Chinese herbal medicine-based environment-friendly antibacterial tussah silk gland protein fiber, fabric and preparation method thereof

Abstract

According to the environment-friendly antibacterial tussah silk gland protein fiber and fabric based on the Chinese herbal medicines, tussah silk gland protein serves as a source, five-year-old tussah is directly dissected, the tussah silk gland protein is obtained, and the Chinese herbal medicines with the antibacterial function such as coptis chinensis, dandelion, wormwood, honeysuckle and radix isatidis are introduced into the tussah silk gland protein, so that the antibacterial function of the tussah silk gland protein fiber is achieved. The antibacterial health-care tussah silk gland protein fiber containing Chinese herbal medicine effective components is prepared by adopting a microfluidic spinning technology, and has the characteristics of high Chinese herbal medicine content, strong durability and the like; according to the method, a cross-linking agent does not need to be used, complex processes such as tussah silk high-temperature degumming, bleaching and multifunctional after-finishing in the traditional antibacterial tussah silk preparation process are abandoned, the tussah silk gland protein obtaining process is green and environmentally friendly, no wastewater is discharged in the preparation process, the process is simple and easy to control, and the obtained tussah silk gland protein fiber is good in antibacterial effect and good in antibacterial property. The method can be widely applied to the fields of textiles, garments, medical materials and the like, and has a large-scale production prospect.

Description

Technical Field

[0001] The invention relates to the technical field of silk fibers and fabrics, and in particular to an environmentally friendly and antibacterial tussah silk gland protein fiber, a fabric and a preparation method thereof. Background Art

[0002] As a high-grade natural protein fiber, tussah silk has a long history of clothing and has excellent characteristics such as unique jewelry luster, natural luxury, smoothness and comfort. However, before practical application, tussah silk needs to go through complex processes such as degumming, smelting, washing, and finishing. This process will produce wastewater containing sericin, inorganic salts, dyes, dyeing auxiliaries, etc., which pollutes the environment and seriously restricts the development of the tussah silk industry. In addition, with the improvement of people's living standards, higher requirements are put forward for the antibacterial properties of tussah silk fibers, both in daily life and in the medical field.

[0003] Tussah silk fibers have poor antibacterial properties, and are often treated with antibacterial agents such as silver or nano-silver by coating or soaking them for functional finishing. This technology has serious impacts on the human body and the environment.

[0004] In order to improve the antibacterial properties of silk fibers and fabrics, the invention patent No. 202210434131.5 discloses an antibacterial silk fabric and its preparation method, and the fabric used is silk fabric. The silk is pre-treated with hydrogen peroxide, and after the pre-treatment, the silk fabric needs to be placed in an antibacterial finishing liquid containing 4-hydroxybenzophenone and formaldehyde aqueous solution. The prepared antibacterial silk fabric has an initial antibacterial rate of more than 97.0% for Escherichia coli and Staphylococcus aureus, and after 10 washes, the antibacterial rate can still reach more than 91.5%. The silk fiber is oxidized, and the composite antibacterial finishing liquid is an organic matter, which has a negative impact on the natural properties of silk, and the organic matter pollutes the environment and increases production costs.

[0005] The invention patent application with application number 202410156433.X discloses a new type of antibacterial silk and preparation method, and the fabric used is silk fabric. The silk is subjected to two antibacterial finishing. The first antibacterial finishing is to put the silk fabric into a composite finishing liquid containing porous barium sulfate microspheres, nano copper oxide, polyethylene glycol, and dodecyl peroxide for 5 to 50 minutes, and the silk after the first antibacterial finishing is alcoholized. After alcoholization, the silk is directly placed in the antibacterial finishing liquid of modified chitosan for 0.5 to 5 hours at a temperature of 10 to 20°C. The antibacterial rate of antibacterial silk fiber against Staphylococcus aureus and Escherichia coli is greater than 92% after washing 50 times. The antibacterial fiber finishing process is complicated, which leads to increased production costs and will have a certain impact on the structure and other properties of silk fabrics. Summary of the invention

[0006] In view of this, the present invention provides an environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine, fabric and its preparation method, which solves the problem that the current antibacterial silk fiber finishing process is complicated, resulting in increased production costs and affecting the structure and performance of silk fabrics.

