Isolation, purification and partial characterization of an active anti-HIV compound from the Chinese medicinal herb viola yedoensis.

The dimethylsulfoxide extract of the Chinese medicinal herb Viola yedoensis demonstrates high inhibitory activity toward HIV-1 in vitro. The corresponding methanol extract also showed inhibitory activity but not as high as the dimethylsulfoxide extract. Anti-HIV activity in the extracts is accompanied by cytotoxicity, and we describe here the separation of the cytotoxic material from the active fraction. We also describe the procedure for isolation, purification, and separation of the active component from crude extracts of V. yedoensis as well as details of its activity against HIV-1. The UV-visible, infrared (IR) and proton nuclear magnetic resonance (NMR) data and certain other characteristics of the active compound are also presented. Initial chemical tests and the proton NMR and IR spectra indicate a high molecular weight sulphonated carbohydrate polymer, and chromatographic evidence suggests an MW between 10,000 and 15,000.