Biomass conversion through optimization of cellulase from Chryseobacterium junjuense Bp17 and their utility in bioethanol production

Abstract

The search for economically viable and less laborous strategy for bioethanol production has increased globally in this quest bacterial cellulase treated biomass has been promising. Potential bacterium isolated from the forest soil near Bandipur of Karnataka, India exploiting its cellulolytic activity on the CMC agar medium. Molecular identification and characterization of isolate Bp17 revealed as Chryseobacterium junjuense Bp17. An optimization study, enhance the yield of the enzyme through varying parameters such as time, temperature, and pH. Enzymatic assays like β 1, 4 endoglucanase (148.55 U/ml), β 1, 4 exoglucanase (37.21 U/ml), and β glucosidase (42.21 U/ml) exhibit the enzyme activity. Endo, exo and β-glucosidase activities of hydrolyzed biomass broth like coconut husk; 212.88 ± 1.24 U/ml, 151.65 ± 1.24 U/ml and 176.63 ± 1.24 U/ml, rice bran; 223.72 ± 1.42 U/ml, 112.88 ± 1.42 U/ml and 133.43 ± 1.42 U/ml, Pongamia leaves; 389.69 ± 2.54 U/ml, 205.92 ± 2.54 and 187.99 ± 2.54 U/ml, and wood waste; 196.86 ± 0.2 U/ml, 138.90 ± 0.2 U/ml and 168.84 ± 0.2 U/ml, respectively. Hydrolyzed and control biomass differences analyzed through Scanning electron microscope (SEM), Energy dispersive X-ray (EDX), and Fourier transform infrared (FTIR) spectroscopy. Zymography reveals the activity and molecular weight of cellulolytic enzymes (40-130 KB). Hydrolyzed broth filtrate produced from biomass used as crude enzyme and further used for bioethanol production through the yeast fermentation process.