[0007] To achieve the above-mentioned object of the invention, the method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber is characterized by comprising:

[0008] Extracting tussah silk gland protein;

[0009] Adding Chinese herbal medicine to the composite solution of tussah silk gland protein and sodium alginate to obtain a spinning solution;

[0010] The spinning solution is spun by a microfluidic spinning method to obtain environmentally friendly antibacterial tussah silk gland protein fibers.

[0011] In the present disclosure and possible embodiments, the Chinese herbal medicine is a mixture of one or more of coptis chinensis, dandelion, wormwood, honeysuckle, and isatis root, and the mass ratio of the Chinese herbal medicine to the tussah silk gland protein is 1:3 to 1:1.

[0012] In the present disclosure and possible embodiments, the method for extracting tussah silk gland protein comprises:

[0013] The fifth-instar tussah silkworm is dissected alive to obtain the tussah silk glands, the cleaned tussah silk glands are dissolved with a dissolving solution, and the insoluble matter therein is removed to obtain the tussah silk gland protein.

[0014] In the present disclosure and possible embodiments, the dissolving solution is a complex solution of Tris·HCl with a pH of 8 to 10 and an SDS solution with a concentration of 1 to 5%, and the volume ratio of the Tris·HCl to the SDS solution is 9:1 to 5:5;

[0015] The dissolution time is 1 to 3 hours, and the dissolution temperature is 30 to 40°C;

[0016] The mass ratio of the tussah silk gland to the dissolving solution is 1:1 。

[0017] In the present disclosure and possible embodiments, the environment temperature for dissecting the live fifth-instar tussah silkworm is 20-25° C., and the number of times the tussah silk gland is cleaned with distilled water is 3-6 times;

[0018] The insoluble matter is removed by centrifugation, the centrifugal speed is 6000-8000 rpm, the centrifugal time is 3-5 minutes, and the centrifugal temperature is -5-0°C.

[0019] In the present disclosure and possible embodiments, the composite volume ratio of the tussah silk gland protein to the sodium alginate solution with a mass concentration of 4% is 9:1 to 5:5.

[0020] In the present disclosure and possible embodiments, the microfluidic spinning method comprises:

[0021] The spinning solution is injected into a spinning chip, wherein the core layer is the spinning solution and the skin layer is the curing agent;

[0022] The core layer injection speed is 0.5-1 mL / h, and the skin layer injection speed is 3-8 mL / h.

[0023] In the present disclosure and possible embodiments, the curing agent is a CaCl2 solution with a mass concentration of 2 to 5%, a citric acid solution with a mass concentration of 5 to 10%, or a CaCl2 / citric acid composite curing agent, wherein the composite curing agent is a mixture of a CaCl2 solution with a mass concentration of 2 to 5% and a citric acid solution with a mass concentration of 5 to 10% in a volume ratio of 9:1 to 1:9; and / or,

[0024] The spinning chip is a skin-core structure, a single needle syringe or a multi-layer structure.

[0025] In a second aspect, the environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine is prepared by any method described in the first aspect.

[0026] In a third aspect, the fabric is woven using the environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine as described in the second aspect.

[0027] The present invention has the following beneficial effects:

[0028] The environmentally friendly antibacterial tussah silk gland protein fiber of the present invention uses tussah silk gland protein as the source, directly dissects five-star tussah silkworms to obtain tussah silk gland protein, and introduces Chinese herbal medicines with antibacterial function such as coptis chinensis, dandelion, wormwood, honeysuckle, and isatis root into it, and adopts microfluidic spinning technology to prepare antibacterial and health-care tussah silk gland protein fiber containing effective ingredients of Chinese herbal medicines, which has the characteristics of high content of Chinese herbal medicines and strong durability. The method does not require the use of a cross-linking agent, and abandons the complex processes of high-temperature degumming, bleaching, and multifunctional finishing of tussah silk in the preparation process of traditional antibacterial tussah silk. The process for obtaining tussah silk gland protein is green and environmentally friendly, there is no wastewater discharge in the preparation process, and the process is simple and easy to control. The obtained tussah silk gland protein fiber has good antibacterial effect and can be widely used in the fields of textiles and clothing, medical materials, etc., and has great prospects for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0030] Figure 1 is the inhibition zone of the fiber of Example 1 of the present disclosure against Staphylococcus aureus;

