Polyphenols

Polyphenols Polyphenols are a large number of compounds with one or more aromatic rings and also there are one or more hydroxyl groups on the rings. They are the most abundant secondary metabolites found in plants. The structures of more than 8,000 phenolic are presently known, including simple molecules like phenolic acids and highly polymerized compounds like tannin. They are broadly distributed in all plant organs and are therefore an essential part of the human diet. Polyphenols are widespread components of plant foods (cereals, vegetables, fruits, olive, chocolate and so on) and beverages (coffee, tea, beer, wine and so on).

Phenolics partially contribute to the organoleptic properties of plant foods. For example, phenolics in fruit and fruit juices can interact with the glycoprotein in saliva and are responsible for the bitterness and astringency. Anthocyanins, also known as flavonoids, contribute to the red, blue, orange and purple colors of many fruits and vegetables like apples, berries, oranges and onions.

What’s more, as the most important compounds contributing to differences of flavor and color among white and red wines, phenolics play an important role in the preservation, maturation and aging of white and red wines.

Despite widely distributed in plant kingdom, the health effects of polyphenols attract the attention of nutritionists only in recent years. Because of their abundance in the diet, their potent antioxidant properties, and their significant effects in the prevention of a series of oxidative stress associated diseases like atherosclerosis, neurodegenerative diseases, more and more researchers become interested in polyphenols. Both epidemiologic data and in vitro and in vivo research report indicate the preventive effects of polyphenols. Therefore, it is widely recommend taking food containing more polyphenols. What’s more, it is found that polyphenols regulate the activity of a large number of enzyme and cell receptors.