Prebiotics concentrated solution for improving intestinal health as well as preparation method and application of prebiotics concentrated solution

Abstract

The invention relates to the technical field of prebiotics, in particular to a prebiotic concentrated solution for improving intestinal health and a preparation method and application thereof, and the prebiotic concentrated solution comprises the following components in parts by weight: 5-18 parts of fructo-oligosaccharide, 3-10 parts of galactooligosaccharide, 0.8-1.7 parts of isomaltooligosaccharide, 2-5 parts of a synergistic aid and 100-130 parts of water. According to the prebiotic concentrated solution disclosed by the invention, the fructo-oligosaccharide, the galactooligosaccharide, the isomaltooligosaccharide, the synergistic additive and other components are compounded, so that the breeding of pathogenic bacteria of a human body can be effectively inhibited, and meanwhile, the reproduction of beneficial bacteria is not damaged, so that the health of intestinal tracts is favorably maintained, and the synergistic additive can be better adhered to the intestinal wall; catechin is continuously released, so that the effect of improving intestinal health for a long time is realized, and the intestinal health is further promoted.

Description

Technical Field

[0001] This invention relates to the field of prebiotic technology, specifically to a prebiotic concentrate for improving gut health, its preparation method, and its application. Background Technology

[0002] The gut, as the largest digestive organ in the human body, is a vital site for digesting substances, absorbing nutrients, and excreting metabolic waste, playing a crucial role in maintaining normal metabolic function. The human gut is home to over 500 species of bacteria, numbering more than 10^15, forming a vast micro-ecosystem that maintains homeostasis through immune and metabolic pathways. A healthy gut is essential for overall health and daily activities. In recent years, gut microbiota imbalances caused by irregular sleep patterns and poor dietary habits have led to increasingly common symptoms such as bloating, abdominal pain, diarrhea, and various enteritis diseases. Therefore, regulating the gut microbiota to improve gut health and promote overall well-being has become a research hotspot in the life sciences.

[0003] Currently, there are two main methods for adjusting the intestinal microecological environment: one is probiotic supplementation. Normal intestinal flora, especially Bifidobacteria and Lactobacillus, plays a crucial role in maintaining a healthy intestinal flora structure and overall health. However, live bacteria supplementation has several shortcomings in terms of colonization, survival rate, transport, and preservation. The second method is the self-proliferation of beneficial bacteria in the gut, i.e., prebiotic supplementation. The physiological function of prebiotics is mainly achieved by promoting the reproduction of beneficial bacteria in the gut and regulating the balance of the intestinal microecology, manifested in improved intestinal function and enhanced immunity. Prebiotics were proposed based on the concept of probiotics and were initially defined as "an indigestible food component that selectively stimulates one or a limited number of bacteria already present in the colon, altering their growth and activity, thereby beneficially influencing the host." With the innovation and upgrading of microbial research tools (such as high-throughput sequencing), our understanding of the composition of the microbial community has become more comprehensive, and research on prebiotics has become more extensive and in-depth.

[0004] For example, the invention patent with publication number CN108777998A discloses a compound prebiotic for regulating human intestinal function and its application, which includes inulin, galactooligosaccharides, xylitol and yeast β-glucan. The compound prebiotic can regulate the function of human intestinal flora. Several natural prebiotics are selected and combined to work synergistically, and ingredients that can enhance intestinal immunity are added to comprehensively improve intestinal health. However, the adhesion ability of this prebiotic to the large intestine wall is weak, and it cannot stay in the intestine for a long time. It is easily lost, resulting in low utilization rate. Therefore, the effect on intestinal improvement is short-lived, and multiple consumptions are required to achieve good results. Summary of the Invention

[0005] In view of the problems existing in the prior art, the purpose of this invention is to provide a prebiotic concentrate for improving gut health, its preparation method and application.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A prebiotic concentrate for improving gut health, the prebiotic concentrate comprising the following components by weight: 5-18 parts fructooligosaccharide, 3-10 parts galactooligosaccharide, 0.8-1.7 parts isomaltooligosaccharide, 2-5 parts synergist, and 100-130 parts water.

