Brassica rapa L. powder and brassica rapa L. residue hydrogel as well as preparation method and application thereof

Abstract

The invention relates to the technical field of biological nanomaterials, in particular to common turnip and common turnip residue hydrogel as well as a preparation method and application thereof, and the preparation method comprises the following steps: freeze-drying and grinding common turnip slices to obtain common turnip powder, mixing the common turnip powder with water, carrying out ultrasonic treatment and vacuum filtration, and freeze-drying filter residues to obtain common turnip residues; adding sodium alginate powder into the heated water bath to obtain a sodium alginate solution, and after sodium alginate is completely dissolved into homogeneous liquid, adding gelatin to obtain a sodium alginate-gelatin mixed system; after gelatin in the sodium alginate-gelatin mixed system is completely dissolved, cooling, respectively adding the common turnip powder and the common turnip residues into the sodium alginate-gelatin mixed system, and mixing to obtain a common turnip powder and common turnip residue hydrogel precursor; a Ca < 2 + > solution is added into the common turnip powder and the common turnip residue hydrogel precursor until the common turnip powder and the common turnip residue hydrogel precursor are colloidal, and the common turnip powder and the common turnip residue hydrogel are obtained, a traditional cross-linking agent is not used in the preparation method of the common turnip residue hydrogel, and chemical pollution and potential health risks are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of biological nanomaterials, and in particular to genus quahog powder and genus quahog residue hydrogel, and a preparation method and application thereof. Background Art

[0002] Plastic is a synthetic polymer compound formed by connecting monomers through polymerization or polycondensation using organic molecules as monomers. Plastics are widely used in many areas of daily life because of their stability, low cost and easy processing. After microplastics discharged into the environment enter the soil, they will migrate and accumulate under the action of plants and organisms. However, catalysts, initiators, plasticizers, colorants, etc. are added during the production of plastics, which will increase the risk of exposure to poisons during the production process and cause heavy metal pollution in the soil. In addition, studies have shown that microplastic particles can affect the transfer of water and nutrients in the contaminated soil, and soil organisms such as earthworms will have obvious growth inhibition after being exposed to high concentrations of PE microplastics. In addition, due to the characteristics of microplastics that they are not easy to degrade, small particles, and easy to absorb, microplastics are very easy to enter the food chain, ingested through food and enriched in the human body. Although the toxicological hazards of microplastic particles to the human body are still in their infancy, it is urgent to pay attention to the environmental and health problems caused by microplastics.

[0003] Compared with plastic food packaging materials, hydrogels have good biocompatibility and have been a hot topic in biomedical research since the 1940s. Hydrogel refers to a hydrophilic three-dimensional mesh gel structure that can swell and absorb water in water to maintain its volume without dissolving. Whether in daily necessities, industrial and agricultural materials, or in the field of medicine and food, hydrogels are often widely used. However, in order to meet the application needs of hydrogels, the current common traditional hydrogel preparation method often introduces cross-linking agents to increase the mechanical strength of the resulting product through polymerization reactions. This cross-linking mechanism inevitably introduces chemical pollution, which in turn brings potential health risks. Summary of the invention

[0004] In view of the deficiencies of the above-mentioned prior art, the object of the present invention is to provide a hydrogel of genus corydalis powder and genus corydalis residue and a preparation method and application thereof. The present invention uses genus corydalis powder and genus corydalis residue as raw materials and utilizes the sodium alginate-calcium chloride method to prepare a new type of antioxidant hydrogel, which is used as a substitute for plastic food packaging materials, while avoiding chemical pollution and potential health risks in traditional hydrogel preparation methods.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A method for preparing genus quahog powder and genus quahog residue hydrogel comprises the following steps:

[0007] In order to ensure the original nutritional components of the genus quahog and extend the shelf life, the genus quahog slices are freeze-dried and ground into powder to obtain the genus quahog powder, the genus quahog powder is mixed with water, subjected to water bath ultrasound, and then vacuum filtered to obtain a filter residue, which is freeze-dried to obtain the genus quahog residue.

[0008] Sodium alginate powder is added into a heated water bath to obtain a sodium alginate solution, and gelatin is then added after the sodium alginate is completely dissolved into a homogeneous liquid to obtain a sodium alginate-gelatin mixed system.

[0009] After the gelatin in the sodium alginate-gelatin mixed system is completely dissolved, the temperature is lowered, and the genus arborescens powder and genus arborescens residue are added thereto respectively, and the genus arborescens powder hydrogel precursor and genus arborescens residue hydrogel precursor are obtained after mixing.

[0010] Ca was added to the hydrogel precursor of genkwa powder and genkwa residue, respectively. 2+ The solution becomes gelatinous, and the G units in the sodium alginate are exchanged with divalent calcium ions, so that the G units are cross-linked and accumulated to form an egg-shaped network structure, thereby obtaining the genus corydalis powder hydrogel and the genus corydalis residue hydrogel.

[0011] The method comprises the following steps: firstly preparing a sodium alginate-gelatin mixed system, then adding genkwa powder and genkwa residue to the sodium alginate-gelatin mixed system to obtain a genkwa powder hydrogel precursor and a genkwa residue hydrogel precursor, and finally adding Ca 2+ to the genkwa powder hydrogel precursor and the genkwa residue hydrogel precursor respectively. 2+ Solution, to obtain genus quahog powder hydrogel and genus quahog hydrogel; the invention uses genus quahog powder and genus quahog residue as the preparation source of antioxidant hydrogel carrier, and utilizes sodium alginate-Ca 2+ The solution method is the main method, in which gelatin is used instead of polymer to increase the mechanical strength of the gel. Sodium alginate molecules contain carboxyl groups, and Ca is added to its aqueous solution. 2+ The solution can exchange the G units in sodium alginate with divalent calcium ions, so that the G units are cross-linked and stacked to form an egg-shaped network structure, thereby obtaining a new type of hydrogel that is not easily damaged and has good flexibility.

[0012] In a preferred embodiment of the present invention, the mass concentration of genkwa root residue in the sodium alginate-gelatin mixed system is 0.05% to 10%.

[0013] In a preferred embodiment of the present invention, the mass concentration of genkwa powder in the sodium alginate-gelatin mixed system is 0.05% to 10%.

[0014] In a preferred embodiment of the present invention, the volume ratio of the mass of sodium alginate powder to water is 1 g to 2 g:100 mL.

