Applications of beta-gal-III isozyme from Bacillus coagulans RCS3, in lactose hydrolysis

作者：Batra Navneet^*; Singh Jagtar; Joshi Amit; Bhatia Sonu

来源：International Journal of Biological Macromolecules, 2011, 49(5): 879-884.

DOI：10.1016/j.ijbiomac.2011.08.004

• Lactose hydrolysis
• Bacillus coagulans
• beta-Galactosidase
• Thermostable
• Enzyme production

Bacillus coagulans RCS3 isolated from hot water springs secreted five isozymes i.e. beta-gal I-V of beta-galactosidase. beta-gal III isozyme was purified using DEAE cellulose and Sephadex G 100 column chromatography. Its molecular weight characterization showed a single band at 315 kD in Native PAGE, while two subunits of 50.1 and 53.7 kD in SDS PAGE. beta-Cal III had pH optima in the range of 6-7 and temperature optima at 65 degrees C. It preferred nitro-aryl-beta-D-galactoside as substrate having K(m) of 4.16 mM with ONPG. More than 85% and 80% hydrolysis of lactose (1-5%, w/v) was recorded within 48 h of incubation at 55 degrees C and 50 degrees C respectively and pH range of 6-7. About 78-86% hydrolysis of lactose in various brands of standardized milk was recorded at incubation temperature of 50 degrees C. These results marked the applications of beta-gal III in processing of milk/whey industry.

• 出版日期2011-12-1