CN111617262A - A kind of starch-based colon-targeted controlled-release crystal inclusion compound and preparation method thereof - Google Patents

Abstract

The invention discloses a starch-based colon-targeted controlled-release crystal inclusion compound and a preparation method thereof. The preparation method performs gelatinization, complete enzymatic debranching of native starch, and alcohol precipitation and grading to obtain spiral dextrin, completely dissolving the obtained spiral dextrin, cooling to 80-100 DEG C, and adding nitrogen under the condition that nitrogen is passed through the whole process to isolate oxygen. The fat-soluble nutrient ethanol solution preheated to 80-100 ℃, stirred at constant temperature, after the reaction is completed, the mixed solution is slowly cooled to room temperature for 5-7 days at a cooling rate of 0.49-0.59 ℃/h. In the present invention, co-crystallization and precipitation of the spirodextrin/fat-soluble nutrient inclusion complex is carried out for the first time by the co-crystallization technology, and the inclusion complex can resist the digestion and absorption of the stomach and the small intestine, and realize the targeted release of the fat-soluble nutrients in the colon. The invention uses natural polysaccharide macromolecule as raw material, is cheap and easy to obtain, has good biocompatibility, broadens the application field of starch, and has important application value in colon-targeted controlled release carrier.

Description

A kind of starch-based colon-targeted controlled-release crystal inclusion compound and preparation method thereof

technical field

The invention belongs to the field of colon targeted delivery of functional active substances by natural macromolecular materials, and specifically relates to a preparation method of a starch-based colon targeted controlled-release crystal inclusion complex.

Background technique

In recent years, in the field of polymer research, the slow and controlled release materials of polymer functional active substances have become one of the most popular research topics, and the slow and controlled release technology has developed rapidly in the scientific field, involving many chemical, material, biological and other fields. In the field, sustained and controlled release technology can deliver functional active substances to specific target organs, improve their stability, improve bioavailability, and reduce their toxic and side effects on basal organs. In the sustained and controlled release system, the carrier material plays a key role, which is an important factor to endow the system with a specific function, and determines the sustained release effect of the functional active substance in the body. The research on natural polymer polysaccharide-starch slow-release material not only broadens the application field of starch, but also has important significance in food and medical applications.

As a natural polymer compound, starch occupies a very important position in renewable resources. It is cheap and easy to obtain, pollution-free and has good biocompatibility. Especially after specific structural reorganization or modification, starch derivatives with specific functions can be obtained. Domestic and foreign studies have shown that amylose can incorporate inorganic and organic small molecules, but the amylose used to encapsulate guest molecules in domestic and foreign research is extracted from native starch, and the preparation method not only uses organic compounds Such as n-butanol, isoamyl alcohol, etc., and the process of preparing amylose has low efficiency, high energy consumption and low embedding efficiency. The previous research of our research group found that a kind of amylose-like starch-spirodextrin with a narrow and concentrated range of polymerization degree distribution was obtained by using homogeneous enzymatic debranching and synergistic alcohol precipitation technology. Confirmation of Pingping Wang, Xinsheng Qin, Qingyu Yang, ZhigangLuo, Zhigang Xiao, and XichunPeng.Comparative StructuralCharacterization of Spiral Dextrin Inclusion Complexes with Vitamin E or SoyIsoflavone.Journal of Agricultural and Food Chemistry, 2017,65,8744-8753). Existing studies have shown that using its cavity structure of "inner and outer affinity", spirodextrin can form a V-shaped crystal structure with fat-soluble nutrients after inclusion at 40-60°C and after cooling in a refrigerator at 4°C overnight. Inclusion complex, because the V-type inclusion complex is resistant to acid hydrolysis by gastric acid and is easily hydrolyzed by pancreatic enzymes in the small intestinal juice, it can protect the fat-soluble nutrients in gastric juice and release them all in the small intestine, so that it can be used as An excellent carrier material for sustained and controlled release in the upper gastrointestinal tract.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the problems existing in the prior art, and to provide a starch-based colon-targeted controlled-release crystal inclusion compound and a preparation method thereof. The obtained inclusion compound has colon-targeted release performance, and the release rate of fat-soluble nutrients in the small intestine is not high. More than 20% can be used in the prevention and treatment of colon diseases.

