<i>In-Vitro</i> Study of the Anti-Diabetic Property of Ethanol Leaves Extract of <i>Clerodendrum splendens</i> G. Don Verbenaceae

Abstract

Aim The aim of this study was to evaluate the in vitro antidiabetic activity of Clerodendrum splendens and to identify its bioactive constituents. Methods The plant was extracted with ethanol using the cold maceration method and the crude extract (CE) was partitioned in a separating funnel into n-hexane (HF), ethyl acetate and aqueous ethanol fractions. Phytochemical screening of CE was done following standard methods while HF which gave the best activity was further sub-fractioned using Vacuum Liquid Chromatography into final 5 sub-fractions as guided by analytical thin layer chromatography. The in-vitro alpha-amylase assay was done using standard procedure and concentrations of 1.0, 0.5, 0.25 and 0.125 mg/mL were prepared for all the groups including the standard drug, acarbose in triplicates. The process was repeated for the sub-fractions using 0.5, 0.25 and 0.125 mg/mL and the sub-fraction that gave the best activity, VHF-2 was analyzed using chromatography-mass spectrometry (GC-MS). Results The phytochemical analysis revealed the presence of glycosides, tannins, alkaloids steroids and terpenoids and flavonoids in CE. The results of the alpha-amylase assay revealed that HF produced the highest percentage inhibition of 63.97% and half-maximal inhibitory concentration (IC 50 ) of 0.49 mg/mL when compared with other fractions. The IC 50 of VHF-2 and the acarbose were 4.19 and 0.485 mg/mL respectively and GC-MS characterization revealed the presence of 14 major compounds. Conclusion The ethanol leaves extract of C. splendens holds potential antidiabetic agents which can be used in the management of diabetes mellitus.