Intestinal health-care umami peptide from East China Sea large yellow croaker

Abstract

The invention discloses an intestinal health-care umami peptide derived from East China Sea pseudosciaena crocea, and discloses an umami peptide which is screened and separated from East China Sea pseudosciaena crocea and has an intestinal health-care function potential, and the umami peptide comprises at least one of small molecule peptides shown as SEQ ID 1-3, and the small peptides not only can be combined with an umami receptor T1R1 / T1R3, but also can be combined with a glutamine transporter ASCT2. Butt-joint energy results of flavor receptors are superior to that of sodium glutamate, disodium guanylate (IMP) monomers and disodium inosinate (GMP) monomers, and butt-joint energy results of glutamine transporters are superior to that of glutamine monomers, so that the polypeptides have certain development advantages when being used for preparing novel flavor enhancers. The small molecule peptide sequences SEQ ID 1-3 provided by the invention can be used for developing health-care foods or seasonings with the function of regulating intestines and stomach, the purposes of preventing, relieving and assisting in treating gastritis, enteritis, digestive tract mucosa injury and other symptoms are achieved through quantitative taking, and the small molecule peptide sequences SEQ ID 1-3 have wide market application prospects.

Description

Technical Field

[0001] The invention relates to the field of umami flavoring substances and gastrointestinal health care technology, in particular to intestinal health care umami peptides derived from large yellow croakers in the East China Sea. Background Art

[0002] Traditional single flavor enhancers, such as monosodium glutamate, have a lower flavor effect than compound flavor enhancers when used alone. Another example is the I+G (5'-flavor nucleotide disodium) potent flavor enhancer, which is a mixture of guanylic acid (IMP) and inosinic acid (GMP) in a 1:1 ratio. The overall performance of using multiple flavor enhancers together will be better. Small molecule umami peptides are an active substance with a structure between amino acids and proteins. They have low hyperosmotic effect, high bioavailability, strong flavoring ability, fast absorption rate, stable functional structure, and long retention time, which are more conducive to human absorption and utilization.

[0003] Umami peptides are widely distributed in natural foods, especially in aquatic products. Yellow croaker (Larimichthyscrocea), belonging to the order Perciformes, family Sciaenidae, genus Larimichthys, is known as "yellow croaker", "cucumber fish", "golden dragon", etc. It is a mid- and lower-layer migratory economic fish unique to the southeast coast of my country, and is also known as the "national fish". Yellow croaker meat is rich in nutrition and delicious. It contains relatively rich umami amino acids, such as aspartic acid, glutamic acid, glycine, alanine, and arginine. These amino acids and other umami flavoring substances give it a unique umami taste.

[0004] Umami peptides formed by enzymatic decomposition of proteins in yellow croaker meat have a broad market in the field of umami application. In addition, the rich and diverse small molecule peptides produced by enzymatic decomposition contain rich amino acid composition, and the proportions of various essential amino acids, non-essential amino acids, and conditionally essential amino acids in a peptide segment are different. The specific peptide sequences obtained after screening and separation provide the basis and possibility for the preparation of functional umami peptides, which provides the basis and guarantee for the development of umami peptide products with both umami taste and health care functions. Summary of the invention

[0005] The present invention uses bioinformatics analysis technology and computer processing to enzymatically hydrolyze large yellow croaker muscle protein, screens and identifies small molecule peptides obtained by enzymatic hydrolysis, and finally obtains small molecule bioactive peptides that can stably bind to umami receptors T1R1 / T1R3, and further screens and identifies active sites that can stably bind to glutamine transporter ASCT2 in the amino acid sequences of these active peptides, that is, these active peptides can smoothly pass through the specific transport on the cell membrane in vivo and enter the cell, thereby achieving the role of participating in energy metabolism, supporting continuous cell proliferation, and maintaining cell redox homeostasis. Especially in intestinal epithelial cells, a large number of research results have shown that glutamine can promote the thickening of intestinal mucosa, and artificial intake of glutamine is an effective treatment method for gastrointestinal digestive tract conditioning.

[0006] Therefore, based on the above perspective, the present invention uses the amino acid sequence of large yellow croaker after enzymatic hydrolysis to develop a variety of small molecule functional umami peptide sequences that can stably bind to the umami receptor T1R1 / T1R3 and the glutamine transporter ASCT2 at the same time, providing new ideas and references for the preparation of health-care umami peptides.

