Isolation and in vitro characterization of wound healing compounds from Combretum smeathmanii G.Don

Combretum smeathmanii G.Don (Combretaceae) (Fig.) is a scandent shrub widely used by traditional healers in Ghana and is indicated for the treatment of wounds, boils among other conditions. The aim of this project is to isolate and characterize secondary metabolites from this plant and to test their activity and function on skin cell lines.

Fractionation of an ethyl acetate extract soluble fraction of an ethanol-water extract of the leaves on Sephadex-LH20 and further isolation using preparative HPLC showed the presence of procyanidins as a major group of compound present. At present epicatechin, procyanidin B2 (epicatechin(4β→8)epicatechin), Procyanidin B5 (epicatechin(4β→6)epicatechin), procyanidin C1(epicatechin(4β→8)epicatechin(4β→8) epicatechin), procyanidin D1 (epicatechin(4β→8)epicatechin(4β→8)epicatechin)(4β→8)epicatechin) and hitherto unidentified oligomeric procyanidins have been isolated. All compounds were elucidated by means of spectroscopic analyses (ESI-MS, CD spectra, 1D- and 2D-NMR) and NMR Data was compared to literature as free phenols or peracetylated derivatives.

Biological studies of extracts and isolated compounds from this plant on HaCaT cell keratinocyte cell line indicated significant stimulation of cellular metabolic activity (MTT assay), affection of cellular proliferation (BrdU ELISA) and for some of the isolated compounds weak necrotic cell activity (LDH release) at higher concentration.

Fig. 1: Combretum smeathmanii G. Don. © Emelia Kisseih