[0008] As a further preferred embodiment of the present invention, the preparation method of the synergistic agent is as follows:

[0009] 1) Add distilled water to rice starch and stir to prepare a suspension with a mass concentration of 40-50%. Then add a compound enzyme at a mass of 3-6% of the suspension. Place the suspension in a water bath shaker and carry out the enzymatic hydrolysis reaction at a speed of 120-150 rpm for 2-3 hours. After the reaction is completed, remove the suspension and add sodium hydroxide solution to terminate the reaction. After centrifugation, discard the supernatant. Then add ultrapure water to disperse the mixture. After centrifugation, discard the supernatant. Repeat the washing process 3-5 times. Freeze-dry the precipitate, grind it, and sieve it to obtain porous rice starch.

[0010] 2) Dissolve chitosan powder in acetic acid solution to obtain chitosan solution, then disperse rice porous starch in chitosan solution, stir and mix thoroughly, freeze dry, grind and place in oven, heat treat at 130-132℃ for 4-6 hours, cool to room temperature and grind to obtain modified porous starch;

[0011] 3) Prepare the catechin solution: Disperse 1-3g of modified porous starch in 10-20mL of catechin solution, add 0.1-0.3g of polylactic acid composite nanofibers, place in a constant temperature water bath at 25-28℃, and shake under ultrasonication for 30-50min. After shaking, add another 10-20mL of catechin solution and 0.1-0.3g of polylactic acid composite nanofibers, and continue to shake under ultrasonication for 30-50min. Repeat the above operation 2-5 times. After the treatment is completed, centrifuge and discard the supernatant. Freeze-dry the precipitate for later use.

[0012] 4) Mix the material obtained by freeze-drying with plant-derived substances and resistant dextrin in a mass ratio of (8-10):(2-4):1 to obtain a synergistic agent.

[0013] As a further preferred embodiment of the present invention, in step 1), the ratio of rice starch, sodium hydroxide solution and ultrapure water is (2-5)g:(1.0-1.5)mL:(40-60)mL;

[0014] The complex enzyme is composed of saccharifying enzyme and α-amylase in a mass ratio of (2-3):1;

[0015] The concentration of the sodium hydroxide solution is 2.0-2.5 mol / mL.

[0016] As a further preferred embodiment of the present invention, in step 2), the ratio of chitosan powder, acetic acid solution and porous rice starch is (1-2)g:(40-60)mL:(3-4)g;

[0017] The concentration of the acetic acid solution is 2-3 wt%.

[0018] As a further preferred embodiment of the present invention, in step 3), the concentration of the catechin solution is 2-3 g / L; the power of the ultrasonic treatment is 200-300 W; and the rotation speed of the oscillation is 120-180 rpm.

[0019] In step 4), the plant-derived substance is composed of okra pectin, cranberry powder, inulin, and tea polyphenols in a mass ratio of 1:(1.0-1.6):(1.2-2.0):(0.3-0.7).

[0020] As a further preferred embodiment of the present invention, the method for preparing the polylactic acid composite nanofibers is as follows:

[0021] 1) After crushing fig, Atractylodes macrocephala and Rehmannia glutinosa into plant powder, add them to distilled water at 23-28℃ and soak for 1-2 hours. Then add citric acid and extract with water at 82-86℃. After water extraction, filter to obtain filtrate. Then add lactoferrin to the filtrate, stir evenly, and treat with ultrasound for 20-30 minutes. Then irradiate with γ-rays at a dose of 5-10 kGy. After irradiation, concentrate under reduced pressure and dry to obtain plant polysaccharide extract.

[0022] 2) Add the plant polysaccharide extract to the polylactic acid solution and stir thoroughly to obtain a mixture. Then, use the mixture as the spinning solution. Draw the spinning solution into a syringe, equip it with a No. 21 metal electrospinning needle, place it horizontally on the syringe pump, and perform electrospinning under the conditions of a push speed of 1.0-1.3 mL / h, a positive electrode voltage of 20-23 kV, a negative electrode voltage of 2-3 kV, and a distance of 12-15 cm between the needle and the collecting plate to obtain polylactic acid composite nanofibers.

