Tithonia rotundifolia
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Tithonia rotundifolia Common Names: Mexican sunflower, Red sunflower, Red
torch Scientific
Classification Kingdom: Plantae Clade: Tracheophytes Clade: Angiosperms Clade: Eudicots Clade: Asterids Order: Asterales Family: Asteraceae Genus: Tithonia Species: T. rotundifolia Synonyms: Tagetes rotundifolia Mill., Tithonia aristata Oersted, Tithonia speciosa (Hook.) Hook. ex Griseb., Tithonia uniflora Desf. ex J.F.Gmel., Urbanisol aristatus (Oerst.) Kuntze, Urbanisol heterophyllus (Griseb.) Kuntze, Urbanisol tagetiflora Kuntze, Verbesina szyszylowiczii (Kuntze) Hieron Morphological Description Tithonia rotundifolia is a fast-growing annual or short-lived perennial, typically
0.8–1.5 meters tall in cultivation, but can reach 4 meters in its native
habitat. Its key characteristics include: · Stems: Erect, branched, green to purplish, pubescent, becoming
woody at the base. · Leaves: Deltoid to lanceolate (10–38 cm × 5–30 cm), occasionally
lobed, greyish-green above, hairy beneath; petioles 2–10 cm long (Prance &
Jongkind, 2015). · Flowers: Bright orange to red, daisy-like (5–8 cm diameter), in
terminal capitula; ray florets 8–12, disc florets numerous; bloom from
mid-summer to fall (Kew Science, n.d.). · Fruit: Brown achenes (<1 cm), with two unequal deciduous wings;
pappus of scales aiding wind dispersal. Distribution and Habitat Tithonia rotundifolia is native to North and Central America and has become
invasive in parts of Africa and Asia: · Geographic Range: Native to Mexico, Central America,
Florida, Louisiana, and the West Indies; introduced to Nigeria, South Africa,
India, and Southeast Asia; invasive in Nigeria’s savanna regions (Kew Science,
n.d.). · Habitat: Thrives in fields, woody areas, ruderal sites, and
roadsides; prefers well-drained, sandy or loamy soils (pH 5.5–7.0) with annual
rainfall of 800–1,500 mm; occurs at altitudes below 1,580 m · Ecological Role: Acts as a pioneer species in disturbed
areas; attracts pollinators like bees and butterflies; invasive traits include
allelopathic effects, competing with native vegetation (Omokhua, 2018). Ethnopharmacology Tithonia rotundifolia has limited but significant use in traditional medicine,
particularly in its native range, with emerging pharmacological validation (Omokhua,
2018): · Antimicrobial: In Venezuela, leaf extracts treat fever and infections.
Ethyl acetate leaf extracts inhibited Staphylococcus aureus, Escherichia coli, and Mycobacterium smegmatis (MIC: 0.01–0.07 mg/mL),
outperforming Tithonia diversifolia in some strains, attributed to tagitinin A, a sesquiterpene
lactone (Omokhua, 2018). · Anti-inflammatory Potential: While not widely documented for T. rotundifolia, its close relative T. diversifolia shows anti-inflammatory effects via
flavonoids and sesquiterpene lactones, suggesting similar potential due to
shared phytochemicals like germacranolides (Mabou Tagne et al., 2018). · Antipyretic: In Venezuela, leaf decoctions are used to reduce fever,
supported by the presence of flavonoids, though specific studies on T. rotundifolia are lacking (Omokhua, 2018). · Wound Healing: In Nigeria, leaf pastes are applied to wounds. The
antimicrobial properties of leaf extracts suggest potential for tissue repair,
though direct studies are needed. · Antioxidant Potential: Leaf extracts contain phenolic compounds
and flavonoids, which may contribute to antioxidant activity, as seen in
related Tithonia species, but
specific data for T. rotundifolia is scarce (Mabou Tagne et al., 2018). ⚠ Toxicity Profile: Tithonia rotundifolia has no widely reported toxic effects at
therapeutic doses, and toxicity tests showed no cytotoxic or
mutagenic/genotoxic effects in leaf extracts. Unlike Tithonia diversifolia, which is cytotoxic at higher
concentrations, T. rotundifolia appears safer, with no significant toxicity in Artemia salina assays. However, chronic use or high doses
may cause mild gastrointestinal discomfort due to sesquiterpene lactones. Use
is contraindicated in pregnancy and for children due to insufficient safety data.
Potential heavy metal contamination in wild-harvested plants requires caution (Omokhua,
2018). Phytochemistry The medicinal properties
of Tithonia rotundifolia are driven by its phytochemical profile, though less studied
than Tithonia diversifolia (Omokhua, 2018): · Sesquiterpene Lactones: Tagitinin A, germacranolides, and
eudesmanolides, responsible for antimicrobial activity (Omokhua, 2018). [](https://pmc.ncbi.nlm.nih.gov/articles/PMC6171246/) · Flavonoids: Present in leaves, contributing to potential antioxidant and
anti-inflammatory effects (Mabou Tagne et al., 2018). · Phenolics: High phenolic content in leaves, supporting antimicrobial
and antioxidant properties (Omokhua, 2018). [](https://pmc.ncbi.nlm.nih.gov/articles/PMC6171246/) · Tannins: Found in leaf extracts, enhancing astringent and
wound-healing effects. · Essential Oils: Trace amounts, potentially aiding
antimicrobial activity, though specific compounds are not well-documented
(Prance & Jongkind, 2015). Additional Uses · Ornamental: Cultivated in Nigeria for its vibrant orange-red flowers,
used in borders and pollinator gardens. · Ecological: Attracts pollinators like bees and butterflies; used in
agroforestry for soil stabilization, though its invasiveness requires
management (Omokhua, 2018). [](https://pmc.ncbi.nlm.nih.gov/articles/PMC6171246/) · Cultural: In Nigeria, the plant is occasionally used in rituals for
spiritual cleansing, reflecting its ethnobotanical significance (Burkill,
1985). · Agricultural: Used as a green manure in some regions, though its allelopathic
effects can harm crops. References
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| Compounds of Tithonia rotundifolia |
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