Chemical profiling by UHPLC-Q-TOF-HRESI-MS/MS and antibacterial properties of Entada abyssinica (Fabaceae) constituents.

A rapid untargeted UHPLC-Q-TOF-ESI-MS/MS-Based metabolomic profiling of the medicinal plant Entada abyssinica was performed. A total of 18 metabolites were detected, of which 10 could not be identified. Based on this result, an extensive chemical investigation of the CH2Cl2-MeOH (1:1) extract of this plant was carried out, leading to the isolation of a new ceramide, named entadamide (1), together with nine known compounds: monomethyl kolavate (2), 24-hydroxytormentic acid (3) chondrillasterol (4), 3-O-ß-D glucopyranosylstigmasterol (5), 3-O-ß-D glucopyranosylsitosterol (6), quercetin 3'-methylether (7), 2,3-dihydroxypropyl icosanoate (8), 2,3-dihydroxy-propyl 23-hydroxytricosanoate (9) and 2,3-dihydroxy-propyl 24-hydroxytetracosanoate (10). Their structures were elucidated by the analyses of their spectroscopic and spectrometric data (1D and 2D NMR, and HRESI-MS) in comparison with those reported in the literature. Furthermore, the crude extract and some isolated compounds were tested against non-ciprofloxacin resistant strains viz, Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Samonella thyphi (ATCC 19430) and Samonella enterica (NR4294). The tested samples demonstrated significant activity against all the tested bacteria (MIC values: 3.12-12.5 µg/mL).

Antimicrobial indole alkaloids from Tabernaemontana corymbosa.

Four unreported monoterpene indole alkaloids, tabernaecorymines B-E (1-4), together with twenty-one known indole alkaloids (5-25) were obtained from the stem bark of Tabernaemontana corymbosa. Their structures and absolute configurations were elucidated by extensive spectroscopy, quantum chemical calculations, DP4+ probability analyses and Mo2(OAc)4-induced electronic circular dichroism experiment. The antibacterial and antifungal activities of these compounds were evaluated and some of them showed significant activity against Staphylococcus aureus,Bacillus subtilis, Streptococcus dysgalactiae and Candida albicans.

Antifungal and antioxidant activity of Crassocephalum bauchiense (Hutch.) Milne-Redh ethyl acetate extract and fractions (Asteraceae).

BACKGROUND: Crassocephalum bauchiense is a flowering plant, found in the West Region of Cameroon. Previous studied has highlighted the antibacterial and the dermal toxicological safety as well as the immunomodulatory activities of the ethyl acetate extract of its dry leaves. As an extension of the previous researches, the current work has been undertaken to evaluate the in vitro antifungal and antioxidant activities of C. bauchiense dried leaves ethyl acetate extract and fractions. METHODS: The extract was obtained by maceration in ethyl acetate and further fractionated into six fractions labeled F1 to F6 by flash chromatography. The antifungal activity of the extract and fractions against yeasts and dermatophytes was evaluated using broth microdilution method. Antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO) and ß-carotene - linoleic acid assays. RESULTS: The extract (MIC = 0.125 - 4 mg/ml) was found to be more active on dermatophytes and yeasts compared to the fractions. The ethyl acetate extract and fractions exhibited strong scavenging activity on DPPH (CI50 = 28.57 - 389.38 µg/ml). The fractions F3 and F6 expressed best antioxidant activity on DPPH radicals compared to the crude extract. CONCLUSION: The results of these findings clearly showed that C. bauchiense ethyl acetate extract has a significant antifungal and antioxidant activity. It is therefore a source of active compounds that might be used as antifungal and antioxidant agents.