Composition helpful for maintaining healthy level of blood sugar and application thereof

Abstract

The invention relates to the technical field of health-care products, in particular to a composition beneficial to maintaining the healthy level of blood sugar and application of the composition. The composition comprises rutin, quercetin and pectin. According to the composition, rutin, quercetin and pectin are compounded according to a certain proportion, and the obtained composition can effectively inhibit the activity of alpha-amylase and has a remarkable inhibiting effect on the digestion rate of starch and increase of the postprandial blood sugar level. The effect of the flavonoid mixture is better than that of single use of the flavonoid mixture. In addition, according to the composition prepared by the invention, the dosage of quercetin is reduced, the utilization rate of pectin is increased, the production cost is reduced, and a new thought is provided for development of functional food capable of reducing blood sugar.

Description

Technical Field

[0001] The present invention relates to the technical field of health food, and in particular to a composition and application thereof that helps maintain a healthy blood sugar level. Background Art

[0002] Diabetes has become the third largest chronic disease in the world after tumors and cardiovascular diseases. Its occurrence is mainly related to the disorder of sugar, protein and lipid metabolism caused by abnormal increase in blood sugar levels. Type 2 diabetes is the most common type of diabetes, accounting for more than 90% of diabetes cases worldwide. As a small intestinal digestive enzyme, α-amylase can act on the α-1,4-glycosidic bonds inside polysaccharides and hydrolyze them into oligosaccharides, maltose and a small amount of glucose. Therefore, by inhibiting the activity of α-amylase, starch digestion can be delayed and blood sugar levels in the body can be effectively regulated.

[0003] Flavonoids are a large class of phenolic substances widely present in nature, and are also a kind of plant secondary metabolite. They are widely distributed in the plant kingdom and exist in a variety of food-derived plants such as tea, flowers, beans, vegetables and fruits. As the extraction, separation and identification techniques of flavonoids become more mature, in addition to being used as natural pigments, they are also widely used as a type of food additive in the production of many types of food such as beverages, candies, liquor and chocolate. At the same time, flavonoids have antioxidant, antibacterial, antiviral, cardiovascular disease treatment, cancer prevention, and anti-inflammatory effects. Previously, the inventors found through research that rutin, quercetin and kaempferol can spontaneously bind to α-amylase through non-covalent interactions, change the structure and hydrophobic microenvironment of α-amylase, and thus effectively inhibit the activity of α-amylase.

[0004] However, the human dietary system is very complex, including not only flavonoids, but also polysaccharides, proteins and many other active substances. Among them, dietary fiber is known as the "seventh nutrient" and has been proposed as a candidate drug for the treatment of type 2 diabetes. Pectin is a soluble dietary fiber naturally present in fruits and vegetables. It is one of the components of plant cell walls and has been widely used in food processing. At present, there are no reports on the combination of pectin and flavonoids for hypoglycemic effect. Summary of the invention

[0005] In view of this, the present invention provides a composition and application thereof that helps maintain healthy blood sugar levels.

[0006] The composition comprises flavonoids and pectin in a mass ratio of (1.55-24.27):(1-15); the flavonoids comprise rutin and quercetin.

[0007] The present invention investigates the hypoglycemic effect of different flavonoids and pectin combined, and the results show that the composition composed of rutin, quercetin and pectin can effectively inhibit the activity of α-amylase, solving the problem of limited anti-starch digestion and hypoglycemic effect of single active ingredients in the prior art. Compared with the composition composed of other flavonoids and pectin, the hypoglycemic effect of the composition of the present invention is significantly improved, and the CI is less than 0.9. It shows that in the composition of the present invention, the three components of rutin, quercetin and pectin are reasonably matched, resulting in a synergistic hypoglycemic effect.

[0008] In the present invention, in the composition, the mass ratio of flavonoids to pectin is (3.10-12.38):(5-10), specifically 3.10:5, 3.10:10, 6.19:5, 6.19:10, 12.38:5, 12.38:10, or any value within the above two numerical ranges.

