Disclosure of Invention
In view of the above problems, the main object of the present invention is to provide a method for preparing glucosamine hydrochloride by using a glucosamine fermentation broth, which can effectively overcome some problems caused by the prior fermentation method for preparing glucosamine hydrochloride. In order to realize the purpose, the invention discloses the following technical scheme:
a method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2Mixing and stirring, stopping stirring when floc is generated, standing, and filtering after the floc is not generated any more to obtain filtrate for later use.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with a nano aperture, then adding active carbon into the obtained filtrate again, and filtering to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution obtained in the step (2) and NH4And placing the mixed solution of the Cl solution and the volatile organic alcohol in a closed reaction container, heating the reaction container, and carrying out solid-liquid separation after the reaction is finished to obtain hydrolysate.
(4) And (4) adding excessive NaOH into the hydrolysate obtained in the step (3), then reacting under a heating condition, and adjusting the pH of the reaction solution by using hydrochloric acid after the reaction is finished to obtain a glucosamine hydrochloride solution.
(5) And (4) drying the glucosamine hydrochloride solution obtained in the step (4).
Preferably, in step (1), 2Na is contained in the fermentation liquid2CO3·3H2O2The concentration of (A) is 6.5-9 mg/L. 2Na2CO3·3H2O2After being mixed with fermentation liquor, the mixture reacts with water to generate hydroxyl ions, and the hydroxyl ions are further converted into active oxygen, so that the sedimentation of thalli can be effectively promoted.
Preferably, in the step (3), the volatile organic alcohol includes at least one of methanol, ethanol, propanol, and the like. In the invention, the added volatile organic alcohol is heated to be in a gaseous state, so that the reaction environment is kept at a high pressure continuously, the hydrolysis of the acetylglucosamine is accelerated, the volatile organic alcohol can be removed conveniently after the reaction is finished, and no additional impurity ions are introduced into the hydrolysate.
Preferably, in the step (3), the volume ratio of the volatile organic alcohol to the ammonium salt solution is 0.28-0.45: 1.
Preferably, in the step (3), NH in the mixed solution4The mass concentration of Cl is not less than 25 percent, and the excessive concentration easily causes the acetyl glucosamine to be incapable of being hydrolyzed fully, thereby influencing the yield of the glucosamine.
Preferably, in the step (3), the heating temperature is 100-4Cl hydrolysis, and also allows the reaction to be carried out at high temperature and high pressure, accelerating the hydrolysis process and deepening the degree of hydrolysis.
Preferably, in the step (4), the addition amount of the NaOH is determined based on that the pH of the reaction solution after the reaction is completed is alkaline and less than 8; the appropriate excess NaOH not only facilitates the supply of sodium ions for the generation of glucosamine hydrochloride, but also can remove unreacted NH in the hydrolysate4 +Converted into ammonia water and then removed by heating, so that the obtained glucosamine hydrochloride is prevented from containing a large amount of NH4 +。
Preferably, in the step (4), the hydrochloric acid is added in an amount to adjust the pH of the reaction solution to neutral. The excessive sodium hydroxide and 2Na can be reacted by using dilute hydrochloric acid2CO3·3H2O2Decomposed Na2CO3The glucosamine hydrochloride is convenient to generate, and additional impurity ions are avoided from being brought in.
Preferably, in the step (4), the heating temperature is 55-75 ℃. Volatile organic alcohol, ammonia water and other volatile substances in the hydrolysate can be effectively removed through heating, and the purity of the glucosamine hydrochloride is ensured.
Preferably, in the step (5), the drying includes any one of vacuum drying, freeze drying, and the like.
Compared with the prior art, the invention has the following beneficial effects:
(1) the invention adopts 2Na2CO3·3H2O2The thallus in the fermentation liquid is removed, and the advantage of the method is that the cell wall of the thallus can be prevented from being damaged, so that metabolites and the like in the thallus can be prevented from being released to influence the purity and the quality of the product. This is because: 2Na2CO3·3H2O2The microbial biomass is mixed with fermentation liquor and then reacts with water to generate hydroxyl ions which are further converted into active oxygen, the active oxygen acts on the outer surface of the microbial biomass to enable the microbial biomass to lose stability, so that the microbial biomass gradually settles down, floccules are finally formed and separated from the liquid, and the conventional method of heating, inactivating and settling the microbial biomass firstly is easy to break because the microbial biomass is dead, so that metabolites in the microbial biomass are released, and the quality of tracked products is influenced.
