同化和共代谢降解氯苯菌株的筛选与特性研究  

Screening and characterization of an assimilation and co-metabolism-degrading chlorobenzene bacterial strain

作　　者：郭江枫 邢志林[1] 王永琼 曹昆 张学炼 苟芳 石云椿 刘莉莎 赵天涛[1] GUO Jiang-feng;XING Zhi-lin;WANG Yong-qiong;CAO Kun;ZHANG Xue-lian;GOU Fang;SHI Yun-chun;LIU Li-sha;ZHAO Tian-tao(College of Chemistry and Chemical Engineering,Chongqing University of Technology,Chongqing 400054,China)

机构地区：[1]重庆理工大学化学化工学院,重庆400054

出　　处：《中国环境科学》2021年第2期902-912,共11页China Environmental Science

基　　金：国家自然科学基金资助项目(51978117);重庆市技术创新与应用示范专项重点研发项目(stc2018jszx-zdyfxmX0019);重庆理工大学科研启动项目(2019ZD72);重庆理工大学研究生创新基金(ycx20192072)。

摘　　要：基于污染场地,筛选了一株可降解氯苯(CB)的微生物,经鉴定该菌株属于粘质沙雷氏菌属(Serratia marcescans),命名为Serratia marcescans TF-1.同化降解结果表明,该菌株能够在有氧的条件下以CB为唯一碳源和能源,菌体平均增长速率为0.0063~0.022g_(cell)/(mol_(CB)·h),最大比生长速率(μ_(max))为0.015~0.42h^(-1),CB降解速率(V_(CB))为1.35~4.47mol/(g_(cell)·h),菌株对CB最高耐受浓度高于200mg/L.共代谢降解结果显示,TF-1可以琥珀酸钠和柠檬酸钠为底物共代谢降解CB;氯苯浓度(c_(CB))<80mg/L时,μ_(max(柠檬酸钠))(0.21~0.87h^(-1))>μ_(max(琥珀酸钠))(0.20~0.81h^(-1)),V_(CB(柠檬酸钠))(0.15~0.47mol/(g_(cell)·h))<V_(CB(琥珀酸钠))(0.17~0.48mol/(g_(cell)·h));cCB>80mg/L时,μ_(max(柠檬酸钠))(0.086~0.21h^(-1))<μ_(max(琥珀酸钠))(0.17~0.25h^(-1)),V_(CB(柠檬酸钠))(0.61~1.11mol/(g_(cell)·h))>V_(CB(琥珀酸钠))(0.56~0.95mol/(g_(cell)·h)),表明共代谢降解过程中,CB浓度,底物种类是调控污染降解的重要因素.最后考察了温度、pH值和接种量对TF-1降解CB的影响,结果发现,该菌株适宜生长的温度范围为20~35℃,最适温度为30℃;适宜生长pH值为5~9,最适pH值为7;最适接种量为5%.与现有菌株比较发现TF-1的温度和pH值适用范围更广,降解能力更强,污染物耐受浓度更高,既能同化又能共代谢降解CB,在贫营养和富营养污染场地中应用潜力更大.本研究可为原位CB污染场地修复提供有效的生物资源.In this study,a novel chlorobenzene(CB)-degrading strain was isolated on the contaminated site and identified as Serratia marcescans TF-1.The assimilation degradation analysis showed that CB can be used by strain TF-1as the sole carbon source and energy under aerobic conditions,and the corresponding average growth rate,the maximum specific growth rate(μ_(max)),the CB degradation rate,and the maximum CB tolerance concentration were 0.0063~0.022g_(cell)/(mol_(CB)·h),0.015~0.42h^(-1),1.35~4.47mol/(g_(cell)·h),200mg/L,respectively.Moreover,sodium succinate and sodium citrate can be co-metabolized by strain TF-1as substrates.μ_(max(sodium citrate)),μ_(max(sodium succinate)),V_(CB(sodium citrate))and V_(CB(sodium succinate))were 0.21~0.87h^(-1),0.20~0.81h^(-1),0.15~0.47mol/(g_(cell)·h)and 0.17~0.48mol/(g_(cell)·h)respectively,when CB concentration was less than 80mg/L,andμ_(max(sodium citrate)),μ_(max(sodium succinate)),V_(CB(sodium citrate))and V_(CB(sodium succinate))were 0.086~0.21h^(-1),0.17~0.25h^(-1),0.61~1.11mol/(g_(cell)·h)and 0.56~0.95mol/(g_(cell)·h)respectively,when CB concentration was greater than 80mg/L.The results showed that the substrate type is the key factor in the co-metabolic degradation.Finally,the effects of temperature,pH and inoculation concentration on the degradation of CB by TF-1 were investigated.The results showed that the growth temperature and pH range of TF-1 were 20~35℃and 5~9,respectively.The optimal growth temperature of 30℃,pH of 7 and inoculation concentration of 5%were also obtained.The results indicated that TF-1 had a wider temperature and pH application range,stronger degradation ability,and higher tolerance to pollutant concentration.In addition,CB could be used directly or co-metabolized by strain TF-1,which was suitable for application in oligotrophic and eutrophic contaminated sites.This study provided effective biological resources for in-situ CB contaminated site remediation.

关 键 词：同化 共代谢 氯苯 功能菌 高耐受性 

分 类 号：X172[环境科学与工程—环境科学]