[0009] In the present invention, in the flavonoids, the mass ratio of rutin to quercetin is (4.89-78.20):(1.30-20.82), specifically 4.89:1.30, 9.78:2.60, 19.55:5.21, 39.10:10.41, 78.20:20.82 or any value within the above two numerical ranges.

[0010] In the present invention, the composition further comprises a buffer. In some embodiments, the buffer comprises a sodium phosphate buffer, a potassium phosphate buffer, a potassium phosphate buffer, a sodium acetate buffer or a potassium acetate buffer. In some specific embodiments, the buffer is a phosphate buffer. In some embodiments, the concentration of the buffer is 0.1M to 0.3M, specifically 0.1M, 0.2M, 0.3M. In some embodiments, the pH of the buffer is 6.0 to 8.0, specifically 6.0, 6.5, 7.0, 7.5, 8.0.

[0011] In the present invention, "composition" is not limited to the physical mixture of active ingredients in the composition, but also includes the combination of active ingredients in any order at a certain time interval. Specifically, in the present invention, the composition is a combination of flavonoids and pectin in the prevention and treatment of diabetes or maintenance of healthy blood sugar levels, and the two can exist in a mixed form or separately.

[0012] The present invention also provides a method for preparing the composition, comprising: dissolving the pectin and the flavonoid mixture in a phosphate buffer respectively, or dissolving the pectin and / or the flavonoid substance in a phosphate buffer simultaneously.

[0013] The present invention also provides application of the composition in preparing products that are helpful in maintaining healthy blood sugar levels.

[0014] In the application of the present invention, maintaining a healthy blood sugar level includes: inhibiting α-amylase activity, reducing RDS content, increasing RS content and / or increasing SDS content.

[0015] In the present invention, when the composition of the present invention is used to inhibit α-amylase or to maintain a healthy blood sugar level, the flavonoids and pectin can be used simultaneously or in any order. When the two are used simultaneously, there are two situations: the flavonoids and pectin are present in a mixed form, or the flavonoids and pectin are present independently and then used simultaneously. Experiments show that whether the two are used simultaneously or in different orders, they have a significant inhibitory effect on the activity of α-amylase.

[0016] The invention also provides application of the composition in preparing alpha-amylase inhibitors.

[0017] The present invention also provides a product for maintaining healthy blood sugar level, which comprises the composition of the present invention.

[0018] In the present invention, the product includes health food or food.

[0019] In the present invention, the dosage form of the product includes tablets, syrups, granules, oral liquids, pills, capsules or drop pills.

[0020] The present invention also provides a method for maintaining healthy blood sugar levels, comprising: administering the composition or product of the present invention.

[0021] The present invention provides a composition that helps maintain a healthy blood sugar level and its application. The composition includes rutin, quercetin and pectin. The present invention compounds rutin, quercetin and pectin in a certain ratio, and the obtained composition can effectively inhibit the activity of α-amylase, and has a significant inhibitory effect on the digestion rate of starch and the increase of blood sugar level after a meal. Its effect is better than using the flavonoid mixture alone. In addition, the composition prepared by the present invention reduces the amount of quercetin, increases the utilization rate of pectin, reduces the production cost, and provides a new idea for the development of functional foods with blood sugar reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the inhibition rate of flavonoid monomers on α-amylase activity;

[0023] Figure 2 is the CI value of different combinations of flavonoids for inhibiting α-amylase activity;

[0024] Figure 3 is the inhibition rate of different flavonoid compositions on α-amylase activity in the presence of pectin;

[0025] Table 1 shows the CI values ​​of the pectin-flavonoid composition for inhibiting α-amylase;

[0026] Figure 4 Inhibition rate of α-amylase activity by pectin-rutin-quercetin mixture under different addition orders;

[0027] Figure 5 are the digestion and hydrolysis curves of starch in the presence and absence of pectin and rutin-quercetin mixture;

