A complex enzyme preparation for fabric low-temperature refining, a treating solution and a method

Abstract

This invention belongs to the field of textile dyeing and finishing technology, and provides a composite enzyme preparation, treatment solution, and method for low-temperature refining of fabrics. The composite enzyme preparation includes polysaccharide cleaving monooxygenase, laccase, glucose oxidase, pectinase, and xylanase. This composite enzyme preparation, through the combined action of polysaccharide cleaving monooxygenase and laccase, oxidatively destroys the lignin-cellulose cross-linked structure on the surface of cottonseed hulls, providing substrate channels for pectinase and xylanase. The two stages synergistically lead to the effective disintegration of the cottonseed hull structure, resulting in a removal effect superior to single enzyme systems. The in-situ continuous generation of H2O2 by glucose oxidase replaces one-time or stepwise direct addition, maintaining a low-concentration steady state throughout the process. This matches the Km value of LPMO, effectively avoiding oxidative damage to the copper active sites of LPMO by H2O2 and ensuring the continuous catalytic activity of LPMO within the process window. The H2O2 supply, electron donor supply, oxidative cleavage, and main hydrolysis functions are decoupled, resulting in a clear mechanism.

Description

Technical Field

[0001] This invention belongs to the field of textile dyeing and finishing technology, specifically relating to a compound enzyme preparation, treatment solution and method for low-temperature refining of fabrics. Background Technology

[0002] Cotton refining is a fundamental step in dyeing and finishing. Its core purpose is to remove natural impurities such as pectin, waxes, nitrogenous substances, and cottonseed hulls from the surface of cotton fibers, providing fabrics with good wettability and whiteness for subsequent dyeing and printing. Currently, the mainstream refining process still mainly relies on high-temperature concentrated alkali scouring, which has drawbacks such as high energy consumption, high pollution, fiber damage, and dependence on harsh chemical conditions for cottonseed hull removal.

[0003] In recent years, bio-enzyme refining technology has attracted widespread attention due to its mild conditions and water-saving and emission-reduction benefits. However, existing refining complex enzymes mainly target pectin and waxes, lacking effective degradation methods for cottonseed hulls, which are mainly composed of lignin. Recent studies have found that polysaccharide lysing monooxygenase (LPMO) can introduce active functional groups such as carboxyl groups onto the surface of cellulose fibers and can synergistically process cotton fibers with cellulase. However, the optimal pH for commonly used alkaline pectinase is 8.0-9.0, while LPMO exhibits insufficient activity and stability under alkaline conditions, making them incompatible under the same pH conditions and resulting in limited pH adaptability. Furthermore, LPMO requires a low concentration of H2O2 as a co-substrate (Km values ​​are typically in the 1-10 µM range), but the concentration of directly added H2O2 is difficult to control precisely. High concentrations of H2O2 can oxidatively damage the copper active sites of LPMO, leading to irreversible enzyme inactivation. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems in existing cotton fabric enzymatic refining technologies, such as incomplete removal of cottonseed hulls, incompatibility of pH conditions between LPMO and pectinase, and difficulty in coordinating H2O2 supply and enzyme activity protection.

[0005] Therefore, the present invention provides a compound enzyme preparation for low-temperature refining of fabrics, comprising polysaccharide cleaving monooxygenase, laccase, glucose oxidase, pectinase, and xylanase.

[0006] Specifically, by weight fraction, the compound enzyme preparation comprises 1-20 parts polysaccharide lysing monooxygenase, 5-25 parts laccase, 1-10 parts glucose oxidase, 30-70 parts pectinase, 5-20 parts xylanase, and 0-10 parts cellulase.

[0007] Specifically, the compound enzyme preparation, by weight fraction, comprises 5-10 parts polysaccharide cleavage monooxygenase, 10-15 parts laccase, 3-6 parts glucose oxidase, 40-60 parts pectinase, 5-15 parts xylanase, and 1-5 parts cellulase.

[0008] Specifically, the activity of polysaccharide monooxygenase in the above-mentioned compound enzyme preparation is 70-90 U / g, laccase activity is 500-5000 U / g, glucose oxidase activity is 1000-10000 U / g, pectinase activity is 300-2000 U / mL, xylanase activity is 5000-100000 U / g, and cellulase activity is 2000-200000 U / mL.

[0009] The present invention also provides a low-temperature refining treatment solution for fabrics, comprising a nonionic surfactant, a penetrant, glucose, water, and any one of the above-mentioned compound enzyme preparations.

[0010] Specifically, each liter of the fabric low-temperature refining solution includes 2-4 g / L of compound enzyme preparation, 2-4 g / L of nonionic surfactant, and 0.5-2 mM glucose.

[0011] Specifically, the pH of the above-mentioned low-temperature refining solution for fabrics is 6.5-7.0.

[0012] The present invention also provides a method for low-temperature refining of fabrics, comprising the following steps: preparing the treatment solution described in any one of the above; immersing the fabric to be treated in the treatment solution and heating it to carry out an oxidation reaction; adding an alkaline solution to the reaction system to adjust the pH to 8.0-8.5, while simultaneously heating it to carry out a hydrolysis reaction; inactivating enzymes; and washing the fabric with water until it is neutral.

[0013] Specifically, the ratio of the fabric to be treated to the treatment solution is 1:10-30.

[0014] Specifically, the oxidation reaction conditions are: heating to 50-55℃ and reacting for 30-35 minutes; the hydrolysis reaction conditions are: heating to 60-65℃ and reacting for 35-40 minutes.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0016] The composite enzyme preparation for low-temperature refining of fabrics provided by this invention utilizes a combination of polysaccharide monooxygenase and laccase to oxidatively destroy the lignin-cellulose cross-linked structure on the surface of cottonseed hulls, providing substrate channels for pectinase and xylanase. This two-stage synergy effectively disintegrates the cottonseed hull structure, resulting in superior removal efficiency compared to single enzyme systems. Glucose oxidase is used to continuously generate H2O2 in situ, replacing one-time or stepwise direct addition, maintaining a low-concentration steady state throughout the process. Matching the Km value with LPMO, this effectively avoids oxidative damage to the copper active sites of LPMO by H2O2, ensuring the continuous catalytic activity of LPMO within the 60-90 minute process window. The H2O2 supply, electron donor supply, oxidative cleavage, and main hydrolysis functions are decoupled, resulting in a clear mechanism.

[0017] The low-temperature refining method for fabrics provided by this invention employs a two-stage pH treatment process under mild conditions: an oxidation stage at pH 6.5-7.0 and a hydrolysis stage at pH 8.0-8.5. This avoids the predicament of inhibited activity of some enzymes under a single pH condition, ensuring that all enzymes function under optimal conditions. The two-stage process can be completed in the same treatment bath by adjusting pH and temperature in between, without the need for solution changes or intermediate water washing, making operation simple. The entire process is conducted at a temperature of 50-65℃, far lower than the 80-100℃ of traditional alkali refining, significantly reducing energy consumption.

[0018] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the LPMO catalytic activity changing with time at different temperatures in the embodiments of the present invention.

[0020] Figure 2 These are curves showing the change in LPMO catalytic activity over time under different H2O2 supply methods in the embodiments of the present invention. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Although representative embodiments of the present invention have been described in detail, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the embodiments, but should be defined by the appended claims and their equivalents.

[0022] This invention provides a compound enzyme preparation for low-temperature refining of fabrics, comprising polysaccharide lysing monooxygenase (LPMO), laccase, glucose oxidase (GOx), pectinase, xylanase, and cellulase.

[0023] Specifically, by weight fraction, the compound enzyme preparation comprises 1-20 parts of polysaccharide-lysing monooxygenase, 5-25 parts of laccase, 1-10 parts of glucose oxidase, 30-70 parts of pectinase, 5-20 parts of xylanase, and 0-10 parts of cellulase. Preferably, it comprises 5-10 parts of polysaccharide-lysing monooxygenase, 10-15 parts of laccase, 3-6 parts of glucose oxidase, 40-60 parts of pectinase, 5-15 parts of xylanase, and 1-5 parts of cellulase.

