Moutan cortex, a widely used traditional Chinese medicine for the treatment of various diseases, is the root bark of Peaonia suffruticosa Andrews (Paeoniaceae). In this study, the crude polysaccharides (CPS), paeonol and the crude total glycosides (CTG) of moutan cortex were extracted by the multiple-stage extraction. CPS was extracted by water, paeonol was distilled by steam distillation metho...

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...

The antioxidant activity of defatted ethanolic extract of the leaves of Blumea mollis were studied for its free radical scavenging property on different in vitro antioxidant models like DPPH radical, hydroxyl radical, nitric oxide radical scavenging activity, reducing power, superoxide anion radical scavenging activity were analyzed. The extract showed free radical scavenging property in dose-d...

In this study, quantitative structure activity relationship (QSAR) models for the antioxidant activity of polysaccharides were developed with 50% effective concentration (EC50) as the dependent variable. To establish optimum QSAR models, multiple linear regressions (MLR), support vector machines (SVM) and artificial neural networks (ANN) were used, and 11 molecular descriptors were selected. Th...

Argentine croaker (Umbrina canosai) and chicken (Gallus domesticus) bones were hydrolyzed with different proteases (Flavourzyme, "-Chymotrypsin and Trypsin) in order to obtain peptides whit antioxidant activity. The hydrolysates showed different degrees of hydrolysis and antioxidant activity. The antioxidant power of the hydrolysates was evaluated through inhibition of the peroxidation of linol...

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...

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...

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...

A pectin (CAP) was extracted from the husk of Cicer arietinum L. Monosaccharide analysis of CAP revealed the dominance of galacturonic acid and smaller amounts of galactose, arabinose, rhamnose, glucose, xylose and mannose. Viscosimetric analysis showed that the intrinsic viscosity ([η]) and the molecular weight (MW) of CAP were 296 mL/g and 105 kDa, respectively. The degree of esterification (...

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...