Polypeptide composition for increasing bone mineral density and preparation method thereof

Abstract

The invention discloses a polypeptide composition for increasing bone mineral density and a preparation method thereof, and belongs to the technical field of food health care. When the polypeptide composition provided by the invention is continuously taken, the calcium content, phosphorus content and bone density of bones of rats with osteoporosis can be remarkably increased, absorption and metabolism of nutrient substances of organisms are promoted, and further damaged bone cells are protected and repaired; the raw materials of the provided polypeptide composition are all derived from edible nutrient substances, toxic and harmful chemical reagents are not used in the extraction process, the safety is high, and the application range is wide; the polypeptide composition provided by the invention is reasonable in component preparation proportion, has a complementary gain effect, and does not need to worry about causing other toxic and side effects while increasing the bone mineral density; the provided polypeptide composition is fine and smooth in taste and pleasant in taste, the effect is better when the polypeptide composition is mixed with warm boiled water with the temperature not exceeding 60 DEG C, 5-10 g / kg of the polypeptide composition is eaten every day outside meals, and the polypeptide composition can be eaten by consumers who have little meals or only eat staple food in a proper amount.

Description

Technical Field

[0001] The present invention relates to the technical field of food health care, in particular to a polypeptide composition for increasing bone density and a preparation method thereof. Background Art

[0002] Bone density stands for bone mineral density, which is an important indicator of bone strength and bone quality. It reflects the degree of osteoporosis and is expressed in grams per cubic centimeter. It is an absolute value. Since different bone density detectors obtain different absolute values, T value and Z value are usually used clinically to determine whether bone density is normal. T value is a relative value that reflects the difference in bone density between the subject and young people. T value is between -1 and 1g / cm 3 It indicates that the bone density is normal, and the T value is between -1 and -2.5 g / cm 3 Between -2.5 g / cm2 and -2.5 g / cm2 respectively, indicating that bone mass is reduced. 3 The Z value represents the ratio of the subject's bone density to the average bone density of the same age, gender, and race. If the Z value is ≤ -2g / cm 3 It means that the bone density of the person being tested is lower than the standard for people of the same age.

[0003] Low bone density, or osteoporosis, is a bone disease characterized by decreased bone mass, damaged bone microstructure, and loose and fragile bone tissue. It has no obvious symptoms in the early stages and is easily ignored, so it is called a "silent disease" or a "silent epidemic." However, as the disease progresses, the harm gradually becomes apparent, mainly manifested in the proneness to fractures, thoracic vertebral deformity, hunchback, fatigue, back pain, bone pain and other discomfort symptoms, and may also lead to breathing difficulties, palpitations, chest tightness and shortness of breath, indigestion, muscle atrophy, psychological problems and other problems; and the risk of surgery after fracture is high and the success rate of healing is low.

[0004] At present, the treatment of osteoporosis is mainly through calcium supplementation and vitamin D, as well as infusion or administration of drugs that inhibit osteoclasts, sex hormone supplements, and selective estrogen receptor modulators. Due to large individual differences, there is no absolute best, fastest, and most effective medication. In addition to commonly used over-the-counter drugs, the most appropriate drug should be selected under the guidance of a doctor in full consideration of personal circumstances. These therapeutic drugs all have toxic side effects and are not suitable for long-term use. In addition, some drugs have strict conditions for taking and cumbersome methods of taking: For example, people with hypercalcemia cannot take calcium and vitamin D for treatment. If other suitable people take excessive calcium supplements, it will cause a series of side effects such as digestive system problems, hypercalcemia, urinary system stones, kidney stones, cardiovascular disease, etc.; and vitamin D supplementation requires the detection of serum 250HD levels to monitor the vitamin D nutritional status of different patients or the same patient at different times, and to guide vitamin D supplementation; drugs that inhibit osteoclasts, such as bisphosphonates and etidronate disodium, have strict conditions for taking and cumbersome methods of taking, and they require liver, kidney, stomach, and intestinal function tests to meet the conditions before taking them. For example, etidronate disodium is used to treat postmenopausal or aging-related osteoporosis. The medicine is taken between meals for two weeks, and then stopped for 11 weeks before starting the second cycle.

