阅读说明：本技术 一种n-乙酰-d-氨基葡萄糖的生产方法 (Production method of N-acetyl-D-glucosamine ) 是由 卢健行 张建华 马善丽 卢建功 卢建智 姚珊珊 于 2019-11-22 设计创作，主要内容包括：本发明公开了一种N-乙酰-D-氨基葡萄糖的生产方法,以甲壳素为原料,在浓盐酸中水解制得氨基葡萄糖盐酸盐,通过乙酰化制得N-乙酰-D-氨基葡萄糖；本发明给出了最适合工业化的生产途径和反应条件,可实现高纯度N-乙酰-D-氨基葡萄糖的工业化生产。(The invention discloses a production method of N-acetyl-D-glucosamine, which takes chitin as a raw material, hydrolyzes the chitin in concentrated hydrochloric acid to prepare glucosamine hydrochloride, and prepares the N-acetyl-D-glucosamine by acetylation; the invention provides the most suitable industrialized production way and reaction conditions, and can realize the industrialized production of the high-purity N-acetyl-D-glucosamine.)

1. A production method of N-acetyl-D-glucosamine is characterized in that: the method comprises the following steps:

(1) taking chitin as a raw material, adding the chitin into concentrated hydrochloric acid in batches by adopting an interval feeding method under the stirring condition, slowly heating to 90-110 ℃ by adopting a gradient heating method, and reacting for 10-20min by maintaining the reaction temperature;

(2) decolorizing and recrystallizing the mixed solution obtained by the reaction to obtain glucosamine hydrochloride;

(3) dissolving the prepared glucosamine hydrochloride in pyridine, adding triethylamine, adding acetic anhydride under the stirring condition, and stirring for reaction for 1-3 h;

(4) and (4) carrying out suction filtration on the reaction product obtained in the step (3), washing with acetone, recrystallizing, and drying in vacuum to obtain the N-acetyl-D-glucosamine.

2. The process for producing N-acetyl-D-glucosamine according to claim 1, wherein: the temperature rising rate of the gradient temperature rising method in the step (1) is 10-15 ℃/h.

3. The process for producing N-acetyl-D-glucosamine according to claim 1 or 2, wherein: the concentrated hydrochloric acid in the step (1) is concentrated hydrochloric acid with the volume concentration of 30-40%.

4. The process according to claim 3, wherein the N-acetyl-D-glucosamine is produced by: in the step (1), the mass ratio of the chitin to the concentrated hydrochloric acid is 1 (5-8).

5. The process for producing N-acetyl-D-glucosamine according to claim 1, wherein: the decoloring process in the step (2) comprises the following steps: adding activated carbon into the reaction mixture for decolorization and adsorption, stirring at 40-50 ℃ for 2-4h, and filtering.

6. The process according to claim 5, wherein the N-acetyl-D-glucosamine is produced by: the mass fraction of the activated carbon in the mixed solution is 4-8%.

7. The process for producing N-acetyl-D-glucosamine according to claim 1, wherein: and (3) recrystallizing in the step (2) by using an 85-95% ethanol solution.

8. The process for producing N-acetyl-D-glucosamine according to claim 1, wherein: and (3) adjusting the pH value to 7-8 by using sodium methoxide in the reaction process.

9. The process according to claim 8, wherein the N-acetyl-D-glucosamine is produced by: the mol ratio of glucosamine hydrochloride to acetic anhydride in the step (3) is 1: (2-5).

10. The process for producing N-acetyl-D-glucosamine according to claim 1, wherein: and (4) recrystallizing with acetone.

Technical Field

The invention belongs to the technical field of biochemical synthesis, and particularly relates to a production method of N-acetyl-D-glucosamine.

