Preliminary Phytochemical Investigation, HPTLC Standardization and in-vitro Antidiabetic Activity of Stachytarpheta Urticifolia Leaf Ethanolic Extract

Abstract

Diabetes mellitus is a chronic metabolic disorder characterized by persistent hyperglycemia resulting from defects in insulin secretion, insulin action, or both. Despite the availability of several synthetic anti-diabetic agents, their long-term use is often associated with adverse effects and limitations, necessitating the search formsafer and effective alternatives from natural sources. The present study was undertaken to evaluate the in vitro anti-diabetic potential of the ethanol extract of Stachytarpheta urticifolia leaves (EESU) by enzyme inhibition studies. Fresh leaves of Stachytarpheta urticifolia were collected, authenticated, dried, powdered, and successively extracted using petroleum ether, benzene, chloroform, ethanol, and water. Preliminary phytochemical screening was carried out using standard qualitative methods. Total phenolic content was estimated using the Folin–Ciocalteu reagent method, and HPTLC fingerprinting was performed for standardization of the ethanol extract using quercetin as the reference standard. The in vitro antidiabetic activity of EESU was evaluated by assessing α-amylase and α-glucosidase inhibitory activities at different concentrations, with acarbose used as the standard drug. Phytochemical screening revealed the presence of alkaloids, flavonoids, glycosides, tannins, polyphenols, saponins, triterpenoids, and amino acids in the ethanol extract. Among all extracts, the ethanol extract showed the highest percentage yield (26.63% w/w) and the highest total phenolic content (254.66 ±19.55). HPTLC analysis confirmed the presence of quercetin in the ethanol extract. EESU exhibited concentration-dependent inhibition of both α-amylase and αglucosidase enzymes, with IC₅₀ values of 269.88 µg/mL and 351.38 µg/mL, respectively, compared to acarbose with IC₅₀ values of 27.49 µg/mL and 25.07 µg/mL. The findings of the present study suggest that the ethanol extract of Stachytarpheta urticifolia leaves possesses promising in vitro anti-diabetic activity, which may be attributed to its rich phytochemical composition, particularly phenolic compounds and flavonoids such as quercetin. Further in vivo and mechanistic studies are warranted to validate its therapeutic potential as a natural anti-diabetic agent.