Plant silicon water for reducing uric acid and preparation method thereof

Abstract

This invention belongs to the field of food and health product technology, and particularly relates to a plant-based silicon water for lowering uric acid and its preparation method. The method includes: S1, pulverizing bamboo leaves to obtain an extract; S2, performing solid-liquid separation on the extract and collecting the liquid portion; S3, concentrating the liquid portion to obtain a concentrated solution; S4, filtering the concentrated solution using an ultrafiltration membrane to obtain the plant-based silicon water. This invention uses bamboo leaves as a single raw material and, through the combination of the process routes of this invention, directionally prepares a plant-based silicon water product with uric acid-lowering effects, achieving a clear correspondence between efficacy and specific plant source and preparation method. This invention uses a combination of cellulase and pectinase enzymatic hydrolysis combined with gradient temperature extraction to effectively improve the dissolution efficiency of active ingredients in bamboo leaves; low-temperature vacuum concentration maximizes the retention of heat-sensitive active substances; the obtained product is a clear liquid form, facilitating subsequent processing into functional product forms such as oral liquids.

Description

Technical Field

[0001] This invention belongs to the field of food and health product technology, and in particular relates to a plant-based silicon water that lowers uric acid and its preparation method. Background Technology

[0002] Uric acid is the end product of purine metabolism in the human body, mainly produced by xanthine oxidase catalyzing the formation of hypoxanthine and xanthine. A deficiency of uric acid oxidase in the human body prevents the further breakdown of uric acid into the more water-soluble allantoin. Therefore, when excessive uric acid is produced or its excretion is impaired, the concentration of uric acid in the blood rises, leading to hyperuricemia, which may subsequently cause gout, kidney stones, and kidney damage. Current uric acid-lowering products mainly rely on chemical drugs, such as allopurinol and febuxostat, xanthine oxidase inhibitors, which carry certain side effects with long-term use. Therefore, uric acid-lowering functional foods or health supplements derived from natural plants, with high safety profiles, and suitable for long-term consumption, are gradually becoming a research hotspot.

[0003] Bamboo leaves contain flavonoids, polysaccharides, amino acids, and silicon, exhibiting certain physiological activities. In existing technologies, extracts from bamboo leaves are primarily used for antioxidant and food preservation purposes. Extraction methods typically involve high-temperature decoction, alcohol extraction, macroporous resin purification, and spray drying, resulting in mostly solid powders. Targeted preparation methods for lowering uric acid are rarely reported. Some existing technologies disclose uric acid-lowering compositions containing metasilicic acid or silicon, but these compositions are generally complex systems composed of multiple plant ingredients, with complex sources of active ingredients and correspondingly cumbersome preparation processes. It is difficult to clearly define the correlation between efficacy and single plant source or specific preparation method.

[0004] Therefore, there is still a need for a uric acid-lowering plant-based silicon aquatic product and its preparation method that uses bamboo leaves as a single raw material and is prepared through a reasonable process. Summary of the Invention

[0005] The main objective of this invention is to provide a plant-based silicon water for lowering uric acid and its preparation method, so as to overcome the shortcomings of the prior art.

