海洋菌群好氧共代谢降解酮洛芬特性研究

Study of aerobic co-metabolic degradation of ketoprofen by marine consortia

酮洛芬已在海洋环境中被广泛检出.为进一步了解海洋微生物对该化合物的降解特性,利用从海水中富集得到的YEP菌群研究其对20 mg/L酮洛芬的降解.结果表明,在以500 mg/L酵母浸粉为共代谢基质条件下,YEP菌群能够在36 h内好氧完全去除酮洛芬.在此过程中,YEP菌群分泌的铁载体能够将Fe(Ⅲ)还原成Fe(Ⅱ),Fe(Ⅱ)可与YEP菌群产生的H 2O 2反应生成OH.淬灭剂实验表明,OH参与了酮洛芬的降解.高效液相色谱-质谱分析表明,生物驱动的类芬顿反应生成的OH参与了酮洛芬的初始羟基化反应,产生新的中间代谢产物,然后通过酶催化反应实现对酮洛芬的矿化.高通量测序分析表明,Halomonas、Gracilimonas、Oceanimonas、Owenweeksia和Marinicella参与了生物驱动的类芬顿反应.研究结果为理解酮洛芬的生物降解机理及其在海洋环境中的归趋提供了理论依据.

Ketoprofen has been widely detected in the coastal environment.To study the characteristics of degradation of ketoprofen by marine microorganisms,the degradation of 20 mg/L ketoprofen is investigated by the enriched YEP consortium from seawater.The results show that YEP consortium is able to completely remove ketoprofen in 36 h under aerobic conditions when 500 mg/L yeast extract is used as a co-metabolic substance.During this process,the siderophores secreted by YEP consortium could reduce Fe(Ⅲ)to Fe(Ⅱ),which reacts with H 2O 2 generated by YEP consortium for OH production.Scavengers experiments show that OH participates in ketoprofen degradation.High performance liquid chromatography-mass spectrometry analysis shows that OH generated by biogenic Fenton-like reaction is involved in initial hydroxylation reaction of ketoprofen,generating new intermediate metabolites.Then ketoprofen could be mineralized via enzyme-catalyzed reactions.High throughput sequencing analysis shows that Halomonas,Gracilimonas,Oceanimonas,Owenweeksia and Marinicella participate in biogenic Fenton-like reaction.The study result provides a theoretical basis for understanding the mechanism of ketoprofen biodegradation and the fate of ketoprofen in marine environment.