A guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative and its preparation method and application

Abstract

The present invention relates to daily chemical and pharmaceutical industries, and in particular to a guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative, a preparation method and application thereof. The chemical structural formula of the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative is as follows. The guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative prepared by the present invention has good antioxidant activity and can be used to prepare antioxidants. The preparation method of the present invention is simple and efficient, enhances the biological activity of chitosan, expands the application range of chitosan, and can be widely used in cosmetics, functional foods and pharmaceutical fields.

Description

Technical Field

[0001] The invention relates to daily chemical and pharmaceutical industries, and in particular to a guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative, and a preparation method and application thereof. Background Art

[0002] Chitosan is a natural high molecular polymer obtained by deacetylation of chitin, which is mainly composed of linear polymerization of acetylamino-D-glucose through β-(1,4)-glycosidic bonds. Chitosan itself has many excellent properties such as antibacterial, antioxidant, non-toxic, biocompatible and biodegradable, and has broad application potential in agriculture, medicine, food, cosmetics and other fields. However, chitosan has poor water solubility and relatively weak biological activity, which limits its further commercial application. However, chitosan is abundant in source and has modifiable hydroxyl, amino and other groups. Therefore, active group coupling and molecular structure modification methods can be used to construct a new system of chitosan derivatives with enhanced activity and diverse structures.

[0003] Carboxymethyl chitosan quaternary ammonium salt is a chemically modified product of chitosan. It mainly introduces carboxymethyl and quaternary ammonium salt groups on the hydroxyl and amino groups of the chitosan molecular chain to give chitosan extremely strong ionic properties and improve its water solubility and biological activity. However, the structure of the modified product is single and the activity improvement is limited, which limits the application of chitosan derivatives in daily chemicals and pharmaceutical fields. The presence of carboxymethyl groups enables the derivative to access new functional groups through ion exchange methods to further regulate its properties and functions, thereby realizing the commercial application value of chitosan. Summary of the invention

[0004] The purpose of the present invention is to provide a guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative and a preparation method and application thereof.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative, the chemical structural formula of the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative is: Formula 1, where R + for , , ;

[0007] The average value range of n is 5-12000.

[0008] A method for preparing the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives,

[0009] Firstly, chitosan is used as a raw material to react with chloroacetic acid to obtain a carboxymethyl chitosan intermediate, and then sodium iodide is used as a catalyst to react with a nucleophilic agent methyl iodide under alkaline conditions to obtain a carboxymethyl chitosan quaternary ammonium salt, and finally an active guanidine salt is introduced into the carboxymethyl chitosan quaternary ammonium salt through an ion exchange reaction to obtain a guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative shown in formula 1.

[0010] Specifically:

[0011] (1) Preparation of carboxymethyl chitosan: chitosan was uniformly dispersed in isopropanol, and a 40% NaOH solution was slowly added dropwise, and stirred at 50-60°C for 1 h. Then, a chloroacetic acid aqueous solution was added to the system, and the reaction was stirred at 50-60°C for 4 h. After the reaction was completed, anhydrous ethanol was used for precipitation, and carboxymethyl chitosan was obtained after freeze-drying.

[0012] (2) Preparation of carboxymethyl chitosan quaternary ammonium salt: carboxymethyl chitosan was uniformly dispersed in 1-methyl-2-pyrrolidone, sodium iodide, sodium hydroxide solution and methyl iodide were added in sequence under stirring at room temperature, refluxed at 60°C for 2 h, and then excess ethanol was added for precipitation. After washing and filtration, carboxymethyl chitosan quaternary ammonium salt was obtained;

[0013] (3) Preparation of guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives: After dissolving the carboxymethyl chitosan quaternary ammonium salt obtained in the above step (2) in deionized water, different guanidine salts were added respectively and stirred at room temperature for 12 hours. After dialysis and freeze-drying, the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives were obtained.