[0006] To achieve the aforementioned objectives, the technical solution adopted by this invention includes: According to a first aspect of the present invention, a method for preparing uric acid-lowering plant-based silicon water is provided, comprising the following steps: S1. After pulverizing bamboo leaves, add water, cellulase, and pectinase. Enzymatically hydrolyze at 40℃~60℃ for 0.5~2 hours, then heat to 85℃~95℃ for 1~3 hours to obtain the extract. This step includes two stages: pre-pulverization treatment and staged extraction. The purpose of pulverization is to reduce the particle size of the bamboo leaf raw material and increase its contact area with the extraction solvent, which is beneficial to the dissolution of active ingredients during subsequent enzymatic hydrolysis and extraction. The enzymatic hydrolysis stage uses a combination of cellulase and pectinase. The main structural components of bamboo leaf cell walls include polysaccharides such as cellulose and pectin, which constitute the physical barrier for the dissolution of active substances. Cellulase can hydrolyze cellulose chains and destroy the skeletal structure of the cell wall; pectinase can degrade pectin components, further loosening the cell wall. The synergistic effect of the two enzymes can effectively break down the cell wall and promote the release of the target active ingredients within the cell. The enzymatic hydrolysis temperature is controlled between 40℃ and 60℃. This temperature range accommodates the optimal activity range of both cellulase and pectinase, ensuring hydrolysis efficiency while preventing excessively high temperatures from causing enzyme protein denaturation and inactivation. The hydrolysis time is 0.5 to 2 hours, which can be adjusted according to the actual situation such as raw material particle size and enzyme dosage. After enzymatic hydrolysis, the system is heated to 85℃ to 95℃ for hot water extraction. Heating to this temperature range denatures residual enzyme proteins, terminating the enzymatic hydrolysis reaction. Furthermore, hot water, as a polar solvent, accelerates mass transfer at higher temperatures, further dissolving soluble silicon, flavonoid glycosides, and other small molecule active substances remaining in the bamboo leaf tissue. The extraction time is 1 to 3 hours, balancing extraction efficiency and production efficiency. This step employs a phased operation method of "compound enzymatic hydrolysis pretreatment - heated hot water extraction". First, the cell wall is broken by enzymatic hydrolysis under mild conditions, and then the dissolution is enhanced by high temperature conditions. Compared with single high-temperature decoction or single enzymatic hydrolysis treatment, this method is beneficial to improve the extraction yield of active ingredients and the activity intensity of the extract.

[0007] S2. Perform solid-liquid separation on the extract and collect the liquid portion. The extract contains dissolved target components and undissolved bamboo leaf residue. The purpose of solid-liquid separation is to separate the residue from the liquid portion containing the active ingredients. Applicable solid-liquid separation methods include, but are not limited to, conventional methods such as centrifugation, plate and frame filtration, and vacuum filtration. After solid-liquid separation, the collected liquid portion is the feed liquid for subsequent concentration and membrane filtration operations. This step operates under mild conditions and will not significantly affect the dissolved active ingredients in the extract.

[0008] S3. The liquid portion is concentrated to 1 / 20 to 1 / 5 of its original volume under conditions of 50℃~70℃ and a vacuum of -0.08MPa~-0.1MPa to obtain a concentrated solution. The liquid portion after solid-liquid separation has a large volume and a low concentration of active ingredients, making it unsuitable for direct use in subsequent membrane filtration or product filling; therefore, concentration is necessary. This step employs reduced-pressure concentration, lowering the boiling point of the liquid under vacuum conditions so that it boils and evaporates water at a relatively low temperature of 50℃~70℃, achieving the concentration objective. A vacuum range of -0.08MPa~-0.1MPa is used to achieve a significant boiling point reduction. The concentration endpoint is controlled at 1 / 20 to 1 / 5 of the original volume, i.e., a concentration factor of 5 to 20 times, ensuring that the concentration of active ingredients in the concentrated solution reaches a suitable range for subsequent ultrafiltration. Low-temperature concentration avoids the damage to heat-sensitive active ingredients caused by prolonged high-temperature heating required for atmospheric pressure evaporation, which is beneficial for preserving the active substances in the extract. At the same time, concentration to a certain factor can reduce the material volume of subsequent ultrafiltration treatment and improve membrane filtration efficiency.

[0009] S4. Filter the concentrated liquid using an ultrafiltration membrane with a molecular weight cutoff of 5kDa to 10kDa, and collect the permeate to obtain the plant-based silicon water. Ultrafiltration is a pressure-driven membrane separation technology that utilizes the sieving effect of membrane pore size to separate substances of different molecular weights. This step uses an ultrafiltration membrane with a molecular weight cutoff of 5kDa to 10kDa, meaning the pore size is characterized by the membrane's ability to retain more than 90% of the standard substance of that molecular weight. In addition to the target active small molecules, the bamboo leaf extract concentrate also contains large molecules such as plant proteins, polysaccharides, and tannins. The presence of these large molecules may affect the product's clarity, stability, and taste. After treatment with an ultrafiltration membrane with a molecular weight cutoff of 5kDa to 10kDa, large molecular impurities with molecular weights greater than the cutoff are retained, while smaller molecular weight active ingredients (including soluble silicon, flavonoid aglycones, and small molecule organic acids) permeate through the membrane pores with the solvent into the permeate. The collected permeate is the final plant-based silicon water product.

