CN102644203A - Method for improving antibacterial durability of ramie by laccase/phenols processing mode - Google Patents

Abstract

The invention discloses a method for improving the antibacterial durability of ramie fiber by adopting a laccase/phenolic substance treatment method. The method mainly includes the following steps: the process conditions for treating ramie pulp with laccase/phenolic substance and the fiber treatment Ramie fibers with enhanced antimicrobial persistence were obtained. Compared with the untreated ramie fiber, the ramie fiber after the laccase/phenolic substance treatment in the present invention has increased the antibacterial effect to bacteria and mold, and also has good washability and antibacterial persistence; Compared with the hemp fiber obtained by other methods, the treated ramie fiber belongs to the non-dissolution type, and it still maintains a good antibacterial effect with the increase of washing times, avoiding the direct contact between the antibacterial agent and the human body, and not only improving the antibacterial properties of the hemp fiber itself. The antibacterial effect also endows the hemp fiber with the inhibitory effect on other bacteria species, so that the hemp fiber has good washability and antibacterial persistence. The treatment method of the invention is simple and easy to operate, and provides a new treatment method for improving the washability and antibacterial durability of the hemp fiber.

Description

Method for Improving Antibacterial Persistence of Ramie Fiber by Laccase/Phenolic Substance Treatment

technical field

The invention belongs to the field of textiles and relates to antibacterial treatment of ramie fibers, in particular to a method for improving the antibacterial durability of ramie fibers by using laccase/phenolic substance treatment.

Background technique

In recent years, with the improvement of people's living standards and the influence of health concepts, people's requirements and tastes for daily necessities have also been continuously improved; especially in the textile field, it has good antibacterial properties, good anti-mold and anti-odor functions, and good durability. Antibacterial textiles have attracted the attention of people from all walks of life, especially hemp fiber, which has good antibacterial effect and natural excellent properties such as moisture absorption, breathability, anti-ultraviolet radiation, and no static electricity, and is widely loved by consumers. However, although the hemp fiber has the above-mentioned good properties, its antibacterial durability and washability are not satisfactory, and the textile itself is a good parasitic place for microorganisms, so its washability and antibacterial durability have always been studied by people. hotspot.

At present, there are many reports on the processing methods of antibacterial fabrics at home and abroad. Generally speaking, they can be divided into the following two basic methods: 1. Spinning modification method: first prepare antibacterial fibers, and then make various antibacterial fabrics; 2. , Post-finishing method: The fabric is post-treated with an antibacterial agent to obtain antibacterial properties. In comparison, the antibacterial effect of the fabric obtained by the spinning modification method is relatively long-lasting and has good washability, but the production process of the antibacterial fiber is more complicated, and the requirements for the antibacterial agent are also higher. Blended silk method and composite spinning method; the processing process of finishing method is relatively simple, but the antibacterial effect and washing resistance of the resulting fabric are poor. In recent years, the proportion of fiber-modified fabrics in antibacterial textiles has been increasing year by year. According to the development trend, the research on antibacterial textile fibers has great potential and application value.

Ramie fiber itself has a certain antibacterial effect on microorganisms such as Escherichia coli, Bacillus subtilis and Aspergillus niger, but it will weaken and disappear with the increase of washing times. Therefore, improving the antibacterial persistence and washability of hemp fiber is an urgent problem to be developed and solved. Phenolic substances have a certain antibacterial effect due to their structural characteristics, and laccase has the characteristics of catalyzing the oxidation of phenolic substances. Properly using the advantages of both to treat ramie fibers can improve the antibacterial persistence of ramie fibers on the one hand, and on the other hand Broaden the scope of application of laccase in the textile field.

