Functional food composition for preventing or improving diabetes or kidney diseases comprising natural materials

Abstract

The present invention relates to a health functional food composition for the prevention or improvement of diabetes or kidney disease, wherein the health functional food composition is characterized by optimizing the content of each of various active ingredients, such as chitosan, silkworm powder, calcium carbonate, ginkgo leaf extract, and magnesium oxide, and the extraction conditions of the complex extract, and confirming a significant effect in the prevention or improvement of diabetes or kidney disease depending on the combination of chitosan, silkworm powder, and ginkgo leaf extract.

Description

Technology Field

[0001] The present invention relates to a health functional food composition for the prevention or improvement of diabetes or kidney disease. Background Technology

[0003] Diabetes and kidney disease are chronic conditions with steadily increasing prevalence both domestically and internationally, and are recognized as diseases requiring essential long-term management alongside lifestyle modifications and medication. As these diseases can lead to various systemic complications due to a breakdown in physiological balance—such as blood sugar control or the maintenance of kidney function—there is a growing need for supportive approaches for early prevention and improvement.

[0004] Accordingly, as an attempt to alleviate the burden of disease through non-drug methods, various natural product-based compositions in the form of health functional foods or dietary supplements are being actively developed. In particular, there is increasing interest in complex compositions that consider bioavailability and synergistic effects of complex formulations. Research on these compositions is expanding in the direction of maximizing functionality through the combined use of auxiliary ingredients that can contribute to metabolism in the body, in addition to the main functional ingredients.

[0005] Meanwhile, chitosan is a naturally derived polymer with potential for use in lipid metabolism and the regulation of ion exchange within the body, and silkworm powder has traditionally been used in diets, with some studies reported regarding its potential in relation to glucose metabolism. Additionally, ginkgo leaf extract is utilized in various health functional foods, focusing on improving blood circulation and enhancing memory, and is being considered as a natural material capable of playing an auxiliary role within the composition. Accordingly, it is expected that applying these ingredients in combination will overcome the limitations of single components and secure the potential for various physiological improvements.

[0006] However, many health functional food compositions proposed to date have limitations, such as insufficient control of the content of each active ingredient or optimization of extraction conditions, or a lack of scientific verification regarding synergistic effects resulting from interactions between compositions. In particular, compositions aimed at simultaneously improving complex functions for diabetes and kidney disease fall into a field that has not been sufficiently reviewed, either technically or clinically.

[0007] Against this backdrop, the inventors precisely designed the mixing ratios of each component and the extraction conditions of the complex extract, centering on chitosan, silkworm powder, and ginkgo leaf extract, and additionally incorporated functional components such as calcium carbonate, magnesium oxide, vitamin D3, and zinc oxide to realize a health functional food composition capable of comprehensively addressing the prevention and improvement of diabetes and kidney disease. The problem to be solved

[0009] One aspect provides a health functional food composition for preventing or improving diabetes or kidney disease comprising chitosan, silkworm powder, calcium carbonate, ginkgo leaf extract, and magnesium oxide, further comprising vitamin B12, magnesium stearate, crystalline cellulose, vitamin D3, zinc oxide, a mixture of lactose, pectin, and flavoring, and glucosamine hydrochloride.

[0010] Another aspect provides a health functional food composition for preventing or improving diabetes or kidney disease comprising chitosan, silkworm powder, calcium carbonate, ginkgo leaf extract, and magnesium oxide, further comprising vitamin B12, magnesium stearate, crystalline cellulose, vitamin D3, zinc oxide, a mixture of lactose, pectin, and flavoring, and glucosamine hydrochloride, for lowering blood sugar or inhibiting advanced glycation end products. means of solving the problem

[0012] One aspect is to provide a health functional food composition for the prevention or improvement of diabetes or kidney disease.

[0013] Specifically, one aspect provides a health functional food composition for preventing or improving diabetes or kidney disease comprising chitosan, silkworm powder, calcium carbonate, ginkgo leaf extract, and magnesium oxide, further comprising vitamin B12, magnesium stearate, crystalline cellulose, vitamin D3, zinc oxide, a mixture of lactose, pectin, and flavoring, and glucosamine hydrochloride.