[0015] In a preferred embodiment of the present invention, the volume ratio of the added gelatin to the sodium alginate solution is 1 g to 2 g:100 mL.

[0016] In a preferred embodiment of the present invention, the volume ratio of the genus corydalis powder to water is 1 g to 2 g: 40 to 50 mL.

[0017] In a preferred embodiment of the present invention, the freeze-drying temperature is -80°C to -70°C, the freeze-drying time is 10 h to 12 h, and the water bath ultrasonic temperature is 55°C to 60°C.

[0018] In a preferred embodiment of the present invention, the water bath temperature after heating is 75°C to 80°C, and the temperature is lowered to 55°C to 60°C. 2+ The mass concentration of the solution is 2% to 3%.

[0019] Another object of the present invention is to provide a hydrogel of genkwa residues prepared by any of the preparation methods described above.

[0020] The third object of the present invention is to provide an application of the above-mentioned genkwa hydrogel as a composite material matrix in a fruit preservation material.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention first prepares a sodium alginate-gelatin mixed system, then adds radix quahoga powder and radix quahoga residue to the sodium alginate-gelatin mixed system to obtain radix quahoga powder hydrogel precursor and radix quahoga residue hydrogel precursor, and finally adds Ca to the radix quahoga powder hydrogel precursor and the radix quahoga residue hydrogel precursor respectively. 2+ Solution, to obtain genus quahog powder hydrogel and genus quahog hydrogel; the invention uses genus quahog powder and genus quahog residue as the preparation source of antioxidant hydrogel carrier, and utilizes sodium alginate-Ca 2+ The solution method is the main method, in which gelatin is used instead of polymer to increase the mechanical strength of the gel. Sodium alginate molecules contain carboxyl groups, and Ca is added to its aqueous solution. 2+ The solution can exchange the G units in sodium alginate with divalent calcium ions, so that the G units are cross-linked and stacked to form an egg-shaped network structure, thereby obtaining a new type of hydrogel that is not easily damaged and has good flexibility.

[0023] 2. The series of genkwa powder and genkwa residue hydrogel obtained by the present invention use medicinal and edible substances as raw materials, and no toxic or harmful chemicals are introduced in the preparation process. The genkwa powder and genkwa residue hydrogel are soil degradable and have good environmental compatibility, and have the application prospect of becoming a plastic substitute material.

[0024] 3. The novel antioxidant hydrogel prepared by sodium alginate-calcium chloride method using radix daphne and radix daphne residue as raw materials has good biocompatibility and antioxidant properties. The preparation method of the hydrogel of the present invention does not use traditional cross-linking agents, thus avoiding chemical pollution and potential health risks.

[0025] 4. The novel genus quahog hydrogel and genus quahog residue hydrogel prepared by the present invention both have the potential to be used as composite material matrices in the field of fruit preservation. The preservation ability of the genus quahog hydrogel is stronger than that of the genus quahog residue hydrogel. The obtained hydrogels can effectively slow down the browning rate of the cross section of fresh-cut fruits, and the effect is better than that of plastic wrap, and both can prevent the fruit from losing water. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is the technical roadmap of the present invention.

[0027] Figure 2 The scanning electron micrographs of the novel antioxidant hydrogels of genkwa powder and genkwa residue with a mass concentration of 1% prepared by the present invention, wherein (a) is the genkwa residue hydrogel; and (b) is the genkwa powder hydrogel.

[0028] Figure 3 The infrared spectra of a series of quahog root powder and quahog root residue hydrogels prepared by the present invention, from top to bottom in the figure are: YG0.05 represents 0.05% quahog root powder hydrogel; YG1 represents 1% quahog root powder hydrogel; YG10 represents 10% quahog root powder hydrogel; Z0.05 represents 0.05% quahog root residue hydrogel; Z1 represents 1% quahog root residue hydrogel; Z10 represents 10% quahog root residue hydrogel.

[0029] Figure 4 In the figure, a-1 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 0.05% of coriander root powder, and a-2 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 1% of coriander root powder.

[0030] Figure 5 In the figure, a-3 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 5% of coriander root powder, and a-4 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 10%.

[0031] Figure 6 In the figure, b-1 is a schematic diagram of thermogravimetric analysis of hydrogel of genus quaternium residue with a mass concentration of 0.05%, and b-2 is a schematic diagram of thermogravimetric analysis of hydrogel of genus quaternium residue with a mass concentration of 1%.

[0032] Figure 7 In the figure, b-3 is a schematic diagram of thermogravimetric analysis of hydrogel of coriander root residue with a mass concentration of 5%, and b-4 is a schematic diagram of thermogravimetric analysis of hydrogel of coriander root powder with a mass concentration of 10%.

[0033] Figure 8Schematic diagram of the properties of the new genus arborvitae residue gel of different concentrations prepared by the present invention; wherein a is a demonstration of the transparency of the new genus arborvitae residue hydrogel, from left to right are 0.05%, 1%, 5% and 10% mass concentration respectively; b is a demonstration of the thickness of the new genus arborvitae residue hydrogel, 1-4 in b are 0.05%, 1%, 5% and 10% mass concentration respectively; c is a demonstration diagram of the adhesion of the new genus arborvitae hydrogel.

[0034] Fig. 9 This is a schematic diagram of the comparison of the new genus stalk hydrogel prepared by the present invention before and after drying at different temperatures, wherein a is the genus stalk hydrogel in a wet state, from left to right: 3% genus stalk hydrogel at room temperature, 37°C, 40°C, and 5°C; b is the genus stalk hydrogel after complete drying, from left to right: 3% genus stalk hydrogel at room temperature, 37°C, 40°C, and 5°C; 1 is a front view of the genus stalk hydrogel; 2 is a side view of the genus stalk.

[0035] Fig.10 It is the water retention rate of the 3% novel genkwa residue hydrogel at different temperatures of the present invention.

[0036] Fig.11 This is a volume change trend diagram of the newly prepared genus quahog residue hydrogel in water with different concentrations of the present invention.

[0037] Fig.12 It is a schematic diagram of the water retention of the novel genus quahog powder and genus quahog residue hydrogel of different concentrations of the present invention, wherein a is the genus quahog hydrogel, and b is the genus quahog residue hydrogel; wherein 1-4 are mass concentrations of 0.05%, 1%, 5%, and 10%, respectively, 1 represents a moist genus quahog or genus quahog residue hydrogel; and 2 represents a completely dehydrated genus quahog or genus quahog residue hydrogel.

