Bioremediation potential of newly isolated Bacillus albus strain VKDS9 for decolourization and detoxification of biomethanated distillery effluent and its metabolites characterization for environmental sustainability

In India, the environment friendly and sustainable management of colored effluents emanating from alcohol-producing distilleries has become a serious environmental concern. The current study aimed to examine the efficiency of ligninolytic enzyme-producing bacterial strain isolated from ameliorated distillery sludge by enrichment method for its bioremediation and detoxification potential of biomethanated distillery effluent (BMDE). Out of nineteen bacterial isolates isolated from distillery sludge, one strain VKDS9, having higher ability towards the removal of effluent's color, was identified as Bacillus albus by 16S rRNA analysis. The bacterium showed significant decolourization of effluent up to 83% with subsequent reduction of biochemical oxygen demand (3261 mg/L), chemical oxygen demand (7870.5 mg/L), and other physico-chemical parameters including metallic and non-metallic elements in the presence of glucose (1% w/v) and peptone (0.5% w/v) at optimal temperature 37 degrees C, pH 8.0, and 180 rpm within 144 h. Further, biodegradation of effluent was confirmed by high performance liquid chromatography analysis that showed appearance/disappearance and reduction of several peaks. Moreover, GC-MS analysis of bacterial treated effluent displayed the disappearance of several chemical contaminants and formation of new metabolites which were formed as end products of biodegraded effluent. Furthermore, phytotoxicity of treated and untreated BMDE was evaluated using Cicer arientinum L. seeds revealed the biodetoxification of BMDE after treatment by B. albus strain VKDS9. This study concluded that B. albus strain VKDS9 can be used as an efficient biotechnological tool for remediation of distillery effluent for its harmless dumping into the environment towards sustainable development. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

In this study, a ligninolytic enzyme-producing bacterial strain was isolated and used for the bioremediation and detoxification of biomethanated distillery effluent. The strain showed efficient decolourization of the effluent and reduction of biochemical oxygen demand and chemical oxygen demand. The analysis confirmed the biodegradation of the effluent and the formation of new metabolites. Phytotoxicity assessment also revealed the reduction of toxicity after treatment.