α-Viniferin and caraphenol A, the two oligostilbenes, have the sole difference of the presence or absence of an exocyclic double bond at the π-π conjugative site. In this study, the antioxidant capacity and relevant mechanisms for α-viniferin and caraphenol A were comparatively explored using spectrophotometry, UV-visible spectral analysis, and electrospray ionization quadrupole time-of-flight ...

Supercritical carbon dioxide (SC-CO(2)) extraction of bioactive compounds including flavonoids and phenolics from Ampelopsis grossedentata stems was carried out. Extraction parameters such as pressure, temperature, dynamic time and modifier, were optimized using an orthogonal array design of L(9) (3(4)), and antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl ...

The role of epidermal growth factor in the regulation of the proteolytic and RBC cytolytic activity of the A431 cancer cell line has been evaluated using our previously described gelatin/polyacrylamide electrophoretic assay and tumor-induced RBC cytolysis assay, respectively. A431 cells maintained in 10% fetal bovine serum were actively cytolytic for RBC (release index, 53.0 ±2.9%), whereas se...

Purpose: To evaluate the phytochemical profile as well as in vitro antioxidant, iron-chelating, and antiglucosidase activities of Typha domingensis Pers. (Typhaceae) Methods: Total polyphenols, flavonoids, hydroxycinnamic acids, and pro-anthocyanidins in the respective aqueous extracts of male and female flowers, and fruit of T. domingensis were determined by established procedures. Antioxidant...

Rutin is a phenolic compound and found in many plant species. Its name is derived from Ruta graveolens a plant that contain this compound. Rutin has many health benefits like it inhibits platelet aggregation, inflammation, hemorrhoid development etc. It is also used in dietary supplements of human beings for its health benefits. Therefore, this study was planned to investigate its other medicin...

We report a new single-reagent colorimetric assay for the determination of calcium in serum. The assay is based on a novel chromogenic tetracarboxylic acid chelating agent. The method has several advantages over the o-cresolphthalein complexone (CPC) method, including improved linearity, better accuracy, increased stability, and lower working pH (9.0). The calibration curve for the assay is lin...

The study tried to explore the role of sugar-residues and mechanisms of phenolic phenylpropanoid antioxidants. Acteoside, along with its apioside forsythoside B and rhamnoside poliumoside, were comparatively investigated using various antioxidant assays. In three electron-transfer (ET)-based assays (FRAP, CUPRAC, PTIO•-scavenging at pH 4.5), the relative antioxidant levels roughly ruled as: act...

Sodium pyrithione and zinc pyrithione (NaPT and ZnPT, respectively) are widely used as cosmetic preservatives and metal chelating agents. They are commonly assayed using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). However, a simple quantitative colorimetric assay has not been previously reported for these compounds. This paper describes the development of ...

bridged bithiazoles (5,5'-ethylene-4,4'-bithiazoles) are synthesized as a good chelating agent.

this study investigated single-step extraction of heavy metals from contaminated sedimentscollected in the port of cádiz. experimental tests of washing with an aqueous solution of a chelating agent wereperformed at selected solid/liquid (s/l) ratios. two chelating agents were chosen: 0.3 m edta(ph 3.8 and 8)and sodium citrate (1 m). the objective of the tests was to investigate extractive decon...