The 2,2'-diphenyl-1-picrylhydrazyl (DPPH(•)) method is commonly applied for the estimation of antioxidant activity of single compounds and plant extracts. In this method, the amount of disappeared DPPH(•) in the examined system, determined spectrophotometrically, is a measure of the antioxidative (hydrogen-donating) activity of compounds. The present paper discusses the influence of buffer comp...

Purpose: To improve the aqueous solubility of phloridzin by complexing it with hydroxypropyl-βcyclodextrin (HP-β-CD). Methods: The complex of phloridzin with HP-β-CD was prepared by freeze-drying method. The physicochemical properties of the complex were investigated by ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), differential scanning calorimetry (DSC) and x-ray diffracto...

The group of 21 novel semi-synthetic derivatives of quercetin was screened for the antiradical efficiency in a DPPH assay. The initial fast absorbance decrease of DPPH, corresponding to the transfer of the most labile H atoms, was followed by a much slower absorbance decline representing the residual antiradical activity of the antioxidant degradation products. Initial velocity of DPPH decolori...

Antioxidant activities and Anti-inflammatory activity of the extracts were evaluated by a 1, 1-diphenyl, 2-picrylhydrazyl free radical (DPPH), 2, 2’-Azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and antilipoxygenase assay for the water extraction of Thespesia lampas Dalz & Gibs. Ascorbic acid, gallic acid and indomethacin were used as reference standards for DPPH, ABTS and anti-lipox...

This paper presents the findings of electron paramagnetic resonance (EPR) spectroscopy experiments conducted on two different samples: 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Manganese Chloride (MnCl2) dissolved in H2O. The were at Dr. D. Petasis EPR lab located Allegheny College, Meadville, PA, USA. A Varian X-Band spectrometer was utilized for analysis absorption spectra. primary objective t...

Radical Scavenging capacity Abstract: In-vitro antioxidant activity of methanolic extract of Rhinacanthus nasutus leaves was determined by DPPH free radical scavenging assay and Reducing Power assays. Ascorbic acid was used as standard and positive control for both the analysis. All the analysis was made with the use of UV-Visible Spectrophotometer. The methanolic extract of Rhinacanthus nasutu...

Hemp protein hydrolysates with various yields of trichloroacetic acid (TCA)-soluble peptides (Ysp) and surface hydrophobicity (Ho) were obtained by Neutrase ® hydrolysis from hemp protein isolate (HPI). The peptide profiles, amino acid composition and antioxidant activities (DPPH radical scavenging ability, reducing power and Fe chelating ability) of the hydrolysates, obtained at 60–240 min, we...