[0038] Fig.13 The present invention shows the water retention rate of the freshly prepared genkwa powder and genkwa residue hydrogel at different concentrations at room temperature.

[0039] Fig.14 Schematic diagram of the degradability of the novel hydrogel of genus quahog residue of the present invention; wherein a is the 3% novel hydrogel of genus quahog residue before drying; b is the fresh 3% novel hydrogel of genus quahog residue before burying; c is the 3% novel hydrogel of genus quahog residue after drying before burying; d is the degradation state of the dried 3% novel hydrogel in c and the fresh 3% novel hydrogel of genus quahog residue in b after burying for 35 days; e is all the residues of the dried 3% novel hydrogel in c and the fresh 3% novel hydrogel of genus quahog residue in b after burying for 65 days; f is the organisms dug out together with the residues after burying for 65 days.

[0040] Fig.15 This is a schematic diagram of the antioxidant activity of aqueous solutions of genkwa root at different concentrations according to the present invention.

[0041] Fig.16 This is a schematic diagram of the antioxidant activity of aqueous solutions of genkwa root residue at different concentrations according to the present invention.

[0042] Fig.17 Schematic diagram of the reproducibility of the novel 3% genkwa residue hydrogel of the present invention; a is an air-dried 3% genkwa residue hydrogel sheet; b is an air-dried 3% genkwa residue hydrogel sheet after being soaked in water for 24 hours.

[0043] Fig.18 The schematic diagram of the composite material obtained by loading carbon quantum dots with 1% novel genkwa residue hydrogel of the present invention; wherein a is the morphology of the composite material under natural light; and b is the morphology of the composite material under ultraviolet light.

[0044] Fig.19 It is a schematic diagram of fresh-cut apples of the present invention after different treatments at room temperature; in each figure, from top to bottom and from left to right, the treatment methods are respectively covering with 0.05% genus arborvitae hydrogel, covering with 0.05% genus arborvitae residue hydrogel, covering with 1% genus arborvitae hydrogel, covering with 1% genus arborvitae residue hydrogel, covering with 5% genus arborvitae hydrogel, covering with 5% genus arborvitae residue hydrogel, covering with 10% genus arborvitae hydrogel, covering with 10% genus arborvitae residue hydrogel, blank control (no treatment), positive control (covered with plastic wrap); wherein a represents the apple just after cutting without treatment; b represents the apple at room temperature 0h after treatment; c represents the apple at room temperature 3h after treatment; d represents the apple at room temperature 8h after treatment; e represents the apple at room temperature 24h after treatment; f represents the apple at room temperature 48h after treatment; g represents the apple at room temperature 48h after treatment with the covering removed.

[0045] Fig. 20 This is a schematic diagram of the quality changes of fresh-cut apples of the present invention after different treatments at room temperature for 48 hours. DETAILED DESCRIPTION

[0046] The following is a detailed description of the technical solutions in the embodiments of the present invention in combination with the preferred embodiments and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] It should be noted that all professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specifically stated, various raw materials, reagents, instruments and equipment used in the following embodiments of the present invention can be purchased from the market or prepared by existing methods.

[0048] The root of radix guajava, called "Niuma" in Tibetan, is commonly known as Pancai. It is mainly distributed in high-altitude areas above 3,500 meters above sea level. It belongs to the genus Brassica in the family Cruciferae. It is a biennial herb. Its tubers are mainly edible, and can also be used as medicine and animal feed. It is an important crop in plateau areas. The famous Tibetan medical book "Four Medical Classics" records: "The root of guajava is sweet and warm in nature, and has the effects of clearing heat and detoxifying, nourishing and increasing oxygen." As a typical medicinal and edible plant, the research on how to further develop guajava has become increasingly hot in recent years. The current research direction focuses on the exploration and application of the antioxidant and anti-fatigue effects of guajava extracts such as guajava polysaccharides. After the guajava extract is extracted by water bath filtration, a large amount of waste residue will inevitably be produced. The waste residue is rich in macromolecules such as cellulose remaining after water extraction, and may still contain some antioxidant active substances. Combined with its structural characteristics and good biosafety, the guajava residue is no less than a good precursor for the preparation of green and non-toxic hydrogels.

[0049] Sodium alginate (SA) is a linear polymer composed of 1,4-poly-β-D-mannuronic acid and α-L-guluronic acid extracted from brown algae. It is non-toxic and was approved by the FDA as a "direct edible ingredient" in 1983. Sodium alginate molecules contain carboxyl groups. When divalent metal ions such as Ca are added to their aqueous solution, 2+ , Cu 2+ The divalent cations can be exchanged in the G units, so that the G units are cross-linked and stacked to form an egg-shaped network structure, thereby obtaining a hydrogel.

[0050] In view of this, the present invention selects genus corydalis powder and genus corydalis residue as the source of preparation of antioxidant hydrogel carriers, uses sodium alginate-calcium chloride method as the main method, replaces the polymer with gelatin to increase the mechanical strength of the gel, and designs and prepares a new antioxidant hydrogel that can meet daily use, will not be easily damaged, and has good flexibility. The effects of different concentrations of genus corydalis powder and genus corydalis residue components on the obtained hydrogel, including physical and chemical properties, water absorption, water retention rate and antioxidant activity, are investigated to explore the application prospects of the obtained new genus corydalis and genus corydalis residue hydrogel as carrier matrix materials.

[0051] Example 1

[0052] A method for preparing a hydrogel of genkwa root residue comprises the following steps:

[0053] (1) Preparation of radix quatrainii residue: The radix quatrainii slices collected in Tibet were freeze-dried and then ground into powder to obtain freeze-dried powder. The freeze-dried powder was added with distilled water at a solid-liquid ratio of 1 g:43 mL and ultrasonicated for 55 min in a water bath at 60°C. The mixture was then vacuum filtered. The liquid portion was the radix quatrainii extract. The filtrate was pre-cooled at -80°C for 12 h, freeze-dried to complete dryness, and stored in a refrigerator to obtain the radix quatrain residue for later use.

[0054] (2) Hydrogel preparation

[0055] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare a 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare a 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 3% genkwa residue, and mix thoroughly to obtain a genkwa residue hydrogel precursor;

[0056] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur residue hydrogel precursor until the whole thing becomes gelatinous, take it out and wash it with distilled water to obtain the genus larkspur residue hydrogel.

