Decolorization of Distillery Effluent by Thermotolerant Bacillus subtilis
Soni Tiwari, Rajeeva Gaur, Priyanka Rai and Ashutosh Tripathi
DOI : 10.3844/ajassp.2012.798.806
American Journal of Applied Sciences
Volume 9, Issue 6
Problem statement: Ethanol production from sugarcane molasses generate large volume of effluent containing high Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) along with melanoidin, a color compound generally produced by “Millard reaction”. Melanodin is a recalcitrant compound degraded by specific microorganisms having ability to produce mono and di-oxygenases peroxidases, phenoxidases and laccases, are mainly responsible for degradation of complex aromatic hydrocarbons like color compound. These compounds causes several toxic effects on living system, therefore may be treated before disposal. Approach: The purpose of this study was to isolate a potential thermotolerant melanoidin decolorizing bacterium from natural resources for treatment of distillery effluent at industrial level. Results: Total 10 isolates were screened on solid medium containing molasses pigments. Three potential melanoidin decolorizing thermotolerant bacterial isolates identified as Bacillus subtilis, Bacillus cereus and Pseudomonas sp. were further optimized for decolorization at different physico-chemical and nutritional level. Out of these three, Bacillus subtilis showed maximum decolorization (85%) at 45°C using (w/v) 0.1%, glucose; 0.1%, peptone; 0.05%, MgSO4; 0.01%, KH2PO4; pH-6.0 within 24h of incubation under static condition. Conclusion/Recommendations: The strain of Bacillus subtilis can tolerate higher temperature and required very less carbon (0.1%, w/v) and nitrogen sources (0.1%, w/v) in submerged fermentation. It can be utilized for melanoidin decolorization of distillery effluent at industrial scale.
© 2012 Soni Tiwari, Rajeeva Gaur, Priyanka Rai and Ashutosh Tripathi. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.