阅读说明：本技术 明胶胍基衍生物的制备方法和应用 (Preparation method and application of gelatin guanidino derivative ) 是由 董庆丰 李立 康永峰 张莹莹 赵美艳 于 2020-07-10 设计创作，主要内容包括：本发明提供了一种明胶胍基衍生物的制备方法和应用,其制备方法包括如下步骤：将明胶加入去离子水中,加热搅拌得到明胶溶液；在明胶溶液内加入胍基改性剂,反应冷却,将反应溶液透析,冷冻干燥,得到明胶胍基衍生物；本发明的明胶胍基衍生物在医药或食品中得以应用；将明胶胍基衍生物溶于水中,配制成明胶胍基衍生物溶液；然后将其通过静电纺丝机喷涂到食品表面,形成纤维薄膜；本发明的制备方法通过简单的加热和搅拌操作,将具有抑菌活性的胍基引入明胶分子中,使得明胶胍基衍生物具有良好的抑菌性能,从而拓宽了明胶的应用范围,进一步提升了明胶的使用价值。(The invention provides a preparation method and application of a gelatin guanidino derivative, wherein the preparation method comprises the following steps: adding gelatin into deionized water, heating and stirring to obtain gelatin solution; adding a guanidyl modifier into the gelatin solution, reacting and cooling, dialyzing the reaction solution, and freeze-drying to obtain a gelatin guanidyl derivative; the gelatin guanidino derivative is applied to medicines or foods; dissolving the gelatin guanidyl derivative in water to prepare a gelatin guanidyl derivative solution; then spraying the fiber film on the surface of the food through an electrostatic spinning machine to form a fiber film; according to the preparation method, guanidino with antibacterial activity is introduced into gelatin molecules through simple heating and stirring operations, so that the gelatin guanidino derivative has good antibacterial performance, the application range of gelatin is widened, and the use value of gelatin is further improved.)

1. A preparation method of a gelatin guanidyl derivative is characterized in that: which comprises the following steps:

(1) adding gelatin into deionized water, heating to 40-70 ℃, and stirring to obtain a gelatin solution;

(2) adding a guanidyl modifier into the gelatin solution, reacting for 6-24h, cooling to 40-50 ℃, dialyzing the reaction solution, and freeze-drying to obtain the gelatin guanidyl derivative.

2. The method of claim 1, wherein: in the step (1), the molecular weight of the gelatin is 10-30 ten thousand, and the gel strength of the gelatin is 200-300 Bloom.

3. The method of claim 1, wherein: in the step (1) and the step (2), the molar ratio of the primary amino group modifier to the guanidyl modifier in the gelatin is 1 (0.2-2).

4. The method of claim 1, wherein: in the step (2), the guanidyl modifier is selected from more than one of O-methylisourea sulfate, S-ethylisothiourea hydrobromide or dicyanodiamide.

5. A gelatin guanidino derivative characterized by: which is obtained by the production method according to any one of claims 1 to 4.

6. Use of the gelatin guanidino derivative of claim 5 in medicine or food.

7. Use according to claim 6, characterized in that: dissolving the gelatin guanidyl derivative in water to prepare a gelatin guanidyl derivative solution with the concentration of 5-20 wt%; then spraying the mixture on the surface of the food through an electrostatic spinning machine to form a fiber film.

8. Use according to claim 7, characterized in that: the temperature of the gelatin guanidino derivative solution is 38-42 ℃; the injection speed of the electrostatic spinning machine is 0.2-2mL/h, and the voltage is 12-18 kV; the spraying distance is 10-15 cm; the food rotation speed is 2-6r/min, and the ambient temperature is 25-35 deg.C.

Technical Field

The invention belongs to the technical field of functional polymer materials, and particularly relates to a preparation method and application of a gelatin guanidino derivative.

Background

Gelatin is fibrin obtained by moderate hydrolysis and heat treatment of animal collagen, and belongs to a natural polymer material. The gelatin has excellent film forming property, mechanical strength, surface activity and barrier property, and is low in price. Gelatin has been widely used in many fields such as medicine, food, paper, textile and packaging. Gelatin, which is a protein containing 18 kinds of amino acids, is a nutrient source for microorganisms and is easily deteriorated by contamination with microorganisms. At present, methods for improving the antibacterial property of gelatin mainly focus on blending modification, including chitosan, lysozyme, nisin, essential oil and the like. Under the condition of room temperature, gelatin is insoluble in common solvents such as water, ethanol, chloroform and the like, is dissolved in an acidic solution and is easy to hydrolyze, and a hot water solution of the gelatin is cooled to form gel, which brings certain difficulty to gelatin modification.

Arginine is the most basic amino acid, and the guanidyl on the side chain of arginine is the most basic organic base known at present, has stronger protonation capacity than primary ammonia in chitosan molecules, and has more excellent bacteriostatic effect. Guanidino can be introduced into a molecular structure, so that the material has better antibacterial activity, most typically polyhexamethylene guanidine which has broad-spectrum bactericidal effect and is widely applied to medicines, foods and daily life as an environment-friendly bactericidal disinfectant. However, no gelatin guanidino derivative is reported at present, and guanidino is introduced into gelatin, so that the antibacterial activity of the gelatin can be effectively improved, the service performance and the application range of the gelatin are expanded, and the gelatin guanidino derivative has important significance particularly in the fields of medicines and foods.

