Isolation and antibacterial activity of anomanol B and other secondary metabolites from the stem bark of Anonidium mannii (Annonaceae)

• Published in: Natural product research Vol. 38; no. 11; pp. 1813 - 1822
• Main Authors: Ngangoue, Marcelle Oliviane, Ndifor, Ache Roland, Ambassa, Pantaleon, Guefack, Michel-Gael F., Kuete, Jenifer R. N., Chi, Godloves Fru, Ngameni, Bathelemy, Kuete, Victor, Ngadjui, Bonaventure Tchaleu
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 02.06.2024; Taylor & Francis Ltd
• Subjects: a phenanthridine-6(5H)-one alkaloid; Aerogenes; Annonaceae - chemistry; Anonidium mannii; Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; Antibacterial activity; Antibiotics; Bacteria; Chloramphenicol; Chloromycetin; Chromatography; Coliforms; E coli; Gram-negative bacteria; Gram-Negative Bacteria - drug effects; Klebsiella; lanostane-type triterpene; Metabolites; Microbial Sensitivity Tests; Minimum inhibitory concentration; Molecular Structure; Plant Bark - chemistry; Plant extracts; Plant Extracts - chemistry; Plant Extracts - pharmacology; Secondary metabolites; antibacterial activity; Anonidium mannii; lanostane-type triterpene; a phenanthridine-6(5H)-one alkaloid
• ISSN: 1478-6419; 1478-6427
• DOI: 10.1080/14786419.2023.2223728

A new Lanosta-7,9(11),22-trien-3,15,20-triol named Anomanol B 1, together with five known compounds: manniindole 2, arborinine 3, polycarpol 4, 8,9-dimethoxyphenanthridin-6(5H)-one 5 and 3-O-β-D-glucopyranosyl-β-sitosterol 6 were isolated from the stem bark extract of Anonidium mannii by routine chromatography techniques. 8,9-dimethoxyphenanthridin-6(5H)-one 5, was reported from natural origin for the first time. The structures of the compounds were established by comprehensive elucidation of spectroscopic data and by comparison with literature data. Evaluation of the isolates on Gram-negative bacteria such as Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Providencia stuartii, and Pseudomonas aeruginosa showed that, compound 1 had weak antibacterial activity with minimal inhibitory concentrations (MIC) varying from 128 to 256 µg/mL. Compounds 3, 5, and 6 exhibited moderate to weak activity with MIC of 32 to 128 µg/mL and 64 to 256 µg/mL compared to the reference drug chloramphenicol which inhibited the growth of all studied bacteria with MIC values of 16 to 64 µg/mL.