[0010] Compared with the prior art, the advantages of the present invention include: This invention provides a plant-based silicon water for lowering uric acid and its preparation method. Using bamboo leaves as the raw material, this invention employs a combination of processes to directionally prepare a plant-based silicon water product with uric acid-lowering effects, achieving a clear correspondence between efficacy and specific plant source and preparation method. This invention utilizes a combination of cellulase and pectinase enzymatic hydrolysis with gradient temperature extraction, effectively improving the dissolution efficiency of active ingredients in bamboo leaves; low-temperature vacuum concentration maximizes the retention of heat-sensitive active substances; and a 5kDa~10kDa molecular weight cutoff ultrafiltration membrane achieves relative enrichment of active molecular groups and product stabilization. The resulting product is a clear liquid with excellent sensory quality, facilitating subsequent processing into functional products such as oral liquids. Verification using a zebrafish hyperuricemia model shows that the plant-based silicon water of this invention exhibits a statistically significant uric acid-lowering effect at a final concentration of 1% by volume, providing experimental evidence for the application of this product in functional foods or health products that assist in lowering blood uric acid. Attached Figure Description

[0011] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a graph showing the uric acid-lowering efficacy of the plant-based silicon water prepared in Example 1 of this invention, using a zebrafish hyperuricemia model. Detailed Implementation

[0012] In view of the shortcomings of the prior art, the inventors of this invention, through long-term research and extensive practice, have proposed the technical solution of this invention. The following will further explain and illustrate this technical solution, its implementation process, and its principles.

[0013] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0014] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials used in the following embodiments are commercially available.

[0015] This invention provides a method for preparing uric acid-lowering plant-based silicon water, comprising the following steps: (1) After crushing the bamboo leaves, add water, cellulase, and pectinase, and enzymatically hydrolyze at 40℃~60℃ for 0.5~2 hours, then heat to 85℃~95℃ for 1~3 hours to obtain the extract. The combined use of cellulase and pectinase can effectively degrade the cellulose and pectin components in the cell walls of bamboo leaves and promote the release of intracellular active substances. Enzymatic hydrolysis is carried out under mild conditions of 40℃~60℃, which can maintain enzyme activity while avoiding the destruction of target components by high temperature. After enzymatic hydrolysis, the system is heated to 85℃~95℃ for hot water extraction, which uses high temperature to enhance mass transfer and further dissolve the soluble components remaining in the plant tissue.

[0016] (2) Perform solid-liquid separation on the extract and collect the liquid fraction; solid-liquid separation can be performed by centrifugation or plate and frame filtration. The purpose of solid-liquid separation is to remove bamboo leaf residue and obtain a clear or slightly turbid liquid fraction, which is convenient for subsequent concentration and membrane filtration operations.

[0017] (3) The liquid portion is concentrated to 1 / 20 to 1 / 5 of its original volume under the conditions of 50℃ to 70℃ and vacuum of -0.08MPa to -0.1MPa to obtain a concentrated solution; the concentration conditions are 50℃ to 70℃ and vacuum of -0.08MPa to -0.1MPa. Concentration under reduced pressure within this temperature and vacuum range can efficiently remove moisture at lower temperatures, shorten the heating time of the material, and reduce the loss of heat-sensitive active ingredients. Concentrating to 1 / 20 to 1 / 5 of the original volume yields a suitable concentration range for subsequent membrane filtration.

[0018] (4) The concentrate is filtered through an ultrafiltration membrane with a molecular weight cutoff of 5kDa to 10kDa, and the permeate is collected to obtain the plant silicate water. The molecular weight cutoff of the ultrafiltration membrane is selected to be 5kDa to 10kDa. Using an ultrafiltration membrane in this molecular weight range can remove large molecular impurities such as polysaccharides and proteins, while retaining smaller molecular weight active ingredients, thereby obtaining a plant silicate water permeate with relatively rich effective ingredients and stable physicochemical properties. The soluble silicon content in the obtained plant silicate water is preferably in the range of 20mg / L to 150mg / L.

[0019] In the above preparation method, the bamboo leaves used as raw material are preferably moso bamboo leaves, and their moisture content is no more than 12%. Using dried bamboo leaves with low moisture content is beneficial for pulverization and ensuring batch stability of extraction efficiency.

