JP7513390B2 - Composition for improving obesity and composition for improving type II diabetes - Google Patents

Description

The present invention relates to a composition for improving obesity and a composition for improving type II diabetes that contain ingredients derived from rice bran.

Generally, rice bran is a composition of pericarp, seed coat, germ, etc. obtained in the process of polishing brown rice, and has long been used as a raw material for rice bran oil and as a rice bran bed for rice bran pickles. Rice bran is also known to contain useful components such as phytic acid and ferulic acid, which have antitumor and antioxidant effects, and γ-oryzanol, which has effects such as improving menopausal disorders and absorbing ultraviolet rays. Therefore, rice bran has traditionally been used as a raw material for pharmaceuticals, cosmetics, etc., in addition to being a nutritious health food.

In addition, in recent years, as disclosed in, for example, Patent Documents 1 and 2, it has been found that by treating rice bran with a specific protease, it is possible to improve beneficial effects on the body, such as ACE inhibitory activity.

Patent No. 6296722 Patent No. 6462100

The object of the present invention is to provide a composition for improving obesity that has an excellent effect of improving obesity. Another object of the present invention is to provide a composition for improving type II diabetes that has an excellent effect of improving type II diabetes.

The present invention is based on the discovery that thermolysin-treated rice bran exhibits excellent effects of improving obesity and type II diabetes.
In order to achieve the above-mentioned object, one embodiment of the present invention provides a composition for improving obesity, which is characterized by containing rice bran treated with thermolysin.

The thermolysin-treated product may contain at least one selected from SEQ ID NO: 1 and Leu-Arg-Ala.
The thermolysin-treated product is obtained by subjecting compressed and defatted rice bran to a thermolysin treatment, and may be a water-soluble fraction.

The improvement in obesity may be a reduction in white adipose tissue.
Another aspect of the present invention is a composition for improving type II diabetes mellitus, which is characterized by containing rice bran treated with thermolysin.

The improvement in type II diabetes may be an improvement in glucose metabolism or an improvement in insulin resistance.

The present invention can provide an excellent effect of improving obesity. In addition, the present invention can provide an excellent effect of improving type II diabetes.

Graph showing changes in body weight from 7 to 25 weeks of age in individuals from each test group. Graph showing test food intake in individuals in each test group. Graph showing changes in blood glucose levels in individuals of each test group during a glucose tolerance test. Graph showing changes in blood glucose levels of individuals in each test group during an insulin tolerance test. Graph showing white adipose tissue mass in each test group population. Graph showing brown adipose tissue mass in each test group population. Graph showing liver mass in each study group population.

First Embodiment
Hereinafter, a first embodiment of the obesity-improving composition of the present invention will be described. The rice bran used as the raw material of the thermolysin-treated rice bran contained in the obesity-improving composition of this embodiment is not particularly limited, and may be, for example, rice bran itself or defatted rice bran. Examples of defatted rice bran include pressed defatted rice bran defatted by pressing, and extracted defatted rice bran extracted using an organic solvent. Among these raw materials, pressed defatted rice bran is preferred. Examples of a method for producing pressed defatted rice bran include a method in which the rice bran obtained after polishing (raw rice bran) is first heated to inactivate lipase (lipase inactivation treatment), and then pressed.

Lipase inactivation treatment is carried out for the purpose of preventing oxidation deterioration of rice bran (raw rice bran) containing about 18 to 20% by mass of lipids. Usually, raw rice bran is heated and roasted at about 70 to 130°C. Compression treatment can be carried out by a known pressing method, for example, a method in which rice bran that has been heated and roasted to about 100 to 115°C is pressed using a low-temperature continuous press (for example, Technosigma's Miracle Chamber). It is preferable to press until the lipid content in the defatted rice bran after pressing is about 5 to 20% by mass. In addition, a drying treatment may be carried out for the purpose of reducing the moisture content of the rice bran before the lipase inactivation treatment and the defatted rice bran after oil extraction. Furthermore, it is preferable to crush and classify the pressed and defatted rice bran by a known method to make it into a powder form. In this case, the average particle size of the powder is preferably 5 to 200 μm, more preferably 10 to 150 μm, and most preferably 40 to 100 μm. The average particle size can be measured by a sieve method. The lipid content in the defatted rice bran is not particularly limited, but is preferably 5 to 20% by mass, and more preferably 7 to 15% by mass. The defatted rice bran may be a commercially available product. An example of a commercially available product is Hybref (manufactured by Sunbran).