Background

Glucosamine (GleN) is an important hexosamine formed by substituting one hydroxyl group of glucose with an amino group, and there are two main types of glucosamine on the market today, one is glucosamine hydrochloride and the other is glucosamine sulfate. D-Glucosamine Hydrochloride (D-Glucosamine Hydrochloride), molecular formula C₆H₁₃NO₅HCl, a white crystal, odorless, slightly sweet, readily soluble inWater, slightly soluble in methanol, insoluble in organic solvents such as ethanol and the like, has important physiological functions for human bodies, participates in liver and kidney detoxification, plays a role in resisting inflammation and protecting liver, has good curative effect on treating rheumatic arthritis and gastric ulcer, and is a main raw material for synthesizing antibiotics and anticancer drugs; can also be used in food, cosmetic and feed additive. Glucosamine hydrochloride is extracted from natural chitin, is a marine biological agent, and is the main component of chondroitin sulfate. It can promote the synthesis of mucopolysaccharide, raise the viscosity of joint synovial fluid, improve the metabolism of joint cartilage, promote the repair of joint cartilage and has obvious antiphlogistic and analgesic effects. It has the effect of promoting the injection efficiency of antibiotics, and can be used as nutritional supplement for diabetic patients.

N-acetyl D-glucosamine is white needle crystal, has no odor, is easily soluble in water, is an important glucosamine derivative, is a basic composition unit of a plurality of important polysaccharides in biological cells, is a special monosaccharide with higher sweetness, has reducibility, is an important precursor for synthesizing bifidus factors, has important physiological functions in organisms, is clinically a medicament for treating rheumatic and rheumatoid arthritis, is also used as a food antioxidant, an infant food additive and a sweetener for diabetics. The method is widely applied to the fields of food, medicine, chemical industry and the like, and has wide market prospect. The prior production method has complex process and low yield, so that the production cost is high, and the subsequent production and application are limited.

Disclosure of Invention

In order to make up the defects of the prior art, the invention provides an industrialized preparation method of N-acetyl-D-glucosamine, which has the advantages of high production efficiency, low cost and simple operation.

The invention is realized by the following technical scheme:

a production method of N-acetyl-D-glucosamine is characterized in that:

the method comprises the following steps:

(1) taking chitin as a raw material, adding the chitin into concentrated hydrochloric acid in batches by adopting an interval feeding method under the stirring condition, slowly heating to 90-110 ℃ by adopting a gradient heating method, and reacting for 10-20min by maintaining the reaction temperature;

(2) decolorizing and recrystallizing the mixed solution obtained by the reaction to obtain glucosamine hydrochloride;

(3) dissolving the prepared glucosamine hydrochloride in pyridine, adding triethylamine, adding acetic anhydride under the stirring condition, and stirring for reaction for 1-3 h;

(4) and (4) carrying out suction filtration on the reaction product obtained in the step (3), washing with acetone, recrystallizing, and drying in vacuum to obtain the N-acetyl-D-glucosamine.

Preferably, the temperature rising rate of the gradient temperature rising method in the step (1) is 10-15 ℃/h.

Further, the concentrated hydrochloric acid in the step (1) is concentrated hydrochloric acid with the volume concentration of 30-40%.

Further, the mass ratio of the chitin to the concentrated hydrochloric acid in the step (1) is 1 (5-8).

Preferably, the decoloring process in the step (2) is as follows: adding activated carbon into the reaction mixture for decolorization and adsorption, stirring at 40-50 ℃ for 2-4h, and filtering.

Furthermore, the mass fraction of the activated carbon in the mixed solution is 4-8%.

Further, the recrystallization in the step (2) is carried out by using an 85-95% ethanol solution.

Preferably, the reaction process in the step (3) is adjusted to pH 7-8 by sodium methoxide.

Further, in the step (3), the molar ratio of the glucosamine hydrochloride to the acetic anhydride is 1: (2-5).

Preferably, the step (4) is performed by recrystallization with acetone.

The invention has the beneficial effects that: the method takes chitin as a raw material, realizes the rapid preparation of the N-acetyl-D-glucosamine by controlling each reaction condition, obtains the high-purity reaction condition which is most suitable for industrialization by a large amount of groping, not only reduces the reaction cost, but also improves the purity of the N-acetyl-D-glucosamine, has easily controlled reaction process, and is beneficial to industrialized production.

Detailed Description

The present invention will be described in further detail with reference to specific embodiments thereof to assist those skilled in the art in providing a more complete, accurate and thorough understanding of the inventive concept and aspects thereof, and the scope of the present invention includes, but is not limited to, the following examples, and any modifications in the details and form of the technical aspects thereof that fall within the spirit and scope of the present application are intended to be included therein.