[0031] Figure 2 This is the inhibition zone of the fiber of Example 1 of the present disclosure against Escherichia coli. DETAILED DESCRIPTION

[0032] The present disclosure is described below based on embodiments, but it is worth noting that the present disclosure is not limited to these embodiments. In the detailed description of the present disclosure below, some specific details are described in detail. However, for the parts that are not described in detail, those skilled in the art can also fully understand the present disclosure.

[0033] The preparation method of the environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine provided in each embodiment of the present disclosure comprises the following specific steps:

[0034] Step S1, extracting tussah silk gland protein:

[0035] A live fifth-instar tussah silkworm was selected and directly dissected at a certain temperature to obtain the tussah silk gland, which was then washed with distilled water. A certain amount of the tussah silk gland was then weighed and placed in a dissolving solution to dissolve. After the dissolution was completed, the insoluble matter was removed by low-temperature high-speed centrifugation to obtain the tussah silk gland protein solution.

[0036] In a specific embodiment, the certain temperature used is 20-25° C., and the number of distilled water washing times is 3-6 times.

[0037] In a specific embodiment, the amount used is 4-8 g, and the amount of the dissolving solution is 8-15 mL.

[0038] In a specific embodiment, the dissolving solution used is a composite solution of Tris·HCl and SDS (sodium dodecyl sulfate) solution, and the volume ratio of Tris·HCl to SDS solution is 9:1-5:5; wherein the pH of Tris·HCl is 8-10, and the concentration of SDS solution is 1-5%.

[0039] In a specific embodiment, the dissolution time is 1-3 hours and the dissolution temperature is 30-40°C.

[0040] In a specific embodiment, the low-temperature high-speed centrifugation speed is 6000-8000 rpm, the centrifugation time is 3-5 min, and the centrifugation temperature is -5-0°C.

[0041] Step S2, spinning solution preparation:

[0042] Tussah silk gland protein and a sodium alginate solution with a mass concentration of 4% are compounded in a certain ratio, and Chinese herbal medicine is added into the composite solution to obtain a spinning solution.

[0043] In a specific embodiment, the Chinese herbal medicine used is one or more of Coptis chinensis, Taraxacum mongolicum, Artemisia argyi, Honeysuckle, and Isatis indigotica, which is a full-ingredient Chinese medicine formula; the amount of the Chinese herbal medicine is calculated by adding 3-5g of the Chinese herbal medicine to 10mL of the composite solution.

[0044] In a specific embodiment, the volume ratio of the tussah silk gland protein to the sodium alginate solution is 9:1-5:5.

[0045] Step S3, preparation of tussah silk gland protein fibers:

[0046] Microfluidic spinning technology is used to inject the spinning solution into the spinning chip, in which the core layer is the spinning solution and the skin layer is the curing agent, to prepare environmentally friendly and antibacterial tussah silk gland protein fibers.

[0047] In a specific embodiment, the curing agent used is CaCl2, citric acid or CaCl2 / citric acid, the CaCl2 concentration is 2-5%, the citric acid concentration is 5-10%, and the CaCl2 / citric acid volume ratio is 9:1-1:9.

[0048] In a specific embodiment, the microfluidic spinning core layer injection speed is 0.5-1 mL / h, and the skin layer injection speed is 3-8 mL / h.

[0049] In a specific embodiment, the microfluidic spinning chip used is a skin-core structure, but is not limited to the skin-core structure, and also includes a single-needle syringe, a multi-layer structure, and the like.