[0024] Furthermore, the polysaccharide cleavage monooxygenase activity in the compound enzyme preparation is 70-90 U / g, laccase activity is 500-5000 U / g, glucose oxidase activity is 1000-10000 U / g, pectinase activity is 300-2000 U / mL, xylanase activity is 5000-100000 U / g, and cellulase activity is 2000-200000 U / mL.

[0025] The present invention also provides a low-temperature refining treatment solution for fabrics, comprising a nonionic surfactant, a penetrant, glucose, water, and a composite enzyme preparation as described above. Preferably, the pH of the low-temperature refining treatment solution for fabrics is adjusted to 6.5-7.0 using citric acid or NaOH.

[0026] Specifically, each liter of the fabric low-temperature refining solution includes 2-4 g / L of compound enzyme preparation, 2-4 g / L of nonionic surfactant, and 0.5-2 mM glucose.

[0027] Among them, the catalytic cycle of LPMO depends on its copper active center, and in the presence of an electron donor, Cu 2+ Reduced to Cu + Subsequently, activated H2O2 generates a highly active copper-oxygen intermediate that extracts hydrogen atoms from the CH bonds of lignin or cellulose chains, achieving hydroxylation and ultimately forming a carboxyl group. In the use of compound enzyme preparations, LPMO's electron donor is provided by phenolic compounds produced by laccase degradation of lignin; H2O2 is continuously generated in situ by glucose oxidase catalyzing glucose oxidation, maintaining a low-concentration steady state (1-10 µM level) throughout the process, avoiding localized high-concentration oxidative damage caused by direct addition of H2O2. LPMO introduces active functional groups such as carboxyl groups by oxidatively cleaving the lignin-cellulose cross-linked structure on the surface of cottonseed hulls, providing new sites of action for pectinase and xylanase, increasing substrate accessibility, and forming a cascade synergistic effect.

[0028] Laccase plays a dual role in this compound enzyme preparation. First, it directly oxidizes and degrades the lignin components in cottonseed hulls, loosening the cross-linked structure and releasing low molecular weight phenolic compounds. Second, the released phenolic products act as electron donors for LPMO, continuously activating the catalytic cycle of LPMO without the need for external chemical reducing agents such as ascorbic acid.

[0029] Glucose oxidase catalyzes the oxidation of β-D-glucose to gluconic acid and H2O2. The reaction rate depends on the glucose concentration and the amount of GOx used, enabling a sustained low-concentration release of H2O2. A trace amount of glucose (final concentration 0.5-2 mM) is added to the treatment solution as a substrate, and GOx is supplied with H2O2 at a constant low rate throughout the refining process, maintaining the steady-state concentration of H2O2 in the system at 1-10 µM, matching the Km value of LPMO and avoiding oxidative damage to the enzyme's active site.

[0030] Pectinase acts on the α-1,4 glycosidic bonds of pectin, hydrolyzing them into soluble pectic acid, thus disrupting the adhesive function of pectin between fibers and waxes. Once the pectin is removed by hydrolysis, the binding force between the waxes and fibers is lost, and the waxes can be removed through emulsification during subsequent washing.

[0031] Xylanase hydrolyzes the xylan backbone in the hemicellulose component of cottonseed hulls, degrading it into xylo-oligosaccharides. This disrupts the structural integrity of the cottonseed hulls and, in synergy with laccase-lignin degradation and pectinase, accelerates the disintegration and removal of cottonseed hulls.

[0032] Cellulase is an optional component in compound enzyme preparations, and its dosage must be strictly controlled. A small amount of endocellulase can act on exposed cellulose microfibrils in cottonseed hulls, synergistically stripping away cottonseed hull fragments, but excessive hydrolysis should be avoided to prevent a decrease in the strength of the fiber matrix.