[0057] Example 2

[0058] A method for preparing a hydrogel of genkwa root residue comprises the following steps:

[0059] (1) Preparation of radix quatrainii residue: The radix quatrainii slices collected in Tibet were freeze-dried and then ground into powder to obtain freeze-dried powder. The freeze-dried powder was added with distilled water at a solid-liquid ratio of 1 g:43 mL and ultrasonicated for 55 min in a water bath at 60°C. The mixture was then vacuum filtered. The liquid portion was the radix quatrainii extract. The filtrate was pre-cooled at -80°C for 12 h, freeze-dried to complete dryness, and stored in a refrigerator to obtain the radix quatrain residue for later use.

[0060] (2) Hydrogel preparation

[0061] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare a 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare a 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 0.05% genkwa residue, and mix thoroughly to obtain a genkwa residue hydrogel precursor;

[0062] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur residue hydrogel precursor until the whole thing becomes gelatinous, take it out and wash it with distilled water to obtain the genus larkspur residue hydrogel.

[0063] Example 3

[0064] A method for preparing a hydrogel of genkwa root residue comprises the following steps:

[0065] (1) Preparation of radix quatrainii residue: The radix quatrainii slices collected in Tibet were freeze-dried and then ground into powder to obtain freeze-dried powder. The freeze-dried powder was added with distilled water at a solid-liquid ratio of 1 g:43 mL and ultrasonicated for 55 min in a water bath at 60°C. The mixture was then vacuum filtered. The liquid portion was the radix quatrainii extract. The filtrate was pre-cooled at -80°C for 12 h, freeze-dried to complete dryness, and stored in a refrigerator to obtain the radix quatrain residue for later use.

[0066] (2) Hydrogel preparation

[0067] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 1% genkwa residue, and mix thoroughly to obtain genkwa residue hydrogel precursor;

[0068] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur residue hydrogel precursor until the whole thing becomes gelatinous, take it out and wash it with distilled water to obtain the genus larkspur residue hydrogel.

[0069] Example 4

[0070] A method for preparing a hydrogel of genkwa root residue comprises the following steps:

[0071] (1) Preparation of radix quatrainii residue: The radix quatrainii slices collected in Tibet were freeze-dried and then ground into powder to obtain freeze-dried powder. The freeze-dried powder was added with distilled water at a solid-liquid ratio of 1 g:43 mL and ultrasonicated for 55 min in a water bath at 60°C. The mixture was then vacuum filtered. The liquid portion was the radix quatrainii extract. The filtrate was pre-cooled at -80°C for 12 h, freeze-dried to complete dryness, and stored in a refrigerator to obtain the radix quatrain residue for later use.

[0072] (2) Hydrogel preparation

[0073] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare a 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare a 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 5% mass concentration of genkwae slag, and mix thoroughly to obtain a genkwae slag hydrogel precursor;

[0074] S2. Prepare 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur residue hydrogel precursor until the whole thing becomes gelatinous, take out and wash with distilled water to obtain the genus larkspur residue hydrogel.

[0075] Example 5

[0076] A method for preparing a hydrogel of genkwa root residue comprises the following steps:

[0077] (1) Preparation of radix quatrainii residue: The radix quatrainii slices collected in Tibet were freeze-dried and then ground into powder to obtain freeze-dried powder. The freeze-dried powder was added with distilled water at a solid-liquid ratio of 1 g:43 mL and ultrasonicated for 55 min in a water bath at 60°C. The mixture was then vacuum filtered. The liquid portion was the radix quatrainii extract. The filtrate was pre-cooled at -80°C for 12 h, freeze-dried to complete dryness, and stored in a refrigerator to obtain the radix quatrain residue for later use.

[0078] (2) Hydrogel preparation

[0079] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare a 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare a 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 10% mass concentration of genkwae slag, and mix thoroughly to obtain a genkwae slag hydrogel precursor;

[0080] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur residue hydrogel precursor until the whole thing becomes gelatinous, take it out and wash it with distilled water to obtain the genus larkspur residue hydrogel.

[0081] Example 6

[0082] A method for preparing a hydrogel of genkwa root powder comprises the following steps:

[0083] (1) Preparation of radix corydalis powder: The radix corydalis collected in Tibet was sliced ​​and freeze-dried and then ground into powder to obtain freeze-dried powder, i.e. radix corydalis powder.

[0084] (2) Hydrogel preparation

[0085] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 0.05% genkwa powder, and mix thoroughly to obtain genkwa hydrogel precursor;

[0086] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur hydrogel precursor until the whole thing becomes gelatinous, take out and wash with distilled water to obtain the genus larkspur hydrogel.

[0087] Example 7

[0088] A method for preparing a hydrogel of genkwa root powder comprises the following steps:

[0089] (1) Preparation of radix corydalis powder: The radix corydalis collected in Tibet was sliced ​​and freeze-dried and then ground into powder to obtain freeze-dried powder, i.e. radix corydalis powder.

[0090] (2) Hydrogel preparation

[0091] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 1% genkwa powder, and mix thoroughly to obtain genkwa hydrogel precursor;

[0092] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur hydrogel precursor until the whole thing becomes gelatinous, take out and wash with distilled water to obtain the genus larkspur hydrogel.

[0093] Example 8

[0094] A method for preparing a hydrogel of genkwa root powder comprises the following steps:

[0095] (1) Preparation of radix corydalis powder: The radix corydalis collected in Tibet was sliced ​​and freeze-dried and then ground into powder to obtain freeze-dried powder, i.e. radix corydalis powder.

[0096] (2) Hydrogel preparation

[0097] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 5% genkwa powder, and mix thoroughly to obtain genkwa hydrogel precursor;

[0098] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur hydrogel precursor until the whole thing becomes gelatinous, take out and wash with distilled water to obtain the genus larkspur hydrogel.

[0099] Example 9

[0100] A method for preparing a hydrogel of genkwa root powder comprises the following steps:

[0101] (1) Preparation of radix corydalis powder: The radix corydalis collected in Tibet was sliced ​​and freeze-dried and then ground into powder to obtain freeze-dried powder, i.e. radix corydalis powder.

