Strychnos innocua

Strychnos innocua

Strychnos innocua

Common Names: Powder-bark monkey-orange, Green monkey-orange
Local Names: Kokiyar Biri, Namijin Kokiya (Hausa, Nigeria)
Species ID: NMP-253 |
wfo-0000502968 | NCBI_Taxonomy ID: 1040890

Scientific Classification

Kingdom: Plantae

Clade: Tracheophytes

Clade: Angiosperms

Clade: Eudicots

Clade: Asterids

Order: Gentianales

Family: Loganiaceae

Genus: Strychnos

Species: S. innocua

Synonyms: Strychnos alnifolia Baker, Strychnos dschurica (Gilg) A.Chev., Strychnos huillensis Gilg & Busse, Strychnos penduliflora Baker, Strychnos unguacha A.Rich.

Morphological Description

Strychnos innocua is a deciduous shrub or small tree, typically 2–12 meters tall, occasionally reaching 18 meters, with a low-branching bole 7–40 cm in diameter. Its key characteristics include:

·       Bark: Grey to grey-brown, smooth with a powdery surface that rubs off easily; used medicinally for its bioactive compounds (Burkill, 1985).

·       Leaves: Simple, elliptic to obovate (4–10 cm × 2–5 cm), dull green, with pale net-veining; petioles short (2–5 mm) (Fern, 2024).

·       Flowers: Small, greenish-yellow to cream (5–7 mm), in 2- or 4-flowered axillary clusters; fragrant, blooming seasonally (Prance & Jongkind, 2015).

·       Fruit: Spherical berries (4–7.5 cm diameter), bluish-green turning yellow, with a hard, woody skin; pulp sweet-sour, yellowish, slimy, containing many seeds (Kew Science, n.d.).

Distribution and Habitat

Strychnos innocua is widely distributed across tropical Africa, thriving in diverse ecological niches:

·       Geographic Range: Native from Côte d'Ivoire to Ethiopia, south to Angola, Zimbabwe, Mozambique, and Madagascar; common Ascin Nigeria’s savanna and woodlands (Kew Science, n.d.).

·       Habitat: Found in deciduous woodlands, open woodlands, rocky hills, and riverine areas; prefers well-drained, sandy or loamy soils (pH 5.5–7.0) with annual rainfall of 600–1,500 mm; occurs from sea level to 1,600 m (Fern, 2024).

·       Ecological Role: Contributes to savanna biodiversity; fruits are consumed by birds and mammals, aiding seed dispersal; supports pollinators like bees (Burkill, 1985).

Ethnopharmacology

Strychnos innocua is extensively used in West African traditional medicine, with pharmacological studies validating several applications (Uttu et al., 2022):

·       Antibacterial: In Nigeria, root bark treats gonorrhea. Ethyl acetate root bark extracts isolated campesterol and β-sitosterol, showing binding affinities of −7.8 and −7.9 kcal/mol against Staphylococcus aureus and Pseudomonas aeruginosa, respectively, suggesting antibacterial potential (Uttu et al., 2022).

·       Antivenom: In Nigeria, root infusions treat snake bites. Ethnopharmacological surveys confirm its use, though specific studies on antivenom activity are limited (Uttu et al., 2022).

·       Antidiabetic Potential: In Cameroon, leaf decoctions are used for diabetes. While direct studies on S. innocua are scarce, phytosterols like β-sitosterol suggest antidiabetic properties, as seen in related Strychnos species (Uttu et al., 2022).

·       Antioxidant: In Ghana, fruit extracts combat oxidative stress. The fruit pulp contains phenolic compounds, though specific antioxidant studies on S. innocua are limited compared to Strychnos spinosa (Omotayo & Aremu, 2021).

·       Nutritional and Tonic: In Nigeria, ripe fruit pulp is consumed as a tonic. The pulp is rich in carbohydrates and micronutrients, supporting its use for general health, though excessive intake may cause stomach upset due to trace alkaloids (Fern, 2024).

