Napoleonaea imperialis
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Napoleonaea imperialis Common Names: Napoleons Hat, Napoleons Buttons Scientific
Classification Kingdom: Plantae Clade: Tracheophyta Class: Magnoliopsida Order: Ericales Family: Lecythidaceae Genus: Napoleonaea Species: N. imperialis Synonyms: Belvisia
caerulea Desv., Napoleona whitfieldii Decne., Napoleonaea cuspidata Miers,
Napoleonaea miersii Hook.f. Morphological Description Napoleonaea imperialis
is a slow-growing, evergreen shrub or small tree, reaching 3–7 m in height. Key
features include: · Stems: Woody, with a dense, low-branching crown; bark
greyish-brown, smooth to slightly fissured · Leaves: Alternate, simple, elliptic to obovate, 10–25 cm long, 5–10
cm wide; glossy dark green, leathery, with entire margins · Flowers: Cauliflorous, solitary, 5–8 cm in diameter; multi-colored
(yellow, red, purple), with a complex structure resembling passionfruit
flowers; outer petals broad, inner corona intricate · Fruit: Flattened, globose berries, 3–5 cm in diameter; green when
immature, ripening to red-brown; pulp fleshy, containing 10–20 seeds Distribution and Habitat Napoleonaea imperialis
is native to West Africa, ranging from southern Benin to Nigeria and extending
to Cameroon and Gabon. It thrives in: · Habitats: Understory of lowland rainforests, secondary forests,
riverine forests, and swampy areas at elevations of 0–500 m · Ecological Conditions: Prefers humid climates with annual
rainfall of 2,000–3,500 mm, temperatures of 22–30°C, and well-drained, fertile
soils (pH 4.5–6.0) · Range in Nigeria: Common in southern regions, particularly
in Cross River and Delta States, where it is used medicinally and culturally Ethnopharmacology Napoleonaea imperialis is a medicinal plant traditionally used in
parts of West Africa for treating various ailments, and several studies support
its pharmacological potential. Extracts of its leaves and roots have
demonstrated significant antidiarrhoeal, antimicrobial, antioxidant, and
anti-inflammatory activities in laboratory and animal studies. Ethanol-leaf
extracts reduced diarrhoea and gut motility in mice, supporting its folkloric
use for gastrointestinal disorders, while ethyl acetate extracts showed
inhibitory effects against bacteria such as E. coli and Pseudomonas aeruginosa.
Phytochemical screenings revealed the presence of bioactive compounds like
alkaloids, saponins, tannins, flavonoids, glycosides, and glycosylated
stigmasterol, which may underlie these effects. Additionally, antioxidant
assays confirmed free-radical scavenging and membrane-stabilizing properties,
and haematological evaluations in rats showed no major toxicity at moderate
doses. Traditionally, the plant’s bark and fruit pulp are also used to treat pulmonary
problems and wounds. · Antimicrobial Activity: Leaf and seed n-hexane extracts inhibit
Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa (MIC 50–100
μg/mL), attributed to linalool (39–66.8%) and estragole (17.1–43.1%),
supporting use for wound healing and infections (Ndukwe et al., 2018). · Pulmonary Conditions: Bark and fruit pulp are chewed to
alleviate cough and asthma, potentially due to anti-inflammatory flavonoids and
terpenoids, though specific studies are limited (Burkill, 1995). · Molluscicidal Properties: Seed extracts containing napoleogenol,
napoleogenin, and napoleonaside exhibit molluscicidal activity (LC₅₀ 10–20 ppm)
against Biomphalaria glabrata, supporting use in schistosomiasis control
(Irvine, 1961). · Hypertension Management: Leaf decoctions are used in Nigeria to
manage hypertension, possibly linked to glycosylated stigmasterol, which
modulates vascular tone, though further validation is needed (Ndukwe et al.,
2018). Phytochemical analyses
identify volatile compounds (e.g., linalool, estragole, citral, geranial,
neral, D-limonene, citronellol, trans-nerolidol) in essential oils (0.78–1.23%
yield) and non-volatiles (e.g., glycosylated stigmasterol, flavonoids,
alkaloids, saponins) in leaves and seeds. These compounds underpin its
antimicrobial, anti-inflammatory, and molluscicidal effects (Ndukwe et al.,
2018; Burkill, 1995). ⚠ Toxicity Profile: Seeds of Napoleonaea imperialis contain
bioactive compounds (e.g., napoleogenol, alkaloids) with potential toxicity,
causing gastrointestinal distress at high doses (LD₅₀ >2,000 mg/kg in rats).
No acute toxicity is reported for leaf or bark extracts at medicinal doses, but
prolonged use may lead to alkaloid accumulation. The mucilaginous fruit pulp
may cause mild skin irritation. Pregnant women and individuals with liver
conditions should avoid use due to insufficient safety data. Consult
practitioners before medicinal use (Burkill, 1995). Additional Uses · Ornamental: Cultivated in tropical gardens for its vibrant flowers and
glossy foliage, often used as a hedge or specimen plant. · Cultural: Named after Napoleon Bonaparte in 1804, reflecting its
historical significance; used in Igbo and Yoruba rituals in Nigeria for healing
and protection (Kew Science, n.d.). · Ecological: Supports pollinators (bees, butterflies) and seed dispersers
(birds, bats), enhancing rainforest biodiversity; stabilizes understory soils
(Burkill, 1995). · Traditional Oral Hygiene: Twigs are used as chew-sticks in Nigeria,
with citral (30% in twig oil) contributing to oral antimicrobial effects (Ndukwe
et al., 2018). References
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| Compounds of Napoleonaea imperialis |
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