Investigation of the ethanol extract (EE) of Entada rheedii Spreng. (Fabaceae) seeds led to the isolation of four phenolics: protocatechuic acid C1, protocatechuic acid methyl ester C2, 1,3,4-trihydroxybenzene glucoside C3, phaseoloidin C4, three thioamides: entadamide A C5, entadamide A-β-D- glucopyranoside C6, entadamide C C7, and two saponins: rheedeioside A C8 and rheedeioside B C9. The structures of the isolated compounds were established on the basis of physicochemical properties and spectral analysis (1H, 13C-NMR, COSY, HSQC, and HMBC). The EE and certain isolated compounds evidenced potent antiulcerogenic, and antibacterial activities. Weak antiviral activity was also reported. Although this seeds is famous for its saponins, the potent antiulcerogenic activity was attributed to synergism between its saponins, thioamides, and phenolics. Its antimicrobial activity was due to its thioamides and phenolic content only. The observed pharmacological activities provide scientific validation of ethnomedicinal use of the seeds in treating gastric aliments and as antimicrobial.
Key words: rheedeioside A; entadamide A; phaseoloidin; gastric ulcer; antibacterial.
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