| abstract |
A method of preparing substantially pure cannabidiol from plant material comprises obtaining a cannabidiol-containing extract, dissolving it in a solvent to form a solution, removing the insoluble material and evaporating the solvent. The insoluble material is preferably removed by filtration and the solvent is preferably non-polar, in particular pentane, hexane or propyl carbonate. The cannabidiol-containing extract may be a botanical drug substance derived from the plant material. This botanical drug substance may be obtained by solvent extraction of the plant material, particularly by carbon dioxide extraction followed by a secondary extraction step comprising ethanolic precipitation to remove a proportion of the non-target materials. Substantially pure preparations of cannabidiol, having a chromatographic purity of 95 % or greater, are disclosed. The preparations may be white crystalline solids at room temperature. |