Vitamin B_<12> production from a high effective methane fermentation system by CO_2 using acclimated-methogens

使用驯化方法通过 CO_2 高效甲烷发酵系统生产维生素 B_<12>

• 批准号: 11660320
• 负责人: ZHENYA Zhang
• 金额: $ 2.18万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11660320/
• 关键词: H_2 using methangens; CO_2 fixation and reuse; New method of vitamin B12 production; Reuse of resources; separation and refinement; CO_2利用-固定; 新規ビタミンB_<12>生産法; 水素資化性メタン菌; 高密度メタン菌培養; ビタミンB_<12>分離・精製

In this study, vitamin B_<12> was isolated and quantified from the culture broth of acclimated-methanogens. The methanogens were cultivated in the stopped tubes in the batch feed substrate gas (H_2/CO_2, 80 : 20v/v) at pH7 and 37℃. A novel isolation method for vitamin B_<12> was attempted using a centrifuge tube filled with Amberlite XDA-2. Using this method, the separation of vitamin B_<12> can be done quickly compared to previous techniques. A high concentration above 110mg/L of vitamin B_<12> in the culture broth was detected. For vitamin B12 production, the optimum Fe/Co ratio was investigated, we found that with the Fe/Co of 0.2-0.6, the maximum vitamin B12 was obtained. In the case of using methanogens fixed rector with the sponge gourd as carrier at HRT 6 days, we obtained the vitamin B12 concentration in culture broth as 37.5 mg/L (Fig.6), the productivity is 110-150 times higher than conventional production method. This investigation indicates that acclimated-methanogens using CO_2/H_2 excretes corrinoids into the extracellular culture broth during growth, and suggests that the continuous production of extracellular corrinoids using the methanogens cultivation system is possible.

本研究从驯化产甲烷菌的培养液中分离并定量了维生素B_<12>。在pH7、37℃条件下，间歇式进料底物气体（H_2/CO_2, 80: 20v/v）中，停管培养产甲烷菌。用Amberlite XDA-2填充离心管分离维生素B_<12>。与现有技术相比，该方法可快速分离维生素B_<12>。在培养液中检测到维生素B_<12> > 110mg/L的高浓度。对于维生素B12的生产，研究了最佳Fe/Co比，发现Fe/Co为0.2 ~ 0.6时，维生素B12产量最高。以海绵葫芦为载体，采用产甲烷菌固定载体，在HRT 6 d时，培养液中维生素B12浓度为37.5 mg/L（图6），产量比常规生产方法提高110-150倍。本研究表明，采用CO_2/H_2的驯化产甲烷菌在生长过程中会向胞外培养液中排放角蛋白，表明利用该体系连续生产胞外角蛋白是可能的。