Metabolites of and : Diversity and α-Glucosidase Inhibitory Potential.

α-Glucosidase inhibitors are essential in the treatment of diabetes mellitus. Plant-derived drugs are promising sources of new compounds with glucosidase-inhibiting ability. The Jacq. and (L.) Kurtto & T.Erikss. herbs are used in many traditional medical systems to treat diabetes. In this study, metabolites of the and herbs in active growth, flowering, and fruiting stages were investigated using high-performance liquid chromatography with photodiode array and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS/MS). In total, 29 compounds in and 41 components in were identified including carbohydrates, organic acids, benzoic and ellagic acid derivatives, ellagitannins, flavonoids, and triterpenoids. Gemin A, miquelianin, niga-ichigoside F1, and 3,4-dihydroxybenzoic acid 4--glucoside were the dominant compounds in the herb, while guaiaverin, miquelianin, tellimagrandin II, casuarictin, and glucose were prevailing compounds in the herb. On the basis of HPLC activity-based profiling of the herb extract, the most pronounced inhibition of α-glucosidase was observed for gemin A and quercetin-3--glucuronide. The latter compound and quercetin-3--arabinoside demonstrated maximal inhibition of α-glucosidase in the herb extract. The obtained results confirm the prospects of using these plant compounds as possible sources of hypoglycemic nutraceuticals.