[Isolation, identification of lignin-degrading bacteria and purification of lignin peroxidase]

Two strains that could use lignin as sole carbon source and excrete peroxidases were isolated from activated sludge. Both strains are belonged to Pseudomanas based on morphological, physio-biochenical characterizatics and homology identification of 16S rDNA sequence, in which strain PKE117 is identified as a new species, while the strain PKE225 is identified as Pseudomanas thermaerum. Crude enzyme in liquid fermentation of PKE117 was analyzed with DEAE-cellulose 32 ion-exchanger resin chromatography and Sephadex G-75 gel-filtration in proper order. The lignin peroxidase specific activity increases from 0.87 U/mg to 204.5 U/mg, purification multiple is 235.1 and callback rate is 15%.