[0028] Figure 6 is the digestible fragment content of starch in the presence or absence of pectin and rutin-quercetin mixture;

[0029] Figure 7 Changes in postprandial blood glucose levels in mice in the presence or absence of pectin and rutin-quercetin mixture. DETAILED DESCRIPTION

[0030] The present invention provides a composition and its application that helps maintain healthy blood sugar levels. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It is particularly important to point out that all similar replacements and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0031] The α-amylase inhibitory activity determination method involved in the embodiments of the present invention is:

[0032] 500 μL of sample solutions of different concentrations and 250 μL of α-amylase (7 U / mL) solution were incubated at 37°C for 20 min. Then 500 μL of gelatinized soluble starch solution (10 mg / mL) was added to the reaction mixture and incubated at 37°C for 8 min. After the reaction was completed, 1 mL of DNS reagent was quickly added to terminate the reaction, and the reaction product was heated in boiling water for 8 min. After cooling to room temperature, the volume was made up to 25 mL with deionized water. Finally, the absorbance of the solution at 540 nm was recorded using a spectrophotometer. Phosphate buffer (0.2 mol / L) was used as a blank control. The calculation formula (1) for the inhibition rate of α-amylase is as follows:

[0033]

[0034] Wherein, A, B, C, and D represent the absorbance values ​​of sample, sample blank, control, and control blank, respectively.

[0035] The combined inhibition assay method of α-amylase involved in the embodiments of the present invention is as follows:

[0036] A series of sample solutions with different ratios were prepared using phosphate buffer (0.2 mol / L, pH 6.9) as solvent. The concentration ratio of the fixed sample in the reaction system was IC 50 The effect of the sample on α-amylase (F a )-combination index (CI) relationship, evaluating the combined inhibition of samples on α-amylase. All CI values ​​are in F a Range(0 <F a Among them, CI<0.9, CI=0.9-1.1 and CI>1 represent synergistic effect, additive effect and antagonistic effect, respectively.

[0037] The method for determining the hydrolysis rate and digestion fragment content of starch in vitro digestion involved in the embodiments of the present invention is as follows:

[0038] Dissolve 10 mg / mL of cassava starch in sodium acetate buffer solution (0.2 mol / L), gelatinize at 90°C for 20 min, and store at 37°C for later use. Thoroughly mix 0.75 mL of sample solution of different concentrations and 1.25 mL of mixed enzyme solution (290 U / mL α-amylase and 60 U / mL α-glucosidase) and incubate at 37°C for 20 min. Sodium acetate buffer solution was used as a control. Add 1.8 mL of gelatinized starch to the above reaction solution and oscillate in a 37°C constant temperature water bath at a speed of 150 r / min. Take 150 μL of the reaction solution at 0, 20, 40, 60, 90, 120 and 180 min and add it to a 1.5 mL test tube containing 300 μL of 0.3 M Na2CO3 to stop the reaction. Then, centrifuge the reaction solution at 7300 rpm for 5 min, and the supernatant and precipitate are both for later use. Then, 100 μL of the supernatant was added with 3 mL of GOPOD reagent and placed in a water bath at 50°C for 20 min. The absorbance of each sample was measured at 510 nm. 100 μL of 1 mg / mL glucose solution was used as the standard sample. The calculation formulas (2)-(5) for the hydrolysis rate and digestion fragment content of starch are as follows:

[0039]

[0040] RS(%)=(1-RDS-SDS)×100% (Formula 5)

[0041] Among them, G t represents the glucose content in the sample at time t; RDS represents the rapidly digestible starch content, %; SDS represents the slowly digestible starch content, %; RS represents the resistant starch content, %; G0 represents the amount of free glucose before enzymatic hydrolysis, mg; G 20 Indicates the amount of glucose produced after 20 minutes of enzymatic hydrolysis, mg; G120 It represents the amount of glucose produced after hydrolysis for 120 min, mg; S represents the total starch content in the sample, mg.

