Patent ID: 8048914

Claim:
A method for purifying an extract of Tripterygium wilfordii plant material containing triptolide and related compounds, wherein the extract is formed by (a) extracting plant material with aqueous ethanol, and concentrating to obtain a residue; and (b) forming a slurry of this residue in an chlorinated organic solvent; partitioning the slurry with water for a period of about 10 mins-10 hours; and then removing the water; and said purifying comprises the steps of: (c) further partitioning the slurry with an aqueous solution of base, removing the aqueous solution of base, and removing at least a portion of the organic solvent from the slurry; (d) washing the product of step (c) with a lipophilic solvent; and (e) eluting the washed product from step (d) from a silica gel adsorbent.