Thermolysin is a neutral metalloprotease derived from Bacillus thermoproteolyticus, and has the EC number 3.4.24.27. Thermolysin may be extracted and purified from the above microorganisms, may be biochemically synthesized, or may be a commercially available product. Examples of commercially available products include those manufactured by Peptide Institute, Inc., and Wako Pure Chemical Industries, Ltd.

The treatment conditions for obtaining a thermolysin-treated product are not particularly limited as long as they are conditions under which thermolysin activity can be obtained, and various conditions such as temperature, pH, and time can be set appropriately. As a treatment method, for example, water is added as a solution to the rice bran raw material, and after adjusting the pH if necessary, a predetermined amount of thermolysin is added. The amount of thermolysin added can be set appropriately taking into consideration the treatment conditions, the ratio to the raw material, the enzyme activity, etc. As the rice bran raw material for the thermolysin treatment, rice bran or defatted rice bran as the rice bran raw material may be used as is, or a water extract (water-soluble fraction) of the rice bran raw material may be used. The water extract of the rice bran raw material is a liquid composition (consisting of water and extracted rice bran components) obtained by extracting the rice bran raw material with water. The water extraction conditions are not particularly limited, but an example is a method in which the rice bran raw material is soaked (or stirred) in water at about 10 to 50°C for about 1 to 24 hours.

Thermolysin treatment conditions include, for example, mixing the rice bran raw material and thermolysin with water, and reacting for about 10 to 30 hours with gentle stirring at about 37°C. After this treatment, the thermolysin may be inactivated. Thermolysin inactivation treatment can be performed, for example, by heating (e.g., treatment at 100°C for about 10 to 20 minutes).

The thermolysin treated product is a composition obtained by treating rice bran with thermolysin as described above, and is a composition containing hydrolysins (particularly peptides) of proteins derived from rice bran that have been reduced in molecular weight by thermolysin. Such peptides preferably include those of about 10 kDa or less. More specifically, it is more preferable that they contain at least one type selected from SEQ ID NO: 1 (Val-Tyr-Thr-Pro-Gly) and Leu-Arg-Ala.

When the solution after thermolysin treatment contains oil, it is preferable to extract a water-soluble fraction that further contains rice bran protein hydrolysates. Such a water-soluble fraction contains components that exert an obesity-improving effect and an effect of improving type II diabetes, which will be described later. The water-soluble fraction can be obtained, for example, by centrifuging the solution after thermolysin treatment. It is also preferable to filter the solution after thermolysin treatment to remove the insoluble fraction and recover the filtrate.

The form of use of the thermolysin-treated rice bran product is not particularly limited, and the treated liquid obtained as described above may be applied as it is in liquid form as a composition for reducing obesity, or it may be applied as a concentrated liquid concentrated by distillation or the like, or it may be applied in the form of a solid product dried by freeze-drying or the like.

The obesity-improving composition containing thermolysin-treated rice bran is used to improve obesity, and exerts an excellent obesity-improving effect, particularly when taken orally. Obesity refers to a state in which body weight is greater than normal and in which body fat has accumulated excessively. The obesity-improving composition of this embodiment is not only used to improve obesity, but also includes applications aimed at preventing or delaying the worsening of symptoms and preventing obesity in healthy individuals.

