Tridax procumbens (T. procumbens) Linn. is a medicinal plant found in tropical, sub-tropical and mild temperate regions around the world being used in Ayurveda treatment for liver disorders, boils, blisters, cuts, wound healing and as an anticoagulant, antifungal, and insect repellent. The plant is known to contain flavonoids, alkaloids, carotenoids, hydroxycinnamates, lignans, benzoic acid derivatives, phytosterols and tannins. The plant is also associated with endophytes to produce secondary

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... etabolies by endophytes possessing antibacterial and antifungal activities. Different parts of this plant and essential oil are associated with ethnopharmacological properties like wound healing, antibacterial, immunomodulation, antiinflammatory, antidiabetic, vasorelaxant, antihyperlipidemic, anticancer, antiplasmodial, anticoagulation and antihepatic. Most of these studies validate the concept of earlier claims that T. procumbens's potential as a medicinal plant. Further studies are required to unravel other pharmacological activities as well as the target-based mechanism of actions. The review also highlights the need for exploring lead molecules from these myriad of compounds that are of vital importance in drug discovery strategies. The plant has an average height of around 20-60 cm and is branched. Leaves are 4-8 cm long, simple, opposite and stipulate. Inflorescence is around 12-32 cm, oval shaped and held by peduncle, with ray florets and disc florets. Flowers are daisy like with yellow centred white or yellow petals. Numerous, tubular disc florets are surrounded by a ring of short, strap-shaped ray florets. Fruit is cypsela, black or brown in colour at maturity and surrounded with feathery bristles [2] . The stem is cylindrical and covered with hairs of about 1 mm with tap root system [3] . The registered number of chromosome present in Tridax are 36 (2n) [4] . Growth of plant takes place during monsoon season as it requires abundant water for growth and sustenance. PHYTOCHEMICAL CONSTITUENTS The leaf and other parts of T. procumbens L. are reported to have flavonoids, alkaloids, carotenoids, hydroxycinnamates, lignans, benzoic acid derivatives, phytosterols, tannins, crude proteins, crude fiber, soluble carbohydrates and calcium oxide [5] . The presence of fumaric acid, β-sitosterol and the pentacyclic triterpenoid oleanolic acid have also been reported [5] . Luteolin, glucoluteolin, quercetin, and isoquercetin have been reported in flower extracts [6] . Some of the other phytochemicals present abundantly in T. procumbens are 2,6-dihydroxyacetophenone, 2-O-β-D-glucopyranoside, echioidinin, pinostrobin, dihydroechioidinin, tectochrysin-5-glucoside, methyl salicylate glucoside, 5,7,8-trimethoxyflavone, skullcapflavone-2-methyl ether, androechin, tectochrysin, 5,7,2'-trimethoxyflavone, echioidin, skullcapflavone ii, 5,7-dimethoxyflavone and andrographidine [6]. Flavonoids A recent study has demonstrated the presence of twenty three flavonoids in T. procumbens [7] with total content around 65 g/kg. Kaempferol and catechin and its derivatives (-)-epicatechin, (+)-catechin, (-)-eigallocatechin, (+)-gallocatechin, (-)epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate) account for about 17.59% and 26.3% respectively. The remaining 56.11% represent sixteen flavonoids namely biochanin, apigenin, naringenin, daidzein, quercetin, butein, robinetin, baicalein, nobiletin, genistin, ellagic acid, luteolin, myricetin, baicalin, isorhamnetin and silymarin (Figure 1 and 2) [7].