Adjusting ph to improve the fermentation process of recombinant human collagen production level

Abstract

The invention discloses a fermentation process for regulating pH and improving a production level of recombinant human collagens. The process comprises the following steps: inoculating pichia pastorisculture liquid into a sterile fermentation medium, controlling the pH value to be 5.2-5.4 at the initial growth phase, fermenting and culturing for 14-18 hours, regulating the pH value to 4.8-5.0, and supplementing methanol to perform induced expression. According to the process disclosed by the invention, in the fermentation process, the pH value is reduced at the methanol induced expression stage, strain growth is controlled, the biosynthesis rate of the recombinant human collagens is improved, the biosynthesis rate of the recombinant human collagens can be further improved, and the fermentation time is shortened. Meanwhile, the expression quantity of the recombinant human collagens is increased, the fermentation level is improved by 20% or higher, the production cost is saved, and particularly the process is applicable to large-scale industrialized production of the recombinant human collagens and can bring huge actual application value for the industrialized production.

Description

technical field [0001] The invention belongs to the technical field of biological fermentation and relates to a fermentation process for adjusting pH to increase the production level of recombinant human collagen. Background technique [0002] Collagen is an important protein in animals. It is widely distributed in tissues such as skin, cartilage, and blood vessels. It participates in cell migration, differentiation, and reproduction, and plays an important role in maintaining the normal physiological functions of cells, tissues, and organs. It is used in food , Feed, beauty, cosmetics, medicine and other fields are widely used. At present, collagen raw materials are mainly obtained by separation and purification after treating animal skin, bone and other tissues such as pigs and cattle with physical and chemical methods such as acid, alkali and heating. However, the collagen obtained by the above method has complex components and poor water solubility, and because it comes...

AI Technical Summary

Problems solved by technology

Compared with the traditional process, the fermentation process of genetically engineered bacteria of collagen has the advantages of easy availability of raw materials, environmental protection, and stable product quality, but there are also problems such as longer fermentation cycle and lower production efficiency.

Chinese patent 201010602214.8 discloses a production method for expressing recombinant human-like collagen in Pichia pastoris. Pichia pastoris C13 is used as the strain, the expression level of recombinant collagen is 5g / L, the fermentation period is 99 hours, and the fermentation level 0.051g / L·h, although the fermentation cycle is short, the protein expression and fermentation level are too low

Chinese patent 201110327865.5 constructed a Pichia pastoris genetically engineered strain of recombinant human collagen. The genetically engineered strain was fermented to obtain recombinant human collagen. The fermentation period was 136 hours, and the protein expression was 16g / L. The level is 0.118g / L·h, although the protein expression has increased, but the fermentation period is too long and the fermentation level is low