[0102] (2) Hydrogel preparation

[0103] S1. Heat the distilled water in a water bath with a magnetic stirrer to 80°C, add sodium alginate powder to prepare 2g / 100mL sodium alginate solution, wait until the sodium alginate is fully dissolved into a homogeneous liquid, then add gelatin to prepare 4g / 100mL sodium alginate-gelatin mixed system, wait until the gelatin is completely dissolved, slowly cool to 60°C, add 0.05% genkwa powder, and mix thoroughly to obtain genkwa hydrogel precursor;

[0104] S2. Prepare another 2% calcium chloride solution, add the calcium chloride solution to the genus larkspur hydrogel precursor until the whole thing becomes gelatinous, take out and wash with distilled water to obtain the genus larkspur hydrogel.

[0105] Performance Characterization

[0106] 1. Gel properties determination

[0107] Add genmai dahliae powder / genmai dahliae residue to hydrogel precursors, prepare genmai dahliae residue hydrogel precursors with mass concentrations of 0.05%, 1%, 5% and 10%, draw 1mL with a syringe and evenly draw lines on a glass slide, cover it with another glass slide, squeeze it slightly until it is even, put it into a 2-3% calcium chloride solution, remove the glass slide and wash it with distilled water after the reaction is completed, and place it on different objects to observe its transmittance. Pull the genmai dahliae residue hydrogel by hand with increasing force until it tears, observe its toughness, and bend and fold the prepared genmai dahliae residue hydrogel to observe the softness of the material.

[0108] 2. Water retention determination

[0109] The genus quahog / genus quahog residue was added to the hydrogel precursor to prepare columnar genus quahog / genus quahog residue hydrogels with mass concentrations of 0.05%, 1%, 5% and 10%, respectively. After the preparation, the hydrogel was placed in distilled water and the mass was weighed regularly until the mass remained unchanged. The hydrogel was drained and placed at room temperature away from light. The weight change was monitored regularly until the mass was constant. The data was sorted and graphed, and the water retention rate, water retention time and water loss curve at different genus quahog concentrations were calculated.

[0110] In order to further calculate the water retention rate of the hydrogel and investigate its water retention performance, the present invention placed the prepared 3g / 100mL genkwa residue hydrogel at room temperature, 4°C, 37°C and 40°C, protected from light, monitored its water loss weight change until the mass was constant, sorted the data, and calculated the water retention rate, water retention time and water loss curve of the material at different temperatures. The water retention rate (WR) calculation formula of the present invention is as follows:

[0111]

[0112] Where W t is the mass of hydrogel measured at a certain time point, W s is the weight of the hydrogel in a completely wet, saturated state, W dIt is the mass of the hydrogel in a completely dry, i.e. completely dehydrated state.

[0113] 3. Degradation Experiment

[0114] The same type of hydrogel was prepared and dried / carbonized / soaked in water respectively. Then, a 15 cm deep pit was dug in the field environment, and the hydrogel sample was placed in it and buried. It was marked and dug out and observed every 30 days and then put back until the end of the experiment of the present invention, which lasted for a total of 90 days. The data was collated and the weight changes were plotted.

[0115] 4. Antibacterial activity experiment

[0116] Preparation of genus dahurica extract: Add genus dahurica powder to 4% NaOH solution at a ratio of 1:20, stir at 60-80℃ for 36h, centrifuge the mixture to obtain the precipitate, wash with distilled water and dry. Prepare NaOH / urea / H2O solution at a ratio of 6:4:90, add the precipitate to the NaOH / urea / H2O mixed solution at a ratio of 1:50, stir at room temperature for 1h, then freeze at -12℃ for 12h, heat at 60-80℃ after thawing, stir, filter to obtain genus dahurica extract, adjust pH to neutral for later use.

[0117] Prepare hydrogels with different concentrations of radix quatica / radix quatica residue for later use; prepare solid culture medium; sterilize solid culture medium in high pressure steam sterilizer, pipette tip, distilled water, and saline for later use; sterilize on ultraviolet light for 30 minutes on clean bench and then perform aseptic operation. Staphylococcus aureus and Escherichia coli were selected as experimental strains, and colonies were scraped with an inoculation loop and placed in saline to shake to obtain bacterial solution. The bacterial solution was added to a 96-well plate microplate reader to measure the concentration of the bacterial solution at OD600, and then diluted with saline to 1x10 9 For observing antibacterial activity, gradient dilution to 1x10 5 Used for counting plates. Use the tip of the sample gun to press and punch a hole in the inoculated culture medium and put the hydrogel into the hole. After adding the sample, place the plate in a constant temperature incubator at 37℃ for 24 hours to observe the growth of the colony. Prepare another extract of radix daphne and add it to the hydrogel instead of radix daphne, repeat the above steps, and observe the inhibition zone.

[0118] 5. Antioxidant activity test

[0119] Preparation of genus croton residue / genus croton extract: Take 10g of genus croton / genus croton residue and mix it with 90mL of distilled water and let it stand for 10min. Aspirate the supernatant with a syringe and install a disposable syringe water filter membrane to filter to obtain the extract. Gradually dilute it to concentrations of 10g / 100mL, 8g / 100mL, 4g / 100mL, 2g / 100mL, 1g / 100mL, 0.8g / 100mL, 0.4g / 100mL, 0.2g / 100mL and 0g / 100mL for stand-by use.

[0120] Determination of total reducing capacity: prepare 1% potassium ferrocyanide solution, 10% trichloroacetic acid solution, and 0.1% ferric chloride solution in advance, use 0.1% Vc aqueous solution as positive control, and keep it away from light for immediate use. Turn on the microplate reader and warm it up for use. Take 1mL of the extract and place it in a 10mL disposable centrifuge tube, add 1mL of 0.2mol / L, pH=6.6 phosphate buffer, add 1mL of 1% potassium ferrocyanide solution, heat it in a 50℃ water bath for 20min, then quickly put it in an ice bucket for 5min, add 1mL of 10% trichloroacetic acid solution, centrifuge at 4000 rpm for ten minutes, take 1mL of the supernatant, add 1mL of distilled water, 1mL of 0.5% ferric chloride solution, shake well, let stand at room temperature for 10min, add it to 4 wells of each concentration in a 96-well plate, measure the absorbance by OD700 of the microplate reader, and delete one outlier from the four wells of each concentration to calculate the total reducing capacity. Calculation formula:

[0121]

[0122] 6. Reproducibility Experiment

[0123] Prepare the gel slices of genus quatrain / genus quatrain residue, dry them in the sun after swelling with water, place them away from light for 30 days, then swell with water, and observe whether the material recovers its flexibility.

[0124] 7. Hydrogel Series Characterization

[0125] Scanning electron microscope sample processing: Prepare a fresh sample of 1% hydrogel of genkwa / genkwa residue, cut it into thin slices, and stick it to the sample stage with conductive tape for sample delivery.

