Cattle pancreas extract as well as preparation method and application thereof

Abstract

The invention relates to the technical field of biological pharmacy, in particular to a cattle pancreas extract as well as a preparation method and application thereof. According to the preparation method of the bovine pancreas extract, bovine pancreas is used as a raw material, and the bovine pancreas extract is obtained through chopping, liquid nitrogen quick-freezing, liquid nitrogen quick-freezing, cell membrane breaking, protein removal, purification and freeze drying. The invention aims at improving the problem of hyperglycemia of a human body by a root method and provides the bovine pancreas extract capable of promoting division and increase of islet cells of the human body, secreting insulin and reducing blood sugar, and the implementation of the bovine pancreas extract opens a new thought and direction for innovative application of bovine pancreas. A product which is safe, effective, free of toxic and side effects and capable of treating the hyperglycemia from the source is provided for people suffering from the hyperglycemia, economic and psychological burdens caused by medical treatment are reduced, and social significance is great.

Description

Technical Field

[0001] The invention relates to the technical field of biopharmaceuticals, and in particular to a bovine pancreas extract and a preparation method and application thereof. Background Art

[0002] Bovine pancreas contains a variety of active ingredients, such as insulin-like growth factor, which can regulate the body's immune response and enhance the body's immunity. The biologically active substances contained in it, such as growth hormone-releasing peptide, have the effect of stimulating cell division and proliferation, thereby promoting the growth and development of tissues and organs of the body. The substances contained in it, such as insulin-like growth factor, can regulate blood sugar concentration by affecting the secretion of insulin by pancreatic β cells, which helps to control blood sugar levels to a certain extent. RNA extracted from bovine pancreas participates in regulating the cell cycle process through interaction with specific protein factors, affecting cell growth and division, especially promoting the increase of pancreatic cell division. However, the bovine pancreatic RNA extracted by the traditional phenol-chloroform method contains organic reagents, has low purity, poor biological activity, and the large-scale use of organic reagents is not environmentally friendly. Summary of the invention

[0003] In view of this, the technical problem to be solved by the present invention is to provide a safe, effective, high-purity, high-activity and non-toxic bovine pancreas extract and a preparation method and application thereof.

[0004] The present invention provides a method for preparing a bovine pancreas extract, comprising the following steps:

[0005] Step 1, washing, freezing, thawing and homogenizing the bovine pancreas to obtain a homogenate;

[0006] Step 2, taking the homogenate described in step 1 and subjecting it to cell membrane hydrolysis, protein hydrolysis, and RNA hydrolysis in sequence to obtain a hydrolyzate;

[0007] Step 3: Centrifuge the hydrolyzate obtained in step 2, collect the supernatant, perform ultrafiltration, collect the permeate, and freeze-dry the permeate to obtain a bovine pancreatic extract.

[0008] In some embodiments, in step 1,

[0009] The freeze-thaw comprises freezing and thawing, wherein the freezing comprises freezing the bovine pancreas with liquid nitrogen for 30 to 60 minutes, and the thawing temperature is 25° C.±5° C.;

[0010] The homogenate comprises mixing the bovine pancreas with water at a mass ratio of 1:(5-10), and then homogenizing with a colloid mill to obtain the homogenate.

[0011] In some specific embodiments, the freezing time is 60 minutes, and the mass ratio of the bovine pancreas to water is 1:10.

[0012] In some embodiments, in step 2,

[0013] The cell membrane hydrolysis comprises mixing the homogenate with phospholipase at a mass ratio of 100:(0.1-0.4) and reacting for 3-6 hours. The temperature of the cell membrane hydrolysis is 45°C-60°C and the pH value of the cell membrane hydrolysis is 7.5-9.0.

[0014] In some embodiments, in step 2,

[0015] The protein hydrolyzing enzyme comprises at least one of alkaline protease, neutral protease, bromelain and papain;

[0016] The protein hydrolysis comprises mixing the cell membrane hydrolyzed solution with the protein hydrolyzing enzyme at a mass ratio of 100:(0.1-0.4) and reacting for 3-6 hours. The protein hydrolysis temperature is 45°C-60°C and the protein hydrolysis pH is 7.0-9.0.

