Cellulase Production from Bacillus Subtilis and Its Role in Saccharification of Alkali Pre-Treated Para Grass Biomass

Abstract

Production of second-generation bioethanol has created enormous interest globally as sustainable and ideal alternative source due to the gradual depletion of fossil fuels. In view of this, the present study was investigated to isolate cellulase producing bacterium from poultry soil sample and assess its role in the saccharification of Brachiaria mutica (Para grass). Initially, the cellulase producing bacterium was identified as Bacillus subtilis strain KPA based on biochemical and molecular characterization tools. Further, B. mutica was pre-treated using NaOH solution (4% w/v) and utilized for saccharification process as per the standard methodology. Results showed low impact of cellulase on untreated Para grass biomass with TRS yield of 2.24±0.18, 3.11±0.2, 4.1±0.17, 4.98±0.2, and 4.14±0.18 mg/g at 12, 24, 48, 72, and 96 h of treatment. The alkali (NaOH) pre-treated biomass exhibited maximum TRS yield of 3.23±0.2, 4.34±0.18, 5.25±0.17, 7.88±0.17, and 6.16±0.17 mg/g from 12-96 h. Similarly, the saccharification ability of untreated Para grass biomass was estimated lower than that of pre-treated one. The alkali pre-treated biomass showed maximum saccharification efficiency of 29.07±0.8, 39.06±0.8, 47.2±0.7, 70.9±0.7, and 55.4±0.8% in the presence of 4% (w/v) NaOH from 12-96 h. In conclusion, the findings suggested the prominent role of strain KPA-associated cellulase in the saccharification of B. mutica and its potential role in biofuel production in future.