METHOD FOR PREPARING A PURIFIED MADDER ROOT EXTRACT

摘要

The invention pertains to a method for preparing a parified madder root extract comprising the steps of providing a madder root extract comprising one or more contaminants selected from rubiadin and lucidin with a pH of at least 8, contacting the extract with a polystyrene-based resin, and recovering an extract from which contaminants selected from rubiadin and lucidin have been removed at least in part. It has been found that by the method according to the invention rubiadin and lucidin can be effectively removed from a madder root extract.