[0023] As a further preferred embodiment of the present invention, in step 1), the ratio of fig, Atractylodes macrocephala, Rehmannia glutinosa, distilled water and citric acid is (30-50)g:(20-28)g:(13-16)g:(1200-1800)mL:(0.3-0.6)g;

[0024] The ratio of the filtrate to lactoferrin is (100-130) mL: (3-5) g;

[0025] The power of the ultrasonic treatment is 300-500W.

[0026] As a further preferred embodiment of the present invention, in step 2), the concentration of the polylactic acid solution is 10-13 wt%.

[0027] The content of plant polysaccharide extract in the mixture is 0.5-1.0 wt%.

[0028] A method for preparing a prebiotic concentrate for improving gut health, specifically including the following steps:

[0029] Weigh out water, fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharides, and synergistic agents according to the formula, mix them thoroughly, concentrate under reduced pressure to 30-50% of the original volume, and then fill and sterilize to obtain the final product.

[0030] Application of a prebiotic concentrate for improving gut health in baked goods, beverages, preserved fruits, oatmeal, milk, braised food, mooncakes, as well as general foods and various functional products.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] In this invention, fig, Atractylodes macrocephala, and Rehmannia glutinosa are used as raw materials. A plant polysaccharide extract is obtained through water extraction, which has excellent antioxidant and antibacterial effects. After thoroughly mixing the plant polysaccharide extract with a polylactic acid solution, electrospinning is performed to obtain polylactic acid composite nanofibers. By incorporating functional plant polysaccharide extracts into polylactic acid, the polylactic acid fibers are endowed with excellent antioxidant and antibacterial effects, thereby preventing the prebiotic concentrate from oxidizing and deteriorating, as well as the growth of microorganisms, thus helping to extend the shelf life of the prebiotic concentrate. Simultaneously, using rice starch as raw material, porous rice starch was prepared via enzymatic method, and then modified with chitosan to obtain modified porous starch. Since chitosan carries a positive charge, the structure of the porous rice starch remained intact after modification and retained its positive charge, thus facilitating the subsequent adsorption of catechins. Utilizing the porous structure of the modified porous starch, under capillary action and supplemented by ultrasonic action, catechins and polylactic acid composite nanofibers could better penetrate into the pores of the modified porous starch, forming a loading layer. Polylactic acid (PLA) composite nanofibers, through intertwining to form a network structure, can act as a confinement agent, inhibiting the flow of catechins. Furthermore, in this invention, by infiltrating catechins and PLA composite nanofibers into modified porous starch in batches, catechin stratification is formed within the pores of the modified porous starch, allowing for the phased release of catechins and significantly improving their utilization rate. Simultaneously, the stratification also helps improve the stability of catechins within the pores, preventing loss. The infiltrated catechins can inhibit the growth of pathogenic bacteria (such as Clostridium botulinum) without harming the proliferation of beneficial bacteria (such as lactic acid bacteria), thus contributing to maintaining intestinal health. Additionally, some PLA composite nanofibers infiltrating the modified porous starch are exposed, increasing their specific surface area and surface roughness, thereby increasing their contact area with the intestinal wall and strengthening the bond between them. This allows for better adhesion to the intestinal wall, continuously releasing catechins and achieving long-term improvement in intestinal health.

[0033] The prebiotic concentrate in this invention, through the compounding of components such as fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharides, and synergistic agents, can effectively inhibit the growth of pathogenic bacteria in the human body without harming the reproduction of beneficial bacteria, thereby helping to maintain intestinal health. Furthermore, the synergistic agents can better adhere to the intestinal wall and continuously release catechins, thereby achieving a long-term effect of improving intestinal health and promoting intestinal health. Detailed Implementation

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Example 1

[0036] A prebiotic concentrate for improving gut health, comprising the following components by weight: 5 parts fructooligosaccharide, 3 parts galactooligosaccharide, 0.8 parts isomaltooligosaccharide, 2 parts synergist, and 100 parts water.