[0020] In some embodiments, after step (4) above, the step of filling and sterilizing the permeate may be included. The sterilization conditions are preferably sterilization at 121°C for 15 to 20 minutes to obtain a liquid product or intermediate product that can be stored for a long time.

[0021] Secondly, the present invention provides a plant-based silicon water for lowering uric acid, which is prepared by any of the above-described preparation methods.

[0022] Thirdly, the present invention provides an oral liquid preparation of uric acid-lowering plant silicon water, comprising the aforementioned plant silicon water and food-acceptable excipients. The oral liquid preparation may be available in vials of 100mL to 150mL, wherein the volume content of the plant silicon water is not less than 95%.

[0023] Fourthly, the present invention provides the application of the above-mentioned uric acid-lowering plant silicon water in the preparation of food or health products that help lower blood uric acid.

[0024] To better understand the technical solution of the present invention, the following detailed discussion is provided in conjunction with specific embodiments.

[0025] Example 1

[0026] This embodiment provides a method for preparing uric acid-lowering plant-based silicon water, including the following steps: Step (1): Take dried bamboo leaves with a moisture content of 10.5% and crush them through a 30-mesh sieve. Weigh 100g of bamboo leaf powder, add 1000mL of purified water, stir well, then add 0.4g of cellulase and 0.2g of pectinase, and enzymatically hydrolyze at 40℃ for 0.5 hours. After enzymatic hydrolysis, raise the temperature of the system to 85℃ and continue extraction for 1 hour to obtain the extract.

[0027] Step (2): The extract is separated into solid and liquid by plate and frame filtration, and about 920 mL of filtrate is collected.

[0028] Step (3): Place the filtrate in a rotary evaporator and concentrate it under reduced pressure at a temperature of 50℃ and a vacuum of -0.08MPa until it is reduced to 1 / 5 of the original volume, i.e., about 184mL, to obtain the concentrated solution.

[0029] Step (4): Filter the concentrate using an ultrafiltration membrane with a molecular weight cutoff of 5 kDa at an operating pressure of 0.15 MPa. Collect approximately 165 mL of permeate to obtain the plant silicon aquatic product.

[0030] The soluble silicon content in the plant silicon water obtained in this embodiment was found to be 22.5 mg / L.

[0031] The permeate was filled into glass bottles, sealed, and sterilized at 121°C for 15 minutes to obtain the finished plant silicon water oral liquid.

[0032] The uric acid-lowering efficacy of the aforementioned plant-based silicon water was tested using a zebrafish hyperuricemia model. The testing was conducted according to internal laboratory methods, referring to the relevant requirements of GB / T39649-2020 and GB / T13267-1991. Wild AB strain zebrafish (5 days post-fertilization) were used as experimental subjects. The experiment included a blank control group, a control group, a positive control group, and a sample treatment group. Xanthine and potassium oxonate were added to the control group, positive control group, and sample treatment group to construct the hyperuricemia model. The sample treatment group, along with xanthine and potassium oxonate, was simultaneously treated with the aforementioned plant-based silicon water at a final concentration of 1% by volume. Allopurinol was used instead of the sample in the positive control group. After culture treatment, zebrafish tissue homogenates were collected, and uric acid levels were measured using a uric acid analyzer. Experimental data were statistically analyzed using SPSS 26 software, and normally distributed data are expressed as mean ± standard deviation.

[0033] Test results as follows Figure 1 As shown in the figure: compared with the blank group, the p-value was 0.0045; compared with the positive group, the p-value was 0.0011; compared with the sample group, the p-value was 0.0404; *: P < 0.05; **: P < 0.01; ***: P < 0.001; the more *, the smaller the p-value, indicating a more significant difference. Specific values ​​are shown in Table 1. The average uric acid level in the blank control group was 400.33 ± 1.70 μmol / L, while the average uric acid level in the control group significantly increased to 417.00 ± 3.74 μmol / L (p = 0.0045), indicating successful modeling. The average uric acid level in the positive control group decreased to 374.33 ± 6.24 μmol / L, showing a highly significant difference compared to the control group (p = 0.0011). The average uric acid level in the sample treatment group was 408.67 ± 1.25 μmol / L, which was statistically significant compared with the control group (p = 0.0404), and the improvement rate was (417.00–408.67) ÷ 417.00 × 100% = 1.99%.

