Preparative isolation and purification of anti‐tumor agent ansamitocin P‐3 from fermentation broth of Actinosynnema pretiosum using high‐performance counter‐current chromatography

Ansamitocin P-3 is a potent anti-tumor maytansinoid found in Actinosynnema pretiosum. However, due to the complexity of the fermentation broth of Actinomycete, how to effectively separate ansamitocin P-3 is still a challenge. In this study, both analytical and preparative high-performance counter-current chromatography were successfully used to separate and purify ansamitocin P-3 from fermentation broth. A total of 28.8 mg ansamitocin P-3 with purity of 98.4% was separated from 160 mg crude sample of fermentation broth in less than 80 min with the two-phase solvent system of hexane-ethyl acetate-methanol-water (0.6:1:0.6:1, v/v/v/v). The purity and structural identification were determined by HPLC, (1)H NMR, (13)C NMR and mass spectroscopy.