Method for improving yield of glucosamine hydrochloride

Abstract

The invention discloses a method for improving the yield of glucosamine hydrochloride. The preparation method of the glucosamine hydrochloride comprises the following steps: filtering fermentation liquor prepared by a microbial fermentation method, adding a hydrogen chloride ethanol solution into the obtained filtrate to carry out acidolysis, adding a decolorizing agent into the obtained acidolysis solution after the reaction is finished, stirring and decolorizing, and filtering to obtain the glucosamine hydrochloride. And filtering, concentrating the obtained decolored solution under reduced pressure to a certain volume, cooling, crystallizing, washing, centrifuging and drying to obtain a glucosamine hydrochloride product. The yield of the prepared glucosamine hydrochloride is high, the purity of the obtained glucosamine hydrochloride can reach 99.9% or above, the yield can reach 80%-90%, and the preparation method is simple in process, environmentally friendly, economical and suitable for large-scale application and popularization.

Description

Technical Field

[0001] The present invention relates to the field of pharmaceutical chemistry, and particularly relates to a method for improving the yield of glucosamine hydrochloride. Background Art

[0002] Glucosamine hydrochloride is a derivative of glucose and is the basic building block of many important polysaccharides in organisms. Research shows that glucosamine hydrochloride has anti-inflammatory, anti-tumor, and antioxidant effects; it can be used clinically as a therapeutic drug for rheumatoid and rheumatic arthritis, and can also be used as an additive in infant foods, an antioxidant, and a sweetener for diabetic patients. It has a wide range of applications in the fields of nutritional health products, pharmaceuticals, cosmetics, and foods.

[0003] There are two traditional methods for preparing glucosamine hydrochloride. One is to prepare it by hydrolyzing chitin, but this process is restricted by factors such as the seasonal influence of raw materials, complex hydrolysis process, large consumption of acids and alkalis, and environmental pollution. The other is to produce N-acetylglucosamine through microbial fermentation and then prepare glucosamine hydrochloride by hydrolysis. The process of microbial fermentation has been widely applied and is accepted worldwide. However, in the process of preparing glucosamine by microbial fermentation, there is a problem of low efficiency in extracting glucosamine hydrochloride from the concentrated solution, resulting in waste of the target product as part of the glucosamine remains in the concentrated solution. Summary of the Invention

[0004] In view of the above problems, the present invention provides a method for improving the yield of glucosamine hydrochloride. The method of the present invention can not only promote the hydrolysis reaction efficiency, improve the product yield, but also reduce the use of solvents and simplify the process operation.

[0005] The present invention is achieved through the following technical solutions: (1) Filter the fermentation broth prepared by the microbial fermentation method and concentrate it under reduced pressure to obtain a concentrated solution; (2) Add a hydrogen chloride ethanol solution to the concentrated solution for acidolysis to obtain an acidolysis solution; (3) Add a decolorizing agent to the acidolysis solution, heat and stir, and filter to obtain a clear and transparent decolorized solution; (4) Cool the decolorized solution to crystallize, filter and wash, and dry to obtain the glucosamine hydrochloride product.

[0006] In the above method for improving the yield of glucosamine hydrochloride, in step (1), the fermentation filtrate is concentrated under reduced pressure to 25 - 50% of the initial volume, preferably 30%.

[0007] In the above method for improving the yield of glucosamine hydrochloride, in step (2), the volume ratio of the hydrogen chloride ethanol solution to the volume of the concentrated solution is 0.1 - 1.0:1, preferably 0.8.

[0008] In the above method for improving the yield of glucosamine hydrochloride, in step (2), the temperature of acidolysis is 75 - 80 °C, the time is 1 - 5 hours, and the preferred reaction time is 2 h.

[0009] In the above method for improving the yield of glucosamine hydrochloride, in step (3), the decolorizing agent includes any one of activated carbon, diatomite, and perlite, and activated carbon is preferred.

[0010] In the above method for improving the yield of glucosamine hydrochloride, in step (3), the added mass of the decolorizing agent is 0.1 - 0.5% of the solution mass, and 0.2% is preferred.

[0011] Preferably, in step (3), the decolorization process is: keep warm at 40 - 50 °C for 20 - 30 min.

[0012] In the above method for improving the yield of glucosamine hydrochloride, in step (4), the crystallization temperature is 0 - 30 °C, and 10 °C is preferred.

[0013] In the above method for improving the yield of glucosamine hydrochloride, in step (4), the crystallization time is 2 - 10 h, and 4 h is preferred.

[0014] The positive and progressive effects of the present invention are as follows: The method of the present invention uses hydrogen chloride ethanol for hydrolysis reaction, which not only promotes the reaction efficiency of hydrolysis, improves the product yield, but also reduces the use of organic solvents, simplifies the process operation, and is suitable for industrial production. Detailed Embodiments

[0015] The following further illustrates the present invention through examples, but does not limit the present invention.

