Reinforcing method of Arabic gum AGP functional component and Arabic gum product

Abstract

The invention discloses a strengthening method of Arabic gum AGP functional components and an Arabic gum product, and belongs to the technical field of high-molecular compounds, the strengthening method comprises the following steps: adding hydroxypropyl methyl cellulose and Arabic gum into water, fully stirring and uniformly mixing to form a mixed aqueous solution, standing until phase separation is complete, filtering, and drying to obtain the Arabic gum AGP functional components. And collecting an Arabic gum enriched phase. Through liquid-liquid mutual exclusion type phase separation, Arabic gum components are induced to be subjected to graded strengthening, the AGP functional components in the Arabic gum can be increased to 30% or above, and high-valued application is achieved. According to the method, additional chemical reagents or harmful groups do not need to be introduced, natural chemical structures of all components of the Arabic gum are completely reserved, a small amount of HPMC is contained, safety risks are not introduced, and the Arabic gum has high AGP content and rheological properties of HPMC at the same time; a synergistic interaction effect is exerted on the application of the product in the high-added-value fields such as medicines, cosmetics and coatings, and the product performance is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of polymer compounds, and in particular to a method for strengthening functional components of gum arabic gum (AGP) and a gum arabic gum product. Background Art

[0002] Gum Arabic (GA) is a natural plant gum, mainly extracted from the secretions of the trunk of the Arabic tree. It is widely used in many fields such as food, medicine, and cosmetics. The main components of gum Arabic include Arabinogalactan Protein (AGP), polysaccharides and a small amount of protein. Among them, AGP is one of the most important functional components in gum Arabic, with unique emulsification, stabilization and thickening properties.

[0003] However, the content of AGP functional components in existing gum arabic products is usually low, rarely reaching more than 30%. This limitation affects the performance of gum arabic in some high-end applications. Studies have shown that gum arabic with high AGP content has significant advantages such as enhanced emulsification stability and biological activity, excellent rheological properties, etc. For example, gum arabic with high AGP content can more effectively stabilize oil-water emulsions and extend the shelf life of products; it can show excellent thickening and rheological adjustment properties at low concentrations, and is suitable for high-demand food and cosmetic formulations.

[0004] Since gum arabic contains multiple components, such as arabinogalactan (AG) and glycoprotein (GP), which are similar to AGP in structure and properties, there are many problems in the preparation of gum arabic with high AGP content. For example, chemical modification may introduce toxic or harmful chemical groups, affecting the safety and application scope of gum arabic; physical modification may destroy the natural structure of gum arabic and reduce its emulsification properties and stability. Summary of the invention

[0005] In view of the technical problems existing in the prior art, the present invention aims to provide a method for strengthening the AGP functional component of gum arabic. Without changing the physical structure and without introducing toxic and harmful chemical reagents or groups, the gum arabic components are induced to undergo graded strengthening through liquid-liquid mutually exclusive phase separation technology, thereby achieving a significant increase in the AGP content in gum arabic.

[0006] A method for strengthening the functional component of gum arabic (AGP), comprising adding hydroxypropylmethylcellulose (HPMC) and gum arabic into water, stirring and mixing them thoroughly to form a mixed aqueous solution, standing the solution until phase separation is complete, and collecting a gum arabic enriched phase.

[0007] Furthermore, the viscosity of the hydroxypropyl methylcellulose is 100 to 100000 mPa·s.

[0008] Furthermore, the mass concentration of the hydroxypropyl methylcellulose in the mixed aqueous solution is 0.1-2%.

[0009] Furthermore, the mass concentration of gum arabic in the mixed aqueous solution is 2-30%.

[0010] Furthermore, the mass concentration of hydroxypropyl methylcellulose in the mixed aqueous solution is 1%, and the mass concentration of gum arabic is 8%.

[0011] Furthermore, the weight average molecular weight of the hydroxypropyl methylcellulose is 0.73×10 5 ~5.88×10 5 g / mol.

[0012] Furthermore, the ambient temperature during standing until the phase separation is complete is 20-25°C.

[0013] Furthermore, the mass proportion of the AGP component in the gum arabic enriched phase is greater than 30%.

[0014] The present invention also provides a gum arabic product prepared by the method described above, wherein the gum arabic product is the gum arabic enriched phase.

[0015] The present invention has the following beneficial effects:

[0016] 1. The method for strengthening the AGP functional component of gum arabic disclosed in the present invention increases the AGP component in gum arabic to more than 30%, thereby promoting the high-value application of gum arabic.