[0014] The guanidine salt in step (3) is guanidine hydrochloride, aminoguanidine hydrochloride or 1,3-diaminoguanidine hydrochloride.

[0015] In step (1), the amount of isopropanol used is 10-12 mL per 1 g of chitosan, the amount of NaOH solution used is 3-4 mL per 1 g of chitosan, the molar ratio of chloroacetic acid to chitosan is (1-2):1, and the amount of anhydrous ethanol used is 150-200 mL per 1 g of chitosan;

[0016] In step (2), the amount of 1-methyl-2-pyrrolidone used is 30-40 mL per 1 g of carboxymethyl chitosan, and the amount of sodium iodide, sodium hydroxide, and methyl iodide used is 1.5-2 g of sodium iodide, 20-30 mmol of sodium hydroxide, and 5-7 mL of methyl iodide per 1 g of carboxymethyl chitosan;

[0017] The amount of deionized water used in step (3) is 20-30 mL per 1 g of carboxymethyl chitosan quaternary ammonium salt, and the molar ratio of the carboxymethyl chitosan quaternary ammonium salt to the guanidine salt is 1:1.

[0018] In step (3), the solution is added to a dialysis bag with a molecular weight cutoff of 10,000, and the dialysis is stirred for 48 hours to remove the residual reagents of the reaction, thereby completing the dialysis.

[0019] An application of the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives, and an application of the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives in the preparation of antioxidants.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) Compared with chitosan, the compounds of the present invention not only enhance the water solubility and biological activity of chitosan, but also improve the reactivity of chitosan after the introduction of carboxymethyl and quaternary ammonium salt groups, so that high-activity guanidine salt groups can be introduced through a simple ion exchange reaction to obtain a new derivative with further enhanced biological activity.

[0022] (2) The quaternary ammonium salt derivatives of chitosan containing guanidine groups prepared by the present invention not only have the advantages of chitosan such as biocompatibility and degradability, but also the presence of carboxylmethyl, quaternary ammonium salt and guanidine salt groups improves its biological activity, such as antioxidant activity.

[0023] (3) The synthesis steps of the present invention are simple, the required equipment and raw materials are easily available, the cost is low, it is easy to promote, and the product yield is high, which can reach more than 60%. The products obtained by the present invention can be widely used in the fields of biology, medicine, cosmetics, food, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is the NMR carbon spectrum of chitosan;

[0025] Figure 2 This is the carbon NMR spectrum of the carboxymethyl chitosan prepared in Example 1 of the present invention;

[0026] Figure 3 The NMR carbon spectrum of the carboxymethyl chitosan quaternary ammonium salt prepared in Example 1 of the present invention;

[0027] Figure 4 The NMR carbon spectrum of the quaternary ammonium salt of guanidine-containing carboxymethyl chitosan prepared in Example 1 of the present invention;

[0028] Figure 5 This is the NMR carbon spectrum of the aminoguanidine carboxymethyl chitosan quaternary ammonium salt prepared in Example 2 of the present invention;

[0029] Figure 6 This is the NMR carbon spectrum of the diaminoguanidine carboxymethyl chitosan quaternary ammonium salt prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the embodiments and drawings, but the present invention is not limited thereto, and any equivalent replacements in the art made according to the disclosure of the present invention belong to the protection scope of the present invention.

[0031] The invention improves the water solubility and antioxidant activity of chitosan by introducing carboxymethyl groups, quaternary ammonium salt groups and guanidinium ions, provides a new idea for the research of chitosan derivatives as antioxidants, and lays a theoretical foundation for their high-value applications in the fields of food, medicine, cosmetics, etc. Example 1

[0032] The synthetic route of guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives is as follows: ;

[0033] Wherein R is guanidine, aminoguanidine or diaminoguanidine, and the average value range of n is 5-12000.

[0034] In this example, the target compound, a guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative, was synthesized according to the above synthesis route.

