Plantagoside as Maillard reaction inhibitor—its inhibitory mechanism and application

An improvement of the Maillard reaction inhibitor screening system was carried out and led to the decrease of the background on fluorescent analysis with which we were able to perform the efficient screening, separation and purification of active compounds. As a result, plantagoside (Pl) (5,7,4′,5′-tetrahydroxyflavanone-3′-O-glucoside) from the seed of Plantago asiatica was isolated as an active compound. Plantagoside (Pl: IC50 1.2 μM) was about 90 times more potent than aminoguanidine (AG) which has been reported as a Maillard reaction inhibitor. We report on the structure–activity relationship, the effect for decline of an enzyme function by glycation and site and mechanism of action.