Mature fat cells that make up adipose tissue in the living body are broadly divided into two types: brown fat cells and white fat cells. White fat cells are fat cells that have the function of storing fat, and are known to break down fat in order to compensate for the lack of energy when the body is in an energy-deficient state, such as when fasting. On the other hand, brown fat cells are known to oxidize and break down fat even under normal conditions. Most fat cells in adults are white fat cells, which are widely distributed as subcutaneous fat, visceral fat, etc., and accumulate excess energy in the body as fat. The obesity-improving composition of this embodiment reduces white fat cells in particular, and reduces excess body fat such as subcutaneous fat and visceral fat, thereby improving the obese state.

The obesity-improving composition of this embodiment may be used to improve, prevent the worsening, or prevent various obesity-related diseases. Application of the obesity-improving composition is expected to improve obesity and improve various obesity-related diseases. Examples of obesity-related diseases include diabetes, arteriosclerosis, impaired glucose tolerance, metabolic syndrome, hypertension, hyperlipidemia, hypertriglyceridemia, hypercholesterolemia, liver disease, and periodontal disease (gingivitis, periodontitis).

The application form of the composition for improving obesity is not particularly limited, and it can be applied, for example, as a food or drink, a medicine, or a quasi-drug. The thermolysin-treated rice bran may be used as it is as a food or drink or a medicine ingredient, or may be made into a product by appropriately mixing it with a carrier, additive, etc. that is pharmacologically or food hygienically acceptable.

When the obesity-improving composition of this embodiment is applied to food and beverages such as food and beverages, it can be applied to, for example, food additive compositions, various confectioneries, gums, tablets, capsules (soft capsules, hard capsules), various processed foods, various beverages, etc. The form can be appropriately designed according to the material to which it is applied, and can be configured as, for example, a solid such as a powder or granules, a paste, a liquid, etc.

The uses of the food and drink are not particularly limited, and can be so-called general foods, health foods, functional foods, nutritional supplements, supplements, foods for the sick, foods for specific uses, foods with health functions, foods with nutritional functions, foods for specific health uses, foods with functional claims, etc. Furthermore, it may be applied as diet foods, beauty foods, foods for exercise therapy, and foods for treating obesity. When the use is indicated in the food and drink, indications stipulated by various laws, enforcement regulations, guidelines, etc. can be mentioned. In the case of foods and drinks, indications of use include indications on packages such as wrapping and containers, as well as indications on advertising media such as pamphlets. The indications of use of the obesity improving composition of this embodiment include indications of improvement, prevention, prevention of aggravation, or delay of symptoms of obesity, as well as indications of improvement, prevention, prevention of aggravation, or delay of symptoms of various diseases related to obesity described above. In addition, indications suggesting these improvement, prevention, prevention of aggravation, or delay of symptoms are also included. For example, expressions such as reducing or inhibiting the loss or gain of body fat, body fat percentage, blood triglycerides, subcutaneous fat, abdominal fat, visceral fat, etc., reducing or inhibiting the loss or gain of weight, lowering body mass index (BMI), improving a high BMI value, improving body shape, helping to reduce waist circumference, etc. can be used.

When the obesity-improving composition of this embodiment is used as a drug or quasi-drug, it can be administered by ingestion (oral ingestion) or enteral administration. The dosage form is not particularly limited, and may be, for example, a powder, powder, granules, tablet, capsule, pill, suppository, liquid, etc. Furthermore, excipients, bases, emulsifiers, solvents, stabilizers, etc. may be added as additives.

The action and effect of the composition for reducing obesity of this embodiment will be described.
(1) Generally, obesity refers to a state in which one weighs more than normal or in which body fat has accumulated excessively. Recently, it has become possible to quantitatively grasp obesity using BMI as an index. There are various causes of obesity, but it is often caused by lifestyle habits such as high-calorie diet, drinking, smoking, lack of exercise, and stress. Obesity is known as a risk factor for arteriosclerosis, which is believed to be the cause of adult diseases such as myocardial infarction and cerebral infarction, and has become a serious social problem. The current situation is that no fundamental treatment for the symptoms of obesity has been established other than improving diet and moderate exercise. Since obese people have a higher risk of developing myocardial infarction and cerebral infarction than healthy people, there is currently an urgent need to develop compositions for preventing and improving obesity.

