Résumé
Ethnomedicinal survey documents the traditional practices of Tetrastigma angustifolia leaves in the management of diabetes in the North-eastern region of India. The present study was aimed at isolation of possible antidiabetic principle(s) from T. angustifolia leaves and evaluation of antidiabetic efficacy of isolated compound(s) in experimental animal model. The methanolic extract of T. angustifolia leaves was obtained by Soxhlet extraction method and subjected to silica gel column chromatography (100-200 mesh). Fraction 18-176 chloroform:methanol (70:30) yielded a pale yellow colored compound. The structure of pure compound was elucidated with the help of UV, IR, NMR and Mass spectrometric/techniques. The antioxidant activity of the isolated compound was evaluated in vitro by various radical scavenfing assay methods.. Oral acute toxicity study was carried out according to OECD guideline 423 in Wistar rats. The antidiabetic efficacy of the isolated compound was evaluated in STZ-induced diabetic rats at the dose of 5 mg/kg b.w. for duration of 21 days. The present study reports a new flavocnoid compound isolated from the methanolic extract of T. angustifolia leaves and identified as 8-hydroxyapigenin 7-O-D-glucopyranoside. The flavonoid compound exhibited potent antidiabetic (hypoglicemic) activity in STZ-induced diabetic rats with promising antioxidant (radical scavenging activity) potential in vitro.