Entada africana is a West African tree with numerous ethnomedicinal uses. The bark and root of E.
africana have been investigated for their phytochemical compositions. However,
knowledge on phenolic composition of the leaves, which are predominantly used
in the Republic of Benin for the treatment of wounds, fractures and sprains, and their
bioactivity is still
scarce. This study aims at elucidating phenolic compounds of a hydroalcoholic
leaf extract of E. africana and assessing their bioactivity. Structural elucidation was performed using
HRESI-MS and NMR methods. Bioactivity of E. africana crude extract, fractions thereof, and isolated compounds was evaluated using TNF-α
stimulated human keratinocytes (HaCaT) as an in
vitro model of skin inflammation. As a result, 11 phenolic compounds were identified
in the hydroalcoholic leaf extract of E. africana, which moderately inhibited IL-8
release to 48.1 ± 3.5%
with an IC50 = 59.2 µg/mL. Among the 11 phenolic compounds, 3′,4′,7-trihydroxyflavone showed a
significant inhibitory effect on IL-6 interleukin with a maximum inhibition of
74.4 ± 2% and IC50 = 17.8 µg/mL and moderately reduced IL-8 interleukin secretion to 40.2 ± 5.1% with
IC50 = 126.2 µg/mL. This study provides for the first time an
overview of the phenolic compounds present in the hydroethanolic leaf extract
of E. africana and their anti-inflammatory potential, which support its traditional medicinal use
in the
treatment of wounds, fractures and sprains.
The authors declare that there is no conflict of interest.