[0005] Long-term medication will also produce a variety of side effects. For example, patients will feel upper abdominal pain, acid reflux, etc. Patients with gastrointestinal dysfunction should use it with caution, and "flu-like" symptoms will be obvious. If it is given by intravenous infusion, renal function must be tested before each dose. It is contraindicated for those who do not meet the conditions. It is contraindicated for patients with severe oral diseases or those planning oral surgery. Long-term use of the drug for more than 3 years may cause thigh or groin pain.

[0006] Currently, osteoporosis health foods on the market all contain added calcium supplements, purified or synthetic minerals, vitamin mixtures, etc., which are all restricted to the applicable population and also involve certain risks, such as Chinese invention patents CN118717952A, CN118415341A, CN111068044A, CN103230014A, etc. Summary of the invention

[0007] The purpose of the present invention is to provide a polypeptide composition for increasing bone density and a preparation method thereof, so as to provide a polypeptide composition with few restrictions on the applicable population, no additional addition of synthetic preparations such as calcium mixtures, a complete food source, good effects, and no toxic side effects when consumed / taken for a long time.

[0008] To achieve the above object, the present invention provides a polypeptide composition for increasing bone density, comprising the following components in parts by weight: 5-10 parts of hawthorn extract, 5-20 parts of bovine collagen peptide complex, 5-20 parts of egg yolk small molecule peptide, 5-20 parts of cartilage extract, 5-10 parts of sesame extract, 1-5 parts of black bean powder, 1-5 parts of citrus fiber, and 2-5 parts of corn extract.

[0009] Preferably, the following components are included in parts by weight: 10 parts of hawthorn extract, 15 parts of bovine collagen peptide complex, 15 parts of egg yolk small molecule peptide, 17 parts of cartilage extract, 10 parts of sesame extract, 4 parts of black bean powder, 3 parts of citrus fiber, and 3 parts of corn extract.

[0010] Preferably, the following components are included in parts by weight: 10 parts of hawthorn extract, 20 parts of bovine collagen peptide complex, 20 parts of egg yolk small molecule peptide, 20 parts of cartilage extract, 10 parts of sesame extract, 5 parts of black bean powder, 5 parts of citrus fiber, and 5 parts of corn extract.

[0011] Preferably, the preparation method of hawthorn extract is as follows: wash and remove the seeds of fresh, disease-free and insect-free hawthorn, homogenize at 4°C, filter the filtrate, add protease for enzymolysis, and freeze-dry; the preparation method of egg yolk small molecule peptide is as follows: steam the eggs and take the egg yolk, disperse it in milk at 60°C, filter the filtrate, add pepsin for enzymolysis, filter with an inorganic nanofiltration ceramic membrane, and freeze-dry the filtrate.

[0012] Preferably, the preparation method of sesame extract is as follows: crush sesame seeds and add milk, extract at 60°C for 30min-1h, filter, add protease to the filtrate for enzymatic hydrolysis and filter, only retain polypeptides and amino acids with a molecular weight of no more than 1500 Daltons, and freeze-dry the filtrate.

[0013] Preferably, after the sesame seeds are ultrasonically crushed, 1 volume of milk is added, pepsin is added for enzymatic hydrolysis for 15 minutes, and the enzyme is inactivated at 80° C. for 5 minutes.

[0014] Preferably, the preparation method of cartilage extract is: take the cartilage part of the joint band of cattle bones and chicken cartilage, wash and remove impurities, crush into small pieces with a bone crusher, add distilled water for ultrasonic homogenization, extract at 100°C for more than 20 hours, sieve to remove lumps, cool to remove oil, add protease for enzymatic hydrolysis, collect polypeptides and amino acid solutions not greater than 1000 Daltons, and freeze-dry.

