Glucogallin

Glucogallin is chemical compound formed from gallic acid and β-D-glucose. It can be found in oaks species like the North American white oak (Quercus alba), European red oak (Quercus robur) and Amla fruit (Emblica officinalis).

It is formed by a gallate 1-beta-glucosyltransferase (UDP-glucose: gallate glucosyltransferase), an enzyme performing the esterification of two substrates, UDP-glucose and gallate to yield two products, UDP and glucogallin. This enzyme can be found in oak leaf preparations.