Flavonol glycosides isolated from the seeds of Lens culinaris inhibit dipeptidyl peptidase IV

Lens culinaris Medikus is a pulse crop of the family Fabaceae, and its edible seed is known as lentil. Lentil was reported to have diverse biological activities such as antioxidant, α-glucosidase–inhibitory, anti-inflammatory, and anticancer effects. In a previous phytochemical study, phenolics, flavonoids, tannins, saponins, and fatty acids were isolated from L. culinaris. As part of our ongoing search for functional resources from mutant cultivars developed by radiation breeding, our research group is cultivating gamma irradiated mutant lines of L. culinaris which are developed by various dose of gamma-irradiation from a labeled Cobalt (60Co) source on the seeds. To select the elite cultivar lines through the identification of active components of lentil, the n-butanol-soluble fraction of the seeds of L. culinaris was investigated and three known flavonol glycosides were isolated. All isolates were experimented with their DPP-IV inhibiting activities, using in vitro bioassay. The present result can be applied to the quality assurance of gamma irradiated mutant cultivar lines of L. culinaris, and also suggest that the selected elite mutant cultivars of L. culinaris serves as a promising source for natural anti-diabete compounds for application in the field of functional foods.