CN1332984C - Method for preparing chitosan/chitose in molecular weight narrow distributed - Google Patents
Method for preparing chitosan/chitose in molecular weight narrow distributed Download PDFInfo
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- CN1332984C CN1332984C CNB2004100398142A CN200410039814A CN1332984C CN 1332984 C CN1332984 C CN 1332984C CN B2004100398142 A CNB2004100398142 A CN B2004100398142A CN 200410039814 A CN200410039814 A CN 200410039814A CN 1332984 C CN1332984 C CN 1332984C
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Abstract
The present invention relates to a method for preparing oligomeric chitosan with narrow molecular weight distribution, which uses a template coordination length control/catalytic oxidation cracking method to prepare oligomeric chitosan with narrow molecular weight distribution. The present invention has the technical scheme that solids of high-poly chitosan are dissolved into solution by edible acetic acid; coordinated polymer particles PACu-CMPS of copper p-dibenzoate (II) solid metal, which is chemically synthesized and is crushed and screened, is stirred and is added into the solution; the pH value is regulated to lead amidogen in the chitosan to form weak coordination bond with metallic ion exposed on the surface of the PACu-CMPS particlesan oxidant added at room temperature is evenly mixed; temperature is raised for degradation; filtered and separated degrading liquid is concentrated at low temperature or at room temperature so as to obtain powder products of solids. The method can conveniently prepare oligomeric chitosan of which the number average molecular weight and the molecular weight distribution range accord with the requirements of specific biologic physiological activity and medical treatment functional food. The oligomeric chitosan with wide application has the efficiency of improving the immunity of animals and plants.
Description
Technical field
The present invention relates to a kind of method for preparing narrow molecular weight distributed Chitosan poly oligosaccharide.
Background technology
The present invention relates to a kind of utilize amino and chemosynthesis in the chitosan to dibenzoic acid copper (II) solid metal coordination polymer particle (be called for short: PACu-CMPS) the surface exposure metal ion combines by weak coordination bond, through add oxidizer catalytic oxidative degradation, filtration, and other aftertreatments preparations be rich in the method for narrow molecular weight distributions oligosaccharide.More specifically saying so goes out the template adsorbing base of dibenzoic acid copper (II) solid metal coordination polymer particle as the absorption chitosan with chemosynthesis, reaches certain particle size through grinding efflorescence.The undissolved PACu-CMPS of slightly acidic joined be dissolved in the plain chitosan aqueous solution after deacetylated of the biological carapace that contains 0.5% acetic acid; with the PACu-CMPS particle surface is matrix; make part in the chitosan amino be exposed to the PACu-CMPS particle surface, free hapto the is arranged metallic ion coordination of (or replacing water molecules), promptly the mode of the metal formation weak coordination bond by amino of chitosan and PACu-CMPS particle surface is adsorbed in tiny PACu-CMPS surface with the chitosan superpolymer.By the distance between the PACu-CMPS particle surface bare metal ion, promptly metal ion is at the equal distribution density of PACu-CMPS stromal surface.Low temperature adds complex-catalyzed oxidation of available metal and responsive to temperature type oxygenant, stirs, and elevated temperature starts catalytic oxidation, near the chitosan of the cracking simultaneously macromolecular chain all metal ions position of PACu-CMPS stromal surface.The size and the range of molecular weight distributions of oligosaccharides number-average molecular weight after distance between each bare metal ion of PACu-CMPS particle surface and the big young pathbreaker of equal distribution density determine to degrade.Because used PACu-CMPS is the slightly acidic insolubles, can product be separated with catalytic matrix by filtering, obtain number-average molecular weight and range of molecular weight distributions through necessary aftertreatment again and meet peculiar bio-physiological activity, medical health care function requirement, improve effects such as animals and plants immunity etc., the oligosaccharide of extensive use is arranged.PACu-CMPS can use repeatedly simultaneously.