[0016] Example 1

[0017] The fermentation filtrate was concentrated under reduced pressure at 60 °C to 30% of the initial volume. Hydrochloric acid ethanol was added to the obtained concentrated solution and hydrolyzed at 80 °C for 2 h. The volume ratio of the added hydrochloric acid ethanol to the volume of the concentrated solution was 0.2. After the hydrolysis was completed, 0.2% activated carbon was added to the acidolysis solution, heated to 50 °C, kept warm and stirred for 30 min, filtered through pressure filtration into the crystallization kettle, cooled to 10 °C for crystallization for 4 h, filtered and washed, and dried to obtain the glucosamine hydrochloride product. The content was 100.4%, and the yield was 89.4%.

[0018] Example 2

[0019] The fermentation filtrate was concentrated under reduced pressure at 60 °C to 30% of the initial volume. Hydrochloric acid ethanol was added to the obtained concentrated solution and hydrolysis was carried out at 80 °C for 2 h. The volume ratio of the added hydrochloric acid ethanol to the volume of the concentrated solution was 0.2. After the hydrolysis was completed, 0.2% activated carbon was added to the acidolysis solution, heated to 50 °C, kept warm and stirred for 30 min, filtered through pressure filtration into a crystallization kettle, cooled to 30 °C for crystallization for 4 h, filtered and washed, and dried to obtain the glucosamine hydrochloride product. The content was 100.2% and the yield was 82.4%.

[0020] Example 3

[0021] The fermentation filtrate was concentrated under reduced pressure at 60 °C to 50% of the initial volume. Hydrochloric acid ethanol was added to the obtained concentrated solution and hydrolysis was carried out at 80 °C for 5 h. The volume ratio of the added hydrochloric acid ethanol to the volume of the concentrated solution was 0.2. After the hydrolysis was completed, 0.2% activated carbon was added to the acidolysis solution, heated to 50 °C, kept warm and stirred for 30 min, filtered through pressure filtration into a crystallization kettle, cooled to 20 °C for crystallization for 4 h, filtered and washed, and dried to obtain the glucosamine hydrochloride product. The content was 99.8% and the yield was 81.2%.

[0022] Example 4

[0023] The fermentation filtrate was concentrated under reduced pressure at 60 °C to 25% of the initial volume. Hydrochloric acid ethanol was added to the obtained concentrated solution and hydrolysis was carried out at 80 °C for 2 h. The volume ratio of the added hydrochloric acid ethanol to the volume of the concentrated solution was 0.2. After the hydrolysis was completed, 0.2% activated carbon was added to the acidolysis solution, heated to 50 °C, kept warm and stirred for 30 min, filtered through pressure filtration into a crystallization kettle, cooled to 10 °C for crystallization for 4 h, filtered and washed, and dried to obtain the glucosamine hydrochloride product. The content was 99.9% and the yield was 85.1%.

[0024] The above details a method for improving the yield of glucosamine hydrochloride provided by the present invention. Specific examples are used herein to elaborate in detail on the implementation manners of the invention. The description of the above examples is to help understand the method and core idea of the present invention.

Claims

1. A method for improving the yield of glucosamine hydrochloride, characterized in that, the specific operation steps are as follows: (1) Filter the fermentation broth prepared by the microbial fermentation method, and concentrate it under reduced pressure to obtain a concentrated solution; (2) Add a hydrogen chloride ethanol solution to the concentrated solution for acid hydrolysis to obtain an acid hydrolysis solution; (3) Add a decolorizing agent to the acid hydrolysis solution, heat and stir, and filter to obtain a clear and transparent decolorized solution; (4) Cool the decolorized solution to crystallize, filter and wash, and dry to obtain the glucosamine hydrochloride product.

2. The method for improving the yield of glucosamine hydrochloride according to claim 1, characterized in that, in step (1), the fermentation filtrate is concentrated under reduced pressure to 25-50% of the initial volume to obtain a concentrated solution.

3. The method for improving the yield of glucosamine hydrochloride according to claim 1, characterized in that, in step (2), the volume ratio of the hydrogen chloride ethanol solution to the concentrated solution is 0.1-1.0:

1.

4. The method for improving the yield of glucosamine hydrochloride according to claim 1, characterized in that, in step (2), the temperature of the acid hydrolysis is 75-80 °C and the time is 1-5 hours.

5. The method for improving the yield of glucosamine hydrochloride according to claim 1, characterized in that, in step (3), the decolorizing agent includes any one of activated carbon, diatomaceous earth and perlite. Preferably, the added mass of the activated carbon, diatomaceous earth and perlite is 0.1-0.5% of the solution mass; preferably, in step (2), the decolorization process is: keep warm at 40-50 °C for 20-30 min.

6. The method for improving the yield of glucosamine hydrochloride according to claim 1, characterized in that, in step (4), the crystallization temperature is 0-30 °C.

7. The method for improving the yield of glucosamine hydrochloride according to claim 1, characterized in that, in step (4), the crystallization time is 2-10 h.