Green tea is a type of tea that is made from Camellia sinensis leaves and buds that have not undergone the same withering and oxidation process which is used to make oolong teas and black teas. Green tea originated in China, and since then its production and manufacture has spread to other countries in East Asia.
Gallic acid (also known as 3,4,5-trihydroxybenzoic acid) is a trihydroxybenzoic acid with the formula C6H2(OH)3CO2H. It is classified as a phenolic acid. It is found in gallnuts, sumac, witch hazel, tea leaves, oak bark, and other plants. It is a white solid, although samples are typically brown owing to partial oxidation. Salts and esters of gallic acid are termed "gallates".
Flavonoids are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans.
Flavan-3-ols are a subgroup of flavonoids. They are derivatives of flavans that possess a 2-phenyl-3,4-dihydro-2H-chromen-3-ol skeleton. Flavan-3-ols are structurally diverse and include a range of compounds, such as catechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate, proanthocyanidins, theaflavins, thearubigins. They play a part in plant defense and are present in the majority of plants.
Catechin is a flavan-3-ol, a type of secondary metabolite providing antioxidant roles in plants. It belongs to the subgroup of polyphenols called flavonoids.
Polyphenon is a series of high grade green tea polyphenol extracts manufactured by the Mitsui Norin Co., Ltd. of Japan. The extracts are in part the result of a water based extraction method which begins with green tea leaves, and then involves successive steps which concentrate the catechins thought to be responsible for the health benefits of green tea.
Thearubigins are polymeric polyphenols that are formed during the enzymatic oxidation and condensation of two gallocatechins with the participation of polyphenol oxidases during the fermentation reactions in black tea. Thearubigins are red in colour and are responsible for much of the staining effect of tea. Therefore, a black tea often appears red while a green or white tea has a much clearer appearance. The colour of a black tea, however, is affected by many other factors as well, such as the amount of theaflavins, another oxidized form of polyphenols.
Epigallocatechin gallate (EGCG), also known as epigallocatechin-3-gallate, is the ester of epigallocatechin and gallic acid, and is a type of catechin.
The phenolic content in wine refers to the phenolic compounds—natural phenol and polyphenols—in wine, which include a large group of several hundred chemical compounds that affect the taste, color and mouthfeel of wine. These compounds include phenolic acids, stilbenoids, flavonols, dihydroflavonols, anthocyanins, flavanol monomers (catechins) and flavanol polymers (proanthocyanidins). This large group of natural phenols can be broadly separated into two categories, flavonoids and non-flavonoids. Flavonoids include the anthocyanins and tannins which contribute to the color and mouthfeel of the wine. The non-flavonoids include the stilbenoids such as resveratrol and phenolic acids such as benzoic, caffeic and cinnamic acids.
Prodelphinidin is a name for the polymeric tannins composed of gallocatechin. It yields delphinidin during depolymerisation under oxidative conditions.
The molecular formula C22H18O11 (molar mass: 458.37 g/mol, exact mass: 458.084911) may refer to:
Tricetinidin is an intense red-colored chemical compound belonging to the 3-deoxyanthocyanidins. It can be found in black tea infusions. Tricetinidin, in tea, would be a product of the oxidative degallation of epigallocatechin gallate (EGCG).
Epicatechin gallate (ECG) is a flavan-3-ol, a type of flavonoid, present in green tea. It is also reported in buckwheat and in grape.
Prorobinetidins are a type of condensed tannins formed from robinetinidol. They form robinetinidin when depolymerized under oxidative conditions.
Gallocatechin gallate (GCG) is the ester of gallocatechin and gallic acid and a type of catechin. It is an epimer of epigallocatechin gallate (EGCG).
The phenolic content in tea refers to the phenols and polyphenols, natural plant compounds which are found in tea. These chemical compounds affect the flavor and mouthfeel of tea. Polyphenols in tea include catechins, theaflavins, tannins, and flavonoids.
Sinecatechins is a specific water extract of green tea leaves from Camellia sinensis that is the active ingredient in an ointment approved by the FDA in 2006 as a botanical drug to treat genital warts. Sinecatechins are mostly catechins, 55% of which is epigallocatechin gallate. It was the first botanical drug approved by the US FDA.
Michiyo Tsujimura was a Japanese agricultural scientist and biochemist whose research focused on the components of green tea. She was the first woman in Japan to receive a doctoral degree in agriculture.
Theasinensin A is polyphenol flavonoid from black tea created during fermentation, by oxidation of epigallocatechin gallate.
