阅读说明：本技术 一种双赖氨酸/枸杞多糖协同抗菌剂及制备方法及应用 (dilysine/lycium barbarum polysaccharide synergistic antibacterial agent, and preparation method and application thereof ) 是由 林琳 周昌倩 崔海英 戴锦铭 于 2019-08-30 设计创作，主要内容包括：本发明属于食品安全领域,具体涉及一种双赖氨酸/枸杞多糖抗菌剂及制备方法及应用。本发明利用枸杞多糖多种有益于人体的生理活性和抑菌特性,结合双赖氨酸与多糖之间静电复合作用,增加多糖溶液的稳定性,制备一种安全绿色、无毒副作用的新型抗菌剂。该种新型抗菌剂能有效抑制各种细菌如大肠杆菌(E.coli),金黄色葡萄球菌(S.aureus)和耐甲氧西林金黄色葡萄球菌(MRSA)的生长,与单独的双赖氨酸和枸杞多糖相比抗菌效果有了明显的提高。(The invention belongs to the field of food safety, and particularly relates to a dilysine/lycium barbarum polysaccharide antibacterial agent, and a preparation method and application thereof. The invention utilizes various physiological activities and antibacterial properties of the lycium barbarum polysaccharide beneficial to human bodies, combines the electrostatic composite effect between the dilysine and the polysaccharide, increases the stability of the polysaccharide solution, and prepares the novel antibacterial agent which is safe, green and free of toxic and side effects. The novel antibacterial agent can effectively inhibit the growth of various bacteria such as Escherichia coli (E.coli), Staphylococcus aureus (S.aureus) and methicillin-resistant Staphylococcus aureus (MRSA), and has an obviously improved antibacterial effect compared with single dilysine and lycium barbarum polysaccharide.)

1. The dilysine/lycium barbarum polysaccharide synergistic antibacterial agent is characterized by being prepared by the following method: firstly, dissolving lycium barbarum polysaccharide dry powder, preparing a mother solution, diluting into lycium barbarum polysaccharide application solutions with different concentrations, adding solid dilysine dry powder, performing magnetic stirring, performing ultrasonic treatment to obtain uniformly dispersed dilysine/lycium barbarum polysaccharide synergistic antibacterial agent, and filtering and sterilizing the obtained antibacterial agent solution through a filter membrane for later use.

2. The dilysine/lycium barbarum polysaccharide synergistic antibacterial agent as claimed in claim 1, wherein the magnetic stirring time is 1h, the ultrasonic power is 300W, and the ultrasonic treatment is 15 min.

3. The dilysine/lycium barbarum polysaccharide synergistic antimicrobial agent of claim 1, wherein the filter membrane has a pore size of 0.22 μm and is stored at 4 ℃ or-20 ℃ until use.

4. The dilysine/lycium barbarum polysaccharide synergistic antimicrobial agent of claim 1, wherein the lycium barbarum polysaccharide mother liquor is prepared by the method comprising: dissolving the lycium barbarum polysaccharide dry powder in sterile deionized water to prepare 1.0mg/mL mother liquor, and diluting the mother liquor into polysaccharide application solutions with different concentrations before use.

5. The dilysine/lycium barbarum polysaccharide synergistic antibacterial agent according to claim 1, wherein the concentration of solid dilysine dry powder contained in the obtained uniformly dispersed dilysine/lycium barbarum polysaccharide synergistic antibacterial agent is 3.3-8.3mg/mL, and the final addition concentration of lycium barbarum polysaccharide powder in the synergistic antibacterial agent is 0.4-1.0 mg/mL.

6. The use of the dilysine/lycium barbarum polysaccharide synergistic antimicrobial agent as claimed in any one of claims 1-5, as an antimicrobial agent in the field of food preservation.

Technical Field

The invention belongs to the field of food safety, and relates to a synergistic antibacterial agent, in particular to a safe, nontoxic, stable and efficient synergistic antibacterial agent prepared by utilizing the antibacterial action of lycium barbarum polysaccharide and the electrostatic interaction of dilysine on the polysaccharide.

Background

With the improvement of the consumption level and living level of people, people pay more and more attention to the aspects of self health, health care and the like, and particularly in the aspect of food production and processing, the people tend to change the directions of green and natural. Preservatives are one of the important additives in the food industry, and are most commonly chemically synthesized in the food industry in the world nowadays, and the problems of possible cancers, deformities and easy chronic poisoning of food caused by the preservatives have attracted extensive attention in various social circles. Therefore, it is becoming more and more important to accelerate the development of natural, safe, functional food preservatives. Since people are paying attention to the safety of food additives, they are keen on the expectations of natural food additives, and the development of natural, safe and multifunctional food additives is a development direction of food industry. Dilysine, also known as Lysyllysine (L-lysylysine, L-Lys-L-Lys, KK), is a dipeptide consisting of two lysine residues, belonging to short cationic dipeptides. Compared with long-chain peptide, the cationic short peptide has the advantages of simple preparation, higher yield and low cost, is favorable for batch synthesis, and is an ideal antibacterial preparation because most of the antibacterial peptide is cationic peptide. Some dipeptides are known to have physiological or cell signal transduction effects, and a dilysine signal plays an important role in positioning a Golgi apparatus or an endoplasmic reticulum in a functional protein transport process, so that at present, researches on the physiological metabolism direction of the dilysine are only gathered at home and abroad, and the research on the bacteriostatic action of the dilysine is less. Because the amino acid is composed of amino acid, the amino acid is safe and nontoxic, and thus the amino acid has wide development and utilization prospects.

