Abstract

Gas chromatography-mass spectrometry (GC-MS) analysis and antioxidants activity of phytochemical constituents from ethyl acetate fraction of Vernonia calvoana (V.C) was evaluated. The fraction was subjected to GC–MS analysis using 5% diphenyl 95% dimethylpolysiloxane (30 m × 0.25 mm ID × 0.25 µm film thickness), the compounds were separated and identified by Turbo gold mass detector. The antioxidants activity was investigated employing the 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH) and Ferric reducing antioxidant power (FRAP) scavenging method. Eighteen different phytochemical compounds namely: Etylobenzene (22.13%), isopropylidenecyclopentadiene (8.24%), 1-ethyl-2-methylbenzene (8.64%), decane (15.24%), 1,2,3-trimethylbenzene (12.51%), 2,7-Dimethyloctane (5.79%), 4-methyltridecane (0.72%), tetrahydro-2-furanmethanol (2.44%), 3,3-Dimethylhexane (0.54%), 5-methylundecane (0.74%), 1-Nonyne (2.16%), 1-pentadecane carboxylic acid (4.70%), 2,6-Dimethyl-1,7-octadien-3-ol (4.00%), cis-9-octadecanoic acid (5.49%), n-Nonadecanoic acid (1.53%), Nonyl propyl ester (1.84%), 5,8-octadecadienoic acid (1.79%), and 9,12,15-octadatrienal (1.53%) were identified. Increase in activity was observed in both the DPPH and FRAP analysis, and were concentrations dependent and closely related to ascorbic acid. The phytochemical components using GC-MS and antioxidant activity of ethyl acetate extract of V.C have been evaluated. In addition to this, further isolation and characterization of individual components would provide more insight to its use in the production of new drugs of therapeutic value.

Key words:  1, 1-diphenyl-2-picrylhydrazyl radical (DPPH), Ferric reducing antioxidant power (FRAP), gas chromatography, Vernonia calvoana, antioxidants.