[0017] 2. The liquid-liquid mutually exclusive phase separation disclosed in the present invention induces graded strengthening of gum arabic components without introducing additional chemical reagents and harmful groups, and at the same time does not make any changes to the natural chemical structure of the various components of gum arabic. It is a new green gum arabic modification technology.

[0018] 3. The gum arabic rich phase obtained by mutually exclusive phase separation of the mixed solution of hydroxypropyl methylcellulose and gum arabic in the present invention also contains a small amount of hydroxypropyl methylcellulose compared with natural gum arabic, which is a safe material widely used in the field of food and medicine, and has excellent hydrophilicity, solubility and film-forming properties. The presence of hydroxypropyl methylcellulose in the gum arabic rich phase not only does not introduce safety risks, but also enables gum arabic to have a high AGP content while having the rheological properties of hydroxypropyl methylcellulose, which plays a synergistic role in its application in high value-added fields such as medicine, cosmetics, coatings, etc., and further improves product performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 Graph showing mutually exclusive phase separation behavior after mixing hydroxypropyl methylcellulose of different viscosities with gum arabic in the embodiments of the present invention (from left to right: Embodiment 1, Embodiment 2 and Embodiment 3).

[0021] Figure 2 This is a graph showing the effect of hydroxypropyl methylcellulose with different viscosities on the molecular weight fractionation of gum arabic analyzed by gel permeation chromatography and multi-angle laser light scattering.

[0022] Figure 3 This is an influence diagram of the AGP component content caused by molecular weight fractionation after mutually exclusive phase separation of hydroxypropyl methylcellulose and gum arabic of different viscosities.

[0023] Figure 4 This is a functional relationship diagram of the steady-state shear viscosity of the gum arabic rich phase after phase separation of hydroxypropyl methylcellulose and gum arabic of different viscosities as a function of shear rate. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] A method for strengthening the functional component of gum arabic (AGP) comprises adding hydroxypropyl methylcellulose and gum arabic into water, fully stirring and mixing to form a mixed aqueous solution, standing until phase separation is complete, and collecting a gum arabic enriched phase.

[0026] Furthermore, the viscosity of the hydroxypropyl methylcellulose is 100 to 100000 mPa·s.

[0027] Furthermore, the mass concentration of the hydroxypropyl methylcellulose in the mixed aqueous solution is 0.1-2%.

[0028] Furthermore, the mass concentration of gum arabic in the mixed aqueous solution is 2-30%.

[0029] Furthermore, the mass concentration of hydroxypropyl methylcellulose in the mixed aqueous solution is 1%, and the mass concentration of gum arabic is 8%.

[0030] Furthermore, the weight average molecular weight of the hydroxypropyl methylcellulose is 0.73×10 5 ~5.88×10 5 g / mol.

[0031] Furthermore, the ambient temperature during the standing until the phase separation is complete is 20-25°C.

[0032] Furthermore, the mass proportion of the AGP component in the gum arabic enriched phase is greater than 30%.

[0033] In this scheme, since gum arabic and hydroxypropyl methylcellulose both have negative charges in the mixed solution, they exhibit thermodynamic incompatibility under the action of steric repulsion or electrostatic repulsion.

[0034] The technical parameters disclosed in the present invention ensure that the mixed concentration of the solution is greater than its critical concentration, so that mutually exclusive phase separation occurs, and the system forms two different enriched phases, wherein the gum arabic enriched phase is enriched with gum arabic, and the content of the arabinogalactan protein (AGP) component that plays a key role in the emulsification performance of gum arabic is greatly increased. The gum arabic enriched phase also contains a small amount of hydroxypropyl methylcellulose.

[0035] The liquid-liquid mutually exclusive phase separation disclosed in the present invention induces graded strengthening of the gum arabic components, but does not change the natural chemical structure of the gum arabic components. It is a new green gum arabic modification technology.

[0036] The present invention also provides a gum arabic product prepared by the method described above, wherein the gum arabic product is the gum arabic enriched phase.

[0037] The gum arabic enriched phase obtained by the present invention, that is, it also contains a small amount of hydroxypropyl methylcellulose compared with natural gum arabic. As a safe material widely used in the fields of food and medicine, it has excellent hydrophilicity, solubility and film-forming properties. Its presence not only does not introduce safety risks, but also can play a synergistic role in high-value applications such as high-AGP content gum arabic as a thickener, emulsifier and stabilizer, thereby further improving product performance.