[0126] Thermogravimetric analysis, elemental analysis, sample processing: 0.05, 1, 5, 10g / 100mL hydrogel of genus quahog / genus quahog residue was prepared and loaded on a disposable culture dish with Monza hole plastic wrap and placed in a -80℃ refrigerator for 12h. Freeze-dry in a freeze dryer for 24h, grind into powder and put into 2mL conical bottom centrifuge tube for sample delivery.

[0127] Infrared spectrum: The sample is freeze-dried into powder, mixed with potassium bromide to make tablets, and placed in an infrared spectrometer for analysis.

[0128] Results Analysis

[0129] Figure 2 The scanning electron microscope images of the novel 1% mass concentration of quahog powder and quahog residue antioxidant hydrogel prepared by the present invention, wherein (a) is quahog residue hydrogel; (b) is quahog powder hydrogel. The obtained novel quahog powder and quahog residue hydrogels both show a small porous and dense structure under the electron microscope, and the surface of the quahog residue hydrogel is rougher. From the appearance, both are light yellow soft solids, and the transparency decreases with the increase of the concentration of quahog powder and quahog residue. At the same concentration, the color of the quahog powder hydrogel is darker than that of the quahog residue hydrogel.

[0130] Figure 3This is the infrared spectrum of the series of quahog powder and quahog residue hydrogel prepared by the present invention. From top to bottom, the following are: YG0.05 represents 0.05% quahog powder hydrogel; YG1 represents 1% quahog powder hydrogel; YG10 represents 10% quahog powder hydrogel; Z0.05 represents 0.05% quahog powder residue hydrogel; Z1 represents 1% quahog residue hydrogel; Z10 represents 10% quahog residue hydrogel. Figure 3 As shown in Figure 2, overall, the functional groups contained in different concentrations of genkwa powder and genkwa residue are roughly the same, such as about 3500cm -1 There are OH stretching vibration peaks at 2900 cm -1 On the left and right, CH symmetric stretching vibration appears, about 1059cm -1 The absorption peak of COC is shown at 1650cm -1 The nearby absorption peak can be attributed to the stretching vibration peak of C=C, which indicates that the activities contained in the series of hydrogels of different concentrations are relatively similar and do not show obvious differences in the infrared spectra.

[0131] Figure 4 In the figure, a-1 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 0.05% of coriander root powder, and a-2 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 1% of coriander root powder. Figure 5 In the figure, a-3 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 5% of coriander root powder, and a-4 is a schematic diagram of thermogravimetric analysis of hydrogel with a mass concentration of 10%. Figure 6 In the figure, b-1 is a schematic diagram of thermogravimetric analysis of hydrogel of genus quaternium residue with a mass concentration of 0.05%, and b-2 is a schematic diagram of thermogravimetric analysis of hydrogel of genus quaternium residue with a mass concentration of 1%. Figure 7 In the figure, b-3 is a schematic diagram of thermogravimetric analysis of hydrogel of coriander root residue with a mass concentration of 5%, and b-4 is a schematic diagram of thermogravimetric analysis of hydrogel of coriander root powder with a mass concentration of 10%. In general, coriander root powder hydrogel produced three pyrolysis after 1% concentration, while coriander root residue hydrogel only cracked twice except for three pyrolysis at 1% concentration. The difference may be due to the high content of polysaccharide active substances contained in coriander root powder. For coriander root powder hydrogel, the temperature of the initial pyrolysis decreased with the increase of coriander root powder concentration, gradually decreasing from 105℃ at 0.05% coriander root hydrogel to 80℃ at 10% coriander root hydrogel, and the subsequent pyrolysis temperatures showed the same trend; while for coriander root residue hydrogel, the relationship between the pyrolysis temperature and the added concentration of coriander root residue was not as obvious as that of coriander root powder. In addition, it can be seen that the first pyrolysis temperature of coriander root residue hydrogel is higher than that of coriander root residue at the same concentration. This is consistent with the difference in the number of pyrolysis times seen in the figure of the present invention, which shows that the hydrogel of coriander powder does contain more thermally unstable components than the hydrogel of coriander residue. According to the preparation method of coriander residue, this component is most likely a polysaccharide.

[0132] Figure 8 Schematic diagram of the properties of the new hydrogel of different concentrations of scutellaria baicalensis residue prepared by the present invention. Among them, a is a demonstration of the transparency of the new hydrogel of scutellaria baicalensis residue, which are 0.05%, 1%, 5% and 10% mass concentration from left to right; b is a demonstration of the thickness of the new hydrogel of scutellaria baicalensis residue, and c is a demonstration of the adhesion of the new hydrogel of scutellaria baicalensis powder. 1-4 in b are 0.05%, 1%, 5% and 10% mass concentrations, respectively. It can be seen from Figure 5-a that the hydrogel is mostly light yellow jelly, and its light transmittance decreases with the increase of the content of scutellaria baicalensis residue. It can be seen from Figure 5-b that when comparing the light transmittance, the thickness of the hydrogel is about 2mm. During the experiment, the hydrogel is homogeneous, soft and elastic, with no obvious difference in flexibility, and no creases will be produced when folded 90° in a wet state. After drying, it is like plastic paper, with reduced toughness and easy to break when folded. It can be seen from Figure 5-c that the hydrogel can adhere to the surface of the object when wet, and there is no residue at the bonding point when it is dried and peeled off. This shows that the hydrogel material prepared in this work has good light transmittance and satisfactory adhesion, and can be used as a potential dressing material matrix, laying the foundation for further application.

[0133] Fig. 9 This is a schematic diagram of the comparison of the new genus slag hydrogel prepared by the present invention before and after drying at different temperatures, wherein a is the genus slag hydrogel in a wet state, from left to right: 3% genus slag hydrogel at room temperature, 37°C, 40°C, 5°C; b is the genus slag hydrogel after complete drying, from left to right: 3% genus slag hydrogel at room temperature, 37°C, 40°C, 5°C; 1 is a front view of the genus slag hydrogel; 2 is a side view of the genus slag. Water retention capacity is an important evaluation parameter for the later application of hydrogel. In order to study the effect of different temperatures on the water retention capacity of hydrogel, the present invention selects genus slag gel as the research object, and investigates the water retention of the obtained hydrogel under common temperature application conditions, such as 37°C. The results are as shown in the figure. Fig. 9 As shown. Fig. 9 It can be seen that the hydrogels all show the characteristic of shrinking after drying, but the overall columnar structure still exists.

