CN-122011109-A - Quinoa hexapeptide with blood sugar reducing effect and application thereof

Abstract

The invention discloses quinoa hexapeptide with a blood sugar reducing effect and application thereof, and belongs to the technical field of bioactive peptides. The amino acid sequence of the quinoa hexapeptide PGSPGR is Pro-Gly-Ser-Pro-Gly-Arg, and the quinoa hexapeptide PGSPGR has alpha-glucosidase inhibitory activity and can effectively reduce blood sugar level, so that the quinoa hexapeptide can be applied to preparation of medicines or foods for reducing blood sugar. The invention also provides a polypeptide containing the peptide PGSPGR and quinoa peptide rich in the polypeptide, which are applied to the preparation of medicaments or foods for reducing blood sugar, provide a new scheme and theoretical basis for the treatment of diabetes, and have good market prospect and application potential.

Inventors

• YANG DAI
• ZHONG HAO
• YANG YU
• SHEN FEI
• WANG QIANQIAN

Assignees

• 浙江工业大学

Dates

Publication Date

20260512

Application Date

20260413

Claims (10)

1. 1. The quinoa hexapeptide is characterized in that the amino acid sequence of the quinoa hexapeptide is Pro-Gly-Ser-Pro-Gly-Arg.
2. 2. The quinoa hexapeptide according to claim 1, wherein the quinoa hexapeptide is prepared by a method comprising an enzymatic method, a solid-phase synthesis method or a genetic engineering method.
3. 3. The quinoa hexapeptide according to claim 1 or 2, wherein the quinoa hexapeptide has a hypoglycemic effect.
4. 4. A quinoa peptide with a hypoglycemic effect, wherein the quinoa peptide with a hypoglycemic effect comprises the quinoa hexapeptide as claimed in claim 1.
5. 5. A composition comprising, as a main ingredient, the composition comprises the quinoa hexapeptide of claim 1 or the quinoa peptide of claim 4.
6. 6. A product having a hypoglycemic effect, characterized in that it comprises a quinoa hexapeptide according to claim 1, a quinoa peptide according to claim 4 or a composition according to claim 5.
7. 7. The product according to claim 6, wherein the product is a drug for preventing or treating diabetes or a food for assisting in lowering blood sugar.
8. 8. The product of claim 7, wherein the diabetes is type 2 diabetes.
9. 9. The product of claim 6, further comprising a pharmaceutically acceptable carrier.
10. 10. Use of a quinoa hexapeptide according to claim 1, a quinoa peptide according to claim 4 or a composition according to claim 5 for the preparation of a hypoglycemic product.

Description

Quinoa hexapeptide with blood sugar reducing effect and application thereof Technical Field The invention belongs to the technical field of bioactive peptides, and particularly relates to quinoa hexapeptide with a blood sugar reducing effect and application thereof. Background Diabetes mellitus (Diabetes mellitus, DM) is a metabolic disease characterized mainly by chronic hyperglycemia, caused by defective insulin secretion and/or impaired biological action. Among them, type 2 diabetes mellitus (T2 DM) accounts for more than 90% of the total number of cases, and its core pathological mechanism involves insulin resistance and progressive decline of islet beta cell function. The persistent hyperglycemic state can cause a number of serious complications, such as cardiovascular disease, nephropathy, retinopathy and neuropathy, which place a heavy burden on the global public health system. At present, clinical hypoglycemic strategies are diverse, with α -glucoside inhibitors being one of the key targets for controlling postprandial blood glucose (PPBG). Alpha-glucosidase is located at the brush border of the small intestine and is a key digestive enzyme responsible for further breaking down oligosaccharides (e.g. maltose, sucrose) into absorbable monosaccharides (glucose) in the human body. By inhibiting the activity of alpha-glucosidase, the final digestion of carbohydrates and the absorption rate of glucose can be delayed, thereby effectively 'peak clipping and valley filling' and stabilizing postprandial blood glucose curve. Oral hypoglycemic agents such as metformin and miglitol and alpha-glucosidase inhibitors have been widely used clinically. However, these synthetic inhibitors often have side effects associated with flatulence, diarrhea, etc., affecting patient compliance. Therefore, the search for highly effective, low-toxic α -glucosidase inhibitors from natural sources has become an important direction in the development of functional foods and pharmaceuticals. Among the many natural sources, food-borne bioactive peptides are of great interest because of their high activity, low toxicity, good absorbability and biocompatibility. Numerous studies have demonstrated that specific peptide fragments released from soy, milk proteins, marine organisms and cereal proteins by enzymatic hydrolysis have significant alpha-glucosidase inhibitory activity. These peptide fragments bind to the active site of the enzyme via a specific amino acid sequence, achieving competitive or non-competitive inhibition. Wherein, quinoa is used as a super grain with comprehensive nutrition, and the protein has balanced amino acid composition and the characteristic of easy enzymolysis. The existing research shows that quinoa protein zymolyte and peptide fragments separated from quinoa protein zymolyte have various biological activities, wherein the biological activities comprise potential hypoglycemic effect, and the mechanism of the quinoa protein zymolyte can involve the inhibition of key digestive enzymes such as alpha-glucosidase and the like. The method provides a solid scientific basis for the directional development of novel alpha-glucosidase inhibitory peptides from quinoa proteins. Although the screening of active peptides from natural products is the mainstream strategy, the current research is focused on complex proteolytic substances or mixed peptide fragments, and the identification of key functional peptide fragments (especially the exact sequence acting on alpha-glucosidase) is insufficient, so that the activity of the product is unstable, the mechanism is not clear, and standardized application is difficult to realize. Therefore, the minimum active unit (such as hexapeptide) with definite alpha-glucosidase inhibitory activity is accurately identified, synthesized and verified from quinoa peptide, and the method has great significance in developing new generation of hypoglycemic functional components or pharmaceutical lead compounds with definite action targets and smaller side effects. The present invention is based on the above background and aims to overcome the deficiencies of the prior art. Disclosure of Invention Aiming at the problems, the invention aims to provide quinoa hexapeptide with blood sugar reducing effect and application thereof, wherein papain, neutral protease and flavourzyme are utilized to carry out biological enzymolysis on quinoa protein powder to obtain quinoa peptide, the LC-MS/MS peptide spectrum analysis technology is utilized to analyze the polypeptide sequence of the quinoa peptide, the quinoa peptide is found to be rich in PGSPGR peptide segments (the amino acid sequence is Pro-Gly-Ser-Pro-Gly-Arg), and quinoa hexapeptide PGSPGR has alpha-glucosidase inhibitory activity, can effectively reduce blood sugar level and has no obvious side effect, so that the quinoa hexapeptide can be applied to preparation of medicines or foods for reducing blood sugar. The technical scheme is that the amino