JPS6330890B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an oral or gastrointestinal nutrient containing a low-molecular-weight peptide composition containing dipeptides and tripeptides as main components. BACKGROUND ART Conventionally, peptides and amino acids have been produced by hydrolyzing proteins with enzymes, mainly in the food field. However, most of the objectives have been to solubilize proteins by decomposing them with enzymes, or to reduce the molecular weight of proteins to make them suitable as food materials, and to reduce the molecular weight of decomposition products. There were no problems at all. Conventional peptides have either a low degree of decomposition or an extremely high content of free amino acids.In other words, the degree of decomposition is uneven and the molecular weight ranges from tens of thousands to free amino acids, with an average molecular weight of several thousand or more. The amount of free amino acids was said to be 50% or more. The present inventors have found that peptide compositions with a narrow molecular weight range are better for digestion and absorption than conventional solubilized proteins or peptide mixtures or amino acid mixtures with a wide molecular weight distribution. It was confirmed that it is advantageous when used as a nutritional supplement from the viewpoint of nutrition and physiology. The low-molecular-weight peptide composition contained in the nutritional supplement of the present invention is mainly composed of deipeptides and tripeptides obtained by enzymatic hydrolysis using the whole protein raw material as a nitrogen source, and the content of peptides with a molecular weight of 700 or more is 20wt% or less. In addition, the free amino acid content is 20wt% or less, and the average molecular weight is
It is 550-300. This composition was obtained by controlling the molecular weight of the protein raw material as described above. Recently, it has been said that cypeptides and tripeptides are definitely absorbed quickly from the intestinal tract, and the present inventors confirmed this for the first time in vivo, as will be detailed later. In addition, the present inventors have confirmed that while free amino acid mixtures exhibit absorption variations due to antagonistic effects or low solubility, such absorption variations are not observed in the case of low-molecular-weight peptides. Therefore, the above-mentioned low-molecular-weight peptide composition is preferred as a protein source for nutritional supplements. The purpose of the present invention is to provide a low-molecular-weight peptide mainly composed of deipeptide, which has less mutual absorption antagonism among amino acids, has high solubility, and has a high total nitrogen absorption rate, resulting in a good nitrogen balance. We are trying to provide nutritional supplements containing. Another object of the present invention is to provide a low peptide-containing nutritional supplement that serves as a highly efficient nitrogen source to increase body weight and at the same time lower blood cholesterol levels. A further object of the present invention is to use the present invention as an oral nutritional supplement that reduces the digestive burden due to its low molecular weight, such as dipeptide or tripeptide, which has good absorption properties. The objective is to provide a gastrointestinal nutritional supplement that can be administered directly to humans. That is, the present invention provides an average amount of depeptides and tripeptides whose main components are peptides with a molecular weight of 700 or more and a free amino acid content of 20% or less and a free amino acid content of 20% or less obtained by enzymatic hydrolysis using the entire protein raw material as a nitrogen source. A nutritional supplement containing a low molecular weight peptide composition having a molecular weight of 550 to 300 is provided. The effects of the low-molecular-weight peptide composition containing dipeptide and tripeptide as main components used in the nutritional supplement of the present invention and the method for producing the same will be explained in detail below. Until now, attention has not been paid to peptides whose molecular weight is reduced within a limited range as in the present invention, and the production method thereof has not been sufficiently developed. A peptide composition with controlled molecular weight reduction was produced in high yield. [Production example] 5-20w/v% protein raw material (egg white) in water
Adjust the pH to 1 to 4 with acid, and simultaneously or sequentially dissolve any two enzymes selected from pepsin, morsin, and Sunprose F in an amount of 0.5 to 5 wt% or less based on the substrate. The enzyme is added to the solution and reacted at a temperature of 25 to 60°C for 20 to 30 hours to inactivate the enzyme, and the supernatant after centrifugation is dried. The yield of the product obtained is extremely high relative to the raw protein, with an average molecular weight of approximately 550 to 300, a free amino acid content of approximately 5 to 20 wt%, and a peptide content of 700 or more.
It is less than 20wt%. Note that the protein raw materials used in this specification include proteins originating from animals, plants, microorganisms, etc., as well as protein-like substances to which specific amino acids have been added by plastein reaction. The low-molecular-weight peptide composition thus obtained is used as a protein source (nitrogen source) in the nutritional supplement of the present invention. To confirm the effectiveness, a diet containing a nitrogen source with the same amino acid composition was prepared as shown in the table below.

[Table] The nitrogen sources in the table above are as follows. A... Egg white protein B... Average molecular weight 420 to be added to the nutritional supplement of the present invention,
Low-molecular-weight peptide composition C containing 8 wt% free amino acids...Free amino acid mixture D...Peptide composition having an average molecular weight of 1400 and 2 wt% free amino acids Ten Wistar rats were each allowed to freely consume a diet with the composition shown in the table for two weeks. The results were as shown in the table.

