High-purity crocin extraction and separation method and application thereof

Abstract

The invention provides a high-purity crocin extraction and separation method and application thereof, and relates to the field of industrial dyestuff, the high-purity crocin extraction and separation method comprises the following steps: S1, raw material preparation, S2, device preparation, S3, crude extraction for later use, S4, preliminary purification and S5, advanced purification. The industrial dye is prepared from the following components in parts by weight: 0.3 to 0.7 part of high-purity crocin, 3 to 6 parts of ethanol, 0.1 to 0.3 part of citric acid, 3 to 5 parts of urea, 5 to 7 parts of table salt, 0.03 to 0.06 part of vitamin C, 0.04 to 0.07 part of sodium benzoate, 1.2 to 1.5 parts of natural plant color fixing agent, 1.2 to 1.5 parts of bio-based color fixing agent and the balance of deionized water. By using a multi-stage dynamic countercurrent ultrasonic extraction technology, crocin in a crushed gardenia raw material can be efficiently extracted, the concentration difference between a solvent and the raw material is gradually increased, the extraction efficiency is improved through multi-stage extraction, full contact of the solvent and the raw material is ensured, the extraction efficiency is improved through dynamic stirring, and plant cell walls are destroyed; ultrasonic-assisted acceleration of release of effective components is realized, and extraction efficiency is improved.

Description

Technical Field

[0001] The invention relates to the field of industrial dyes, and in particular to a method for extracting and separating high-purity crocin and application thereof. Background Art

[0002] Gardenia contains rich crocin, which is a natural pigment with multiple pharmacological activities and broad application prospects. However, traditional extraction methods often have problems such as low extraction efficiency, high solvent consumption, and environmental pollution. Therefore, it is particularly important to develop efficient and environmentally friendly extraction technology. In the extraction process, how to improve the concentration of crocin crude extraction solution is an important issue. The crocin content extracted by the traditional preliminary crude extraction solution is low, and the extraction method often requires a large amount of solvent, resulting in a low concentration of the extract, which wastes a certain amount of crocin contained in gardenia, is not conducive to subsequent purification and concentration, and has a low utilization rate of crocin inside the gardenia.

[0003] Natural plant dyes have received extensive attention in the field of textile dyeing due to their environmentally friendly, non-toxic and harmless characteristics. However, natural plant dyes generally have problems such as poor color fixation effect and low color fastness during the dyeing process, which limits their application in industrial production. In order to improve the color fixation effect and fiber protection performance of natural plant dyes, the combined use of natural plant color fixers and bio-based color fixers has been explored, and the application of color fixers in high-purity saffron dyeing has been explored. Although the existing chemical color fixers have brighter colors when used, they contain formaldehyde. For example, formaldehyde resin-type color fixers may release free formaldehyde during production and use, which not only pollutes the environment, but also poses a threat to human health. Long-term use Contact with formaldehyde may cause symptoms such as skin itching, rash, and respiratory inflammation. In severe cases, it may even cause damage to the immune system. For example, cationic polymer-type fixing agents have strong cationic properties and easily react with anionic substances on the skin surface, causing skin irritation and allergic reactions. Especially for people with sensitive skin, clothes treated with these fixing agents may cause skin itching, rash and other symptoms. At the same time, existing chemical fixing agents will also affect clothing fibers. For example, cross-linking reaction fixing agents may cause fiber hardening while improving color fastness, affecting the feel and softness of the fabric and reducing wrinkle resistance. Fiber hardening may also cause the fabric's wrinkle resistance to decrease, affecting wearing comfort.

[0004] Therefore, it is necessary to provide a new high-purity crocin extraction and separation method and its application to solve the above-mentioned technical problems. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for extracting and separating high-purity crocin and its application.

