Exploration of ethanologenic bacteria from termite gut for bioethanol production

In contemporary times, there is considerable focus on lignocellulosic biomass-derived bioethanol production, owing to its multifaceted significance. Utilizing sugarcane bagasse as a substrate for bioethanol production presents an economically viable approach. In the present study, 0.5 M sodium hydroxide (NaOH) was employed for the removal of lignin during pretreatment, while blends of enzymes were employed to enhance the hydrolysis of carbohydrates, including cellulose and hemicellulose. Enzymes, including cellulases (endoglucanase and exoglucanase), xylanase, and laccase were sourced from Bacillus tequilensis KCTC13622(T) (isolated in this study). Crude enzymes were employed for the saccharification of delignified biomass, resulting in the production of a good amount of reducing sugars (6.722 mg/ml) and bioethanol production (0.6991 g/Lh) at a solid loading of 10%, 50 °C temperature, and 48 h time interval. This enzymatic hydrolysis process demonstrated efficient production of reducing sugars without the requirement for costly chemicals or commercial enzymes. The efficacy of the aforementioned delignification process was further corroborated through the characterization of substrates (both control and pretreated) employing scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction.