Method for improving quality and yield of 3,4-dihydroxyphenyl-L-ananine products

Abstract

The invention relates to a method for improving quality and yield of 3,4-dihydroxyphenyl-L-ananine products. The method comprises the following steps of (1) performing fermentation to obtain tyrosinephenol lyase; (2) preparing a substrate solution; (3) preparing material complementing liquid: after running water is boiled over, introducing nitrogen, lowering the temperature to be 10-25 DEG C, firstly, adding an antioxidant, adding 2-5g / L of sodium sulfite and 0.5-2g / L of ascorbic acid, then adding 100-160g / L of sodium pyruvate, 100-160g / L of catechol, 10-20g / L of ammonium acetate and 1-3g / L of EDTA, and regulating the pH to be 7.5-8.5; and (4) continuously introducing nitrogen for the substrate solution, adding the substrate solution to enzymes, sealing a reaction container for oxygen separation, introducing small amount of nitrogen for maintaining positive pressure, performing uniform stirring, performing sealing at 16-25 DEG C, performing vibration for a reaction, adding the material complementing liquid (sealing a material complementing container in a flowing manner, and continuously introducing small amount of nitrogen for maintaining positive pressure ), and when the flowingaddition of the material complementing liquid is finished and the concentration of catechol is lower than 0.05g / L, stopping the reaction. The product quality is improved, the conversion rate of the catechol is increased, and the product yield is increased. The method has high application value during industrialized production.

Description

technical field [0001] The invention relates to a method and application for improving product quality and yield in the process of producing levodopa by enzymatic catalysis, and belongs to the field of enzymatic catalysis technology. Background technique [0002] The chemical name of levodopa (3,4-dihydroxyphenyl-L-ananine, referred to as L-DOPA) is 3,4-dihydroxyphenylalanine, and its structural formula is: [0003] [0004] As an important biologically active substance, L-DOPA is an important intermediate product in the biochemical metabolic pathway from L-tyrosine to catechol or melanin. [0005] In the 1960s, many foreign scholars began to devote themselves to the research of microbial enzymatic synthesis of L-DOPA. In order to increase the yield of L-DOPA and the conversion rate of the substrate, researchers have conducted a lot of research on the process of microbial enzymatic synthesis of L-DOPA. [0006] Tyrosine phenol lyase (Tyrosine phenol lyase, TPL, E.C.4.1....

AI Technical Summary

Problems solved by technology

Since the substrate catechol and the product levodopa are easily oxidized in solution, black oxides are generated, which seriously affects the product quality and reduces the yield of L-DOPA

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