Fructooligosaccharides for improving gut health and methods of making and using the same
The production of oligofructose by fermenting Aspergillus niger and Aspergillus oryzae with mixed fructosyltransferases solves the problem of poor intestinal health improvement in existing technologies, and achieves significant effects in promoting intestinal peristalsis, increasing the number of probiotics and mineral absorption, which can be applied to food.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- KING POLO(YUNFU) TRADING CORP
- Filing Date
- 2024-11-25
- Publication Date
- 2026-05-29
AI Technical Summary
In existing technologies, fructooligosaccharides prepared from sucrose have a poor effect on improving gut health.
Mixed fructosyltransferases were prepared by fermentation of Aspergillus niger and Aspergillus oryzae. Fructooligosaccharides were produced by fermenting sucrose. The fructooligosaccharides were then purified and dried by ammonium sulfate precipitation, ion exchange chromatography and spray drying to obtain fructooligosaccharides that improve gut health.
It significantly promotes intestinal peristalsis, increases the number of bifidobacteria and lactic acid bacteria in the intestine, and improves the absorption of minerals. When applied to foods such as baked goods, candies, and beverages, it enhances immunity, regulates intestinal flora, and promotes digestion and bowel movements.
Smart Images
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Figure BDA0005150481550000091
Abstract
Description
Technical Field
[0001] This invention relates to the field of food processing technology, and in particular to an oligofructose for improving gut health, its preparation method, and its application. Background Technology
[0002] Fructose oligosaccharides, also known as oligofructose, sucrose oligofructose, or fructooligosaccharides, are natural active ingredients found in fruits, vegetables, grains, and other substances. Due to their pleasant taste and food stability, frucose oligosaccharides are often used as sweeteners to improve the texture and flavor of food. In the human body, frucose oligosaccharides also possess various physiological and pharmacological activities. For example, they can increase the number of beneficial bacteria in the gut, promote intestinal peristalsis, and improve the intestinal environment; dissolve minerals such as calcium, magnesium, and iron, promoting the body's absorption of these minerals; and enhance immunity, preventing disease. Therefore, frucose oligosaccharides offer numerous health benefits and are increasingly becoming a research hotspot in this field.
[0003] However, the content of fructooligosaccharides (FOS) in natural foods is generally low. Therefore, FOS are usually produced industrially using sucrose. However, most FOS products prepared from sucrose using existing technologies have poor effects on improving gut health. Therefore, it is necessary to provide a method for preparing FOS that can significantly improve gut health. Summary of the Invention
[0004] The purpose of this invention is to provide an oligofructose that improves gut health, its preparation method, and its application, thereby solving the problem that oligofructose extracted by existing production methods has poor gut health improvement effects.
[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:
[0006] A method for preparing fructooligosaccharides that improve gut health includes the following steps:
[0007] (1) Aspergillus niger was inoculated into a culture medium and cultured to obtain Aspergillus niger fermentation broth. The liquid part of the Aspergillus niger fermentation broth was extracted and collected. After separation and purification, fructosyltransferase from Aspergillus niger was obtained.
[0008] (2) Aspergillus oryzae was inoculated into a culture medium and cultured to obtain Aspergillus oryzae fermentation broth. The liquid part of the Aspergillus oryzae fermentation broth was extracted and collected. After separation and purification, the fructosyltransferase from Aspergillus oryzae was obtained.
[0009] (3) Mix the fructosyltransferase from Aspergillus niger obtained in step (1) with the fructosyltransferase from Aspergillus oryzae obtained in step (2) to obtain a mixed fructosyltransferase.
[0010] (4) After mixing sucrose with water, inoculate the mixed fructosyltransferase obtained in step (3) and ferment under anaerobic conditions to obtain a solution containing oligofructose.
[0011] (5) After separating, purifying and drying the solution containing oligofructose obtained in step (4), oligofructose is obtained.
[0012] Preferably, the culture medium in step (1) is PDA culture medium, which also contains CaCl2 at a concentration of 0.15 to 0.25 g / L; the culture temperature is 20 to 30°C, the rate is 150 to 200 rpm, and the time is 40 to 56 h.
[0013] Preferably, the culture medium in step (2) is PDA culture medium; the culture temperature is 20-30℃, the rate is 150-200rpm, and the time is 40-56h.