[0007] In order to achieve the above object, the present invention provides the following technical solutions: The intestinal health umami peptide derived from large yellow croaker in the East China Sea, the peptide is derived from large yellow croaker actin, can not only bind to the umami receptor T1R1 / T1R3, but also bind to the glutamine transporter ASCT2, including at least one of the following small molecule peptides: The amino acid sequence is QDE, SEQ ID NO.1; The amino acid sequence is QMEDDR, SEQ ID NO.2; The amino acid sequence is QDEEMGQK, SEQ ID NO.3.

[0008] Preferably, the polypeptide is derived from large yellow croaker actin, and comprises the peptide sequence with the T1R1 binding site as the core; Among them, the amino acid sequence is QDE, and the amino acid residues of the polypeptide of SEQ ID NO. 1 and the T1R1 binding site are PRO413, PRO123, LYS412, ASP147, ASP415, SER94, and LYS418; The amino acid sequence is QMEDDR, and the amino acid residues of the polypeptide of SEQ ID NO. 2 and the T1R1 binding site are LYS418, ASP147, PRO413, ILE414, ASP93, LYS121, and GLU101; The amino acid sequence is QDEEMGQK, and the amino acid residues of the polypeptide of SEQ ID NO. 3 and the T1R1 binding site are MET411, LYS412, ILE124, SER94, and GLU83.

[0009] Preferably, the polypeptide is derived from large yellow croaker actin, and comprises the peptide sequence with the T1R3 binding site as the core; Wherein, the amino acid sequence is QMEDDR, and the amino acid residues of the polypeptide of SEQ ID NO. 2 and the T1R3 binding site are VAL89, SER92, LEU371, GLY373, TYR101, LYS369; The amino acid sequence is QDEEMGQK, and the amino acid residues of the polypeptide of SEQ ID NO. 3 and the T1R3 binding site are ASP372, LYS34, THR94, GLN141, SER92, GLY13, GLU12, LEU371, TYR101, ALA99, LYS369, and LEU117.

[0010] Preferably, the polypeptide is derived from large yellow croaker actin, and includes the peptide sequence with the ASCT2 binding site as the core; Among them, the amino acid sequence is QDE, and the amino acid residues of the polypeptide of SEQ ID NO. 1 and the ASCT2 binding site are LYS288, ARG465, ARG101, and PRO432; The amino acid sequence is QMEDDR, and the amino acid residues of the polypeptide of SEQ ID NO. 2 and the ASCT2 binding site are GLU291, ARG101, LYS288, ARG465, and ALA433; The amino acid sequence is QDEEMGQK, and the amino acid residues of the polypeptide of SEQ ID NO. 3 and the ASCT2 binding site are PRO432, ASP460, ARG101, ARG465, LYS288, and LEU457.

[0011] Preferably, the docking energy of any one of the small molecule peptides from SEQ ID NO.1 to SEQ ID NO.3 with the T1R1 umami taste receptor is less than -58 kcal / mol, the interaction energy is less than -54 kcal / mol, the electrostatic energy is less than -247 kcal / mol, and the van der Waals force is less than -5 kcal / mol.

[0012] Preferably, the docking energy of any one of the small molecule peptides from SEQ ID NO.2 to SEQ ID NO.3 with the T1R3 umami taste receptor is less than -106 kcal / mol, the interaction energy is less than -75 kcal / mol, the electrostatic energy is less than -476 kcal / mol, and the van der Waals force is less than -14 kcal / mol.

[0013] Preferably, the docking energy of any one of the small molecule peptides in SEQ ID NO.1 to SEQ ID NO.3 and the ASCT2 glutamine transporter is less than -89 kcal / mol, the interaction energy is less than -60 kcal / mol, the electrostatic energy is less than -247 kcal / mol, and the van der Waals force is less than -3 kcal / mol.

[0014] In the above technical scheme, the intestinal health umami peptides from large yellow croaker from the East China Sea provided by the present invention, (1) the polypeptide is from large yellow croaker actin, the amino acid sequence is QDE, QMEDDR, QDEEMGQK, the docking energies of these three polypeptides with the umami receptor T1R1 are -79.1557kcal / mol, -58.0305kcal / mol, -149.801kcal / mol, respectively, while the docking energy of sodium glutamate with T1R1 is -57.8901kcal / mol. The lower the docking energy, the easier it is to bind. Therefore, these three polypeptides are easier to bind to the umami receptor T1R1 than sodium glutamate, and are a variety of effective new umami peptides; (2) The peptides are from large yellow croaker actin, with amino acid sequences of QMEDDR and QDEEMGQK. The docking energies of these two peptides with the umami receptor T1R3 are -126.083 kcal / mol and -106.084 kcal / mol, respectively, while the docking energy of sodium glutamate with T1R3 is -46.719 kcal / mol. The lower the docking energy, the easier it is to bind. These two peptides are more likely to bind to the umami receptor T1R3 than sodium glutamate, and are a variety of effective new umami peptides. (3) The peptides are from large yellow croaker actin, and the amino acid sequences are QDE, QMEDDR, and QDEEMGQK. The docking energies of these three peptides with the glutamine transporter ASCT2 are -89.5434 kcal / mol, -124.667 kcal / mol, and -152.029 kcal / mol, respectively, while the docking energy of glutamine monomer with ASCT2 is -40.9244 kcal / mol. The lower the docking energy, the easier it is to bind. These three peptides are easier to bind to the transporter ASCT2 than glutamine. They are a variety of umami peptides with glutamine intestinal regulatory function.