[0038] Example 1

[0039] 100mPa·s HPMC enriches AGP functional components of gum arabic

[0040] Prepare a 100 mPa·s hydroxypropyl methylcellulose sample and a gum arabic sample, add the hydroxypropyl methylcellulose and the gum arabic to water at room temperature (25°C), stir and mix thoroughly to form a mixed aqueous solution, wherein the mass concentration of the 100 mPa·s hydroxypropyl methylcellulose sample is 1%, and the mass concentration of the gum arabic is 8%. The mixed aqueous solution is allowed to stand for 24 hours until the phase separation is complete, and the gum arabic enriched phase is collected.

[0041] Example 2

[0042] 15000mPa·s HPMC enriched AGP functional components of gum arabic

[0043] Prepare a hydroxypropyl methylcellulose sample with a viscosity of 15000 mPa·s and a gum arabic sample, add hydroxypropyl methylcellulose and gum arabic into water at room temperature (25°C), stir and mix thoroughly to form a mixed aqueous solution, wherein the mass concentration of the hydroxypropyl methylcellulose sample with a viscosity of 15000 mPa·s is 1%, and the mass concentration of the gum arabic is 8%. The mixed aqueous solution is allowed to stand for 24 hours until the phase separation is complete, and the gum arabic enriched phase is collected.

[0044] Example 3

[0045] 100000mPa·s HPMC enriched AGP functional components of gum arabic

[0046] Prepare a hydroxypropyl methylcellulose sample with a viscosity of 100000 mPa·s and a gum arabic sample, add hydroxypropyl methylcellulose and gum arabic into water at room temperature (25°C), stir and mix thoroughly to form a mixed aqueous solution, wherein the mass concentration of the hydroxypropyl methylcellulose sample with a viscosity of 100000 mPa·s is 1%, and the mass concentration of the gum arabic is 8%. The mixed aqueous solution is allowed to stand for 24 hours until the phase separation is complete, and the gum arabic enriched phase is collected.

[0047] Test methods, results and analysis

[0048] (1) Characterization of molecular weight and basic structure of hydroxypropyl methylcellulose and gum arabic

[0049] A 2 mg / mL test solution was prepared and filtered through a 0.2 μm filter membrane before testing. The eluent was a 0.2 mol / L sodium chloride aqueous solution containing 0.005% sodium azide. The molecular weight and basic structure of hydroxypropyl methylcellulose and gum arabic were characterized by gel permeation chromatography and multi-angle laser light scattering (GPC-MALLS). As shown in Table 1, the weight average molecular weight of the whole gum of gum arabic is about 2.8×10 6Da, of which the weight average molecular weight of AGP is about 6.6×10 6 Da, its component accounts for about 27.30%.

[0050] Table 1 Basic parameters of hydroxypropyl methylcellulose and gum arabic with different viscosities

[0051]

[0052] In addition, the data of hydroxypropyl methylcellulose show that the molecular weights of 100mPa·s, 15000mPa·s and 100000mPa·s hydroxypropyl methylcellulose are 7.3×10 4 , 3.33×10 5 and 5.88×10 5 The molecular weight and mean square radius of rotation of HPMC increase significantly with the increase of its viscosity. This characteristic can effectively improve the formation efficiency of the gum arabic rich phase, process stability and product purity in the mutually exclusive phase separation system with gum arabic.

[0053] (2) Molecular weight of gum arabic and AGP components in the gum arabic enriched phase of each example

[0054] Due to thermodynamic instability, the mixed solutions of each embodiment will undergo mutually exclusive phase separation behaviors to varying degrees, such as Figure 1 As shown, after mutually exclusive phase separation between gum arabic and hydroxypropyl methylcellulose, the solution is divided into an upper HPMC-rich phase and a lower gum arabic-rich phase.

[0055] The molecular characteristics, molecular weight changes and AGP content changes of gum arabic in the gum arabic rich phase after phase separation were analyzed by gel permeation chromatography coupled with multi-angle laser light scattering (GPC-MALLS) measurement method.

[0056] Table 2 lists the molecular weights and other characteristics of the control samples and mixed samples of different viscosities in each embodiment. The data show that the degree of phase separation (V U / V L ), the molecular weight of gum arabic in the enriched phase after phase separation and the AGP content therein increased significantly with the increase of the viscosity of hydroxypropyl methylcellulose.

