CN102691214A - Antibacterial finishing method for grafting lysozyme to laccase-catalyzed hemp fibers (fabrics) - Google Patents

Abstract

The invention relates to an antibacterial finishing method for laccase-catalyzed hemp fiber (fabric) grafted with lysozyme, which belongs to the field of functional finishing of textiles. The purpose is to oxidize the lignin on the surface of the hemp fiber (fabric) by laccase to generate phenolic oxygen free radicals, and catalyze the grafting of lysozyme to the hemp fiber (fabric). The present invention can be treated by one-bath one-step method, one-bath two-step method or two-bath method. The one-bath one-step method is to put laccase, lysozyme and hemp fiber (fabric) into a solution with a certain pH value and temperature for a certain period of time; the one-bath two-step method is to first put laccase and hemp fiber (fabric) into React for a period of time in a solution with a certain pH value and temperature, and then add lysozyme for grafting; the two-bath method is to first put laccase and hemp fiber (fabric) into a solution with a certain pH value and temperature for a certain period of time, and then Put it into a certain pH value and temperature, and treat it in a solution containing lysozyme for a certain period of time. Through the present invention, the hemp fiber (fabric) can be endowed with excellent and broad-spectrum antibacterial properties.

Description

Antibacterial finishing method of laccase-catalyzed hemp fiber (fabric) grafted with lysozyme

technical field

The invention discloses an antibacterial finishing method for laccase-catalyzed hemp fiber (fabric) grafted with lysozyme, which belongs to the technical field of textile functional finishing.

Background technique

Antibacterial agents for hemp fiber or fabric antibacterial finishing mainly include inorganic, organic and natural antibacterial agents. Among these three types of antibacterial agents, organic antibacterial agents have poor heat resistance and are easy to decompose, while natural antibacterial agents have poor heat resistance and are difficult to process. At present, inorganic antibacterial agents with good heat resistance, wide antibacterial spectrum and long validity period are the most widely used.

Inorganic antibacterial agents are mostly metal ions and some photocatalytic antibacterial agents and composite antibacterial finishing agents. The composition of the inorganic antibacterial agent mainly includes a carrier and an antibacterial component. The carrier is not an antibacterial component, but ensures the stability of the active component and has slow-release properties. Antibacterial components are mainly some metal ions, such as Pd, Hg, Ag, Cu, Zn, etc. and their compounds, which can denature or inactivate bacteria by combining with cell proteins in bacteria. Considering safety, Ag, Cu, Zn are often used. However, due to the color of Cu ions, it affects the appearance of the fabric; Zn has poor antibacterial properties, and its strength is only 1/1000 of that of Ag. Therefore, the vast majority of commercial products on the market use silver-loaded inorganic antibacterial agents. There is no definite conclusion on the antibacterial mechanism of silver series. There are mainly contact antibacterial mechanism and photocatalytic antibacterial mechanism. Most people agree with the contact antibacterial mechanism. After contacting the bacteria, Ag is firmly adsorbed on the negatively charged cell membrane by Coulomb gravity, and further penetrates the cell wall into the inside of the bacteria, reacts with the sulfhydryl group in it, destroys the activity of cell synthetase, and causes the cells to lose their ability to divide and proliferate and die. Moreover, Ag will be freed from the dead bacteria to continue to sterilize, and the antibacterial effect is relatively long-lasting. The problems of silver series antibacterial agents are mainly that Ag+ is a strong oxidant, and it will react with sulfur in the air if it is left in the air for a long time, and the color changes from light brown to brown, dark brown, brown, black, etc., which greatly limits its application. ; In addition, Ag is the most effective against bacteria, but not very effective against fungi and molds. Inorganic antibacterial agents have good heat resistance, but it is difficult to obtain durable effects when used in textile finishing, and most varieties have heavy metal toxicity problems.

Most of the organic series are traditional antibacterial agents, with organic acids, phenols, and alcohols as the main components, and the antibacterial mechanism is to destroy cell membranes and block protein denaturation and metabolism. The advantages are strong bactericidal power, long-lasting effect, and rich sources; , will produce microbial resistance, poor heat resistance, easy migration, etc. A kind of organic antibacterial agent depends on the group that can bring into play toxicity on the one hand to the poisonous killing of microorganism and inhibitory performance of this antibacterial compound; ), the arrangement of each atom and group in the molecule, the spatial arrangement, and the molecular reactivity are closely related.

