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Title: Enzymatic modification of vegetable protein: immobilization of penicillium duponti enzyme on reconstituted collagen and the use of the immobilized-enzyme complex for solubilizing vegetable protein in a recycle reactor

Journal Article · · Biotechnol. Bioeng.; (United States)

Penicillium duponti enzyme was immobilized on reconstituted collagen by macromolecular complexation, impregnation, and covalent crosslinking techniques. The immobilization of the enzyme on collagen has a twofold purpose: 1) providing a protein microenvironment for the proteolytic enzyme; and 2) extending the useful life of the enzyme once immobilized on the collagen matrix. Two types of collagen were used, one produced by the United States Department of Agriculture and the other produced by FMC. The USDA collagen contained unhydrolyzed telopeptide linkages and required pretreatment to reduce collagenaselike activity of the enzyme. Activity analysis of the immobilized enzyme complex showed that membranes with enzyme loading less than 10 mg enzyme/gram of wet membrane in the reactor were dimensionally stable. The degree of crosslinking was an important parameter. Membranes with structural openings up to three times the initial dry thickness were found to be the maximum limit for controlled release of enzyme from the collagen membrane during enzymatic reaction. Higher activities and better stability of the enzyme in collagen membrane were found for covalent crosslinking of the enzyme to treated collagen films. The hydrolysis of soybean vegetable protein with the immobilized enzyme in a recycle reactor at enzyme loading of 7 mg/gram of wet membrane at 40 degrees Celcius, pH 3.4, produced 56.5% of soluble protein in 10 hours. The production is equivalent to 1.84 hours total contact time between the substrate and the immobilized enzyme. The average productivity based on a stable enzyme activity and 20 grams of dry membrane was 329 mg of protein/h/mg of active enzyme immobilized. The productivity of the free enzyme in a batch reactor was 62.5 mg protein/h/mg enzyme. (Refs. 14)

Research Organization:
Dept. Chem. Biochem. Eng., Rentgers Univ., New Brunswick, New Jersey 08903
OSTI ID:
5283390
Journal Information:
Biotechnol. Bioeng.; (United States), Vol. 23:11
Country of Publication:
United States
Language:
English