Isolation of antioxidant compound from therapeutic agent for hepatitis B viral infection

Abstract

A compound showing an antioxidant activity was isolated by methods including Superose 6 HR 10/30 gel filtration and NH2-HPLC and DEAE-5PW HPLC from a natural product currently using as a traditional oriental therapeutic agent. The isolated compound showed an antioxidant activity in the molybdophosphoric acid reduction assay, the peroxidase inhibition assay and EDTA-Fe3+ dependent peroxidation assay. The molecular weight of the compound was estimated to be smaller than 300 by gel filtration. The compound showed a high solubility in water but was relatively insoluble in organic solvents such as ethanol, butanol, propanol, chloroform, benzene and ether. The functional group of this compound seemed to contain an amino group as judged by the positive ninhydrin reaction.