At present, it is widely-known that free radicals are the causes of illness such as cancers, coronary heart disease, Alzheimer’s disease and aging. One method of protection from free radical is the consumption of antioxidant-containing foods or herbs. Several analytical methods have been used for qualitative and quantitative determination of antioxidants. This project aimed to evaluate antioxid...

Free radicals are atoms or molecules with unpaired electrons. Many diseases are caused by free radicals. Normally, free radical formation is controlled naturally by various beneficial compounds known as antioxidants. Several analytical methods have been used for qualitative and quantitative determination of antioxidants, and each has its own specificity. This project aimed to evaluate antioxida...

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...

Radical scavenging and antioxidant activities of nine flavonoids previously isolated from the aerial parts of Chenopodium bonus-henricus L. were established using DPPH and ABTS free radicals as well as inhibition of lipid peroxidation in a linoleic acid system by the ferric thiocyanate method. Patuletin glycosides, compounds 1, 2 and 7 showed the highest DPPH (85.78%, 85.59%, 86.07%) and ABTS a...

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 Folin- Ciocalteu Reagent (FCR); antioxidant activity of methanolic extracts were examined by DPPH (2,2diphenyl- 1- picrylhydrazyl), FRAP (ferric reducing antioxidant pow...

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...

The in vitro antioxidant activities of eight 3-carboxycoumarin derivatives were assayed by the quantitative 1,1-diphenyl-2-picrylhydrazil (DPPH•) radical scavenging activity method. 3-Acetyl-6-hydroxy-2H-1-benzopyran-2-one (C1) and ethyl 6-hydroxy-2-oxo-2H-1-benzopyran-3-carboxylate (C2) presented the best radical-scavenging activity. A quantitative structure-activity relationship (QSAR) study ...

MARINOVA, G. and V. BATCHVAROV, 2011. Evaluation of the methods for determination of the free radical scavenging activity by DPPH. Bulg. J. Agric. Sci., 17: 11-24 The survey of the methods for determination of free radical scavenging activity by DPPH has been done. The differences between methods conditions and their evaluation are presented. It was determined the effect of methods conditions b...

Thirteen polyphenolics were isolated from fresh pods of Caesalpinia pulcherrima using various methods of column chromatography. The structures of these polyphenolics were elucidated as gallic acid (1), methyl gallate (2), 6-O-galloyl-d-glucoside (3), methyl 6-O-galloyl-β-d-glucoside (4), methyl 3,6-di-O-galloyl-α-d-glucopyranoside (5), gentisic acid 5-O-α-d-(6'-O-galloyl)glucopyranoside (6), gu...

Eichhornia crassipes (Mart.) Solms possess many antioxidants like glutathione, ascorbic acid etc. Two skin creams of the ethyl acetate extract of E.crassipes were evaluated for its antiageing efficacy by DNA damage inhibition assay and DPPH radical scavenging assay. The DNA damage inhibition and DPPH radical scavenging ability offered by the skin creams increased with increase in concentration ...