Journal of Enzyme Inhibition and Medicinal Chemistry · 2009 · 23 citations · 33 references
Life SciencesBotanyPlant BiologyEthnobotanyFood ChemistryPlant BiochemistryAntioxidant DefensePhenolic Compound AnalysisPhenolic Profile AnalysisAntioxidant Activity AssaysFree Radical ScavengingLinoleic Acid PeroxidationPhenolic Compound Antioxidant CapacityPhenolic CompoundsPhenolic Content AnalysisPlant Extract AntioxidantsTotal Phenolic Content
Enzyme-assisted water extracts (EWEDL) and ethanol extracts of Du-zhong leaves (EEDL) were evaluated for their antioxidant activities using the DPPH radical-scavenging assay, Fe(2+)-chelating assay, and inhibition ability of the linoleic acid peroxidation assay. In general, the antioxidant activity of Du-zhong leaf extracts increased with increasing concentration. Based on the two extracting methods with different antioxidative reactions, it was shown that the enzyme-assisted water extracting method was more effective for antioxidant extraction from Du-zhong leaves. By HPLC-MS analysis, the main phenolic compounds (geniposidic acid, epicatechin, and chlorogenic acid) identified in EWEDL and EEDL were similar. EWEDL and EEDL had total phenolic contents of 13.84 +/- 0.11 and 14.72 +/- 0.14 mg chlorogenic acid equivalents (CAE) in each gram of extract, respectively. However, there was no positive correlation between total phenolic content and antioxidant activities of EWEDL and EEDL measured by the three different assays.
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