Fat-soluble nutrients are functional factors that can effectively prevent and treat cardiovascular and cerebrovascular diseases, hypertension and other chronic diseases, and some of them need to be absorbed in the upper gastrointestinal tract. However, fat-soluble nutrients such as resveratrol, vitamin D3, β-carotene, etc., which have a strong effect on the prevention and treatment of colitis and other lower gastrointestinal diseases, have strong biological activity, However, its water solubility is poor, its properties are unstable, and its metabolism is rapid. The bioavailability of this nutrient orally is almost zero. Especially, this kind of nutrient needs to overcome the digestion of the upper gastrointestinal tract and enter the colon to exert its effect. Therefore, if the structure of the inclusion complex between spirodextrin and fat-soluble nutrients can be re-regulated and the inclusion complex is prepared into a colon-targeted controlled release system of fat-soluble nutrients, it can not only improve the stability and bioavailability of fat-soluble nutrients, but also improve the stability and bioavailability of fat-soluble nutrients. Targeted delivery of fat-soluble nutrients to the colon to exert antioxidant and anti-inflammatory effects, effectively prevent colitis and some colon diseases, and significantly expand the application scope of starch.

The invention adopts an in vitro simulated digestive system to explore the anti-digestion ability of the crystal inclusion complex in gastric juice and small intestinal juice, and monitors the enzymatic hydrolysis rate of spirodextrin and the release rate of fat-soluble nutrients in the digestion process. The spirodextrin/fat-soluble nutrient crystal inclusion compound obtained by the preparation method of the present invention breaks through the characteristics of the previously studied spirodextrin/fat-soluble nutrient inclusion compound that can only transport nutrients to the small intestine and is completely released in the small intestine. The dextrin/fat-soluble nutrient crystal inclusion complex can target and deliver fat-soluble nutrients to the colon to exert antioxidant and anti-inflammatory effects, and effectively prevent and treat colon-related diseases.

The object of the present invention is achieved through the following technical solutions:

A preparation method of a starch-based colon-targeted controlled-release crystal inclusion compound, comprising the following steps:

(1) The starch raw material is made into starch milk with a mass percentage concentration of 5% to 10%, and placed in a closed container for gelatinization under stirring at 100 to 150 ° C for 60 to 80 minutes;

(2) Cool the gelatinized liquid obtained in step (1), add debranching enzyme, and the dosage is 7.5-25 U per gram of dry starch, and stir and react at 45-60° C. for 10-12 hours; dextrin debranching Complete, inactivated enzyme, cooled to obtain debranched dextrin solution;

(3) placing the debranching dextrin solution in step (2) in a rotary evaporator for concentration, and precipitating the debranching dextrin in the concentrated solution; after centrifugal drying the debranching dextrin, the debranching dextrin is made into an aqueous solution , dissolve at 60～80℃ for 3～4h, centrifuge, and dry the precipitate to obtain spirodextrin;

(4) Disperse the obtained spirodextrin in an aqueous solution of 140-160°C and completely dissolve it, cool it to 80-100°C, and add fat-soluble nutrient ethanol preheated to 80-100°C under the condition that nitrogen is passed through the whole process to isolate oxygen. solution, constant temperature stirring;

(5) Slowly cooling the mixed solution in step (4) to room temperature for 5-7 days at a cooling rate of 0.49-0.59°C/h to obtain spirodextrin/fat-soluble nutrient crystal inclusion complex.

In order to better realize the present invention, preferably, the starch described in step (1) is one of high amylose corn starch, potato starch and tapioca starch.

Preferably, the debranching enzyme in step (2) is isoamylase or pullulanase.

Preferably, for the debranched dextrin in the precipitation concentrate, 8-10 times the volume of anhydrous ethanol is added to the concentrate to precipitate all the debranched dextrins.

