Study On Avilamycin Rational Screening And Fermentation Process Optimization

Avilamycin, a kind of orthosomycin antibiotics ,is a new type of digestive enhancer.The development of the product has the good economic and social performance for it's effective safety and low rudimentality.In this paper, we improve production of Avilamycin by avilamycin rational screening and optimization of fermentation processs.According to the biosythesis pathway and the metabolic regulation of avilamycin,strain improvement was performed by mutation and rational screening to improve the productivity.Through treatment by rational screening and mutagens such as UV,microwave and HNO2 etc,Avilamycin high-yeild strain TN-29 was obtained. Productivity of strain TN-29 reached 65u/mL,which was 2.7-times higher than that of the original of strain Streptomyces Viridochromogenes A.S4.126(TN-27).Subculture test indicated that the hereditary character of strain TN-29 was of stability.The seed medium was optimized by orthogonal experiments;the spore time and inoculum's effect on seed was studied by single experiments.The optimal medium is 2% of peptone, 3.2% of bean cake power, 1.4% of mannite,0.5% of glucose,0.64% of ammonium sulfate,0.0005% of MgSO4, 0.5% of NaCl.When spore time is 84h and spore inoculum is 1.95×109/mL,the DNA concentration of seed was maximized. The DNA concentration of seed was 0.693g/ml.We investigated fermentation process ,optimized the fermentation medium and the culture conditions respectively by full factorial design experiment ,the steepest ascent search experiment , response surface methodology and single experiments respectively. The optimal medium is 3.61% of bean cake power, 2.99% of mannite ,0.5% of glucose, 0.64% of...