Synthesis of Mono-, Di- and Trigalloyl-ß-D-glucose by /J-Glucogallin-Dependent Galloyltransferases from Oak Leaves
نویسنده
چکیده
/?-Glucogallin, Digalloyl-/?-D-glucose, Trigalloyl-/?-D-glucose, G alloyltransferase, G allotannin Biosynthesis, Quercus robur Cell-free extracts from oak (Quercus robur) leaves were found to contain at least two /?-glucogallin-dependent galloyltransferases. One enzyme catalyzed a rap id exchange o f the galloylm oiety o f /?-glucogallin with free glucose. A second enzym e fraction was show n to form digalloylglucose, utilizing /?-glucogallin both as acyl-donor and acceptor m olecule; in add ition , evidence for the synthesis o f trigalloylglucose was obtained. Both enzym e-system s had th e ir pH -optim um at pH 6 .0 -6 .5 . It is assum ed that these newly described galloyltransferases are involved in the biosynthesis o f gallotannins.
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