[0050] The following are specific embodiments of the present disclosure:

[0051] Example 1

[0052] Step S1, extracting tussah silk gland protein:

[0053] A fifth-instar living tussah silkworm was selected and directly dissected at 20°C to obtain the tussah silk gland, which was washed with distilled water for 3 times. Then, 4 g of the tussah silk gland was weighed and placed in 8 mL of a dissolving solution for dissolution. The dissolving solution was a complex solution of Tris·HCl with a pH of 8 and a 1% SDS solution, and the volume ratio of the two was 9:1. After dissolving at 40°C for 1 hour, the solution was centrifuged at -5°C with a centrifugal speed of 6000 rpm for 5 minutes to remove insoluble matter and obtain the tussah silk gland protein solution.

[0054] Step S2, spinning solution preparation:

[0055] Tussah silk gland protein and sodium alginate solution were compounded in a volume ratio of 9:1 to obtain 10 ml of a composite solution, and 3 g of Coptis chinensis powder was added to obtain a spinning solution.

[0056] Step S3, preparation of tussah silk gland protein fibers:

[0057] The microfluidic spinning technology is used to inject the spinning solution into a spinning chip with a skin-core structure. The curing agent is CaCl2 with a concentration of 2%. The core layer injection speed is 0.5 mL / h, and the skin layer injection speed is 3 mL / h. The environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine of Example 1 is prepared.

[0058] Example 2

[0059] Step S1, extracting tussah silk gland protein:

[0060] A five-instar living tussah silkworm was selected and directly dissected at 21°C to obtain the tussah silk gland, which was washed with distilled water for 4 times. Then, 5 g of the tussah silk gland was weighed and placed in 9 mL of a dissolving solution for dissolution, wherein the dissolving solution was a complex solution of Tris·HCl with a pH of 8 and a 2% SDS solution, and the volume ratio of the two was 8:2. After dissolving at 38°C for 1.5 hours, the solution was centrifuged at -4°C with a centrifugal speed of 6500 rpm and a centrifugal time of 4.5 minutes to remove insoluble matter and obtain a tussah silk gland protein solution.

[0061] Step S2, spinning solution preparation:

[0062] Tussah silk gland protein and sodium alginate solution were compounded in a volume ratio of 8:2 to obtain 10 ml of a composite solution, and 3 g of dandelion powder was added to obtain a spinning solution.

[0063] Step S3, preparation of tussah silk gland protein fibers:

[0064] The microfluidic spinning technology is used to inject the spinning solution into a spinning chip with a skin-core structure. The curing agent is CaCl2 with a concentration of 4%. The core layer injection speed is 0.6 mL / h, and the skin layer injection speed is 4 mL / h. The environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine of Example 2 is prepared.

[0065] Example 3

[0066] Step S1, extracting tussah silk gland protein:

[0067] A five-instar living tussah silkworm was selected and directly dissected at 22°C to obtain the tussah silk gland, which was washed with distilled water for 5 times. Then, 6 g of the tussah silk gland was weighed and placed in 10 mL of a dissolving solution for dissolution. The dissolving solution was a complex solution of Tris·HCl with a pH of 8 and a 3% SDS solution, and the volume ratio of the two was 7:3. After dissolving at 36°C for 2 hours, the solution was centrifuged at -3°C with a speed of 7000 rpm and a centrifugal time of 4 minutes to remove insoluble matter and obtain a tussah silk gland protein solution.

[0068] Step S2, spinning solution preparation:

[0069] Tussah silk gland protein and sodium alginate solution were compounded in a volume ratio of 7:3 to obtain 10 ml of a composite solution, and 4 g of wormwood powder was added to obtain a spinning solution.

[0070] Step S3, preparation of tussah silk gland protein fibers:

[0071] The microfluidic spinning technology was used to inject the spinning solution into a spinning chip with a skin-core structure. A CaCl2 / citric acid composite curing agent with a volume ratio of 8:2 was used. The core layer injection speed was 0.7 mL / h and the skin layer injection speed was 5 mL / h to prepare the environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine of Example 3.

