Eisenia fetida were subjected to extraneous Cd-added soils （0, 0.16, 0.31, 0.63, 1.25, 2.5, 5.0, 10.0 and 20.0 mg.kg^-1） for 15 days, and antioxidant enzyme systems, oxidative damage proteins and related catabolic enzyme were purposely examined in the earthworms. The results showed that, along with the increase of available Cd in the soils, in general, isozymes and affiliated activities of superoxide dismutase （SOD） , catalase （CAT）, and ascorbate peroxidase （APX）, as well as endoprotease （EP） isozymes decreased slightly, followed by evident enhancement and reduction, whereas carbonylated proteins altered inversely. Meanwhile, guaiacol peroxidase （ POD ） isozymes Therefore, Cd induced hormetic effects and activities changed as a “U”-shaped dose response of oxidative damag carbonylated proteins responded more sensitively than the Based on the results, it is suggested that the potential available Cd in the present Cd-polluted soils. es in the earthworms. Comparatively, the antioxidant enzymes to the soil Cd stress. toxicity threshold was 0.073 mg.kg^-1 of available Cd in the present Cd-polluted soils.

关 键 词：赤子爱胜蚓(Eisenia foetida) 镉 氧化损伤 生物标志物 生态风险 

分 类 号：X174[环境科学与工程—环境科学] X53