[0014] Preferably, the separation and purification methods described in steps (1) and (2) are ammonium sulfate precipitation and ion exchange chromatography.
[0015] Preferably, the mass ratio of the fructosyltransferase from Aspergillus niger and the fructosyltransferase from Aspergillus oryzae in step (3) is 1.5-2.5:0.8-1.2.
[0016] Preferably, in step (4), the concentration of sucrose after mixing with water is 20-30%; the concentration of the mixed fructosyltransferase is 400-600 U / mL; and the fermentation temperature is 40-60℃ and the time is 20-30h.
[0017] Preferably, the separation and purification method in step (5) is cation exchange resin method and ultrafiltration method; the drying is spray drying, and the spray drying temperature is 160-170℃.
[0018] This invention provides an oligofructose prepared according to the method described above.
[0019] The present invention also provides an application of the aforementioned fructooligosaccharide in food preparation, the food including baked goods, confectionery and beverages.
[0020] Preferably, the food is a general food, functional food, health food, or infant formula that has the functions of enhancing immunity, regulating intestinal flora, promoting digestion and relieving constipation.
[0021] This invention involves inoculating *Aspergillus niger* into a culture medium containing CaCl2 and culturing it, then isolating and purifying *Aspergillus niger*-derived fructosyltransferase from the fermentation broth. Furthermore, this invention uses a mixture of *Aspergillus niger*-derived fructosyltransferase and *Aspergillus oryzae*-derived fructosyltransferase for the production of fructooligosaccharides. The fructooligosaccharides produced by this invention significantly promote intestinal peristalsis, improve intestinal flora, and enhance the body's ability to absorb minerals. They can be applied to the preparation of foods that enhance immunity, regulate intestinal flora, promote digestion, and relieve constipation, playing a positive role in the development of foods that maintain human intestinal health. Detailed Implementation
[0022] A method for preparing fructooligosaccharides that improve gut health includes the following steps:
[0023] (1) Aspergillus niger was inoculated into a culture medium and cultured to obtain Aspergillus niger fermentation broth. The liquid part of the Aspergillus niger fermentation broth was extracted and collected. After separation and purification, fructosyltransferase from Aspergillus niger was obtained.
[0024] (2) Aspergillus oryzae was inoculated into a culture medium and cultured to obtain Aspergillus oryzae fermentation broth. The liquid part of the Aspergillus oryzae fermentation broth was extracted and collected. After separation and purification, the fructosyltransferase from Aspergillus oryzae was obtained.
[0025] (3) Mix the fructosyltransferase from Aspergillus niger obtained in step (1) with the fructosyltransferase from Aspergillus oryzae obtained in step (2) to obtain a mixed fructosyltransferase.
[0026] (4) After mixing sucrose with water, inoculate the mixed fructosyltransferase obtained in step (3) and ferment under anaerobic conditions to obtain a solution containing oligofructose.
[0027] (5) After separating, purifying and drying the solution containing oligofructose obtained in step (4), oligofructose is obtained.
[0028] In this invention, the culture medium in step (1) is PDA culture medium, which also contains CaCl2 at a concentration of 0.15-0.25 g / L, preferably at a concentration of 0.18-0.22 g / L, and more preferably at a concentration of 0.2 g / L; the culture temperature is 20-30°C, preferably 22-28°C, more preferably 24-26°C, and more preferably 25°C; the culture rate is 150-200 rpm, preferably 160-190 rpm, and more preferably 180 rpm; the culture time is 40-56 h, preferably 42-54 h, more preferably 44-52 h, and more preferably 48 h.
[0029] In this invention, the culture medium in step (2) is PDA culture medium; the culture temperature is 20-30℃, preferably 22-28℃, more preferably 24-26℃, more preferably 25℃, the culture rate is 150-200rpm, preferably 160-190rpm, more preferably 180rpm, and the culture time is 40-56h, preferably 42-54h, more preferably 44-52h, more preferably 48h.
[0030] In this invention, the separation and purification methods described in steps (1) and (2) are ammonium sulfate precipitation and ion exchange chromatography.
[0031] In this invention, the mass ratio of the fructosyltransferase from Aspergillus niger and the fructosyltransferase from Aspergillus oryzae in step (3) is 1.5-2.5:0.8-1.2.