[0015] Preferably, the preparation method of citrus fiber is: homogenize fresh citrus pulp at low temperature, filter to obtain filter residue, dry at low temperature, and then grind; the preparation method of black bean powder is: fry insect-free and mildew-free black beans on low heat until they change color, and grind the beans and bean skins into powder.

[0016] Preferably, the preparation method of the corn extract is: adding fresh corn to 1 volume of drinking water, ultrasonically crushing the slurry, filtering the filtrate, adjusting the pH of the filtrate to 2 with hydrochloric acid, stirring and reacting for 20-30 minutes, collecting precipitate I for later use, adjusting the pH of the filtrate to 6.8-7.0 with hydrochloric acid, collecting precipitate II, and drying the filtrate at low temperature. The solids, precipitate I and precipitate II obtained by drying are crushed through a 100-mesh sieve.

[0017] A method for preparing the above-mentioned polypeptide composition for increasing bone density comprises weighing various raw materials according to the formula, putting them into a sterile mixer and mixing them evenly, and then drying, canning, packaging and storing them.

[0018] The egg yolk small molecule peptide, sesame extract, and black bean powder prepared by the method provided by the present invention are rich in lecithin, fat-soluble vitamins, vitamin D, and calcium; hawthorn extract, corn extract, and citrus fiber contain a large amount of minerals and water-soluble vitamins; hawthorn extract and citrus fiber also contain a large amount of organic acids; bovine collagen peptide complex, egg yolk small molecule peptide, and cartilage polypeptide extract contain small molecule peptides and a variety of amino acids. The solubility of calcium in the composition is greatly increased under an organic acid environment, and it can also form a chelate with the organic acid and / or amino acid in the component to promote the body's calcium absorption; the collagen peptides in the bovine collagen peptide complex and cartilage extract form a comprehensive interlaced network structure, and have good viscosity, which can adhere to the absorbed calcium, lecithin, inorganic minerals, and vitamin D, so that it can be better deposited in the bone microstructure, thereby effectively supplementing the minerals and bone lost by the bones, repairing the damaged bone microstructure, and increasing bone density.

[0019] In adulthood, organic matter accounts for about 1 / 3 of the bones, while inorganic matter accounts for about 2 / 3, making the bones of healthy adults both hard and elastic. The bovine bone collagen peptide complex, egg yolk small molecule peptide, and cartilage polypeptide extract in the composition provide the organic matter required for bones to maintain toughness, including collagen fibers and mucopolysaccharides, which maintain the moisture and elasticity of cartilage and enable joints to move flexibly. In addition, it is also of key significance for bone tissue repair and bone cell regeneration, and synergizes with the organic matter of plant origin provided by the adhered multiple minerals, sesame extracts, and corn extracts in the components to achieve better results.

[0020] On the other hand, the rich vitamins in hawthorn extract, citrus extract and sesame extract, and the rich zinc, magnesium and isoflavones in sesame extract and black bean powder can not only promote or directly participate in the synthesis of mucopolysaccharides, but also inhibit the decomposition of mucopolysaccharides, thereby promoting the resynthesis of mucopolysaccharides in bones.

[0021] The anthocyanins in black beans and the rich vitamin E in sesame extract help to remove free radicals from damaged areas, provide protection for the bones and digestive system to prevent further deterioration. In addition, the hawthorn extract provides a stomachic and digestive effect, which together protects the digestive system and thereby improves the body's absorption and metabolic capacity.

[0022] The polypeptide composition for increasing bone density provided by the present invention is not used for diagnosis and treatment of diseases.