[0006] The present invention provides a method for extracting and separating high-purity crocin, comprising the following steps:

[0007] S1. Raw material preparation: prepare a certain amount of gardenia raw material and crush the gardenia for later use;

[0008] S2. Device preparation: preparing a multi-stage dynamic countercurrent ultrasonic extraction device for proportioning the crushed gardenia raw material with a coarse material solution;

[0009] S3, crude extraction for standby use, using a multi-stage dynamic countercurrent ultrasonic extraction device to perform crude material extraction on the crushed gardenia raw material to form a crude material solution of crocin for standby use;

[0010] S4, preliminary purification, filtering, centrifuging, and purifying the crude material solution of crocin by activated carbon adsorption to obtain a preliminary pure solution of crocin;

[0011] S5, advanced purification, using solid phase extraction SPE method, high performance liquid chromatography HPLC method and dynamic axial compression column method to collect high purity crocin finished product;

[0012] Preferably, the multi-stage dynamic countercurrent ultrasonic extraction device comprises a plurality of extraction units, and the plurality of extraction units are connected by pipelines to achieve continuous countercurrent flow of solvent and raw material;

[0013] The extraction unit comprises a raw material tank, a solvent tank, a stirrer and an ultrasonic generator.

[0014] Preferably, the specific steps of the multi-stage dynamic countercurrent ultrasonic extraction technology in the step S2 of crude extraction are as follows:

[0015] S101, using the device, using a multi-stage dynamic countercurrent ultrasonic extraction device, loading saffron raw material and 50% ethanol aqueous solution into a raw material tank and a solvent tank respectively;

[0016] S102, multi-stage setting, setting multiple extraction units, each unit is connected by a pipeline to achieve continuous reverse flow of solvent and raw material, so that the discharge port of the first-stage extraction unit is connected to the feed port of the second-stage extraction unit, and so on, to form a multi-stage extraction system;

[0017] S103, ultrasonic setting, turning on the plurality of ultrasonic generators, setting the ultrasonic frequency and power so that the ultrasonic waves are evenly distributed in the entire extraction system, the ultrasonic frequency is set to 20 kHz, and the power is set to 100 W;

[0018] S104, stirring setting, turning on the plurality of stirrers, setting the stirring speed of the stirrers to 50 rpm, to ensure sufficient mixing of the raw materials and the solvent;

[0019] S105, temperature setting, setting the extraction temperature to 40°C and the extraction time to 2 hours;

[0020] S106, collecting the solutions, combining the collected extracts for subsequent processing and analysis.

[0021] Preferably, the specific steps of the preliminary purification in step S4 are as follows:

[0022] S201, filtration, use filter paper or filter to remove large particles of impurities;

[0023] S202, centrifugation, using a centrifuge set at a centrifugal speed of 3000 rpm, running for 15 minutes;

[0024] S203, activated carbon adsorption, add 1% activated carbon, stir for 30 minutes and then filter.

[0025] Preferably, the specific operation steps of the advanced purification in step S5 are as follows:

[0026] S301, ultrafiltration, using ultrafiltration membrane to remove macromolecular impurities;

[0027] S302, macroporous adsorption resin column, adsorption, elution and nanofiltration to obtain the gardenia yellow pigment aqueous solution;

[0028] S303, polyamide resin column, the yellow pigment aqueous solution is adsorbed by the polyamide resin column, eluted, and concentrated by nanofiltration to obtain a crude crocin;

[0029] S304, dynamic axial compression column, preparing the crude crocin into an aqueous solution of 25-33 mg / mL, injecting the solution into the dynamic axial compression column, using 32-37% ethanol aqueous solution as the mobile phase, performing analytical separation to obtain a crocin ethanol solution;

[0030] S305, high performance liquid chromatography, using a C18 chromatographic column, a mobile phase of 70% ethanol in water, a flow rate of 1 mL / min, and a detection wavelength of 440 nm, ultimately obtaining high-purity crocin.

[0031] An application of an industrial dye agent of high-purity crocin, the industrial dye agent comprising the following ingredients: 0.3-0.7 parts of high-purity crocin, 3-6 parts of ethanol, 0.1-0.3 parts of citric acid, 3-5 parts of urea, 5-7 parts of salt, 0.03-0.06 parts of vitamin C and 0.04-0.07 parts of sodium benzoate, and the remaining parts are all deionized water;

[0032] The high-purity crocin is prepared by the above-mentioned high-purity crocin extraction and separation method.