Organosilicon quaternary ammonium salt series antibacterial sanitation finishing agent is a new type of cationic surfactant, its molecular structure is highly variable, its performance is excellent, and its synthesis is simple. The most famous is Dow Corning’s DC-5700, whose active ingredient is 3-(trimethoxysilyl)propyldimethyloctadecyl chloride, which has the characteristics of durability, safety and broad-spectrum antibacterial , a commodity 3-(trimethoxysilyl)propyldimethyltetradecyl quaternary ammonium salt similar in structure to DC-5700, with similar properties. Organic antibacterial agents have good effects and many varieties, and are currently the most widely used antibacterial agents. However, due to limitations in antibacterial spectrum, heat and weather resistance, persistence, safety in use, and bacterial resistance Its application is limited in some occasions.

Natural antibacterial agents are the earliest antibacterial agents used by humans, including chitosan, hibiscus alcohol, turmeric root alcohol, and Mengzong bamboo extract. The main antibacterial mechanism is considered to be similar to organic quaternary ammonium salts. Currently the most commonly used is chitosan. Chitosan is the only natural alkaline polysaccharide that has been found in nature. It has good antibacterial properties, biocompatibility, adsorption properties, non-toxicity, and is easy to modify and modify, and is easy to process into fibers, films, particles, etc. Various forms, so that it can adapt to the needs of various environmental applications. Because chitosan has good antibacterial properties and broad antibacterial spectrum, it can endow fabrics with good antibacterial properties. However, natural antibacterial agents, such as some bactericidal plants and minerals, have a narrow application range, and most of them seriously affect the shade of fabrics.

There are many ways for antibacterial agents to inhibit or kill bacteria. Different types of antibacterial agents have different antibacterial mechanisms, which can be summarized as follows: (1) inactivate various metabolic enzymes in bacterial cells to kill bacteria; 2) chemically react with intracellular protease to destroy its function; (3) inhibit sporulation, block DNA synthesis, and inhibit cell growth; (4) speed up the phosphoric acid chloride reduction system and disrupt the normal growth system of cells; ( 5) destroy the energy release system in the cell; (6) hinder the electron transfer system and the process of amino acid transesterification; (7) destroy the cell wall and kill bacteria through the adsorption of the electrostatic field.

At present, the requirements for antibacterial textiles are mainly high-efficiency and broad-spectrum antibacterial ability; long-lasting antibacterial effect, washing resistance, wear resistance, and long life; heat resistance, sunlight resistance, not easy to decompose and fail, soft, moisture-permeable, and good comfort; use Safe, harmless to health, and will not pollute the environment. The ideal characteristics of antibacterial finishing agents are: (1) It has excellent functions of inhibition, sterilization, disinfection and deodorization, and has a broad-spectrum antibacterial effect. (2) The antibacterial effect is durable and resistant to rinsing and sunlight. (3) It has no side effects on the human body, is non-toxic, and does not pollute the environment. (4) It does not affect the style characteristics of the textile itself, does not damage the fibers, and does not affect the efficacy of other textile auxiliaries. (5) The antibacterial finishing agent is easy to use, low in cost, and compatible with other finishing agents.

Lysozyme, also known as cell mureinase or N-acetyl murein hydrolase, is a new type of biological antibacterial agent, which has the advantages of strong antibacterial, safe and non-toxic, good thermal stability and wide range of action. In 1922, British bacteriologist A. Fleming discovered that human saliva and tears contained enzymes that dissolve bacterial cell walls. Because of their bacteriolytic effect, they were named lysozyme. Since then, lysozyme has also been found in various tissues and secretions of humans and animals, as well as some plants and microorganisms. With the deepening of research, it is found that not only lysozyme that dissolves bacterial cell walls, but also types that act on fungal cell walls.

