RESUMEN
The chemical investigation of the methanolic root extract of Flacourtia vogelii led to the isolation of a new arylbenzoate derivative, vogelinal (1), together with thirteen known compounds (2-14). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. All the compounds were tested for their antioxidant, antifungal and antibacterial activities. Compound 7 exhibited the highest antioxidant potential, with RSa50of 11.80 ± 2.13 µg/mL, RSa50of 42.60 ± 6.32 µg/mL and RC50 of 51.60 ± 7.71 µg/mL for the DPPH, ABTS and FRAP assay, respectively. Compound 13 displayed weak antifungal effect with MIC value of 125 µg/mL against Candida parapsilosis. Compound 8 showed weak antibacterial effect with MIC value of 125 µg/mL, against Shigella dysenteria. The present study, conclude that this species could be a promising source of antioxidant and antibacterial constituents.
Asunto(s)
Flacourtia , Salicaceae , Antioxidantes/química , Antifúngicos/farmacología , Antifúngicos/química , Salicaceae/química , Antibacterianos/química , Extractos Vegetales/farmacología , Extractos Vegetales/químicaRESUMEN
Three new prenylated furoquinoline alkaloids named lecomtequinoline A (1), B (2), and C (3), together with the known compounds anhydroevoxine (4), evoxine (5), dictamnine (6), N-methylflindersine (7), evoxanthine (8), hesperidin, lupeol, ß-sitosterol, stigmasterol, ß-sitosterol-3-O-ß-d-glucopyranoside, stearic acid, and myristyl alcohol, were isolated by bioassay-guided fractionation of the methanolic extracts of leaves and stem of Vepris lecomteana. The structures of compounds were determined by spectroscopic methods (NMR, MS, UV, and IR) and by comparison with previously reported data. Crude extracts of leaves and stem displayed high antimicrobial activity, with Minimum Inhibitory Concentration (MIC) (values of 10.1-16.5 and 10.2-20.5 µg/mL, respectively, against Escherichia coli, Bacillus subtilis, Pseudomonas agarici, Micrococcus luteus, and Staphylococcus warneri, while compounds 1-6 showed values ranging from 11.1 to 18.7 µg/mL or were inactive, suggesting synergistic effect. The extracts may find application in crude drug preparations in Western Africa where Vepris lecomteana is endemic, subject to negative toxicity results in vivo.
Asunto(s)
Alcaloides/aislamiento & purificación , Antibacterianos/aislamiento & purificación , Quinolinas/aislamiento & purificación , Rutaceae/química , Alcaloides/química , Antibacterianos/química , Bacillus subtilis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Micrococcus luteus/efectos de los fármacos , Estructura Molecular , Extractos Vegetales/química , Hojas de la Planta/química , Tallos de la Planta/química , Quinolinas/química , Staphylococcaceae/efectos de los fármacosRESUMEN
Bioassay-guided fractionation of the methanol extract of the stem bark of Klainedoxa gabonensis Pierre ex Engl. (Irvingiaceae) afforded 12 compounds, namely, ellagic acid (1), ellagic acid 3,3'-dimethylether (2), gallic acid (3), methyl gallate (4), lupeol (5), ß-amyrin (7), erythrodiol (8), oleanolic acid (9), betulinic acid (6), hederagenin (10), bayogenin acid (11), and stigmasterol-3-O-ß-d-glucopyranoside (12). Compounds 1-3 and 7-12 were isolated for the first time from this genus. The structures were established on the basis of 1D/2D NMR experiments and mass spectrometric data. Crude extract, fractions (A, B, C and D) and pure compounds were tested for their antimicrobial activity using paper disk agar diffusion assay. The test delivered a range of low to high activities for phenolic compounds 1-4, low or missing activities for terpenoid compounds 5-11, and impressive very high antibacterial/antifungal values for two fractions C and D probably due to synergistic effects of compounds. The broth microdilution assay revealed MICs of 15.4-115.1 µg/mL for phenolic compounds, MICs higher than 1 mg/mL for terpenoids and MICs of 4.5-30.3 µg/mL for fractions C and D. The determination of the radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay gave high antioxidant values for the methanol extract and fraction D (IC(50) 10.45 and 5.50 µg/mL) as well as for the phenolic compounds 1-4 (IC(50) 45.50-48.25 mM) compared to the standard 3-t-butyl-4-hydroxyanisole (BHA) (IC(50) 44.20 mM).
Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , Streptophyta/química , Antibacterianos/química , Antibacterianos/farmacología , Antiinfecciosos/química , Antifúngicos/química , Antifúngicos/farmacología , Antioxidantes/química , Compuestos de Bifenilo/química , Pruebas de Sensibilidad Microbiana , Fenoles/química , Picratos/química , Extractos Vegetales/química , Raíces de Plantas/químicaRESUMEN
The study of the chemical constituents of the stem bark of Teclea afzelii (Rutaceae) has resulted in the isolation and characterization of four furoquinoline alkaloids, namely kokusaginine (1), tecleaverdoornine (2), maculine (3) and montrifoline (4) together with lupeol (5) and beta-sitosterol glucopyranoside (6). The structures of the isolated compounds were elucidated based on spectroscopic studies. The antimalarial activity of compounds 1-4 against Plasmodium falciparum in vitro shows partial suppression of parasitic growth.