Unraveling the Antidiabetic Effect of Alternantera brasiliana(L.) Kuntze: A Combined in Vitroand in VivoApproach

Background of the study This study established the antidiabetic efficacy of Alternantera brasiliana in vitroand in vivo, identified the most active fraction and profiled the chemical constituents of the most active fraction.Methodology The leaf of A. brasilianawas air-dried, pulverized and extracted with methanol and evaluated for its α-amylase activity at different concentrations using in vitromethod. The in vivoantidiabetic activity of the extract and glibenclamide was evaluated in glucose loaded and streptozotocin-induced diabetic rats using various doses, while the most active partitioned fraction was identified using glucose loaded method followed by identification of its chemical constituents through GC-MS analysis.Results The extract elicited good α-amylase inhibitory potential with IC50 = 0.45 mg/mL. Also, the 50 mg/kg dose demonstrated the highest percentage blood glucose level reduction and significantly (P> 0.05) comparable to glibenclamide (5 mg/kg) from 0.5 to 4 h. The streptozotocin-induced antidiabetic assay showed that the 50 mg/kg demonstrated better activity than glibenclamide (5 mg/kg) and was significantly comparable on days 10 and 14. The aqueous methanol fraction was the most active fraction with 53% blood glucose level reduction at 4 h. The secondary metabolite profiling identified 30 chemical compounds whereby 1H-Indole-2-carboxylic acid, 6-(4-ethoxyphenyl)-3-methyl-4-oxo-4,5,6,7-tetrahydro-, isopropyl ester, Benzo[h]quinoline, 2,4-dimethyl-, thymol and 13,5-trioxane as the major constituents.Conclusion The antidiabetic activity demonstrated by the A. brasilianaextract established its antidiabetic efficacy