DETERMINATION OF CHEMICAL COMPOSITION, TOTAL PHENOLIC CONTENT, TOTAL FLAVONOID CONTENT AND IN-VITRO ANTIOXIDANT CAPACITY OF VARIOUS ORGANIC EXTRACTS OF GYNURA CREPIOIDES LEAVES CULTIVATED IN MALAYSIA

Gynura crepioides, also known as Okinawa Spinach, belongs to the family Asteraceae, which is known to possess various medicinal properties. The present study was thus aimed at determining the GC-MS based chemical profiling, total phenolic content (TPC), total flavonoid content (TFC) and anti-oxidant (AO) capacity of the organic crude extracts such as hexane, chloroform-ethyl acetate, obtained from the extraction of the leaves of G. crepioides by application of Folin-Ciocalteu method, aluminium chloride calorimetric method and DPPH radical scavenging assay, respectively. The results obtained from UV-VIS microplate spectrophotometer indicated a high amount of phenolic and flavonoid content in the leaves. Ethyl acetate extract was found to display highest TPC (10.09 ± 0.20 mg GAE/g) and TFC (9.56 ± 0.22 mg QE/g). Interestingly, ethyl acetate extract also displayed highest AO capacity with IC₅₀ value of 0.74 mg/mL as compared to chloroform and hexane extracts with IC₅₀ values of 0.90 mg/mL and 1.50 mg/mL, respectively with respect to the standard BHT (IC₅₀=0.04 mg/mL). GC-MS revealed the presence of sulfurous acid, 2-ethylhexylisohexyl ester (11.53%) as a major compound in hexane extract, stigmasterol (13.80%) in chloroform extract and squalene (21.32%) in ethyl acetate extract, respectively. The results suggested that G_. crepioides has the potential to be a source of alternative medicine due to its reportedly good anti-oxidant properties.