[0017] In some embodiments, in step 2,

[0018] The ribonucleic acid hydrolysis comprises mixing the protein hydrolyzed solution with ribonuclease at a mass ratio of 100:(0.1-0.4) and reacting for 4-10 hours. The temperature of the ribonucleic acid hydrolysis is 45°C-60°C, and the pH value of the ribonucleic acid hydrolysis is 6.5-8.0.

[0019] In some specific embodiments, in step 2,

[0020] The cell membrane hydrolysis comprises mixing the homogenate with phospholipase at a mass ratio of 100:(0.3-0.4) and reacting for 3-4 hours, the temperature of the cell membrane hydrolysis is 55° C., and the pH value of the cell membrane hydrolysis is 8.5;

[0021] The protein hydrolysis enzyme is alkaline protease, and the protein hydrolysis includes mixing the cell membrane hydrolyzed solution with alkaline protease at a mass ratio of 100:(0.3-0.4) and reacting for 3-4 hours. The protein hydrolysis temperature is 55°C and the protein hydrolysis pH is 8.5.

[0022] The ribonucleic acid hydrolysis comprises mixing the protein hydrolyzed solution with ribonuclease at a mass ratio of 100:(0.3-0.4) and reacting for 4-6 hours. The temperature of the ribonucleic acid hydrolysis is 55° C. and the pH value of the ribonucleic acid hydrolysis is 7.5.

[0023] In some more specific embodiments, in step 2,

[0024] The mass ratio of the homogenate to the phospholipase is 100:0.3 and the mixture is reacted for 3 hours;

[0025] The mass ratio of the cell membrane hydrolysis solution to the protein hydrolysis enzyme is 100:0.3, and the mixture is reacted for 4 hours.

[0026] The protein hydrolyzed solution and ribonuclease were mixed in a mass ratio of 100:0.4 and reacted for 6 hours.

[0027] In some embodiments, step 2 further comprises filtering the protein hydrolyzed solution through an ultrafiltration membrane of 100-200K Daltons, and then subjecting the obtained filtrate to RNA hydrolysis.

[0028] In some specific embodiments, the protein hydrolyzed solution is filtered through a 100K Dalton ultrafiltration membrane.

[0029] In some embodiments, in step 3, the pore size of the membrane used for ultrafiltration is 50~200K Daltons.

[0030] In some specific embodiments, the membrane pore size used in the ultrafiltration is 100K Dalton.

[0031] The invention provides a bovine pancreas extract prepared by the preparation method.

[0032] The present invention provides the use of the bovine pancreas extract in any of the following items:

[0033] ( ), preparing products that promote the separation and increase of pancreatic islet cells;

[0034] ( ), preparing products that promote insulin secretion;

[0035] ( ), preparing products that lower blood sugar.

[0036] The invention provides a product comprising the bovine pancreas extract.

[0037] Compared with the prior art, the beneficial effects of the present invention include:

[0038] (1) The present invention uses bovine pancreas as raw material, cuts it into pieces and freezes it in liquid nitrogen, grinds it into minced meat after thawing, and then destroys its cell membrane with phospholipase, which can release its cell contents to a greater extent, thereby improving the utilization rate of the raw materials;

[0039] (2) The present invention uses proteolytic enzymes to hydrolyze the macromolecular proteins contained in the bovine pancreas into small molecular peptides, and then uses ultrafiltration to separate the small molecular peptides to achieve the purpose of removing proteins and purifying RNA. Compared with the traditional phenol-chloroform method, this method is more environmentally friendly and safe;

[0040] (3) The present invention provides an innovative research direction for promoting pancreatic islet cell division and secretion of insulin, thereby lowering blood sugar. Compared with traditional drug treatments, the present invention has the characteristics of mild action and obvious efficacy. In addition, the invention product has a high degree of application and industrialization, and is expected to have considerable economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The growth effect diagram of mouse islet cells after culturing for 24 hours in Example 1 is shown;

