Method for producing malic acid by fermentation of citric acid mother liquor

Abstract

The invention relates to a method for producing malic acid by fermentation of citric acid mother liquor. In the method, with the citric acid mother liquor as a carbon source, a strain capable of producing fumarase by fermentation produces fumarase, and fermentation liquor is used as a raw material to convert sodium fumarate. After 20 to 25 hours of conversion, the content of L-malic acid reaches about 1.1 mol / L, and the conversion rate is about 94 percent. In the invention, performed separately, the fumarase production and conversion both can be performed under more proper conditions; the process is simple; energy consumption is small; the raw material is cheap; and the substrate conversion rate is high.

Description

technical field

[0001] The invention relates to a method for producing malic acid, in particular to a method for fermenting and producing malic acid by using citric acid mother liquor as a raw material. Background technique

[0002] There are two types of malic acid, L-malic acid and DL-malic acid, and L-malic acid is widely found in plants or their fruits. Its molecular formula is C 4 h 6 o 5 , relative molecular weight 134, white crystal or crystalline powder. At present, the production methods of L-malic acid include direct fermentation method, two-step fermentation method and immobilized cell continuous enzymatic production process.

[0003] L-malic acid is in a pivotal position in the process of glucose metabolism in organisms, and is an intermediate product of the tricarboxylic acid cycle and the glyoxylate cycle. The physiological effects of L-malic acid are mainly manifested in: (1) Anti-fatigue effect. Malic acid can be directly absorbed by the human body, and...