At present, the method that domestic and international degradation of chitosan prepares low-molecular water-soluble chitosan mainly contains enzyme liberating method, oxidation degradation method, acid degradation method, secondly also has microwave method, supersonic method, radiation method etc.Existing enzyme liberating method mainly depends on chitoanase, lipase, N,O-Diacetylmuramidase and other non-specificity lytic enzymes, although can single-minded cut-out glycosidic link, the whole piece macromolecular chain is evenly cut to obtain aspect the homogeneous oligosaccharides also powerless.Its mechanism that obtains the oligosaccharides homogeneity is the distribution of enzyme molecule in chitosan solution, and influence factor is a lot.It is reported that this method can obtain six to eight sugar of certain yield, product food and medical aspect (cancer therapy drug) of many uses, but, promptly lack the possibility of carrying out large-scale industrial production with Financial cost selecting suitable enzyme to remain in difficulty to be fit to large-scale industrialization production and effectively to dispel on the technology that mixes enzyme in the degraded after product; And now be used for the oxidation degradation method of the suitability for industrialized production (produce as " treasured of sturgeon " capsule-Shanghai big health biological products company etc.) of chitosan product, comprise H
2O
2Oxidation style, H
2O
2-NaClO
2Method, H
2O
2-HC] method and some other oxidation degradation method.Oxidation style also can obtain the oligosaccharides than narrow molecular weight distributions of molecular weight about 1000 under the condition exacting terms, but at this moment follow the ratio of degraded generation by product monose to increase greatly (1: 1, or more).In addition, this method is to have introduced various reaction reagents in degradation process to the greatest problem that degradation of chitosan exists, and makes to the control of its degraded side reaction and is increasing difficulty aspect the separation and purification of degraded product; The acid degradation method, it comprises HCl edman degradation Edman, acid-nitrite method, peroxyacetic acid method, reaches other acid hydrolyzations.Wherein the molecular weight distribution of the low-molecular water-soluble chitosan-hydrochloride that obtains with the HCl edman degradation Edman compares broad, but there is report can prepare relatively slightly high-load 12 to 19 (molecular weight is at 2000-3000, and it is narrow relatively to distribute) low-molecular water-soluble chitosan with acid-nitrite method.Acid hydrolyzation and simple oxidation degradation method all are nonspecific degradation processes, the difficult control of its degradation process, though successively be used for suitability for industrialized production, and the chitosan product of various molecular weight ranges can both obtain, but will expect the specified molecular weight scope and have higher yields and chitosan product that can widespread use difficulty relatively then; Other edman degradation Edmans such as microwave method, supersonic method, radiation method etc. also can obtain low-molecular water-soluble chitosan, but still belong to non-specific degradation process, still belong to the fundamental research exploratory stage at present.This shows that the product that all non-specific degradation process degradeds obtain all has a same insurmountable difficult problem: molecular-weight average distributes wide.
Summary of the invention
The purpose of this invention is to provide a kind of method for preparing narrow molecular weight distributed Chitosan poly oligosaccharide.What this method was avoided adopting in the present industrial production is all drawbacks and the deficiency that the preparation low-molecular water-soluble chitosan process of mechanism is shown with non-specific degradation process, and a kind of atmosphere of artificial manufacturing specificity degraded is provided.Product can be isolated by filtering, the purpose that makes preparation obtain the narrow molecular weight distributions oligosaccharides is achieved eventually.
The objective of the invention is to be achieved through the following technical solutions:
[1]. the present invention utilizes the template adsorbing base to dibenzoic acid copper (II) solid metal coordination polymer particle (PACu-CMPS) conduct absorption chitosan of chemosynthesis, to be dissolved in the high molecular weight chitosan absorption and the stromal surface of weakly acidic solution, the pH value of regulation system, amino in the chitosan is combined with stromal surface bare metal ion coordination, add oxygenant, being 0-100 ℃ in temperature is to stir under the condition of 3-7 with the pH value, degrade chitosan in 1 minute to 72 hours time range obtains the narrow molecular weight distributions oligosaccharides.
[2]. the method in the scheme [1], use therein raw materials of chitosan are one of the main extract of shrimp, crab shell and insect, algae and bacterium generation from aquaculture, the marine organisms deacetylated products of chitin.