[0042] Figure 2 The total amount of MTT reduction product after culturing mouse pancreatic islet cells for 24 hours in Example 1 is shown;

[0043] Figure 3 Graph showing changes in blood glucose levels in mice in Effect Example 2. DETAILED DESCRIPTION

[0044] The present invention provides bovine pancreas extract and its preparation method and application. 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 substitutions and modifications are obvious to those skilled in the art, and they are all considered to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application 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.

[0045] The present invention mainly provides a bovine pancreas extract and a preparation method thereof, and the preparation process is as follows:

[0046] S1: Wash and chop fresh bovine pancreas, freeze it in liquid nitrogen, thaw it, add water and homogenize it to obtain homogenate A;

[0047] S2: hydrolyzing the cell membrane of the homogenate A to obtain a hydrolyzate B;

[0048] S3: hydrolyzing the protein in the hydrolyzate B to obtain hydrolyzate C;

[0049] S4: ultrafiltering the hydrolyzate C, adding water for elution, and collecting the concentrated solution D;

[0050] S5: hydrolyzing the concentrated solution D with ribonucleic acid, and collecting the hydrolyzate E;

[0051] S6: centrifuging the hydrolyzate E, collecting the supernatant for ultrafiltration, collecting the permeate, and vacuum freeze-drying to obtain a bovine pancreatic extract.

[0052] Preferably, the bovine pancreas in the above step S1 is a fresh pancreas purchased from a slaughterhouse, the liquid nitrogen quick freezing time is 30 to 60 minutes, the melting temperature is 25°C ± 5°C, and the amount of water added is 5 to 10 times the weight of the bovine pancreas.

[0053] Preferably, the cell membrane hydrolysis in the above step S2 uses phospholipase, the addition amount of which is 0.1% to 0.4% by weight of the homogenate A, the hydrolysis temperature is 45° C. to 60° C., the hydrolysis pH is 7.5 to 9.0, and the hydrolysis time is 3 to 6 hours.

[0054] Preferably, in the above step S3, alkaline protease, neutral protease, bromelain or papain are used for protein hydrolysis.

[0055] Preferably, the pore size of the ultrafiltration membrane in the above step S4 is 100-200K Daltons, and the number of times of adding water for elution is 3-5 times.

[0056] Preferably, in the above step S5, ribonucleic acid hydrolysis adopts ribonuclease, and its addition amount is 0.1%~0.4% of the weight of the concentrated solution D, the hydrolysis temperature is 45℃~60℃, the hydrolysis pH value is 6.5~8.0, and the hydrolysis time is 4~10 hours.

[0057] Preferably, the pore size of the ultrafiltration membrane in step S6 is 50-200K Daltons.

[0058] The test materials used in the present invention are all common commercial products and can be purchased on the market. Among them:

[0059] Phospholipase was purchased from Shanghai Yingxin Laboratory Equipment Co., Ltd., catalog number: TXL8867-25g;

[0060] Alkaline protease was purchased from Shanghai Yingxin Laboratory Equipment Co., Ltd., catalog number: ;

[0061] Neutral protease was purchased from Shanghai Yingxin Laboratory Equipment Co., Ltd., catalog number: ;

[0062] Bromelain was purchased from Shanghai Yingxin Laboratory Equipment Co., Ltd., catalog number: ;

[0063] Papain was purchased from Shanghai Yingxin Laboratory Equipment Co., Ltd., catalog number: ;

[0064] Ribonuclease was purchased from Shanghai Yingxin Laboratory Equipment Co., Ltd., catalog number: ;

[0065] The present invention will be further described below in conjunction with the embodiments.