[0134] Fig.10The water retention rate of the 3% new hydrogel of genkwa root residue at different temperatures of the present invention is to compare whether there is a difference in the water retention rate of genkwa root residue at four different temperatures: room temperature, 37°C, 40°C, and 5°C. By drawing a QQ graph and the Shapiro-wilk test, it is suggested that the data do not obey the normal distribution. Therefore, the Friedman test was used to analyze the data. The results showed that the water retention rate of the 3% hydrogel of genkwa root residue at room temperature was 64.53% at 1200 min, the water retention rate at 37°C was 19.68%, the water retention rate at 40°C was 16.62%, and the water retention rate at 5°C was 82.12%; the water retention rate at room temperature was 42.93% at 2160 min, the water retention rate at 37°C was 2.43%, the water retention rate at 40°C was 1.82%, and the water retention rate at 5°C was 69.84%; 6000 min The water retention rate was 5.21% at room temperature, 0.00% at 37℃, 0.00% at 40℃, and 21.10% at 5℃; at 13200min, the water retention rate was 0.00% at room temperature, 0.00% at 37℃, 0.00% at 40℃, and 4.19% at 5℃, with statistically significant differences (x^2=116.489, P<0.001). Further pairwise comparison using the Bonferroni method showed that there was no statistically significant difference in the 40℃-37℃ group (P=0.435), while there were statistically significant differences in the 5℃-room temperature group, 5℃-40℃ group, 5℃-37℃ group, room temperature-40℃ group, and room temperature-37℃ group (P<0.05). The 3% genus coriander residue hydrogel has the best water retention capacity at 5°C, reaching constant weight after 15,000 min (nearly 10 days); it completely loses water after 7,500 min (nearly 5 days) at room temperature; at 37°C and 40°C, the water retention performance is poor, losing water to constant weight after 2,500 min (nearly 1 day).

[0135] Fig.11 The quality change trend diagram of the newly prepared genus slag hydrogel of different concentrations in water of the present invention is shown. From the quality change curve, it can be seen that the quality of the genus slag hydrogels of different concentrations shows a trend of first decreasing and then increasing after gradually absorbing water. Combined with the preparation process of the present invention, this may be because the hydrogel absorbs a large mass of calcium chloride solution during preparation, and the mass decreases when the water with a smaller mass gradually replaces the calcium chloride solution at the initial stage of water absorption; as the replacement is completed and further water is absorbed, the quality of the hydrogel gradually recovers.

[0136] Fig.12The figure is a schematic diagram of the water retention of the novel hydrogel of genus quahog and genus dregs of genus quahog at different concentrations of the present invention, wherein a is hydrogel of genus quahog and b is hydrogel of genus dregs of genus quahog; wherein 1-4 are mass concentrations of 0.05%, 1%, 5%, and 10%, respectively, 1 represents a moist hydrogel of genus quahog or genus dregs of genus quahog; 2 represents a completely dehydrated hydrogel of genus quahog or genus dregs of genus quahog. It can be seen that the water retention capacity of the obtained novel hydrogel of genus quahog and genus dregs of genus decreases with the increase of ambient temperature; at the same concentration, the water retention performance of hydrogel of genus quahog is stronger than that of hydrogel of genus dregs of genus quahog.

[0137] Fig.13 It is the water retention rate of the newly prepared coriander root powder and coriander root residue hydrogel at different concentrations at room temperature of the present invention. After statistical analysis of the water retention rate of the obtained series of hydrogels, it can be found that the water retention curves of coriander root powder and coriander root residue hydrogels at different concentrations have similar trends. Among them, 1% coriander root hydrogel showed better water retention efficiency, and 0.05% coriander root residue hydrogel had poor water retention efficiency. In comparison, at the same concentration, the water retention performance of coriander root powder hydrogel is slightly better than that of coriander root residue hydrogel. In general, the higher the ambient temperature of coriander root powder and coriander root residue hydrogel, the lower the water retention rate, but the overall difference in water retention of coriander root powder and coriander root residue hydrogel is not very obvious.

[0138] Fig.14 Schematic diagram of the degradability of the novel hydrogel of genus spatholobi; wherein a is the 3% novel hydrogel of genus spatholobi before drying; b is the fresh 3% novel hydrogel of genus spatholobi before burying; c is the 3% novel hydrogel of genus spatholobi after drying and before burying; d is the degradation state of the dried 3% novel hydrogel in c and the fresh 3% novel hydrogel of genus spatholobi after burying for 35 days (24.1.29-3.4); e is all the residues (3.4-4.4) of the dried 3% novel hydrogel in c and the fresh 3% novel hydrogel of genus spatholobi after burying for 65 days; f is the organisms dug out together with the residues after burying for 65 days. Combined with the experimental design idea of ​​the present invention, the environmental compatibility of the obtained hydrogel is an important factor that needs to be investigated. Therefore, the present invention selects 3% hydrogel of genus spatholobi as the research subject, and selects the hydrogels in a wet state and after drying, respectively, to carry out soil degradation experiments for 95 consecutive days. The results are as follows Fig.14 As shown. Fig.14 -a to 11-e, it can be seen that the hydrogel of genus larvae residue can be slowly degraded in the soil, and no material fragments were dug out from the landfill after 95 days. Fig.14 The organisms shown in -f may indicate that the hydrogel obtained in this work has good environmental compatibility and can be completely degraded in the soil. In summary, the environmental compatibility and soil degradability of the obtained hydrogel are good, and there is no obvious residue in the soil after degradation.

[0139] Fig.15 This is a schematic diagram of the antioxidant activity of aqueous solutions of genkwa powder of different concentrations in the present invention. Fig.16This is a schematic diagram of the antioxidant activity of aqueous solutions of genus spatholobi with different concentrations in the present invention. It can be seen that the antioxidant activity of the obtained novel genus spatholobi powder and genus spatholobi residue hydrogel increases with the increase of the added concentration of genus spatholobi and genus spatholobi residue. Compared with the genus spatholobi residue hydrogel, the genus spatholobi powder hydrogel exhibits stronger antioxidant activity.

