Ethnopharmacological Investigation of Medicinal Plants from Gunung Sari Village, Indonesia, as Potential Dipeptidyl Peptidase-IV Inhibitors

A study on traditional antidiabetic remedies in Gunung Sari village, Bogor, Indonesia, investigated fifteen medicinal plants, which were collected and processed into crude extracts. Only three of these plants had been previously examined for their potential as dipeptidyl peptidase-IV (DPP-IV) inhibitors. Phytochemical quantification revealed total phenolic content (TPC) between 2.27±0.16 and 5.39±0.05 mg GAE/g extract, while total alkaloid content (TAC) ranged from 1.07±0.02 to 4.33±0.07 mg QE/g extract. Screening for DPP-IV inhibitory activity in vitro indicated that Piper ornatum demonstrated the strongest inhibition at 78.11±1.35%, whereas Syzygium polyanthum exhibited the weakest activity at 34.30±1.57% at 250 µg/mL. LC-HRMS analysis of the extracts identified at least eleven chemical constituents, including peaks tentatively corresponding to pipcrosides and crocatins, compounds previously isolated from Piper crocatum.