[0037] The preparation method of this prebiotic concentrate includes the following steps:

[0038] Weigh out water, fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharides, and synergistic agents according to the formula, mix them thoroughly, concentrate under reduced pressure to 30% of the original volume, and then fill and sterilize to obtain the final product.

[0039] The preparation method of the synergistic agent is as follows:

[0040] 1) Crush 30g of fig, 20g of Atractylodes macrocephala, and 13g of Rehmannia glutinosa to obtain plant powder, add them to 1200mL of distilled water at 23℃, soak for 1h, then add 0.3g of citric acid, and extract with water at 82℃. After water extraction, filter to obtain filtrate, then add 3g of lactoferrin to 100mL of filtrate, stir evenly, treat with 300W ultrasound for 20min, and then irradiate with γ-rays at a dose of 5kGy. After irradiation, concentrate under reduced pressure and dry to obtain plant polysaccharide extract.

[0041] 2) Plant polysaccharide extract was added to a 10wt% polylactic acid solution and stirred thoroughly to obtain a mixture with a plant polysaccharide extract content of 0.5wt%. The mixture was then used as the spinning solution. The spinning solution was drawn into a syringe and equipped with a No. 21 metal electrospinning needle, which was placed horizontally on the syringe pump. Electrospinning was carried out under the conditions of a push speed of 1.0mL / h, a positive electrode voltage of 20kV, a negative electrode voltage of 2kV, and a distance of 12cm between the needle and the collecting plate to obtain polylactic acid composite nanofibers.

[0042] 3) Add distilled water to 2g of rice starch and stir to make a suspension with a mass concentration of 40-50%. Then add a complex enzyme composed of saccharifying enzyme and α-amylase in a mass ratio of 2:1. The amount of complex enzyme added is 3% of the mass of the suspension. Place it in a water bath shaker and carry out the enzymatic hydrolysis reaction at 120rpm for 2h. After the reaction is completed, remove it and add 1.0mL of 2.0mol / mL sodium hydroxide solution to terminate the reaction. After centrifugation, discard the supernatant. Then add 40mL of ultrapure water for dispersion. After centrifugation, discard the supernatant. Repeat the washing process 3 times. After that, freeze-dry the precipitate, grind it and sieve it to obtain porous rice starch.

[0043] 4) Dissolve 1g of chitosan powder in 40mL of 2wt% acetic acid solution to obtain chitosan solution. Then disperse 3g of rice porous starch in chitosan solution, stir and mix thoroughly, freeze dry, grind and place in an oven, heat treat at 130℃ for 4h, cool to room temperature and grind to obtain modified porous starch.

[0044] 5) Prepare a catechin solution with a concentration of 2 g / L. Disperse 1 g of modified porous starch in 10 mL of catechin solution and add 0.1 g of polylactic acid composite nanofibers. Place the solution in a 25°C constant temperature water bath and shake at 120 rpm for 30 min under 200 W ultrasonic treatment. After shaking, add another 10 mL of catechin solution and 0.1 g of polylactic acid composite nanofibers. Continue to shake at 120 rpm for 30 min under 200 W ultrasonic treatment. Repeat the above operation twice. After the treatment is completed, centrifuge and discard the supernatant. Freeze-dry the precipitate for later use.

[0045] 6) Mix the material obtained by freeze-drying with plant-derived substances and resistant dextrin at a mass ratio of 8:2:1 to obtain the synergistic agent.

[0046] The plant-derived substances consist of okra pectin, cranberry powder, inulin, and tea polyphenols in a mass ratio of 1:1:1.2:0.3.

[0047] Example 2

[0048] A prebiotic concentrate for improving gut health, comprising the following components by weight: 13 parts fructooligosaccharide, 7 parts galactooligosaccharide, 1.3 parts isomaltooligosaccharide, 3 parts synergist, and 120 parts water.

[0049] The preparation method of this prebiotic concentrate includes the following steps:

[0050] Weigh out water, fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharides, and synergistic agents according to the formula, mix them thoroughly, concentrate under reduced pressure to 40% of the original volume, and then fill and sterilize to obtain the final product.

