K K Srinivasan

Shorearobusta widely distributed in moist and dry forest in the tropics, has been paradoxically described as deciduous, semi-decidous or evergreen species. The resin is astringent sweet acrid, cooling anodyne, vulnerary, antibacterial, deodorant constipating and detergent. It is useful in hyperhydrosis, vitiated conditions of pitta, wound ulcers, pruritis, fractures, fever, diarrhoea, dysentery etc. The main aim of the present study was to carry out the in vitro antioxidant activity of ethanolic extract Shorearobusta oleoresin and GC-MS analysis of the oil obtained from petroleum ether fraction by column chromatography. In vitro antioxidant activity screening was done by oxygen radical scavenging assay such as DPPH and Iron chelating method and the IC50 was found to be 357.44and 151.27µg/mlusing ascorbic acidas standardwith IC50 value of 52.28 and 17.85µg/mlrespectively.Total antioxidant was 94.95µg equivalent to that of ascorbic acid.Thirty chemical constituents have been identified by GC-MS; the major chemical constituents are 7-Tetracyclo [6.2.1.0(3.8)0(3.9)]undecano (7.23%), Bis(2-ethylhexyl) phthalate (7.06%),3-Octenoic acid, methyl(tetramethylene)Si (6.25), Ursa-9(11),12-dien-3-ol (4.96%), phenol (4.68%) and 1-Fluoroforskolin (4.08%).