Cylicodiscus gabonensis

Cylicodiscus gabonensis

Cylicodiscus gabunensis

Common Names: Denya, Okan, African Greenheart
Local Names: Cameroon: Olosan (Baka), Aja-igi (Yoruba) | Gabon: Bokoka (Fang) | Nigeria: Edum (Edo), Mkpukpa-ana (Igbo)
Species ID: NMP-034 |
wfo-0000174888 | NCBI_Taxonomy ID: 204972

Scientific Classification

Kingdom: Plantae

Clade: Tracheophytes

Clade: Angiosperms

Clade: Eudicots

Order: Fabales

Family: Fabaceae

Genus: Cylicodiscus

Species: C. gabunensis

Binomial Name: Cylicodiscus gabunensis Harms

Synonyms: Cyrtoxiphus staudtii Harms, Erythrophleum gabunense Taub., Erythrophleum letestui A.Chev. ex Baker f., Piptadenia gabunensis (Harms) Roberty

Morphological Description

Cylicodiscus gabunensis is a large, evergreen or deciduous tree, reaching 30–60 m in height, with a straight, cylindrical bole up to 2 m in diameter, often swollen or fluted at the base. Key features include:

·       Bark: Rough, scaly, grey-brown, exuding red resin when cut

·       Leaves: Pinnate, compound, 10–20 cm long, with 10–20 pairs of elliptical leaflets, 2–4 cm long, glossy green

·       Flowers: Small, white, 3–5 mm, in axillary panicles, blooming seasonally

·       Fruit: Flat, woody pods, 10–20 cm long, 3–5 cm wide, brown, containing 4–8 flat seeds

Young trees bear brown thorns, which diminish with age (Fern, 2022).

Distribution and Habitat

Cylicodiscus gabunensis is native to West and Central Africa, including Gabon, Cameroon, Nigeria, Democratic Republic of Congo, and Ghana. It thrives in:

·       Regions: Lowland rainforests, riverine forests

·       Climate: Tropical, humid, 25–35°C, rainfall 1,500–3,000 mm annually

·       Soil: Well-drained, loamy, slightly acidic (pH 5.0–6.5)

·       Elevation: Sea level to 700 m

It prefers dense forest understories.

Ethnopharmacology

Cylicodiscus gabunensis is utilized in traditional African medicine, with studies supporting its applications:

·       Antimicrobial: Bark decoctions in Nigeria treat infections; ethanol extracts inhibit the growth of 17 microorgnisms. The best MIC and MBC values for the microorganisms sensitive to the extract were 0.00078 and 0.00315 mg/ml respectively. The greater and remarkable antimicrobial activity of the Ethyl acetate  extract of C. gabunensis  was recorded with Staphylococcus aureus, Proteus vulgaris and Bacillus cereus T. These results provide a rationalization for the traditional use of this plant for the treatment of infectious diseases (Kouam, J et al., 2007).

·       Anti-inflammatory: Leaf poultices reduce swelling.

·       Antimalarial: The antimalarial activity of ethanolic stembark extract of Cylicodiscus gabunensis was studied in vivo in mice infected with Plasmodium berghei berghei The stembark extract possesses a promising antiplasmodial activity, which can be exploited in malaria therapy (Okokon, J. E et al., 2006). The antimalarial activity of ethanolic extracts of C. gabunensis bark was confirmed in vitro, with evidence for phenolic acids, primarily gallic acid and close analogues such as ethyl gallate, likely providing this effect. Further fractionation produced the most potent fraction with a 50% inhibitory concentration of 4.7 µg/ml. These results support the use of the bark of C. gabunensis as a traditional medicine in the treatment of human malaria (Omar Aldulaimi et al., 2006)

·     Analgesic: The EACg was administered by oral route at the doses of 100, 200, and 400mg/kg. All the doses, were efficient on pain, with a more potent effect at 200 mg/kg (P<0.01) expressing 61.55% of inhibition in the acetic acid test or 63.11 and 87.09 % respectively during the first and the second phase in the formalin test. For the pain induced by thermal stimuli, the plant at 200 mg/kg expressed 73.09% of inhibition during the first hour in the hot plate test and 70.40% in the tail immersion test during the fourth hour. The effect of EACg (200mg/kg) was partially reversed by naloxone (1 mg/kg) in all the analgesic tests. For inflammation, the oedema volume at all the doses, was significantly reduced with 68.21 %; or 87.09 %; and 87.09 % respectively in the carrageenan, serotonin and histamine tests (one hour post dosing) at the dose of 200mg/kg(P<0.01). These results suggest that the EACg may have components that interact with opioid receptors, or serotonin and histamine pathways (Keugni, B. A. et al., 2014).

·       Gastrointestinal Aid: Bark in Ghana for stomach issues; tannins linked to astringent effects (Burkill, 1995).

Phytochemistry

Bioactivity is attributed to key compounds:

·       Phenolics: Gallic acid, catechins—antimicrobial, antimalarial

·       Tannins: Astringent, anti-inflammatory

·       Flavonoids: Antioxidant, analgesic

·       Saponins: Potential antimicrobial activity

·       Resins: Wound healing, from bark exudate

⚠  Toxicity Profile: No acute toxicity reported; LD₅₀ > 2,000 mg/kg in rats (safe at low doses). Excessive bark resin may irritate skin/mucous membranes due to tannins. Limited data on pregnancy use.

Additional Uses

·       Timber: Durable hardwood (Janka 2,700 lbf), termite-resistant, used for construction, flooring, furniture

·       Soap: Bark ash in Cameroon for saponin-based soap

·       Cultural: Wood in Gabon for carvings; bark in rituals

·       Conservation: Vulnerable due to logging; sustainable practices urged


References

  • Aldulaimi, O., Uche, F. I., Hameed, H., Mbye, H., Ullah, I., Drijfhout, F., ... & Li, W. W. (2017). A characterization of the antimalarial activity of the bark of Cylicodiscus gabunensis Harms. Journal of ethnopharmacology, 198, 221-225.
  • Okokon, J. E., Ita, B. N., & Udokpoh, A. E. (2006). Antiplasmodial activity of Cylicodiscus gabunensis. Journal of Ethnopharmacology, 107(2), 175-178.
  • Keugni, B. A., Longo, F., Fotio, L. A., Fogue, S. K., Dimo, T., & Etoundi, L. S. (2014). Analgesic and anti-inflammatory properties of the ethyl acetate extract of Cylicodiscus gabunensis (Mimosaceae) in rodents.
  • Kouam, J., Penlap, B. V., Ngadjui, B. T., Fomum, Z. T., & Etoa, F. X. (2007). Evaluation of antimicrobial activity of the stem bark of Cylicodiscus gabunensis (Mimosaceae). African Journal of Traditional, Complementary and Alternative Medicines, 4(1), 87-93.
  • Burkill, H. M. (1995). The Useful Plants of West Tropical Africa (2nd ed., Vol. 3, pp. 245–246). Royal Botanic Gardens, Kew.
  • Fern, K. (2022). Cylicodiscus gabunensis. Tropical Plants Database. Retrieved from https://tropical.theferns.info/viewtropical.php?id=Cylicodiscus+gabunensis

External Links

More Pictures

Compounds of Cylicodiscus gabonensis
References

Aldulaimi, O., Drijfhout, F., Uche, F. I., Horrocks, P., & Li, W. W. (2019). Discovery, synthesis and antibacterial evaluation of phenolic compounds from Cylicodiscus gabunensis. BMC complementary and alternative medicine, 19, 1-11.