[0051] The preparation method of the synergistic agent is as follows:

[0052] 1) Crush 40g of fig, 25g of Atractylodes macrocephala, and 15g of Rehmannia glutinosa to obtain plant powder, add them to 1500mL of distilled water at 25℃, soak for 1.5h, then add 0.5g of citric acid, and extract with water at 84℃. After water extraction, filter to obtain filtrate, then add 4g of lactoferrin to 120mL of filtrate, stir evenly, treat with ultrasound at 400W for 25min, and then irradiate with γ-rays at a dose of 8kGy. After irradiation, concentrate under reduced pressure and dry to obtain plant polysaccharide extract.

[0053] 2) Plant polysaccharide extract was added to a 12wt% polylactic acid solution and stirred thoroughly to obtain a mixture with a plant polysaccharide extract content of 0.8wt%. The mixture was then used as the spinning solution. The spinning solution was drawn up with a syringe, equipped with a No. 21 metal electrospinning needle, and placed horizontally on the syringe pump. Electrospinning was carried out under the conditions of a push speed of 1.2mL / h, a positive electrode voltage of 21kV, a negative electrode voltage of 2kV, and a distance of 13cm between the needle and the collecting plate to obtain polylactic acid composite nanofibers.

[0054] 3) Add distilled water to 3g of rice starch and stir to prepare a suspension with a mass concentration of 40-50%. Then add a complex enzyme composed of saccharifying enzyme and α-amylase in a mass ratio of 2.5:1. The amount of complex enzyme added is 5% of the mass of the suspension. Place it in a water bath shaker and carry out the enzymatic hydrolysis reaction at 130rpm for 2.5h. After the reaction is completed, remove it and add 1.3mL of 2.2mol / mL sodium hydroxide solution to terminate the reaction. After centrifugation, discard the supernatant. Then add 50mL of ultrapure water for dispersion. After centrifugation, discard the supernatant. Repeat the washing process 4 times. After that, freeze-dry the precipitate, grind it, and sieve it to obtain porous rice starch.

[0055] 4) Dissolve 1.5g of chitosan powder in 50mL of 2.5wt% acetic acid solution to obtain chitosan solution. Then disperse 3.5g of rice porous starch in chitosan solution, stir and mix thoroughly, freeze dry, grind and place in an oven, heat treat at 131℃ for 5h, cool to room temperature and grind to obtain modified porous starch.

[0056] 5) Prepare a catechin solution with a concentration of 2.5 g / L. Disperse 2 g of modified porous starch in 15 mL of catechin solution and add 0.2 g of polylactic acid composite nanofibers. Place the solution in a 26°C constant temperature water bath and sonicate at 150 rpm for 40 min under 260 W ultrasound. After sonication, add another 15 mL of catechin solution and 0.2 g of polylactic acid composite nanofibers. Continue to sonicate at 150 rpm for 40 min under 260 W ultrasound. Repeat the above operation 3 times. After the treatment is completed, centrifuge and discard the supernatant. Freeze-dry the precipitate for later use.

[0057] 6) Mix the material obtained by freeze-drying with plant-derived substances and resistant dextrin at a mass ratio of 9:3:1 to obtain the synergistic agent.

[0058] The plant-derived substances consist of okra pectin, cranberry powder, inulin, and tea polyphenols in a mass ratio of 1:1.4:1.7:0.5.

[0059] Example 3

[0060] A prebiotic concentrate for improving gut health, comprising the following components by weight: 18 parts fructooligosaccharides, 10 parts galactooligosaccharides, 1.7 parts isomaltooligosaccharides, 5 parts synergist, and 130 parts water.

[0061] The preparation method of this prebiotic concentrate includes the following steps:

[0062] Weigh out water, fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharides, and synergistic agents according to the formula, mix them thoroughly, concentrate under reduced pressure to 50% of the original volume, and then fill and sterilize to obtain the final product.