The cell wall of bacteria is composed of murein, which is a polymer composed of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) alternately. The residues of muramic acid can be connected with polypeptides, called for peptidoglycan. Peptidoglycan is the main component of the bacterial cell wall. It is composed of NAM, NAG and peptide "tail" (generally 4 amino acids). The D-lactyl carboxyl group is connected to the third carbon atom of NAM, and the peptide tails are connected by a peptide "bridge" (peptide bond or a few amino acids). NAM, NAG, peptide "tail" and peptide "bridge" are common The multi-layer network structure of peptidoglycan is used as the skeleton of the cell wall. Any chemical bond breakage in the above structure can cause damage to the bacterial cell wall. Lysozyme can effectively hydrolyze the peptidoglycan of the bacterial cell wall, and its hydrolysis site is the β- 1, 4 glycosidic bonds, the result is that the bacterial cell wall becomes loose, loses the protective effect on the cell, and finally the cell lyses and dies.

Based on the antibacterial properties of lysozyme, immobilizing it on the surface of textiles is expected to establish a new antibacterial method for textiles.

At present, lysozyme is generally through the cross-linking of chemical cross-linking agents, such as glutaraldehyde, the aldehyde group at one end of the molecule reacts with the hydroxyl group on the hemp fiber, and the aldehyde group at the other end reacts with the amino group on the enzyme molecule. Chemical cross-linking of enzyme molecules. However, the chemical cross-linking method will leave harmful chemical cross-linking agents on the hemp fabric, which will affect the health of consumers, and the chemical cross-linking agents will also affect the enzyme activity of lysozyme.

Lysozyme can also be adsorbed on linen fabric by adsorption method. However, the lysozyme adsorbed on the hemp fabric by the adsorption method has poor binding force with the hemp, and its antibacterial effect is not durable, and it is not resistant to washing.

The surface of hemp fiber is rich in lignin (specific content is: flax 18.6%-20.6%, jute 13.6%-20.4%, ramie 13.1%-16.7%, hemp 17.9%-22.4%, sisal 10%-14.2%). Lignin is a complex phenolic compound formed by four alcohol monomers (p-coumaryl alcohol, coniferyl alcohol, 5-hydroxy coniferyl alcohol and sinapyl alcohol), and there are three types of guaiacyl, syringyl and hydroxyphenyl basic structure. Studies at home and abroad have shown that lignin is a suitable substrate for laccase, and the phenolic hydroxyl groups in its molecular structure can be oxidized by laccase to form phenolic oxygen free radicals. These highly reactive active particles can trigger Exogenous molecules such as compounds containing amino groups are grafted and polymerized to prepare novel functional materials.

The present invention utilizes the characteristics that hemp fiber is rich in lignin and laccase can catalyze the oxidation of phenolic hydroxyl groups on lignin to form phenolic oxygen free radicals, triggering the "graft polymerization" of lysozyme containing amino groups to the surface of hemp fiber containing lignin, thereby Endow hemp fiber with excellent and long-lasting antibacterial properties.

Contents of the invention

In the present invention, hemp fibers such as ramie, flax, jute, and hemp rich in lignin are used as representative fibers, and the lignin on the surface of the hemp fiber (fabric) is oxidized by laccase to generate phenolic oxygen free radicals, and the generated phenolic oxygen free radicals Catalyze the grafting of lysozyme to the lignin on the surface of the hemp fiber (fabric), endow the hemp fiber (fabric) with excellent and long-lasting antibacterial properties.

Technical scheme of the present invention:

A kind of antibacterial finishing method of laccase-catalyzed hemp fiber (fabric) grafted with lysozyme, both can adopt one-bath one-step method or one-bath two-step method to process, also can adopt two-bath method to process, trigger hemp fiber (fabric) by laccase ) surface lignin oxidation to generate phenolic oxygen free radicals, the generated phenolic oxygen free radicals catalyze the grafting of lysozyme to the lignin on the surface of the hemp fiber (fabric), endowing the hemp fiber (fabric) with excellent and lasting antibacterial properties.

One-bath one-step treatment is to put laccase, lysozyme and hemp fiber (fabric) into a buffer solution with a certain pH value at the same time, and treat it at a certain temperature for a certain period of time. When the phenolic hydroxyl value on the surface generates phenolic oxygen free radicals, lysozyme is grafted onto lignin, then washed with water and dried at low temperature; the one-bath two-step process is to first put laccase and hemp fiber (fabric) into a certain pH In the buffer solution of value, react for a period of time at a certain temperature and then add lysozyme to carry out grafting reaction after reacting for a period of time, then wash with water, dry at low temperature; ) into a buffer solution of a certain pH value, treated at a certain temperature for a certain period of time, then taken out and washed fully, and then the hemp fiber (fabric) pretreated with laccase is put into a buffer solution containing lysozyme at a certain pH value Treat it at a certain temperature for a certain period of time, then fully wash with water and dry at low temperature.