[0033] Preferably, the industrial dye further comprises 1.2-1.5 parts of a natural plant color fixing agent and 1.2-1.5 parts of a bio-based color fixing agent.

[0034] Preferably, the natural plant color fixing agent includes 0.4-0.6 parts of tannic acid, 0.4-0.5 parts of iron alum, and 0.4-0.5 parts of alum.

[0035] Preferably, the bio-based color fixing agent comprises 0.6-0.75 parts of polyethyleneimine and 0.6-0.75 parts of chitosan.

[0036] Compared with the related art, the high-purity crocin extraction and separation method and application provided by the present invention have the following beneficial effects:

[0037] 1. By using multi-stage dynamic countercurrent ultrasonic extraction technology, crocin in the crushed gardenia raw material can be efficiently extracted, wherein the concentration difference between the solvent and the raw material is gradually increased, multi-stage extraction improves the extraction efficiency, ensures full contact between the solvent and the raw material, dynamic stirring improves the extraction efficiency, destroys the plant cell wall, and ultrasonic assistance accelerates the release of the active ingredients, improves the extraction efficiency, and facilitates the subsequent purification and concentration.

[0038] 2. Improve the concentration of the crude crocin solution extracted from the crushed gardenia raw materials to enable efficient extraction, realize continuous countercurrent flow of solvent and raw materials, countercurrent extraction: further improve the extraction efficiency, gradually increase the concentration difference between the solvent and the raw materials, multi-stage extraction to increase the concentration of the extract, increase the penetration capacity of the solvent, and ultrasonic assistance to increase the concentration of the extract, which is convenient for industrial production.

[0039] 3. The combined use of natural plant fixing agents and bio-based fixing agents can significantly improve the fixing effect and fiber protection performance of high-purity crocin dyeing. The combined use group showed the best results in physical properties, chemical properties, microstructure, color fastness and biocompatibility. Through systematic experimental verification and data analysis, the application formula ratio and usage method are optimized to ensure the best dyeing effect and fiber protection effect, while ensuring wearing comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A wireframe diagram of the overall process of a high-purity crocin extraction and separation method provided by the present invention;

[0041] Figure 2 The overall process wireframe diagram of the multi-stage dynamic countercurrent ultrasonic extraction technology provided by the present invention;

[0042] Figure 3 A wireframe diagram of the process of preliminary purification provided by the present invention;

[0043] Figure 4A wireframe diagram of the advanced purification process provided by the present invention. DETAILED DESCRIPTION

[0044] The following is a further description of a high-purity crocin extraction and separation method of the present invention in conjunction with the accompanying drawings, data tables and implementation examples.

[0045] Please refer to Figure 1 , Figure 2 , Figure 3 as well as Figure 4 ,in, Figure 1 A wireframe diagram of the overall process of a high-purity crocin extraction and separation method provided by the present invention; Figure 2 The overall process wireframe diagram of the multi-stage dynamic countercurrent ultrasonic extraction technology provided by the present invention; Figure 3 A wireframe diagram of the process of preliminary purification provided by the present invention; Figure 4 A wireframe diagram of the advanced purification process provided by the present invention.

[0046] The present invention will be further described below in conjunction with the embodiments.

[0047] Embodiment 1:

[0048] In the specific implementation process, Figure 1-Figure 4 As shown, the present invention provides a method for extracting and separating high-purity crocin, and the present invention provides a method for extracting and separating high-purity crocin, which comprises the following steps:

[0049] S1. Raw material preparation: prepare a certain amount of gardenia raw material and crush the gardenia for later use;

[0050] S2. Device preparation: preparing a multi-stage dynamic countercurrent ultrasonic extraction device for proportioning the crushed gardenia raw material with a coarse material solution;

[0051] It should be noted that the multi-stage dynamic countercurrent ultrasonic extraction device integrates multi-stage extraction, dynamic stirring, ultrasonic assistance and countercurrent extraction technology to form a new multi-stage dynamic countercurrent ultrasonic extraction technology. Secondly, the device technology can significantly improve the extraction efficiency, solution concentration and production efficiency, while reducing costs. This new extraction method is suitable for large-scale industrial production and has broad application prospects. Multi-stage dynamic countercurrent ultrasonic extraction technology has obvious advantages in extraction efficiency, solution concentration, ease of operation and cost control, and is an important development direction for future extraction technology.

