The purpose of this study was to analyze polyphenol rich beverages (vitamin enhanced waters (VEWs), fruit juices and berry juices) to determine free polyphenol concentrations and free polyphenols per Calorie based on a serving size. The Folin-Ciocalteu reagent was used in a colorimetric assay based on a catechin standard. Fruit and berry juices contained, on average, more than eight-times the c...

A novel polymeric material with antioxidant properties and suitable for ophthalmic application was synthesized by free radical grafting reaction between 2-hydroxyethyl methacrylate and quercetin. The presence of quercetin in the polymeric chain was confirmed by FT-IR and UV-Vis analyses, while an estimation of the amount of quercetin bound per gram of polymer was obtained by the Folin-Ciocalteu...

In the current study, changes in health-promoting substances (phenolics and flavonoids) and antioxidant activity of carrot and mango beverages during storage at 25 and 35°C for 30, 60 and 90 days were investigated. The total phenolic content was determined using Folin–Ciocalteu method. The antioxidant activity was based on the evaluation of free–radical scavenging activity (FRSA) using DPPH rad...

• Today, there are a number of methods available to quantify the phenolic compounds in wines. However, all seem to have some kind of limitation that prevents them from becoming widespread in the winery lab. For example, the Folin-Ciocalteau method is unable to distinguish tannins from polymeric pigments. The Glories method that uses DMCA staining (dimethylcinnamaldehyde) is sample -dependent. A...

The aim of this work was to compare determination of quercetin concentration using HPLCUV/VIS method with antioxidant properties of selected red wines. Typical Slovenian wine varieties like “Merlot”, “Refošk”, “Barbera”, “Cabernet Sauvignon”, “Teran”, “Blue Pinot” and “Blue Frankish” were chosen. We applied the conventional Folin-Ciocalteu spectrophotometric method for determination of the tota...

Photoacoustic (PA) spectroscopy in the ultraviolet and visible was demonstrated to be a suitable tool for direct determination of total phenolic content in red sorghum flours. The PA spectra obtained feature two characteristic peaks: the first centered at 285 nm is due to the aromatic amino acids, while the second one at 335 nm is associated with the total phenolic content. The outcome of the P...

Antioxidant properties of the principal biogenic amines were determined in vitro by four analytical methods—Folin Ciocalteu, DPPH, enzymatic and inhibition of lipid peroxidation—in order to avoid possible measuring-method linked mistakes. Different results are obtained, depending on the parameters that each of them measures. The combination of the data indicates that all examined amines show an...

In the present study experiments were carried out to determine the total phenolic content and their comparative antioxidant activities in relation to phenol content employing Folin-ciocalteu, DPPH, and ABTS assays of the different solvent extracts of the plant S. macrosperma. It was found that on an average, the plant extract with higher levels of phenol content had higher antioxidant activity....

The inhibitors may potentially be used for multiple therapeutic application in viral, bacterial, fungal disease and physiological disorder. In traditional Indian medicine system cassia tora is reportedly effective in treatment of skin and gastrointestinal disorder. The present work describe the isolation extraction purification characterization of trypsin inhibitor from cassia tora seeds. Purif...