title: Immobilization and characterization of beta-galactosidase from the plant gram chicken bean (Cicer arietinum). Evolution of its enzymatic actions in the hydrolysis of lactose.
abstract: beta-Galactosidase (beta-D-galactosidase galactohydrolase, EC 3.2.1. 23) isolated and purified from gram chicken bean was immobilized on cross-linked polyacrylamide gel. The activity yield was high and attained up to 72%. Compared with the free enzyme, the immobilized enzyme had a wider operational pH range and better thermal stability. Lyophilized pieces exhibited good stability when stored at room temperature for 60 days and a favorable operational stability when used eight times repeatedly without loss of enzymatic activity under the same conditions. Kinetic data (K(m), V(m), and E(a)) for the free and the immobilized enzymes were determined using O-nitrophenyl-beta-D-galactoside (ONPG) and lactose as substrates. The result of time courses of hydrolysis of lactose showed that beta-galactosidase from the plant gram chicken bean would have a promising application in the hydrolysis of lactose in milk.
authors.affiliation: Department of Chemistry, Lanzhou University, Lanzhou 730000, People's Republic of China.
authors.forename: S
authors.initials: S
authors.lastname: Sun
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: S
authors.initials: S
authors.lastname: Nu
authors.forename: X
authors.initials: X
authors.lastname: You
mesh_terms: D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D007887:Fabaceae / Q000201:enzymology*; D006868:Hydrolysis; D007700:Kinetics; D007785:Lactose / Q000378:metabolism; D010946:Plants, Medicinal; D012639:Seeds / Q000201:enzymology; D013816:Thermodynamics; D001616:beta-Galactosidase / Q000737:chemistry / Q000378:metabolism*
chemical_list: D004800:Enzymes, Immobilized; D001616:beta-Galactosidase; D007785:Lactose