Process flow of the present invention is:

One-bath one-step treatment: put 1%-50% laccase (for fiber or fabric weight, the same below), 2%-70% lysozyme and hemp fiber (fabric) into acetic acid with a pH value of 4.0-7.0 at the same time - In sodium acetate buffer solution, bath ratio 1:10-100, at 30°C-65°C for 0.5h-20h, laccase catalyzed oxidation of phenolic hydroxyl value on lignin in hemp fiber (fabric) to generate phenolic oxygen free radical At the same time, phenolic oxygen free radicals grafted lysozyme onto lignin, and then washed with water and dried below 60°C.

One-bath two-step treatment: first put 1%-50% laccase and hemp fiber (fabric) into acetic acid-sodium acetate buffer solution with a pH value of 4.0-7.0, bath ratio 1:10-100, at 30°C React at -65°C for 0.5h-20h, first generate phenolic oxygen radicals on fibers or fabrics, then add 2%-70% lysozyme, treat at 30°C-65°C for 0.5h-20h, and carry out grafting reaction , then washed with water, and dried at a low temperature below 60°C.

Two-bath treatment: first put 1%-50% laccase and hemp fiber (fabric) into the acetic acid-sodium acetate buffer solution with a bath ratio of 1:10-100 and a pH value of 4.0-7.0, at 30°C-65°C Treat for 0.5h-20h to make the phenolic hydroxyl groups in the lignin on the hemp fiber or fabric generate phenolic oxygen free radicals, then take it out and wash it fully. Then put the hemp fiber (fabric) pretreated by laccase into the acetic acid-sodium acetate buffer solution with a pH value of 4.0-7.0 and containing 2%-70% lysozyme, and treat it at 30°C-65°C for 0.5h- 20h, then fully washed with water, and dried at a low temperature below 60°C.

A laccase-catalyzed antibacterial finishing method of hemp fiber (fabric) grafted with lysozyme is characterized in that the used hemp fiber is a fiber rich in lignin, such as flax fiber, hemp fiber, ramie fiber, sisal fiber, jute fiber The fiber can also be other fibers rich in lignin such as bamboo fiber, straw fiber, wood fiber and the like.

A laccase-catalyzed antibacterial finishing method of hemp fiber (fabric) grafted with lysozyme is characterized in that the used hemp fiber can be the hemp fiber itself, or a woven fabric, knitted fabric or fabric made of these hemp fibers. non-woven fabric.

Beneficial effects of the present invention:

The present invention triggers the oxidation of lignin on the surface of the hemp fiber (fabric) by laccase to generate phenolic oxygen free radicals, and the generated phenolic oxygen free radicals catalyze the grafting of lysozyme to the lignin on the surface of the hemp fiber (fabric), endowing the hemp fiber (fabric) Fabric) excellent, long-lasting, broad-spectrum antibacterial properties. Since the lysozyme used is a biological antibacterial agent, it has the characteristics of high safety and no toxic and side effects on human body. In addition, because the biocatalytic grafting method is used to graft lysozyme onto the hemp fiber (fabric), the antibacterial effect is durable and can withstand multiple washings, and it avoids the chemical cross-linking method to damage the fiber and to lyse the bacteria. The impact of enzyme activity and the residue of chemical cross-linking agents on the fabric may cause potential harm to the human body and other disadvantages.

Detailed ways

Example 1

Linen fabric with antibacterial finish in a one-bath, one-step process.

Put 15g laccase, 20g lysozyme and 1000g desized, scorched and bleached linen fabric into 50L acetic acid-sodium acetate buffer solution with pH value 5.0 at the same time, bath ratio 1:50, and treat at 50°C for 5h, Wash with water and dry at 60°C.

The antibacterial properties of the linen fabrics treated above are shown in Table 1.

Table 1 Antibacterial effect of laccase on linen fabric grafted with lysozyme

It can be seen from Table 1 that the bacteriostatic rate of the linen fabric grafted with lysozyme reached 60.38%. After fully washed with water, its antibacterial rate dropped slightly to 56.15%. Therefore, the linen fabric with laccase grafted with lysozyme has a high antibacterial rate and a long-lasting antibacterial effect.