[0066] Example 1 Experiment on the effect of liquid nitrogen quick freezing time on the damage rate of bovine pancreatic cells

[0067] Wash fresh bovine pancreas, drain, cut into small pieces, and divide into five groups. One group is not frozen with liquid nitrogen, and the other four groups are placed in liquid nitrogen for 30, 40, 50, and 60 minutes, respectively. After the freezing, take out and thaw in 25℃±5℃ environment. When completely thawed, add 10 times the weight of bovine pancreas in water and put it into the colloid mill for homogenization. Take an appropriate amount of homogenate and drop it on the blood cell counting plate. Observe and record the number of intact cells in the counting grid under a high-power microscope. Take samples and observe and count twice in parallel for each group, and calculate the cell damage rate A. The results are shown in Table 1:

[0068] Table 1 Statistical table of cell damage rate A of bovine pancreatic homogenate after quick freezing in liquid nitrogen

[0069]

[0070] Ps. Cell damage rate A = (1-average number of intact cells in each group ÷ number of intact cells at 0 minutes) × 100%

[0071] From the results in Table 1, it can be seen that the longer the bovine pancreas is frozen in liquid nitrogen, the higher the cell damage rate is, which means that the cell contents are released more thoroughly and the raw material utilization rate is higher.

[0072] Example 2 Orthogonal experiment of phospholipase hydrolysis conditions

[0073] In order to further destroy the integrity of bovine pancreatic cells and improve the utilization rate of raw materials, the present invention studied the hydrolysis of cell membrane of bovine pancreatic cells by phospholipase. The influencing factors and level selection of orthogonal experiment are shown in Table 2:

[0074] Table 2 Factors and levels of orthogonal experiment of phospholipase enzymatic hydrolysis process

[0075]

[0076] The influencing factors and levels are determined, and the present invention adopts L 16 (4 4 ) The orthogonal array was designed and tested as shown in Table 3 below.

[0077] Table 3 Orthogonal experimental design

[0078]

[0079] Wash fresh bovine pancreas, drain, cut into small pieces, put into liquid nitrogen for 50 minutes, take out and thaw in 25℃±5℃ environment, add 10 times the weight of bovine pancreas water after complete thawing, put into colloid mill for homogenization. Take a sample of homogenate and drop it on the blood cell counting plate, observe and record the number of intact cells in the counting grid under a high-power microscope, take samples twice in parallel and observe and record. The remaining homogenate was tested according to Table 3 above.

[0080] Take the enzymatic hydrolysis solution of each group and drop it onto the blood cell counting plate. Observe and record the number of intact cells in the counting grid under a high-power microscope. Take samples from each group and observe and count them twice in parallel. Calculate the cell damage rate B (the enzymatic hydrolysis effect is proportional to the cell damage rate B). The results are shown in Table 4:

[0081] Cell damage rate B = (1-average number of intact cells in each group ÷ number of intact cells in homogenate) × 100%

[0082] Table 4 Statistical table of cell damage rate B results

[0083]

[0084] From the results in Table 4, it can be concluded that the damage rate of bovine pancreatic cells in the enzymatic hydrolyzate of experimental group 15 is the highest, and the enzymatic hydrolysis effect is the best, followed by experimental group 11. Considering the comprehensive cost, time and other aspects, the subsequent experiments of the present invention adopt the conditions of experimental group 11.

[0085] Example 3 Screening of protein hydrolases

[0086] Different proteolytic enzymes have different action sites on the same protein, and their binding to the substrate is also specific, and the degree of hydrolysis is also different. The higher the degree of hydrolysis, the more conducive it is to the subsequent protein removal operation. The present invention screened four proteolytic enzymes, and the hydrolysis conditions of the four enzymes are shown in Table 5:

[0087] Table 5 Hydrolysis conditions of different proteases

[0088]