[0032] In this invention, the concentration of sucrose after mixing sucrose and water in step (4) is 20-30%, preferably 22-28%, more preferably 24-26%, and even more preferably 25%; the concentration of the mixed fructosyltransferase is 400-600 U / mL, preferably 450-550 U / mL, and even more preferably 500 U / mL; the fermentation temperature is 40-60℃, preferably 45-55℃, and even more preferably 50℃, and the fermentation time is 20-30h, preferably 22-28h, even more preferably 24-26h, and even more preferably 25h.
[0033] In this invention, the separation and purification method in step (5) is the cation exchange resin method and the ultrafiltration method; the drying is spray drying, and the temperature of the spray drying is 160-170°C, preferably 165°C.
[0034] This invention provides an oligofructose prepared according to the method described above.
[0035] The present invention also provides an application of the aforementioned fructooligosaccharide in food preparation, the food including baked goods, confectionery and beverages.
[0036] Preferably, the food is a general food, functional food, health food, or infant formula that has the functions of enhancing immunity, regulating intestinal flora, promoting digestion and relieving constipation.
[0037] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0038] Example 1
[0039] A method for preparing oligofructose, comprising the following steps:
[0040] (1) The activated Aspergillus niger was prepared to a concentration of 1×10 6 The spore suspension of CFU / mL was inoculated into PDA medium containing 0.2 g / L CaCl2 at an inoculation rate of 5%, and cultured with shaking at 25℃ and 180 rpm for 48 h to obtain the Aspergillus niger fermentation broth.
[0041] (2) The Aspergillus niger fermentation culture obtained in step (1) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus niger was obtained.
[0042] (3) The activated Aspergillus oryzae was prepared to a concentration of 1×10 6 After mixing the CFU / mL spore suspension with equal volumes, the mixture was inoculated into PDA medium at a 5% inoculum and cultured with shaking at 25℃ and 180 rpm for 48 h to obtain Aspergillus oryzae fermentation broth.
[0043] (4) The Aspergillus fermentation culture broth obtained in step (3) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus oryzae was obtained.
[0044] (5) The fructosyltransferase from Aspergillus niger obtained in step (2) and the fructosyltransferase from Aspergillus oryzae obtained in step (4) are mixed at a mass ratio of 2:1 to obtain a mixed fructosyltransferase.
[0045] (6) Dissolve sucrose in ultrapure water to prepare a 25% dilute sugar solution. Inoculate the mixed fructosyltransferase obtained in step (5) into the dilute sugar solution. Adjust the concentration of fructosyltransferase to 500 U / mL. Ferment under anaerobic conditions at 40°C for 20 h to obtain a solution containing oligofructose.
[0046] (7) The solution containing oligofructose obtained in step (6) is first coarsely separated by cation exchange resin and the filtrate is collected. The collected filtrate is ultrafiltered with an ultrafiltration membrane (pore size of 0.005 μm), the filtrate is collected, and spray-dried at a temperature of 165°C to obtain oligofructose.
[0047] Example 2
[0048] A method for preparing oligofructose, comprising the following steps:
[0049] (1) The activated Aspergillus niger was prepared to a concentration of 1×10 6The spore suspension of CFU / mL was inoculated at a rate of 5% into PDA medium containing 0.15 g / L CaCl2 and cultured with shaking at 20℃ and 150 rpm for 40 h to obtain the Aspergillus niger fermentation broth.
[0050] (2) The Aspergillus niger fermentation culture obtained in step (1) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus niger was obtained.
[0051] (3) The activated Aspergillus oryzae was prepared to a concentration of 1×10 6 After mixing the CFU / mL spore suspension with equal volumes, the mixture was inoculated into PDA medium at a 5% inoculum and cultured with shaking at 20℃ and 150 rpm for 40 h to obtain the Aspergillus oryzae fermentation broth.
[0052] (4) The Aspergillus fermentation culture broth obtained in step (3) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus oryzae was obtained.
[0053] (5) The fructosyltransferase from Aspergillus niger obtained in step (2) and the fructosyltransferase from Aspergillus oryzae obtained in step (4) are mixed at a mass ratio of 1.5:1 to obtain a mixed fructosyltransferase.
