Hydroxyl and superoxide anion radical scavenging activities of natural source antioxidants using the computerized JES‐FR30 ESR spectrometer system

Abstract

SUMMARYFree radical scavenging activities of water-soluble extracts from some natural sources, health foods, and antioxidant substances were measured using the JES-FR30 JEOL spectrometer. The objective was to develop a standardized method whereby comparison could be made between the radical scavenging activities of complex mixtures.Scavenging of hydroxyl radical was determined using DMPO. Activity was calibrated using a standard material, L-ascorbic acid 2-[3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6yl-hydrogen phosphate] potassium salt (EPC-K1), an analog of vitamin C and vitamin E which is water soluble and stable at room temperature. The order of greatest hydroxyl radical scavenging activity was green tea extract, pine bark extract (Pycnogenol), Ginkgo Biloba extract (EGb 761), a flavonoid blend of several fruit and vegetable extracts (GNLD), and Bio-Normalizer (Sun-O Corp). Activity was determined after treatment of samples with ascorbic acid oxidase. This treatment revealed the presence of ascorbate in some natural extracts and commercial preparations. The pine bark extract was the most heat resistant and had ascorbate-like activity in the preparations.Scavenging of superoxide anion was determined using the spin trap, 5,5-dimethyll-pyrroline-N-oxide (DMPO), and analyzed by comparison with a standard curve made with superoxide dismutase. Comparison of the water solubilized components of natural source antioxidants showed that filtrates fractionated using centrifuge type Millipore filter tubes (M.W.<100,000; M.W.<10,000) also had almost the same SOD-like activity. Samples were also treated with ascorbate oxidase or by heating (100~ for 10rain). The order of activity, from greatest to least, was Ginkgo biloba extract EGb 761, pycnogenol, ~3-catechin, tea and BioNormalizer.

Effect of Herbal Preparation on Heavy Metal (Cadmium) Induced Antioxidant System in Female Wistar Rats

“…There is evidence that indigenous antioxidants may be useful in preventing the deleterious consequences of oxidative stress, and there is increasing interest in the protective biochemical functions of natural antioxidants contained in spices, herbs and medicinal plants [33]. In the present study a significant increase in SOD and catalase activity was observed in the ovaries of 45-day and 65-day age group animals ( Figs.…”

The effect of pycnogenol on lymphatic nodes and adhesion during in a peritoneal adhesion model in rats

“…In our study, in immunohistochemical analyses performed on tissues taken on day 7 to detect oxidative stress using GSTP-1, Glut Red, SOD-1, and CAT, it was found that Pycnogenol statistically increased free oxygen radicals in the tissues. In a study conducted by Noda et al 22 , pycnogenol was reported to be one of the effective free radical scavengers. However, in our study, immunohistochemical analyses revealed that the production of free oxygen radicals increased in the tissue.…”

The flavonoid galangin is an inhibitor of CYP1A1 activity and an agonist/antagonist of the aryl hydrocarbon receptor

“…Flavonoids exert a multiplicity of biochemical actions that are believed to be an important part of the chemopreventive effect of plant-based diets. Various flavonoids are potent antioxidants (Kono et al, 1997;Noda et al, 1997), inhibit lipoxygenase and cyclooxygenase (Mirzoeva and Calder, 1996), affect the activity of several hepatic enzymes involved in activation and detoxification of carcinogens (Canivenc-Lavier et al, 1996), inhibit cellular proliferation (Tsyrlov et al, 1994;Siess et al, 1995;Moon et al, 1998), and induce apoptosis of tumour cells (Csokay et al, 1997). Galangin, a member of the flavonol class of flavonoids, is present in high concentrations in Alpina officinarum (common name: China or India root), which has been used as a spice and as a herbal medicine for a variety of ailments in Asia for centuries.…”