[3]. the method in the scheme [1] is wherein as follows as the solid metal coordination high polymer compounds process for production thereof of matrix:
Take by weighing terephthalic acid 16.8g and put into stirring tank, add 15cm
3Deionized water is wetting, drips 1%NaOH (weight ratio) under the agitation condition in stirring tank, just dissolves to terephthalic acid, filter, filtrate add again 36% acetate to precipitation fully, suction strainer, filter cake is washed washing 3 times with deionized water.With slowly adding 1%NaOH (weight ratio) filter cake is just dissolved, in the terephthalic acid ammonia soln, add 40 grams, one water acetic acid copper, stirred 0.5-6 hour, the back drips 36% acetate to precipitation and separates out, suction strainer, filter cake moves in the Glass Containers after washing three times with 0.5% acetic acid, add strong aqua to container and make the filter cake dissolving, seal (staying a spilehole), room temperature was placed 1-15 days, separate out particular design and synthetic to dibenzoic acid copper (II) solid metal coordination polymer crystal grain (PACu-CMPS).
[4]. the preparation method in the scheme [3], wherein relating to all raw materials of synthetic and reagent is commercially available technical pure or the higher purity grade of purity.
[5]. the preparation method in the scheme [3], obtain to dibenzoic acid copper (II) solid metal coordination polymer crystal (PACu-CMPS) again drying, grind to collect 50-250 purpose particle, dry back is standby.
[6]. the described method in one of scheme [1] and [2] is characterized in that 0.1-100 is restrained the 10-400cm that the exsiccant chitosan joins 0.1-10% (weight ratio)
3In the aqueous acetic acid, under 0-100 ℃ temperature, the high-molecular weight chitosan is dissolved through 20 minutes-48 hours.
[7]. the method for scheme [1]-[6], it is characterized in that wherein PACu-CMPS is when adding the chitosan aqueous acetic acid, add-on is the 1-80 gram.
[8]. the described method of one of scheme [7], it is characterized in that in system adding medical hydrogen peroxide (commercially available 30%, the weight ratio) oxygenant of the 0.01-25% (weight ratio) of chitosan dosage, under 0-100 ℃ of temperature, stir degraded.
[9]. the method for scheme [8] is characterized in that wherein oxygenant is hydrogen peroxide, dioxide peroxide, oxalic acid, sodium oxalate, hypochlorous acid, clorox, Periodic acid, perchloric acid and using with of different ratios each other thereof.
The technical process of PACu-CMPS template of the present invention absorption control length/catalytic oxidation cracking method can be sketched and is: dissolving high chitosan solid with the edible acetic acid of 0.5-1.0% becomes solution, add the PACu-CMPS particulate stirring of chemosynthesis and crushing screening in the above-mentioned solution down, regulating the pH value makes amino and PACu-CMPS particle surface bare metal ion in the chitosan have weak coordination bond to form, room temperature adds oxygenant and mixes, degraded heats up, filter to isolate degradation solution, low temperature or room temperature concentrate and obtain solid phase prod; Again just use after filter residue washing, the drying.
Principle of the present invention is: make dissolving chitosan macromolecular chain be adsorbed in insoluble micron order PACu-CMPS surface in the weakly acidic water solution, heightening pH value makes the amino metal ion with the PACu-CMPS surface exposure of the part in the polymer chitosan form weak coordination bond again, low temperature adds has the oxygenant of coordination ability also to be adsorbed in the bare metal ion surface, heating up starts Fenton reaction generation hydroxyl radical free radical, presses Fenton reaction mechanism catalytic oxidative cracking polysaccharide chain from these haptos.Add entry and make the product oligosaccharides after the degraded soluble in water, filtering separation is collected solution, concentrates, obtains narrow molecular weight distributed Chitosan poly oligosaccharide product (as number-average molecular weight 5200, dispersion index 1.86, the scope intensive amount reaches more than 80%).Want to reach this purpose, must in preparation process, accurately hold each preparation each details in link, and PACu-CMPS template absorption control length/catalytic oxidative cracking method to need the deacetylation of chitosan be more than 70%.Through exploring repeatedly, optimized the characteristic of each step of degradation process, obtained reliable parameter, degraded is simple and easy to do with purification step.