[0052] S3, crude extraction for standby use, using a multi-stage dynamic countercurrent ultrasonic extraction device to perform crude material extraction on the crushed gardenia raw material to form a crude material solution of crocin for standby use;

[0053] S4, preliminary purification, filtering, centrifuging, and purifying the crude material solution of crocin by activated carbon adsorption to obtain a preliminary pure solution of crocin;

[0054] S5, advanced purification, the primary pure solution of crocin is subjected to solid phase extraction (SPE) method, high performance liquid chromatography (HPLC) method and dynamic axial compression column method to collect the high-purity crocin finished product.

[0055] The multi-stage dynamic countercurrent ultrasonic extraction device includes a plurality of extraction units, and the plurality of extraction units are connected by pipelines to realize continuous countercurrent flow of solvent and raw material;

[0056] The extraction unit includes a raw material tank, a solvent tank, a stirrer and an ultrasonic generator.

[0057] The specific steps of the multi-stage dynamic countercurrent ultrasonic extraction technology in step S2 crude extraction are as follows:

[0058] S101, using the device, using a multi-stage dynamic countercurrent ultrasonic extraction device, loading saffron raw material and 50% ethanol aqueous solution into a raw material tank and a solvent tank respectively;

[0059] S102, multi-stage setting, setting multiple extraction units, each unit is connected by a pipeline to achieve continuous reverse flow of solvent and raw material, so that the discharge port of the first-stage extraction unit is connected to the feed port of the second-stage extraction unit, and so on, to form a multi-stage extraction system;

[0060] S103, ultrasonic setting, turning on multiple ultrasonic generators, setting the ultrasonic frequency and power so that the ultrasonic waves are evenly distributed in the entire extraction system, the ultrasonic frequency is set to 20 kHz, and the power is set to 100 W;

[0061] S104, stirring setting, turning on multiple stirrers, setting the stirring speed of the stirrers to 50 rpm, to ensure sufficient mixing of the raw materials and the solvent;

[0062] S105, temperature setting, setting the extraction temperature to 40°C and the extraction time to 2 hours;

[0063] S106, collecting the solutions, combining the collected extracts to form a crude solution for subsequent processing and analysis.

[0064] The specific steps of step S4 preliminary purification are as follows:

[0065] S201, filtration, use filter paper or filter to remove large particles of impurities;

[0066] S202, centrifugation, using a centrifuge set at a centrifugal speed of 3000 rpm, running for 15 minutes;

[0067] S203, activated carbon adsorption, add 1% activated carbon, stir for 30 minutes and then filter.

[0068] The specific operation steps of step S5 advanced purification are as follows:

[0069] S301, ultrafiltration, using ultrafiltration membrane to remove macromolecular impurities;

[0070] S302, macroporous adsorption resin column, adsorption, elution and nanofiltration to obtain the gardenia yellow pigment aqueous solution;

[0071] S303, polyamide resin column, the yellow pigment aqueous solution is adsorbed by the polyamide resin column, eluted, and concentrated by nanofiltration to obtain a crude crocin;

[0072] S304, dynamic axial compression column, preparing the crude crocin into an aqueous solution of 25-33 mg / mL, injecting the solution into the dynamic axial compression column, using 32-37% ethanol aqueous solution as the mobile phase, performing analytical separation to obtain a crocin ethanol solution;

[0073] S305, high performance liquid chromatography, using a C18 chromatographic column, a mobile phase of 70% ethanol in water, a flow rate of 1 mL / min, and a detection wavelength of 440 nm, ultimately obtaining high-purity crocin.

[0074] Comparative Example 1:

[0075] In the specific implementation process, the difference from the first embodiment is that:

[0076] The extraction technology used in step S2 for crude extraction is multi-stage extraction, and the specific steps of multi-stage extraction are as follows:

[0077] Step 1: Initial extraction: Mix the crushed gardenia raw material with 50% ethanol aqueous solution in a ratio of 1:10 (w / v), soak at room temperature for 24 hours, and stir every 6 hours.

