Tuesday, September 28, 2010
Catechin and Epicatechin
We’ve all heard of these two phytochemicals as beneficial components of our favorite foods: tea, wine and chocolate! These molecules are part of a large family called flavonoids. Notice the 3 ring structures in the diagram; this is what makes these two molecules a flavonoid. More specifically, they are flavanols. The -ol just refers to OH group that you see on the lower right portion of the molecule. Anything that has an OH group is considered an alcohol and the name of the molecule typically ends with –ol as does flavanol. The most common alcohol, ethanol, also ends with –ol and catechin can more correctly be called catechol.
Catechin and epicatechin are isomers which mean they have the same molecular formula (count the number of carbons, hydrogens and oxygens!) but have a different structure or arrangement of those atoms. With catechin and epicatechin the difference lies in the OH group we just spoke of. It is below the plane in epicatechin and above the plane in catechin which is indicated by either the dashed or solid line.
The more correct name for catechin is: 3,3’,4’,5,7-pentahydroxyflavan. Another example of why the phrase 'if you can’t pronounce something it isn’t good for you' just isn't true!
Oftentimes catechins will be attached to a sugar molecule and are referred to as O-glycosides. Products that are high in catechins and epicatechins have been found to have protective effects toward heart disease. Newer research has shown that these compounds are protective for the skin, providing photoprotection and improving the appearance and hydration of skin. Tea, both green and black, may also protect against skin cancer. Apparently, flavonoids have the ability to absorb UV light which may make them a useful ingredient in sun screens and other skin care products. These chemicals are a great addition to a skin care product to protect skin.