[0014] In this specification, the term "chitosan" refers to a natural polymer material produced from chitin through a deacetylation reaction, and may mean a cationic polysaccharide composed mainly of β-(1→4)-linked D-glucosamine residues. Chitosan is known for its physical properties as a dietary fiber and physiological activities such as metal ion adsorption capacity and lipid adsorption.

[0015] In this specification, the term "silkworm powder" may refer to a natural raw material in powder form prepared by grinding the dried body of *Bombyx mori*. Silkworm powder contains protein, amino acids, and various vitamins and minerals, and is known to have traditionally been used as a protein supplement and for health promotion purposes.

[0016] In this specification, the term "Ginkgo leaf extract" refers to a concentrate or dried product prepared by extracting the dried leaves of the Ginkgo biloba L. with water or a water-soluble organic solvent, which is known to have antioxidant activity and blood flow improvement effects, with flavonoid and terpenoid series components as its main components.

[0017] In this specification, the term "calcium carbonate" refers to an inorganic compound having the chemical formula CaCO3, which may be a white powder-form substance produced from natural minerals or through a synthetic process. Calcium carbonate is widely used as a calcium supplement for the human body and can be utilized for various purposes, such as as a stomach acid neutralizer.

[0018] In this specification, the term "magnesium oxide" refers to an inorganic compound having the chemical formula MgO, which may be a white or grayish-white powder produced primarily through a high-temperature calcination process. Magnesium oxide is used as a source of magnesium and can generally be utilized as a stomach acid neutralizer and laxative.

[0019] Specifically, the above health functional food composition may comprise 43 to 45 parts by weight of chitosan, 16 to 18 parts by weight of silkworm powder, 14 to 16 parts by weight of calcium carbonate, 8 to 10 parts by weight of ginkgo leaf extract, 4.5 to 6.5 parts by weight of magnesium oxide, 1 to 3 parts by weight of vitamin B12, 1 to 3 parts by weight of magnesium stearate, 1 to 3 parts by weight of crystalline cellulose, 0.5 to 1.5 parts by weight of vitamin D3, 0.5 to 1.5 parts by weight of zinc oxide, 0.5 to 1.5 parts by weight of a lactose-pectin-flavoring mixture, and 0.1 to 1.0 parts by weight of glucosamine hydrochloride.

[0020] More specifically, the above health functional food composition may comprise 44.0 parts by weight of chitosan, 17.0 parts by weight of silkworm powder, 15.0 parts by weight of calcium carbonate, 9.0 parts by weight of ginkgo leaf extract, 5.6 parts by weight of magnesium oxide, 2.0 parts by weight of vitamin B12, 2.0 parts by weight of magnesium stearate, 2.0 parts by weight of crystalline cellulose, 1.0 parts by weight of vitamin D3, 1.0 parts by weight of zinc oxide, 1.0 parts by weight of a lactose-pectin-flavoring mixture, and 0.4 parts by weight of glucosamine hydrochloride.

[0021] The above chitosan:silkworm powder:ginkgo leaf extract may be included as a complex extract powder in a weight ratio of 4.8~5.0:1.8~2.0:1.

[0022] In the above health functional food composition, the complex extract of chitosan, silkworm powder and / or ginkgo leaf extract may be extracted under conditions of 55℃ to 65℃, 1.5 hours to 2.5 hours, and 400 to 600 rpm.

[0023] If the above extraction conditions are exceeded, there is a possibility that components within the composition may decompose during short-term extraction at high temperatures, and it may be difficult to produce a uniform extract due to insufficient stirring.

[0024] The extraction solvent of the above-mentioned complex extract may be purified water, an aqueous ethanol solution, etc., but is not particularly limited thereto. More specifically, the extraction solvent is characterized as being purified water. If the extraction solvent is an aqueous ethanol solution or if the ethanol concentration is high relative to the purified water, there may be problems such as reduced extraction of water-soluble components and precipitation of chitosan.

[0025] In the above health functional food composition, the chitosan may be dissolved under conditions of an acetic acid concentration of 0.8 to 1.5% (w / v), a solvent volume of 250 mL to 300 mL (based on 44 g / 0 of chitosan), a stirring speed of 450 to 600 rpm, and a stirring time of 2.5 to 4 hours.

