Page 112 - phytochemistry II -pharmD general

suggests a role in the prevention of neurodegenerative diseases and
diabetes mellitus. Significant progress has been made in the field of
cardiovascular diseases, and today it is well established that some
polyphenols, administered as supplements or with food, do improve health
status, as indicated by several biomarkers closely associated with
cardiovascular risk reported that epidemiologic studies tend to confirm the
protective effects of polyphenol consumption against cardiovascular
diseases.

Flavonoids comprise the most common group of plant polyphenols. They
promote antioxidant activity, cellular health and normal tissue growth and
renewal throughout the body. They also work with vitamin C to reduce
oxidative stress for the water-based portion of the cell and may slow down
some of the effects of aging. There are more than 4,000 unique flavonoids
and they are most effective when several types are consumed together.
Food sources include cranberries, kale, beets, berries, red and black grapes,
oranges, lemons, grapefruits and green tea.

The chemistry of antioxidants

The major antioxidants currently used in foods are monohydroxy or
polyhydroxy phenol compounds with various ring substitutions. These
compounds have low activation energy to donate hydrogen. Hence, the
resulting antioxidants radical does not initiate another free radical due to the
stabilization of the delocalized radical electron. Propagation and initiation of
free radicals chain reaction can be delayed or minimized by the donation of
hydrogen from the antioxidants and metal chelating agent. The resulting
antioxidant free radical is not subject to rapid oxidation due to its stability.

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