The present study evaluated the antioxidant potential of 28 coumarin derivatives, using three antioxidant assays: DPPH inhibition, total reducing power and NO inhibition. Out of the tested compounds, the most active DPPH free radicals scavengers were the coumarin hydrazide derivatives. These substances were also the only ones among the investigated derivatives that exhibited a moderate reducing...

The in vitro antimicrobial and antioxidant activities of the exopolysaccharide (EPS) extracted from yoghurt starter were investigated. Antimicrobial activity tests were carried out using disc diffusion methods with Escherichia coli, Staphylococcus aureus and Streptococcus D, Proteus spp and the yeast of Candida albicans. The antioxidant properties were evaluated using the test of DPPH free radi...

The Clitoria ternatea, Solanum nigrum and Aloe vera leaves were extracted serially by the solvents of increasing polarity (petroleum ether, chloroform and ethanol) were tested for their free radical scavenging activity against DPPH. The petroleum ether extracts of Clitoria ternatea, Solanum nigrum and Aloe vera leaves were the most effective scavenging of DPPH. These plant extracts were also an...

The DPPH radical scavenging activity of 2',4',6'-trihydroxy- and 2'-hydroxy-4',6'-dimethoxychalcones carrying a 2,3- and 3,4-dihydroxylated, and 3,4,5-trihydroxylated B-ring was evaluated in alcoholic and non-alcoholic solvents. All test compounds scavenged more than two equivalent of radicals by a possible conversion to the corresponding B-ring quinones and in most cases subsequently underwent...

1,1-Dipehnyl-2-picrylhydrazyl (DPPH) radical scavenging activities were found in the extract of dried leaves of oregano (Origanum vulgare). The water-soluble active ingredients were isolated, and their structures were determined to be 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate and 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl 4-O-methylprotocatechuate by (1)H-, (13)C-NM...

this study aimed to determine biological activity and phytochemical study of scutellaria platystegia (family labiatae). methanolic (meoh) extract of aerial parts of s. platystegia and spe fractions of methanolic extract (specially 20% and 40% methanolic fractions), growing in east-azarbaijan province of iran were found to have radical scavenging activity by dpph (2, 2-diphenyl -1- pycryl hydraz...

in this study, the antioxidant activity and protective effects of purslane seed water-methanolic extract (pswme) in stabilizing soybean oil (sbo) were tested. dpph radical scavenging activity of pswme at different concentrations varied significantly (p< 0.05), ranging from 15.41% to 79.06%. total phenolic content in pswme was 121.09 mg gallic acid equivalent (gae) kg-1 dw. the protective effect...

factors such as oxidative stress and reduced acetylcholine level have been implicated in alzheimer’s disease (ad) pathology and recently there has been a trend towards natural product research to find potential sources of antioxidants and acetylcholinesterase inhibitors in the plants kingdom. centaurea is a genus with about 500 species world wild, many of them have shown to possess biologic act...