Preferably, the mass concentration of the debranched dextrin prepared into an aqueous solution is 0.5-1%; the drying of the precipitate is normal pressure drying, reduced pressure drying or spray drying.

Preferably, the fat-soluble nutrients described in step (4) are resveratrol, vitamin D3 or β-carrot.

Preferably, in step (4), the concentration of spirodextrin in the aqueous solution is 4-6 mg/mL; the stirring time is 30-60 min.

Preferably, in step (4), the concentration of the fat-soluble nutrients in the ethanol solution of the fat-soluble nutrients is 3 to 5 mg/mL, and the dry basis mass ratio of the spirodextrin to the fat-soluble nutrients is 10:1 to 5:1 , the constant temperature stirring time is 1 ~ 3h.

Preferably, in step (5), the slow cooling to room temperature is to place the reaction vessel in a Dewar flask filled with boiling water after the mixed solution in step (4) is completely reacted and cooled to room temperature.

A starch-based colon-targeted controlled-release crystal inclusion compound is prepared by the above-mentioned preparation method; the starch-based colon-targeted controlled-release crystal inclusion compound is composed of starch and fat-soluble nutrients, and has a pale yellow crystal structure , the shape is regular, its relative crystallinity is 90-100%, and the release rate of fat-soluble nutrients in the small intestine is controlled not to exceed 20%.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

(1) The present invention provides a method for preparing a starch-based colon-targeted controlled-release crystal inclusion compound, which solves the problem that the traditional spirodextrin/fat-soluble nutrient inclusion compound can only transport active ingredients to the small intestine for absorption. Spirodextrin/fat-soluble nutrient crystal inclusion complex prepared by co-crystallization method can improve the stability of fat-soluble nutrients, realize the colon-targeted release function of fat-soluble nutrients, and achieve the purpose of preventing and treating colon diseases. Come to the gospel.

(2) The present invention adopts a co-crystallization method for refining solid chemicals to prepare spirodextrin/fat-soluble nutrient crystal inclusion complex. This method is mostly used in the chemical industry, and amylose and hydrophobic starch have not yet been used in the food industry. Sexual guest molecules are used. During the stirring process before the co-crystallization, the fat-soluble nutrient molecules have entered the hydrophobic cavity of the spirodextrin through the hydrophobic interaction to obtain the spirodextrin/fat-soluble nutrient inclusion complex. The molecules of the compound are highly ordered and form a perfect crystal form with a crystallinity of nearly 100%. This slow cooling and crystallization process is the key to whether the spirodextrin/fat-soluble nutrient crystal inclusion complex can achieve colon-targeted release.

(3) The present invention has the characteristics of green environmental protection and simple process, and uses spirodextrin and fat-soluble nutrients as raw materials to prepare slow and controlled-release crystal inclusion complexes, and improves its targeting, solubility and slow-release performance, which is functional activity The targeted release of substances provides favorable conditions.

(4) The present invention uses natural polysaccharide macromolecules as raw materials, is cheap and easy to obtain, has good biocompatibility, and has mild preparation process conditions, which greatly broadens the application field of starch.

Description of drawings

FIG. 1 is an X-ray diffraction (XRD) pattern of the spirodextrin/resveratrol crystal inclusion complex in Example 1 of the present invention.

2 is a scanning electron microscope (SEM) image of the spirodextrin/resveratrol crystal inclusion complex in Example 1 of the present invention.

3 is a graph showing the change of glucose content in the spirodextrin/resveratrol crystal inclusion complex in the simulated digestion process of the gastrointestinal tract in Example 1 of the present invention.

Fig. 4 is a graph showing the release rate of resveratrol in the process of simulated digestion in the gastrointestinal tract of the spirodextrin/resveratrol crystal inclusion complex in Example 1 of the present invention.

Detailed ways

For better understanding of the present invention, the present invention will be further described below with reference to the accompanying drawings and embodiments. The present invention has many successful embodiments, and five specific embodiments are listed below, but the scope of protection of the present invention is not limited to the scope of the description of the embodiments.