The obesity-reducing composition of this embodiment is configured to contain thermolysin-treated rice bran. Because it is a naturally derived ingredient, it can be safely applied to the living body and has an excellent effect of reducing obesity.

Second Embodiment
The second embodiment of the composition for improving type II diabetes mellitus of the present invention will be described below. The differences from the first embodiment will be mainly described below. The thermolysin-treated rice bran used in the composition for improving type II diabetes mellitus of this embodiment is the same as that of the first embodiment.

The composition for improving type II diabetes of this embodiment is applied to improve type II diabetes, and exerts an excellent effect of improving type II diabetes, especially when taken orally. In particular, the symptoms of type II diabetes are improved by improving glucose metabolism or insulin resistance. Type II diabetes is a disease in which blood glucose and hemoglobin A1c values exceed a predetermined standard, but in this embodiment, it also includes people whose blood glucose and hemoglobin A1c values are higher than normal, such as so-called prediabetic people. Improvement of glucose metabolism refers to, for example, improvement of blood glucose and hemoglobin A1c (HA1c) values. In addition, the composition for improving type II diabetes of this embodiment is not only applied to patients with the aim of improving symptoms related to type II diabetes, but also includes applications aimed at preventing or delaying the worsening of symptoms and preventing type II diabetes in healthy people.

The type II diabetes improving composition of this embodiment may be used to improve, prevent, or prevent various complications of diabetes associated with type II diabetes. Application of the type II diabetes improving composition is expected to improve diabetes and improve complications. Examples of diabetic complications include diabetic neuropathy, diabetic retinopathy, and diabetic nephropathy.

The application form of the composition for improving type II diabetes is the same as that of the first embodiment. When applied to food and beverages, the contents of the indication of the use of the composition for improving type II diabetes include indication of improvement, prevention, prevention of aggravation, or delay of symptoms of type II diabetes, as well as indication of improvement, prevention, prevention of aggravation, or delay of symptoms of the above-mentioned complications. Indications suggesting such improvement, prevention, prevention of aggravation, or delay of symptoms are also included. For example, expressions such as improvement of blood glucose level or HA1c level, prevention of aggravation, gradual rise in blood glucose level after meals, and for those who are concerned about blood glucose level may be mentioned.

The action and effect of the composition for improving type II diabetes of this embodiment will be described.
(2) The composition for improving type II diabetes mellitus of this embodiment is configured to contain rice bran treated with thermolysin. Since it is a naturally derived component, it can be safely applied to the living body and can exert an excellent effect of improving type II diabetes.

The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other as long as they are not technically inconsistent.
The composition for improving obesity or the composition for improving type II diabetes in the above embodiment may be applied to domestic animals other than humans.

- In the obesity-improving composition or type II diabetes-improving composition of the above embodiment, the amount of thermolysin-treated rice bran contained in the medicine, quasi-drug, or food or drink is not particularly limited as long as the effects of the present invention are obtained, and can be configured to contain, for example, 0.1 to 100% by mass, preferably 1 to 90% by mass, of the solid content. In addition, the daily intake amount and intake period can be appropriately set depending on the purpose, condition, etc.

- In the thermolysin-treated rice bran compounded in the obesity-improving composition or type II diabetes-improving composition of the above embodiment, when compressed and defatted rice bran is used as the raw material, γ-oryzanol, an oily component in the rice bran raw material, may be adjusted to, for example, 50 mg/100 g (solid content) or less, preferably 25 mg/100 g (solid content) or less.

The above embodiment will be described in more detail below with reference to test examples, but the present invention is not limited thereto.
Test Example 1: Effects of improving obesity and type II diabetes
(Preparation of thermolysin-treated rice bran)
The raw rice bran used was Hybref, a product name of Sanbran Co., Ltd. Hybref is pressed and defatted rice bran that has been defatted by squeezing rice bran. Thermolysin (Code 3504, manufactured by Peptide Institute Co., Ltd.) was used.