[0078] Step 2: Filtration: Filter the extract and retain the filtrate.

[0079] Step 3: Re-extraction: Mix the filter residue with 50% ethanol aqueous solution at a ratio of 1:10 (w / v) and repeat the above step 2.

[0080] Step 4: Collection: Collect the filtrates from multiple extractions and combine them for later use.

[0081] Comparative Example 2:

[0082] In the specific implementation process, the difference from the first embodiment is that:

[0083] The extraction technology used in step S2 for crude extraction is countercurrent extraction, and the specific steps of countercurrent extraction are as follows:

[0084] Step 1, device: using a countercurrent extraction device, the crushed gardenia raw material and 50% ethanol aqueous solution are respectively loaded into a raw material tank and a solvent tank;

[0085] Step 2, conditions: set the extraction temperature to 40°C and the extraction time to 2 hours;

[0086] Step 3, collection: After the countercurrent extraction is completed, the extract is collected.

[0087] Experimental Group 1:

[0088] The three crude material solution extraction methods of Example 1, Comparative Example 1 and Comparative Example 2 were respectively adopted, and 50 grams of crushed Gardenia raw material was added to perform extraction tests, and the experimental results were recorded;

[0089] The results of the specific experimental group 1 are shown in Table 1:

[0090] index Embodiment 1 Implementation of Comparative Example 1 Implementation of Comparative Example 2 purity(%) 96 81 87 Extraction efficiency (%) 92 73 81 Impurity content (%) 4 19 13 Extraction time (hours) 2 24 2 Difficulty of operation Simpler Simple Simpler

[0091] Table 1

[0092] From the analysis of Table 1, it can be seen that when using Example 1, Comparative Example 1 and Comparative Example 2, Example 1 adopts a multi-stage dynamic countercurrent ultrasonic extraction device and an advanced purification method, which can efficiently extract high-purity crocin, and the purity and extraction efficiency are better than those of Comparative Example 1 and Comparative Example 2. Although Comparative Example 1 is simple to operate, its extraction efficiency and purity are low, and its impurity content is high. Although Comparative Example 2 has a shorter extraction time, its purity and extraction efficiency are slightly lower than those of Example 1. Therefore, the method of Example 1 has obvious advantages in extracting crude crocin solution.

[0093] The application of the industrial dye of high-purity crocin of the present invention is further described below in conjunction with the accompanying drawings, data tables and implementation methods.

[0094] The present invention will be further described below in conjunction with the embodiments.

[0095] Embodiment 2:

[0096] An application of an industrial dye agent of high-purity crocin, the industrial dye agent comprising the following components: 0.3-0.7 parts of high-purity crocin, 3-6 parts of ethanol, 0.1-0.3 parts of citric acid, 3-5 parts of urea, 5-7 parts of salt, 0.03-0.06 parts of vitamin C and 0.04-0.07 parts of sodium benzoate, and the remaining parts are all deionized water;

[0097] The high-purity crocin is prepared by the above-mentioned high-purity crocin extraction and separation method.

[0098] The industrial dye also includes 1.2-1.5 parts of natural plant fixing agent and 1.2-1.5 parts of bio-based fixing agent.

[0099] The natural plant color fixing agent includes 0.4-0.6 parts of tannic acid, 0.4-0.5 parts of iron alum and 0.4-0.5 parts of alum.

[0100] The bio-based color fixing agent comprises 0.6-0.75 parts of polyethyleneimine and 0.6-0.75 parts of chitosan.

