Isolation and identification of a novel cellulolytic bacterium and optimization of FPase production for bagasse hydrolysis.

Abstract

The current study's primary objectives were to screen for novel FPase-producing bacteria and optimize hydrolysis conditions for alkali-thermally pretreated sugarcane bagasse. This study carefully screened cellulolytic bacteria from soil and identified KH-08 as a potent FPase-producing strain. Based on 16S ribosomal RNA and gyrA gene sequences, KH-08 was identified as Bacillus velezensis, a newly found microbe capable of producing FPase. Experiments were conducted to optimize FPase-producing parameters such as fermentation time, temperature, and pH. The study improved FPase output by refining these parameters using Box-Behnken Design (BBD) and Response Surface Methodology (RSM). The derived quadratic polynomial model demonstrated great dependability (R² = 99.8%) and interactions that are statistically significant (P < 0.05). The ideal fermentation conditions-6 days, 30 °C, and pH 6.5-resulted in the greatest FPase activity of 75.93 U/L. The remarkable enzyme yield achieved under mild conditions clearly demonstrates the superiority of Bacillus velezensis KH-08 over previously reported cellulolytic strains. This exceptional performance underscores its potential as a highly promising candidate for industrial-scale bioconversion, with direct implications for bioethanol production, biomass valorization, and waste to energy technologies.