| 摘要 |
PURPOSE:To collect colistin, by cultivating a bacterium belonging to the genus Bacillus capable of producing the titled substance in a medium containing an inorganic phosphoric acid and nitrogen in the form of ammonia in fixed concentrations, forming and accumulating the titled substance in the culture. CONSTITUTION:A strain such as Bacillus polymyxa veriety H-3123, etc. belonging to the genus Bacillus, capable of producing colistin is cultivated in a medium containing 10<-4>-5X10<-2>g/dl calculated as an inorganic phosphoric ion of inorganic phosphate such as potassium phosphate, etc. and 0.02-0.5g/dl nitrogen in the form of ammonia such as ammonium sulfate, ammonium chloride, etc. Starch, maltose, saccharose, etc. are used as a sugar source for the main fermentation medium, the nitrogen source contains ammonium sulfate, ammonium chloride, etc., and the cultivation is carried out aerobically at 20-40 deg.C for 2-3 days. Colistin is collected from the culture by filtration, ion exchange resin treatment, etc. |
