RESUMO
Objective: To investigate the photochemical constituents present in methanol extract of martynia annua seeds using Gas Chromatography-Mass Spectroscopy(GC-MS), High-Performance Thin–Layer Chromatography(HPTLC) analysis and study antioxidant activity. Methods: Methanol extract of Martynia annua seeds were subjected to GC-MS and HPTLC analysis. HPTLC analysis was carried out using GAMAG system with a linomate5 applicator, system mobile phase (Toluene: Chloroform: Ethanol (4:4:1 V/V/V)), two different volume of extract was applied 2 µl and 5 µl. GC-MS analysis was carried out on JEOL GC MATE ΙΙ, column HP 5 MS and Quadruple double focusing mass analyzer. Antioxidant activity was determined by DPPH assay. Results: GC-MS analysis provided 17 peaks indicating the presence of seventeen different phytochemicals in methanol extract of martynia annua seeds. HPTLC fingerprint showed 6 peaks at both size 2 µl and 5 µl at 254 nm whereas 4 peaks, 9 peaks were detected at 366 nm for 2 µl and 5 µl respectively. After derivatization with 10 % methanolic sulphuric acid, 8 peaks, 11 peaks were detected for 2 µl and 5 µl respectively when the derivatized plate was scanned at 540 nm. DPPH free radical scavenging result showed EC50 value of 44.1±1.1 µg/ml. Conclusion: The GC-MS analysis showed the presence of fatty acids, ester, aldehydes and ketones whereas in HPTLC different peaks at different UV-lights before and after derivatization were observed. Maximum percentage inhibition using DPPH assay was found 74 at concentration of 50 µg/ml.