[0033] This invention divides the enzyme system in a compound enzyme preparation into an oxidation module and a hydrolysis module:

[0034] In the oxidation stage, LPMO, laccase, and GOx work together. Laccase oxidizes lignin to release phenolic electron donors; GOx continuously generates low-concentration H2O2 for LPMO to use; LPMO oxidizes and cleaves the lignin-cellulose cross-linked structure, introducing carboxyl groups on the fiber surface to increase the accessibility of subsequent hydrolytic enzymes.

[0035] In the hydrolysis stage, pectinase, xylanase, and microcellulase work together. Pectinase hydrolyzes pectin and breaks down wax adhesion; xylanase degrades hemicellulose and weakens the cottonseed hull structure; and cellulase removes exposed microfibrils and assists in hull shedding.

[0036] The oxidation stage opens up substrate channels for the hydrolysis stage, and the hydrolysis stage expands and excavates these channels to jointly loosen and remove cottonseed hulls.

[0037] The present invention also provides a method for low-temperature refining of fabrics, comprising the following steps:

[0038] Prepare the above treatment solution;

[0039] Add the fabric to be treated at a bath ratio of 1:10-30, heat to 50-55℃ for oxidation reaction for 30-35 minutes. During this period, glucose oxidase continuously converts glucose into H2O2, maintaining a low concentration of H2O2 in the system (steady state 1-10 µM), driving LPMO to undergo oxidative cleavage, and laccase simultaneously degrades lignin to release phenolic electron donors.

[0040] Slowly add Na2CO3 or other weak alkaline solution to the reaction system to adjust the pH to 8.0-8.5, and at the same time raise the temperature to 60-65℃ to carry out the hydrolysis reaction for 35-40 minutes. Pectinase and xylanase perform hydrolysis functions. Pectinase hydrolyzes pectin, xylanase degrades hemicellulose, and cellulase assists in the removal.

[0041] Heat the fabric to 80-90℃ to inactivate the enzymes, and then wash it with conventional hot water and cold water until it is neutral.

[0042] The effects of the composite enzyme preparation, treatment solution, and method for low-temperature refining of fabrics of the present invention are studied below through specific embodiments. All indicators in the embodiments of the present invention were detected using conventional testing methods in the art, and will not be elaborated upon further.

[0043] Example 1:

[0044] This embodiment provides a compound enzyme preparation for low-temperature refining of fabrics. The formulation composition is shown in Table 1 by weight.

[0045] Table 1. Formulation of compound enzyme preparations

[0046]

[0047] Based on the above-mentioned compound enzyme preparation, this embodiment also provides a low-temperature refining treatment solution for fabrics, comprising 3 g / L compound enzyme preparation, 2 g / L Tween-80, 2 g / L penetrant JFC, 1 mM glucose, and the remainder being water.

[0048] Based on the above-mentioned processing liquid, this embodiment also provides a method for low-temperature refining of fabrics, including the following steps:

[0049] Prepare the above treatment solution with pH 6.8 and add it to pure cotton knitted fabric at a bath ratio of 1:20;

[0050] Heat to 55℃ and allow the oxidation reaction to proceed for 30 minutes.

[0051] Slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes;

[0052] Heat the fabric to 85°C to inactivate the enzymes, then wash it with water until it is neutral.

[0053] After treatment, the capillary effect of the fabric was 11.8 cm / 30 min, the cottonseed hulls were basically removed (residual score +), the whiteness reached 79, and the fabric strength retention rate was 96%.

[0054] Example 2:

[0055] This embodiment verifies the effect of different temperatures on LPMO activity, as detailed below.

[0056] Prepare the detection system (1 mL): 0.2 U / ml LPMO (AA9 family, 90 U / g), 3 mM 2,6-DMP, and the remainder is buffer solution.

