Revista de biorremediación y biodegradación

Abstracto

Isolation of Clostridium sp. and its Use in Degrading Pyrene under Anaerobic Condition

Lian Li, Jun Zhou, Xiang Li, Peiru Zhu, Chaoba Lin, Jiayang Liu, Xueying Zhang

A novel Clostridium (LZ25) strain was isolated and characterized from oil-contaminated anaerobic sludge and employed to degrade pyrene for environmental purpose. Cultivation process parameters, including pH value, temperature, pyrene concentration, and inoculums, were studied with the aim of improving biodegradation efficiency. The bacterium was capable of using pyrene as the sole carbon source for biomass growth, during which more than 40% of pyrene was biodegraded at an initial pyrene concentration of 50 mg/L and inoculum of 10-20% (v/v). By analysis with GC-MS, pyrene was reduced to 4,5-dihydropyrene and then phenanthrene, which was subsequently degraded to 1,1'-(1-butenyl)biphenyl. Three different products, namely, benzoestrol, 2'-hydroxy-4'methylacetophenone, and cinnamyl alcohol, were potentially generated on the basis of 1,1'-(1-butenyl)biphenyl. These three intermediates might go through further transformation and eventually form phenol and protocatechuic acid. These findings show Clostridium sp. LZ25 can be a promising microbial cell factory for effective biodegradation of pyrene in industrial wastewater.