Spathodea campanulata

Spathodea campanulata

Spathodea campanulata

Common Names: African tulip, scarlet bells
Local Names: Oruru, Mojutoro (Yoruba, Nigeria), Imi ewu (Igbo, Nigeria)
Species ID: NMP-167 | wfo-0001348910

Scientific Classification

Kingdom: Plantae

Clade: Tracheophytes

Clade: Angiosperms

Order: Lamiales

Family: Bignoniaceae

Genus: Spathodea

Species: S. campanulata

Binomial Name: Spathodea campanulata P. Beauv.

Synonyms: Spathodea nilotica Seem.

Morphological Description

Spathodea campanulata, commonly known as the African tulip tree, is a medium-sized, deciduous tree that typically grows to heights of 10–35 meters, with exceptional specimens reaching up to 40 meters under ideal conditions (Gilman et al., 2018). The trunk, often buttressed at the base, supports a round, heavy crown of dense, dark green foliage, with pinnate leaves that are glossy above and paler beneath, measuring 30–50 cm long and comprising 5–19 leaflets, each 7–15 cm in length (Tropical Plants Database, 2024). The tree is renowned for its striking, bell-shaped flowers, 8–12 cm long, ranging from yellow to vibrant orange-red with yellow-tipped margins, borne in terminal racemes of 10–20 blooms primarily from late winter to spring, though flowering can occur sporadically year-round in tropical climates (Ng, 2006). The fruit is a woody, boat-shaped capsule, 15–25 cm long, transitioning from green to brown as it matures, splitting open to release numerous winged seeds, each about 2 cm long, aiding wind dispersal (Gilman et al., 2018).

Distribution and Habitat

Native to Western Tropical Africa, from Senegal to Angola, Spathodea campanulata has been widely introduced and naturalized across tropical and subtropical regions globally, including Southeast Asia, Central and South America, the Caribbean, and Pacific Islands like Hawaii (CABI, 2024; Ng, 2006). It thrives in wet tropical biomes, favoring elevations from sea level to 2,000 meters, with optimal growth in areas receiving 1,200–2,500 mm of annual rainfall and temperatures of 20–30°C (Gilman et al., 2018). The tree prefers well-drained, fertile soils—loamy or sandy—with a pH of 5.5–7.0, though it exhibits moderate drought tolerance once established, making it adaptable to disturbed sites like roadsides and abandoned fields (Tropical Plants Database, 2024).

Ethnopharmacology

Spathodea campanulata, commonly known as the African tulip tree, possesses a variety of medicinal properties that have been documented in traditional medicine across tropical Africa and parts of Asia. Different parts of the plant, including the bark, leaves, and flowers, are used for therapeutic purposes. The bark is traditionally employed for treating wounds, fever, and skin infections due to its antimicrobial and anti-inflammatory properties. Extracts from the leaves and flowers have shown antidiabetic, antioxidant, analgesic, and antimalarial activities in various studies. For instance, methanolic extracts of the bark and leaves have demonstrated significant antioxidant activity attributed to the presence of flavonoids and phenolic compounds. Additionally, the plant exhibits anti-ulcer and hepatoprotective properties in animal studies, and is sometimes used as a remedy for diarrhea, dysentery, and toothaches in traditional medicine. While its broad pharmacological potential is promising, further research and clinical studies are needed to fully validate its efficacy and safety.

Antimalarial Activity: In Uganda, leaf decoctions treat malaria; stem bark extracts (200–400 mg/kg) suppressed Plasmodium berghei parasitemia by 60–75% in mice, attributed to ursolic acid and spathodic acid (Amusan et al., 1996).

·       Anti-inflammatory and Analgesic: In Ghana, bark poultices alleviate inflammation and pain. Ethanol bark extracts reduced carrageenan-induced paw edema in rats by 55% at 200 mg/kg, linked to flavonoids and phenolic compounds (Ofori-Kwakye et al., 2011).

·       Antidiabetic Effects: In Nigeria, leaf infusions manage diabetes. Aqueous extracts lowered blood glucose by 30% in alloxan-induced diabetic rats at 250 mg/kg, due to antioxidant polyphenols (Ng, 2006; N’guessan et al., 2011).