[0057] Buffer solution: 100 mM phosphate buffer, pH 7.0;

[0058] Temperature: 40℃ & 50℃;

[0059] Add H2O2 to the detection system (1 mL) to make the concentration of H2O2 in the system 400 µM;

[0060] Detection time: 5 minutes.

[0061] The results are as follows Figure 1 And Table 2.

[0062] Table 2 Temperature Test Grouping

[0063]

[0064] At 40℃, LPMO catalyzed the oxidation of 2,6-DMP at a rate of 0.188 within 0-3 min, and the rate dropped to 0.123 within 3-5 min, a decrease of 35%, indicating that a single high concentration of H2O2 caused oxidative damage to the activity of LPMO.

[0065] At 50℃, the initial rate of LPMO (0.205) increased by 9% compared to 40℃, indicating that heating helps to improve catalytic efficiency; however, the rate dropped sharply to 0.005 (a decrease of 98%) within 3-5 min, and product accumulation basically stopped, indicating that the higher temperature accelerated the oxidative damage of H2O2 to the copper active site of LPMO, causing irreversible inactivation of the enzyme in a short time.

[0066] Although LPMO exhibits high initial catalytic activity at 50 °C, its deactivation rate is significantly accelerated in the presence of a single high concentration of H2O2. This result indicates that to utilize the catalytic function of LPMO at refining temperatures of 50-60 °C, a slow-release H2O2 supply strategy must be adopted to maintain a low-concentration steady-state H2O2 and avoid rapid oxidative damage to the enzyme's active site.

[0067] Example 3:

[0068] This embodiment verifies the protective effect of in-situ sustained release of H2O2 from glucose oxidase on LPMO activity, as detailed below.

[0069] Prepare the detection system (1 mL): 0.2 U / ml LPMO (AA9 family, 90 U / g), 3 mM 2,6-DMP, and the remainder is buffer solution.

[0070] Buffer solution: 100 mM phosphate buffer, pH 7.0;

[0071] Temperature: 50℃;

[0072] Detection time: 10 minutes.

[0073] The results are as follows Figure 2 As shown in Table 3.

[0074] Table 3 H2O2 Supply Method Experiment Groups

[0075]

[0076] After a single addition of H2O2, the catalytic rate of LPMO dropped sharply (77%) after 3 minutes, indicating irreversible oxidative damage to the active site. Stepwise addition improved the situation somewhat, but the rate still decreased by 54%. In contrast, the rate decrease in the GOx in-situ sustained-release group was only 10%, and the product accumulation was 131% and 56% higher than that of control groups A and B, respectively. This demonstrates that continuous in-situ supply of H2O2 to glucose oxidase is the optimal way to maintain the long-term catalytic activity of LPMO.

[0077] Example 4:

[0078] This embodiment studies the difference in refining effect between a two-stage pH process and a single pH process.

[0079] Experimental group: Prepare the treatment solution of Example 1, pH 6.8, and add it to pure cotton knitted fabric at a bath ratio of 1:20; heat to 55℃ and oxidize for 30 minutes; slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes) and hydrolyze for 40 minutes; heat to 85℃ to inactivate enzymes, and wash the fabric with water until neutral.

[0080] Control group 1: Prepare the treatment solution of Example 1, pH 8.0, and add it to pure cotton knitted fabric at a bath ratio of 1:20; heat to 60°C for 75 minutes, heat to 85°C to inactivate enzymes, and wash the fabric with water until neutral.

[0081] Control group 2: Prepare the treatment solution of Example 1, pH 7.0, and add it to pure cotton knitted fabric at a bath ratio of 1:20; heat to 60℃ for 75 minutes, heat to 85℃ to inactivate enzymes, and wash the fabric with water until neutral.

[0082] Table 4 Test results for different processes

[0083]

[0084] Table 4 shows that at a constant pH of 8.0, pectinase activity is high, but LPMO is severely inactivated, resulting in significant cottonseed hull residue. At a constant pH of 7.0, LPMO is stable, but pectinase activity is insufficient, leading to unsatisfactory capillary effect and pectin removal. The two-stage process of this invention balances the preservation of the activity of both enzymes, effectively solving the technical problem of pH incompatibility between LPMO and alkaline pectinase.