[0034] The above results indicate that the plant-based silicon water prepared by the method of the present invention has a uric acid-lowering effect in the zebrafish hyperuricemia model, and its improvement rate on the uric acid value of the model zebrafish is not less than 1.9%.

[0035] Table 1. Uric acid levels in zebrafish (μmol / L)

[0036] Example 2

[0037] This embodiment provides a method for preparing uric acid-lowering plant-based silicon water, including the following steps: Step (1): Take dried bamboo leaves with a moisture content of 9.8% and crush them through a 30-mesh sieve. Weigh 100g of bamboo leaf powder, add 1000mL of purified water, stir well, then add 0.5g of cellulase and 0.3g of pectinase, and enzymatically hydrolyze at 50℃ for 1.2 hours. After enzymatic hydrolysis, raise the temperature of the system to 90℃ and continue extraction for 2 hours to obtain the extract.

[0038] Step (2): The extract was centrifuged (4500 rpm, 15 minutes) to separate solids and liquids, and about 910 mL of supernatant was collected.

[0039] Step (3): Place the supernatant in a rotary evaporator and concentrate it under reduced pressure at a temperature of 60℃ and a vacuum of -0.09MPa until it is reduced to 1 / 10 of the original volume, i.e., about 91mL, to obtain the concentrated liquid.

[0040] Step (4): Filter the concentrate using an ultrafiltration membrane with a molecular weight cutoff of 8 kDa at an operating pressure of 0.15 MPa. Collect about 80 mL of permeate to obtain the plant silicon aquatic product.

[0041] The soluble silicon content in the plant silicon water obtained in this embodiment was found to be 45.2 mg / L.

[0042] The permeate was filled into glass bottles, sealed, and sterilized at 121°C for 18 minutes to obtain the finished plant silicon water oral liquid.

[0043] The efficacy was tested according to the detection method in Example 1. Plant silicon water of this example was added at a final volume ratio of 1%. The uric acid value of the model zebrafish was 409.12±1.58μmol / L, and the uric acid value of the control group was 417.00±3.74μmol / L. The uric acid improvement rate was 1.89%, which was statistically significant compared with the control group (p<0.05).

[0044] Example 3

[0045] This embodiment provides a method for preparing uric acid-lowering plant-based silicon water, including the following steps: Step (1): Take dried bamboo leaves with a moisture content of 11.8% and crush them through a 30-mesh sieve. Weigh 100g of bamboo leaf powder, add 1000mL of purified water, stir well, then add 0.6g of cellulase and 0.4g of pectinase, and enzymatically hydrolyze at 60℃ for 2 hours. After enzymatic hydrolysis, raise the temperature of the system to 95℃ and continue extraction for 3 hours to obtain the extract.

[0046] Step (2): The extract is separated into solid and liquid by plate and frame filtration, and about 900 mL of filtrate is collected.

[0047] Step (3): Place the filtrate in a rotary evaporator and concentrate it under reduced pressure at a temperature of 70℃ and a vacuum of -0.1MPa until it is reduced to 1 / 20 of the original volume, i.e., about 45mL, to obtain the concentrated solution.

[0048] Step (4): Filter the concentrate using an ultrafiltration membrane with a molecular weight cutoff of 10 kDa at an operating pressure of 0.15 MPa. Collect about 38 mL of permeate to obtain the plant silicon aquatic product.

[0049] The soluble silicon content in the plant silicon water obtained in this embodiment was found to be 142.8 mg / L.

[0050] The permeate was filled into glass bottles, sealed, and sterilized at 121°C for 20 minutes to obtain the finished plant silicon water oral liquid.

[0051] The efficacy was tested according to the detection method in Example 1. The plant silicon water of this example was added at a final volume ratio of 1%. The uric acid value of the model zebrafish was 407.85±1.67μmol / L, and the uric acid value of the control group was 417.00±3.74μmol / L. The uric acid improvement rate was 2.19%, which was statistically significant compared with the control group (p<0.05).

