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Gupta, G., Sahai, V., and Gupta, R. K. (2014). "Thermal stability and thermodynamics of xylanase from Melanocarpus albomyces in presence of polyols and salts," BioRes. 9(4), 5801-5816.

Abstract

An extracellular xylanase from the thermophilic fungus Melanocarpus albomyces IIS 68 was evaluated for its activity and stability in the presence of polyols and salts at 60 °C, and found to be an effective protecting agent for thermal deactivation of enzyme. Response surface methodology was employed to study the synergistic effects of glycerol and NaCl (thermo-stabilizers) for xylanase stability. The addition of these thermo-stabilizers resulted in more than a 10-fold increment in enzyme half-life. Activation energy (Ea) and thermodynamic parameters such as ∆H, ∆G, and ∆S were calculated for the thermal inactivation of free and immobilized xylanase. The immobilized enzyme underwent substantially less conformational changes because of its enhanced stability and increased compactness, providing better thermo-stability at elevated temperatures. These findings suggest that the combined effect of glycerol and sodium chloride serves as a potential stabilizer for extracellular thermophilic xylanase, which finds commercial application in many industries, especially in the pulp and paper industry.
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