[0089] Wash fresh bovine pancreas, drain the water, weigh and record, cut into small pieces, put into liquid nitrogen for 50 minutes, take out and thaw in 25℃±5℃ environment, add 10 times the weight of bovine pancreas water after complete thawing, and put into colloid mill for homogenization. Collect the homogenate and adjust the pH value to 8.5, weigh it, add 0.3% of its weight of phospholipase, stir and hydrolyze at 55℃ for 3 hours, and divide the phospholipase hydrolyzate into four groups, and carry out protein hydrolase screening experiment according to the conditions described in Table 5. After the end, pass through 100K Dalton ultrafiltration membrane respectively, collect the permeate, and add water to make up to the same volume. Take the permeate after each group is made up to the total nitrogen content per ml according to the Kjeldahl nitrogen determination method. The results are shown in Table 6:

[0090]

[0091] Where: F is the titrant correction value: 1.0035; N is the dilution multiple of the sample; the titrant used is 0.1 mol / L hydrochloric acid titrant

[0092] Table 6 Results of total nitrogen content per unit volume of protein hydrolyzed permeate

[0093]

[0094] From the total nitrogen detection results in Table 6, it can be concluded that when the permeate was fixed to the same volume, the total nitrogen content of the alkaline protease experimental group was 24.95 mg / ml, which was significantly higher than the results of the other three groups, indicating that it has the strongest ability to hydrolyze bovine pancreatic protein, which is more in line with the purpose of removing protein by enzymatic ultrafiltration of the present invention.

[0095] Example 4 Orthogonal experiment of ribonuclease hydrolysis conditions

[0096] Ribonuclease can hydrolyze large ribonucleic acid (RNA) into small molecular fragments, which makes it easier to separate it from DNA by ultrafiltration. Small RNA fragments are also more easily absorbed and utilized by the body, and the degree of RNA hydrolysis directly affects the yield of the finished product. Therefore, the present invention uses an orthogonal experimental method to study the optimal hydrolysis conditions of ribonuclease. The influencing factors and level values ​​are shown in Table 7:

[0097] Table 7 Factors and levels of orthogonal experiment of ribonuclease hydrolysis

[0098]

[0099] After determining the influencing factors and levels, continue to use the L16 (44) orthogonal table for design and testing:

[0100] Table 8 Orthogonal experimental design

[0101]

[0102] Wash fresh bovine pancreas, drain water, weigh and record, cut into small pieces, put into liquid nitrogen for 50 minutes, take out and thaw in 25℃±5℃ environment after completion, add 10 times the weight of bovine pancreas water after complete thawing, put into colloid mill for homogenization. Collect the homogenate and adjust the pH value to 8.5, weigh, add 0.3% of its weight of phospholipase, stir and hydrolyze at 55℃ for 3 hours, add 0.3g / 100g of bovine pancreas weight of alkaline protease after completion, adjust the pH value of the feed liquid to 8.5, stir and hydrolyze at 55℃ for 4 hours. Take the alkaline protease hydrolyzate and pass it through a 100K Dalton ultrafiltration membrane, add water to the reflux liquid for 5 times, and collect the concentrate. Take equal amounts of the concentrate according to the design of Table 8 to perform ribonuclease hydrolysis experiments. After the end, centrifuge at 10000r / min for 30 minutes, take the supernatant and pass it through a 100K Dalton ultrafiltration membrane, collect the permeate, add water to the same volume, take a sample and dilute it 10 times with water as the test solution, and use the UV-visible spectrophotometer to zero with water at a wavelength of 260nm to detect the absorbance value of the test solution of each experimental group and record it:

[0103] Table 9 Absorbance values ​​of the test solutions in each experimental group at a wavelength of 260 nm

[0104]

[0105] RNA has the maximum absorption of light at a wavelength of 260nm, and the absorbance value is proportional to the RNA content in the solution. From Table 9, it can be seen that the average absorbance of the test solution of the 4-3 experimental group is 0.8775, which is the highest value in this experiment, followed by the 3-3 experimental group, indicating that the hydrolysis conditions of the 4-3 experimental group are optimal. The remaining permeate of the 4-3 experimental group was vacuum freeze-dried to obtain a bovine pancreatic extract sample.