Studies have shown that phenolic substances extracted from some natural products can better resist the growth of microorganisms, and laccase is a copper-containing polyphenol oxidase that can catalyze the oxidation of various phenolic and aromatic amine substrates, thereby endowing fibers with some features. According to the following literature reports: 1. Aracri, E., Vidal, T. laccase-induced coupling of natural phenols ontosisal fibers (C). ISWFPC, 2009: 46-48, the research report in the article shows that laccase/HBT and laccase/ After CLD treatment of sisal fibers, the selected phenolic substances are combined on the surface of sisal fibers under the action of laccase, showing an increase in fiber Kappa value and brightness; 2. Fillat, A., et al.Nature mediators in flax pulp deligificationby laccase (C). IPBC, 2008: 247 article report, some natural mediators can be grafted to the surface of hemp fiber under the effect of laccase; 3, Fillat, A., Gallardo, O., Vidal, T.Evaluation Ofnatural mediators for developing antimicrobial properties to pulp fibers (C). ISWFPC, 2009: 46 shows that laccase/p-coumaric acid treats hemp fibers, and p-coumaric acid can be grafted to the surface of hemp fibers to endow fibers with certain characteristics. Aracri, E., et al. Enzymatic grafting of simple phenols on flax and sisal pulpfibres using laccases (J). Biotechnol, 2010: 8211-8216 showed that some small molecule phenols processed sisal under the action of laccase After treatment, these phenolic substances are chemically bonded with the sisal fiber to endow the sisal fiber with new characteristics.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for improving the antibacterial durability of ramie fibers by using laccase/phenolic substance treatment.

For realizing the purpose of the present invention, the technical scheme adopted is:

A method for improving the antibacterial persistence of ramie fiber by adopting laccase/phenols treatment mode, the steps are:

(1) ramie fiber adopts traditional chemical degumming process to carry out degumming process;

(2) Select phenolic substances to have good inhibitory effect on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella and Aspergillus niger, and dissolve the phenolic substances with ethanol at a concentration of 0.2%-0.3%;

(3) Get the above-mentioned ramie fiber after degumming, adjust the slurry concentration to be 3%, and the pH value of the slurry is 5, add phenolic substances dissolved in ethanol in advance, add laccase after fully stirring with air for 5 minutes, place at temperature In a constant temperature shaker at 50°C, treat at 100r/min for 4h;

(4) After the treatment, the hemp fiber was washed with water and dried to obtain ramie fiber.

Moreover, the phenolic substances include isoeugenol, p-coumaric acid and vanillin.

Moreover, the amount of phenolic substances added in the step (3) is 3.5% relative to the dry pulp, and the amount of laccase added is 18 U/g relative to the dry pulp.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1, the present invention selects some natural phenolic substances and laccase to process ramie fiber by fiber modification technology, through the ramie fiber after laccase/phenolic substance treatment, phenolic substance and ramie fiber produce chemical bonds to connect and retain its antibacterial group , not only can broaden the antibacterial range of ramie fiber itself to microorganisms, but also the modified ramie fiber is non-dissolution type, with good washability and antibacterial persistence

2, compared with untreated ramie fiber, the ramie fiber after laccase/phenolic substance process in the present invention has increased the antibacterial effect to bacteria and mould, has good washability and antibacterial persistence, and is different from that in the textile industry Compared with the hemp fiber obtained by other methods, not only the treated ramie fiber is non-dissolving type, but also maintains a good antibacterial effect with the increase of washing times, avoiding the direct contact of antibacterial agents with the human body, and not only improving the antibacterial effect of the hemp fiber. The antibacterial effect of itself also endows the hemp fiber with the inhibitory effect on other bacterial species.

3. The present invention utilizes the characteristics of the antibacterial properties of phenolic substances, and cooperates with laccase to treat ramie fibers, thereby improving the washability and antibacterial durability of hemp fibers. The processing method is simple and easy to operate. In order to improve the washability of hemp fibers And antibacterial persistence provides a new treatment method, which is of great significance for the production of antibacterial textiles and broadening the application field of laccase.

Detailed ways

The embodiments of the present invention will be described in detail below. It should be noted that the embodiments are illustrative, not restrictive, and cannot limit the protection scope of the present invention.

Example 1:

Raw materials used:

Isoeugenol (ISO): purchased from Sigma-Aldrich.

Ramie fiber: from Shaanxi Province.

Laccase: provided by Novozymes, trade name NOVOZYM-51003, enzyme activity 1070U/g.

