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...

Aiming at the exploration of herbal use by society, crude extracts of the seeds of some commonly used medicinal plants (Vitis vinifera, Tamarindus indica and Glycin max) were screened for their free radical scavenging properties using ascorbic acid as standard antioxidant. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The overall antioxi...

free radicals involved in a number of diseases due to the oxidative damage to dna, lipids, and proteins and which can result in failure of cellular functions. dried plant bulbs and leaves methanolic and ethanolic extracts were prepared. total antioxidant activities of the methanolic extracts of romulea ramiflora and gagea fibrosa were determined using β-caroten-linoleic acid assay. romulea-bulb...

The influence of both acidic and basic hydrolysis on the yield, total phenolic content and antioxidative capacity of methanolic extract of germinated brown rice (GBR) was studied. Total phenolic content (TPC), total flavonoid content (TFC), 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation scavenging, and ferri...

Introduction: Rosa damascena mill L., well-known as Rose, has numerous pharmacological properties including antioxidant, antitussive, relaxant effect on tracheal chains, hypnotic, antibacterial and anti-HIV. Objective: The objective of the present study was to evaluate antioxidant and free radical scavenging activity of various extracts of Rose flower petals. Methods: Chloroform, acetone, ethan...

Different studies have demonstrated that the bioactivity of hydroxyflavones is due to their antioxidant and free radical scavenging activity. Recently, most interest has been devoted to structure-activity relationships; however, the main problems encountered in these studies are the low solubility of some hydroxyflavones in aqueous solution and the pro-oxidant character of the hydroxyl group at...

A method for correctly assessing hydroxyl radical scavenging activity of antioxidative chemicals and/or biological compounds/materials was proposed. This method can simultaneously assess two factors, i.e. hydroxyl radical-scavenging and 5,5-dimethyl-2-hydroxy-1-pyrrolidine-N-oxide (hydroxyl radical adduct of 5,5-dimethyl-1-pyrroline-N-oxide)-reducing ability, as antioxidative properties. In thi...

Rice straw was separated into four parts: the upper, middle, and lower parts of the stem, and the leaf. They were treated with subcritical water at 140 to 260 °C. The yield, carbohydrate, protein, and phenolic contents were obtained as well as the UV-Vis absorption spectra and the radical scavenging activity of the extracts. The extracts obtained from the stem parts had almost the same characte...

In this study, sulfated low molecular-weight Tremella fuciformis polysaccharides (SLTP) with different sulfate contents were synthesized and their antioxidant activities, including superoxide anion radical, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical and hydroxyl radical scavenging activities were investigated. The results indicated that, compared to natural Tremella fuciformis polysaccharide...

In the present study, coarse powder of Scindapsus officinalis (Roxb.) Schott. fruit was extracted successively using hexane, chloroform, ethyl acetate and 50% ethanol. The ethyl acetate and 50% ethanolic extracts were investigated for its antioxidant activity by using nitric oxide and DPPH radical scavenging methods. The IC value was also calculated. Ascorbic acid was used as standard. Both the...