Bioactive Caffeic Glycoside Ester and Antimicrobial Activity of Various Extracts from the Leaf of Stachytarpheta angustifolia Mill Vahl (Verbenaceae).

Abstract

This study examines the extraction and isolation of the Caffeic glycoside ester Compound 1. [mp 222-224 0C], C29H26O15, [M]+624.594 (EIMS) from the n-BuoH soluble fraction of the ethanolic extract of S. angustifolia (verbenaceae). It was characterized on the basis of spectral analysis (UV, FTIR, 1and 2D NMR techniques) as –I²-(31, 41- dihydroxyphenyl) -ethyl-O-I±-L- rhamnopyranosyl- (1-3)-I²-D- (4-O-Caffeoyl) -glucopyranoside. Antimicrobial properties of Compound 1 and other extracts were tested against some microorganisms namely Staphylococcus aureus, Streptococcus pyogenes, Proteus vulgari,Pseudomonas aeruginosa, Klebsiella pneumoniaer, Escherichia coli, Salmonella typhi Bacillus subtilis, Penicillium digitatum, Candida albicans, Aspergillus niger, Fusarium oxysorum and Penicillium nototum. The antimicrobial sensitivity test indicated that the extract inhibited the growth of Staphylococcus aureus, Streptococcus pyogenes Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi, Penicillium digitatum, Candida albicans and Penicillium nototum with 30mm, 29mm, 35mm, 34mm, 36mm, 28mm, 24mm, 25mmwhile the highest activity of caffeic glycoside ester was exhibited by the n-BuoH fraction against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Salmonella typhi with 34mm, 36mm and 36mm respectively.