Production, purification, characterization, immobilization, and application of β‐galactosidase: a review

Biopharmaceuticals are new categorizing biomolecules, which are the results of incredible proliferation in the field of biotechnology. One of the challenging biomolecule β-galactosidase (β-galactosidase galacto hydrolysase, trivially lactase) catalyzes hydrolysis of lactose to produce glucose and galactose, and in some cases, it takes part in transgalactosylation reaction that produces functional food galato-oligosaccharide. A wide variety of strategies had been already attempted for production of β-galactosidase through fermentative route. Beside the upstream process, downstream technology towards purification and immobilization of target enzyme also create great attentions. Subsequently, its wide applications in the field of food, biopharmaceuticals, dairy, diagnosis, and waste treatment boost up biotechnological economy as well as zero-effluent discharge. In dairy industry, β-galactosidase has been used to degrade lactose, prevent crystallization of lactose, improve sweetness, and increase the solubility of milk product, otherwise which would be an environmental pollutant. In food and pharmaceutical industries, β-galactosidase has been used to prepare low lactose-containing food products for low lactose-tolerant people. Therefore, it is obvious to elucidate different technological aspects of β-galactosidase, which may provide a great knowledge in educational and industrial field. Taking the enzyme into account, a ready review has been made about its production, purification, characterization, and immobilization technology. The review also addresses wide applications of β-galactosidase in different fields. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.

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