摘要
邻苯二甲酸二丁酯(Di-n-butyl phthalate,DBP)是一种广泛存在于环境中的有机污染物,对环境构成严重威胁,现已被中国环境监测中心列入优先控制污染物名单。本研究从黑土中分离出两种典型细菌B.subtilis D13和E.coli Q5,以液体培养法接种于添加不同质量浓度(0、5、10、20、40、80 mg·L^(-1))DBP的LB培养基中,测定两种菌株的生长曲线;以分光光度法测定其氧化应激酶系对DBP胁迫的应答反应。结果表明,(1)DBP污染可抑制细菌生长,在对数生长期抑制作用显著,但随着污染时间的延长,B.subtilis D13菌株生长量呈恢复趋势,抑制作用减缓;DBP污染对E.coli Q5的抑制作用更为显著,且菌株生长未出现恢复趋势。(2)经DBP培养,6 h时两种菌株的抗氧化应激酶对污染出现应答反应,SOD活性随着污染物浓度的升高而增加。(3)两种细菌的CAT、GST活性与SOD活性的变化趋势基本一致,酶活呈现DBP低浓度诱导而高浓度抑制的趋势。实验结果可为进一步研究DBP对微生物的生态毒理效应提供理论基础。
Di-n-butyl phthalate （DBP） is a ubiquitous organic pollutant in black soil. Because it is widely detected in China’s agricultural soil, DBP has been listed as an environmental priority pollutant by China State Environmental Protection Administration. The purpose of the study was to estimate the responses of the growth and activities of oxidative enzymes to DBP with various concentration in B. subtilis D13 （a typical gram-positive bacterium） and E. coli Q5 （a typical gram-negative bacterium） by liquid cultivation and spectrophotometry. The results showed that： （1） the growth of two strains were inhibited by DBP, the effect was more significant at the logarithmic phase. Along with the increase of time, the growth of B. subtilis D13 had recovered, however, E. coli Q5 was not, it appeared more sensitive to DBP than the B. subtilis D13 did. （2） The activities of SOD in the two typical bacteria were increased along with the increase of DBP concentration, which meant that activities of SOD could be correlated to the impact of DBP in B. subtilis D13 and E. coli Q5. （3） Similarly, the trend on the activities of CAT and GST was basically consistent with that on SOD in the two bacteria, that is, the low concentration of DBP could promote enzyme activity, however, and the high concentration of DBP could reduce the activity. The result provides an important basis for further study on the toxicological effect of DBP on microorganisms.
出处
《生态环境学报》
CSCD
北大核心
2016年第7期1225-1229,共5页
Ecology and Environmental Sciences
基金
黑龙江省青年基金项目(QC2013C032)