(2) In the traditional fermentation process for preparing glucosamine, a large amount of hydrochloric acid is needed for hydrolyzing N-acetylglucosamine, which easily causes environmental pollution and waste acid gas which needs to be treated additionally. The invention adopts NH with the water machine being acidic4Cl replaces hydrochloric acid to carry out the hydrolysis process, and can effectively overcome some problems existing in the traditional fermentation method. In addition, NH4The ammonia water generated by Cl hydrolysis volatilizes from the reaction liquid at high temperature, so that the hydrolysis of ammonium chloride is continuously carried out to generate hydrogen ionThe hydrolysis process is accelerated, and the yield of glucosamine hydrochloride is improved.
(3) According to the invention, volatile organic alcohol such as ethanol is added in the hydrolysis process, and because ammonia water generated at the beginning of steel hydrolysis is not enough to provide a sufficient high-pressure environment, after the volatile organic alcohol such as ethanol is added, a large amount of volatile organic alcohol can be used for creating a high-pressure reaction environment at the initial stage of heating reaction, and ammonia gas can play a role of gradually reinforcing the high-pressure environment after being continuously volatilized along with the gradual progress of the reaction, so that the problem of NH is solved4The hydrogen ions released by Cl consumption are gradually reduced, and the hydrolysis of N-acetylglucosamine is weakened. In addition, volatile organic alcohols and NH4The ammonia gas generated by Cl hydrolysis can not react, and can be easily removed from the hydrolysate by heating, thereby avoiding introducing extra impurity ions as far as possible.
Detailed Description
It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. The invention will now be further illustrated by specific examples.
Example 1
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2According to 2Na in the fermentation liquor2CO3·3H2O2Is mixed according to the concentration of 7.5mg/L, then is mechanically stirred, is stopped stirring when floc is generated, then is kept stand, and is filtered after the floc is not generated any more, so that filtrate is obtained for standby.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution and NH obtained in the step (2)4Placing the mixed solution of the Cl aqueous solution and the ethanol into a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein NH4Mass concentration of Cl 30%, NH4The volume ratio of the Cl aqueous solution to the ethanol is 1: 0.3. And then heating the reaction kettle to 105 ℃ to hydrolyze the acetylglucosamine, so that the reaction is carried out in a high-temperature and high-pressure environment, filtering after the reaction is carried out for 3.5h, and collecting filtrate for later use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 65 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.2, continuously preserving the heat for 20min to separate out substances such as ethanol, ammonia water and the like in the hydrolysate, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain a glucosamine hydrochloride solution for later use.
(5) And (4) carrying out vacuum drying on the glucosamine hydrochloride solution obtained in the step (4) to remove water in the glucosamine hydrochloride solution, thus obtaining glucosamine hydrochloride powder.
Example 2
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2According to 2Na in the fermentation liquor2CO3·3H2O2The concentration of 8.5mg/L, then mechanically stirring, stopping stirring when floc begins to be generated, then standing, and filtering after floc is not generated any more to obtain filtrate for later use.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution and NH obtained in the step (2)4Placing the mixed solution of the Cl aqueous solution and the ethanol into a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein NH4Mass concentration of Cl 35%, NH4The volume ratio of the Cl aqueous solution to the ethanol is 1: 0.35. And then heating the reaction kettle to 100 ℃ to hydrolyze the acetylglucosamine, so that the reaction is carried out in a high-temperature and high-pressure environment, filtering after 4h of reaction, and collecting filtrate for later use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 60 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.5, continuously preserving the heat for 20min to separate out substances such as ethanol, ammonia water and the like in the hydrolysate, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain a glucosamine hydrochloride solution for later use.
(5) And (4) freeze-drying the glucosamine hydrochloride solution obtained in the step (4) to remove water in the solution, thus obtaining glucosamine hydrochloride powder.