[0106] Comparative Example 1: Traditional phenol-chloroform method for extracting bovine pancreatic extract

[0107] Wash fresh bovine pancreas, drain, chop, add 3 times the weight of bovine pancreas water for homogenization, collect the homogenate, weigh, add 0.3 times the weight of the homogenate phenol, 0.1 times the weight of chloroform, shake for 30 minutes, stand in a separatory funnel to separate layers, take the upper clear liquid, repeat the phenol chloroform protein removal operation twice, collect the supernatant, and measure the volume. Add 2 times the volume of 95% ethanol to the clear liquid, mix well, stand for 30 minutes, centrifuge at 4000r / min for 20 minutes, collect the precipitate and vacuum freeze-dry to obtain the bovine pancreas extract.

[0108] Effect Example 1 Experiment on the Effect of Bovine Pancreas Extract on the Growth of Mouse Islet Cells

[0109] The mouse pancreatic islet cells used in this experiment were purchased from Shanghai Fusheng Industrial Co., Ltd., model: A01X1856

[0110] Three equal portions of mouse islet cells were taken and inoculated in cell culture medium, numbered 1, 2, and 3. 5 ml of sterile saline was added to medium No. 1; 5 ml of bovine pancreatic extract A solution was added to medium No. 2 (an appropriate amount of bovine pancreatic extract from the experimental group 4-3 in Example 4 was taken and prepared into a 1 mg / ml solution with sterile saline); and 5 ml of bovine pancreatic extract B solution was added to medium No. 3 (an appropriate amount of bovine pancreatic extract from comparative example 1 was taken and prepared into a 1 mg / ml solution with sterile saline). After culturing at 37°C for 24 hours, the cell activity per unit cell fluid was detected by the MTT colorimetric method (the MTT detection kit was purchased from Shanghai Beibo Biotechnology Co., Ltd. BB-4201-250T), and the number of intact cells in the cell fluid of each group was calculated by the hemocytometer method. The results are shown in Table 10 below. The growth effect diagram of mouse islet cells after culturing for 24 hours is shown in the figure below. Figure 1 As shown in the figure, the total amount of MTT reduction product after 24 hours of mouse islet cell culture Figure 2 shown.

[0111] Table 10 Effect of mouse pancreatic islet cell culture

[0112]

[0113] The MTT original product in the above chart is formazan reduced by dehydrogenase in living mouse islet cells. The higher the content, the higher the cell activity.

[0114] Depend on Figure 1 , Figure 2 As shown in Table 10, bovine pancreas extract does promote the growth of mouse pancreatic islet cells and has high activity. The bovine pancreas extract samples of the experimental groups of Example 4 and 4-3 have better experimental effects than those of Comparative Example 1.

[0115] Effect Example 2 Experiment on the Effect of Bovine Pancreas Extract on Glucose Metabolism in Mice

[0116] 40 Kunming mice were randomly divided into 4 groups, 10 mice in each group: negative control group, each mouse was intraperitoneally injected with 2 ml of saline every day; positive control group, each mouse was intraperitoneally injected with 2 ml of saline every day, and then injected with 2 ml of 5% glucose solution 2 hours later (take an appropriate amount of glucose and prepare a 50 mg / ml solution with saline); sample group A, each mouse was intraperitoneally injected with 2 ml of bovine pancreatic extract A solution every day (take an appropriate amount of bovine pancreatic extract of experimental group 4-3 in Example 4 and prepare a 50 mg / ml solution with sterile saline); sample group B, each mouse was intraperitoneally injected with 2 ml of bovine pancreatic extract B solution every day (take an appropriate amount of bovine pancreatic extract of comparative example 1 and prepare a 50 mg / ml solution with sterile saline). On the 21st day of feeding, 2 hours after the injection of each group, each mouse in the negative control group was injected with 2 ml of saline, and the positive control group, sample group A, and sample group B were injected with 2 ml of 15% glucose solution respectively. 30 minutes after the injection, the right eye of the mouse was removed to collect blood and preserve it. 60 minutes after the injection, the left eye of the mouse was removed to collect blood, and the blood glucose levels of the two collected blood samples were tested. The blood glucose microassay kit produced by Shanghai Fusheng Industrial Co., Ltd. was used for testing blood glucose, and the test results are shown in Table 11 and Figure 3 .

