Efficient valorization of waste glycerol to 2,3-butanediol using Enterobacter cloacae TERI BD 18 as a biocatalyst

This study demonstrates the effective use of a bacterial isolate as a biocatalyst converting wastes to 2,3-butanediol. The developed microbial catalyst Enterobacter cloacae TERI BD 18 was robust as it can grow in wastes with high concentration of impurities showing the potential for developing an integrated biorefinery process for producing 2,3-butanediol. Valorization of rice straw, waste glycerol, molasses, distillery effluent, dairy waste and waste gas was observed. Maximum 2,3-BD production was observed at initial pH 7, temperature 37 degrees C, agitation speed of 350 rpm and 3% inoculum size. The production of 41.44 g L-1 of 2,3-BD with a yield 0.48 g g(-1) was achieved in 13L bioreactor using waste glycerol as a sole source of carbon. An ecofriendly and green method for 2,3-BD production has been proposed by implementing wild type bacterial strain E. cloacae TERI BD 18 as biocatalyst utilizing wastes as feedstock (with no added nutrients) in 13L bioreactor.