Flavan

Flavan is a type of polyphenol, specifically a flavonoid, that is found in various plant species. It is one of the most common and widespread groups of plant metabolites and is important for plant growth and development. Flavans are also known for their potential health benefits in humans, including anti-inflammatory, anti-cancer, and anti-oxidant effects.

Structure and Classification

Flavans are characterized by a 15-carbon skeleton, which consists of two phenyl groups and a heterocyclic ring. This carbon structure can be abbreviated C6-C3-C6. Based on the variation in the heterocyclic ring, flavans can be classified into several types, including flavan-3-ols, flavan-4-ols, and flavan-3,4-diols.

Biosynthesis

The biosynthesis of flavans is part of the larger phenylpropanoid pathway in plants. This pathway begins with the amino acid phenylalanine, which is converted into cinnamic acid by the enzyme phenylalanine ammonia lyase (PAL). Cinnamic acid is then converted into p-coumaric acid by cinnamate 4-hydroxylase (C4H), and p-coumaric acid is converted into chalcone by chalcone synthase (CHS). Chalcone is the precursor to all flavonoids, including flavans.

Health Benefits

Flavans have been studied for their potential health benefits. They have been found to have anti-inflammatory, anti-cancer, and anti-oxidant effects. For example, flavan-3-ols are the main type of flavonoid found in green tea, and they have been associated with a reduced risk of heart disease and cancer. However, more research is needed to fully understand the health benefits of flavans and how they work in the body.

See Also

• Flavonoid
• Polyphenol
• Phenylpropanoid pathway
• Green tea