[0023] Therefore, the present invention provides a polypeptide composition for increasing bone density and a preparation method thereof, and its specific technical effects are as follows: (1) Continuous administration of the polypeptide composition provided by the present invention can significantly increase the calcium content, phosphorus content and bone density of osteoporotic rats, promote the absorption and metabolism of nutrients in the body, and thus protect and repair damaged bone cells; (2) The raw materials of the polypeptide composition provided by the present invention are all derived from edible nutrients, and no toxic or harmful chemical reagents are used in the extraction process, so the polypeptide composition has high safety and wide application range; (3) The peptide composition provided by the present invention has a reasonable formulation ratio of each component and has a complementary gain effect. There is no need to worry about causing other toxic side effects while increasing bone density; (4) The polypeptide composition provided by the present invention has a delicate taste and pleasant flavor. It has a better effect when taken with warm water not exceeding 60°C. 5-10 g / kg can be taken orally every day outside of meals. Consumers who eat less or only eat staple foods can take more in appropriate amounts. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further illustrated by the following examples.

[0025] In order to make the purpose, technical scheme and advantages of the present application clearer, more thorough and complete, the technical scheme of the present invention is clearly and completely described below by examples. The following detailed description is the description of the embodiments, and is intended to provide further detailed description of the present invention. Unless otherwise specified, all technical terms used in the present invention have the same meaning as those generally understood by those skilled in the art to which the present application belongs.

[0026] Unless otherwise defined, the instruments, equipment, reagents and materials used in the examples were obtained from commercial sources.

[0027] A polypeptide composition for increasing bone density comprises the following components in parts by weight: 5-10 parts of hawthorn extract, 5-20 parts of bovine collagen peptide complex, 5-20 parts of egg yolk small molecule peptide, 5-20 parts of cartilage extract, 5-10 parts of sesame extract, 1-5 parts of black bean powder, 1-5 parts of citrus fiber, and 2-5 parts of corn extract.

[0028] The preparation method of hawthorn extract is as follows: wash and remove the seeds of fresh, disease-free and insect-free hawthorn, homogenize at 4°C, and let stand at 4°C for 4 hours, first absorb the supernatant, then filter with double-layer filter paper to obtain the filtrate, add trypsin to enzymatically hydrolyze at 37°C for 10 minutes, and freeze-dry.

[0029] The preparation method of egg yolk small molecule peptide is as follows: steam the eggs and take out the egg yolk, disperse it in 60°C milk, filter the filtrate, add pepsin to hydrolyze the filtrate when it drops to 37°C for 30 minutes, filter it with an inorganic nanofiltration ceramic membrane, and only retain polypeptides and amino acids with a molecular weight of no more than 1500 Daltons, and freeze-dry the filtrate.

[0030] The preparation method of cartilage extract is as follows: take the cartilage part of the joint band of bovine bone and chicken cartilage, wash and remove impurities, the mass ratio of the cartilage part of the joint band of bovine bone to chicken cartilage is 10:1, use a bone crusher to crush into pieces less than 1 cm, add distilled water to cover the bone pieces, ultrasonicate for 10 minutes, then extract at 100°C for 24 hours, filter the filtrate with a 60-mesh sieve, cool to 4°C, remove surface grease, add pepsin (the enzyme activity unit of pepsin is 3000U, and the addition amount is 1% of the solution mass) to the solution, enzymatically hydrolyze for 30 minutes at 37°C, and then filter with an inorganic nanofiltration ceramic membrane to obtain a polypeptide and amino acid solution of no more than 1000 Daltons, and freeze-dry the solution.

[0031] The preparation method of sesame extract is as follows: crush sesame seeds and add milk, extract at 60°C for 30 minutes, filter, add pepsin to the filtrate for 10 minutes, inactivate the enzyme at 80°C for 5 minutes, filter with an inorganic nanofiltration ceramic membrane, retain only polypeptides and amino acids with a molecular weight of no more than 1500 Daltons, and freeze-dry the filtrate.

[0032] The preparation method of black bean powder is as follows: stir-fry insect-free and mold-free dry black beans on low heat until the beans under the skin turn slightly yellow but not mushy, stop frying, grind the beans and bean skins into powder, and pass through a 100-mesh sieve.

[0033] The preparation method of citrus fiber is as follows: fresh citrus pulp is homogenized at low temperature, filtered to obtain filter residue, dried at 0°C, and then crushed to pass through a 100-mesh sieve.

