Isolation, Characterization and Antibacterial Activity Study of Bioactive Compounds from Leaves of Cyphostemma cyphopetalum

Abstract

Cyphostemma cyphopetalum is a herbaceous climber species within the Vitaceae family, found in various tropical and subtropical regions of Africa. It has a history of traditional use in Ethiopia for treating various health issues in humans and livestock, includ-ing snake bites, rabies, and eczema. Despite its reported ethnomedicinal uses, there is a lack of sufficient scientific literature regarding the isolation and characterization of its bioactive chem-ical compounds. The objective of this work was to isolate bioactive compounds from the leaves of Cyphostemma cyphopetalum, characterize their chemical structures using FTIR and NMR spec-troscopy, and evaluate their antimicrobial activities. Isolation was done using column chromatographic separation techniques. Spectro-scopic techniques, including Fourier transform infrared and nuclear magnetic resonance, were used for functional group identification and structural elucidation. Moreover, the paper disc dif-fusion bioassay method was used to evaluate the antibacterial activity of the isolated bioactive compounds. Three fractions were successfully isolated using chloroform with dichloromethane and chloroform with ethyl acetate as eluting solvents and silica gel as a stationary phase. After care-ful interpretation of the experimental results and comparison with the literature, the isolated fractions were constituted mainly by stigmasterol (fraction 1), β-sitosterol (fraction 2), and trans-resveratrol (fraction 3). The antibacterial activities of each isolated fraction were tested against Ralstonia solanacearum, a gram-negative bacterium, and Staphylococcus aureus, a gram-positive bacterial pathogen.Comparatively, the highest mean inhibitory value of 10.03 ± 0.13 mm was exhibited by fraction 2, which was followed by 6.25±0.05 mm inhibition activity recorded for fraction 1 against R. solanacearum, while fraction 3 did not exhibit any bacterial activity against both the strains. We have successfully isolated and characterized three compounds (1-3) from leaves of C. cyphopetalum and evaluated their antibacterial activity. A maximum mean inhibi-tory value of 10.03 ± 0.13 mm was exhibited by compound 2 against R. solanacearum.