Fucoxanthin (Fuco) is a characteristic carotenoid of brown seaweeds. In the present study, Fuco and its stereoisomers 9'Z-Fuco, 13Z- and 13'Z-Fuco were extracted from Laminaria japonica Aresch. They were isolated and purified by silica gel column chromatography, Sephadex LH-20, and reversed-phase HPLC. The radical-scavenging activities of the three stereoisomers were evaluated toward 1,1-diphen...

The objective of this study was to evaluate total phenolic content and antioxidant activity of leaf and different parts of fruit (hull, shell, and kernel) of Bene in Ilam province. Total phenolic content was determined with the FolinCiocalteu Reagent (FCR); antioxidant activity of methanolic extracts were examined by DPPH (2,2diphenyl1picrylhydrazyl), FRAP (ferric reducing antioxidant power) an...

In this study, n-butanol fraction (KBF) and aqueous fraction (KAF) isolated from methanol extract of Koelreuteria paniculata Laxm. leaves were evaluated for their antioxidant potential using (ABTS) 2, 2-Azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid), DPPH (2,2-diphenyl-2-picrylhydrazyl) assay, Reducing power assay and Superoxide anion radical scavenging assay. These fractions were also studi...

− A method for simultaneously identifying antioxidative compounds was developed using time-based LC-MS coupled with DPPH assay regardless of the time consuming process. The methanolic extract of Polygonum aviculare (Polygonaceae) showed significant DPPH radical scavenging activity. Time-based DPPH assay for simultaneous identification of active compounds from the extracts of P. aviculare was us...

the plants of the genus salvia synthesize several types of secondary metabolites with antimicrobial, cytotoxic, and radical scavenging activities and are used in the folk medicine of different countries. eleven salvia species including s. aegyptiaca, s. aethiopis, s. atropatana, s. eremophila, s. hypoleuca, s. limbata, s. nemorosa, s. santolinifolia, s. sclarea, s. syriaca, and s. xanthocheila ...

the subject handled in this study is the determination of antioxidant activities of extracts obtained from the urginea maritima (l.) baker plant’s leaves and tubers. extractions which were obtained using various solvents as methanol, ethanol, acetone and benzine. the antioxidant activity of the extracts was determined using β-karotene-linoleic acid system. moreover, the free radical scavenging ...

the hawthorn fruits have been used as food and medicine for centuries. in the present study, pulp and seed extract of crataegus elbursensis rech. f. fruits belonging to the family rosaceae and native of northern part of iran were evaluated for the polyphenol contents, antiradical, antioxidant, and antibacterial activities. the total phenolic, flavonoid, and anthocyanin contents of methanolic pu...

background & aim: free radicals play a crucial role in the development of tissue damage in various human diseases such as cancer, aging, neurodegenerative disease, malaria and arteriosclerosis, and pathological events in living organisms. antioxidants may have an important role in the prevention of these diseases. the aim of this study is to evaluate potency of scavenging of dpph free radic...

A new computational approach for the determination of 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (DPPH-RSA) in food is reported, based on the concept of machine learning. Trolox standard was mix with DPPH at different concentrations to produce different colors from purple to yellow. Artificial neural network (ANN) was trained on a typical set of images of the DPPH radical re...

The free radical 2,2-diphenyl-1-pycrylhydrazyl (DPPH) was tested as a polarising agent for fast dissolution dynamic nuclear polarisation (DNP) NMR spectroscopy. DPPH was found to be reasonably soluble in sulfolane and the optimum concentration for DNP is 20-40 mM depending upon whether short polarisation times or the maximum signal intensity is needed. W-band ESR measurements revealed that the ...