[0072] Example 4

[0073] Step S1, extracting tussah silk gland protein:

[0074] A fifth-instar living tussah silkworm was selected and directly dissected at 23°C to obtain the tussah silk gland, which was washed with distilled water for 6 times. Then, 7 g of the tussah silk gland was weighed and placed in 11 mL of a dissolving solution for dissolution. The dissolving solution was a complex solution of Tris·HCl with a pH of 8 and a 4% SDS solution, and the volume ratio of the two was 6:4. After dissolving at 33°C for 2.5 hours, the solution was centrifuged at -2°C with a centrifugal speed of 7500 rpm and a centrifugal time of 3.5 minutes to remove insoluble matter and obtain a tussah silk gland protein solution.

[0075] Step S2, spinning solution preparation:

[0076] Tussah silk gland protein and sodium alginate solution were compounded in a volume ratio of 6:4 to obtain 10 ml of a composite solution, and 5 g of honeysuckle powder was added to obtain a spinning solution.

[0077] Step S3, preparation of tussah silk gland protein fibers:

[0078] The microfluidic spinning technology is used to inject the spinning solution into a spinning chip with a skin-core structure. The curing agent is 5% citric acid. The core layer injection speed is 0.8 mL / h, and the skin layer injection speed is 6 mL / h. The environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine of Example 4 is prepared.

[0079] Example 5

[0080] Step S1, extracting tussah silk gland protein:

[0081] A five-instar live tussah silkworm was selected and directly dissected at 24°C to obtain the tussah silk gland, which was washed with distilled water for 4 times. Then, 8 g of the tussah silk gland was weighed and placed in 15 mL of a dissolving solution for dissolution. The dissolving solution was a complex solution of Tris·HCl with a pH of 8 and a 5% SDS solution with a volume ratio of 5:5. After dissolving at 30°C for 3 hours, the solution was centrifuged at -1°C with a centrifugal speed of 8000 rpm for 3 minutes to remove insoluble matter and obtain a tussah silk gland protein solution.

[0082] Step S2, spinning solution preparation:

[0083] Tussah silk gland protein and sodium alginate solution were compounded in a volume ratio of 5:5 to obtain 10 ml of a composite solution, and 3 g of Radix Isatidis powder was added to obtain a spinning solution.

[0084] Step S3, preparation of tussah silk gland protein fibers:

[0085] The microfluidic spinning technology was used to inject the spinning solution into a spinning chip with a skin-core structure. A CaCl2 / citric acid composite curing agent with a volume ratio of 5:5 was used. The core layer injection speed was 1.0 mL / h and the skin layer injection speed was 8 mL / h to prepare the environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine of Example 5.

[0086] The antibacterial performance parameters of the above embodiments are shown in Table 1:

[0087] Table 1 Antibacterial properties of environmentally friendly antibacterial tussah silk gland protein fibers of Chinese herbal medicine

[0088]

[0089] As shown in Table 1, the environmentally friendly antibacterial tussah silk gland protein fibers based on Chinese herbal medicines in Examples 1-5 have good antibacterial properties, and the antibacterial rates can reach more than 98%, and the antibacterial properties of the fibers against Staphylococcus aureus are better than those against Escherichia coli. This indicates that the addition of Chinese herbal medicines can improve the antibacterial properties of the fibers, and the environmentally friendly antibacterial tussah silk gland protein fibers containing Chinese herbal medicines can be obtained by the present invention.

[0090] Figure 1 and Figure 2 The inhibition zones of the fibers of Example 1 against Staphylococcus aureus and Escherichia coli are shown in Table 1. Figure 1 and Figure 2 It can be seen that the diameter of the inhibition zone is 3mm±0.02mm.

[0091] It can be seen from the experimental data of the above Examples 1-5 that the antibacterial rate of the environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine disclosed in the present invention against Staphylococcus aureus and Escherichia coli is higher than 98.99%, so the fiber and fabric prepared by the method of the present invention have good antibacterial and health-care properties.