[0063] The preparation method of the synergistic agent is as follows:

[0064] 1) Crush 50g of fig, 28g of Atractylodes macrocephala, and 16g of Rehmannia glutinosa to obtain plant powder, add them to 1800mL of distilled water at 28℃, soak for 2h, then add 0.6g of citric acid, and extract with water at 86℃. After water extraction, filter to obtain filtrate, then add 5g of lactoferrin to 130mL of filtrate, stir evenly, treat with 500W sonication for 30min, and then irradiate with γ-rays at a dose of 10kGy. After irradiation, concentrate under reduced pressure and dry to obtain plant polysaccharide extract.

[0065] 2) Plant polysaccharide extract was added to a polylactic acid solution with a concentration of 13wt%. After thorough stirring, a mixture with a plant polysaccharide extract content of 1.0wt% was obtained. The mixture was then used as the spinning solution. The spinning solution was drawn up with a syringe, equipped with a No. 21 metal electrospinning needle, which was placed horizontally on the syringe pump. Electrospinning was carried out under the conditions of a push speed of 1.3mL / h, a positive electrode voltage of 23kV, a negative electrode voltage of 3kV, and a distance of 15cm between the needle and the collecting plate to obtain polylactic acid composite nanofibers.

[0066] 3) Add distilled water to 5g of rice starch and stir to make a suspension with a mass concentration of 40-50%. Then add a complex enzyme composed of saccharifying enzyme and α-amylase in a mass ratio of 3:1. The amount of complex enzyme added is 6% of the mass of the suspension. Place it in a water bath shaker and carry out the enzymatic hydrolysis reaction at 150rpm for 3h. After the reaction is completed, remove it and add 1.5mL of 2.5mol / mL sodium hydroxide solution to terminate the reaction. After centrifugation, discard the supernatant. Then add 60mL of ultrapure water for dispersion. After centrifugation, discard the supernatant. Repeat the washing process 5 times. After that, freeze-dry the precipitate, grind it and sieve it to obtain porous rice starch.

[0067] 4) Dissolve 2g of chitosan powder in 60mL of 3wt% acetic acid solution to obtain chitosan solution. Then disperse 4g of rice porous starch in chitosan solution, stir and mix thoroughly, freeze dry, grind and place in an oven, heat treat at 132℃ for 6h, cool to room temperature and grind to obtain modified porous starch.

[0068] 5) Prepare a catechin solution with a concentration of 3 g / L. Disperse 3 g of modified porous starch in 20 mL of catechin solution and add 0.3 g of polylactic acid composite nanofibers. Place the solution in a 28°C constant temperature water bath and shake at 180 rpm for 50 min under 300 W ultrasonic treatment. After shaking, add another 20 mL of catechin solution and 0.3 g of polylactic acid composite nanofibers. Continue to shake at 180 rpm for 50 min under 300 W ultrasonic treatment. Repeat the above operation 5 times. After the treatment is completed, centrifuge and discard the supernatant. Freeze-dry the precipitate for later use.

[0069] 6) Mix the material obtained by freeze-drying with plant-derived substances and resistant dextrin at a mass ratio of 10:4:1 to obtain a synergistic agent.

[0070] The plant-derived substances consist of okra pectin, cranberry powder, inulin, and tea polyphenols in a mass ratio of 1:1.6:2:0.7.

[0071] Comparative Example 1: This comparative example is basically the same as Example 1, except that it does not contain a synergist.

[0072] Comparative Example 2: This comparative example is basically the same as Example 1, except that step 1 is omitted in the preparation process of the synergist.

[0073] Comparative Example 3: This comparative example is basically the same as Example 1, except that steps 1)-2) are omitted in the preparation process of the synergist.

[0074] Comparative Example 4: This comparative example is basically the same as Example 1, except that step 4 is omitted in the preparation process of the synergist.

[0075] Comparative Example 5: This comparative example is basically the same as Example 1, except that the repeated operation process in step 5) is omitted in the preparation of the synergist, and the treatment of catechin and polylactic acid composite nanofibers is only performed once.