[0101] It should be noted that the specific use steps of industrial dyes are as follows:

[0102] Operation 1. Dissolve crocin: Add 0.5 parts of high-purity crocin to 93.5 parts of deionized water and stir until completely dissolved;

[0103] Operation 2, add ethanol: add 5 parts of ethanol and continue to stir evenly to improve the permeability and adhesion of the dye;

[0104] Operation 3: Adjust the pH value: Add 0.2 parts of citric acid to adjust the pH value of the dye solution to between 5.0 and 6.0 to ensure the stability of the dye and the dyeing effect;

[0105] Operation 4: Add dyeing aids: Add 3 parts of urea and 7 parts of salt respectively, stir thoroughly until completely dissolved to improve the uniformity and depth of dyeing;

[0106] Operation 5: Add color fixative: Add 1 part of natural plant color fixative and 1 part of bio-based color fixative, stir thoroughly until completely dissolved to improve the color fixation effect of the dye on the fiber;

[0107] Operation 6. Filtration: Use filter paper or filter to filter the dye solution to remove possible insoluble impurities and ensure the purity of the dye solution;

[0108] Operation 7, dyeing: immerse the fabric to be dyed in the dye solution, control the temperature at about 70°C, and soak for 30-60 minutes;

[0109] Operation 8: Fixation treatment: put the dyed fabric into a solution containing a fixing agent, control the temperature at 40-50°C, and soak for 20-30 minutes;

[0110] Operation 9. Cleaning: After soaking, rinse thoroughly with clean water to remove excess fixing agent;

[0111] Operation 10: Drying: Air dry or tumble dry the treated fabric to ensure even drying.

[0112] Comparative Example 3:

[0113] In the specific implementation process, the difference from Experimental Example 2 is that:

[0114] The industrial dye comprises the following ingredients: 0.3-0.7 parts of high-purity crocin, 3-6 parts of ethanol, 0.1-0.3 parts of citric acid, 3-5 parts of urea, 5-7 parts of salt, 0.03-0.06 parts of vitamin C and 0.04-0.07 parts of sodium benzoate, and the remaining parts are deionized water;

[0115] The industrial dye also includes 1.2-1.5 parts of natural plant fixing agent;

[0116] The natural plant color fixing agent includes 0.4-0.6 parts of tannic acid, 0.4-0.5 parts of iron alum and 0.4-0.5 parts of alum.

[0117] Comparative Example 4:

[0118] In the specific implementation process, the differences from Experimental Example 2 are as follows:

[0119] The industrial dye comprises the following ingredients: 0.3-0.7 parts of high-purity crocin, 3-6 parts of ethanol, 0.1-0.3 parts of citric acid, 3-5 parts of urea, 5-7 parts of salt, 0.03-0.06 parts of vitamin C and 0.04-0.07 parts of sodium benzoate, and the remaining parts are all deionized water.

[0120] The industrial dye agent also includes 1.2-1.5 parts of a bio-based color fixing agent;

[0121] The bio-based color fixing agent comprises 0.6-0.75 parts of polyethyleneimine and 0.6-0.75 parts of chitosan.

[0122] Comparative Example 5:

[0123] In the specific implementation process, the differences from Experimental Example 2 are as follows:

[0124] The industrial dye comprises the following ingredients: 0.3-0.7 parts of high-purity crocin, 3-6 parts of ethanol, 0.1-0.3 parts of citric acid, 3-5 parts of urea, 5-7 parts of salt, 0.03-0.06 parts of vitamin C and 0.04-0.07 parts of sodium benzoate, and the remaining parts are all deionized water.

[0125] Experimental Group 2

[0126] Example 2, Comparative Example 3, Comparative Example 4 and Comparative Example 5 were selected to form a comparative combination method. These four comparative combinations all added equal amounts of 4 grams of high-purity crocin, 50 grams of ethanol, 2 grams of citric acid, 40 grams of urea, 60 grams of salt, 0.5 grams of vitamin C, 0.5 grams of sodium benzoate and 843 grams of deionized water. After the solvent method of Example 2, Comparative Example 3, Comparative Example 4 and Comparative Example 5 was used for the experiment, 5 grams of tannic acid, 5 grams of iron alum, 5 grams of alum, 0.7 grams of polyethyleneimine and 0.7 grams of chitosan were added to Example 2, 5 grams of tannic acid, 5 grams of iron alum and 5 grams of alum were added to Comparative Example 3, and 0.7 grams of polyethyleneimine and 0.7 grams of chitosan were added to Comparative Example 4.