Owing to adopted technique scheme, PACu-CMPS template absorption control length/catalytic oxidation cracking method of the present invention has following excellent characteristics:
What 1, avoided adopting in the present industrial production on principle is all drawbacks and the deficiency of mechanism with non-specific degradation process, artificial manufacturing the atmosphere of specificity degraded.
2, can pass through filtering separation degraded product chitosan oligomer, method is easy, and is easy to operate.
3, selected raw material reagent is cheap and easy to get, and products obtained therefrom is stable in actual applications, reliable.
4, PACu-CMPS matrix can be used repeatedly, saves material.
5, required production unit is simple, easily satisfies different suitability for industrialized production in batches.
Embodiment
For principle, process and the result of PACu-CMPS template absorption control length/catalytic oxidation cracking method of the present invention further are described, now described in detail with embodiment.
Take by weighing chitosan 50 grams and put into the reactor of belt stirrer, add 4000cm
30.5% acetic acid stirred 60 minutes, made the chitosan dissolving.Take by weighing 5 grams and grind the 100 order PACu-CMPS that sieve, add in the reactor after the water-wet, stir.Na with 5%
2CO
3Regulating the pH value is 6.5.Add 100cm
330% hydrogen peroxide, stirring at room 80 minutes, be heated to 65 ℃ (± 1 ℃) reaction 4 hours.Stir and add 1000cm down
30.05 acetic acid aqueous solution, suction strainer washing 3 times, filtrate normal temperature or be refrigerated to dried.Product HAc-NH
4The dissolving of Ac (pH=4.5) damping fluid, and use HAc-NH
4Ac makes moving phase, and the molecular weight that provides with Sigma company is that 2500,7100,21400,41100,84400 and 133800 water-soluble glucan standard specimens are made typical curve, and regression coefficient is 0.9966.Detecting the mean number average molecular weight that shows degraded Chitosan poly oligosaccharide product through water-soluable gel high performance liquid chromatography (GFC) is 5200, and molecular weight distributing index is 1.82.Being worth indicated is that dried this product still is not soluted in water, and only is dissolved in weakly acidic water solution.Product after the freezing or drying at room temperature dissolves the molecular weight parameter that detects the back does not once more have obvious variation.
Claims (6)
1, a kind of method for preparing narrow molecular weight distributed Chitosan poly oligosaccharide, it is characterized in that: with chitosan is basic parent, its can with the coordination when the pH value 5-7 of template stromal surface metal ion, template matrix be meant chemosynthesis after grind efflorescence reach certain particle size to dibenzoic acid copper II solid metal coordination polymer particle PACu-CMPS, by the mean length between the PACu-CMPS surface metal ion apart from Chitosan poly oligosaccharide behind the control degradation; With the PACu-CMPS particle be dissolved in the high molecular weight chitosan mixed at room temperature of the biological chitin that contains 0.5% acetum after deacetylated, the weight ratio that adds PACu-CMPS is the 25-250% of chitosan, regulating the pH value is 4-7, add an amount of oxygenant, stir, elevated temperature starts catalytic oxidation to 40-100 ℃, keeps under this temperature and stirs 10 minutes-72 hours; Filter; Collect filtrate, obtaining the mean number average molecular weight is 5200, and molecular weight distributing index is 1.82 Chitosan poly oligosaccharide product; Template matrix PACu-CMPS particle can use repeatedly.
2, method according to claim 1 is characterized in that: employed chitosan is the deacetylated product by the chitin that extracts in shrimp shell, crab shell, insect, algae or the bacterium.
3, method according to claim 1 is characterized in that: wherein the synthetic method of PACu-CMPS is:
Take by weighing terephthalic acid 16.8g and put into stirring tank, add 15cm
3Deionized water is wetting, and dripping weight ratio under the agitation condition in stirring tank is 1%NaOH, just dissolves to terephthalic acid, filter, filtrate add again 36% acetate to precipitation fully, suction strainer, filter cake is with deionized water wash 3 times; Slowly adding weight ratio again is 1%NaOH, make the filter cake dissolving, add 40g one water acetic acid copper in the terephthalic acid ammonia soln, stirred 0.5-6 hour, the back drips 36% acetate to precipitation and separates out, suction strainer, filter cake moves in the Glass Containers with after the 0.5% acetic acid washing three times, adds strong aqua to container and makes the filter cake dissolving, stays a spilehole and seals, room temperature was placed 1-15 days, separated out dibenzoic acid copper II solid metal coordination polymer crystal grain PACu-CMPS; Wherein relating to all raw materials of synthetic and reagent is commercially available technical pure grade or the higher purity grade of purity.
