Studies on cochleamycins, novel antitumor antibiotics. I. Taxonomy, production, isolation and biological activities

Novel antitumor antibiotics cochleamycins A, A2, B and B2 (Fig. 1) were isolated from the culture broth of Streptomyces sp. DT136. They were purified by column chromatography on silica gel, reversed phase HPLC and then isolated as colorless powder. Cochleamycins showed growth inhibition against tumor cells in vitro.