[0035] (1) Preparation of carboxymethyl chitosan: Weigh 1 g of chitosan (see Figure 1 ) was uniformly dispersed in 10 mL of isopropanol, 3 mL of 40% NaOH solution was slowly added dropwise, and the reaction was stirred at 60 ° C for 1 h. Then 0.88 g of chloroacetic acid was weighed and dissolved in 5 mL of water to obtain a chloroacetic acid aqueous solution, which was slowly added dropwise to the chitosan isopropanol solution, and the reaction was continued at 60 ° C for 4 h. After the reaction was completed, it was poured into excess ethanol. The precipitate was freeze-dried to obtain carboxymethyl chitosan (see Figure 2 );

[0036] (2) Preparation of carboxymethyl chitosan quaternary ammonium salt: weigh 1 g of carboxymethyl chitosan and evenly disperse it in 30 mL of 1-methyl-2-pyrrolidone. Add 1.5 g of sodium iodide, 20 mL of 15% sodium hydroxide solution and 5 mL of methyl iodide in sequence under stirring at room temperature. Reflux at 60 °C for 2 h. Then, add excess ethanol for precipitation. After washing and filtration, carboxymethyl chitosan quaternary ammonium salt is obtained (see Figure 3 );

[0037] (3) Preparation of guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative: Weigh 1 g of carboxymethyl chitosan quaternary ammonium salt and dissolve it in 20 mL of deionized water. Then add 0.59 g of guanidine hydrochloride and stir at room temperature for 12 h. Put the above reaction system into a dialysis bag and dialyze it in deionized water for 48 h. The resulting solution is dried in a vacuum freeze dryer to obtain a guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative (see Figure 4 ), wherein R is a guanidine cation and n is 5-12000.

[0038] Figure 1 This is the NMR carbon spectrum of chitosan. The chemical shift of the polysaccharide skeleton carbon in the chitosan molecule is mainly distributed between δ56-100 ppm, among which the signal peaks at δ100 ppm, δ70-78 ppm, δ61 ppm and δ56 ppm belong to the chemical shifts of [C1], [C3]-[C5], [C6] and [C2] respectively.

[0039] Figure 2 The carbon NMR spectrum of the carboxymethyl chitosan prepared in Example 1 of the present invention shows that after the carboxymethyl group is connected, the carbon NMR spectrum of the product shows chemical characteristic shifts of the carbon on the methylene group connected to the carbonyl group at δ179ppm and δ69ppm, respectively, which proves that the carboxymethyl chitosan is successfully prepared.

[0040] Figure 3 The NMR carbon spectrum of the carboxymethyl chitosan quaternary ammonium salt prepared in Example 1 of the present invention shows that, compared with carboxymethyl chitosan, the product has a new shift at δ54ppm, which corresponds to the characteristic absorption of three methyl groups in the quaternary ammonium salt group, thus proving the successful preparation of the carboxymethyl chitosan quaternary ammonium salt.

[0041] Figure 4 The NMR carbon spectrum of the quaternary ammonium salt of carboxymethyl chitosan containing guanidine groups prepared in Example 1 of the present invention shows that the product has a significant characteristic peak at δ158ppm, which is attributed to the chemical shift of C=N in the guanidine group. In addition, the characteristic shifts of the carboxymethyl group and the quaternary ammonium group still exist, proving that the quaternary ammonium salt of carboxymethyl chitosan containing guanidine groups is successfully prepared. Example 2

[0042] The difference from Example 1 is that:

[0043] (1) Preparation of carboxymethyl chitosan: Weigh 1 g of chitosan and evenly disperse it in 10 mL of isopropanol, slowly drop 3 mL of 40% NaOH solution, stir and react at 60°C for 1 h, then weigh 0.59 g of chloroacetic acid and dissolve it in 5 mL of water to obtain a chloroacetic acid aqueous solution, and slowly drop it into the chitosan isopropanol solution, continue heating and stirring at 60°C for 4 h, pour into excess ethanol after the reaction, and freeze-dry the resulting precipitate to obtain carboxymethyl chitosan;