[0034] The preparation method of the corn extract is as follows: adding fresh corn to 1 times the volume of drinking water, ultrasonically crushing the slurry, filtering the filtrate, adjusting the pH of the filtrate to 2 with hydrochloric acid, stirring and reacting for 20-30 minutes, collecting precipitate I for later use, adjusting the pH of the filtrate to 6.8-7.0 with hydrochloric acid, collecting precipitate II, and drying the filtrate at low temperature by rotary drying, and crushing the solid, precipitate I and precipitate II obtained by rotary drying through a 100-mesh sieve.

[0035] Example 1 A polypeptide composition for increasing bone density comprises: 10 parts of hawthorn extract, 15 parts of bovine collagen peptide complex, 15 parts of egg yolk small molecule peptide, 17 parts of cartilage extract, 10 parts of sesame extract, 4 parts of black bean powder, 3 parts of citrus fiber, and 3 parts of corn extract, and the components are mixed evenly.

[0036] Example 2 A polypeptide composition for increasing bone density comprises: 10 parts of hawthorn extract, 20 parts of bovine collagen peptide complex, 20 parts of egg yolk small molecule peptide, 20 parts of cartilage extract, 10 parts of sesame extract, 5 parts of black bean powder, 5 parts of citrus fiber, and 5 parts of corn extract, and the components are mixed evenly.

[0037] Example 3 A polypeptide composition for increasing bone density comprises: 5 parts of hawthorn extract, 15 parts of bovine collagen peptide complex, 15 parts of egg yolk small molecule peptide, 10 parts of cartilage extract, 5 parts of sesame extract, 2 parts of black bean powder, 2 parts of citrus fiber, and 3 parts of corn extract. The components are mixed evenly.

[0038] Comparative Example 1 15 parts of bovine collagen peptide complex, 15 parts of egg yolk small molecule peptide, 10 parts of sesame extract, 4 parts of black bean powder, 3 parts of citrus fiber, and 3 parts of corn extract.

[0039] Comparative Example 2 10 parts of hawthorn extract, 15 parts of bovine collagen peptide complex, 15 parts of egg yolk small molecule peptide, 4 parts of black bean powder, 3 parts of citrus fiber, and 3 parts of corn extract.

[0040] Comparative Example 3 10 parts of hawthorn extract, 15 parts of bovine collagen peptide complex, 15 parts of egg yolk small molecule peptide, 10 parts of sesame extract, 4 parts of black bean powder, 3 parts of citrus fiber, and 3 parts of corn extract.

[0041] Effect test 10 g of the polypeptide composition of Examples 1, 2, 3 and Comparative Examples 1, 2, 3 were taken respectively, and 10 mL of distilled water was added to prepare a solution, and 5 mL of the solution was taken respectively for in vivo experiments in mice.

[0042] (1) Calcium absorption test: SD female rats weighing 260 ± 5g were selected and ovariectomized to establish an osteoporosis rat model. After adapting to growth for 1 week, they were caged for 4 weeks, fed with the same basic feed, and drank deionized water. Measure height and weight once a week. Rats were randomly divided into 7 groups, including 6 experimental groups and 1 control group, with 6 rats in each group. Each experimental group was fed 5mL of the polypeptide composition solution of Examples 1, 2, 3 or Comparative Examples 1, 2, 3 at noon every day, and the control group was fed 5mL of distilled water at noon every day. The other conditions of the experimental group and the treatment group were the same, and they were fed for 30 days in total. The food intake was recorded 3 days before the end of the feeding experiment, and the feces were collected for 72 hours. The calcium and phosphorus contents in the feed and feces were determined by atomic absorption spectrophotometry.

[0043] Calcium intake (mg / d) = calcium content in feed (mg / g) × feed consumption (g / d); Fecal calcium (mg / d) = fecal calcium content (mg / g) × fecal excretion (g / d); Apparent absorption rate of calcium (%) = (intake calcium - fecal calcium) / intake calcium × 100%.

