抄録
During the cold extraction of rutin from the Chinese crude drug, Flos Sophorae japonicae, with aqueous solution of borax, it was found that extraction at5-10° yielded rutin while that at 37° yielded quercetin. Pretreatment of the drug by heating at 80-85° for 3 hours resulted in the yield of rutin even by extraction at 37°. The cold extract of Flos Sophorae japonicae was then applied to rutin at 37° by which quercetin was obtained. The same treatment with solution of rutin by the addition of borax gave quercetin from rutin. This decomposition does not occur if the cold extract of the drug is applied at 5-10° or heated at 100° for one hour. Examination of the sugars obtained by the decomposition showed them to be glucose and rhamnose but no rutinose was detected. From these results, it has been clarified that a group of glucosidase is present in Flos Sophorae japonicae which decomposes rutin to quercetin, glucose and rhamnose, the enzymatic reaction of which is not obstructed by the presence of an excessive amount of borax.