[0092] Then, the materials used for preparing the fiber disclosed in the present invention, namely, tussah silk gland protein and sodium alginate, are both natural biological materials, are biodegradable, and have good biocompatibility.

[0093] In addition, the process used is green and environmentally friendly, with no wastewater discharge, and no adhesives, cross-linking agents or functional finishing agents are required during the preparation process.

[0094] In summary, the environmentally friendly antibacterial tussah silk gland protein fiber of Chinese herbal medicine obtained by the method of the present invention has the characteristics of high content of effective ingredients of Chinese herbal medicine and strong durability, and at the same time, the process is simple and easy to control, and it is easy to realize large-scale production.

[0095] Although the present invention has been described above, the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely illustrative and not restrictive. Many modifications made by technicians in this field under the inspiration of the present invention without departing from the purpose of the present invention are all within the protection of the present invention.

Claims

1. A method for preparing environmentally friendly antibacterial tussah silk gland protein fiber, characterized in that: include: Extracting tussah silk gland protein; Adding Chinese herbal medicine to the composite solution of tussah silk gland protein and sodium alginate to obtain a spinning solution; The spinning solution is spun by a microfluidic spinning method to obtain environmentally friendly antibacterial tussah silk gland protein fibers.

2. The method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber according to claim 1, characterized in that: The Chinese herbal medicine is one or a mixture of coptis root, dandelion, wormwood, honeysuckle, and isatis root, and the mass ratio of the Chinese herbal medicine to the tussah silk gland protein is 1:3 to 1:

1. 。 3. The method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber according to claim 1 or 2, characterized in that: The method for extracting tussah silk gland protein comprises: The fifth instar tussah silkworm is dissected alive to obtain the tussah silk gland, the cleaned tussah silk gland is dissolved with a dissolving solution, and the insoluble matter therein is removed to obtain the tussah silk gland protein.

4. The method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber according to claim 3, characterized in that: The dissolving solution is a complex solution of Tris·HCl with a pH of 8 to 10 and an SDS solution with a concentration of 1 to 5%, and the volume ratio of the Tris·HCl to the SDS solution is 9:1 to 5:5; The dissolution time is 1 to 3 hours, and the dissolution temperature is 30 to 40°C; The mass ratio of the tussah silk gland to the dissolving solution is 1:1 。 5. The method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber according to claim 4, characterized in that: The environmental temperature for dissecting the live fifth-instar tussah silkworm is 20-25° C., and the silk glands of the tussah silkworm are cleaned 3-6 times with distilled water; The insoluble matter is removed by centrifugation, the centrifugal speed is 6000-8000 rpm, the centrifugal time is 3-5 minutes, and the centrifugal temperature is -5-0°C.

6. The method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber according to claim 2, characterized in that: The composite volume ratio of the tussah silk gland protein to the sodium alginate solution with a mass concentration of 4% is 9:1 to 5:

5.

7. The method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber according to claim 6, characterized in that: The microfluidic spinning method comprises: The spinning solution is injected into a spinning chip, wherein the core layer is the spinning solution and the skin layer is the curing agent; The core layer injection speed is 0.5-1 mL / h, and the skin layer injection speed is 3-8 mL / h.

8. The method for preparing the environmentally friendly antibacterial tussah silk gland protein fiber according to claim 7, characterized in that: The curing agent is a CaCl2 solution with a mass concentration of 2-5%, a citric acid solution with a mass concentration of 5-10%, or a CaCl2 / citric acid composite curing agent, wherein the composite curing agent is a mixture of a CaCl2 solution with a mass concentration of 2-5% and a citric acid solution with a mass concentration of 5-10% in a volume ratio of 9:1 to 1:9; and / or, The spinning chip is a skin-core structure, a single needle syringe or a multi-layer structure.

9. An environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine, characterized in that: The fiber is prepared by the method according to any one of claims 1 to 8.

10. A fabric, characterized in that: The fiber is woven from the environmentally friendly antibacterial tussah silk gland protein fiber based on Chinese herbal medicine as described in claim 9.

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