High purity carnosic acid from rosemary and sage extracts by PH-controlled precipitation

摘要

A process for the extraction and isolation of concentrated carnosic acid from plant matter of the Labiatae family including contacting the plant matter with a water-miscible solvent to form a plant extract and adjusting the pH of the plant extract to a level between 7 and 10 while adding water in an amount sufficient to cause precipitation of impurities while retaining the carnosic acid salt in solution. The impurities are separated and the remaining aqueous solution is acidified to precipitate a highly purified carnosic acid product which is essentially odorless, flavorless and colorless.