A kind of one pot method prepares the method for γ-glutamine compounds

Abstract

The invention discloses a one-pot method for preparing gamma-glutamine compounds. The method comprises the following steps of carrying out water phase amidation on 5-carboxyl ethyl hydantoin and amine compounds so as to form 5-carboxyl ethyl hydantoin amide compounds; after reaction, directly adding thallus containing both hydantoinase and carbamoyl enzyme without extraction and separation, and carrying out enzymatic hydrolysis ring opening reaction by taking the thallus as a catalyst so as to obtain the gamma-glutamine compounds. According to the method, a hydantoin ring is adopted for protecting both the alpha-amino and the alpha-carboxyl of glutamic acid, only the gamma-carboxyl is exposed, so that the position specificity of amidation is guaranteed; by adopting water phase amidation, the medium product does not need to be extracted and separated and can be directly used for enzyme reaction of the next step, in the 'one-pot method' reaction process, the reaction total recovery can be effectively improved, and the water phase reaction also avoids environment contamination caused by an organic solvent; and the enzymatic hydrolysis ring opening reaction avoids repeated protection and deprotection steps in most of the chemical synthesis reactions and reduces side reactions.

Description

technical field [0001] The invention relates to a method for preparing gamma-glutamine compounds by adopting a one-pot method. Background technique [0002] [0003] The γ-glutamine compound (1) is an amide compound formed by linking the γ-carboxyl group of glutamic acid and the amino group of the amine compound through a γ-amide bond. γ-glutamine compounds are not uncommon in nature, for example: glutamine is the most abundant free amino acid in biological organisms; theanine (γ-glutamylethylamine) is a unique amino acid in tea, accounting for More than 50% of the total amount of free amino acids in tea leaves is about 1% to 2% in dry tea leaves. It has important physiological and pharmacological effects, including relaxation, lowering blood pressure, anti-tumor, improving learning ability, neuroprotection, and anti-fatigue and immune effects, etc. (Shuai Yuying, Zhang Tao, Jiang Bo, etc. Research progress of theanine. Food and Fermentation Industry, 2008, 34(11): 117~1...

AI Technical Summary

Problems solved by technology

The extraction method is a classic production method, which mainly uses animal and plant tissues and yeasts containing γ-glutamine compounds as raw materials, and then separates and refines them by adding appropriate solvents or combining amylase and protease treatment, but due to the raw materials The content of γ-glutamine compounds in the medium is very low, and it needs to consume a lot of raw materials and solvents, so it is rarely used

Fermentation production is to select (construct) microorganisms with strong synthesis ability of γ-glutamine compounds and high content of intracellular products, screen and optimize culture formula, establish and optimize fermentation control strategy, improve and enhance downstream process technology, etc. Finally, the yield and quality of the product are improved. The main problems of the fermentation method are low conversion efficiency, long fermentation cycle, too low product content requires a complicated separation process, large equipment investment, high production cost, and relatively high product purity and yield. low, thus limiting the further promotion of the law

The chemical synthesis method usually needs to protect the α-amino group and α-carboxyl group of glutamic acid step by step, and only release the γ-carboxyl group for amidation reaction. -The protective group of the carboxyl group is removed, so that in the process of repeated protection and deprotection, it is easy to cause amide bond breakage, racemization, etc., thereby reducing the yield and optical purity

Suzuki et al. used γ-glutamyl transpeptidase to conduct a more detailed study on the enzymatic synthesis of γ-glutamyl compounds, and prepared γ-glutamines such as L-theanine and D-theanine. Compounds (Suzuki H, Yamada C, Kato K. γ-Glutamyl Compounds and Their Enzymatic Production Using Bacterial γ-Glutamyltranspeptidase. Amino Acids, 2007, 32: 333~340.), but because γ-glutamyl transpeptidase has both transpeptidase Peptide and hydrolysis activity are often accompanied by side reactions such as autorotation peptide and product hydrolysis during the reaction process, which makes the reaction process difficult to control and seriously affects the reaction efficiency

In our previous research (Cao Fei, Wei Ping, Zhou Jiadong, Wang Yuexia, Wu Hongli, Huang Rongxing, Zhang Furong. A method for enzymatically preparing optically active theanine. CN: ZL200910183579.9, 2009-09-23.) , the hydantoin enzymatic method is applied to the synthesis of theanine, but there are also the following two problems: on the one hand, when carrying out the amidation reaction, the organic phase condensation reagent is used in an organic solvent, and the organic solvent is harmful to the environment. It is unfriendly and harmful to the human body. At the same time, organic solvents generally have a high boiling point and require a higher price for product separation; on the other hand, the product of amidation reaction needs to be separated and extracted from the organic solvent first, and then added to water Enzyme-catalyzed hydrolysis ring-opening reaction in the phase, the extraction process will cause some product loss, resulting in a decrease in the overall yield

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