Combretaceae - silver cluster-leaf, silver terminalia
Deciduous tree, endemic to the southern Africa; bark reddish brown, peels away in strips; leaves crowded at the ends of branches, narrowly obovate-elliptic, blue-green above, paler below, densely covered in silvery hairs; flowers in axillary spikes, pale yellow to creamy white; fruit an oval nut, surrounded by a flat wing.
„In traditional medicine, both leaves and roots have been used as a remedy for stomach ailments and a concoction of the roots for treating bilharzia, diarrhoea and pneumonia. The bark is used against diabetes and to dress wounds.“ https://en.wikipedia.org/wiki/Terminalia_sericea
„Terminalia sericea Burch. Ex. DC (Combretaceae) extracts are used to treat bacterial infections, diarrhea, and diabetes. Intermediate and polar extracts of the roots exhibited antibacterial activity against Staphylococcus aureus, Escherichia coli, Bacillus anthracis, and Pseudomonas aeruginosa, while the petroleum ether extract was inactive. The extracts were mildly active against Bacillus anthracis and Pseudomonas aeruginosa but exhibited the highest activity against Staphylococcus aureus. They also exhibited antifungal activity against Candida albicans and Aspergillus niger. An 80% aqueous ethanol extract of the roots did not have any effect on blood glucose levels during an oral glucose tolerance test (OGTT), in mice (P > 0.05).“
[Some pharmacological properties of extracts of Terminalia sericea roots. Moshi, M. J., & Mbwambo, Z. H., Journal of ethnopharmacology, Vol.97(1), 2005, 43-47]
„Bioassay-guided fractionation of an acetone extract of T. sericea stem bark led to the isolation of four known compounds namely β-sitosterol (1), β-sitosterol-3-acetate (2), lupeol (3), and stigma-4-ene-3-one (4), in addition to two inseparable sets of mixtures of isomers [epicatechin-catechin; (M1) and gallocatechin-epigallocatechin; (M2). 1 and 3 showed best inhibitory activity on α-glucosidase (IC50:54.5 μM and 66.48). The bio-evaluation of purified compound’s inhibitory activity on α-amylase, showed that lupeol and β-sitosterol exhibited IC50 values of 140.72 and 216.02 μM respectively against α-amylase. 2, M1, 3 and M2 were found to be non-toxic to Vero cells. This study is the first to report a-glucosidase, a-amylase of M1, M2, 2 and 4 isolated from T. sericea which validated the traditional use of the bark of T. sericea for diabetes in South Africa.“
[Nkobole, N., Houghton, P. J., Hussein, A. A., & Lall, N. (2011). Antidiabetic activity of Terminalia sericea Burch. Ex DC constituents.]