[0042] The method for determining the postprandial blood sugar response involved in the embodiments of the present invention is as follows:

[0043] Four-week-old male golden hamsters (initial body weight: 75-85g) were purchased and raised in an SPF animal room (temperature: 24±2°C; relative humidity: 55±5% humidity; 12h light / dark cycle), 6 per cage, fed with ordinary feed, and allowed to eat and drink freely. After one week of adaptive feeding, the mice were divided into 4 groups (n=5) according to their body weight, and each group of mice was fasted for 18h. Then, the fasted mice were given physiological saline (100mL / kg body weight (BW)), flavonoid mixture samples (100mg / kgBW) and flavonoid mixture-pectin samples (100mg / kg BW~200mg / kg BW, 100mg / kgBW~300mg / kg BW) separately by feeding. After about 30min of feeding, each mouse was given a cassava starch sample (2g / kg BW) by gavage. Blood samples were collected from the lateral tail vein at 0, 30, 60 and 120 min after gavage. Blood glucose levels were measured by glucometer.

[0044] To further illustrate the present invention, a composition for regulating starch digestion and blood sugar level by inhibiting α-amylase activity provided by the present invention is described in detail below with reference to examples.

[0045] The test materials used in the present invention are all common commercial products and can be purchased in the market.

[0046] The present invention will be further described below in conjunction with embodiments:

[0047] Example 1

[0048] Rutin and quercetin were dissolved in phosphate buffer (0.2 M, pH 6.9) and mixed in different proportions. The concentration gradient of the rutin and quercetin mixture was set at IC 50 The value is based on 1 / 8IC 50 、1 / 4IC 50 、1 / 2IC 50 、IC 50 and 2IC 50 That is, the concentration ratios of rutin to quercetin are 4.89 mg / mL: 1.30 mg / mL, 9.78 mg / mL: 2.60 mg / mL, 19.55 mg / mL: 5.21 mg / mL, 39.10 mg / mL: 10.41 mg / mL, and 78.20 mg / mL: 20.82 mg / mL.

[0049] 500 μL of rutin-quercetin mixture was mixed with 250 μL of α-amylase solution and incubated at 37°C for 20 min. The inhibitory ability of the mixture on α-amylase activity was measured and the CI value was calculated.

[0050] Comparative Example 1

[0051] Rutin was dissolved in phosphate buffer (0.3 M, pH 6.5).

[0052] 500 μL of rutin solution with different concentrations (8, 16, 24, 32, 40 mg / mL) was mixed thoroughly with 250 μL of α-amylase solution (7 U / mL), and then incubated at 37°C for 20 min to measure its inhibitory ability on α-amylase activity.

[0053] Comparative Example 2

[0054] Quercetin was dissolved in phosphate buffer (0.2 M, pH 7.5) to obtain a quercetin solution.

[0055] 500 μL of quercetin solution with different concentrations (1, 5, 10, 15, 20 mg / mL) was mixed thoroughly with 250 μL of α-amylase solution (7 U / mL), and then incubated at 37°C for 25 min to measure its inhibitory ability on α-amylase activity.

[0056] Comparative Example 3

[0057] Kaempferol was dissolved in phosphate buffer (0.2 M, pH 6.9) to obtain a kaempferol solution.

[0058] 500 μL of kaempferol solution of different concentrations (0.0625, 0.125, 0.25, 0.5, 1 mg / mL) was mixed thoroughly with 250 μL of α-amylase solution (7 U / mL), and then incubated at 37°C for 15 min to measure its inhibitory ability on α-amylase activity.

[0059] Comparative Example 4

[0060] Rutin and kaempferol were dissolved in phosphate buffer (0.2 M, pH 6.9) and mixed in different proportions. The concentration gradient of the rutin and kaempferol mixture was set at IC 50 The value is based on 1 / 8IC 50 、1 / 4IC 50 、1 / 2IC 50 、IC 50 and 2IC 50That is, the concentration ratios of rutin and kaempferol are 4.89:0.02, 9.78:0.04, 19.55:0.09, 39.10:0.17, and 78.20:0.34, respectively. 500 μL of rutin-kaempferol mixture was fully mixed with 250 μL of α-amylase solution, and then incubated at 37°C for 20 min to measure its inhibitory ability on α-amylase activity and calculate the CI value.

