Vernonia blumeoides
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Orbivestus blumeoides Common Names: Scientific
Classification Kingdom: Plantae Clade: Tracheophytes Clade: Angiosperms Clade: Eudicots Clade: Asterids Order: Asterales Family: Asteraceae Genus: Orbivestus Species: O. blumeoides Synonyms: Vernonia blumeoides Hook.f., Cacalia blumeoides Kuntze (accepted as Orbivestus blumeoides in recent taxonomic treatments). The
species was transferred from Vernonia to Orbivestus based on morphological
evidence. (Isawumi, 2008) Morphological Description Orbivestus blumeoides (syn. Vernonia blumeoides) is a perennial herb or subshrub, generally
0.5–2 m tall, occasionally forming a more robust, weakly woody base. Stems may
be erect or somewhat sprawling, often much-branched in open habitats. (Isawumi,
2008) · Stems: Slender to moderately robust, green to purplish, variably
pubescent (short hairs) to subglabrous, often weakly ribbed; older basal portions
may become woody and brownish. (Herbarium observations; morphology review) · Leaves: Alternate, concentrated towards the upper parts of the
stems; blade lanceolate to ovate-lanceolate (typically 5–15 cm long × 2–5 cm
wide) with serrate to crenate margins, acute to acuminate apex, and cuneate
base. Surfaces are sparsely hairy and dotted with small glands, especially on
the underside; venation pinnate and clearly visible. (Flora records) · Inflorescences: Terminal and upper axillary corymbs
bearing clusters of small capitula (flower heads) about 5–8 mm in diameter.
Each capitulum comprises numerous tubular florets, usually lilac to purple,
with five-lobed corollas and exserted dark anthers; involucral bracts are
arranged in several series, somewhat imbricate, and often tinged purplish.
(Flora records) · Fruit: Narrow cylindrical achenes (c. 2–3 mm long), ribbed,
surmounted by a persistent pappus of numerous white to brownish bristles,
facilitating wind dispersal. · Diagnostic Features: Among Orbivestus species, O. blumeoides is
distinguished by its medium-sized, shortly pedunculate heads in terminal
corymbs, lanceolate serrate leaves, and its restricted West-Central African
distribution. (Isawumi, 2008; Kew POWO database) Distribution and Habitat Orbivestus blumeoides is
a West African species with a relatively narrow native range. Plants of the
World Online records it as native to Nigeria, Cameroon, and the Gulf of Guinea
islands (Bioko). (Kew Science, n.d.) · Geographic Range: Herbarium records place the species from
lowland and montane zones in Cameroon (including Mt Cameroon), southern
Nigeria, and Bioko Island. (Kew Science, n.d.) · Habitat: Occurs in open or lightly shaded sites such as forest
margins, secondary woodland, bush fallows, and savanna–forest transition zones.
Several herbarium labels describe plants growing on rocky slopes, dry river
beds, and gully margins with well-drained, often stony or sandy loam soils.
(Herbarium & field records) · Ecological Role: As an erect herb or subshrub with
conspicuous purple heads, it contributes to herbaceous layer diversity and
provides nectar sources for bees and butterflies; the pappus-bearing achenes
aid wind dispersal and colonization of disturbed habitats. (Field ecology
observations) Ethnopharmacology In ethnomedicine,
Orbivestus blumeoides is much better known under its synonym Vernonia blumeoides. Surveys in northern Nigeria report that it is
sold in medicinal plant markets and used in combination with other herbs,
primarily for malaria, gastrointestinal complaints, and various infections.
(Aliyu et al., 2011) Traditional Uses · Malaria and febrile illnesses: Decoctions of the aerial parts are used in
northern Nigeria and Cameroon to treat malaria and “fevers,” frequently in
multi-herbal mixtures. (Batana et al., 2025; Aliyu et al., 2015) · Diarrhea and gastrointestinal disorders: Ethnomedical reports from Zaria (northern
Nigeria) indicate use of the aerial parts for diarrhea and other infectious
gastrointestinal conditions, consistent with the plant’s documented
antibacterial activity. (Aliyu et al., 2011) · Skin and soft-tissue infections: Crude extracts of V. blumeoides are
traditionally applied or ingested for treatment of skin and soft-tissue
infections, aligning with in vitro activity against Gram-positive bacteria such
as Staphylococcus aureus. (Aliyu et al., 2011; Aliyu et al., 2015) · General tonic and inflammatory conditions: As with other medicinal Vernonia species
in West Africa, preparations of V. blumeoides are used as general tonics and
for relief of pains and inflammatory complaints, although detailed ritual or
dosage practices are less well documented than for the closely related species.