Example 3
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2According to 2Na in the fermentation liquor2CO3·3H2O2Is mixed according to the concentration of 6.5mg/L, then is mechanically stirred, is stopped stirring when floc is generated, then is kept stand, and is filtered after the floc is not generated any more, so that filtrate is obtained for standby.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution and NH obtained in the step (2)4Mixing the Cl aqueous solution and the propanol and placingIn a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein NH4Mass concentration of Cl 25%, NH4The volume ratio of the Cl aqueous solution to the propanol was 1: 0.45. And then heating the reaction kettle to 110 ℃ to hydrolyze the acetylglucosamine, so that the reaction is carried out in a high-temperature and high-pressure environment, filtering after the reaction is carried out for 3 hours, and collecting filtrate for later use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 55 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.8, continuously preserving the heat for 30min to separate out propanol, ammonia water and other substances in the hydrolysate, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain a glucosamine hydrochloride solution for later use.
(5) And (4) carrying out vacuum drying on the glucosamine hydrochloride solution obtained in the step (4) to remove water in the glucosamine hydrochloride solution, thus obtaining glucosamine hydrochloride powder.
Example 4
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2According to 2Na in the fermentation liquor2CO3·3H2O2Is mixed according to the concentration of 8mg/L, then mechanical stirring is carried out, the stirring is stopped when the floccule is generated, then the mixture is kept stand, and the filtrate is obtained after the floccule is not generated any more, and is reserved.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution and NH obtained in the step (2)4Placing the mixed solution of the Cl aqueous solution and the ethanol into a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein NH4Mass concentration of Cl 35%, NH4The volume ratio of the Cl aqueous solution to the ethanol is 1: 0.28. And then heating the reaction kettle to 112 ℃ to hydrolyze the acetylglucosamine, so that the reaction is carried out in a high-temperature and high-pressure environment, filtering after the reaction is carried out for 3.5h, and collecting filtrate for later use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 70 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.5, continuously preserving the heat for 20min to separate out substances such as ethanol, ammonia water and the like in the hydrolysate, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain a glucosamine hydrochloride solution for later use.
(5) And (4) freeze-drying the glucosamine hydrochloride solution obtained in the step (4) to remove water in the solution, thus obtaining glucosamine hydrochloride powder.
Example 5
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2According to 2Na in the fermentation liquor2CO3·3H2O2Is mixed according to the concentration of 9mg/L, then mechanical stirring is carried out, the stirring is stopped when the floccule is generated, then the mixture is kept stand, and the filtrate is obtained after the floccule is not generated any more, and is reserved.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution and NH obtained in the step (2)4Placing the mixed solution of the Cl aqueous solution and the methanol into a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein NH4Mass concentration of Cl 30%, NH4The volume ratio of the Cl aqueous solution to the methanol is 1: 0.32. Then heating the reaction kettle to 115 ℃ to obtain the p-acetylglucosamineHydrolyzing sugar to make the reaction proceed in high temperature and high pressure environment, filtering after reacting for 3.5h, and collecting filtrate for use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 75 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.5, continuously preserving the heat for 20min to separate out substances such as methanol, ammonia water and the like in the hydrolysate, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain a glucosamine hydrochloride solution for later use.
(5) And (4) carrying out vacuum drying on the glucosamine hydrochloride solution obtained in the step (4) to remove water in the glucosamine hydrochloride solution, thus obtaining glucosamine hydrochloride powder.
Test example 1
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) and (2) inactivating the thalli by keeping the temperature of the glucosamine fermentation liquor at 85 ℃ for 15min, adding ferric trichloride (a flocculating agent) according to the proportion that the concentration of the ferric trichloride in the fermentation liquor is 7.5mg/L, mechanically stirring, stopping stirring when floccule is generated, standing, filtering after the floccule is not generated any more, and obtaining a filtrate for later use.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution and NH obtained in the step (2)4Placing the mixed solution of the Cl aqueous solution and the ethanol into a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein NH4Mass concentration of Cl 30%, NH4The volume ratio of the Cl aqueous solution to the ethanol is 1: 0.3. And then heating the reaction kettle to 105 ℃ to hydrolyze the acetylglucosamine, so that the reaction is carried out in a high-temperature and high-pressure environment, filtering after the reaction is carried out for 3.5h, and collecting filtrate for later use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 65 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.2, continuously preserving the heat for 20min, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain glucosamine hydrochloride solution for later use.
