Pterocarpus osun, or African padauk is a plant belonging to the Dalbergieae tribe of Papilionaceae subfamily. It is also called camwood, black camwood, bloodwood, Akwara in Igbo, Osun dudu, Gbingbin in Yoruba, Ukme in Edo, Lagos camwood. However, it should not be confused with the true camwood (Baphia nitida)
Pterocarpus osun is an evergreen or deciduous plant that grows mostly in the lowland evergreen and semi-deciduous forests of Nigeria, Cameroon, and Equatorial Guinea. It can grow up to 30 m height or smaller. Leaves are alternate, imparipinnately compound with many leaflets. Leaflets are alternate to almost opposite, oblong to ovate, papery, densely hairy below when young but later glabrescent.
The fruits, which are indehiscent pods, are brownish-orange, almost globose, and slightly pointed at the apex. It contains 4 to 5 dark brown, kidney-shaped, hard and shiny seeds embedded in the reddish pulp.
In traditional medicine, the powdered stem extract is used to treat rheumatism, eczema, gonorrhea, candidasis, acne, infection of the umbilical cord. The stem bark extract is used for treating dysentery, diarrhea, and gastrointestinal problems (Burkill, 1995).
Composition
Pterocarpus osun leaf contains phenol, saponins, tannins, cardiac glycosides, sterols, and terpenes. The heartwood contains red pigments of the santarubin and santalin groups, and can be used in histology stains (Osuagwu, 2008). Seed oil contains β-carotene, and hence vitamin A. It also has fatty acids such as linoleic acid, oleic acid, palmitic acid and behenic acid.
The stem bark and leaf extract contains high fiber, protein, ash, and lipids. The mineral composition includes phosphorus, calcium, magnesium, potassium, sodium, cobalt, zinc, nickel, chromium, sulphur, and nitrogen.
Medicinal Benefits of African padauk (Pterocarpus osun)
Sickle Cell Disease Management:
Pterocarpus osun is one of the herbs in the Niprisan or Nicosan, herbal medicine developed by Nigerian National Institute for Pharmaceutical Research and Development (NIPRD) for the management of sickle cell crisis.
The herbal combination in the phytomedicine includes pepper seeds [Piper guineense], clove flower buds [Eugenia caryophyllata], caprium stem [Pterocarpus osun], sorghum leaves [Sorghum bicolor], and “trona”. Though the drug improved the symptoms of the disease, it did not effectively control the complication or anemia. The drug production has since stopped due to financial issues.
Antimicrobial activity:
The stem bark extract of Pterocarpus osun inhibits bacteria such as Enterobacter aerogenes, Alcaligenes faecalis, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus (Manjunatha, 2006).
Antioxidant property:
The stem extract exhibit antioxidant property. The seed of the plant contains lecithin, which scavenge free radical and inhibit lipid peroxidation.
In a study by Taofeek O. Ajiboye et al., the leaf extracts of the plant improved the altered levels of liver and serum enzymes in the acetaminophen-induced redox imbalance in Wistar rat liver. It also improved antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase.
Cosmetic Use:
The dried leaf is used in producing traditional black soap, alongside the ash of burnt cocoa pods and palm oil. The paste from the heartwood, bark, and roots are also applied to the skin. The stem extract has depigmenting property, and can be used instead of synthetic cosmetic formulations.
References
- https://pubmed.ncbi.nlm.nih.gov/22435571/#:~:text=Niprisan%C2%AE%20is%20an%20herbal,%5BPterocarpus%20osun%20(L.)
- https://www.researchgate.net/publication/361616564_Nutrients_Phytochemical_Antioxidant_and_Antimicrobial_Analysis_of_Pterocarpus_osun_Stem_Bark_and_Leaf_for_Their_Nutritional_Medicinal_Capacity
- https://forestcenter.iita.org/index.php/2019/07/23/pterocarpus-osun-craib/
- https://uses.plantnet-project.org/en/Pterocarpus_osun_(PROTA)
- https://www.tandfonline.com/doi/abs/10.3109/01480540903170746?journalCode=idct20
