An antioxidant is a substance that reduces oxygen damage caused by free radicals, a process known as oxidation.  Recently, antioxidants have received more attention from nutritionists and medical researchers for their potential effects in preventing aging and aging-related disorders such as cardiovascular disease, cancer, and inflammatory disease. These effects are related to the components in naturally occurring substances with antioxidant activity, which is defined as the ability to scavenge excessive amounts of pro-oxidant free radicals in the human body. There is growing interest in measuring and utilizing antioxidants in the food, pharmaceutical, and cosmetic industries.

 

Only a few of our internal enzyme systems can scavenge free radicals, so most antioxidants need to be consumed daily. These include various vitamins, minerals, amino acids, enzymes, polyphenolic compounds (plant phenols or polyphenols, such as found in green tea or grapes) and carotenoids. These antioxidant sources can effectively combat the oxidative stress and damage caused by free radicals. Research also shows that the antioxidant capacity of fruits, vegetables and herbs can be affected by numerous factors. Such factors include genotype (plant genetics differing in varieties of seed stock), growing seasons and location, maturity and post-harvest storage conditions.  Therefore, in order to determine the potential amount of antioxidants in foods and their potential health effects, we need to know the possible interaction of these components and their net contribution to antioxidant activity. This means that a convenient analytical method (test) for a quick measure of antioxidant effectiveness is important.

 

Different tests have been developed to measure the antioxidant activity of various foods and other biological substances. These tests help us to understand the antioxidants’ relative ability to control their respective oxidants. The oxygen-radical absorbance capacity (ORAC) test has become one of the standard methods to measure the antioxidant properties of botanical and biological substances.^1-4 This sensitive and reliable method gives us a way to measure the total antioxidant potential in foods and supplements, both separately and in formulas (combinations).

 

The higher ORAC value of a certain food, typically given as ORAC units, the higher the concentration of antioxidants is in that food.^1-4

 

NOW Foods has just begun to label the ORAC value for its antioxidant products, starting with NOW® VitaBerry Plus+™, a powerful antioxidant supplement providing at least 2,500 ORAC units per serving. VitaBerry Plus+™ contains the carefully dried fruit powders of wild blueberry, cranberry, raspberry, strawberry, prune, tart cherry, bilberry and grape.  Since there is a positive linear correlation between the total antioxidant capacity of foods and the amount of phenolics, anthocyanidins and vitamins they contain, we have developed and validated HPLC (High Performance Liquid Chromatograph) methods for quantitative analysis (testing) of these compounds. Meanwhile, we are establishing and developing ORAC test methods based on numerous published papers to continue to assay the total ORAC value of our antioxidant products. As more consumers know how to use ORAC units as a measure of antioxidant function, more nutraceutical companies will use ORAC values to quantify the antioxidant benefits of their products. NOW is clearly an industry leader in its commitment to quality and functional testing.

 

References:

 

¹  Food Chemistry 91 (2005) 723-729

²  J. Agric. Food Chem 2001,49,4619-4626

³  J. Agric. Food Chem 2002,50,1815

⁴  J. Agric. Food Chem 2005,53,1841-1856