Example 2

Jute fabric with antimicrobial finish using the two-bath method.

Put 20 g of laccase and 1000 g of jute fabric into 60 L of acetic acid-sodium acetate buffer solution with a pH value of 5.0, bath ratio 1:60, and treat at 48°C for 4 hours to make the phenolic hydroxyl groups in the lignin on the jute fabric generate phenolic oxygen free Base, then remove and rinse thoroughly with water. Then put the jute fabric pretreated by laccase into 40 L of acetic acid-sodium acetate buffer solution containing 25 g of lysozyme at a bath ratio of 1:40 and a pH value of 5.5, and treat it at 52° C. for 8 hours, then fully wash it with water, and dry it at 55° C. Dry.

Through the jute fabric of above-mentioned treatment, its antibacterial performance is as shown in table 2.

Table 2 Antibacterial effect of jute fabric laccase grafted with lysozyme

It can be seen from Table 2 that the bacteriostatic rate of the jute fabric grafted with laccase and lysozyme was 72.87%. After fully washed with water, its antibacterial rate dropped slightly to 65.59%.

Claims (4)

1. a laccase catalyzed antibacterial finishing method of hemp fiber (fabric) grafted lysozyme, characterized in that the lignin oxidation on the surface of hemp fiber (fabric) is triggered by laccase to generate phenolic oxygen free radicals, and the generated phenolic oxygen free radicals The base catalyzes the grafting of lysozyme to the lignin on the surface of the hemp fiber (fabric), endowing the hemp fiber (fabric) with antibacterial properties. 2. the antibacterial finishing method of a kind of laccase catalyzed hemp fiber (fabric) grafted lysozyme according to claim 1, it is characterized in that the method both can adopt one-bath one-step method or one-bath two-step method to process, also can Treated by two-bath method; One-bath one-step treatment is to put 1%-50% laccase (for fiber or fabric weight, the same below), 2%-70% lysozyme and hemp fiber (fabric) into acetic acid with a pH value of 4.0-7.0 at the same time - In sodium acetate buffer solution, bath ratio 1:10-100, at 30°C-65°C for 0.5h-20h, laccase catalyzed oxidation of phenolic hydroxyl value on lignin in hemp fiber (fabric) to generate phenolic oxygen free radical At the same time, phenolic oxygen free radicals grafted lysozyme onto lignin, then washed with water, and dried below 60°C; One-bath two-step treatment is to put 1%-50% laccase and hemp fiber (fabric) into the acetic acid-sodium acetate buffer solution with pH value 4.0-7.0, bath ratio 1:10-100, at 30 ℃ React at -65°C for 0.5h-20h, first generate phenolic oxygen radicals on fibers or fabrics, then add 2%-70% lysozyme, treat at 30°C-65°C for 0.5h-20h, and carry out grafting reaction , then washed with water, and dried at a low temperature below 60°C; The two-bath method is to first put 1%-50% laccase and hemp fiber (fabric) into the acetic acid-sodium acetate buffer solution with a bath ratio of 1:10-100 and a pH value of 4.0-7.0 at 30°C-65°C. Treat for 0.5h-20h to make the phenolic hydroxyl groups in the lignin on the hemp fiber or fabric generate phenolic oxygen free radicals, then take out and wash fully; then put the hemp fiber (fabric) pretreated with laccase into a pH value of 4.0-7.0 1. Treat in acetic acid-sodium acetate buffer solution containing 2%-70% lysozyme at 30°C-65°C for 0.5h-20h, then fully wash with water, and dry at low temperature below 60°C. 3. the antibacterial finishing method of a kind of laccase catalyzed hemp fiber (fabric) grafted lysozyme according to claim 1, it is characterized in that used hemp fiber is the fiber that is rich in lignin, as flax fiber, hemp fiber , ramie fiber, sisal fiber, jute fiber, and other fibers rich in lignin such as bamboo fiber, straw fiber, wood fiber, etc. 4. the antibacterial finishing method of a kind of laccase catalyzed hemp fiber (fabric) grafted lysozyme according to claim 1, it is characterized in that used hemp fiber can be hemp fiber itself, also can be made of these hemp fibers Made of woven, knitted or nonwoven fabrics.