[0127] Record the experimental calculation results;

[0128] The results of the specific experimental group 2 are shown in the following table:

[0129] The physical properties test results are shown in Table 2:

[0130] Group Embodiment 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Breaking strength(N) 140 120 130 100 Elongation(%) 20 15 18 12 Hardness(Shore A) 40 50 45 55 Feel rating (1-10) 9 7 8 6 Air permeability (L / m²·s) 24 20 22 18 Moisture permeability (g / m²·24h) 2400 2000 2200 1800

[0131] Table 2

[0132] The chemical performance test results are shown in Table 3:

[0133] Group Embodiment 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 pH 6.7 6.5 6.8 7.0 Dye Residue(%) 5 10 8 15

[0134] Table 3

[0135] The results of microstructure analysis are shown in Table 4:

[0136] Group Embodiment 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 SEM observation Very smooth surface Smooth surface Smooth surface Rough surface TEM observation High crystallinity High crystallinity Medium crystallinity Low crystallinity AFM observation Very good smoothness Good smoothness Medium smoothness Poor smoothness

[0137] Table 4

[0138] The color fastness test results are shown in Table 5:

[0139] Group Embodiment 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Washing fastness (grade) 5 4 4 2 Rubbing fastness (grade) 4 3 3 2 Light fastness (grade) 5 4 4 3

[0140] Table 5

[0141] The color fastness test results are shown in Table 6

[0142] Group Embodiment 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Skin irritation rating (1-10) 1 2 2 4 Cytotoxicity score (1-10) 2 3 3 5

[0143] Table 6

[0144] Analysis of Table 2, Table 3, Table 4, Table 5 and Table 6 shows that the physical properties of Example 2, Comparative Example 3, Comparative Example 4 and Comparative Example 5 are as follows: the breaking strength, elongation, air permeability and moisture permeability of Example 2 (combined use of natural plant color fixing agent and bio-based color fixing agent) are better than those of other groups, and the hardness and feel are also the best;

[0145] Chemical properties: The pH value of Example 2 is close to neutral, and the residual dye is the lowest, indicating the best color fixation effect;

[0146] Microstructure: The fiber surface of Example 2 is the smoothest, with the highest crystallinity and the best smoothness;

[0147] Color fastness: The washing fastness, rubbing fastness and light fastness of Example 2 are all at the highest level, indicating that the color is the most stable;

[0148] Biocompatibility: Example 2 had the lowest skin irritation and cytotoxicity scores, indicating the best biocompatibility;

[0149] After statistical analysis, ANOVA (analysis of variance) was used to perform statistical analysis on the data of each group. The results showed that Example 2 was significantly better than other groups in all test items (p < 0.05).

[0150] It is concluded that the combined use of natural plant fixing agents and bio-based fixing agents can significantly improve the fixing effect and fiber protection performance of high-purity crocin dyeing. Experimental data show that the combined use group exhibits the best results in physical properties, chemical properties, microstructure, color fastness and biocompatibility. Through systematic experimental verification and data analysis, the formula ratio and usage method can be optimized to ensure the best dyeing effect and fiber protection effect.

[0151] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for extracting and separating high-purity crocin, characterized in that: The steps include: S1. Raw material preparation: prepare a certain amount of gardenia raw material and crush the gardenia for later use; S2. Device preparation: preparing a multi-stage dynamic countercurrent ultrasonic extraction device for proportioning the crushed gardenia raw material with a coarse material solution; S3, crude extraction for standby use, using a multi-stage dynamic countercurrent ultrasonic extraction device to perform crude material extraction on the crushed gardenia raw material to form a crude material solution of crocin for standby use; S4, preliminary purification, filtering, centrifuging, and purifying the crude material solution of crocin by activated carbon adsorption to obtain a preliminary pure solution of crocin; S5, advanced purification, the primary pure solution of crocin is subjected to solid phase extraction (SPE) method, high performance liquid chromatography (HPLC) method and dynamic axial compression column method to collect the high-purity crocin finished product.

