Production of stable cellulase by Halobacillus VITPS2 using orange peels

Orange peel waste, rich in cellulose and hemicellulose, was utilized as a substrate for cellulase production using Halobacillus VITPS2, a halophilic bacterium adapted to high-salt environments. Pretreatment of the substrate, confirmed by thermogravimetric analysis and scanning electron microscopy, effectively removed lignin, enhancing saccharification efficiency. A fermentation medium containing 7% (w/v) orange peel and 1% (w/v) cellulose in Zobell Marine Broth yielded a maximum cellulase activity of 242 U/mL. Sequential chromatography produced cellulase with a specific activity of 421 U/mg. The enzyme exhibited optimal activity at pH 7.5 and maintained stability across a pH range of 6.5-8.0. Thermal stability analysis revealed consistent activity between 35-45 °C, and the enzyme remained active in the presence of 5% NaCl concentration. These properties underscore the enzyme's robustness and suitability for industrial applications, particularly in biofuel production. The present study integrates agro-industrial waste valorization with high-yield enzyme production, offering a scalable and eco-friendly biotechnological solution. This work contributes to sustainable bioprocessing for cellulase production and expanding the utility of halophilic bacteria in industrial biotechnology.