[0061] Comparative Example 5

[0062] Quercetin and kaempferol were dissolved in phosphate buffer (0.3 M, pH 7.5) and mixed in different proportions. The concentration gradient of the quercetin and kaempferol mixture was set at IC 50 The value is based on 1 / 8IC 50 、1 / 4IC 50 、1 / 2IC 50 、IC 50 and 2IC 50 That is, the concentration ratios of quercetin and kaempferol are 1.30:0.02, 2.60:0.04, 5.21:0.09, 10.41:0.17, and 20.82:0.34, respectively. 500 μL of the quercetin-kaempferol mixture was fully mixed with 250 μL of α-amylase solution and incubated at 37°C for 25 min to measure its inhibitory ability on α-amylase activity and calculate the CI value.

[0063] The experimental results obtained in Example 1 and Comparative Examples 1 to 5 are as follows Figure 1 and Figure 2 As shown. Figure 1 It can be seen that rutin, quercetin and kaempferol can effectively inhibit the activity of α-amylase, and as the concentration of flavonoids increases, the activity of α-amylase gradually decreases. Figure 2It can be seen that the combined inhibition of α-amylase by different combinations of flavonoids showed a dose-dependent change. At low concentrations, the mixture of rutin and kaempferol had a synergistic effect on the inhibition of α-amylase, and at higher concentrations, the two showed antagonism. The CI values ​​of the mixture of quercetin and kaempferol were 1.576±0.007, 1.400±0.007, 1.394±0.016, 1.616±0.009 and 1.593±0.013 at concentration ratios of 1.30:0.02, 2.60:0.04, 5.21:0.09, 10.41:0.17 and 20.82:0.34, respectively, and all were greater than 1.1, indicating that the combined use of the two had a strong antagonistic effect. Compared with other combinations, the CI values ​​of the mixture of rutin and quercetin at different concentration ratios (4.89:1.30, 9.78:2.60, 19.55:5.21, 39.10:10.41, 78.20:20.82) were all less than 0.9, indicating that the combined use of rutin and quercetin had the strongest synergistic effect on the inhibition of α-amylase.

[0064] Comparative Example 6

[0065] Rutin and kaempferol were dissolved in phosphate buffer (0.2M, pH 6.9) at a concentration ratio of 4.89:0.02, 9.78:0.04, and 19.55:0.09 to obtain different rutin-kaempferol mixed solutions, referred to as RK solutions. 1.25 mL of pectin solution (referred to as P) (4 mg / mL, dissolved in 0.2M pH 6.9 phosphate buffer) was incubated with 0.5 mL of RK solution at 37°C for 20 min to obtain RKP solution. Among them, the concentration ratios of rutin-kaempferol and pectin were 2.46:5, 2.46:10, 4.91:5, 4.91:10, 9.82:5, and 9.82:10. Incubate at 37°C for 15 min. Then, 0.25 mL of α-amylase (7 U / mL) solution was added, and the mixture was incubated at 37° C. for 20 min before its inhibitory ability on α-amylase activity was measured.

[0066] Comparative Example 7

[0067] Quercetin and kaempferol were dissolved in phosphate buffer (0.3M, pH 7.5) at a concentration ratio of 1.30:0.02, 2.60:0.04, and 5.21:0.09 to obtain different quercetin-kaempferol mixed solutions, referred to as QK solutions. 1.25 mL of pectin solution (referred to as P) (4 mg / mL, dissolved in 0.2 M pH 7.5 phosphate buffer) was incubated with 0.5 mL of QK solution at 37°C for 20 min to obtain QKP solution. Among them, the concentration ratios of quercetin-kaempferol and pectin were 0.66:5, 0.66:10, 1.32:5, 1.32:10, 2.65:5, and 2.65:10. Then, 0.25 mL of α-amylase (7 U / mL) solution was added, and the mixture was incubated at 37° C. for 25 min, and then the inhibitory ability on α-amylase activity was measured.

