Coumaryl tartaric acid

R H, tranr-p-coumaryl tartaric acid (pCT) R OH, tranr-caffeyl tartaric acid (CT)... 

For different Vitis vinifera varieties, differences of phenols in the juice are mainly quantitative, and caffeyl tartaric acid (denominated caftaric acid, CTA) always prevails on p-coumaryl tartaric (coutaric acid, p-CuTA) and ferulyl tartaric (fertaric acid, FTA) acids. In the skins, the principal cinnamic acid is CTA, or alternatively p-CuTA, while FTA... 

In some fruits, PPOs use other phenolic substrates for example a relative of DOPA, 3,4-dihy-droxyphenylethylamine (dopamine), is the major substrate in bananas and DOPA is the natural substrate in the leaves of broad beans. The grape PPO acts on p-coumaryl and caffeoyl-tartaric (caftaric) acids while dates contain an unusual combination of diphenol oxidase substrates including a range of caffeoyl-shikimic acids these are analogous to the ubiquitous isomers of chlorogenic acid [45],... 

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