Antioxidant sensor, methods and compositions

Abstract

The present invention includes an apparatus and method for detecting directly the antioxidant activity of both lipophilic and lipophobic anti-oxidants that uses an oxygen radical sensitive sensor in fluid communication with a sample in a solvent / water / surfactant mixture; wherein the oxygen radical sensitive sensor concurrently detects both lipophilic and lipophobic anti-oxidants in the solvent / water / surfactant mixture.

Description

FIELD OF THE INVENTION [0001] The present invention relates in general to the field of antioxidant sensors, and more particularly, to antioxidant sensors and methods that directly measure both hydrophilic and hydrophobic anti-oxidants. BACKGROUND OF THE INVENTION [0002] This application claims priority to, and is a continuation-in-part of, U.S. patent application Ser. No. 10 / 648,047, filed Aug. 26, 2004. Without limiting the scope of the invention, its background is described in connection with antioxidant sensor technology and methods for detection. [0003] Biological systems have developed antioxidant systems to combat the effects of radicals and other pro-oxidative species. An antioxidant is any substance that significantly delays or prevents oxidation of an oxidizable substrate when present at low concentrations compared to that of the oxidizable substrate. There are enzymes that are antioxidants, such as superoxide dismutase and catalase, which are coded for by many organisms. S...

AI Technical Summary

Benefits of technology

[0027] The present invention overcomes the limitations in prior art detectors and methods by using a rapid, inexpensive and direct detection system. To address these limitations, the present inventors developed the Oxygen Radical Absorbance Capacity-Oxygen (ORAC(o)) apparatus and method disclosed herein. Using the ORAC(o) apparatus, the present inventors were able to measure, for the first time, the effect of both the effect of both lipophilic and lipophobic anti-oxidants on dissolved oxygen levels, concurrently and in real-time. Using the ORAC(o) assay, the inventors were also able to develop a synergistic anti-oxidant composition, which may be used alone or in combination with one or more anti-oxidant potentiators.

[0039] Flavonoids like quercetin have recently been shown to increase the transcription of the heavy subunit of the rate-limiting enzyme in glutathione synthesis, gamma-glutamylcysteine synthetase, through the gene's antioxidant responsive elements. The increased transcription is subsequently translated in increased intracellular levels of reduced (active) glutathione in tissue culture cells. Quercetin is a major component of red wine, grape skin, and onions. Studies of quercetin from red wine, grape skin, and onions suggest beneficial effects upon health. Quercetin has been shown to be well absorbed by humans. One study showed that all ingested quercetin was metabolized two hours following a meal (European Research on Functional Effects of Dietary Antioxidants, Sep. 25-28, 2002, Cambridge, UK). Upon finding substantially decreased LDL oxidation in subjects consuming moderate amounts of red wine, researchers asserted that the protective effects could very likely be attributed to the activity of quercetin and its metabolites. Quercetin has also been shown to enhance the stability of erythrocytes.

[0042] Other potentiators of anti-oxidant activity include natural extracts, such as grape seed extract and green tea extract. In one study, green tea exhibited potent antimutagenic activity in vitro and inhibited the development of carcinogen-induced preneoplastic lesions in the rat colon. Green tea also significantly inhibited the formation of intestinal polyps. Therefore, the present inventors combined not only a synergistic combination of purified and isolated anti-oxidants from natural sources, such as quercetin and mixed tocopherols, but further added potentiators that increased the detectable anti-oxidant activity of these agents.

Problems solved by technology

Fluorescence from the sample, therefore, can skew the results of an assay based on fluorescence.

Lack of activity from such a combination with mixed tocopherols and saturation problems are absent from the ORAC(o) method since the concentration of sample is more dilute and since the solvent for the sample contains acetone, water, and a detergent for solubilizing all components of a sample.

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