[0044] (2) Preparation of carboxymethyl chitosan quaternary ammonium salt: weigh 1 g of carboxymethyl chitosan and evenly disperse it in 35 mL of 1-methyl-2-pyrrolidone. Add 1.75 g of sodium iodide, 25 mL of 15% sodium hydroxide solution and 6 mL of methyl iodide in sequence under stirring at room temperature. Reflux at 60 °C for 2 h. Then, add excess ethanol for precipitation. After washing and filtration, carboxymethyl chitosan quaternary ammonium salt was obtained.

[0045] (3) Preparation of aminoguanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative: Weigh 1 g of carboxymethyl chitosan quaternary ammonium salt and dissolve it in 25 mL of deionized water. Then add 0.69 g of aminoguanidine hydrochloride and stir at room temperature for 12 h. Put the above reaction system into a dialysis bag and dialyze it in deionized water for 48 h. The resulting solution is dried in a vacuum freeze dryer to obtain an aminoguanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative (see Figure 5 ), wherein R is an aminoguanidine cation and n is 5-12000.

[0046] Figure 5 The NMR carbon spectrum of the aminoguanidine-containing carboxymethyl chitosan quaternary ammonium salt prepared in Example 2 of the present invention shows that the product has a significant characteristic peak at δ159ppm, which is attributed to the chemical shift of C=N in the aminoguanidine salt group. In addition, the characteristic shifts of the carboxymethyl group and the quaternary ammonium salt group still exist, proving that the aminoguanidine-containing carboxymethyl chitosan quaternary ammonium salt is successfully prepared. Example 3

[0047] The difference from Example 1 is that:

[0048] (1) Preparation of carboxymethyl chitosan: weigh 1 g of chitosan and evenly disperse it in 10 mL of isopropanol, slowly drop 3 mL of 40% NaOH solution, stir and react at 50°C for 1 h, then weigh 1.17 g of chloroacetic acid and dissolve it in 5 mL of water to obtain a chloroacetic acid aqueous solution, and slowly drop it into the chitosan isopropanol solution, continue heating and stirring at 50°C for 4 h, pour into excess ethanol after the reaction, and freeze-dry the resulting precipitate to obtain carboxymethyl chitosan;

[0049] (2) Preparation of carboxymethyl chitosan quaternary ammonium salt: weigh 1 g of carboxymethyl chitosan and evenly disperse it in 40 mL of 1-methyl-2-pyrrolidone. Add 2 g of sodium iodide, 30 mL of 15% sodium hydroxide solution and 7 mL of methyl iodide in sequence under stirring at room temperature. Reflux at 60 °C for 2 h. Then, add excess ethanol for precipitation. After washing and filtration, carboxymethyl chitosan quaternary ammonium salt was obtained.

[0050] (3) Preparation of diaminoguanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative: Weigh 1 g of carboxymethyl chitosan quaternary ammonium salt and dissolve it in 30 mL of deionized water. Then add 0.78 g of 1,3-diaminoguanidine hydrochloride and stir at room temperature for 12 h. Put the above reaction system into a dialysis bag and dialyze it in deionized water for 48 h. The resulting solution is dried in a vacuum freeze dryer to obtain a diaminoguanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative (see Figure 6 ), wherein R is a 1,3-diaminoguanidine cation and n is 5-12000.

[0051] Figure 6The NMR carbon spectrum of the quaternary ammonium salt of diaminoguanidine carboxymethyl chitosan prepared in Example 3 of the present invention shows that the product has a significant characteristic peak at δ160ppm, which is attributed to the chemical shift of C=N in the diaminoguanidine salt group. In addition, the characteristic shifts of the carboxymethyl group and the quaternary ammonium salt group still exist, proving that the quaternary ammonium salt of diaminoguanidine carboxymethyl chitosan is successfully prepared.

