1.Introduction b-Galactosidase(commonly known as b-lactase;EC 3.2.1.23)is a multifunctional enzyme that can catalyze the hydrolysis of terminal non-reducing b-D-galactose residues in b-D-galactosides or transfer the galactosyl residue to saccharide acceptors to yield galactooligosaccharides(GOS).b-Galactosidase has a variety of applications in food and medical industries such as hydrolysis of lactose in milk,manufacture of galactooligosaccharides(GOS)and treatment of lactose malabsorption[1].Although b-galactosidase is an ubiquitous enzyme existing in plants,animals and microorganisms,only a few b-galactosidases from Kluveromyces lactis,Aspergillus niger and Aspergillus oryzae are regarded as safe for food related industry applications.
Hongbing SunOlufemi Emmanuel BankefaIjeoma Onyinyechi IjeomaLiangtian MiaoTaicheng ZhuYin Li