Antioxidant Activity of Duwet Seed (Syzygium cumini Linn.) Extract on Lipid Peroxidation Models in Vitro

All parts of Syzygium cumini Linn. (duwet) were widely used for medicinal plant in the treatment of various deseases. The seed extract was used to lower blood glucose. Cumini's seed had higher phenolic fractions than others. It were prepared by extracted of duwet seed "Genthong" varieties, using various extractants such as 85% ethyl acetate, 50% methanol and 50% ethanol. Duwet seed extract collected then was determined of phenolics compound and antioxidant activity assayed by measuring 2,2-diphenyl-1-picrylhydrazylradical (DPPH) scavenging activity, reducing Ferric ion (Fe3+) power and inhibition of linoleic acid oxidation. The objective was to select one of the extractant which gave highest yield and polyphenolic content and its stronger antioxidant activity. Extractant 50% methanol gave highest the extract yields was 16.29 % (db.) and phenolics compounds of extract was composed: total phenolic 45.99+/-0.25 g-GAE/100 g-extract; total flavonoid 2.28+/-0.07 g-QE/100 g-extract and total tannin 26.9+/-0.07 g-TAE/100 g-extract. All of extract exhibited strong on behalf of RSA-DPPH assay 87-95% (100 mu g-mL(-1)) and reducing power, nevertheless in inhibition of linoleic acid oxidation was moderate 49-55% (400 mu g-mL(-1)).