[0076] Test experiment:

[0077] Two hundred Kunming mice, half male and half female, were randomly divided into 10 groups of 20 mice each: blank group, model control group, Example 1 group, Example 2 group, Example 3 group, Comparative Example 1 group, Comparative Example 2 group, Comparative Example 3 group, Comparative Example 4 group, and Comparative Example 5 group. Except for the blank group, all groups were administered loperamide hydrochloride at a dose of 10 mg / kg bw once daily by gavage for 7 consecutive days. All mice had free access to food and water to establish a constipation model. The mice were then administered the prepared intestinal health-promoting fruit juice drink by gavage, while the blank group and model control group were administered an equal volume of physiological saline by gavage at a dose of 0.2 mL daily for 10 consecutive days. All mice had free access to food and water. After 10 days, all groups were fasted but allowed free access to water for 12 hours. Then, each group underwent a final gavage. One hour after administration, activated charcoal was given. Fifteen minutes later, the mice were euthanized by dislocation, the mesentery was separated from the abdominal cavity, the small intestine was excised, the distance the charcoal was propelled was measured, and the small intestinal propulsion rate (%) was calculated.

[0078] Propulsion rate (%) = Activated carbon propulsion length (cm) / Total small intestine length (cm) × 100%

[0079] Table 1 Results of the small intestine propulsion experiment

[0080] Mouse number Small intestine propulsion rate % Blank group 20 80.32 Model control group 20 48.96 Example 1 Group 20 90.13 Example 2 group 20 91.07 Example 3 Group 20 90.76 Comparative Example 1 20 51.27 Comparative Example 2 20 68.94 Comparative Example 3 Groups 20 62.81 Comparative Example 4 Groups 20 76.92 Comparative Example 5 Groups 20 83.45

[0081] As shown in Table 1 above, the small intestinal propulsion rate of the model control group was significantly lower than that of the blank group, indicating that the constipation model was successful. At the same time, the prebiotic concentrate prepared in this invention (Examples 1-3) had a significantly higher small intestinal propulsion rate than Comparative Example 1, Comparative Example 2, Comparative Example 3, Comparative Example 4, Comparative Example 5 and the model control group, indicating that it can effectively promote gastrointestinal motility, accelerate fecal excretion, and has a significant effect on improving intestinal health. Moreover, based on the dosage and duration of continuous use, it can be seen that the prebiotic concentrate in this invention has a high utilization rate, requires a small dosage, and has a short treatment period to achieve a good effect on improving intestinal health.

[0082] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A prebiotic concentrate for improving gut health, characterized in that, The prebiotic concentrate comprises the following components by weight: 5-18 parts fructooligosaccharide, 3-10 parts galactooligosaccharide, 0.8-1.7 parts isomaltooligosaccharide, 2-5 parts synergist, and 100-130 parts water.

2. The prebiotic concentrate for improving gut health according to claim 1, characterized in that, The preparation method of the synergistic agent is as follows: 1) Add distilled water to rice starch and stir to prepare a suspension with a mass concentration of 40-50%. Then add a compound enzyme at a mass of 3-6% of the suspension. Place the suspension in a water bath shaker and carry out the enzymatic hydrolysis reaction at a speed of 120-150 rpm for 2-3 hours. After the reaction is completed, remove the suspension and add sodium hydroxide solution to terminate the reaction. After centrifugation, discard the supernatant. Then add ultrapure water to disperse the mixture. After centrifugation, discard the supernatant. Repeat the washing process 3-5 times. Freeze-dry the precipitate, grind it, and sieve it to obtain porous rice starch. 2) Dissolve chitosan powder in acetic acid solution to obtain chitosan solution, then disperse rice porous starch in chitosan solution, stir and mix thoroughly, freeze dry, grind and place in oven, heat treat at 130-132℃ for 4-6 hours, cool to room temperature and grind to obtain modified porous starch; 3) Prepare the catechin solution: Disperse 1-3g of modified porous starch in 10-20mL of catechin solution, add 0.1-0.3g of polylactic acid composite nanofibers, place in a constant temperature water bath at 25-28℃, and shake under ultrasonication for 30-50min. After shaking, add another 10-20mL of catechin solution and 0.1-0.3g of polylactic acid composite nanofibers, and continue to shake under ultrasonication for 30-50min. Repeat the above operation 2-5 times. After the treatment is completed, centrifuge and discard the supernatant. Freeze-dry the precipitate for later use. 4) Mix the material obtained by freeze-drying with plant-derived substances and resistant dextrin in a mass ratio of (8-10):(2-4):1 to obtain a synergistic agent.