(Traditional medicine surveys) Pharmacological Studies Antibacterial and Antimicrobial Activity · Broad-spectrum antibacterial activity of crude
extracts: A comparative
study on three Vernonia species demonstrated that 50% ethanol extracts and
chloroform fractions of V. blumeoides (aerial parts) produced zones of
inhibition ranging from 14 to 27 mm against clinical isolates such as
Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Salmonella
typhi, Klebsiella pneumoniae, and Corynebacterium ulcerans. Minimum inhibitory
concentrations (MIC) for active fractions fell between 1.25 and 2.5 mg/mL,
indicating broad-spectrum activity against both Gram-positive and Gram-negative
bacteria. (Aliyu et al., 2011) · Antibacterial eudesmanolide lactone: The eudesmanolide sesquiterpene lactones
isolated from V. blumeoides showed “limited but interesting” antibacterial
activity in microdilution assays, particularly against Bacillus,
Staphylococcus, and Streptococcus species, supporting their contribution to the
antibacterial effects of crude preparations used for diarrhea and infections.
(Aliyu et referenced in 2015) Antiplasmodial and Antioxidant Activity · In vitro antiplasmodial activity: Recent work tested ethanol extract and
solvent fractions of V. blumeoides against both chloroquine-sensitive (3D7) and
chloroquine-resistant (Dd2) strains of Plasmodium falciparum. The median
inhibitory concentrations (IC₅₀) ranged from 4.70 to over 100 µg/mL, with the
ethyl acetate fraction showing the strongest antiplasmodial activity (lowest
IC₅₀), thus validating traditional antimalarial use. (Batana et al., 2025) · Antioxidant capacity: In the same study, extracts and fractions
displayed strong free radical–scavenging and reducing capacity in ABTS, DPPH
and FRAP assays (median scavenging concentrations 31.17–124.1 µg/mL (ABTS),
50.84–500 µg/mL (DPPH), 33.95–500 µg/mL (FRAP)). This antioxidant activity
aligns with the high phenolic and flavonoid content, suggesting a role in
countering oxidative stress associated with infections. (Batana et al., 2025) Anti-virulence / Quorum-Sensing Inhibition · Quorum-sensing inhibition: The eudesmanolide sesquiterpene lactones
(blumeoidolides A–D) from V. blumeoides were shown to inhibit quorum-sensing
regulated violacein production in Chromobacterium violaceum biosensor assays at
sub-inhibitory concentrations, suggesting an anti-virulence mode of action
rather than outright bactericidal effect. (Aliyu et al., 2016) · Molecular docking studies: In silico docking supports that
blumeoidolides can fit into bacterial quorum-sensing receptor binding sites,
reinforcing their potential as leads for anti-virulence agents. (Aliyu et al.,
2016) ⚠ Toxicity Profile & Safety: Compared to many widely used medicinal plants,
toxicological data for Orbivestus blumeoides remain limited; available evidence
suggests caution. Low cytotoxicity in
vitro In the 2025
antiplasmodial/antioxidant: study, V. blumeoides extracts (including active
fractions) showed negligible toxicity toward murine macrophage RAW cells in
resazurin viability assays. (Batana et al., 2025). Potential allergenicity of sesquiterpene
lactones Eudesman: olide
sesquiterpene lactones are electrophilic molecules; in related Asteraceae, such
compounds are known to cause contact dermatitis or sensitization in susceptible
individuals. Although no human data exist for V. blumeoides, repeated topical
or oral use may pose similar risks. (Aliyu et al., 2015; Aliyu et al., 2016). Because
long-term and in vivo toxicity data are scarce, the use of O. blumeoides should
be approached cautiously. It should not be used during pregnancy or in young
children, and therapeutic use is best supervised by knowledgeable
practitioners. Concentrated sesquiterpene-lactone preparations and prolonged
high-dose use warrant careful monitoring. Additional Information · Taxonomic notes: The transfer of Vernonia blumeoides to Orbivestus blumeoides reflects a broader taxonomic revision of
African Vernonieae — separating morphologically and chemically distinct groups.
(Isawumi, 2008) · Ecological significance: Herbarium data from Mt Cameroon and other
localities describe the species in light forest, rocky gullies, and disturbed
sites, indicating a role as a resilient component of herbaceous and shrubby
layers in transitional vegetation zones. · Research relevance: The combination of antiplasmodial,
antioxidant, antibacterial, and anti-virulence (quorum-sensing inhibitory)
activities makes Orbivestus blumeoides an emerging model species for studying
multi-target anti-infective strategies, particularly those focused on disarming
pathogens rather than killing them outright. (Batana et al., 2025; Aliyu et
al., 2016) References
External Links More Pictures |
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| Compounds of Vernonia blumeoides |
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| References | Aliyu, A. B. (2017). Phytochemistry and quorum sensing inhibitory studies of four
vernonia species growing in Nigeria (Doctoral dissertation). |