Industrial Process Control Of Inosine And Studies On The Fermentation Conditions

According to the theory of metabolic control fermentation，the dissertation researches onthe industrial production in100m3fermenter of inosine fermentation for the first time. Basedon the large-scale production data, the metabolic flux and kinetics of batch fermentation ofinosine fermentation were studied. The fermentation conditions and control technology wereoptimized to provide theoretical guidance for large-scale production and improve the yield ofinosine.Using Bacillus subtilis of adenine-deficient as the production strain, the metabolicbehavior of inosine fermentation process was researched. The optimal culture conditions ofprimary and secondary seed were determined by the method of uniform design. Comparedwith the batch culture progress, the two programs of sugar-supplement craft in the late stageof fermentation were analyzed. The results showed that the production rate can be affected inthe process of sugar-supplement, but the final yield increased, so the sugar-supplement craftcontributed to lowering production costs. Theoretically, sugar supplement craft inpre-fermentation can increase production and shorten fermentation period, but we did not trythe method considering for pollution prevention. Effect of different nitrogen source on inosineproduction was studied: Compared with using yeast alone, the yield of inosine increased13.28%by using organic nitrogen source A, and the rate of oxygen consumption accelerated.Using organic nitrogen source B instead of50%of organic nitrogen source A by theproportion of1:2, the yield of inosine increased8.04%in addition, and the rate of sugarconsumption accelerated,what can shorten the fermentation period by4h. Using organicnitrogen source B was a significant progress in the nitrogen source selection. Theconcentration of inorganic salts such as potassium dihydrogen phosphate and ammoniumsulfate, also had an impact on the production of inosine. Dissolved oxygen can limit theproduct formation of inosine fermentation. It was conducive to the production of inosine bycontroling dissolved oxygen level of10%to30%in pre-fermentation. In addition, for theimportant work of pollution prevention in industrial fermentation, the medium composition,preparation of materials and sterilization were improved in this paper,what can help to reducethe contamination rate.