[0068] Example 2

[0069] Rutin and quercetin were dissolved in phosphate buffer (0.2M, pH 6.9) at a concentration ratio of 4.89:1.30, 9.78:2.60 and 19.55:5.21 to obtain different rutin-quercetin solutions (abbreviated as RQ). 1.25 mL of pectin solution (abbreviated as P) (4 mg / mL-8 mg / mL, dissolved in 0.2M pH 6.9 phosphate buffer) was incubated with 0.5 mL of RQ solution at 37°C for 20 min to obtain a phosphate buffer containing the composition of the present invention (RQP). Among them, the concentration ratios of rutin-quercetin and pectin were 3.10:5, 3.10:10, 6.19:5, 6.19:10, 12.38:5, and 12.38:10. Then, 0.25 mL of α-amylase (7 U / mL) solution was added, and the mixture was incubated at 37° C. for 15 min. The inhibitory ability of RQP on α-amylase activity was measured.

[0070] Example 3

[0071] Rutin and quercetin were dissolved in phosphate buffer (0.2M, pH 6.9) at a concentration ratio of 4.89:1.30, 9.78:2.60 and 19.55:5.21. 0.5 mL of the rutin-quercetin mixture was incubated with 0.25 mL of α-amylase solution at 37°C for 20 min. Then, 1.25 mL of pectin (4 mg / mL-8 mg / mL, dissolved in 0.2M pH 6.9 phosphate buffer) was added, wherein the concentration ratios of rutin-quercetin and pectin were 3.10:5, 3.10:10, 6.19:5, 6.19:10, 12.38:5, 12.38:10. Finally, after incubation at 37°C for 10 min, the inhibitory ability on α-amylase activity was measured.

[0072] The experimental results obtained in Examples 2 to 3 and Comparative Examples 6 to 7 are as follows Figure 3 and Figure 4 As shown. Figure 3 It can be seen that pectin significantly increased the degree of inhibition of α-amylase by different flavonoid combinations (P<0.05), and the inhibition rate increased in a dose-dependent manner with the increase in pectin concentration. Among the three combinations of pectin-flavonoid mixtures, the CI value of the pectin-rutin-quercetin mixture for inhibiting α-amylase was the lowest (Table 1), indicating that the combined inhibitory effect of pectin and rutin-quercetin mixture on α-amylase was the strongest. Figure 4 It can be seen that compared with sequence 1 (mixing the mixture of rutin-quercetin with pectin before adding α-amylase), sequence 2, that is, when the mixture of rutin-quercetin is first mixed with α-amylase and then pectin is added, the inhibitory ability of α-amylase is also significantly enhanced (P<0.05), but slightly lower than sequence 1. This shows that under sequence 1, the combination of pectin and rutin-quercetin mixture has the strongest inhibitory effect on α-amylase.

[0073] Table 1 shows the CI values ​​of pectin-flavonoid compositions for inhibiting α-amylase

[0074]

[0075] Note: R, Q and K stand for rutin, quercetin and kaempferol respectively, and P stands for pectin.

[0076] Comparative Example 8

[0077] 1.95 mL of sodium acetate buffer solution (0.2 mol / L, pH 5.4) and 1.25 mL of mixed enzyme solution were thoroughly mixed. The hydrolysis rate and digestion fragment content of the samples at different time periods were measured.

[0078] Comparative Example 9

[0079] Take 1.20mL of sodium acetate buffer solution (0.2mol / L, pH 5.4) and 0.75mL of rutin-quercetin mixture (concentration ratio of 39.10:10.41) and incubate at 37℃ for 20min. Add 1.25mL of mixed enzyme solution (290U / mL α-amylase and 60U / mL α-glucosidase) and mix thoroughly, and continue incubation at 37℃ for 20min. Determine the hydrolysis rate and digestion fragment content of the samples at different time periods.