First, the rice bran raw material was mixed with ultrapure water to a concentration of 30 g/L, and thermolysin was added to this to a concentration of 0.4 g/L. The mixture was then incubated in a 37°C incubator at 250 rpm for 20 hours for enzyme treatment. The mixture was then immersed in a boiling water bath for 15 minutes to inactivate the enzyme. The mixture was then centrifuged at 15°C and 7150 rpm (8000 x g) for 15 minutes to separate the solid and liquid. The pH of the resulting supernatant was adjusted to 7.0 using NaOH, filtered using filter paper No. 2 (manufactured by Advantec), and the resulting filtrate was freeze-dried. The freeze-dried product was used as the rice bran thermolysin-treated product. It was confirmed by ultrafiltration that the rice bran thermolysin-treated product contained peptides of approximately 10 kDa or less. Furthermore, amino acid sequence analysis confirmed that it contains the peptide sequence of SEQ ID NO:1 and Leu-Arg-Ala.

(Mice and feed)
In vivo studies were performed using mice. NSY mice (Hoshino Laboratory Animal Breeding Center), which are mice that spontaneously develop type II diabetes, were used. NSY mice are characterized by mild obesity, visceral fat accumulation, and insulin resistance.

The test diet used was a high-fat diet, HFD-60 (manufactured by Oriental Yeast Co., Ltd.), consisting of the ingredients shown in Table 1 below. The high-fat diet containing thermolysin-treated rice bran was prepared by adding 0.04% by mass of the above-mentioned rice bran thermolysin-treated product based on the composition of HFD-60, as shown in Table 1.

The gamma-oryzanol content of the thermolysin-treated rice bran that was added to the high-fat diet and the pressed, defatted rice bran (Hybreh) that was used as the raw rice bran was measured using HPLC. The results are shown in Table 2.

(Rearing conditions and feeding)
First, after preliminary rearing on a normal diet (CE-2 solid), mice aged 4 weeks were fed only a high-fat diet (HFD-60) for 3 weeks. The weight of the mice aged 7 weeks was measured, and they were divided into two groups, a control group (n = 8) fed only a high-fat diet and an example group (n = 8) fed a high-fat diet containing a rice bran thermolysin-treated product, so that there was no significant difference in the average weight of each group. Thereafter, the control group was fed only a high-fat diet until the age of 26 weeks. On the other hand, the example group was fed a high-fat diet containing a rice bran thermolysin-treated product from 7 weeks to 26 weeks of age. During the rearing period, the mice were allowed to eat and drink freely, and the rearing environment was a 12-hour light/12-hour dark period. During the rearing period, the weight was measured every week, and the amount of food intake was also measured appropriately when food was replenished. In addition, in the glucose tolerance test described below, a separate group was prepared, and mice of the ages listed in the glucose tolerance test column were reared in the same manner.

Body weight changes were measured in each test group from 7 to 25 weeks of age. The mean ± standard error was calculated for each individual in each test group. The results are shown in Figure 1. In the figure, * indicates p<0.05, and § indicates p<0.1 (t-test).

In addition, the average intake (g/day) of the test food was calculated for each test group from 7 to 25 weeks of age. The average value ± standard error was calculated for each test group. The results are shown in Figure 2.
(Glucose tolerance test)
A glucose tolerance test was performed by the ipGTT method. First, mice (n=10-11) from each group aged 8-12 weeks were fasted overnight (15 hours), and then the tails of the animals were punctured and blood glucose levels were measured using a simple blood glucose meter (fasting blood glucose level). After measuring the fasting blood glucose level, 2 g/kg BW of glucose was administered intraperitoneally. At predetermined intervals after intraperitoneal administration of glucose, the tails were punctured in the same manner as for measuring the fasting blood glucose level, and blood glucose levels were measured using a simple blood glucose meter. The mean value ± standard error of blood glucose level was calculated for each test group. The results are shown in Figure 3. In addition, * in the figure indicates p<0.05 (t-test).