Disclosure of Invention

Aiming at the problems that gelatin is easily polluted by microorganisms, and has unstable performance and easy deterioration in the prior art, the guanidine salt derivative of gelatin is obtained by modifying gelatin with a guanidine modifier and is used for bacteriostasis and fresh keeping of food.

The invention aims to provide a preparation method of a gelatin guanidino derivative.

The second object of the present invention is to provide a gelatin guanidino derivative as described above.

The third purpose of the invention is to provide an application of the gelatin guanidino derivative.

In order to achieve the above primary object, the solution of the present invention is:

a preparation method of a gelatin guanidino derivative comprises the following steps:

(1) adding gelatin into deionized water, heating to 40-70 ℃, and stirring to obtain a gelatin solution;

(2) adding a guanidyl modifier into the gelatin solution, reacting for 6-24h, cooling to 40-50 ℃, dialyzing the reaction solution, and freeze-drying to obtain the gelatin guanidyl derivative.

Further, in the step (1), the molecular weight of the gelatin is 10-30 ten thousand, and the gel strength of the gelatin is 200-300 Bloom.

Further, in the step (1) and the step (2), the molar ratio of the primary amino group to the guanidyl modification reagent in the gelatin is 1: (0.2-2).

In step (2), the guanidyl modifier is selected from one or more of O-methylisourea sulfate, S-ethylisothiourea hydrobromide or dicyanodiamide.

In order to achieve the second objective, the solution of the invention is:

a gelatin guanidino derivative obtained by the preparation method.

In order to achieve the third object, the solution of the invention is:

the application of the gelatin guanidino derivative in medicines or foods.

Further, dissolving the gelatin guanidyl derivative in water to prepare a gelatin guanidyl derivative solution with the concentration of 5-20 wt%; then spraying the mixture on the surface of the food through an electrostatic spinning machine to form a fiber film.

Further, the temperature of the gelatin guanidyl derivative solution is 38-42 ℃; the injection speed of the electrostatic spinning machine is 0.2-2mL/h, and the voltage is 12-18 kV; the spraying distance is 10-15 cm; the food rotation speed is 2-6r/min, and the ambient temperature is 25-35 deg.C.

Due to the adoption of the scheme, the invention has the beneficial effects that:

according to the preparation method, guanidino with antibacterial activity is introduced into gelatin molecules through simple heating and stirring operations, so that the gelatin guanidino derivative has good antibacterial performance, the application range of gelatin is widened, and the use value of gelatin is further improved.

Drawings

FIG. 1 is a nuclear magnetic hydrogen spectrum of the gelatin guanidino derivative of the present invention.

Figure 2 is a schematic representation of a fibrous film after spraying of a gelatin guanidino derivative onto a fruit according to various embodiments of the present invention.

Fig. 3 is a schematic diagram of the bacteriostatic effect of the gelatin guanidino derivative in each embodiment of the invention.

Detailed Description

The invention provides a preparation method and application of a gelatin guanidino derivative.

< Process for producing gelatin guanidino derivative >

The preparation method of the gelatin guanidino derivative comprises the following steps:

(1) adding 1-15g of gelatin into 100mL of deionized water, heating to 40-70 ℃, and mechanically stirring to completely dissolve the gelatin to obtain a gelatin solution;

(2) adding a certain amount of guanidyl modifier into the gelatin solution, reacting for 6-24h, cooling to 40-50 ℃, adding the reaction solution into a dialysis bag with the molecular weight cutoff of 12-14 ten thousand, dialyzing with deionized water at 38-45 ℃ for 1-4 days, and freeze-drying to obtain the gelatin guanidyl derivative.

Wherein, in the step (1), the molecular weight of the gelatin is 10-30 ten thousand, and the gel strength of the gelatin is 200-300 Bloom.

In the step (1) and the step (2), the molar ratio of the primary amino group to the guanidyl modifier in the gelatin is 1 (0.2-2).

In the step (2), the guanidyl modifier is selected from more than one of O-methylisourea sulfate, S-ethylisothiourea hydrobromide or dicyanodiamine. The function of the guanidyl modifier is as follows: which grafts the guanidino group to the gelatin molecule by reaction with the amino group in the gelatin molecule, thereby obtaining a gelatin guanidino derivative.

< gelatin guanidino derivatives >

The gelatin guanidino derivative is obtained by the preparation method.

As shown in fig. 1, when the nuclear magnetohydrograms of gelatin and gelatin guanidino derivatives were compared, it was found that the nuclear magnetohydrogram of gelatin guanidino derivatives had a peak at 9.9ppm, which corresponds to the hydrogen at the N ═ H position in the guanidino group, indicating that gelatin guanidino derivatives had been successfully produced.

< use of gelatin guanidino derivatives >

The gelatin guanidyl derivative can be applied to medicines or foods and can be practically applied to the field of food preservation.

Specifically, dissolving gelatin guanidyl derivative in water to prepare a gelatin guanidyl derivative solution with the concentration of 5-20 wt%; then spraying the mixture on the surface of the food through an electrostatic spinning machine to form a fiber film.

Wherein, the temperature of the gelatin guanidino derivative solution can be 38-42 ℃, and is preferably 38 ℃; the injection speed of the electrostatic spinning machine can be 0.2-2mL/h, and is preferably 0.2 mL/h; the voltage may be 12-18kV, preferably 12 kV; the spraying distance can be 10-15cm, preferably 10 cm; the food can rotate at a speed of 2-6r/min, preferably 2 r/min; the ambient temperature may be 25-35 deg.C, preferably 25 deg.C.

The present invention will be further described with reference to the following examples.