[0052] The above three examples demonstrate that plant-based silicon aquatic products with soluble silicon content in the range of 20 mg / L to 150 mg / L can be successfully prepared, and all of them show a uric acid improvement rate of not less than 1.9% in the zebrafish hyperuricemia model, verifying the technical feasibility and efficacy reliability of the limited numerical range.

[0053] Comparative Example 1 The pretreatment with combined enzymatic hydrolysis using cellulase and pectinase was not performed; the remaining steps were the same as in Example 2 of this invention. Specifically, 100g of dried bamboo leaves with a moisture content of 9.8% were taken, pulverized to pass through a 30-mesh sieve, and 1000mL of purified water were added. No enzyme preparations were added, and the mixture was directly heated to 90℃ and decocted for 3.2 hours (the total extraction time was consistent with the total time of 1.2 hours of enzymatic hydrolysis plus 2 hours of soaking in Example 2), yielding the extract. Subsequently, the extract was subjected to centrifugal solid-liquid separation, concentrated to 1 / 10 of its original volume at 60℃ / -0.09MPa, filtered through an 8kDa ultrafiltration membrane, and the permeate was collected and sterilized at 121℃ for 18 minutes to obtain the comparative plant silicon aquatic product.

[0054] Comparative Example 2 The method involves pretreatment with only cellulase, without the addition of pectinase, and the remaining steps are the same as in Example 1 of this invention. Specifically, 100g of dried bamboo leaves with a moisture content of 9.8% are taken, pulverized to pass through a 30-mesh sieve, 1000mL of purified water is added, and 0.5g of cellulase (without pectinase) is added. The mixture is enzymatically hydrolyzed at 50℃ for 1.2 hours, then heated to 90℃ for extraction for 2 hours. Subsequent steps are the same as in Example 1.

[0055] Detection methods and indicators: The uric acid-lowering efficacy of the product of Example 1 (compound enzymatic hydrolysis), the product of Comparative Example 1 (no enzymatic hydrolysis), and the product of Comparative Example 2 (single cellulose enzymatic hydrolysis) of this invention was tested according to the zebrafish experimental method described above. Each product was treated with a final concentration of 1% by volume. The soluble silicon content of the three products was also determined. The test results are shown in Table 2. Table 2

[0056] Results analysis: The soluble silicon content of the product obtained in Comparative Example 1 was only 11.8 mg / L, which was significantly lower than 45.2 mg / L in Example 1; the uric acid improvement rate was only 0.52%, and there was no statistically significant difference compared with the model control group (p=0.3821>0.05). This indicates that without enzymatic hydrolysis, direct decoction of bamboo leaves resulted in insufficient cell wall disruption, low dissolution efficiency of intracellular active ingredients, and the product did not have a significant uric acid-lowering effect.

[0057] The soluble silicon content of the product obtained in Comparative Example 2 (cellulosic hydrolysis only) was 28.3 mg / L, lower than that in Example 1; the uric acid improvement rate was 1.12%, which was not statistically significant compared with the model control group (p=0.1576>0.05). This indicates that the use of cellulase alone without the synergistic effect of pectinase resulted in insufficient degradation of pectin components in the cell walls of bamboo leaves, incomplete release of active ingredients, and difficulty in achieving a statistically significant uric acid-lowering effect. Example 1 of this invention uses a combination of cellulase and pectinase for enzymatic hydrolysis. The two enzymes work together to break the cell walls, effectively promoting the dissolution of active silicon and other small molecule active ingredients in bamboo leaves. The soluble silicon content of the product reached 45.2 mg / L, and the uric acid improvement rate reached 1.99%, which was statistically significant compared with the model control group (p=0.0404<0.05). This comparative experiment fully demonstrates that the combined enzymatic hydrolysis pretreatment in step (1) of this invention is one of the key technical features to ensure the uric acid-lowering efficacy of the product.

[0058] Comparative Example 3 The high-temperature concentration under normal pressure is used instead of the low-temperature vacuum concentration, and the remaining steps are the same as in Example 1 of this invention. Specifically, steps (1) and (2) are the same as in Example 1. In step (3), the supernatant is heated to boiling under normal pressure and evaporated to 1 / 10 of the original volume. In step (4), an 8kDa ultrafiltration membrane is used for filtration to obtain the comparative product.