[0026] If the above conditions are exceeded, there is a risk that the solubility of chitosan will decrease or the viscosity of the solution will increase, leading to gelation, and there may be problems such as uneven dissolution or insufficient dissolution of the polymer.

[0027] In the pulverization of the above complex extract, the pulverization may be performed at an inlet temperature of 140°C to 165°C and an outlet temperature of 75°C to 85°C, and if the above range is exceeded, there may be a problem of loss of components or thermal decomposition.

[0028] In one embodiment, 1,000 mL of purified water was added to domestically produced dried ginkgo leaves (moisture content 10% or less) to set the solvent ratio to approximately 10 times the solid content, and the mixture was stirred and extracted in a 60°C water bath for 2 hours (based on 500 rpm). Subsequently, the extract was filtered first using a 100 mesh stainless steel filter and concentrated using a vacuum concentrator (Rotary evaporator, 50°C, 200 mbar) to remove the solvent. The concentration was set to end when the solid content of the extract reached approximately 15% (w / w), and a homogeneous ginkgo leaf extract was obtained by checking the viscosity and color (brown viscous liquid) after the concentration was finished.

[0029] Subsequently, 17.0 g of silkworm powder and an amount corresponding to 9.0 g of the solid content of the prepared ginkgo leaf extract were weighed and added to 100 mL of purified water, followed by stirring and extraction in a 60°C water bath for 2 hours. After extraction, the mixture was filtered through a 100 mesh filter to remove suspended solids. Next, 44.0 g of chitosan was slowly added to a 1% aqueous acetic acid solution (total volume 300 mL) while stirring at 500 rpm for at least 3 hours to completely dissolve it, after which the silkworm / ginkgo leaf extract filtrate prepared above was added and mixed homogeneously. The mixture was concentrated to approximately one-third of its original volume using a vacuum concentrator (at 50°C under reduced pressure), and the concentrated complex extract was powdered using a spray dryer (dual fluid nozzle type, inlet temperature 160°C, outlet temperature 80°C) to obtain the complex extract powder.

[0030] The above-mentioned diabetes may be type 1 diabetes, type 2 diabetes, impaired fasting glucose, or impaired glucose tolerance, but is not specifically limited thereto.

[0031] In addition, the above-mentioned kidney disease may be one or more selected from the group consisting of chronic kidney disease, acute renal injury, glomerulonephritis, renal inflammation, diabetic nephropathy, and nephrotic syndrome, but is not particularly limited thereto.

[0032] A composition according to one aspect can exhibit the effect of preventing or improving AGEs-RAGE-mediated inflammatory responses and kidney tissue damage caused by oxidative stress by suppressing a rapid rise in blood sugar after a meal and suppressing the formation of AGEs.

[0033] A composition according to one aspect may be characterized by inhibiting α-glucosidase activity. The term "α-glucosidase" refers to an enzyme that breaks down polysaccharides into monosaccharides in the small intestine and may refer to a major enzyme involved in postprandial hyperglycemia.

[0034] In one embodiment, it was confirmed that a composition in which the content ratio of complex extract powder, calcium carbonate, and other active ingredients, as well as extraction conditions, were all optimized, inhibited α-glucosidase activity to a significant level, thereby being effective in suppressing blood glucose levels and preventing or improving diabetes.

[0035] In addition, a composition according to one aspect may be characterized by inhibiting the formation of Advanced Glycation End Products (AGEs). The term "Advanced Glycation End Products (AGEs)" refers to irreversible glycation products formed by the non-enzymatic reaction of proteins, lipids, or nucleic acids with sugars, which can cause tissue damage and inflammatory responses if accumulated in the body.

[0036] In one embodiment, a composition in which the content ratio of complex extract powder, calcium carbonate, and other active ingredients as well as extraction conditions were all optimized was found to have the highest inhibition rate of AGEs formation, and from this, it was confirmed that the composition is effective in preventing or improving kidney disease by alleviating kidney tissue damage caused by AGEs-RAGE-mediated inflammatory response and oxidative stress.

[0037] In this specification, the term "health functional food" refers to a food manufactured or processed by methods such as extraction, concentration, purification, or mixing of specific ingredients contained in food ingredients, or using specific ingredients as raw materials for the purpose of health supplementation, and may mean a food designed and processed to fully exert biological regulatory functions on the body, such as biological defense, regulation of biological rhythms, prevention and recovery from disease, through said ingredients.