[0057] Table 2 Molecular weight parameters of the Arabic gum-rich phase after phase separation

[0058]

[0059] Specifically, in the system with the highest viscosity of hydroxypropyl methylcellulose at 100,000 mPa·s (Example 3), the molecular weight of gum arabic in the gum arabic rich phase was the highest at 5.81×10 6Da, almost no enrichment modification of gum arabic 2.82×10 6 Da. At the same time, the AGP content in gum arabic increased from 27.3% in the unenriched gum arabic to 36.5% in the 100000 mPa·s hydroxypropyl methylcellulose system of Example 3. After phase separation, the molecular weight of gum arabic in the gum arabic enriched phase and the AGP content therein increased. At the same time, the weight-average molecular weight of AGP did not change significantly, indicating that the molecular weight increase is due to the enrichment of the AGP component rather than a change in the chemical structure.

[0060] (3) Characterization of the molecular weight fractionation of the Arabidopsis-enriched phase in each example

[0061] The components of the gum arabic rich phase in the phase separation mixture of hydroxypropyl methylcellulose and gum arabic of different viscosities were characterized by gel permeation chromatography coupled with differential detection. Figure 2 , Figure 3 As shown in the figure, as the viscosity of HPMC increases from 100mPa·s to 100000mPa·s, the proportion of AGP in the enriched phase increases from 31% to 36.5%. Compared with gum arabic without enriched phase separation, the AGP content increases by up to 9 percentage points, and the AGP content in all examples exceeds 30%, which verifies the selective enrichment ability of this technology for AGP.

[0062] (4) Steady-state shear viscosity changes of the gum arabic rich phase in each example

[0063] The present invention also analyzes the shear viscosity values ​​of the gum arabic before enrichment phase separation and the gum arabic enrichment phase after phase separation. Figure 4 As shown in Figure 5, the rheological properties changed significantly with the change in the viscosity of HPMC. The shear rate values ​​of the phase-separated SGA samples were highly correlated with the viscosity of HPMC, and the flow curves were consistent with shear thinning behavior.

[0064] This indicates that the gum arabic rich phase after phase separation has a high correlation with hydroxypropyl methylcellulose in rheological properties, which is specifically manifested as similar shear thinning behavior. The gum arabic with enhanced AGP content of the present invention not only retains the advantages of natural gum arabic, increases the AGP content, but also has the rheological properties of HPMC, and is suitable for high-end fields such as pharmaceutical sustained-release preparations, cosmetic thickeners, and coating film-forming agents.

[0065] In summary, the present invention provides a green and efficient gum arabic modification technology with the following advantages and effects: First, it is green and efficient, and the graded strengthening of AGP components is achieved through liquid-liquid mutually exclusive phase separation, without the need for chemical modification or introduction of harmful reagents, which meets the requirements of green chemistry; second, it is a high-value application, and the AGP content is increased to more than 30%, which significantly enhances the functionality of gum arabic (such as emulsification stability and film-forming properties), and expands its application scenarios in the fields of medicine, food and industry; third, it is a synergistic effect enhancement, and the trace amount of HPMC contained in the enriched phase can further optimize the rheological properties and form a synergistic effect of the "natural-synthetic" composite material.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for strengthening the functional component of gum arabic AGP, characterized in that: Hydroxypropyl methylcellulose and gum arabic are added to water, and the mixture is stirred thoroughly to form a mixed aqueous solution. The mixture is allowed to stand until the phases are completely separated, and the gum arabic rich phase is collected.

2. The method for strengthening the functional component of gum arabic AGP according to claim 1, characterized in that: The viscosity of the hydroxypropyl methylcellulose is 100 to 100000 mPa·s.

3. The method for strengthening the functional component of gum arabic AGP according to claim 1, characterized in that: The mass concentration of the hydroxypropyl methylcellulose in the mixed aqueous solution is 0.1-2%.

4. The method for strengthening the functional component of gum arabic AGP according to claim 3, characterized in that: The mass concentration of the gum arabic in the mixed aqueous solution is 2-30%.

5. The method for strengthening the functional component of gum arabic AGP according to claim 4, characterized in that: The mass concentration of hydroxypropyl methylcellulose in the mixed aqueous solution is 1%, and the mass concentration of gum arabic is 8%.

6. The method for strengthening the functional component of gum arabic AGP according to claim 2, characterized in that: The weight average molecular weight of the hydroxypropyl methylcellulose is 0.73×10 5 ~5.88×10 5 g / mol.

7. The method for strengthening the functional component of gum arabic AGP according to claim 1, characterized in that: The ambient temperature during the step of standing until the phase separation is complete is 20-25°C.

8. The method for strengthening the functional component of gum arabic AGP according to claim 1, characterized in that: The mass proportion of the AGP component in the gum arabic enriched phase is more than 30%.

9. A gum arabic product prepared by the method for strengthening the functional component of gum arabic AGP according to any one of claims 1 to 8, characterized in that: The gum arabic product is the gum arabic enriched phase.

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