Isolation and structure elucidation of compounds from Coccinia grandis leaves extract.

In this study, preliminary phytochemical screening of dried leaves of Coccinia grandis showed presence of triterpenoids, phenolics, flavonoids, saponins and sterols. As well as, five phenolic compounds namely; ferulic acid (1), methyl caffeate (2), ligstroside(3), trans-p- coumaric acid (4) and kaempferol-3-O-β-D-glucoside (5) were isolated from selected fraction of the methanol extract of Coccinia grandis leaves. The structures of the isolated compounds were identified using different NMR spectroscopic techniques (1H, 13C NMR, COSY, HSQC, HMBC) and mass spectrometry. Compounds (1), (2), (4) and (5) were isolated for the first time from Coccinia grandis species while compound (3) was isolated for the first time from Cucurbitaceae family. Moreover, the anti-microbial activity of the selected fraction of the methanol extract of Coccinia grandis leaves was tested against a panel of Gram-positive, Gram-negative bacteria and yeast. A considered activity was recorded against Bacillus cereus (inhibition zone of 20 mm with MIC 1mg/ml).