Biological and phytochemical investigations on three plants widely used in Guinean traditional medicine.

摘要

Extracts of the bark of Pavetta owariensis (Rubiaceae) were found to exhibit schistosomicidal, molluscicidal, antiviral and antibacterial activities. Bio-assay guided fractionation resulted in the isolation of new antimicrobially active proanthocyanidins with doubly-linked structures. In a chemical investigation on the stem-bark, 3 flavan-3-ol, 4 procyanidin-A-type, 6 trimeric procyanidins, 4 tetrameric procyanidins, 1 pentameric procyanidin (all possessing doubly-linked structures), 15 fatty acids, 19 fatty alcohols, 11 fatty esters, 8 alkanes, 4 sterols, 7 ketosteroids, 5 quinic acid esters, and 5 ferulic esters were characterized.; The crude alkaloids from the aerial parts of Borreria verticillata (Rubiaceae) has shown to exhibit antibacterial and cytotoxicity properties. Bio-assay guided fractionation led to the isolation of three antibacterial active bis-indole alkaloids, along with 5 other alkaloids.; Extracts of Harrisonia abyssinica (Simaroubaceae) were found to exhibit molluscicidal, antibacterial, antiviral and antifungal properties. Bio-assay guided fractionation resulted in the isolation of the active components which are under current investigation. Chemical investigations on the stem-bark and the root led to the isolation of 2 sterols, 3 ketosteroids, 2 chromones, 3 limonoids.; The schistosomicidal effect of Pavetta owarienis along with the molluscicidal potency of Harrisonia abyssinica may be considered as a possible alternative in a schistosomiasis control program in affected areas such as the South part of Guinea-Conakry, where these plants are available.