(Insulin Tolerance Test)
Insulin tolerance test was performed by ITT method. First, mice of each group (n=6-7) aged 26 weeks were fasted overnight (15 hours), and then the tails of the animals were punctured and blood glucose levels were measured using a simple blood glucose meter (fasting blood glucose level). After measuring the fasting blood glucose level, 0.5 U/kg insulin was administered intraperitoneally. At predetermined intervals after the intraperitoneal administration of insulin, the tails were punctured in the same manner as in the fasting blood glucose level measurement, and blood glucose levels were measured using a simple blood glucose meter. The average blood glucose level ± standard error was calculated for each test group, assuming that the blood glucose level at the start of measurement was 100. The results are shown in FIG. 4. In addition, * in the figure indicates p<0.05 (t-test).

(Measurement of mass of adipose tissue, etc.)
After the above test, blood was collected from the fundus under anesthesia with sevofren, and the liver, white adipose tissue, and brown adipose tissue were each extracted and weighed (g). The average value ± standard error was calculated for each test group. The weights of the liver, white adipose tissue, and brown adipose tissue for the control group and the example group are shown in Figures 5 to 7, respectively. * in the figures indicates p<0.05 (t-test).

(result)
As shown in FIG. 1, it was observed that the rate of weight gain at each week of age was significantly suppressed in the example group in which the rice bran thermolysin-treated product was added to the high-fat diet, compared to the control group.

As shown in FIG. 5, it was found that the mass of white adipose tissue was significantly reduced in the example group in which the rice bran thermolysin-treated product was added to a high-fat diet, compared to the control group.
In other words, the ingestion of the thermolysin-treated rice bran product was found to have an obesity-improving effect. As shown in Figure 2, no difference was observed in the amount of the test food intake between the control group and the example group.

As shown in Figure 3, in the glucose tolerance test, it was found that the increase in blood glucose level was significantly suppressed in the experimental group in which rice bran thermolysin-treated material was added to a high-fat diet compared to the control group.

As shown in Figure 4, in the insulin tolerance test, blood glucose levels did not decrease even when a strong insulin load of 0.5 U/kg was administered as in the control group, whereas blood glucose levels decreased significantly in the example group in which rice bran thermolysin-treated material was added to a high-fat diet. In addition to its obesity-improving effect, rice bran thermolysin-treated material was also found to have an effect of improving type II diabetes by improving glucose metabolism and insulin resistance.

As shown in Table 2, the thermolysin-treated rice bran product had a significantly lower γ-oryzanol content than pressed and defatted rice bran, suggesting that the obesity- and type II diabetes-improving effects were due to the involvement of components other than fat-soluble components.

<Prescription Examples>
The following is an example of a formulation using thermolysin-treated rice bran.
(Formulation Example 1: Tablets)
Rice bran thermolysin treated product: 10% by mass
Excipient (crystalline cellulose, etc.): 90% by mass
(Total 100% by mass)
(Formulation Example 2: Beverage)
Rice bran thermolysin treated product: 10% by mass
Fruit juice: 30% by mass
Water: 60% by weight
(Total 100% by mass)

Claims (6)

A composition for improving obesity, comprising thermolysin-treated rice bran which has not been subjected to a water extract separation process . The composition for improving obesity according to claim 1, wherein the thermolysin-treated product contains at least one selected from SEQ ID NO: 1 and Leu-Arg-Ala. The composition for improving obesity according to claim 1 or 2, wherein the thermolysin-treated product is a water-soluble fraction of compressed defatted rice bran that has been treated with thermolysin. The composition for improving obesity according to any one of claims 1 to 3, wherein the improvement in obesity is a reduction in white adipose tissue. A composition for improving type II diabetes accompanied by improvement in blood glucose level or hemoglobin A1c (HA1c) level, comprising thermolysin-treated rice bran that has not been subjected to bacterial fermentation treatment and water extract separation treatment . The composition for improving type II diabetes according to claim 5, wherein the improvement of type II diabetes is improvement of glucose metabolism or improvement of insulin resistance.