Studies On The Culture Process And Method Of Clostridum Butyricum

Clostridium butyricum is a probiotics present in the intestine of humans and livestock which can improve the balance of intestinal bacterial ecosystem of the host.Clostridium butyricum has a good effect on the treatment of various diseases due to intestinal diseases.Beside these,C.butyricum also could improve the ability of bodily growth of livestock.So,C.butyricum widely used in food and pharmaceutical industries.The related products of Clostridium butyricum were exist in form of live cells.Therefore,in this study,the main goal was to improve the biomass and spore yield of Clostridium butyricum,the traditional fermentation culture method and the mathematical analysis software were used to optimize fermentation process.Due to Clostridium butyricum belongs to strictly anaerobic bacteria,so we explored a Fe-C primary battery system to create a oxygen-free environment for culturing Clostridium butyricum.1.Mathematical analysis method was employed to optimize fermentation process for improving the biomass of Clostridium butyricumm.On the basis of single factor experiment,factors which influenced the biomass of Clostridium butyricumm significantly were screened by Plackett-Burman design.On this basis,the steepest ascent experiment was applied to find out the center point of central composite design.Finally,the maximum response value was identified by CCD.The results showed that: Yeast extract powder,FeSO₄ and K₂HPO₄ were the three factors influencing the biomass of C.Butyricumm significantly;soluble starch 2%,yeast extract powder 6%,FeSO₄ 1.74%,K₂HPO₄ 0.37%,NaCl 0.2% and MgSO₄ 0.024% were the best combination of medium component.The optimum culture conditions were: temperature37℃,pH7.0,inoculum volume 4%.The biomass of Clostridium butyricum reached1.01×109cells/mL which was 4.39 times higher than that of before optimization.2.In the process of improving the yield of spores,lactose was found to be the best carbon source for Clostridium butyricum,and the content of DPA in spores was used as the detection index to determine the number of spores.On the basis of above,factors of MgSO₄ and lactose which influenced the DPA concentration of Clostridium butyricumm significantly were screened by Plackett-Burman design.Then the steepest ascent experiment was applied to find out the center point of central composite design.Finally,the maximum response value was identified by CCD.The result showed that lactose0.3%,MgSO₄ 0.035%,yeast extract powder 1.0%,NaHCO₃ 0.2%,K₂HPO₄ 0.3%,KH₂PO₄ 0.3% were the best combination of medium component.The optimum culture conditions were: temperature 43℃,pH7.0,inoculum volume 2%.The DPA concentration of Clostridium butyricum reached 15.16 μM which was 7.5 times higher than that of before optimization.The final spore number was 6.31×107 个/mL,the spore conversion rate was 60%.3.Examination of the effect of Fe-C primary battery system on the fermentation performance of anaerobic bacteria C.butyricum was performed.The best composition of Fe-C primary battery system: Fe powder 0.5%,C powder 0.3%.The results showed that this system has a great promotion on the growth of C.butyricum.It can maintain alow redox potential in the culture media for better growth of C.butyricum.Compared with control（without Fe-C system）,its maximum specific growth rate increased form0.23h-1 to 0.43h-1,growth yield increased from 0.10 g cell/g glucose to 0.14 g cell/g glucose.The final biomass production increased from 0.71g/L to 1.31g/L.In addition,the Fe-C system could releasing acid inhibition along with the reduction of specific productivity of organic acids.The specific productivity of buytic acid was reduced from0.15 g /g glucose·h to 0.10 g /g glucose·h,the specific productivity of acetic acid was reduced from 0.28 g /g glucose·h to 0.18 g /g glucose·h.