[0054] (6) Dissolve sucrose in ultrapure water to prepare a 25% dilute sugar solution. Inoculate the mixed fructosyltransferase obtained in step (5) into the dilute sugar solution. Adjust the concentration of fructosyltransferase to 400 U / mL. Ferment under anaerobic conditions at 60°C for 30 h to obtain a solution containing oligofructose.
[0055] (7) The solution containing oligofructose obtained in step (6) is first coarsely separated by cation exchange resin and the filtrate is collected. The collected filtrate is ultrafiltered with an ultrafiltration membrane (pore size of 0.005 μm), the filtrate is collected, and spray-dried at a temperature of 165°C to obtain oligofructose.
[0056] Example 3
[0057] A method for preparing oligofructose, comprising the following steps:
[0058] (1) The activated Aspergillus niger was prepared to a concentration of 1×10 6The spore suspension of CFU / mL was inoculated at a rate of 5% into PDA medium containing 0.25 g / L CaCl2 and cultured with shaking at 30℃ and 200 rpm for 56 h to obtain the Aspergillus niger fermentation broth.
[0059] (2) The Aspergillus niger fermentation culture obtained in step (1) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus niger was obtained.
[0060] (3) The activated Aspergillus oryzae was prepared to a concentration of 1×10 6 After mixing the CFU / mL spore suspension with equal volumes, the mixture was inoculated into PDA medium at a 5% inoculum and cultured with shaking at 30℃ and 200 rpm for 56 h to obtain the Aspergillus oryzae fermentation broth.
[0061] (4) The Aspergillus fermentation culture broth obtained in step (3) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus oryzae was obtained.
[0062] (5) The fructosyltransferase from Aspergillus niger obtained in step (2) and the fructosyltransferase from Aspergillus oryzae obtained in step (4) are mixed at a mass ratio of 2.5:1 to obtain a mixed fructosyltransferase.
[0063] (6) Dissolve sucrose in ultrapure water to prepare a 25% dilute sugar solution. Inoculate the mixed fructosyltransferase obtained in step (5) into the dilute sugar solution. Adjust the concentration of fructosyltransferase to 600 U / mL. Ferment under anaerobic conditions at 50°C for 25 h to obtain a solution containing oligofructose.
[0064] (7) The solution containing oligofructose obtained in step (6) is first coarsely separated by cation exchange resin and the filtrate is collected. The collected filtrate is ultrafiltered with an ultrafiltration membrane (pore size of 0.005 μm), the filtrate is collected, and spray-dried at a temperature of 165°C to obtain oligofructose.
[0065] Comparative Example 1
[0066] A method for preparing oligofructose, comprising the following steps:
[0067] (1) The activated Aspergillus niger was prepared to a concentration of 1×10 6 The spore suspension of CFU / mL was inoculated into PDA medium at an inoculum of 5%, and cultured with shaking at 25℃ and 180 rpm for 48 h to obtain the Aspergillus niger fermentation broth.
[0068] (2) The Aspergillus niger fermentation culture obtained in step (1) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus niger was obtained.
[0069] (3) The activated Aspergillus oryzae was prepared to a concentration of 1×10 6 After mixing the CFU / mL spore suspension with equal volumes, the mixture was inoculated into PDA medium at a 5% inoculum and cultured with shaking at 25℃ and 180 rpm for 48 h to obtain Aspergillus oryzae fermentation broth.
[0070] (4) The Aspergillus fermentation culture broth obtained in step (3) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus oryzae was obtained.
[0071] (5) The fructosyltransferase from Aspergillus niger obtained in step (2) and the fructosyltransferase from Aspergillus oryzae obtained in step (4) are mixed at a mass ratio of 2:1 to obtain a mixed fructosyltransferase.
[0072] (6) Dissolve sucrose in ultrapure water to prepare a 25% dilute sugar solution. Inoculate the mixed fructosyltransferase obtained in step (5) into the dilute sugar solution. Adjust the concentration of fructosyltransferase to 500 U / mL. Ferment under anaerobic conditions at 40°C for 20 h to obtain a solution containing oligofructose.