[0080] Example 4

[0081] The mixture of rutin and quercetin was dissolved in sodium acetate buffer (0.2 mol / L, pH 5.2) at a concentration ratio of 39.10:10.41. 1.20 mL of pectin solution (2.5 mg / mL, dissolved in 0.2 M pH 5.2 sodium phosphate buffer) and 0.75 mL of rutin-quercetin mixture were incubated at 37°C for 10 min. 1.25 mL of mixed enzyme solution (290 U / mL α-amylase and 60 U / mL α-glucosidase) was added and mixed thoroughly, and the mixture was incubated at 37°C for another 20 min. The hydrolysis rate and digestion fragment content of the samples were determined at different time periods.

[0082] Example 5

[0083] The mixture of rutin and quercetin was dissolved in sodium acetate buffer (0.3 mol / L, pH 5.4) at a concentration ratio of 39.10:10.41. 1.20 mL of pectin solution (5 mg / mL, dissolved in 0.3 M pH 5.4 sodium phosphate buffer) and 0.75 mL of rutin-quercetin mixture were incubated at 37°C for 15 min. 1.25 mL of mixed enzyme solution (290 U / mL α-amylase and 60 U / mL α-glucosidase) was added and mixed thoroughly, and incubated at 37°C for another 20 min. The hydrolysis rate and digestion fragment content of the samples at different time periods were determined.

[0084] Example 6

[0085] The mixture of rutin and quercetin was dissolved in sodium acetate buffer (0.2 mol / L, pH 5.6) at a concentration ratio of 39.10:10.41. 1.20 mL of pectin solution (10 mg / mL, dissolved in 0.2 M pH 5.6 sodium phosphate buffer) and 0.75 mL of rutin-quercetin mixture were incubated at 37°C for 20 min. 1.25 mL of mixed enzyme solution (290 U / mL α-amylase and 60 U / mL α-glucosidase) was added and mixed thoroughly, and incubated at 37°C for another 20 min. The hydrolysis rate and digestion fragment content of the samples were measured at different time periods.

[0086] The effects of Examples 4 to 6 and Comparative Examples 8 to 9 on starch hydrolysis rate and digestion fragment content are shown in Table 1. Figure 5 and Figure 6 As shown. Figure 5 It can be seen that after adding the rutin-quercetin mixture, the hydrolysis rate of starch at 180 min decreased to 58.03%. After adding pectin, the inhibitory effect of the rutin-quercetin mixture on the hydrolysis rate of starch further increased, and the pectin concentration was negatively correlated with the hydrolysis rate. Figure 6It can be seen that after adding rutin-quercetin mixture, the RDS content of starch decreased from 49.27% ​​to 43.85%, and the RS content increased from 42.17% to 46.37%. Compared with the rutin-quercetin mixture, the combined use of pectin and rutin-quercetin mixture further reduced the RDS content and increased the RS content and SDS content. And the change in the content of digestible fragments of starch was dose-dependent with the pectin concentration. Among them, when the pectin concentration was 10 mg / mL, the RDS, SDS and RS contents were 24.60%, 13.59% and 61.81%, respectively. Compared with the use of rutin-quercetin mixture alone, RDS decreased by 43.90%, and the SDS and RS contents increased by 28.04% and 24.98%.

[0087] Comparative Example 10

[0088] Each mouse was given a sample of cassava starch (2 g / kg BW) by gavage. Blood samples were collected from the lateral tail vein at 0, 30, 60 and 120 minutes after gavage to measure blood glucose levels.

[0089] Comparative Example 11

[0090] Mice were fed a mixture of rutin and quercetin (100 mg / kg BW, concentration ratio of IC 50 The ratio of 1:1 was 39.10:10.41, and about 30 minutes later, each mouse was given a cassava starch sample (2 g / kg BW) by gavage. Blood samples were collected from the lateral tail vein at 0, 30, 60 and 120 minutes after gavage to measure blood glucose levels.