[0044] The calculation method of the apparent absorption rate (%) of phosphorus is the same as that of calcium. The results are shown in Table 1: Table 1 ; Among them, ** indicates that the difference is extremely significant compared with the average value of comparative examples 1, 2, and 3.

[0045] As can be seen from Table 1, the absorption rates of calcium and phosphorus by rats fed with the polypeptide compositions prepared in Examples 1, 2, and 3 are higher than those by rats fed with Comparative Examples 1, 2, and 3, indicating that the polypeptide compositions provided by the present invention can significantly promote the absorption of calcium and phosphorus by rats. The group of rats fed with no hawthorn extract (Comparative Example 1) has the worst absorption of calcium and phosphorus, and no sesame extract (Comparative Example 2) or no cartilage extract (Comparative Example 3) will affect the absorption of calcium and phosphorus by rats. Therefore, the polypeptide compositions provided by the present invention can cooperate with each other and work together to promote the absorption and utilization of calcium and phosphorus by rats.

[0046] (2) Bone calcium and bone density test: The experiment was continued using the rats in (1). The rats in (1) were fed for another 90 days and then killed. The left femur was removed and the bone calcium and bone phosphorus contents were determined by atomic absorption spectrometry. The right femur was then stripped and the bone density at the midpoint and distal end of the femur was determined by a bone densitometer.

[0047] Mark the distal end of the femur and the midpoint of the femur to determine the measurement point. Determine the measurement point of the midpoint of the femur: measure the entire length of the femur, pass through the midpoint, and draw a straight line along the cross-sectional direction. This is the measurement point of the midpoint of the femur (cross section). Determine the measurement point of the distal end of the femur: determine the measurement point at the lowest edge of the articular groove of the distal end of the femur, and draw a straight line through this point parallel to the mark at the midpoint of the femur. This is the measurement point of the distal end of the femur (cross section).

[0048] The results are shown in Table 2: Table 2 ; Among them, ** indicates that the difference is extremely significant compared with the average value of comparative examples 1, 2, and 3.

[0049] As can be seen from Table 2, the bone calcium content and bone density of rats in Examples 1, 2, and 3 are significantly greater than those in rats in Comparative Examples 1, 2, and 3, indicating that the polypeptide composition provided by the present invention has the effect of significantly increasing bone calcium and bone density, and the hawthorn extract, sesame extract, and cartilage extract in the polypeptide composition play an important role in the synergistic effect of each component. The rats fed with the polypeptide composition prepared in Example 2 had the highest bone calcium content and bone density, but the differences between different individuals were relatively large. During the 120 days of feeding, the rats fed with Examples 1, 2, 3 and Comparative Examples 1, 2, and 3 had no abnormal stool or urine, and no other abnormal manifestations were observed.

[0050] Therefore, continuous administration of the polypeptide composition provided by the present invention can significantly increase the calcium content, phosphorus content and bone density of the bones of osteoporotic rats, promote the absorption and metabolism of nutrients in the body, and further protect and repair damaged bone cells; the raw materials of the polypeptide composition provided are all derived from edible nutrients, and no toxic or harmful chemical reagents are used in the extraction process, so the polypeptide composition has high safety and a wide range of applications; the formulation ratio of each component of the polypeptide composition provided is reasonable, and the polypeptide composition has a complementary gain effect, and there is no need to worry about causing other toxic and side effects while increasing bone density; the polypeptide composition provided has a delicate taste and a pleasant taste, and the effect is better when taken with warm boiled water not exceeding 60°C, and 5-10 g / kg can be consumed or taken every day outside of meals, and consumers who eat less or only eat staple foods can take more in appropriate amounts.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A polypeptide composition for increasing bone density, characterized in that: The invention comprises the following components in parts by weight: 5-10 parts of hawthorn extract, 15-20 parts of bovine collagen peptide complex, 15-20 parts of egg yolk small molecule peptide, 10-20 parts of cartilage extract, 5-10 parts of sesame extract, 2-5 parts of black bean powder, 2-5 parts of citrus fiber and 3-5 parts of corn extract.