Preparation of artificial simulated gastrointestinal tract solution:

Artificial gastric juice: use 0.1mol/L HCl solution to prepare gastric juice containing 2g/L NaCl and 3.2g/L pepsin, pH 1.2±0.02.

Artificial small intestinal fluid: The artificial small intestinal fluid consists of 187.5 mg/2.5 mL of pancreatic enzyme solution, 3.5 mg/2.5 mL of bile salt solution, and 1.5 mL of saline solution containing 10 mM CaCl ₂ and 150 mM NaCl.

Gastrointestinal tract simulation: add 1 g of spirodextrin/fat-soluble nutrient crystal inclusion complex sample to a stoppered conical flask, and add 20 mL of simulated gastric juice prepared as above and adjusted to pH 1.2 ± 0.2 at a constant flow rate. , placed in a magnetic stirrer water bath at 37°C, stirred at a constant speed of 100rpm, and used 0.1 HCl to control the pH of the mixture to 1.2±0.2, 2h, followed by 2M NaOH to adjust the pH to 7.0±0.2, and then add 7mL of bile Salt extract, 3mL salt solution and 5mL pancreatin solution were reacted for 2h under the same conditions. In the gap during the digestion process, the sample was taken out at a predetermined time to inactivate the enzyme activity for the determination of glucose content and the analysis of the release of fat-soluble nutrients.

Example 1

A preparation method of a starch-based colon-targeted controlled-release crystal inclusion compound, comprising the following steps:

(1) The high amylose corn starch was made into 5% starch milk, placed in an airtight container and gelatinized under stirring at 150°C for 80min;

(2) Cool the gelatinized liquid obtained in step (1) to 50°C, add 7.5U/g of isoamylase (200 000U/g, Hubei Hongyunlong Biotechnology Co., Ltd.), stir and react for 12h, and inactivate the enzyme at 100°C for 20min , and cooled to obtain a debranching dextrin solution.

(3) The debranched dextrin solution in step (2) is placed in a rotary evaporator for concentration, and 9 times the volume of anhydrous ethanol is added to the concentrated solution to precipitate all the debranched dextrins in the concentrated solution. After drying, the obtained debranching dextrin was prepared into an aqueous solution with a mass concentration of 1%, dissolved at 60° C. for 4 hours, and the precipitate was centrifuged and dried at atmospheric pressure to obtain spirodextrin;

(4) Take the spirodextrin obtained in step (3) and prepare 80 mL of an aqueous solution with a concentration of 5 mg/mL, stir at 160°C for 30 minutes to completely dissolve it, cool to 90°C, and then add 10 mL while stirring at 90°C in advance Preheat the resveratrol-ethanol solution with a concentration of 4 mg/mL for 10 minutes, exhaust the air by passing nitrogen gas from below the liquid surface for 10 minutes, and stir the reaction at a constant temperature for 1 hour;

(5) After the mixed solution obtained in step (4) is completely reacted, it is placed in a Dewar flask full of boiling water, and the cooling rate is strictly controlled to be 0.58-0.59 °C/h, and the mixed solution is slowly cooled to room temperature for 5 days to crystallize, to obtain a perfect Crystal form of spirodextrin/resveratrol crystal inclusion complex.

The crystallinity of the spirodextrin/resveratrol crystal inclusion complex sample was analyzed by X-ray diffraction (Fig. 1), and the spirodextrin/resveratrol in Example 1 was analyzed by scanning electron microscopy (SEM). The morphology of the alcohol crystal inclusion complex was determined (Fig. 2). It can be seen from Figure 1 and Figure 2 that the obtained spirodextrin/resveratrol crystal inclusion complex presents a regular flaky crystal morphology, and the crystallinity is as high as 93.37%, which is close to 100%, which indicates that the spirodextrin and resveratrol are closely related to each other. Resveratrol does form a perfect crystalline structure. During the stirring process before the co-crystallization, the fat-soluble nutrient molecules have entered the hydrophobic cavity of the spirodextrin through the hydrophobic interaction to obtain the spirodextrin/fat-soluble nutrient inclusion complex. The molecules of the compound are highly ordered and form a perfect crystal form with a crystallinity of nearly 100%. The slow cooling and crystallization process is the key to whether the spirodextrin/fat-soluble nutrient crystal inclusion complex can achieve colon-targeted release.