[0059] Comparative Example 4 An ultrafiltration membrane with a molecular weight cutoff exceeding the scope of this invention was used, and the remaining steps were the same as in Example 1 of this invention. Specifically, steps (1) to (3) were the same as in Example 2, and in step (4), an ultrafiltration membrane with a molecular weight cutoff of 30 kDa was used for filtration, the permeate was collected, and a comparative product was obtained.

[0060] Detection methods and indicators: The uric acid-lowering efficacy of the products of Example 2 (low-temperature vacuum concentration + 8kDa ultrafiltration), Comparative Example 3 (normal pressure high-temperature concentration + 8kDa ultrafiltration), and Comparative Example 4 (low-temperature vacuum concentration + 30kDa ultrafiltration) was tested according to the zebrafish experimental method described in Example 1. Each product was treated with a final concentration of 1% by volume. The sensory properties (color, clarity) and soluble silicon content of each product were also compared. The test results are shown in Table 3. Table 3

[0061] Results analysis: Comparative Example 3, using atmospheric pressure and high-temperature concentration, resulted in a product with a darker yellowish-brown color and slight turbidity. Its soluble silicon content was 42.6 mg / L, similar to Example 1, but the uric acid improvement rate was only 0.87%, with no statistically significant difference from the control group (p=0.2458>0.05). This indicates that although atmospheric pressure and high-temperature concentration did not significantly affect the soluble silicon content, during prolonged high-temperature boiling, the heat-sensitive active ingredients in the extract underwent degradation or denaturation, leading to a significant decrease in the product's uric acid-lowering efficacy. This invention uses low-temperature vacuum concentration at 50℃~70℃, effectively avoiding the loss of heat-sensitive active ingredients.

[0062] The above descriptions are merely some embodiments of the present invention. It should be noted that those skilled in the art can make other modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A method for preparing uric acid-lowering plant-based silicon water, characterized in that, Includes the following steps: S1. After crushing the bamboo leaves, add water, cellulase and pectinase, and enzymatically hydrolyze at 40℃~60℃ for 0.5~2 hours, then heat to 85℃~95℃ for 1~3 hours to extract the extract. S2. Perform solid-liquid separation on the extract and collect the liquid portion; S3. The liquid portion is concentrated to 1 / 20 to 1 / 5 of its original volume under conditions of 50℃~70℃ and vacuum degree of -0.08MPa~-0.1MPa to obtain a concentrated solution; S4. Filter the concentrated liquid using an ultrafiltration membrane with a molecular weight cutoff of 5kDa~10kDa, collect the permeate, and obtain the plant silicon water.

2. The preparation method according to claim 1, characterized in that, The bamboo leaves mentioned in step S1 are moso bamboo leaves, and their moisture content is no more than 12%.

3. The preparation method according to claim 1, characterized in that, The solid-liquid separation method described in step S2 is centrifugation or plate and frame filtration.

4. The preparation method according to claim 1, characterized in that, The soluble silicon content in the plant silica water obtained in step S4 is 20 mg / L to 150 mg / L.

5. The preparation method according to claim 1, characterized in that, Step S4 is followed by filling and sterilizing the permeate, wherein the sterilization conditions are sterilization at 121°C for 15-20 minutes.

6. A plant-based silicon water for lowering uric acid, characterized in that, It is prepared by any one of claims 1-5.

7. The uric acid-lowering plant-based silicon water according to claim 6, characterized in that, In a zebrafish hyperuricemia model induced by potassium oxonate and xanthine, when the plant silicon water was added at a final concentration of 1% by volume, the uric acid value of the model zebrafish was statistically significantly lower than that of the control group without the addition of the plant silicon water.

8. The uric acid-lowering plant-based silicon water according to claim 7, characterized in that, Its improvement rate on the uric acid value of model zebrafish is no less than 1.9%, and the improvement rate is calculated by the following formula: Improvement rate = (average uric acid value of control group - average uric acid value of plant silicon water treatment group) ÷ average uric acid value of control group × 100%.

9. An oral liquid preparation of plant-based silicon water for lowering uric acid, characterized in that, It comprises any one of the plant-based silicon waters according to claims 6-8 and food-acceptable additives.

10. The use of the uric acid-lowering plant silica water according to any one of claims 6-8 in the preparation of food or health products that help lower blood uric acid.

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