The study on the extraction method of indirubin from Indigo Naturalis.

OBJECTIVE: To discuss how to extract the indirubin of the higher purity from Indigo Naturalis. METHODS: After extracting the indirubin from Indigo Naturalis by acetic ether, compare the separation effect of the extract in Si gel column with that in alumina column. RESULTS: The indirubin in Indigo Naturalis by Si gel column chromatography is chosen. The purity of indirubin is 98.3% after Si gel column chromatography. CONCLUSION: The indiruhbin of the higher purity was attained by the simple experimental method.