3. The prebiotic concentrate for improving gut health according to claim 2, characterized in that, In step 1), the ratio of rice starch, sodium hydroxide solution, and ultrapure water is (2-5)g:(1.0-1.5)mL:(40-60)mL; The complex enzyme is composed of saccharifying enzyme and α-amylase in a mass ratio of (2-3):1; The concentration of the sodium hydroxide solution is 2.0-2.5 mol / mL.

4. The prebiotic concentrate for improving gut health according to claim 2, characterized in that, In step 2), the ratio of chitosan powder, acetic acid solution, and porous rice starch is (1-2)g:(40-60)mL:(3-4)g; The concentration of the acetic acid solution is 2-3 wt%.

5. A prebiotic concentrate for improving gut health according to claim 2, characterized in that, In step 3), the concentration of the catechin solution is 2-3 g / L; the power of the ultrasonic treatment is 200-300 W; and the rotation speed of the oscillation is 120-180 rpm. In step 4), the plant-derived substance is composed of okra pectin, cranberry powder, inulin, and tea polyphenols in a mass ratio of 1:(1.0-1.6):(1.2-2.0):(0.3-0.7).

6. The prebiotic concentrate for improving gut health according to claim 2, characterized in that, The preparation method of the polylactic acid composite nanofibers is as follows: 1) After crushing fig, Atractylodes macrocephala and Rehmannia glutinosa into plant powder, add them to distilled water at 23-28℃ and soak for 1-2 hours. Then add citric acid and extract with water at 82-86℃. After water extraction, filter to obtain filtrate. Then add lactoferrin to the filtrate, stir evenly, and treat with ultrasound for 20-30 minutes. Then irradiate with γ-rays at a dose of 5-10 kGy. After irradiation, concentrate under reduced pressure and dry to obtain plant polysaccharide extract. 2) Add the plant polysaccharide extract to the polylactic acid solution and stir thoroughly to obtain a mixture. Then, use the mixture as the spinning solution. Draw the spinning solution into a syringe, equip it with a No. 21 metal electrospinning needle, place it horizontally on the syringe pump, and perform electrospinning under the conditions of a push speed of 1.0-1.3 mL / h, a positive electrode voltage of 20-23 kV, a negative electrode voltage of 2-3 kV, and a distance of 12-15 cm between the needle and the collecting plate to obtain polylactic acid composite nanofibers.

7. A prebiotic concentrate for improving gut health according to claim 6, characterized in that, In step 1), the ratio of fig, Atractylodes macrocephala, Rehmannia glutinosa, distilled water, and citric acid is (30-50)g:(20-28)g:(13-16)g:(1200-1800)mL:(0.3-0.6)g; The ratio of the filtrate to lactoferrin is (100-130) mL: (3-5) g; The power of the ultrasonic treatment is 300-500W.

8. A prebiotic concentrate for improving gut health according to claim 6, characterized in that, In step 2), the concentration of the polylactic acid solution is 10-13 wt%. The content of plant polysaccharide extract in the mixture is 0.5-1.0 wt%.

9. The method for preparing a prebiotic concentrate for improving gut health according to claim 1, characterized in that, Specifically, the steps include the following: Weigh out water, fructooligosaccharides, galactooligosaccharides, isomaltooligosaccharides, and synergistic agents according to the formula, mix them thoroughly, concentrate under reduced pressure to 30-50% of the original volume, and then fill and sterilize to obtain the final product.

10. The application of a prebiotic concentrate for improving gut health as described in any one of claims 1-9 in baked goods, beverages, preserved fruits, oatmeal, milk, braised food, mooncakes, as well as general foods and various functional products.