[0073] (7) The solution containing oligofructose obtained in step (6) is first coarsely separated by cation exchange resin and the filtrate is collected. The collected filtrate is ultrafiltered with an ultrafiltration membrane (pore size of 0.005 μm), the filtrate is collected, and spray-dried at a temperature of 165°C to obtain oligofructose.
[0074] Comparative Example 2
[0075] A method for preparing oligofructose, comprising the following steps:
[0076] (1) The activated Aspergillus niger was prepared to a concentration of 1×10 6 The spore suspension of CFU / mL was inoculated into PDA medium containing 0.2 g / L CaCl2 at an inoculation rate of 5%, and cultured with shaking at 25℃ and 180 rpm for 48 h to obtain the Aspergillus niger fermentation broth.
[0077] (2) The Aspergillus niger fermentation culture obtained in step (1) was extracted by vacuum extraction, and the liquid part was collected to obtain crude enzyme solution. The solution containing fructosyltransferase was collected by ammonium sulfate precipitation method and ion exchange chromatography method. After freeze drying, fructosyltransferase from Aspergillus niger was obtained.
[0078] (3) Dissolve sucrose in ultrapure water to prepare a 25% dilute sugar solution. Inoculate the fructosyltransferase from Aspergillus niger prepared in step (2) into the dilute sugar solution. Adjust the concentration of fructosyltransferase to 500 U / mL. Ferment under anaerobic conditions at 40℃ for 20 h to obtain a solution containing oligofructose.
[0079] (4) The solution containing oligofructose obtained in step (3) is first coarsely separated by cation exchange resin and the filtrate is collected. The collected filtrate is ultrafiltered with an ultrafiltration membrane (pore size of 0.005 μm), the filtrate is collected, and spray-dried at a temperature of 165°C to obtain oligofructose.
[0080] Experimental Example 1
[0081] The purpose of this experiment is to determine the effects of the oligofructose prepared in Examples 1-3 and Comparative Examples 1-2 on the intestinal function of mice.
[0082] One hundred and forty Kunming mice were randomly divided into seven groups (blank control group, model control group, Example 1 group, Example 2 group, Example 3 group, Comparative Example 1 group, and Comparative Example 2 group), with twenty mice in each group. Except for the blank control group, the other six groups were administered loperamide hydrochloride once daily by gavage at a dose of 10 mg / kg for one week to establish a mouse constipation model.
[0083] The fructooligosaccharides prepared in Examples 1-3 and Comparative Examples 1-2 were mixed with distilled water at a mass-to-volume ratio of 1g:5mL to obtain gavage solutions. The gavage solutions prepared in Examples 1, 2, 3, Comparative Examples 1, and Comparative Examples 2 were administered to mice that successfully modeled the disease via gavage at a volume of 5mL / kg. The blank control group and the model control group were administered an equal volume of physiological saline via gavage. This gavage was continued for 14 days, during which all mice had free access to water and food. After 14 days of gavage, all mice were fasted for 12 hours (with no restriction on water) before the final gavage. Thirty minutes after the final gavage, all mice were administered an equal volume of activated charcoal via gavage. 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 activated charcoal was propelled was measured, and the small intestine propulsion rate (%) was calculated. The results are shown in Table 1.
[0084] Small intestinal propulsion rate = Activated carbon propulsion distance / Total small intestinal length × 100%
[0085] Table 1. Calculation results of small intestinal propulsion rate in mice of each group.
[0086]
[0087]
[0088] As shown in Table 1, the small intestinal propulsion rate of mice in the model control group was significantly lower than that in the blank control group, indicating that the mouse constipation model was successfully constructed. The small intestinal propulsion rate of mice in Examples 1-3 of this invention was significantly higher than that in Comparative Examples 1-2, with Example 1 showing the highest rate. This indicates that the fructooligosaccharides prepared in this invention have a more significant effect on promoting intestinal peristalsis and relieving constipation compared to Comparative Examples 1-2.
[0089] Experimental Example 2
[0090] The purpose of this experiment is to determine the effects of the oligofructose prepared in Examples 1-3 and Comparative Examples 1-2 on the intestinal flora of mice.
