IDENTIFICATION AND CHARACTERIZATION OF PECTIC ENZYMES OF MCFARLIN CRANBERRY

Endo‐polygalacturonase activity was found in cranberry proteins. Viscosity measurements showed that the hydrolysis of pectins with both high and low methoxyl content occurred on addition of a protein dialysate to pectin solutions. The use of a phenol binding agent in the enzyme preparation was necessary to obtain a high hydrolytic activity. Higher activity was noted with citrus pectins than cranberry pectins. Optimum activity was found at pH 5.0 for cranberry polygalacturonase. Activity was destroyed after 35 min of heating at 100°C. Up to 0.6 M NaCl gave no significant effect on cranberry polygalacturonase activity at pH 5.0. Cranberry pectin esterase activity was low when compared to strawberry and tomato pectin esterase. The optimum pH value for pectin esterase was 7.5, and the enzyme was inactivated when heated for 5 min at 100°C. When pectin solutions were treated with NaCl, optimum pectin esterase activity occurred at 0.15 M concentration. Copyright © 1969, Wiley Blackwell. All rights reserved