[0052] Application Examples

[0053] Antioxidant activity assay

[0054] (1) Determination of reducing ability: The reducing abilities of the compounds of formula 1 finally obtained in Examples 1 to 3, as well as the raw material chitosan of each step of Example 1, and the intermediate products carboxymethyl chitosan and carboxymethyl chitosan quaternary ammonium salt were determined and compared (Table 1): After the samples were freeze-dried to constant weight, they were diluted with deionized water, and 1.0 mL of sample solutions with concentrations of 0.60, 1.20, 2.40, 4.80, and 9.60 mg / mL were prepared in 5 mL test tubes. Then, 1.0 mL of 1% (w / v) potassium ferrocyanide solution was added to the test tubes containing sample solutions of different concentrations, and after being shaken thoroughly to mix evenly, the mixture was reacted at 50°C for 20 min, and the reaction was terminated in an ice water bath. Next, 1.0 mL of 10% (w / v) trichloroacetic acid solution was added, mixed evenly, and centrifuged. Finally, accurately draw 1.5mL of supernatant, add 1.2mL of deionized water and 0.3mL of 0.1% (w / v) ferric chloride solution in turn, react for 10min at room temperature and measure the absorbance at 700nm. Set three parallels for each group and calculate the average value. The larger the absorbance value, the stronger the sample reduction ability. The test results are shown in Table 1.

[0055] Table 1 Absorbance values ​​of chitosan, carboxymethyl chitosan, carboxymethyl chitosan quaternary ammonium salt and guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives

[0056]

[0057] (2) Determination of the ability to scavenge hydroxyl radicals: The scavenging ability of the experimental chitosan, the prepared carboxymethyl chitosan, the carboxymethyl chitosan quaternary ammonium salt and the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives in Examples 1 to 3 was determined and compared (Table 2): First, the samples were vacuum freeze-dried to constant weight, 20 mg of each was accurately weighed, and 2 mL of deionized water was added to dissolve to prepare a sample stock solution with a concentration of 10 mg / mL. Then, 11.3, 22.5, 45, 90, and 180 μL of the sample stock solution were measured in a test tube, and water was added to 1 mL. Then, 0.5 mL of ETA-Fe solution, 1 mL of phosphate buffer, 1 mL of saffron red T solution, and 1 mL of hydrogen peroxide solution were added in sequence. The final concentrations of the sample solutions were 0.025, 0.05, 0.1, 0.2, and 0.4 mg / mL, respectively. At the same time, 1 mL of deionized water was used to replace the sample as a blank group, and 1 mL of deionized water and 1 mL of phosphate buffer were used to replace the sample and hydrogen peroxide solution as a control group. After the reaction system was stoppered and shaken evenly, it was reacted in a 37°C water bath for 30 minutes. After the reaction was completed, it was put into ice water to quench the reaction, and the absorbance of 4.5 mL of the reaction solution was tested and recorded at a wavelength of 520 nm. The samples were measured three times, and the average value was taken to calculate the scavenging ability of hydroxyl free radicals. Scavenging ability of hydroxyl free radicals (%) = (A 样品 -A 空白 ) / (A 对照 -A 空白 ) × 100. The results are shown in Table 2.

[0058] Table 2 Hydroxyl radical scavenging ability of chitosan, carboxymethyl chitosan, carboxymethyl chitosan quaternary ammonium salt and guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives (%)

[0059]

[0060] As shown in Table 1 and Table 2, the antioxidant capacity of the quaternary ammonium salt derivatives of carboxymethyl chitosan containing guanidine groups and carboxymethyl chitosan quaternary ammonium salt synthesized by the present invention is significantly better than chitosan and carboxymethyl chitosan, and shows a certain antioxidant law, namely: diaminoguanidine carboxymethyl chitosan quaternary ammonium salt> aminoguanidine carboxymethyl chitosan quaternary ammonium salt> guanidine carboxymethyl chitosan quaternary ammonium salt> carboxymethyl chitosan> chitosan. The above conclusions show that the quaternary ammonium salt group is the key to improving the antioxidant activity of the product, and the presence of the guanidine salt group can further improve its biological activity, and the improvement strength is related to the electron-withdrawing ability of the guanidine salt compound. The stronger the electron-withdrawing ability, the stronger the antioxidant capacity of the product.

