Study On The Preparation Of4’-epi-Daunorubicin Produced By Gene Engineering Strain

4’-epi-daunorubicin is the first line anti-tumor chemotherapeutic agent and alsoan important precursor of semi-synthetic epirubicin. Thus, gene engineering strainproduct4’-epi-daunorubicin has the advantages in eliminating several synthetic steps,cost reduction and more environment-friendly in epirubicin production. This paperwas about4’-epi-daunorubicin of which fermentation and separation and purificationprocess was systematically explored.The original strain SIPI-A0707producing4’-epi-daunorubicin was separated anda high-yielding stable strain N25was obtained. Firstly, UV mutagenesis has been usedand optimum dose of UV mutagens was investigated. Two consecutive UVmutagenesises were conducted at the optimum dose and each of the high-yield strainswas studied for stability. A stable strain UV21was obtained, the production of whichwas21%higher than original strain. Then，product tolerance screening have beenused to UV21and optimum dose of product(Daunorubicin) was investigated. At theoptimum dose, each of the high-yield strains was studied for stability. Finally，a stablestrain SIPI-A0708was obtained, the production of which was44%higher thanSIPI-A0707.An optimum composition of medium was obtained by studying the influences ofdifferent carbon sources, nitrogen sources, concentrations of phosphate on thefermentation of SIPI-A0708. Meanwhile, the fermentation conditions were alsooptimized by studying the influences of some parameters on fermentation. Theproduction of4’-epi-daunorubicin was increased by96%under the optimizedconditions of fermentation. Fermentation was scaled up to15L, the production of4’-epi-daunorubicin was increased by129%.The program of separation and purification of4’-epi-daunorubicin was optimized.Firstly,4’-epi-daunorubicin was extracted from fermentation broth. Secondly suitablemacroporous weak acid cation exchange resin was selected through studying theparameters of adsorption and elution, purpose of which enriched the4’-epi-daunorubicin and removed some impurities. Thirdly the suitable macroporousresin was selected through studying the parameters of adsorption and elution. Finallyproduct was obtained by freeze-dried. The HPLC purity of the product is98.1%, andtotal yield was over40%.