Hyperproduction of thermostable beta glucosidase by sporotrichum thermophile
Enzyme and Microbial Technology 9(12): 744-748
ISSN/ISBN: 0141-0229 Accession: 005603825
The effect of the growth of temperature, pH, carbon source, nitrogen supplementation and inoculum size were examined in shake-flask-scale studies to determine the optimum conditions for .beta.-glucosidases production by Sporotrichum (Chrysosporium) thermophile. Wheat bran and sugar-beet pulp were selected as the best carbon sources and (NH4)2SO4, NH4Cl and KNO3 as the best nitrogen supplementation. Ten liter fermentations were carried out to study the kinetics of product formation. It was found that S. thermophile is able to produce high thermostable extracellular cellobiase and aryl-.beta.-glucosidase. Very high aryl-.beta.-glucosidase (PNPG) activities in the range from 30 to 40 U ml-1 and cellobiase activities of 2,45 U ml-1 in the 3-day batch fermentations were obtained. The Km for aryl-.beta.-glucosidase and its thermal properties were also estimated.