[0085] Example 5:

[0086] This embodiment verifies the synergistic effect among the oxidized LPMO, laccase, and GOx.

[0087] Prepare the treatment solution, which includes 3 g / L of compound enzyme preparation, 2 g / L of Tween-80, 2 g / L of osmotic agent JFC, 1 mM glucose, and the balance being water, and adjust the pH to 6.8.

[0088] Experimental Group 1: Prepare the above treatment solution, in which the compound enzyme preparation includes 50 parts pectinase, 15 parts xylanase, and 5 parts cellulase; add pure cotton knitted fabric at a bath ratio of 1:20; heat to 55℃ and oxidize for 30 minutes; slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes; heat to 85℃ to inactivate the enzyme, and wash the fabric until neutral.

[0089] Experimental Group 2: Prepare the above treatment solution, in which the compound enzyme preparation includes 25 parts LPMO, 50 parts pectinase, 15 parts xylanase, and 5 parts cellulase; add pure cotton knitted fabric at a bath ratio of 1:20; heat to 55℃ and oxidize for 30 minutes; slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes; heat to 85℃ to inactivate the enzyme, and wash the fabric until neutral.

[0090] Experimental Group 3: Prepare the above treatment solution, in which the compound enzyme preparation includes 25 parts laccase, 50 parts pectinase, 15 parts xylanase, and 5 parts cellulase; add pure cotton knitted fabric at a bath ratio of 1:20; heat to 55℃ and oxidize for 30 minutes; slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes; heat to 85℃ to inactivate the enzyme, and wash the fabric until neutral.

[0091] Experimental Group 4: Prepare the above treatment solution, in which the compound enzyme preparation includes 20 parts LPMO, 5 parts GOx, 50 parts pectinase, 15 parts xylanase, and 5 parts cellulase; add pure cotton knitted fabric at a bath ratio of 1:20; heat to 55℃ and oxidize for 30 minutes; slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes; heat to 85℃ to inactivate the enzyme, and wash the fabric until neutral.

[0092] Experimental Group 5: Prepare the above treatment solution, in which the compound enzyme preparation includes 5 parts GOx, 20 parts laccase, 50 parts pectinase, 15 parts xylanase, and 5 parts cellulase; add pure cotton knitted fabric at a bath ratio of 1:20; heat to 55℃ and oxidize for 30 minutes; slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes; heat to 85℃ to inactivate the enzyme, and wash the fabric until neutral.

[0093] Experimental Group 6: Prepare the above treatment solution, in which the compound enzyme preparation includes 10 parts LPMO, 5 parts GOx, 10 parts laccase, 50 parts pectinase, 15 parts xylanase, and 5 parts cellulase; add pure cotton knitted fabric at a bath ratio of 1:20; heat to 55℃ and oxidize for 30 minutes; slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes; heat to 85℃ to inactivate the enzyme, and wash the fabric until neutral.

[0094] Table 5. Enzymatic hydrolysis effects of different oxidation stages

[0095]

[0096] Table 5 shows that the removal efficiency of cottonseed hulls was worst when only the hydrolysis stage (without the oxidation stage) was present, indicating that the oxidation stage is indispensable for opening the interface of cottonseed hulls. The effect of LPMO or laccase alone combined with GOx was limited, but the effect was significantly enhanced when both were present (experimental group 6), confirming the synergistic mechanism of electron donation by laccase and oxidation by LPMO. The participation of GOx further improved the effect, indicating that a stable supply of H2O2 is crucial for the function of LPMO.

[0097] Example 6:

[0098] This embodiment verifies the optimal ratio of LPMO to laccase in the oxidation phase.