[0091] Example 7

[0092] Mice were fed a rutin-quercetin mixture (100 mg / kg BW) to a pectin sample (200 mg / kg BW), and about 30 minutes later, each mouse was given a cassava starch sample (2 g / kg BW) by gavage. Blood samples were collected from the lateral tail vein at 0, 30, 60, and 120 minutes after gavage to measure blood glucose levels.

[0093] Example 8

[0094] Mice were fed a mixture of rutin-quercetin (100 mg / kg BW) and pectin samples (300 mg / kg BW), and about 30 minutes later, each mouse was given a sample of cassava starch (2 g / kg BW) by gavage. Blood samples were collected from the lateral tail vein at 0, 30, 60, and 120 minutes after gavage to measure blood glucose levels.

[0095] The experimental results obtained in Examples 7 to 8 and Comparative Examples 10 to 11 are as follows Figure 7 shown.

[0096] Among them, the blank control group was given the cassava starch sample of Comparative Example 10.

[0097] RQ group: the sample of Comparative Example 11 was given.

[0098] R-Q+200 mg / kg BWP group: given the sample of Example 7.

[0099] R-Q+300 mg / kg BWP group: given the sample of Example 8.

[0100] It can be found that the postprandial blood glucose level of mice after starch feeding reaches the highest peak at 30min, which is 288.7mg / dL, and then gradually decreases, and the blood glucose level at 60min is 213.4mg / dL. After feeding with rutin-quercetin mixture (Comparative Example 11, RQ group), the postprandial blood glucose level of mice at 30min and 60min respectively drops to 282.4mg / dL and 205.3mg / dL. When rutin-quercetin mixture and pectin of different proportions are co-administered (Examples 7-8, R-Q+P group), the postprandial blood glucose level of mice is further reduced. Among them, when the addition amount of pectin is 300mg / kg BW (R-Q+300mg / kg BWP group), the postprandial blood glucose level of mice at 30min and 60min can reach 261.0mg / dL and 179.7mg / dL. This indicates that, compared with the rutin-quercetin mixture, the co-administration of the rutin-quercetin mixture of the present invention with pectin in different ratios helps to significantly improve the postprandial blood sugar level.

[0101] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A composition, characterized in that It includes flavonoids and pectin in a mass ratio of (1.55-24.27):(1-15); The flavonoids include rutin and quercetin.

2. The composition according to claim 1, characterized in that The mass ratio of the flavonoids to pectin is (3.10-12.38):(5-10).

3. The composition according to claim 1 or 2, characterized in that The mass ratio of rutin to quercetin is (4.89-78.20):(1.30-20.82).

4. The composition according to claim 1, characterized in that It also includes a buffer solution with a pH of 6.0 to 8.0 and a 0.1 to 0.3 M buffer solution; the buffer solution includes a sodium phosphate buffer solution, a potassium phosphate buffer solution, a potassium phosphate buffer solution, a sodium acetate buffer solution or a potassium acetate buffer solution.

5. The method for preparing the composition according to any one of claims 1 to 4, characterized in that: The pectin and flavonoid mixture was dissolved in phosphate buffer.

6. Use of the composition according to any one of claims 1 to 4 in the preparation of a product that helps maintain healthy blood sugar levels.

7. The use according to claim 6, characterized in that: The maintaining of healthy blood sugar level includes: inhibiting α-amylase activity, reducing RDS content, increasing RS content and / or increasing SDS content.

8. Use of the composition according to any one of claims 1 to 4 in the preparation of an α-amylase inhibitor.

9. A product, characterized in that A composition comprising any one of claims 1 to 4.

10. The product according to claim 9, wherein the product comprises a health food or a food, and the dosage form thereof comprises tablets, syrups, granules, oral liquids, pills, capsules or drop pills.

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