Purification, characterization and thermodynamic analysis of cellulases produced from Thermomyces dupontii and its industrial applications

Cellulases involved in the hydrolysis of cellulose and plays a vital role in different industries like textile, detergent paper and Feed industry. Cellulases have been a prospective target for research by both the academic and industrial sectors because of the intricacy of the enzyme system and the enormous industrial potential. In the present work Thermomyces dupontii, which had previously been isolated and recorded as a promising cellulase producer were used. Both endoglucanases and betaglucosidases were purified to its homogeneity by ammonium sulfate followed by anion exchange and gel filtration chromatography. The recovery and purification fold for endoglucanases and betaglucosidases were 13.7, 10.7 % and 5.9, 2.7, respectively. The molecular weight of endoglucanases and betaglucosidases were estimated as 37 and 66 kDa on SDS-PAGE. Upon kinetic analysis the purified endoglucanases and betaglucosidases showed Km 0.63; 28.56 mg/ml and Vmax 82; 80 U/ml/min, respectively. Characterization revealed that enzyme was found to be acidophilic cellulase having optimal pH of 5.5 and 70 ⁰C. Furthermore, cellulases were accelerated in the presence of Ca(2+) and EDTA. The cellulases had activation energy (Ea) of −44.55; −50.02 kJ/mol for carboxy-methyl-cellulose hydrolysis and Enthalpy (ΔH) 42.20; 47.70 kJ/mol and entropy ΔS −5.1 and −5.7 kJ/mol for EG and BGL, respectively. In addition to this the enzyme had a secondary structure of protein as represented by FTIR spectrum The current study suggested that purified cellulases can be used as a detergent additive to improve washing. Furthermore, it shows the biostoning ability when applied on jean fabric.