Extraction and purification of urushiol from botanical sources

摘要

The disclosure relates to methods for preparing urushiol from plants including, for example, poison ivy or poison oak. The methods include extraction of plant material using a primary organic solvent more polar than ethanol, followed by a solvent extraction using substantially immiscible solvents having substantially different polarities, such as hexane and acetonitrile. The method can include further purification, such as by fractionation of solvent-extracted materials using a thiazole-derivatized silica gel chromatography medium. The extracts thus generated can exhibit greater purity, higher concentration, and greater stability than extracts made using previously-known methods. The extracts can be particularly suitable for use in immunotherapeutic methods, such as desensitizing individuals who normally develop allergic contact dermatitis attributable to poison ivy or poison oak.

主权项

1. A method for extracting urushiol from a plant, the method comprising contacting the plant and a primary organic solvent that is more polar than ethanol for a period of time and thereafter separating the plant from the primary solvent to yield a liquid initial extract; removing the primary solvent from the initial extract to yield a crude extract; extracting the crude extract with a mixture of first and second solvents, the first and second solvents being immiscible and the first solvent being more polar than the second solvent; and recovering urushiol from the first solvent.