New flavanone and other constituents from erythrina senegalensis A. DC. (fabaceae)

Abstract

The chemical investigation of the methanol trunk bark extract of Erythrina senegalensis led to the isolation of a new flavanone, 5,7,4’-trihydroxy-3’,5’-bis(3-methylbutadienyl)flavanone (trivially named senegalensisnone) (1), together with seven known compounds, abyssinone-V-4’-O-methyl ether (2), abyssinone V (3), Calopocarpin (4), genistein (5) mixture of stigmasterol (6) and β-sitosterol (7) and β-sitosterol-3-O-β-D-glucopyranoside (8). 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. The absolute configuration of 1 was deduced based on comparison of its experimental CD with that of similar compound. All the compounds were tested for their antibacterial, antifungal and antioxidant activities. Compound 4 displayed weak antibacterial activity against Salmonella enteritidis with MIC value of 62.5 μg/mL. All the isolates were found to be inactive as antioxidant agents in the DPPH, ABTS and FRAP assays.

Graphical Abstract

Keywords:

• Erythrina senegalensis
• fabaceae
• flavanone
• antibacterial activity
• antifungal activity
• antioxidant potential

Acknowledgments

The others acknowledge the laboratory of Chemistry of the University of Buea for its supports.

Authors’ contributions

Conceptualisation, A.T.T., J.L.D.B., A.N.W., J.M.L., F.A.A.T.; Formal analysis, A.T.T., E.N.T.; Methodology, A.T.T., J.M.L., F.M., E.G.G.B. F.A.A.T., J.Am; writing—original draft preparation, A.T.T. J.L.D.B; writing—review and editing, All the authors. All authors have read and agreed to the published version of the manuscript.

Data accessibility

The datasets supporting this article have been uploaded as part of the Electronic Supplementary Material.

Disclosure statement

The authors have no competing interests.

Figure 1. Structures of compounds 1–8 from the methanolic leaf extract of E. senegalensis.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.