A bioprocess for the remediation of anaerobically digested molasses spentwash from biogas plant and simultaneous production of lactic acid

A bacterial isolate LAB-1 identified as Lactobacillus casei was cultivated in a fermentation medium containing biogas plant effluent. This effluent wa s generated after anaerobic digestion of molasses spentwash in biogas ferme nters. In the bioremediation process of this very dark coloured effluent th rough the cultivation of L. casei, decrease in effluent's colour of 49 and 52% and reduction in COD level up to 54 and 57% were achieved using bacteri al cells in free and immobilised system, respectively, in 5 days batch cult ivation. During this process of bioremediation, a metabolite lactic acid wa s produced by this bacterial isolate with the yield of 10.9 and 11.3 mg/ml, in free and immobilised cells fermentation, respectively.