Preparation of active corn peptides from zein through double enzymes immobilized with calcium alginate–chitosan beads
•Alcalase and trypsin were firstly co-immobilized on calcium alginate–chitosan composite carrier.•The storage stability and reusability were greatly improved after immobilization.•The immobilized enzymes retained high activity in alcoholic solution.•Active corn peptides were obtained by the immobilized enzymes in alcoholic solution.
Double enzymes (alcalase and trypsin) were effectively immobilized in a composite carrier (calcium alginate–chitosan) to produce immobilized enzyme beads referred to as ATCC. The immobilization conditions for ATCC were optimized, and the immobilized enzyme beads were characterized. The optimal immobilization conditions were 2.5% of sodium alginate, 10:4 sodium alginate to the double enzymes, 3:7 chitosan solution to CaCl2 and 2.5 h immobilization time. The ATCC beads had greatly enhanced stability and good usability compared with the free form. The ATCC residual activity was retained at 88.9% of DH (degree of hydrolysis) after 35 days of storage, and 36.0% of residual activity was retained after three cycles of use. The beads showed a higher zein DH (65.8%) compared with a single enzyme immobilized in the calcium alginate beads (45.5%) or free enzyme (49.3%). The ATCC kinetic parameters Vmax and apparent Km were 32.3 mL/min and 456.62 g−1, respectively. Active corn peptides (CPs) with good antioxidant activity were obtained from zein in the ethanol phase. The ATCC might be valuable for preparing CPs and industrial applications.
Journal: Process Biochemistry - Volume 49, Issue 10, October 2014, Pages 1682–1690