土壤微生物电化学系统降解四环素的机理

以四环素为研究对象，构建土壤微生物电化学系统（SMES），避光恒温培养58d后进行采样分析，研究了四环素降解、土壤理化性质、酶活性和三域微生物之间的内在联系，以揭示四环素在SMES中的生物降解机理.结果表明，采用SMES处理后，四环素降解率从52%显著提升至70%.与对照处理相比，脱氢酶活性在SMES中显著提升了144%，且与四环素降解率显著正相关.相比之下，在SMES中多酚氧化酶、过氧化氢酶和漆酶对四环素的降解效果微弱.pH值是影响土壤微生物群落的重要理化因子，且与四环素降解呈负相关关系.Network关联分析显示，真菌在四环素降解中起到关键作用，Geoalkalibacter、Microascus、Wardomyces和Scopulariopsis是四环素的潜在降解菌，其中Microascus和Scopulariopsis是脱氢酶的潜在分泌菌.

Mechanism of tetracycline degradation by soil microbial electrochemical systems

A soil microbial electrochemical system (SMES) was constructed to study tetracycline degradation, and the samples were collected after 58 days of incubation under dark and constant temperature conditions. The relationships among tetracycline degradation, soil physicochemical properties, enzyme activity and three-domain microorganisms were analyzed to reveal the biodegradation mechanism of tetracycline in the SMES. The results showed that the degradation rate of tetracycline was significantly increased to 70% from 52% by using the SMES. Compared with the control treatment, the activity of dehydrogenase in the SMES increased by 144%, and it was significantly positively correlated with tetracycline degradation. In contrast, weak tetracycline degradation by polyphenol oxidase, catalase and laccase was observed in the SMES. As an important physicochemical factor affecting soil microbial community, soil pH value was negatively correlated with tetracycline degradation. Network analysis showed that fungi played a key role in the degradation of tetracycline, the genera of Geoalkalicharacter, Microascus, Wardomyces and Scopulariopsis were potential degrading microorganisms of tetracycline, among which Microascus and Scopulariopsis may secrete dehydrogenase to degrade tetracycline.