S-adenosyl-Lmethionine Breeding And High-Yield Strains Of The Fermentation Process Of Optimization

S-adenosyl-L-methionine(s-adenosyl-L-methionine,as SAM),is important in the middle of metabolic body,has to methyl,to sulfur,such as to aminopropyl, homocysteine is,Taurine,Gu Gan-peptide,coenzyme A,and other important precursor substances.To treat nervous disorders,depression,arthritis and other diseases,has a huge demand on the international market.SAM of this paper have carried out a fermentation process of breeding and research results are as follows:Through the production of S-adenosylmethionine strains of Saccharomyces cerevisiaeB9 to separate Rejuvenation,access to a relatively stable genetic strains of SAM-39^#(1.765g/L),SAM-39^# as the starting to strain mutation Breeding, finally starting strain than the SAM-39^# high yield 69.89 percent of the mutation of YZ-33,its SAM content 3.001g/L,and UV-induced,protoplast renewable breeding methods to raise production ineffective.By comparison found: ultraviolet-lithium chloride compound and protoplast UV-induced mutation of the SAM production of the mutagenic effects better.High-yield stability to the mutation of YZ-33 as the starting strain,through the determination of the growth curve,and explore a snail's pace of the enzyme concentration,time,temperature and other factors on the formation of protoplasts,identified protoplast of the best conditions are as follows:seeds of training 16 hours,0.1%β-mercaptoethanol pretreatment 10 min,enzyme concentration of 2.5 percent,hydrolysis time 150 min,with 0.5 mol/L sucrose as the infiltration of stability.YZ-33 against the strain does not change the original composition of the medium on the basis of its various components of a orthogonal experiment,to fred the best ratio.That the best medium for the formula:12 percent sugar,ammonium chloride 0.8%,0.8%yeast powder,magnesium sulfate 0.005%,L-methionine 1.2%,0.4%potassium dihydrogen phosphate,hydrogen phosphate 2 Potassium 0.2 percent.In addition,the YZ-33 on the fermentation process of pH,biomass,SAM content,sugar content,NH₄⁺,and other metabolic parameters were measured for the fermentation process of the establishment of SAM to provide a reference.Also,on the feeding process done a preliminary study to determine the feeding process and the most appropriate feeding methods.Initial feeding process is:L-Met-batch final concentration of 0.8 percent,the ted-start time 24h,the final concentration of sucrose feeding 10 percent,fed-time 48h;most appropriate way for the feeding:24h adding 0.6% L-met,3%sucrose,in 48h by 0.2 percent-plus L-Met,sucrose in 48h and 72h respectively by 2.5 percent recharge.In such conditions SAM-batch production totaled 4.041g/L.