According to literature reports (Pingping Wang, ZhigangLuo, and XichunPeng.Encapsulation ofVitamin E and Soy Isoflavone Using Spiral Dextrin:Comparative StructuralCharacterization,Release Kinetics,and Antioxidant Capacity during SimulatedGastrointestinal Tract.Journal of Agricultural and Food Chemistry,2018,66,10598-10607) , the spirodextrin/fat-soluble nutrient inclusion complex prepared by the traditional method is a V-type semi-crystalline random powder structure, and its crystallinity is not more than 40%, and research shows that this kind of V-type structure spirodextrin/ The structure of fat-soluble nutrient inclusion complexes is destroyed by pancreatic enzymes in the small intestinal juice during the digestion process. After digestion in the small intestine, the release of fat-soluble nutrients reaches almost 100%.

The spirodextrin/resveratrol crystal inclusion complex obtained in Example 1 was subjected to simulated gastrointestinal digestion, the results are shown in Figure 3 and Figure 4, the spirodextrin/resveratrol crystal inclusion complex sample was digested in the small intestine After the end, the glucose content was 38.93%, and the release of resveratrol was 15.76%. This result shows that the spirodextrin/resveratrol crystal inclusion complex can resist digestion in the stomach and small intestine, and can deliver 84.24% of resveratrol to the colon at a specific point, realizing the effect of colon-targeted controlled release carrier. Compared with the traditional spirodextrin/fat-soluble nutrient inclusion complex, it delivers almost 100% of fat-soluble nutrients in the small intestine. Although the absorption and utilization of fat-soluble nutrients in the small intestine is achieved, resveratrol is an effective preventive and Nutrients for the treatment of colitis and colon cancer, the spirodextrin/resveratrol crystal inclusion complex prepared in this example can transport most of the resveratrol to the colon, so that it can more effectively exert its nutritional and The properties of the drug bring good news to patients with colon diseases and achieve the primary purpose of the present invention, and the prior art has not been able to achieve similar effects.

The crystallinity of the samples of the following examples are analyzed and the scanning electron microscope images are basically consistent with Example 1; The graph of the release rate of resveratrol during the simulated digestion process is similar to that of Fig. 3 and Fig. 4, and is not provided one by one. The specific glucose content and the test results of the release amount of resveratrol are shown in the description of the examples.

Example 2

A preparation method of a starch-based colon-targeted controlled-release crystal inclusion compound, comprising the following steps:

(1) The tapioca starch is made into 10% starch milk, placed in an airtight container and gelatinized by stirring at 100° C. for 70min;

(2) Cool the gelatinized liquid obtained in step (1) to 45°C, add pullulanase 25U/g (OPTIMAX L-1000, Genencor Bioengineering Co., Ltd.), stir for 11h, and inactivate the enzyme at 100°C for 20min , and cooled to obtain a debranching dextrin solution.

(3) The debranched dextrin solution in step (2) is placed in a rotary evaporator for concentration, and 8 times the volume of anhydrous ethanol is added to the concentrated solution to precipitate all the debranched dextrins in the concentrated solution. After drying, the dextrin was prepared into a solution with a mass concentration of 0.5%, dissolved at 70 ° C for 3.5 hours, and the precipitate was centrifuged and spray-dried to obtain the spiral dextrin;

(4) Take the spirodextrin obtained in step (3) and prepare 100 mL of an aqueous solution with a concentration of 4 mg/mL, stir at 150° C. for 45 min to completely dissolve it, cool to 85° C., and then add 17.5 mL while stirring at 85° C. The resveratrol-ethanol solution with a concentration of 3 mg/mL was preheated in a water bath for 15 minutes, and the air was exhausted by passing nitrogen gas from below the liquid surface for 10 minutes, and the reaction was stirred at a constant temperature for 2 hours;

(5) After the mixed solution in step (4) is completely reacted, it is placed in a Dewar flask full of boiling water, and the cooling rate is strictly controlled to be 0.55-0.56 °C/h, and it is slowly cooled to room temperature for 6 days to crystallize to obtain a perfect crystal. Spirodextrin/resveratrol crystal inclusion complex.

