Effect of soaking and germination on polyphenol content and polyphenol oxidase activity of mung bean (Phaseolus Aureus L.) cultivars differing in seed color

Abstract

Five mung bean cultivars varying in seed coat color were analyzed for polyphenol content. The effect of soaking and germination on the polyphenol content and polyphenol oxidase activity was investigated. The level of total polyphenols was found to be in the range of 310-340 mg/100 g in whole seeds. Soaking reduced the total polyphenols, whereas germination for 48 h increased total polyphenol content by 41-76%. The hydrolysable tannins, condensed tannins, and hydrolysable tannins/condensed tannins index increased with an increase in period of germination. The total and percent condensed tannins content slightly decreased while hydrolysable tannins increased during germination. Maximum polyphenol oxidase activity of 102-108 units was observed in 24 h germinated seeds. There was no significant correlation found between the polyphenolic content and polyphenol oxidase activity in germinating mung bean seeds. These findings demonstrated that the mung beans are fair sources of polyphenols, thus having great potential as a source of natural antioxidants. Copyright © Taylor and Francis Group, LLC.