2. The method for extracting and separating high-purity crocin according to claim 1, characterized in that: The multi-stage dynamic countercurrent ultrasonic extraction device comprises a plurality of extraction units, and the plurality of extraction units are connected by pipelines to achieve continuous countercurrent flow of solvent and raw material; The extraction unit comprises a raw material tank, a solvent tank, a stirrer and an ultrasonic generator.

3. The method for extracting and separating high-purity crocin according to claim 2, characterized in that: The specific steps of the multi-stage dynamic countercurrent ultrasonic extraction technology in step S2 for rough extraction are as follows: S101, using the device, using a multi-stage dynamic countercurrent ultrasonic extraction device, loading saffron raw material and 50% ethanol aqueous solution into a raw material tank and a solvent tank respectively; S102, multi-stage setting, setting multiple extraction units, each unit is connected by a pipeline to achieve continuous reverse flow of solvent and raw material, so that the discharge port of the first-stage extraction unit is connected to the feed port of the second-stage extraction unit, and so on, to form a multi-stage extraction system; S103, ultrasonic setting, turning on the plurality of ultrasonic generators, setting the ultrasonic frequency and power so that the ultrasonic waves are evenly distributed in the entire extraction system, the ultrasonic frequency is set to 20 kHz, and the power is set to 100 W; S104, stirring setting, turning on the plurality of stirrers, setting the stirring speed of the stirrers to 50 rpm, to ensure sufficient mixing of the raw materials and the solvent; S105, temperature setting, setting the extraction temperature to 40°C and the extraction time to 2 hours; S106, collecting the solutions, combining the collected extracts for subsequent processing and analysis.

4. The method for extracting and separating high-purity crocin according to claim 3, characterized in that: The specific steps of the preliminary purification in step S4 are as follows: S201, filtration, use filter paper or filter to remove large particles of impurities; S202, centrifugation, using a centrifuge set at a centrifugal speed of 3000 rpm, running for 15 minutes; S203, activated carbon adsorption, add 1% activated carbon, stir for 30 minutes and then filter.

5. The method for extracting and separating high-purity crocin according to claim 4, characterized in that: The specific operation steps of step S5 advanced purification are as follows: S301, ultrafiltration, using ultrafiltration membrane to remove macromolecular impurities; S302, macroporous adsorption resin column, adsorption, elution and nanofiltration to obtain the gardenia yellow pigment aqueous solution; S303, polyamide resin column, the yellow pigment aqueous solution is adsorbed by the polyamide resin column, eluted, and concentrated by nanofiltration to obtain a crude crocin; S304, dynamic axial compression column, preparing the crude crocin into an aqueous solution of 25-33 mg / mL, injecting the solution into the dynamic axial compression column, using 32-37% ethanol aqueous solution as the mobile phase, performing analytical separation to obtain a crocin ethanol solution; S305, high performance liquid chromatography, using a C18 chromatographic column, a mobile phase of 70% ethanol in water, a flow rate of 1 mL / min, and a detection wavelength of 440 nm, ultimately obtaining high-purity crocin.

6. An application of an industrial dye of high-purity crocin, characterized in that: The industrial dye comprises the following ingredients: 0.3-0.7 parts of high-purity crocin, 3-6 parts of ethanol, 0.1-0.3 parts of citric acid, 3-5 parts of urea, 5-7 parts of salt, 0.03-0.06 parts of vitamin C and 0.04-0.07 parts of sodium benzoate, and the remaining parts are deionized water; The high-purity crocin is prepared by the high-purity crocin extraction and separation method described in any one of claims 1-5.

7. The use of the industrial dye of high-purity crocin according to claim 6, characterized in that: The industrial dye further comprises 1.2-1.5 parts of a natural plant color fixing agent and 1.2-1.5 parts of a bio-based color fixing agent.

8. The use of the industrial dye of high-purity crocin according to claim 7, characterized in that: The natural plant color fixing agent comprises 0.4-0.6 parts of tannic acid, 0.4-0.5 parts of iron alum and 0.4-0.5 parts of alum.

9. The use of the industrial dye of high-purity crocin according to claim 8, characterized in that: The bio-based color fixing agent comprises 0.6-0.75 parts of polyethyleneimine and 0.6-0.75 parts of chitosan.

Images