[0038] The above health functional food composition may include a food-grade acceptable food additive and may include a suitable carrier commonly used in the manufacture of health functional foods.

[0039] In this specification, the term "prevention" may mean partially or completely delaying or preventing the onset or recurrence of a disease, disorder, or its associated symptoms, preventing the acquisition or reacquisition of a disease or disorder, or reducing the risk of acquiring a disease or disorder. Such prevention may refer to any act of suppressing or delaying the occurrence of diabetes or kidney disease, or related disorders or symptoms, through the administration of a composition according to the present invention.

[0040] In this specification, the term "improvement" may mean any action that at least reduces the degree of a parameter, for example, a condition in which diabetes or kidney disease, or related disorders or symptoms, are treated.

[0041] The above-mentioned health functional food may have one or more formulations selected from the group consisting of tablets, granules, pills, capsules, liquids, jellies, and gums, and may be for oral consumption. More specifically, the above-mentioned health functional food may be in the form of a tablet.

[0043] Another aspect provides a health functional food composition for the prevention or improvement of diabetes or kidney disease comprising chitosan, silkworm powder, calcium carbonate, ginkgo leaf extract, and magnesium oxide, wherein the composition further comprises vitamin B12, magnesium stearate, crystalline cellulose, vitamin D3, zinc oxide, a mixture of lactose, pectin, and flavoring, and glucosamine hydrochloride, for lowering blood sugar or inhibiting advanced glycation end products. The same as described above applies equally to the health functional food composition. Effects of the invention

[0045] The above health functional food composition optimized the individual content of various active ingredients, such as chitosan, silkworm powder, calcium carbonate, ginkgo leaf extract, and magnesium oxide, as well as the extraction conditions of the complex extract; and confirmed significant effects in the prevention or improvement of diabetes or kidney disease depending on the combination of chitosan, silkworm powder, and ginkgo leaf extract. Specific details for implementing the invention

[0047] The following examples will be explained in more detail. However, these examples are for illustrative purposes only and the scope of the present invention is not limited to these examples.

[0049] Experimental Example 1. Preparation of a composition comprising chitosan, silkworm powder, ginkgo leaf extract, and calcium carbonate, etc.

[0051] 1.1 Preparation of a complex extract powder containing chitosan, silkworm powder, and ginkgo leaf extract

[0052] Domestic chitosan (average molecular weight approximately 100 kDa, degree of deacetylation 85% or higher, Sigma-Aldrich), silkworm powder (dried silkworm powder, Baekgangjam), and ginkgo leaf extract were prepared.

[0053] For the ginkgo leaf extract, 100 g of domestically produced dried ginkgo leaves (moisture content 10% or less) were weighed and placed into an extraction vessel, and 1,000 mL of purified water was added to set the solvent ratio to approximately 10 times the solid content. After adding the solvent, stirring extraction was performed for 2 hours in a 60°C water bath (at 500 rpm). Subsequently, the extract was filtered once using a 100 mesh stainless steel filter, and the filtrate was concentrated using a vacuum concentrator (Rotary evaporator, 50°C, 200 mbar) to remove the solvent. The concentration was set to end when the solid content of the extract reached approximately 15% (w / w), and a homogeneous ginkgo leaf extract was obtained by checking the viscosity and color (brown viscous liquid) after the concentration was finished.

[0054] Subsequently, 17.0 g of silkworm powder and an amount corresponding to 9.0 g of the solid content of the prepared Ginkgo leaf extract were weighed and added to 100 mL of purified water. The mixture was then stirred and extracted in a 60°C water bath for 2 hours. After extraction, the mixture was filtered through a 100-mesh filter to remove suspended solids. Next, 44.0 g of chitosan was slowly added to a 1% aqueous acetic acid solution (total volume 300 mL) while stirring at 500 rpm for at least 3 hours to completely dissolve it. Subsequently, the silkworm / Ginkgo leaf extract filtrate prepared above was added and mixed homogeneously. This mixture was concentrated to approximately one-third of its original volume using a vacuum concentrator (at 50°C under reduced pressure). The concentrated complex extract was powdered using a spray dryer (dual-fluid nozzle type, inlet temperature 160°C, outlet temperature 80°C) to obtain the complex extract powder. The final manufactured powder consists of fine particles ranging from white to pale yellow, with a moisture content controlled to be 5% or less.

