利用Clostridium acetobutylicum 發酵生產丁醇之培養策略探討

A study of Butanol Production on Clostridium acetobutylicum by Varies of Fermentation Strategy

施舒容(Shu-Rong Shih)

指導教授 ： 魏毓宏

元智大學/工程學院/生物科技與工程研究所/碩士(2012年)

摘要

本研究首先針對碳源(葡萄糖, glucose)的濃度(10-50 g/L)進行探討。研究結果指出，以50 g/L為碳源發酵時，可以得到0.43 g/L丁醇。
之後便並進一步探討不同碳源—甘油(glycerol)對於丁醇生產的效果，結果發現確實有提升丁醇產量之功用。
本研究進一步探討氮源(yeast extract, tryptone, peptone)對生產丁醇的影響，研究結果發現，培養基同時以添加三種氮源做為微生物培養基，其丁醇的產量較個別單一氮源的產量最高可達到1.5倍，顯示此三種氮源的添加有其必要性，對菌體的生長尤其重要。
除碳氮、源外，本研究同時針對trace elements(Fe、Mg)進行探討。研究結果發現，不同FeSO4．7(H2O)的濃度對微生物的生長並無影響，但很明顯的0.0025 g/L FeSO4．7(H2O)可產生0.7 g/L的丁醇；另外，發現不同濃度的MgSO4．7(H2O)對菌體是有影響的，從實驗結果來看，會發現菌體生長隨著MgSO4．7(H2O)濃度越高，在同個時間內菌體值越高，此外，亦發現丁醇濃度在0.05 g/L MgSO4．7(H2O)下可達到0.8 g/L，其餘丁醇濃度皆在0.4 g/L，由此實驗可知MgSO4．7(H2O)對丁醇產量有幫助，但是濃度不能過高(0.2 g/L)，也不能過低(0.0192 g/L)，否則會影響丁醇生產。

關鍵字

丁醇 ； 微生物發酵

並列摘要

In these studies, we investigated the effect of carbon source (glucose) with different concentrations (10-50 g/L) associated with Clostridium acetobutylicum ATCC 824 growth and butanol production. These results suggest that it produced 0.43 g/L butanol in 60 h with 50 g/L glucose as carbon source. Using medium containing glycerol, instead of glucose as a carbohydrate source, we measured characteristics of the fermentation
including solvent production. With glycerol/glucose as substrate, the culture produced 1.6 g /L butanol.
When yeast extract, tryptone and peptone were introduced into the fermentation medium, growth and ABE production by C.acetobutylicum ATCC 824 increased significantly. Besides that, medium supplemented with cysteine-HCl promote bacterial growth, but it doesn't affect the butanol production and by adding glutathione to the growth medium bio-butanol production can be increased from 0.2 g/L to 0.4 g/L. Finally, the addition of 0.025 g/L traces elements (FeSO4．7(H2O)) can also improve the yield of bio-butanol to 0.7 g/L.

並列關鍵字

Butanol ； Clostridium acetobutylicum

參考文獻

Ezeji, 2012. Energy requirements during butanol production and in situ recovery by cyclic vacuum. Renewable Energy 47, 183–187.

of acetone and butanol by Clostridium acetobutylicum in a two-stage

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15(4): 201-205.

Biebl, H., 2001. Fermentation of glycerol by Clostridium pasteurianum — batch and continuous culture studies. Journal of Industrial Microbiology & Biotechnology 27, 18 – 26