[0099] Multiple treatment solutions were prepared, each containing 3 g / L of a compound enzyme preparation, 2 g / L of Tween-80, 2 g / L of JFC permeabilizer, 1 mM glucose, and the remainder being water, adjusted to pH 6.8. The compound enzyme preparation consisted of 50 parts pectinase, 15 parts xylanase, 5 parts cellulase, 5 parts GOx, and a total of 20 parts LPMO and laccase, with varying ratios of LPMO and laccase in each group.

[0100] The low-temperature refining method of fabric in Example 1 and the above-mentioned treatment solution were used to treat pure cotton knitted fabrics, and the results are shown in Table 6.

[0101] Table 6. Effect of different LPMO / laccase ratios on cottonseed hull removal efficiency.

[0102]

[0103] Table 6 shows that the LPMO:laccase ratio of 8:12 resulted in the optimal removal of cottonseed hulls; deviations from this ratio decreased the effectiveness. At a ratio of 8:12 (approximately a 1:1.5 molar activity ratio), the phenolic electron donors released by laccase reached a dynamic equilibrium with the consumption of LPMO, satisfying the reduction requirements of LPMO without causing interference from excessive phenolic accumulation. This result confirms a redox synergistic effect between LPMO and laccase.

[0104] Example 8:

[0105] This embodiment provides a compound enzyme preparation for low-temperature refining of fabrics, comprising, by weight: 12 parts of LPMO (AA9 family, 90 U / g); 18 parts of laccase (1000 U / mL); 6 parts of glucose oxidase (5000 U / mL); 40 parts of alkaline pectinase (1000 U / mL); 20 parts of xylanase (10000 U / mL); and 4 parts of cellulase (5000 U / mL).

[0106] Based on the above-mentioned compound enzyme preparation, this embodiment also provides a low-temperature refining treatment solution for fabrics, comprising 3 g / L compound enzyme preparation, 2 g / L Tween-80, 2 g / L penetrant JFC, 1 mM glucose, and the remainder being water.

[0107] Based on the above-mentioned processing liquid, this embodiment also provides a method for low-temperature refining of fabrics, including the following steps:

[0108] Prepare the above treatment solution with pH 6.8 and add it to the modal knitted fabric at a bath ratio of 1:20;

[0109] Heat to 55℃ and allow the oxidation reaction to proceed for 30 minutes.

[0110] Slowly add Na2CO3 to the reaction system to adjust the pH to 8.0, heat to 60℃ (5 minutes), and hydrolyze for 40 minutes;

[0111] Heat the fabric to 85°C to inactivate the enzymes, then wash it with water until it is neutral.

[0112] The conventional alkali refining method is as follows:

[0113] Alkali: NaOH 20 g / L (or 20% owf)

[0114] Temperature: 98℃

[0115] Processing time: 100 minutes

[0116] Bath ratio: 1:20

[0117] Heat to 95℃, main wash for 100 minutes, then rinse with water (multiple hot water washes with added acid to neutralize).

[0118] The properties of the modal knitted fabric before and after treatment are shown in Table 7.

[0119] Table 7 Results of Modal Knitted Fabric Processing

[0120]

[0121] As shown in Table 7, the compound enzyme preparation, treatment solution and method provided by the present invention are also effective on modal fibers. Moreover, because modal fibers have a looser structure, the enzyme permeability is better, and the treatment time can be shortened to 65-70 minutes compared with conventional alkali treatment.

[0122] Example 9:

[0123] This embodiment uses a 100kg capacity ambient temperature and pressure dyeing machine. Based on the compound enzyme preparation, treatment solution, and refining method of Example 1, 100kg of pure cotton knitted fabric is refined. The results are shown in Table 8. The conventional alkali refining method is the same as in Example 8.

[0124] Table 8 Results of large-scale refining of pure cotton knitted fabrics

[0125]

[0126] The results of the 100kg scale-up test show that the two-stage compound enzyme scouring process can operate stably on an industrial scale. The quality of the treated fabric reaches the level of alkali scouring, and COD emissions are reduced by more than 60%, which meets the requirements of clean production.

