摘要
为了研究环境中抗生素对4-氯硝基苯(4-chloro-1-nitrobenzene,4-CNB)生物降解的影响,本文选用9种高效降解4-CNB的菌株开展试验,并通过药敏试验研究了18种常用抗生素对菌株CT1的最小抑菌浓度(Minimum inhibitory concentration,MIC)。采用4-CNB-环丙沙星联合培养,研究了不同浓度环丙沙星作用下菌体浓度、细胞活性、总超氧化物歧化酶(SOD)及降解性能的变化。结果表明:睾丸酮丛毛单胞菌CT1降解4-CNB效率最高,27℃9 h降解效率为98.4%±0.2%。仅6种抗生素存在MIC值,其中环丙沙星的MIC值最低,为4μg·mL^(-1);链霉素MIC最高,为64μg·mL^(-1)。加入低浓度环丙沙星(1/4 MIC),菌体浓度和细胞活性显著降低,4-CNB降解率下降至87.0%±3.3%,环丙沙星浓度高于最小抑菌浓度(4 MIC)时,菌株生长受到极大抑制,4-CNB降解率仅为35.7%±3.9%。SOD酶活结果显示,加入环丙沙星能显著降低菌体细胞的SOD酶活力,引起活性氧对菌体的损伤,因此环丙沙星导致的菌体细胞内SOD酶活力降低可能是4-CNB生物降解受到抑制的主要原因之一。
To investigate the effect of antibiotics on the biodegradation of 4-chloro-1-nitrobenzene(4-CNB)in the environment,nine bacterial strains that can efficiently degrade 4-CNB were selected.The minimum inhibitory concentrations(MICs)of the 18 common antibiotics to CT1 were studied using a drug sensitivity test.The results showed that the degradation efficiency of 4-CNB by Comamonas testosterone CT1 was the highest,with a degradation efficiency of 98.4%±0.2%at 27℃for 9 h.Only six antibiotics had MICs,among which ciprofloxacin had the lowest(4μg·mL^(-1))and streptomycin had the highest(64μg·mL^(-1)).The effects of different concentrations of ciprofloxacin on cell concentration and activity,and the activity of total superoxide dismutase(SOD)and degradation were studied using 4-CNB-ciprofloxacin co-culture.When low concentration ciprofloxacin(1/4 MIC)was added,the cell concentration and activity decreased significantly,and the degradation rate of 4-CNB decreased to 87.0%±3.3%.When the concentration of ciprofloxacin was higher than the MIC(4 MIC),the strain barely grew,and the degradation rate of 4-CNB was only 35.7%±3.9%.The addition of ciprofloxacin significantly decreased SOD activity and caused damage to the reactive oxygen species.Therefore,the decrease of SOD activity caused by ciprofloxacin might be one of the main reasons for the inhibition of 4-CNB biodegradation.
作者
刘勇豪
徐淼
吴铭
罗俊
尚佳歧
郭立泉
LIU Yonghao;XU Miao;WU Ming;LUO Jun;SHANG Jiaqi;GUO Liquan(Key Laboratory of Straw Biology and Higher Value Application,Ministry of Education,College of Life Science,Jilin Agricultural University,Changchun 130118,China;National Environmental Protection Wetland Ecology and Vegetation Restoration Key Laboratory,School of Environment,Northeast Normal University,Changchun 130024,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2021年第8期1659-1666,共8页
Journal of Agro-Environment Science
基金
国家环境保护湿地生态与植被恢复重点实验室课题项目(2019-001)
吉林省预算内基本建设资金项目(2019C055-2)
吉林省教育厅科学研究项目(JJKH20200323KJ)。
