A new dry extract of cascara (Rhamnus purshiana D.C. bark)

Publisher Website
Google Scholar
Abstract
The B.P. method of preparing a dry extract of cascara leads to significant breakdown of O-glycoside links in the active compounds. This is shown to be due to enzyme activity during percolation. A dry extract, containing most of the active glycosides originally present in the bark with no change in glycosylation status, can be prepared using boiling water as extracting solvent. A modification of the chemical assay process is recommended as well as the use of an official standardized extract with upper and lower limits for glycoside content.