Inhibitory effect of galloyl moiety in epigallocatechin gallate for gelation of gelatin

抄録

The combined use of epigallocatechin gallate (EGCG) and gelatin is a promising method to prepare usable gelatin-based materials for various industries. Nevertheless, the mechanisms of the molecular interaction between these substances have not been fully elucidated. This study aims to investigate the effect of EGCG on the gelation of gelatin using two different catechins, sol-gel transition analysis, and quartz crystal microbalance (QCM). First, 0-0.7 mg EGCG, having galloyl moiety, or epigallocatechin (EGC), lacking galloyl moiety, was dissolved in a 10 mg/mL gelatin solution. The sol-gel transition of each solution was evaluated at -20, 4, and 37°C. A high dose of EGCG hindered gelation at 4°C, whereas EGC did not. The QCM analysis demonstrated that a larger amount of EGCG was adsorbed onto gelatin than EGC. The results suggest that galloyl moiety contributes to the adsorption of EGCG to gelatin, leading to the impaired gelation of gelatin. These results provide a basis for the development of functional catechin-gelatin-based materials. (J Osaka Dent Univ 2020; 54: 251-255)