·       Antimicrobial Properties: In Cameroon, flower extracts treat skin infections and wounds. Methanol leaf extracts showed a minimum inhibitory concentration (MIC) of 125 μg/mL against Staphylococcus aureus, supporting wound-healing claims (Padhy, 2021).

These uses are bolstered by its rich chemical profile, with over 57 compounds identified, including caffeic acid and ajugol, enhancing its therapeutic potential (Heim et al., 2022).

⚠  Toxicity Profile: While Spathodea campanulata is widely used medicinally, it exhibits mild toxicity. The flowers and leaves contain iridoids and glycosides toxic to certain insects, notably bees, causing disorientation at high doses (Ng, 2006). Acute toxicity studies in rats showed no mortality at 2,000 mg/kg of bark extract, though gastrointestinal irritation occurred at higher doses (Ofori-Kwakye et al., 2011). Human toxicity is minimal when used traditionally, but excessive consumption may cause nausea or allergic reactions in sensitive individuals (Tropical Plants Database, 2024).

Additional Uses

·       Ornamental Value: Its vivid flowers make it a popular ornamental in tropical gardens and urban parks, often lining streets for shade (Gilman et al., 2018).

·       Ecological Impact: Considered invasive in Hawaii and Pacific Islands, it outcompetes native flora, forming dense stands that alter ecosystems (CABI, 2024).

·       Material Use: The lightweight wood (density 0.3–0.4 g/cm³) is used for carvings and fuel, while seeds historically served as fish poison in traditional practices (Ng, 2006).

References

  • AmusanO. O. G., Adesogan, E. K., & Makinde, J. M. (1996). Antimalarial active principles of Spathodea campanulata stem bark. Phytotherapy Research, 10(8), 692–693. https://doi.org/10.1002/(SICI)1099-1573(199612)10:8<692::AID-PTR928>3.0.CO;2-O
  • CABI. (2024). Spathodea campanulata (African tulip tree). CABI Digital Library. Retrieved April 8, 2025, from https://www.cabidigitallibrary.org/doi/10.1079/cabicompendium.51139
  • Gilman, E. F., Watson, D. G., Klein, R. W., & Hasing, G. (2018). Spathodea campanulata: African tuliptree. University of Florida Institute of Food and Agricultural Sciences. Retrieved April 8, 2025, from https://edis.ifas.ufl.edu/publication/ST600
  • Heim, S. C., Teixeira, G. F., da Silva, G. R., & Salvador, M. J. (2022). Antioxidant activity of Spathodea campanulata (Bignoniaceae) extracts. Brazilian Journal of Plant Medicine, 14(2), 287–292.
  • N’guessan, K., Kadja, B., Zirihi, G. N., Traoré, D., & Aké-Assi, L. (2011). Screening phytochimique de quelques plantes médicinales ivoiriennes utilisées en pays Krobou (Agboville, Côte-d’Ivoire). Sciences & Nature, 8(1), 1–15.
  • Ng, F. S. P. (2006). Tropical horticulture and gardening. Clearwater Publications.

  • Ofori-Kwakye, K., Kwapong, AfootnoteA., & Adu, F. (2011). Antimicrobial activity of extracts and topical products of the stem bark of Spathodea campanulata for wound healing. African Journal of Traditional, Complementary and Alternative Medicines, 6(2), 168–174. https://doi.org/10.4314/ajtcam.v6i2.57089

  • Padhy, G. K. (2021). Spathodea campanulata P. Beauv. —A review of its ethnomedicinal, phytochemical, and pharmacological profile. Journal of Applied Pharmaceutical Science, 11(12), 017–044. https://doi.org/10.7324/JAPS.2021.1101202

External Links

More Pictures

 

Compounds of Spathodea campanulata
References

Murtala Muhammad, Etal. (2023). Phytochemical analysis of Nigerian medicinal plants. NMPP-DB Project, Department of Biochemistry, Kano University of Science and Technology, Wudil