A method for improving the antibacterial persistence of ramie fiber by adopting laccase/phenols treatment mode, the steps are:

(1) The degumming treatment of ramie fiber adopts traditional chemical degumming process to carry out: add 1% sulfuric acid with the bath ratio of 1: 12 to the original hemp, handle 1h in 50 ℃ of water baths and finish the pickling process, after washing, the fiber is treated with bath ratio 1: Add 5% sodium hydroxide and 4% sodium silicate at a ratio of 12, treat in a constant temperature water bath at 100°C for 1.5h, wash with water again, add 12% sodium hydroxide, 4% sodium silicate and Treat 2% sodium tripolyphosphate in a constant temperature water bath at 100°C for 2 hours to complete the second boiling process. After washing, soak the hemp fibers in 2g/L sulfuric acid solution at room temperature with a bath ratio of 1:20 for 5 minutes, and finally wash with water. use;

(2) Evaluation of the antibacterial effect of isoeugenol itself on bacteria. After dimethyl sulfoxide was dissolved, the Oxford cup method was used to detect the antibacterial zone size of isoeugenol on Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Salmonella respectively. , the used isoeugenol has a good inhibitory effect on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella and Aspergillus niger, the isoeugenol is dissolved in ethanol at a concentration of 0.2%-0.3%, and set aside;

(3) get the above-mentioned ramie fiber after degumming, adjust the slurry slurry with water to be 3% thick, and the slurry pH value is 5, add the isoeugenol that dissolves with ethanol in advance, the addition of isoeugenol is respectively relative to the absolute dry pulp 3.5%; add laccase after fully stirring with air for 5 minutes, the amount of laccase added is 18U/g relative to the absolute dry pulp, put it in a constant temperature shaker with a temperature of 50°C, and treat it at 100r/min for 4 hours.

(4) After the treatment, the hemp fiber was washed with water and dried to obtain the modified ramie fiber.

The modified ramie fibers obtained above were subjected to antibacterial test analysis and washability test analysis respectively, and the measurement results are shown in Table 1 and Table 2, respectively.

Table 1

Note: The experiment was repeated 3 times to take the average value

From the data in Table 1, it can be known that ramie fiber itself has a certain antibacterial effect on Escherichia coli, Bacillus subtilis and Aspergillus niger. It also has good antibacterial effect on Staphylococcus aureus and Salmonella.

The ramie fiber before and after treatment was washed 20 times to detect the change of its antibacterial rate. As can be seen from the data in Table 2, the antibacterial effect of untreated ramie fiber on different bacterial species was significantly reduced after repeated washing. , and the antibacterial rate of ramie fiber treated with laccase/isoeugenol is reduced after 20 times of washing, but it still has good antibacterial effect on different bacterial species, reaching the level of people's understanding of textile washability and antibacterial properties. Persistence requirements.

Table 2

Note: 1 is blank sample, 2 is laccase/isoeugenol treated sample

Example 2:

A method for improving the antibacterial persistence of ramie fiber by using laccase/phenolic substance treatment mode, but the selected phenolic substance adopts p-coumaric acid instead of isoeugenol, the operation steps in the method, each parameter, p-coumaric acid and The amount of laccase, the process conditions of laccase/p-coumaric acid treatment of ramie slurry and the antibacterial performance and washing resistance test method of ramie fiber are the same as in Example 1, and the test results are shown in Table 3 and Table 4 respectively.

As can be seen from the data in Table 3, compared with the untreated ramie fiber, the antibacterial effect of the ramie fiber treated with laccase/p-coumaric acid on different experimental strains was higher than that of the untreated sample. The antibacterial rates of Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella and Aspergillus niger were 29.55%, 39.56%, 44.25%, 26.92% and 52.76%, respectively.

table 3

Note: The experiment was repeated 3 times to take the average value

After 20 times of washing, the antibacterial effect of untreated ramie fiber on the experimental strains was greatly reduced, while the ramie fiber treated with laccase/p-coumaric acid was still effective on the experimental strains after 20 times of washing. It has a good antibacterial effect and meets people's requirements for textile washability and antibacterial durability.

Table 4

Note: 1 is blank sample, 2 is laccase/p-coumaric acid treated sample

Example 3:

A method for improving the antibacterial persistence of ramie fiber by using laccase/phenolic substance treatment mode, but the selected phenolic substance uses vanillin instead of isoeugenol, the operation steps in the method, each parameter, the consumption of vanillin and laccase , the process conditions of laccase/vanillin treatment of ramie slurry and the antibacterial performance and washability test method of ramie fiber are the same as in Example 1, and the test results are shown in Table 5 and Table 6 respectively.

