Ethanol Production by Mucor Indicus Using the Fungal Autolysate as a Nutrient Supplement

Abstract

To develop a cost-effective fermentation medium, fungal extract (FE) of Mucor indicus biomass, which is a by-product of fermentation processes, was evaluated as a nutrient source for ethanol production by the fungus. Autolysis as a natural process of self-digestion of fungal cells was used to release the nutrients in surrounding medium leading to the production of the FE. Glucose consumption and ethanol production were followed using several media made with different concentrations of FE as nutrient supplementation replacing either yeast extract (YE) or whole nutrient. According to the results, 5 g/L YE could be successfully replaced with 5 g/L FE, resulting in higher ethanol yield (0.46 g/g) and productivity (0.69 g/L.h). Yield of glycerol production, the major byproduct of fermentation, was also increased by supplementation of the FE.