Evaluation of designed consortium SNH-1 for efficient hydrolysis of agriculture waste to benefit bioethanol production

Abstract

An environment friendly and cost-effective approach is a major bottleneck in biofuels production from agriculture waste residue. The present study unravels the enzymatic hydrolytic potential of a designed bacterial consortium (SNH-1) comprised of camel rumen derived B. safensis CRN 13, B. subtilis CRN 16, C. braakii CRN 21, B. circulans CRN 24, and P. dendritiformis CRN18. The consortium SNH-1 was evaluated for exo-glucanase (0.29 U/ml), β-glucosidase (0.69U/ml), β-glucuronidase (0.29U/ml), endoxylanase (0.79U/ml), arabinosidase (0.62U/ml), α-galactosidase (0.36 U/ml), and endoglucanase (0.51U/ml) activity. Genome analysis of consortium members identified 660 carbohydrate-active enzymes (CAZyme) responsible for breaking the structural intricacy. These include 296 glycoside hydrolase, 19 auxiliary activity, 186 glycosyl transferases, and 37 carbohydrate-binding modules genes. The designed consortium hydrolyzed sugarcane bagasse, wheat straw, and rice straw effectively. Response surface methodology (RSM) was applied to optimize the pH, temperature, and substrate concentration, which has resulted in a 23% higher saccharification of wheat straw. Further, 6.2% bioethanol production was estimated from wheat straw hydrolysate using S. cerevisiae. The wheat straw saccharification by the designed consortium is a cost-effective, chemical-free, cleaner, and promising approach for producing lignocellulosic bioethanol.