[0117] Table 11 Statistics of blood glucose content test results in mice

[0118]

[0119] Depend on Figure 3 It can be seen from Table 11 that mice that have been taking bovine pancreatic extract for a reasonable period of time can balance their blood sugar levels well in a short period of time after being injected with excessive glucose. 60 minutes after the injection of excessive glucose solution, the blood sugar levels of mice in sample A group returned to normal levels, and the blood sugar levels of mice in sample B group also returned to normal levels, but the effect was not as good as that of sample A group.

[0120] From the above results, we can see that bovine pancreatic extract can promote the increase of pancreatic islet cell division, secrete insulin and lower blood sugar.

[0121] 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 method for preparing a bovine pancreas extract, characterized in that: The steps include: Step 1, washing, freezing, thawing and homogenizing the bovine pancreas to obtain a homogenate; Step 2, taking the homogenate described in step 1 and subjecting it to cell membrane hydrolysis, protein hydrolysis, and RNA hydrolysis in sequence to obtain a hydrolyzate; Step 3: Centrifuge the hydrolyzate obtained in step 2, collect the supernatant, perform ultrafiltration, collect the permeate, and freeze-dry the permeate to obtain a bovine pancreatic extract.

2. The preparation method according to claim 1, characterized in that: In the step 1, The freeze-thaw comprises freezing and thawing, wherein the freezing comprises freezing the bovine pancreas with liquid nitrogen for 30 to 60 minutes, and the thawing temperature is 25° C.±5° C.; The homogenate comprises mixing the bovine pancreas with water at a mass ratio of 1:(5-10), and then homogenizing with a colloid mill to obtain the homogenate.

3. The preparation method according to claim 1 or 2, characterized in that: In the step 2, The cell membrane hydrolysis comprises mixing the homogenate with phospholipase at a mass ratio of 100:(0.1-0.4) and reacting for 3-6 hours. The temperature of the cell membrane hydrolysis is 45°C-60°C and the pH value of the cell membrane hydrolysis is 7.5-9.

0.

4. The preparation method according to any one of claims 1 to 3, characterized in that In the step 2, The protein hydrolyzing enzyme comprises at least one of alkaline protease, neutral protease, bromelain and papain; The protein hydrolysis comprises mixing the cell membrane hydrolyzed solution with the protein hydrolyzing enzyme at a mass ratio of 100:(0.1-0.4) and reacting for 3-6 hours. The protein hydrolysis temperature is 45°C-60°C and the protein hydrolysis pH is 7.0-9.

0.

5. The preparation method according to any one of claims 1 to 4, characterized in that In the step 2, The ribonucleic acid hydrolysis comprises mixing the protein hydrolyzed solution with ribonuclease at a mass ratio of 100:(0.1-0.4) and reacting for 4-10 hours. The temperature of the ribonucleic acid hydrolysis is 45°C-60°C, and the pH value of the ribonucleic acid hydrolysis is 6.5-8.

0.

6. The preparation method according to any one of claims 1 to 5, characterized in that The step 2 further comprises filtering the protein hydrolyzed solution through an ultrafiltration membrane of 100-200K Dalton, and then hydrolyzing the filtrate with RNA.

7. The preparation method according to any one of claims 1 to 6, characterized in that In the step 3, the pore size of the membrane used for ultrafiltration is 50~200K Daltons.

8. Bovine pancreas extract obtained by the preparation method according to any one of claims 1 to 7.

9. Use of the bovine pancreas extract according to claim 8 in any of the following items; ( ), preparing products that promote the separation and increase of pancreatic islet cells; ( ), preparing products that promote insulin secretion; ( ), preparing products that lower blood sugar.

10. A product, characterized in that The invention comprises the bovine pancreas extract as claimed in claim 8.

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