2. A polypeptide composition for increasing bone density according to claim 1, characterized in that: The invention comprises the following components in parts by weight: 10 parts of hawthorn extract, 15 parts of bovine collagen peptide complex, 15 parts of egg yolk small molecule peptide, 17 parts of cartilage extract, 10 parts of sesame extract, 4 parts of black bean powder, 3 parts of citrus fiber and 3 parts of corn extract.

3. A polypeptide composition for increasing bone density according to claim 1, characterized in that: The invention comprises the following components in parts by weight: 10 parts of hawthorn extract, 20 parts of bovine collagen peptide complex, 20 parts of egg yolk small molecule peptide, 20 parts of cartilage extract, 10 parts of sesame extract, 5 parts of black bean powder, 5 parts of citrus fiber and 5 parts of corn extract.

4. A polypeptide composition for increasing bone density according to claim 1, characterized in that: The preparation method of hawthorn extract is as follows: wash and remove the seeds of fresh, disease-free and insect-free hawthorn, homogenize at 4°C, filter the filtrate, add protease for enzymolysis, and freeze-dry; the preparation method of egg yolk small molecule peptide is as follows: steam the eggs and take the egg yolk, disperse it in 60°C milk, filter the filtrate, add pepsin for enzymolysis, filter it with an inorganic nanofiltration ceramic membrane, and freeze-dry the filtrate.

5. A polypeptide composition for increasing bone density according to claim 1, characterized in that: The preparation method of sesame extract is as follows: crush sesame seeds and add milk, extract at 60°C for 30min-1h, filter, add protease to the filtrate for enzymatic hydrolysis and then filter, only retain polypeptides and amino acids with a molecular weight of no more than 1500 Daltons, and freeze-dry the filtrate.

6. A polypeptide composition for increasing bone density according to claim 5, characterized in that: After ultrasonic crushing, 1 volume of milk was added to the sesame seeds, followed by enzymatic hydrolysis with pepsin for 15 min and enzyme inactivation at 80 °C for 5 min.

7. A polypeptide composition for increasing bone density according to claim 1, characterized in that: The preparation method of cartilage extract is as follows: take the cartilage part of the joint band of bovine bones and chicken cartilage, wash and remove impurities, crush into small pieces with a bone crusher, add distilled water for ultrasonic homogenization, extract at 100°C for more than 20 hours, sieve to remove lumps, cool to remove grease, add protease for enzymatic hydrolysis, collect polypeptides and amino acid solutions not greater than 1000 Daltons, and freeze-dry.

8. A polypeptide composition for increasing bone density according to claim 1, characterized in that: The preparation method of citrus fiber is as follows: fresh citrus pulp is homogenized at low temperature, filtered to obtain filter residue, dried at low temperature, and then crushed; the preparation method of black bean powder is as follows: insect-free and mildew-free black beans are fried on low heat until they change color, and the beans and bean skins are ground into powder.

9. A polypeptide composition for increasing bone density according to claim 1, characterized in that: The preparation method of the corn extract is as follows: adding fresh corn to 1 times the volume of drinking water, ultrasonically crushing the slurry, filtering the filtrate, adjusting the pH of the filtrate to 2 with hydrochloric acid, stirring and reacting for 20-30 minutes, collecting precipitate I for later use, adjusting the pH of the filtrate to 6.8-7.0 with hydrochloric acid, collecting precipitate II, and drying the filtrate at low temperature by rotary drying, and crushing the solid, precipitate I and precipitate II obtained by rotary drying through a 100-mesh sieve.

10. A method for preparing a polypeptide composition for increasing bone density according to any one of claims 1 to 9, characterized in that: Weigh the raw materials of each component according to the formula, put them into a sterile mixer and mix them evenly, then dry, can and package them for storage.