Mg(2+) enhanced the scavenging activity of (+)-catechin and quercetin against the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH˙), while Al(3+) decreased their activity. Such effects of Mg(2+) and Al(3+) were not observed for kaempferol. Na(+) and Ca(2+) with large ionic radii showed little effect on the DPPH˙-scavenging activity of these three flavonoids.

The antioxidant activity, contents of total phenolics and flavonoids were quantified in the methanolic extracts of four Ulva species(U.clathrata,U.linza,U.flexuosa and U.intestinalis) grown at different parts of northern coasts of the Persian Gulf in south of Iran.The seaweeds were collected from Dayyer,Taheri and Northern Ouli coasts in April 2011. Methanolic extracts of the seaweeds were asse...

Protein isolates of pumpkin (Cucurbita pepo L) seeds were hydrolyzed by acid protease to prepare antioxidative peptides. The hydrolysis conditions were optimized through Box-Behnken experimental design combined with response surface method (RSM). The second-order model, developed for the DPPH radical scavenging activity of pumpkin seed hydrolysates, showed good fit with the experiment data with...

The antioxidant activities of the petroleum ether, ethyl acetate, n-BuOH and water extract fractions from Dracaena cambodiana Pierre ex Gagnep were evaluated in this study. The ethyl acetate fraction contained the highest amount of total phenolics and total flavonoids, and showed the greatest DPPH˙, ABTS+ and Superoxide anion radical-scavenging capacities. The DPPH˙, ABTS+ and Superoxide anion ...

The antioxidant activity, contents of total phenolics and flavonoids were quantified in the methanolic extracts of four Ulva species(U.clathrata,U.linza,U.flexuosa and U.intestinalis) grown at different parts of northern coasts of the Persian Gulf in south of Iran.The seaweeds were collected from Dayyer,Taheri and Northern Ouli coasts in April 2011. Methanolic extracts of the seaweeds were asse...

Genista species are sources of antioxidant phenolic compounds such as O- and C-glycosylflavonoids and isoflavonoids. A combination of a DPPH scavenging assay with HPTLC-MS, a fast and efficient method for identification of bioactive compounds, has been applied for evaluation of the radical scavenging activity of metabolites from Genista saharae Coss. & Dur. Different organs collected at vari...

The aim of this study is to examine possible antioxidant and antiproliferative activities of the different extracts from sweet potato (Ipomoea batatas [L.] Lam ‘Tainong 57’) organs. DPPH staining, total phenolic compounds and flavonoid content, DPPH radical, reducing power method, FTC method, and cell proliferation were all employed. In the DPPH staining, ethanol extract of vein had the highest...

The aim of this study was to determine aldose reductase (AR) inhibitory activity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of compounds from Agrimonia pilosa Ledeb (AP). We isolated agrimoniin (AM), four flavonoid glucosides and two flavonoid glucuronides from the n-butanol fraction of AP 50% methanol extract. In addition to isolated compounds, the AR-inhibitory ...

Leaf of Eucommia ulmoides Oliver (EU) is a Traditional Chinese Medicine and a functional food in China. Antioxidant contents of EU leaves, which were collected monthly during the period of May-October in three years, were determined. Samples' antioxidant capacity was characterized by DPPH radical scavenging activity, hydroxyl radical scavenging activity, ferrous chelating ability, and antioxida...

the antibacterial and antioxidant activities of methanol and acetone extracts of three marine algae, including hypnea hamulosa, gracilaria corticata and enteromorpha intestinalis wereinvestigated.antioxidant activities were determined by means of total antioxidant capacity, total phenolic compounds, dpph radical scavenging activity and ferric reducing antioxidant power. antibacterial activity w...