[0056] 1.2 Preparation of an example composition containing chitosan, silkworm powder, ginkgo leaf extract, and calcium carbonate, etc.

[0057] Based on the above-described complex extract powder (44 parts by weight of chitosan, 17 parts by weight of silkworm powder, and 9 parts by weight of ginkgo leaf extract, respectively), 15.0 parts by weight of calcium carbonate, 5.6 parts by weight of magnesium oxide, 2.0 parts by weight of vitamin B12, 2.0 parts by weight of magnesium stearate, 2.0 parts by weight of crystalline cellulose, 1.0 parts by weight of vitamin D3, 1.0 parts by weight of zinc oxide, 1.0 parts by weight of a lactose-pectin-strawberry flavor mixture, and 0.4 parts by weight of glucosamine hydrochloride were added sequentially.

[0058] Specifically, considering particle size and dispersibility, crystalline cellulose and a mixture of lactose, pectin, and strawberry flavor were first added, and then stirred for 10 minutes in a premixer (V-type mixer) together with the complex extract powder. Subsequently, calcium carbonate and magnesium oxide were added, and dry mixing was performed again for 15 minutes at 40 rpm. Next, vitamin D3 and vitamin B12 dissolved in a small amount of ethanol (for food additives, 95%) were sprayed into the mixture in mist form, and low-speed mixing was performed for an additional 10 minutes at a stirring speed of 60 rpm. Then, zinc oxide and glucosamine hydrochloride were added and uniformly mixed in a high-speed blender for 5 minutes, and finally, magnesium stearate was added and low-speed mixing was performed for 5 minutes to prevent granulation. The final prepared composition was controlled to have a moisture content of 5% or less and a particle size (D50) in the range of approximately 100 to 300 μm.

[0060] Experimental Example 2. Preparation of compositions for Examples and Comparative Examples according to differences in extraction conditions and content, etc.

[0061] The compositions of Examples 2 and 3 were prepared using the same method and content as in Experimental Example 1, except that the extraction solvent, extraction conditions, and pulverization conditions of the complex extract were different (Table 1).

[0062] In addition, compositions of Comparative Examples 1 to 6 were prepared in the same manner as in Experimental Example 1, except that the content of the complex extract powder, calcium carbonate, and other active ingredients (vitamin B12, vitamin D3, and zinc oxide) was different (Table 2).

[0063] [Table 1]

[0064]

[0065] [Table 2]

[0066]

[0068] Experimental Example 3. Evaluation of α-glucosidase inhibitory activity

[0069] To confirm the carbohydrate digestion enzyme inhibitory effect of the composition of the present invention, an α-glucosidase inhibitory activity evaluation was performed.

[0070] Specifically, the substrate used in the test is p-Nitrophenyl-α-D-glucopyranoside (PNPG, Sigma-Aldrich), and the enzyme is Saccharomyces cerevisiae α-glucosidase derived from Sigma-Aldrich was used. Using 0.1 M phosphate buffer (pH 6.8) as the reaction buffer, the compositions of Examples 1 to 3 and Comparative Examples 1 to 6 were each dissolved in distilled water to prepare sample solutions at a concentration of 10 mg / mL. 50 µL of each sample was mixed with α-glucosidase solution (0.5 U / mL, 50 µL) and pretreated at 37°C for 10 minutes. Then, PNPG solution (1 mM, 100 µL) was added and reacted at 37°C for 30 minutes. After the reaction was complete, 1 M Na2CO3 solution (100 µL) was added to stop the reaction, and the absorbance was measured at a wavelength of 405 nm. Acarbose was used as a positive control.

[0071] As a result, in the case of Examples 1 to 3, which varied extraction conditions while maintaining the content ratio of the complex extract powder, calcium carbonate, and other active ingredients, IC 50The values ​​were found to be 231.5 μg / ml, 272.8 μg / ml, and 255.4 μg / ml, respectively, which were levels showing significant inhibitory activity compared to Comparative Examples 1 to 6. In particular, the composition of Example 1, which optimized not only the content ratio of the complex extract powder, calcium carbonate, and other active ingredients but also the extraction conditions, was found to have the best α-glucosidase inhibitory activity compared to Examples 2 and 3 (Table 3).

