High-density culture method for slow-growing rhizobium japonicum

Abstract

The invention discloses a high-density culture method for slow-growing rhizobium japonicum, and belongs to the technical field of heterotrophic culture fermentation processes. The method solves the problems that the carbon nitrogen ratio in the logarithmic phase is unbalanced, the growth of thalli is poor due to the increase of metabolites, and the high-density culture of the slow-growing rhizobium japonicum cannot be realized in the conventional method for culturing the rhizobium japonicum in a fermentation tank. According to the method, a constant-speed fed-batch feeding mode is adopted, the ratio and concentration of carbon and nitrogen in fermentation liquor are effectively maintained, the viable count of the slow-growing rhizobium japonicum in the logarithmic phase is effectively increased, the final effective viable count of fermentation is stabilized at 6.8 * 10 < 9 > cfu/mL, and high-density culture of the rhizobium japonicum is achieved. In addition, the adopted constant-speed fed-batch feeding mode is easy to operate, amplification culture is easier, and the method is more suitable for large-scale production.

Description

technical field [0001] The invention relates to a high-density culture method for brady-growing soybean rhizobia, belonging to the technical field of heterotrophic culture and fermentation technology. Background technique [0002] The nitrogen nutrition required for soybean growth is basically provided by rhizobia. If there is no rhizobia, more than 100 kilograms of urea per mu can be applied to meet the nitrogen fertilizer demand of 180 kilograms of soybeans per mu. Therefore, the nitrogen fertilizer of soybeans is basically Contributed by rhizobia. [0003] At present, in the prior art, fermenter culture is usually used to increase the stirring speed and ventilation volume to increase the effective number of viable bacteria of the brady-growing soybean rhizobia, but the final effective number of viable bacteria in the existing conventional fermentation culture is about 1.9×10 8 cfu / mL, the high-density culture of brady-growing soybean rhizobia has not yet been achieved. ...

AI Technical Summary

Problems solved by technology

[0003] At present, in the prior art, fermenter culture is usually used to increase the stirring speed and ventilation volume to increase the effective number of viable bacteria of the brady-growing soybean rhizobia, but the final effective number of viable bacteria in the existing conventional fermentation culture is about 1.9×10 8 cfu / mL, high-density cultivation of brady-growing soybean rhizobia has not yet been achieved

Therefore, it is very necessary to provide a method that can effectively solve the imbalance of the carbon-nitrogen ratio in the logarithmic phase, and the increase of metabolites is not good for the growth of the bacteria, so as to realize the high-density cultivation of the slow-growing soybean rhizobia

Images