[0127] Example 10:

[0128] This embodiment verifies the appropriate concentration range of glucose added to the treatment solution.

[0129] Based on the treatment solution formulation of Example 1, multiple treatment solutions were prepared, differing only in the concentration of glucose added in each group. Pure cotton knitted fabric was treated with each treatment solution using the refining method of Example 1, and the results are shown in Table 9.

[0130] Table 9. Effect of glucose concentration in the treatment solution on the refining process.

[0131]

[0132] Without glucose, GOx cannot produce H2O2, LPMO lacks a co-substrate, and the removal of cottonseed hulls is poor. When glucose is 0.5-1.0 mM, the steady-state concentration of H2O2 is maintained at 1-6 µM, matching the Km value of LPMO, resulting in optimal refining. When glucose is ≥2.0 mM, the H2O2 generation rate is too fast, the steady-state concentration increases, LPMO activity decreases significantly, and the refining effect is reduced. The suitable concentration of glucose added to the treatment solution is 0.5-2.0 mM, preferably 0.5-1.0 mM.

[0133] The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. All designs that are the same as or similar to the present invention are within the scope of protection of the present invention.

Claims

1. A compound enzyme preparation for low-temperature refining of fabrics, characterized in that: This includes polysaccharide cleavage monooxygenase, laccase, glucose oxidase, pectinase, and xylanase.

2. The composite enzyme preparation for low-temperature refining of fabrics as described in claim 1, characterized in that: By weight fraction, the compound enzyme preparation comprises 1-20 parts polysaccharide lysing monooxygenase, 5-25 parts laccase, 1-10 parts glucose oxidase, 30-70 parts pectinase, 5-20 parts xylanase, and 0-10 parts cellulase.

3. The composite enzyme preparation for low-temperature refining of fabrics as described in claim 2, characterized in that: By weight fraction, the compound enzyme preparation comprises 5-10 parts polysaccharide lysing monooxygenase, 10-15 parts laccase, 3-6 parts glucose oxidase, 40-60 parts pectinase, 5-15 parts xylanase, and 1-5 parts cellulase.

4. The compound enzyme preparation for low-temperature refining of materials as described in claim 2, characterized in that: The compound enzyme preparation contains polysaccharide cleavage monooxygenase with an activity of 70-90 U / g, laccase with an activity of 500-5000 U / g, glucose oxidase with an activity of 1000-10000 U / g, pectinase with an activity of 300-2000 U / mL, xylanase with an activity of 5000-100000 U / g, and cellulase with an activity of 2000-200000 U / mL.

5. A low-temperature refining solution for fabrics, characterized in that: It includes nonionic surfactants, penetrants, glucose, water, and the complex enzyme preparation described in any one of claims 1-4.

6. The fabric low-temperature refining solution as described in claim 5, characterized in that: Each liter of the fabric low-temperature refining solution comprises 2-4 g / L of compound enzyme preparation, 2-4 g / L of nonionic surfactant, and 0.5-2 mM glucose.

7. The fabric low-temperature refining solution as described in claim 5, characterized in that: The pH of the low-temperature refining solution for the fabric is 6.5-7.

0.

8. A method for low-temperature refining of fabrics, characterized in that, Includes the following steps: Prepare the treatment solution according to any one of claims 5-7; immerse the fabric to be treated in the treatment solution and heat it to carry out an oxidation reaction; add alkali solution to the reaction system to adjust the pH to 8.0-8.5, and heat it to carry out a hydrolysis reaction. Inactivate the enzymes and wash the fabric until it is neutral.

9. The low-temperature refining method for fabrics as described in claim 8, characterized in that: The ratio of the fabric to be treated to the treatment solution is 1:10-30.

10. The low-temperature refining method for fabrics as described in claim 8, characterized in that: The oxidation reaction conditions are: heating to 50-55℃ and reacting for 30-35 minutes; the hydrolysis reaction conditions are: heating to 60-65℃ and reacting for 35-40 minutes.

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