Valorization of Agro-industrial Discards in Fermentation for the Production of Cellulase Enzyme

Abstract

Cellulases are commercially important enzymes with application in various industries such as biofuel, detergent, food processing, brewery, pulp and paper. To make its production cost-effective, a preferred method is to use solid-state fermentation and with use of inexpensive substrates. Solid-state fermentation is an alternative culturing method and yields higher enzymes compared to submerged fermentation. In the current study, Aspergillus niger was isolated and further developed as inoculum for solid-state fermentation. Agroindustrial discards like banana pseudostem, jackfruit waste were used as the substrates. The substrates were pretreated by acid and were characterized by FTIR analysis to confirm the presence of cellulosic content. Different concentrations of the substrates were attempted for fermentation and the yield of the enzyme was compared. The solid-state fermentation was stable for enzyme production as well as microbial growth. The cellulase activity per gram of the substrate (U/g) was obtained maximum for jackfruit waste-based media (17±1.1 U/g). Both the lignocellulosic substrates were potential substrates for the production of cellulase enzyme. With further optimization and scale-up, this could be a cheap and sustainable process. This study has validated agro-industrial waste’s bioconversion into value-added products that have a remarkable environmental and economic advantage.