Mutation Breeding Of Streptomyces Aureofaciens By Low Energy N~+ Implantation And Its Fermentation Characteristics

Ion beam can be defined as the radiation which was the product of accelerated ions of chemical element by high-energy ion accelerator. The discovery of ion beam induced biological effects paved a new way for genetic modification. In this paper, mutation breeding of Streptomyces aureofaciens by ion beam implantation, which may favor biological effects study of ion beam and expand the applied field of ion beam biotechnology, was dicussed.First of all, Shake-Flask fermentational conditions of high-yielding Streptomyces aureofaciens which was bred by the graduated students in our laboratory, was optimized further in order to increase the yield of Streptomyces aureofaciens on the basis of present situation.Secondly, based on the study of mutation of Streptomyces aureofaciens by N⁺ implantation which was the contribution of the graduated students, we get high-yielding industrial strain L6-60^# from the industrial strain F₃^# mutated under the optimal implantation dose. The production of L6-60^# in shaking flask increases 12.2% than that of control, and both stability and productivity analyses showed the potential of L6-60^# for pilot-plant-scale test in the fermentation tank.Subsequently, mutant strain L6-60^# was used for production trial in 38 ton fermentor in No.101 workshop of Inner Mongolia JinHe Group. The results showed that the production, weight and net value of mutant strain increased 697U/mL, 0.83 ton and 39.88 billion/kg, respectively. Product analysis with High performance Liquid Chromatography indicated that the mutant strain could be used for industrial strain as both 4ECTC and TC were in the allowable range. Tracking measurements and System analyses of both mutant strain L6-60^# and control strain F₃^# were also carried out.And finally, bionitrogen as the most advanced nitrogen source, which could change the present situations of CTC fermentation instability, low fermentation level and high material price, was utilized instead of the peptone in CTC fermentation process.