[0091] Sixty SPF mice were randomly divided into six groups of ten each. Five groups were fed with fructooligosaccharide solutions prepared in Examples 1-3 and Comparative Examples 1-2, respectively (fructooligosaccharide and distilled water were mixed at a mass-to-volume ratio of 1 g: 5 mL), while the other group was fed distilled water. Each group was fed 5 mL of distilled water daily for 14 days. Mice drank and ate normally during the feeding period. The gut microbiota counts were recorded after the feeding period, and the results are shown in Table 2.
[0092] Table 2. Statistical results of gut microbiota count in mice of each group (CFU / g)
[0093] Bifidobacteria Lactic acid bacteria Enterococcus Blank control <![CDATA[8.67×10 5 ]]> <![CDATA[1.04×10 7 ]]> <![CDATA[1.26×10 6 ]]> Example 1 <![CDATA[1.53×10 6 ]]> <![CDATA[1.42×10 7 ]]> <![CDATA[1.27×10 6 ]]> Example 2 <![CDATA[1.48×10 6 ]]> <![CDATA[1.37×10 7 ]]> <![CDATA[1.31×10 6 ]]> Example 3 <![CDATA[1.41×10 6 ]]> <![CDATA[1.31×10 7 ]]> <![CDATA[1.25×10 6 ]]> Comparative Example 1 <![CDATA[9.78×10 5 ]]> <![CDATA[1.23×10 7 ]]> <![CDATA[1.19×10 6 ]]> Comparative Example 2 <![CDATA[1.25×10 6 ]]> <![CDATA[1.22×10 7 ]]> <![CDATA[1.23×10 6 ]]>
[0094] As shown in Table 2, compared with the blank control group and comparative examples 1-2, feeding mice with the fructooligosaccharides prepared in Examples 1-3 of this invention can significantly increase the number of Bifidobacteria and Lactobacilli in the intestines. Among them, the effect of Example 1 in increasing the number of Bifidobacteria and Lactobacilli is the best, while it has no significant effect on the number of Enterococci. This indicates that the fructooligosaccharides prepared in this invention have the effect of improving the intestinal flora, and the improvement effect is better than that of comparative examples 1 and 2.
[0095] Experimental Example 3
[0096] The purpose of this experiment is to determine the effect of the oligofructose prepared in Examples 1-3 and Comparative Examples 1-2 on mineral absorption.
[0097] Sixty Kunming mice weighing between 18 and 22 g were randomly divided into 6 groups of 10 mice each. The control group was fed a basal diet; the other five groups were fed a basal diet and, in addition, were administered fructooligosaccharides prepared in Examples 1-3 and Comparative Examples 1-2 by gavage at a dose of 1 g / kg, once daily. The experiment lasted 21 days, during which the mice had free access to water and food. After the experiment, the mice were separated into different cages and allowed to acclimatize for 2 days. Feces were collected from 8:00 AM to 8:00 AM the following day for 3 consecutive days. The collected feces were digested, and the levels of Ca, Mg, and Fe in the digestive fluid were determined using atomic absorption spectrometry. The apparent mineral absorption rate was calculated, and the results are shown in Table 3.
[0098] Table 3. Calculation results of apparent mineral absorption rate in mice of each group.
[0099] Ca (%) Mg (%) Fe (%) control group 33.43 18.92 5.35 Example 1 Group 51.25 32.47 8.57 Example 2 group 48.27 31.39 8.36 Example 3 Group 46.81 30.70 8.21 Comparative Example 1 41.64 24.89 6.96 Comparative Example 2 42.02 25.23 7.32
[0100] As shown in Table 3, compared with the control group, the fructooligosaccharides prepared in Examples 1-3 and Comparative Examples 1-2 significantly improved the absorption rate of minerals in mice. Compared with Comparative Examples 1-2, the fructooligosaccharides prepared in Examples 1-3 had a stronger effect on promoting the absorption of minerals in mice. Among them, the fructooligosaccharide group in Example 1 had the best effect on promoting the absorption of minerals in mice, indicating that the fructooligosaccharides prepared in this invention have a significantly enhanced effect on promoting the absorption of minerals compared with the comparative examples.