Claims

1. A guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative, characterized in that: The chemical structural formula of the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives is: Formula 1, where R + for , , ; The average value range of n is 5-12000.

2. A method for preparing the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative according to claim 1, characterized in that: Firstly, chitosan is used as a raw material to react with chloroacetic acid to obtain a carboxymethyl chitosan intermediate, and then sodium iodide is used as a catalyst to react with a nucleophilic agent methyl iodide under alkaline conditions to obtain a carboxymethyl chitosan quaternary ammonium salt, and finally an active guanidine salt is introduced into the carboxymethyl chitosan quaternary ammonium salt through an ion exchange reaction to obtain a guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative shown in formula 1.

3. The preparation method according to claim 2, characterized in that: (1) Preparation of carboxymethyl chitosan: chitosan was uniformly dispersed in isopropanol, and a 40% NaOH solution was slowly added dropwise, and stirred at 50-60°C for 1 h. Then, a chloroacetic acid aqueous solution was added to the system, and the reaction was stirred at 50-60°C for 4 h. After the reaction was completed, anhydrous ethanol was used for precipitation, and carboxymethyl chitosan was obtained after freeze-drying. (2) Preparation of carboxymethyl chitosan quaternary ammonium salt: carboxymethyl chitosan was uniformly dispersed in 1-methyl-2-pyrrolidone, sodium iodide, sodium hydroxide solution and methyl iodide were added in sequence under stirring at room temperature, refluxed at 60°C for 2 h, and then excess ethanol was added for precipitation. After washing and filtration, carboxymethyl chitosan quaternary ammonium salt was obtained; (3) Preparation of guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives: After dissolving the carboxymethyl chitosan quaternary ammonium salt obtained in the above step (2) in deionized water, different guanidine salts were added respectively and stirred at room temperature for 12 hours. After dialysis and freeze-drying, the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivatives were obtained.

4. The preparation method according to claim 3, characterized in that: The guanidine salt in step (3) is guanidine hydrochloride, aminoguanidine hydrochloride or 1,3-diaminoguanidine hydrochloride.

5. The preparation method according to claim 3, characterized in that: In step (1), the amount of isopropanol used is 10-12 mL per 1 g of chitosan, the amount of NaOH solution used is 3-4 mL per 1 g of chitosan, the molar ratio of chloroacetic acid to chitosan is (1-2):1, and the amount of anhydrous ethanol used is 150-200 mL per 1 g of chitosan; In step (2), the amount of 1-methyl-2-pyrrolidone used is 30-40 mL per 1 g of carboxymethyl chitosan, and the amount of sodium iodide, sodium hydroxide, and methyl iodide used is 1.5-2 g of sodium iodide, 20-30 mmol of sodium hydroxide, and 5-7 mL of methyl iodide per 1 g of carboxymethyl chitosan; The amount of deionized water used in step (3) is 20-30 mL per 1 g of carboxymethyl chitosan quaternary ammonium salt, and the molar ratio of the carboxymethyl chitosan quaternary ammonium salt to the guanidine salt is 1:

1.

6. The preparation method according to claim 3, characterized in that: In step (3), the solution is added to a dialysis bag with a molecular weight cutoff of 10,000, and the dialysis is stirred for 48 hours to remove the residual reagents of the reaction, thereby completing the dialysis.

7. An application of the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative according to claim 1, characterized in that: The invention discloses an application of the guanidine-containing carboxymethyl chitosan quaternary ammonium salt derivative in the preparation of antioxidants.

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