4, method according to claim 3 is characterized in that: synthetic PACu-CMPS is drying and grinding again, collects 50-250 purpose particle, and dry back is standby.
5, method according to claim 1 is characterized in that: the oxygenant that adds the 0.01-70% weight ratio of chitosan dosage in system.
6, method according to claim 5 is characterized in that: use therein oxygenant is hydrogen peroxide, dioxide peroxide, oxalic acid, sodium oxalate, hypochlorous acid, clorox, Periodic acid or perchloric acid.
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CN100447162C (en) * | 2005-05-16 | 2008-12-31 | 海南大学 | Method of PACu-A5 adsorption microwave assistant degradation for preparing narrow molecular weight distributed Chitosan poly oligosaccharide |
CN102814165B (en) * | 2012-09-10 | 2014-09-17 | 南昌航空大学 | Method for improving chitosan acidoresistance |
CN103848927B (en) * | 2012-12-05 | 2016-04-13 | 浙江省农业科学院 | The needle mushroom dreg after extracting polysaccharide is utilized to prepare the method for β-chitin |
CN105085711B (en) * | 2015-08-21 | 2018-02-02 | 哈尔滨工业大学 | A kind of preparation method and applications of chitosan oligosaccharide |
CN107987183B (en) * | 2017-12-31 | 2021-02-02 | 浙江工业大学 | Method for extracting chitosan oligosaccharide from filamentous fungi |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1302809A (en) * | 2000-01-05 | 2001-07-11 | 中国科学院大连化学物理研究所 | Process for preparing chitoligose by coupling enzyme degradation of chitosan with membrane separation |
CN1318567A (en) * | 2000-04-17 | 2001-10-24 | 武汉大学 | High concentration process of preparing water soluble oligomerized chitosan |
KR20020046675A (en) * | 2000-12-15 | 2002-06-21 | 조 정 래 | Process for Producing Chitooligosaccharide by Chitosanase that Secreted from Bacillus sp HSB-21 |
CN1401652A (en) * | 2001-08-14 | 2003-03-12 | 华东理工大学 | Process for industrial production of oligochitose and chitooligose |
KR20040006161A (en) * | 2002-07-11 | 2004-01-24 | 주식회사 건풍바이오 | The chitin/chitosan oligosaccharide which mitigating the cold symptoms of hands and foot |
KR20040018890A (en) * | 2002-08-27 | 2004-03-04 | 최종욱 | The method of manufacturing chitin oligoer powder and food composition comprising chitin oligomer powder for improving liver activity |
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Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1302809A (en) * | 2000-01-05 | 2001-07-11 | 中国科学院大连化学物理研究所 | Process for preparing chitoligose by coupling enzyme degradation of chitosan with membrane separation |
CN1318567A (en) * | 2000-04-17 | 2001-10-24 | 武汉大学 | High concentration process of preparing water soluble oligomerized chitosan |
KR20020046675A (en) * | 2000-12-15 | 2002-06-21 | 조 정 래 | Process for Producing Chitooligosaccharide by Chitosanase that Secreted from Bacillus sp HSB-21 |
CN1401652A (en) * | 2001-08-14 | 2003-03-12 | 华东理工大学 | Process for industrial production of oligochitose and chitooligose |
KR20040006161A (en) * | 2002-07-11 | 2004-01-24 | 주식회사 건풍바이오 | The chitin/chitosan oligosaccharide which mitigating the cold symptoms of hands and foot |
KR20040018890A (en) * | 2002-08-27 | 2004-03-04 | 최종욱 | The method of manufacturing chitin oligoer powder and food composition comprising chitin oligomer powder for improving liver activity |
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