[Table] In the above table, Food efficiency indicates the ratio based on the respective Weight gain/Food intake values. From this test result, it was confirmed that the nutritional supplement of the present invention containing a low-molecular-weight peptide composition having dipeptides and tripeptides as main components has many efficacies as described below. (1) The amount of nitrogen retained in the body is more than 20% higher than that of (conventional peptide decomposition product) and significantly higher than that of (amino acid mixture). (2) As mentioned in (1), because the effective nitrogen utilization rate in the body is high, the food efficiency is more than 20% higher than other types, resulting in better growth and greater weight gain. . (3) When looking at the blood cholesterol level, it was found that it was significantly lowered, and it is inferred that it has the effect of relatively lowering cholesterol.
In order to investigate why the above-mentioned effects occur, we conducted in vivo absorption experiments using different nitrogen sources. Specifically, only a nitrogen source was forcibly injected into the stomachs of five Wistar rats through a tube, blood was collected from the portal vein, and a comparative test was conducted to determine the cut-off rate of increase in blood amino acid concentrations. The amino acid composition was made the same among the nitrogen source samples (), (), (), and () used. The results are shown in the table below. The values in the table are the average absorption rate of each amino acid until the absorption amount reaches its peak value. In addition, a sample with almost ideal amino acid composition () and the above sample ()
A comparison of amino acid absorption patterns with ~() is shown in Table 1.

【table】

[Table] It can be easily understood from the above test results (Table 1) that the low molecular weight peptide composition used in the nutritional supplement of the present invention has the following effects. (1) The peptide composition of the present invention () is not absorbed incompletely like egg white protein (), does not have significant absorption antagonism between amino acids like an amino acid mixture (), and does not have low solubility. . Because of its better absorption than conventional protein digests (), the initial absorption rate values for each and total amount of amino acids are about 1.5 to 2.5 times higher. This difference in absorption rate is thought to be due to differences in absorption routes for amino acids and peptide compositions, whereas for egg white proteins it is thought to be due to a wide molecular weight distribution and a difference in absorption routes. It has been proven that the absorption rate is high because it is molecularized and the absorption antagonism between amino acids is small. As a result, as mentioned above, total nitrogen uptake increases and food efficiency increases.
It is thought that this not only improves weight gain (weight gain) but also lowers blood cholesterol levels. (2) Amino acid absorption is preferably close to the ideal amino acid administration pattern (), but in egg white protein () and amino acid mixtures (), the chi separation rate from the ideal absorption pattern () is particularly large for Phe-Tyr and His. On the contrary,
It was confirmed that the peptide composition of the present invention () is very close to the ideal absorption pattern () and achieves balanced amino acid absorption. The above test results clearly demonstrate that low-molecular-weight peptide compositions containing dipeptides and tripeptides as main components exhibit the various effects mentioned above and are extremely useful as nitrogen (protein) sources for nutritional supplements. It can be understood. Such a low-molecular-weight peptide composition is prepared by enzymatic hydrolysis using the entire arbitrary protein raw material as a nitrogen source, but the product cannot contain anything other than the amino acids of the starting raw material, and it is difficult to consider the starting raw material. There is nothing that has a better amino acid composition than egg white. Therefore, depending on the starting material, the amino acid composition of the obtained low molecular weight peptide composition may be out of balance compared to the ideal amino acid composition. In such a case, it is preferable to select starting materials or add necessary amino acids to the low-molecular-weight peptide composition used in the nutritional supplement of the present invention depending on the purpose of use. For example, depending on the starting material, the amino acid composition can be controlled as needed, such as using the necessary essential amino acids if the starting material is lacking in essential amino acids, or using that amino acid if the condition requires a specific amino acid. In addition, the present inventors set the content of free amino acids in the composition in order to take advantage of the high absorption rate of the peptide composition in nutritional physiology, or to keep it to a level that does not cause amino acid absorption antagonism. The upper limit is considered to be approximately 20wt%. The content of relatively large peptides with a molecular weight of 700 or more is preferably kept at 20 wt% or less so as not to reduce the initial absorption rate. Further, the average molecular weight is preferably a low molecular weight of 550 to 300. Various uses are possible for the nutritional supplement according to the present invention. It can also be used as a nutritional supplement to be administered orally or directly to the stomach or intestines, either as it is or mixed with other nutritional supplements. If flavor or preference is an issue, it can be used in combination with such additives. Taking advantage of its absorption specificity, which is different from that of proteins or amino acids, it becomes an ideal material for people with weak physical strength, people with poor physical strength, and infants. Food
It has high efficiency and lowers cholesterol levels, making it an effective nutritional material for people from middle age onwards. It can be used as a more efficient material for pre- and post-operative nutritional support than conventional amino acid mixtures or simply solubilized protein decomposition products.

Claims (1)

[Scope of Claims] 1. The main components are dipeptides and tripeptides with a molecular weight of 700 or more, a peptide content of 20 wt% or less, and a free amino acid content of 20 wt% or less, obtained by enzymatic hydrolysis using the whole protein raw material as a nitrogen source. A nutritional supplement comprising a low molecular weight peptide composition having an average molecular weight of 550 to 300. 2. The nutritional supplement according to claim 1, wherein the protein raw material is egg white.