[0101] In summary, the experimental results of Examples 1-3 show that the fructooligosaccharides prepared in this invention have good effects on promoting intestinal peristalsis, increasing the number of bifidobacteria and lactic acid bacteria in the intestine, and promoting the body's ability to absorb minerals. The fructooligosaccharides prepared in Example 1 showed the best effect. Compared with Comparative Example 1, the fructosyltransferase derived from Aspergillus niger obtained by culturing Aspergillus niger in PDA medium containing 0.2 g / L CaCl2 in Example 1 significantly improved the small intestinal propulsion rate in mice, increased the number of bifidobacteria and lactic acid bacteria in the mouse intestine, and promoted the absorption of minerals in mice, compared with the fructosyltransferase derived from Aspergillus niger obtained by directly culturing Aspergillus niger in PDA medium. This indicates that adding CaCl2 to the Aspergillus niger culture medium is beneficial to enhancing the catalytic performance of the fructosyltransferase derived from Aspergillus niger, thereby improving the effects of the prepared fructooligosaccharides on promoting intestinal peristalsis, increasing the number of bifidobacteria and lactic acid bacteria in the intestine, and promoting the body's ability to absorb minerals. Compared with Comparative Example 2, Example 1 also added fructosyltransferase from Aspergillus oryzae during the preparation of fructooligosaccharides. This significantly improved the effects of the prepared fructooligosaccharides on promoting intestinal peristalsis, increasing the number of Bifidobacteria and Lactobacilli in the intestine, and promoting the body's ability to absorb minerals. This indicates that the fructosyltransferase from Aspergillus niger and the fructosyltransferase from Aspergillus oryzae have a synergistic effect on promoting catalytic performance during the preparation of fructooligosaccharides.
[0102] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing oligofructose to improve gut health, characterized in that, Includes the following steps: (1) Aspergillus niger was inoculated into a culture medium and cultured to obtain Aspergillus niger fermentation broth. The liquid part of the Aspergillus niger fermentation broth was extracted and collected. After separation and purification, fructosyltransferase from Aspergillus niger was obtained. (2) Aspergillus oryzae was inoculated into a culture medium and cultured to obtain Aspergillus oryzae fermentation broth. The liquid part of the Aspergillus oryzae fermentation broth was extracted and collected. After separation and purification, the fructosyltransferase from Aspergillus oryzae was obtained. (3) Mix the fructosyltransferase from Aspergillus niger obtained in step (1) with the fructosyltransferase from Aspergillus oryzae obtained in step (2) to obtain a mixed fructosyltransferase. (4) After mixing sucrose with water, inoculate the mixed fructosyltransferase obtained in step (3) and ferment under anaerobic conditions to obtain a solution containing oligofructose. (5) After separating, purifying and drying the solution containing oligofructose obtained in step (4), oligofructose is obtained.
2. The method as described in claim 1, characterized in that, The culture medium mentioned in step (1) is PDA culture medium, which also contains CaCl2 at a concentration of 0.15 to 0.25 g / L; the culture temperature is 20 to 30°C, the rate is 150 to 200 rpm, and the time is 40 to 56 h.
3. The method as described in claim 2, characterized in that, The culture medium mentioned in step (2) is PDA culture medium; the culture temperature is 20-30℃, the rate is 150-200rpm, and the time is 40-56h.
4. The method as described in claim 3, characterized in that, The separation and purification methods described in steps (1) and (2) are ammonium sulfate precipitation and ion exchange chromatography.
5. The method as described in claim 4, characterized in that, The mass ratio of the fructosyltransferase from Aspergillus niger and the fructosyltransferase from Aspergillus oryzae in step (3) is 1.5-2.5:0.8-1.
2.
6. The method as described in claim 5, characterized in that, In step (4), the concentration of sucrose after mixing with water is 20-30%; the concentration of the mixed fructosyltransferase is 400-600 U / mL; the fermentation temperature is 40-60℃ and the time is 20-30h.
7. The method according to any one of claims 1 to 6, characterized in that, The separation and purification method described in step (5) is cation exchange resin method and ultrafiltration method; the drying is spray drying, and the spray drying temperature is 160-170℃.
8. A fructooligosaccharide prepared according to any one of claims 1 to 7.
9. The application of the fructooligosaccharide according to claim 8 in food preparation, characterized in that, The food products include baked goods, confectionery, and beverages.
10. The application as described in claim 9, characterized in that, The food mentioned is a general food, functional food, health food, or infant formula that has the functions of enhancing immunity, regulating intestinal flora, promoting digestion and relieving constipation.