Method for producing L-aspartic acid converted from fumaric acid through Escherichia coli undergoing fermentation culture in large pot with volume of 20m<3>

Abstract

The invention relates to a method for producing L-aspartic acid converted from fumaric acid through Escherichia coli undergoing fermentation culture in a large pot with a volume of 20m<3>. A fluid medium 90% (v / v) is added in a large-scale fermentation pot, the diameter D of the pot body is 2200mm, and the height H0 of the pot barrel part is 5280mm. An Escherichia coli seed solution is inoculated, and the inoculation amount is 0.012% (v / v). The above mixture is cultured for 13h at a ventilation quantity of 280m<3> / h, at a rotating speed of 100rpm and at a pot pressure of 0.05MPa. A fermentation solution with a viable organism quantity of 1.89*108cfu / ml and an L-aspartic acid enzyme activity of 4725U / ml is prepared. Fumaric acid is converted through the fermentation solution and L-aspartic acid is obtained. The key of the method is that in the 20m<3> large pot fermentation of Escherichia coli HY-05C, the inoculation amount is low, only 2.1L of the shake flask seed solution is inoculated directly, the fermentation culture time is 13h, and a fermentation solution with high L-aspartic acid enzyme activity is obtained. Step by step amplification culture of seed pots is saved, and risks of bacterial infection during the seed amplification culture process are avoided. The production cycle is shortened and the production efficiency is raised.

Description

technical field [0001] The invention relates to the technical field of microbial fermentation, in particular to a method for industrially applying large-tank fermentation to produce L-aspartic acid. Background technique [0002] L-aspartic acid is an important amino acid, and it is the main raw material for the production of aspartame, polyaspartic acid and L-alanine. The market demand for these products is also increasing year by year. [0003] Aspartame is a new type of sweetener with a sweetness about 200 times that of sucrose, suitable for consumption by people with cardiovascular disease and obesity. The world needs about 60,000 tons of aspartame every year, and the demand is huge, which provides a huge market space for L-aspartic acid. Polyaspartic acid is a green and environmentally friendly polymer material. It is non-toxic, easy to biodegrade, and has good hydrophilicity and water solubility. As a high-quality corrosion inhibitor, chelating agent and dispersant, i...

AI Technical Summary

Problems solved by technology

However, due to the large investment in the immobilized cell method process equipment and high technical requirements, the production cost of the product is relatively high

Images