Method for producing L-hydroxyproline by microbial fermentation method

Abstract

The invention discloses a method for producing L-hydroxyproline by a microbial fermentation method. The method comprises the steps of inoculating fermentation culture mediums with escherichia coli, adding a carbon source and a nitrogen source to the fermentation culture mediums, in the presence of the carbon source, enabling the carbon source in aqueous mediums to be converted into L-hydroxyproline, and performing extraction on the aqueous medium so as to obtain the produced L-hydroxyproline; performing filtration on L-hydroxyproline fermentation liquid through a ceramic membrane to obtain trapped substances and a filtered clear solution, conveying the filtered clear solution into a nanofiltration membrane, performing impurity removal clarification to obtain a nano filtered clear solutionand a nano filtered trapped solution, and performing filtration and concentration on the nano filtered clear solution through a reverse osmosis membrane so as to obtain a concentrated solution; and decoloring the concentrated solution through activated carbon so as to obtain a L-hydroxyproline solution, conveying the L-hydroxyproline solution into an evaporator, and performing evaporation and crystallization so as to obtain white L-hydroxyproline crystals. Multi-stage membranes are combined with filtration and concentration, and the L-hydroxyproline is separated and extracted; on the base of guaranteeing the yield and the quality of L-proline by the technology, zero discharge of waste water is also realized; and in the fermentation culture mediums, sugar, glycol or organic acid is used asthe carbon source, and a large quantity of L-hydroxyproline is directly obtained.

Description

technical field [0001] The invention relates to a method for L-hydroxyproline, in particular to a method for producing L-hydroxyproline by microbial fermentation. Background technique [0002] L-Proline (L-Proline, C5H9NO2), also known as pyrrolidone carboxylic acid, is a cyclic neutral amino acid containing an imino group, one of the 20 basic amino acids that constitute proteins, and is a non-essential amino acid for the human body. As the main raw material of antiviral drug atazanavir, it has high application value. [0003] At present, the production methods of hydroxyproline reported at home and abroad mainly include proteolytic extraction method, chemical synthesis method, microbial fermentation method and enzymatic conversion method. Extracted from natural protein hydrolyzate, the raw materials used include gelatin, chicken feathers, fish skin or hair hydrolyzate, etc., but due to high production costs, it is not suitable for large-scale production in modern industrie...

AI Technical Summary

Problems solved by technology

Extracted from natural protein hydrolyzate, the raw materials used include gelatin, chicken feathers, fish skin or hair hydrolyzate, etc., but due to high production costs, it is not suitable for large-scale production in modern industries; direct fermentation method has low raw material cost and mild reaction conditions. Easy to mass produce

[0004] The known purification methods include ion exchange resin method and alumina chromatography. When separating L-proline by alumina chromatography column method, sometimes it is difficult to develop or elute with a solvent and the separation cannot be achieved. Therefore, the alumina chromatography column method has the disadvantages of time-consuming and difficult separation.

Using the ion exchange method, put the fermented broth from which the bacteria have been removed on the column at a specific pH condition, let the hydroxyproline be adsorbed on the ion exchange column, and then fully wash the ion exchange column with deionized water to remove impurities, and then use The eluent elutes hydroxyproline from the ion exchange column, but there are problems that hydroxyproline is easily oxidized and the yield is unstable