46C-8 |
Antioxidant activity of chopé (Gustavia augusta L.) extracts |
J. MANCINI-FILHO1, R. P. Torres, and D. E. Garcia-Torres. (1) Food Science and Nutrition Department, São Paulo University, Av.Prof. Lineu Prestes, 580, São Paulo - SP, 05508-900, Brazil Oxidation of food lipids under environmental conditions (temperature, air, light) leads to the production of peroxides, aldehydes, ketones and others compounds. The oxidation can be prevented by adding synthetic or natural antioxidants. There is a great interest in plant phenolic compounds because of their potential role as natural antioxidant. Chopé (Gustavia augusta L.) is one fruit from Amazonia with 13% of lipids that is used as food. Chopé samples were obtained from Amazonia, dried at 60°C, milled (32 mesh sieve) and submitted to sequencial extraction using as solvent: ether, ethanol and water. The antioxidant activities in the etheric, ethanolic and aqueous extracts, measured by b carotene/linoleic acid system were: 43%; 40% and 72%, respectivety and in the control BHT (100 ppm) the antioxidant activity was 65%. The antioxidant activities of the same extracts measured in lipid medium in RANCIMAT system showed increase in the induction period similar to BHT (100 ppm). Three phenolic fractions were obtained by tetrahydrofuran extraction: free phenolic acids, soluble phenolic esters and insoluble phenolic esters that inhibited the oxidation process in b carotene/linoleic acid system in 89%; 83% and 87%, respectively. The phenolic acids were identified by gas chromatograph equipped with capillary column and flame ionization detector, on the basis of relative retention times compared with standards. The fractions showed the presence of following phenolic acids: salicylic, trans-cinamic, hydroxibenzoic, vanilic, o-cumaric, protocatechinic, gallic, ferulic, cafeic and sinaptic. The presence of phenolic compounds in chopé fruit extracts may be responsible for its higher antioxidant activity and the results obtained are suggesting that the chopé extracts can be used as food antioxidant.
Session 46C, Food Chemistry: Lipids, antioxidants and emulsifiers
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