A novel strain of Aspergillus niger producing a cocktail of hydrolytic depolymerising enzymes for the production of second generation biofuels

Abstract

The screening and isolation of fungi producing a cocktail of hydrolytic enzymes was studied. Among the various isolates obtained from different soil samples, a strain NS-2 was selected. The phylogenetic analysis of this strain showed highest homology (99%) with Aspergillus niger. It was capable of producing cellulolytic, hemicellulolytic, amylolytic, and pectinolytic enzymes in appreciable titers on wheat bran based liquid and solid state media. The mixture of enzymes produced by this organism could effectively hydrolyze various domestic waste residues, revealing conversion efficiencies of 89 to 92% and produced high reducing sugar yields of 0.48 to 0.66 g/g of dry residue. This enzyme cocktail could potentially find a significant application in the conversion of agricultural and other waste residues having cellulose, hemicellulose, starch, and pectin as carbohydrates to produce simpler sugars which can be fermented for the production of second generation biofuels.