[0072] From this, it was confirmed that the composition of the present invention is effective in preventing or improving diabetes by suppressing a rapid rise in blood sugar after a meal.

[0073] [Table 3]

[0074]

[0076] Experimental Example 4. Evaluation of Inhibitory Effect on In vitro AGE Formation

[0077] We intended to evaluate whether the composition of the present invention has the effect of reducing kidney tissue damage caused by AGEs-RAGE-mediated inflammatory response and oxidative stress by inhibiting the generation of advanced glycation products (AGEs).

[0078] Specifically, Bovine Serum Albumin (BSA, Sigma-Aldrich) was dissolved in phosphate-buffered saline (PBS, pH 7.4) at a final concentration of 10 mg / mL, and then 0.02% sodium azide (NaN3) was added. Subsequently, D-glucose (Sigma-Aldrich) at a final concentration of 0.5 M was added to prepare an AGEs generation induction reaction solution. For the compositions of the Examples and Comparative Examples 1 to 6, sample solutions were prepared by dissolving them in distilled water and diluting them to a concentration of 200 μg / mL, respectively. An AGEs generation reaction solution containing only BSA-Glucose was used as a control. In addition, aminoguanidine (Sigma-Aldrich), which is widely known for its AGEs inhibitory effect, was used at a concentration of 1 mM as a positive control.

[0079] 200 µL of reaction solution for each sample and control was dispensed into a 96-well plate and reacted for 7 days under dark conditions at 37°C. After 7 days, the amount of generated AGEs was analyzed by fluorescence measurement. Fluorescence characteristics were measured using a Microplate Reader (Molecular Devices) under conditions of an excitation wavelength of 370 nm and an emission wavelength of 440 nm. The inhibition rate of AGEs generation was calculated using the following formula.

[0080]

[0082] As a result, in Examples 1 to 3, which varied extraction conditions while maintaining the content ratio of the complex extract powder, calcium carbonate, and other active ingredients, the inhibition rates of AGEs formation were 66.8%, 51.5%, and 53.2%, respectively, which were levels showing significant inhibitory activity compared to Comparative Examples 1 to 6. In particular, the composition of Example 1, which optimized not only the content ratio of the complex extract powder, calcium carbonate, and other active ingredients but also the extraction conditions, was found to have the best inhibition rate of AGEs formation compared to Examples 2 and 3 (Table 4).

[0083] From this, it was confirmed that the composition of the present invention inhibits the generation of AGEs, thereby being effective in preventing or improving kidney tissue damage caused by AGEs-RAGE-mediated inflammatory responses and oxidative stress.

[0084] [Table 4]

[0085]

[0087] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

Claim 1 43 to 45 parts by weight of chitosan, 16 to 18 parts by weight of silkworm powder, 14 to 16 parts by weight of calcium carbonate, 8 to 10 parts by weight of ginkgo leaf extract, 4.5 to 6.5 parts by weight of magnesium oxide, vitamin B 12 A health functional food composition for preventing or improving diabetes or kidney disease, characterized by comprising 2 parts by weight of magnesium stearate, 1 to 3 parts by weight of crystalline cellulose, 1 to 3 parts by weight of vitamin D3, 1 part by weight of zinc oxide, 0.5 to 1.5 parts by weight of a lactose-pectin-flavoring mixture, and 0.1 to 1.0 parts by weight of glucosamine hydrochloride. Claim 2 delete Claim 3 A health functional food composition for the prevention or improvement of diabetes or kidney disease, wherein, in claim 1, the chitosan:silkworm powder:ginkgo leaf extract is included in the form of a complex extract powder with a weight ratio of 4.8~5.0:1.8~2.0:

1. Claim 4 A health functional food composition for preventing or improving diabetes or kidney disease, wherein, in claim 1, the diabetes is type 1 diabetes, type 2 diabetes, impaired fasting glucose, or impaired glucose tolerance, and the kidney disease is chronic kidney disease, acute kidney injury, glomerulonephritis, kidney inflammation, diabetic nephropathy, or nephrotic syndrome. Claim 5 A health functional food composition for the prevention or improvement of diabetes or kidney disease, wherein, in claim 1, the health functional food is in the form of a tablet.

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