The medlar is one of rare Chinese herbal medicines with homology of medicine and food in China, has various health care effects, and is widely used for research and development of functional foods. Lycium Barbarum Polysaccharide (LBP) is the main functional component of Lycium barbarum, contains rhamnose, mannose, glucose, galactose and other saccharides, is an acidic polypeptide heteropolysaccharide protein complex, and has physiological effects of reducing blood sugar, reducing blood lipid, resisting oxidation, resisting tumor, resisting fatigue, regulating immunity, etc. In recent years, human medical research has achieved certain results in the aspect of the biological activity of lycium barbarum polysaccharide, and the research breadth and depth are also deepened continuously. According to the report, various plant polysaccharides have bacteriostatic effects, and the lycium barbarum polysaccharides have certain inhibitory effects on several common intestinal pathogenic bacteria and mold, and the bacteriostatic effect is more obvious along with the increase of the concentration. In addition, in the food containing the medlar, the content of medlar polysaccharide is increased, so that the breeding of intestinal pathogenic bacteria can be effectively prevented. The lycium barbarum polysaccharide can be used as a food additive or made into a fruit and vegetable coating preservative in the food industry to inhibit the growth of common microorganisms in food. Chinese wolfberry has high yield, good quality, high wolfberry polysaccharide content and simple extraction process, and the research and development of wolfberry polysaccharide can improve the added value of the product and has good market value.

Most polysaccharides and proteins in food are often associated with abundant conformational transitions and gelling behavior during processing and storage, and the effect of polysaccharide/protein electrostatic complexation on polysaccharide conformational transition is closely related to the molecular weight of the protein. When the molecular weight of the protein (polypeptide) is less than 1000Da, electrostatic recombination has a stabilizing effect on the helical structure of the polysaccharide, and the conclusion opens up a new technical way for regulating and controlling the gel behavior and the gel property of the charged polysaccharide. Therefore, on the basis of combining the antibacterial activity of the lycium barbarum polysaccharide, the dilysine dipeptide is introduced, so that the stability of the polysaccharide structure is enhanced, and a more stable, efficient and natural antibacterial agent is prepared.

There are many domestic patent applications for lycium barbarum polysaccharides. Chinese patent CN108619273A discloses a preparation method of plant fruit stone oral liquid for treating helicobacter pylori; chinese patent CN105797219A discloses a biological patch and a preparation method thereof; chinese patent CN109876154A discloses preparation of a lycium barbarum polysaccharide modified nanoparticle and research on anti-tumor activity of the lycium barbarum polysaccharide modified nanoparticle; chinese patent CN109805147A discloses a lycium ruthenicum polysaccharide chewable tablet and a preparation process thereof, but no patent about dilysine exists.

The antibacterial agent with excellent antibacterial effect is prepared by combining the dilysine and the lycium barbarum polysaccharide, and has good application prospect and market value.

Disclosure of Invention

The invention aims to provide an antibacterial agent with the synergistic effect of dilysine and lycium barbarum polysaccharide, a preparation method and application thereof in the field of life safety.

The preparation method of the synergistic antibacterial agent comprises the following steps: firstly, dissolving lycium barbarum polysaccharide dry powder, preparing a mother solution, diluting into lycium barbarum polysaccharide application solutions with different concentrations, adding solid dilysine dry powder, magnetically stirring for 1h, performing ultrasonic treatment at 30% ultrasonic power of 300W for 15min to obtain uniformly dispersed dilysine/lycium barbarum polysaccharide synergistic antibacterial agent, filtering and sterilizing the obtained antibacterial agent solution through a 0.22 mu m pore filter membrane, and storing at 4 ℃ or-20 ℃ for later use.

The preparation method of the wolfberry polysaccharide mother liquor comprises the following steps: dissolving the lycium barbarum polysaccharide dry powder in sterile deionized water to prepare 1.0mg/mL mother liquor, and diluting the mother liquor into polysaccharide application solutions with different concentrations before use.

The concentration of solid dilysine dry powder contained in the obtained uniformly dispersed dilysine/lycium barbarum polysaccharide synergistic antibacterial agent is 3.3-8.3mg/mL, and the final adding concentration of lycium barbarum polysaccharide powder in the synergistic antibacterial agent is 0.4-1.0 mg/mL.

Compared with the prior art, the invention has the following advantages:

1. The idea is novel, and the method has wide development and application prospects in the field of food preservation: the invention provides an implementation method for performing synergistic antibacterial on dilysine and lycium barbarum polysaccharide for the first time, and introduces dilysine dipeptide on the basis of combining the antibacterial activity of the lycium barbarum polysaccharide, so that the stability of the polysaccharide structure is enhanced, and a more stable, efficient and natural antibacterial agent is prepared.

2. The method is simple, low in cost and strong in practicability: the used materials of the dilysine/lycium barbarum polysaccharide synergistic antibacterial agent are easy to obtain, the preparation and operation methods are simple, the requirements on production processes and facilities are low, the practicability is high, and the requirements on large-scale production can be met.

3. The dilysine/lycium barbarum polysaccharide synergistic antibacterial agent prepared by the invention has good antibacterial activity to gram-positive bacteria and gram-negative bacteria, and especially has good antibacterial performance to staphylococcus aureus.

Drawings

FIG. 1 shows the antibacterial effect of dilysine and lycium barbarum polysaccharides on E.coli.

FIG. 2 shows the antibacterial effect of dilysine and lycium barbarum polysaccharides on Staphylococcus aureus.

FIG. 3 shows the antibacterial effect of dilysine and lycium barbarum polysaccharides on methicillin-resistant Staphylococcus aureus.

Detailed Description

The following examples illustrate specific embodiments of the present invention, but the scope of the present invention is not limited thereto.