Antioxidant effect of natural phenols

A polyphenol antioxidant is a type of antioxidant containing a polyphenolic substructure. Numbering over 4,000 distinct species, many of these compounds have antioxidant activity in vitro but are unlikely to have antioxidant roles in vivo. Rather, they may affect cell-to-cell signaling, receptor sensitivity, inflammatory enzyme activity or gene regulation.

From about 500 million years ago, freshwater and terrestrial plants slowly optimized the production of “new” endogenous antioxidants, such as ascorbic acid (vitamin C), natural phenols (including flavonoids) and polyphenols, , etc. A few of these appeared more recently, in the last 50–200 million years, in fruits and flowers of angiosperm plants. In fact, the angiosperms (the flowering plants), the dominant type of plant today (and most of their antioxidant pigments) evolved during the late Jurassic period.

The main source of polyphenols is dietary, since they are found in a wide array of -bearing foods. For example, honey; most legumes; fruits such as apples, blackberries, blueberries, cantaloupe, pomegranate, cherries, cranberries, grapes, pears, plums, raspberries, aronia berries, and strawberries; and vegetables such as broccoli, cabbage, celery, onion and parsley are rich in polyphenols. Red wine, chocolate, black tea, white tea, green tea, olive oil and many grains are sources. Ingestion of polyphenols occurs by consuming a wide array of plant foods.

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