Detection of persistent organic compounds from biomethanated distillery spent wash (BMDS) and their degradation by manganese peroxidase and laccase producing bacterial strains.

ABSTRACT

Biomethanated distillery spent wash (BMDS) retains dark black colour with complex persistent organic pollutants even after anaerobic treatment. The specific ratio (4311) of Proteus mirabilis (FJ581028), Bacillus sp. (FJ581030), Raoultella planticola (GU329705) and Enterobacter sakazakii (FJ581031) decolourised BMDS up to 76% within 192 hr along with degradation of persistent organic compounds in presence of glucose (1%) and peptone (0.1%). The colour removal ability was noted due to ligninolytic enzyme activity. Where the maximum manganese peroxidase was 1.93 U ml-1 and laccase activity equalled 0.84 U ml-1. The gas chromatography–mass spectrophotometry (GC–MS) analysis confirmed the direct correlation between colourant and persistent organic pollutants due to simultaneous reduction of colour and pollutants present in BMDS. The seed germination test showed reduction of 75% toxicity after bacterial treatment process.