Two new flavones from Tridax procumbens Linn.

Area of Science:

• Phytochemistry
• Natural Products Chemistry
• Pharmacology

Background:

• Tridax procumbens Linn. is a plant with a history of traditional medicinal use.
• Flavonoids are a class of plant secondary metabolites known for diverse biological activities.
• Understanding the chemical constituents and bioactivities of medicinal plants is crucial for drug discovery.

Purpose of the Study:

• To isolate and characterize novel compounds from Tridax procumbens Linn.
• To evaluate the antioxidant potential of newly identified flavones.
• To compare the antioxidant activities of the isolated compounds.

Main Methods:

• Isolation of compounds using chromatographic techniques.
• Structure elucidation utilizing spectroscopic methods including IR, 1D and 2D NMR, ESI-MS, and HR-ESI-MS.
• Antioxidant activity assessment via 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) assays.

Main Results:

• Two new flavones, 8,3'-dihydroxy-3,7,4'-trimethoxy-6-O-β-D-glucopyranosyl flavone (1) and 6,8,3'-trihydroxy-3,7,4'-trimethoxyflavone (2), were successfully isolated and characterized.
• Four known compounds: puerarin (3), esculetin (4), oleanolic acid (5), and betulinic acid (6) were also identified.
• Both new flavones demonstrated notable antioxidant activity, with compound 2 exhibiting stronger activity than compound 1 in both DPPH and FRAP assays.

Conclusions:

• Tridax procumbens Linn. is a rich source of bioactive flavones.
• The newly discovered flavones possess significant antioxidant properties.
• Compound 2 represents a promising candidate for further investigation as a natural antioxidant agent.