As can be seen from the data in Table 5, compared with the untreated ramie fiber, the antibacterial effect of the ramie fiber treated with laccase/vanillin on different experimental strains was higher than that of the untreated sample. The antibacterial rates of coccus, Escherichia coli, Bacillus subtilis, Salmonella and Aspergillus niger were 31.04%, 41.25%, 40.58%, 28.32% and 55.36%, respectively.

table 5

Note: The experiment was repeated 3 times to take the average value

After 20 times of washing, the antibacterial effect of untreated ramie fiber on the experimental strains was greatly reduced, while the ramie fiber treated with laccase/vanillin still had good antibacterial effect on the experimental strains after 20 times of washing. The antibacterial effect meets people's requirements for textile washability and antibacterial durability.

Table 6

Note: 1 is blank sample, 2 is laccase/vanillin treated sample

The modified ramie fiber obtained above is carried out to antibacterial test analysis and washability test analysis respectively, adopts the change of the ramie fiber antibacterial performance after the flask oscillation method is detected to handle, and concrete operation steps are as follows:

1. Take freshly cultured representative strains (Aspergillus niger cultured for 72 hours) after 24 hours of culture, and dilute it into a bacterial suspension with a bacterial count of 1×10 ⁶ -2×10 ⁶ cfu/mL. Take an appropriate amount of bacterial suspension and 1 g of absolute Add the dried processed ramie fiber into a 250mL Erlenmeyer flask containing 70mL of PBS buffer solution. At this time, the concentration of the bacterial suspension is 1×10 ⁴ -2×10 ⁴ cfu/mL, and then place the Erlenmeyer flask in a constant temperature shaker for 37 Shake at 220r/min for 1h at °C.

2. After treatment, take 0.5mL of the bacterial suspension in the triangular flask and add it to a sterile petri dish (diameter 90mm), inoculate 3 petri dishes with each bacterial suspension, and then add about 18mL of beef extract that has been melted in advance and cooled to about 45°C Peptone culture medium, after shaking well, put it flat on the aseptic operating table. After the culture medium is cooled, turn the culture dish over and place it in a constant temperature incubator at 37°C for 48 hours to count colonies (aspergillus niger is cultivated at 30°C for 72 hours), and the experiment is repeated 3 times. The average value was taken every time to detect the change of antibacterial properties of ramie fiber after treatment.

3. According to GB8629-2001, the ramie fibers before and after treatment were washed 5 times, 10 times, 15 times, and 20 times respectively, and then the antibacterial rate of the fibers was detected according to the above-mentioned flask oscillation method, and then the antibacterial properties of the ramie fibers before and after treatment were evaluated. Persistence and washability. The test results show that the ramie fiber treated with laccase/phenolic substances has improved antibacterial effect on Escherichia coli, Bacillus subtilis and Aspergillus niger, and also has good inhibitory effect on Staphylococcus aureus and Salmonella. After 20 times of washing After treatment, the bacteriostatic effect of ramie fiber on various strains decreased slightly, and the bacteriostatic rate varied by about 10%.

Principle of the present invention:

In the modified ramie fiber, the phenolic substances are combined on the surface of the fiber without dissolution, and the ability of the ramie fiber to inhibit the growth of microorganisms is improved.

Claims (3)

1. a kind of method that adopts laccase/phenols treatment mode to improve ramie fiber antibacterial persistence, is characterized in that: step is: (1) ramie fiber adopts traditional chemical degumming process to carry out degumming process; (2) Select phenolic substances to have good inhibitory effect on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella and Aspergillus niger, and dissolve the phenolic substances with ethanol at a concentration of 0.2%-0.3%; (3) Get the above-mentioned ramie fiber after degumming, adjust the slurry concentration to be 3%, and the pH value of the slurry is 5, add phenolic substances dissolved in ethanol in advance, add laccase after fully stirring with air for 5 minutes, place at temperature In a constant temperature shaker at 50°C, treat at 100r/min for 4h; (4) After the treatment, the hemp fiber was washed with water and dried to obtain ramie fiber. 2. the method for improving the antibacterial persistence of ramie fiber by adopting laccase/phenolic substance treatment mode according to claim 1, characterized in that: said phenolic substance comprises isoeugenol, p-coumaric acid and vanillin. 3. the method that adopts laccase/phenolic substance treatment mode to improve the antibacterial persistence of ramie fiber according to claim 1, is characterized in that: the addition of phenolic substance in described step (3) is respectively with respect to dry pulp It was 3.5%, and the addition amount of laccase was 18U/g relative to the absolute dry pulp.