The spirodextrin/resveratrol crystal inclusion compound sample obtained in this Example 2 had a glucose content of 36.34% and a resveratrol release amount of 12.84% after digestion in the small intestine. This result shows that the spirodextrin/resveratrol crystal inclusion complex can resist digestion in the stomach and small intestine, and can deliver 87.16% of resveratrol to the colon at a specific point, realizing the effect of colon-targeted controlled release carrier.

Example 3

A preparation method of a starch-based colon-targeted controlled-release crystal inclusion compound, comprising the following steps:

(1) The potato starch was made into 8% starch milk, placed in an airtight container, and gelatinized under stirring at 100°C for 60min;

(2) Cool the gelatinized liquid obtained in step (1) to 60°C, add 25U/g of isoamylase (200 000U/g, Hubei Hongyunlong Biotechnology Co., Ltd.), stir and react for 10h, inactivate the enzyme at 100°C for 20min, Debranched dextrin solution was obtained by cooling.

(3) The debranched dextrin solution in step (2) is placed in a rotary evaporator for concentration, and 10 times the volume of anhydrous ethanol is added to the concentrated solution to precipitate all the debranched dextrins in the concentrated solution. The obtained debranching dextrin was made into a 0.75% solution and dissolved at 80° C. for 3 hours, and the precipitate was centrifuged to obtain the spirodextrin by drying under reduced pressure;

(4) Take the spirodextrin obtained in step (3) and prepare 70 mL of an aqueous solution with a concentration of 6 mg/mL, stir at 140° C. for 60 min to completely dissolve it, cool to 80° C., and then add 12 mL while stirring at 80° C. in advance A vitamin D3-ethanol solution with a concentration of 5 mg/mL was preheated in a water bath for 12 minutes, and the air was exhausted by introducing nitrogen gas from below the liquid surface for 10 minutes, and the reaction was stirred at a constant temperature for 3 hours;

(5) After the mixed solution in step (4) is completely reacted, it is placed in a Dewar flask full of boiling water, and the cooling rate is strictly controlled to be 0.49-0.50 °C/h, and it is slowly cooled to room temperature for 7 days to crystallize, and a perfect crystal is obtained. type of spirodextrin/vitamin D3 crystal inclusion complex.

The spirodextrin/vitamin D3 crystal inclusion compound sample obtained in this Example 3 had a glucose content of 31.15% and a release amount of vitamin D3 of 17.34% after digestion in the small intestine. The results show that the spirodextrin/vitamin D3 crystal inclusion complex can resist digestion in the stomach and small intestine, and can deliver 82.66% of vitamin D3 to the colon at a specific point, realizing the effect of colon-targeted controlled release carrier.

Example 4

A preparation method of a starch-based colon-targeted controlled-release crystal inclusion compound, comprising the following steps:

(1) The high amylose corn starch was made into 7% starch milk, placed in an airtight container, and gelatinized at 135° C. for 75 minutes with stirring;

(2) Cool the gelatinized liquid obtained in step (1) to 50°C, add pullulanase 20U/g (OPTIMAX L-1000, Genencor Bioengineering Co., Ltd.), stir for 11h, and inactivate the enzyme at 100°C for 20min , and cooled to obtain a debranching dextrin solution.

