Phytochemical analysis, antioxidant and antimicrobial activity of wild and derived plants of Hook - An endemic species from Western Ghats, India.

Hook (Asclepiadaceae), an endemic plant species, due to habitat destruction and over exploitation has a very restricted distribution in the Western Ghats of Tamil Nadu, India. The present wrok aimed to determine the chemical composition, the total phenolic (TPC), flavonoid (TFC) and tannin content (TEC), and to assess the antioxidant properties of various extracts of plants (IVP) and regenerated plants (IRP) of . Some phenolic compounds like gallic acid, cathechol, vanillin and salicylic acid were identified and quantified by HPLC. All the extracts possessed relevant radical scavenging activity on DPPH, Superoxide radical scavenging activity, and Nitric oxide radicals as well as total antioxidant ability. DPPH assay of methanol stems extracts and ethanol leaves extracts revealed the best antioxidant properties with important IC values of 0.248 ± 0.45 µg/mL and 0.397 ± 0.67 µg/mL, respectively, whereas chloroform stems extracts showed a lower antioxidant activity (IC of 10.99 ± 0.24 µg/mL). The IRP methanol extracts of stem and leaves had good inhibitory activity against all tested microorganisms in a dose-dependent manner. These results suggested that raised plants of are an excellent source of antioxidant compounds to be exploited on an industrial level as food additive.