Of Antibiotics 3 - 0 - Isobutyrylkinamycin C and 4 - Deacetyl - 4 - O - Is Obutyrylkina - Mycin C , New Antibiotics

During the course of a screening program for antibiotics produced by a Saccharothrix, two new kinamycins 1 and 2 have been isolated from cultured broth of strain MI293-N4. They inhibit the growth of Gram-positive bacteria and neoplastic cells. This paper describes the production, isolation, purification and the structure elucidation of the antibiotics. Some physicochemical properties and biological activities of these compoundsare also reported. The strain was cultured at 27°C for 96 hours on a rotatory shaker (180 rpm) in 500-ml Erlenmeyer flasks containing 110ml of medium: Potato starch 3.0%, corn steep liquor 0.5%, yeast extract (Oriental) 0.2%, toast soya 1.5%, NaCl 0.3%, MgSO4-7H2O 0.05%, CaCO3 0.3% and CoCl2-6H2O 0.001% in deionized water. After centrifuging the cultured broth (10 liters), the mycelial cake was extracted with methanol and the extract was concentrated. The concentrate and supernatant were combined and 467