• Food Science and Preservation
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• v.18 no.1
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• pp.79-86
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• 2011

Three bark extracts of Albizia julibrissin were prepared using water (AW), 70% (v/v) ethanol (AE), and hot water (AHW). Organic solvent fractions were analyzed for total flavonoids and polyphenols, antioxidant activities, and inhibitory activities against xanthine oxidase. Total flavonoid and polyphenol contents of the AHW extract were 8.57 mg/g and 108.67 mg/g, respectively. The SOD-like activities of all extracts, assayed at 1.0 mg/mL, were 10.46-16.73%. The nitrite-scavenging ability of the AHW extract, assayed at pH 1.2, was 60.82%, and the $IC_{50}$ value was $770.18\;{\mu}g$/mL. The electron-donating ability of the AHW extract, at 0.3 mg/mL, was 92.30%; the $IC_{50}$ values of the AW and AHW extracts were $31.31\;{\mu}g$/mL and $36.22\;{\mu}g$/mL, respectively; thus higher than that of ascorbic acid ($39.06\;{\mu}g$/mL). Xanthine oxidase inhibition by the AHW extract, at 1.0 mg/mL, was 94.05%. These results indicate that the AHW of A. julibrissin has potential as a natural antioxidant, for addition to foods and nutraceuticals.