(3) The debranched dextrin solution in step (2) is placed in a rotary evaporator for concentration, and 9.5 times the volume of anhydrous ethanol is added to the concentrated solution to precipitate all the debranched dextrins in the concentrated solution. The obtained debranching dextrin was made into a 1% solution and dissolved at 60° C. for 4 hours, and the precipitate was centrifuged and dried under reduced pressure to obtain the spirodextrin;

(4) Take the spirodextrin obtained in step (3) and prepare 90 mL of an aqueous solution with a concentration of 4.5 mg/mL, stir at 155 ° C for 35 min to completely dissolve it, cool to 100 ° C, and then add 11 mL while stirring at 100 ° C in advance. The β-carotene-ethanol solution with a concentration of 4.5 mg/mL was preheated in a water bath for 14 minutes, and the air was exhausted by passing nitrogen gas from below the liquid surface for 10 minutes, and the reaction was stirred at a constant temperature for 1.5 hours;

(5) After the mixed solution in step (4) is completely reacted, it is placed in a Dewar flask full of boiling water, and the cooling rate is strictly controlled to be 0.52-0.53 °C/h, and it is slowly cooled to room temperature for 6 days to crystallize to obtain a perfect crystal. type of spirodextrin/β-carotene crystal inclusion complex.

After digestion in the small intestine of the spirodextrin/β-carotene crystal inclusion compound sample obtained in Example 4, the glucose content was 39.39%, and the release amount of β-carotene was 14.65%. The results show that the spirodextrin/β-carotene crystal inclusion complex can resist digestion in the stomach and small intestine, and can deliver 85.35% of β-carotene to the colon at a specific point, realizing the effect of colon-targeted controlled release carrier.

Example 5

A preparation method of a starch-based colon-targeted controlled-release crystal inclusion compound, comprising the following steps:

(1) The potato and corn starch was made into 9% starch milk, placed in an airtight container, and gelatinized at 110° C. for 60 min under stirring;

(2) Cool the gelatinized liquid obtained in step (1) to 50°C, add isoamylase 12.5U/g (200 000U/g, Hubei Hongyunlong Biotechnology Co., Ltd.), stir for 12h, and inactivate the enzyme at 100°C for 20min , and cooled to obtain a debranching dextrin solution.

(3) The debranched dextrin solution in step (2) is placed in a rotary evaporator for concentration, and 8.5 times the volume of anhydrous ethanol is added to the concentrated solution to precipitate all the debranched dextrins in the concentrated solution. The obtained debranching dextrin was made into a 1% solution and dissolved at 70°C for 3 hours, and the precipitate was centrifuged to obtain the spirodextrin by drying under reduced pressure;

(4) Take the spirodextrin obtained in step (3) and prepare 80 mL of an aqueous solution with a concentration of 6 mg/mL, stir at 150 ° C for 50 min to make it completely dissolved, cool to 80 ° C, and then add 19.2 mL while stirring at 80 ° C in advance. Preheat a β-carotene-ethanol solution with a concentration of 5 mg/mL at ℃ for 14 minutes, exhaust the air by passing nitrogen gas from below the liquid surface for 10 minutes, and stir at a constant temperature for 1.5 hours;

(5) After the mixed solution in step (4) is completely reacted, it is placed in a Dewar flask full of boiling water, and in a Dewar flask of boiling water, the cooling rate is strictly controlled to be 0.55～0.56°C/h, and it is slowly cooled to room temperature for crystallization After 5 days, a spirodextrin/β-carotene crystal inclusion complex with perfect crystal form was obtained.

After digestion in the small intestine of the spirodextrin/β-carotene crystal inclusion compound sample obtained in Example 5, the glucose content was 35.72%, and the release amount of β-carotene was 15.14%. The results show that the spirodextrin/β-carotene crystal inclusion complex can resist digestion in the stomach and small intestine, and can deliver 84.86% of β-carotene to the colon at a specific point, realizing the effect of colon-targeted controlled release carrier.

The above-mentioned embodiments are used to explain the present invention, rather than limit the present invention. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principle of the present invention should be equivalent replacement methods. All are included in the protection scope of the present invention.