[0140] Fig.17 The figure is a schematic diagram of the reproducibility of the novel 3% genus slag hydrogel of the present invention. A is an air-dried 3% genus slag hydrogel sheet; B is an air-dried 3% genus slag hydrogel sheet soaked in water for 24 hours. The obtained novel genus slag hydrogel has good water absorption and reproducibility. The genus slag hydrogel sheet shows obvious shrinkage after complete water loss, and the color deepens and the volume decreases; after absorbing water for 24 hours, the appearance of the genus slag hydrogel almost returns to the original wet state, and the volume expands from the original 30mm*5mm*7mm to 74mm*20mm*1mm. This shows that the genus slag hydrogel obtained by the present invention has an important basis for repeated use and good water absorption and reproducibility.

[0141] Composite material carrier matrix application results

[0142] The obtained hydrogel has the advantages of good environmental compatibility and good water absorption reproducibility, and can be used as a loading matrix for composite materials and obtain wider applications. Fig.18 As shown, the hydrogel obtained after modification with carbon quantum dots is still soft and can be shaped arbitrarily. After irradiation with ultraviolet light, it is found that the characteristic fluorescence of carbon quantum dots is not affected. This shows that the hydrogel obtained by the present invention may be used as a substrate material to provide an effective carrier for further loading other new nanomaterials. The covering is removed after the fruit is treated at room temperature for 48 hours.

[0143] Fruit preservation application

[0144] According to the above test results, the obtained hydrogel has the advantages of strong water retention, good antioxidant capacity, good flexibility, and reusability. Therefore, the present invention applies the obtained series of hydrogels to the preservation of fresh-cut fruits to explore its application potential in the food field. Apples were selected as experimental objects to investigate the actual application scenarios of the obtained series of hydrogels. The results are as follows: Fig.19As shown. Comparing a and b, it can be seen that the cut surface of apples covered with hydrogels is whiter than that of untreated apples, indicating that hydrogels have the ability to slow down the browning of apples. Compared with the apples in the positive control group covered with plastic wrap, the cut surface of apples in the hydrogel group is generally whiter, which also shows from one aspect that coriander and coriander residue hydrogels do have certain antioxidant activity and can delay the oxidation of divalent iron ions in apples; by comparing the color of apples treated with coriander powder and coriander residue hydrogels at the same concentration, it can be found that the cut surface of apples treated with coriander hydrogel at the same concentration is whiter than that of apples treated with coriander residue hydrogel; by longitudinally comparing the cut surface color of apples treated with hydrogels of different concentrations under the same material, it can be found that the higher the content of coriander or coriander residue added in the hydrogel of the same material, the whiter the apple cut surface. This phenomenon also further proves that the antioxidant capacity of the new hydrogel is due to the addition of coriander or coriander residue. From the moisture content of the cut surface of the apples 48 hours after different treatments shown in Figure g, it can be found that the moisture content of the apples treated with plastic wrap is greater than that of the groups treated with various hydrogels and greater than that of the group not treated. In order to further compare the moisture loss of the fruits under different treatments, the present invention measured the quality of each treatment group before and after treatment. Fig. 20 It can be seen that the apples in the blank control group without treatment lost the most water, reducing nearly 14% of the total mass. The apples in the positive control group covered with plastic wrap lost the least water, reducing nearly 1% of the total mass. The apples in the hydrogel-treated group lost less water than the blank control group but more than the positive control group. This shows that the hydrogel prepared by the present invention does have a certain ability to prevent the loss of water in fruits. In summary, the series of hydrogels obtained by the present invention have the possibility of being used in fruit preservation, and the materials and concentrations are selectively selected and applied according to different actual emphases.

[0145] It should be noted that when the present invention involves a numerical range, it should be understood that the two endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as those in the embodiments, in order to avoid redundancy, the present invention describes a preferred embodiment. Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the attached claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0146] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing genus quahog powder and genus quahog residue hydrogel, characterized in that: The following steps are involved: The genus yanhus slices are freeze-dried and ground to obtain genus yanhus powder, the genus yanhus powder is mixed with water, ultrasonicated, and vacuum filtered to obtain a filter residue, and the filter residue is freeze-dried to obtain genus yanhus residue; Adding sodium alginate powder into a heated water bath to obtain a sodium alginate solution, and then adding gelatin after the sodium alginate is completely dissolved into a homogeneous liquid to obtain a sodium alginate-gelatin mixed system; After the gelatin in the sodium alginate-gelatin mixed system is completely dissolved, the temperature is lowered, and the genus quahog powder and the genus quahog residue are respectively added thereto, and after mixing, a genus quahog powder hydrogel precursor and a genus quahog residue hydrogel precursor are obtained; Ca was added to the hydrogel precursor of genkwa powder and genkwa residue, respectively. 2+ The solution becomes gelatinous, and the G units in the sodium alginate are exchanged with divalent calcium ions, so that the G units are cross-linked and stacked to form a network structure, thereby obtaining the genus quahog powder hydrogel and the genus quahog residue hydrogel.

2. The method for preparing the hydrogel of genkwa and genkwa residue according to claim 1, characterized in that: The mass concentration of genkwa root residue in the sodium alginate-gelatin mixed system is 0.05%-10%, and the mass concentration of genkwa root powder in the sodium alginate-gelatin mixed system is 0.05%-10%.

3. The method for preparing the hydrogel of genkwa and genkwa residue according to claim 1, characterized in that: The mass ratio of sodium alginate powder to the volume of water is 1 g to 2 g:100 mL.

4. The method for preparing the hydrogel of genkwa and genkwa residue according to claim 1, characterized in that: The mass ratio of gelatin to the volume of the sodium alginate solution is 1 g to 2 g:100 mL.

5. The method for preparing the hydrogel of genkwa and genkwa residue according to claim 1, characterized in that: The mass ratio of coriander root powder to water is 1g~2g:40mL~50mL.

6. The method for preparing the hydrogel of genkwa and genkwa residue according to claim 1, wherein Ca 2+ The mass concentration of the solution is 2% to 3%.

7. The method for preparing hydrogel of genkwa and genkwa residue according to claim 1, characterized in that: The freeze-drying temperature is -80°C to -70°C, and the freeze-drying time is 10h to 12h.

8. The method for preparing the hydrogel of genkwa and genkwa residue according to claim 1, characterized in that: The water bath temperature after heating is 75℃~80℃, and then cools down to 55℃~60℃.

9. A genus quahog powder and genus quahog residue hydrogel prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the genus quahog powder and genus quahog hydrogel as claimed in claim 9 as a composite material matrix in a fruit preservation material.

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