⚠  Toxicity Profile: Strychnos innocua is generally safe for moderate consumption of ripe fruit pulp, but other parts pose risks. The seeds and bark may contain toxic alkaloids like strychnine and brucine, though levels are lower than in species like Strychnos nux-vomica. Excessive fruit pulp consumption can cause gastrointestinal distress due to trace alkaloids. Ethanolic leaf extracts were non-toxic to Artemia salina (LC50: 162.10 µg/ml), but chronic use of bark or seed extracts may elevate liver enzymes (ALT increased by 10% after 30 days). Use is contraindicated in pregnancy and for children due to insufficient safety data. Potential heavy metal contamination in wild-harvested plants requires caution (Neuwinger, 1996; Omotayo & Aremu, 2021).

Phytochemistry

The bioactivity of Strychnos innocua is attributed to its phytochemical profile, though less studied than other Strychnos species (Uttu et al., 2022):

·       Phytosterols: Campesterol, β-sitosterol, isolated from root bark, with antibacterial and potential antidiabetic effects (Uttu et al., 2022).

·       Alkaloids: Trace amounts of strychnine and brucine in seeds and bark, contributing to toxicity but minimal in fruit pulp (Neuwinger, 1996).

·       Phenolics: Gallic acid, chlorogenic acid, present in fruit pulp, supporting antioxidant activity (Omotayo & Aremu, 2021).

·       Tannins: Found in bark, providing astringent properties for wound healing (Burkill, 1985).

·       Saponins: Trace amounts in leaves, potentially aiding antimicrobial effects (Fern, 2024).

Additional Uses

·       Culinary: Ripe fruit pulp is eaten raw or juiced in Nigeria; leaves are cooked as a vegetable in West Africa (Fern, 2024).

·       Timber: Wood is used in Nigeria for construction and tool handles due to its durability (Burkill, 1985).

·       Cultural: In Hausa culture, fruit pulp is used in rituals for health and vitality (Burkill, 1985).

·       Ecological: Planted in agroforestry to stabilize soils; fruits support wildlife, enhancing savanna ecosystems (Fern, 2024).

References

  • Adjanohoun, E. J., Ahyi, M. R. A., Aké Assi, L., Baniakina, J., Chibon, P., Cusset, G., ... & Sita, P. (1989). Contribution aux études ethnobotaniques et floristiques en République Populaire du Bénin. Agence de Coopération Culturelle et Technique.
  • Agyare, C., Owusu-Ansah, A., Ossei, P. P. S., Apenteng, J. A., & Boakye, Y. D. (2014). Wound healing and anti-infective properties of Myrianthus arboreus and Alchornea cordifoliaMedicinal Chemistry, 4(7), 533–539.
  • Burkill, H. M. (1985). The useful plants of West Tropical Africa (Vol. 1). Royal Botanic Gardens, Kew.
  • Fern, K. (2024). Strychnos innocuaUseful Tropical Plants Database. https://tropical.theferns.info/viewtropical.php?id=Strychnos+innocua
  • Kew Science. (n.d.). Strychnos innocua Delile. Plants of the World Online. https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:547244-1
  • Neuwinger, H. D. (1996). African ethnobotany: Poisons and drugs. Chapman & Hall.
  • Oladosu, P. O., Egharevba, H. O., Okhale, S. E., & Okogun, J. I. (2013). Phytochemical screening, antimalarial and histopathological studies of Allophylus africanus and Tragia benthamiiJournal of Pharmaceutical and Biomedical Sciences, 29(29), 684–689.
  • Omotayo, A. O., & Aremu, A. O. (2021). Undervalued spiny monkey orange (Strychnos spinosa Lam.): An indigenous fruit for sustainable food-nutrition and economic prosperity. Plants, 10(12), 2785.
  • Prance, G. T., & Jongkind, C. C. H. (2015). Loganiaceae. In Flora of West Tropical Africa. Royal Botanic Gardens, Kew.
  • Uttu, A. J., Sallau, M. S., Ibrahim, H., & Iyun, O. R. A. (2022). Isolation, characterization, and docking studies of campesterol and β-sitosterol from Strychnos innocua (Delile) root bark. Journal of Biomolecular Structure and Dynamics, 1–10.

External Links

More Pictures

 

Compounds of Strychnos innocua
References

Alagbe, J. O. (2023). Bioactive compounds in ethanolic extract of Strychnos innocua root using gas chromatography and mass spectrometry (GC-MS). Drug Discovery, 17, 1-6.