(5) And (4) carrying out vacuum drying on the glucosamine hydrochloride solution obtained in the step (4) to remove water in the glucosamine hydrochloride solution, thus obtaining glucosamine hydrochloride powder.
Test example 2
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2According to 2Na in the fermentation liquor2CO3·3H2O2Is mixed according to the concentration of 7.5mg/L, then is mechanically stirred, is stopped stirring when floc is generated, then is kept stand, and is filtered after the floc is not generated any more, so that filtrate is obtained for standby.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) And (3) placing the mixed solution of the acetylglucosamine solution obtained in the step (2), the ferric trichloride aqueous solution and the ethanol in a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein the mass concentration of the ferric trichloride is 30%, and the volume ratio of the ferric trichloride aqueous solution to the ethanol is 1: 0.3. And then heating the reaction kettle to 105 ℃ to hydrolyze the acetylglucosamine, so that the reaction is carried out in a high-temperature and high-pressure environment, filtering after the reaction is carried out for 3.5h, and collecting filtrate for later use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 65 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.2, continuously preserving the heat for 20min, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain glucosamine hydrochloride solution for later use.
(5) And (4) carrying out vacuum drying on the glucosamine hydrochloride solution obtained in the step (4) to remove water in the glucosamine hydrochloride solution, thus obtaining glucosamine hydrochloride powder.
Test example 3
A method for preparing glucosamine hydrochloride by using glucosamine fermentation broth comprises the following steps:
(1) mixing the fermentation liquor of glucosamine with 2Na2CO3·3H2O2According to 2Na in the fermentation liquor2CO3·3H2O2Is mixed according to the concentration of 7.5mg/L, then is mechanically stirred, is stopped stirring when floc is generated, then is kept stand, and is filtered after the floc is not generated any more, so that filtrate is obtained for standby.
(2) And (2) filtering the filtrate obtained in the step (1) by adopting a ceramic membrane with the aperture of 40nm to filter macromolecular collagen, pigments and other substances, adding active carbon into the obtained filtrate again to further decolor the filtrate, and filtering the active carbon to obtain the acetylglucosamine solution for later use.
(3) The acetylglucosamine solution and NH obtained in the step (2)4Placing the mixed solution of the Cl aqueous solution into a high-pressure reaction kettle with a polytetrafluoroethylene lining, wherein NH is contained4The mass concentration of Cl was 30%. And then heating the reaction kettle to 105 ℃ to hydrolyze the acetylglucosamine, so that the reaction is carried out in a high-temperature and high-pressure environment, filtering after the reaction is carried out for 3.5h, and collecting filtrate for later use.
(4) And (3) gradually adding NaOH into the filtrate obtained in the step (3), heating the hydrolysate to 65 ℃, detecting the pH of the hydrolysate by using a pH online tester, stopping adding the NaOH when the pH is 7.2, continuously preserving the heat for 20min, and then dropwise adding hydrochloric acid to adjust the pH of the hydrolysate to be neutral to obtain glucosamine hydrochloride solution for later use.
(5) And (4) carrying out vacuum drying on the glucosamine hydrochloride solution obtained in the step (4) to remove water in the glucosamine hydrochloride solution, thus obtaining glucosamine hydrochloride powder.
The purity and yield of glucosamine hydrochloride powders prepared in examples 1 to 5 and test examples 1 to 3 were measured, and the results are shown in tables 1 and 2, respectively.
TABLE 1
|
Example 1
|
Example 2
|
Example 3
|
Example 4
|
Example 5
|
Purity/wt.% of glucosamine hydrochloride
|
99.21
|
98.86
|
99.01
|
98.43
|
99.14
|
Glucosamine hydrochloride yield/%)
|
87.33
|
84.59
|
80.86
|
82.70
|
84.48 |
TABLE 2
|
Test example 1
|
Test example 2
|
Test example 3
|
Purity/wt.% of glucosamine hydrochloride
|
94.39
|
96.55
|
98.94
|
Glucosamine hydrochloride yield/%)
|
86.81
|
73.12
|
54.90 |
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.