Claims (10)

1. a preparation method of starch-based colon targeted controlled-release crystal inclusion compound, is characterized in that comprising the steps: (1) The starch raw material is made into starch milk with a mass percentage concentration of 5% to 10%, and placed in a closed container for gelatinization under stirring at 100 to 150 ° C for 60 to 80 minutes; (2) Cool the gelatinized liquid obtained in step (1), add debranching enzyme, and the dosage is 7.5-25 U per gram of dry starch, and stir and react at 45-60° C. for 10-12 hours; dextrin debranching Complete, inactivated enzyme, cooled to obtain debranched dextrin solution; (3) placing the debranching dextrin solution in step (2) in a rotary evaporator for concentration, and precipitating the debranching dextrin in the concentrated solution; after centrifugal drying the debranching dextrin, the debranching dextrin is made into an aqueous solution , dissolve at 60～80℃ for 3～4h, centrifuge, and dry the precipitate to obtain spirodextrin; (4) Disperse the obtained spirodextrin in an aqueous solution of 140-160°C and completely dissolve it, cool it to 80-100°C, and add fat-soluble nutrient ethanol preheated to 80-100°C under the condition that nitrogen is passed through the whole process to isolate oxygen. solution, constant temperature stirring; (5) Slowly cooling the mixed solution in step (4) to room temperature for 5-7 days at a cooling rate of 0.49-0.59°C/h to obtain spirodextrin/fat-soluble nutrient crystal inclusion complex. 2. the preparation method of starch-based colon-targeted controlled-release crystal inclusion compound according to claim 1, is characterized in that: the starch described in step (1) is a kind of in high amylose corn starch, potato starch and tapioca starch . 3 . The preparation method of the starch-based colon-targeted controlled-release crystal inclusion complex according to claim 1 , wherein the debranching enzyme described in step (2) is isoamylase or pullulanase. 4 . 4. The preparation method of the starch-based colon-targeted controlled-release crystal inclusion compound according to claim 1, wherein the debranched dextrin in the described precipitation concentrate is added 8 to 10 times the volume of the concentrate of absolute ethanol to completely precipitate the debranching dextrins. 5. The preparation method of the starch-based colon-targeted controlled-release crystal inclusion complex according to claim 1, characterized in that: the mass concentration of the debranched dextrin made into an aqueous solution is 0.5-1%; the precipitation Drying is atmospheric drying, vacuum drying or spray drying. 6. the preparation method of starch-based colon-targeted controlled-release crystal inclusion compound according to claim 1, is characterized in that: the fat-soluble nutrient described in step (4) is resveratrol, vitamin D3 or beta-carrot . 7. The preparation method of the starch-based colon-targeted controlled-release crystal inclusion complex according to claim 1, characterized in that: in step (4), the concentration of spirodextrin in the aqueous solution is 4～6 mg/mL; stirring The time is 30 to 60 minutes. 8. The preparation method of the starch-based colon-targeted controlled-release crystal inclusion compound according to claim 1, characterized in that: in step (4), the concentration of the fat-soluble nutrients in the ethanol solution of the fat-soluble nutrients is 3～ 5mg/mL, the dry mass ratio of spirodextrin and fat-soluble nutrients is 10:1～5:1, and the constant temperature stirring time is 1～3h. 9. the preparation method of starch-based colon-targeted controlled-release crystal inclusion compound according to claim 1, is characterized in that: in step (5), described slow cooling to room temperature is to react mixed solution in step (4) After completion, the reaction vessel was placed in a Dewar filled with boiling water and cooled to room temperature. 10. A starch-based colon-targeted controlled-release crystal inclusion compound, characterized in that, it is prepared by the preparation method described in any one of claims 1-9; the starch-based colon-targeted controlled-release crystal The inclusion compound is composed of starch and fat-soluble nutrients, and has a pale yellow crystal structure with a regular shape. Its relative crystallinity is 90-100%, and the release rate of the fat-soluble nutrients after being digested in the small intestine is controlled not to exceed 20%.

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