Abstract
Rice seeds (paddy) were germinated and cultured on 0.01 to 1 mM pyridoxine (PIN) solution. The added PIN was proved by paper chromatography to be incorporated and transformed into some metabolites of PIN in the seedlings. The main product among them was isolated as a PIN-derivative of colorless powder, mp 167℃, after the treatment of the extract of seedlings by ion-exchange chromatography, gel filtration and charcoaladsorption chromatography. The UV, IR and NMR spectral data on the compound implied that a hexose was bound to the 4- or 5-hydroxymethyl group of PIN. Acid hydrolysis of the compound gave PIN and glucose. It was clarified that glucose was bound to the 5-hydroxymethyl group of PIN from the positive reaction of the compound toward diazotized sulfanilic acid and the negative one to the same reagent under the presence of borate. The configuration of the bound glucose was proved to be β-from the results of hydrolysis with α- or β-glucosidase. The released sugar was oxidized to gluconic acid by the action of D-glucose oxidase, indicating that it was D-glucose. Conclusively, the isolated PIN-derivative was identified as 5'-O-(β-D-glucopyranosyl) pyrioxine.