[0015] (4) The present invention discloses umami peptides with potential in intestinal health care function screened and separated from East China Sea large yellow croaker, including at least one of the small molecule peptides of SEQ ID 1 to 3. These small peptides can not only bind to umami receptors T1R1 / T1R3, but also bind to glutamine transporter ASCT2. The umami receptor docking energy results are better than those of monosodium glutamate, disodium guanylate (IMP) monomer, and disodium inosinate (GMP) monomer. The glutamine transporter docking energy results are better than those of glutamine monomer. Therefore, there is a certain development advantage in using these peptides to prepare new umami agents.

[0016] (5) The small molecule peptide sequences of SEQ ID 1 to 3 provided by the present invention can be used to develop health foods or condiments with gastrointestinal function regulation. By taking a fixed amount, the purpose of preventing, alleviating and assisting in the treatment of symptoms such as gastritis, enteritis and digestive tract mucosal damage can be achieved, and the market application prospects are broad. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is the homology modeling diagram of umami taste receptor T1R1, a1, a2, and a3 are the model structure diagram, normalized result diagram, and model Laplace diagram of T1R1 respectively; Figure 2 is the homology modeling diagram of umami receptor T1R3, b1, b2, and b3 are the model structure diagram, normalized result diagram, and model Laplace diagram of T1R3 respectively; Figure 3 It is the homology modeling of glutamine transporter ASCT2. c1, c2, and c3 are the model structure diagram, normalized result diagram, and model Ramachandran diagram of ASCT2, respectively. Figure 4 These are the molecular docking diagrams of the peptide with the amino acid sequence QDE and the umami taste receptor T1R1; among them, A1, A2, and A3 are the three-dimensional binding diagram, detail magnification diagram, and 2D interaction diagram corresponding to the docking of QDE and T1R1 receptor; Figure 5 , Figure 6 It is the molecular docking diagram of the peptide with amino acid sequence QMEDDR and umami taste receptors T1R1 and T1R3 respectively; Figure 5 In the figure, B1, B2, and B3 are the three-dimensional binding map, detail magnification map, and 2D interaction map corresponding to the docking of QMEDDR with T1R1 receptor; Figure 6In the figure, C1, C2, and C3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QMEDDR with the T1R3 receptor; Figure 7 , Figure 8 It is the molecular docking diagram of the peptide with amino acid sequence QDEEMGQK and umami taste receptors T1R1 and T1R3 respectively; Figure 7 In the figure, D1, D2, and D3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDEEMGQK with the T1R1 receptor; Figure 8 In the figure, E1, E2, and E3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDEEMGQK with the T1R3 receptor; Fig. 9 , Fig.10 , Fig.11 It is the molecular docking diagram of three peptides and glutamine transporter ASCT2; Fig. 9 In the figure, F1, F2, and F3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDE with the ASCT2 transporter; Fig.10 In the figure, G1, G2, and G3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QMEDDR and ASCT2 transporter; Fig.11 In the figure, H1, H2, and H3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDEEMGQK with the ASCT2 transporter; Fig.12 This is the energy-minimized structure diagram of the functional peptide Gin-Asp-Glu with the amino acid sequence of QDE; Fig.13 This is the energy-minimized structure diagram of the functional small peptide Gin-Met-Glu-Asp-Asp-Arg with the amino acid sequence of QMEDDR; Fig.14 This is the energy-minimized structure diagram of the functional peptide Gin-Asp-Glu-Glu-Met-Gly-Gin-Lys with the amino acid sequence QDEEMGQK; Fig.15 It is the energy-minimized binding diagram of the functional small peptides with the amino acid sequences of QDE, QMEDDR, and QDEEMGQK. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0020] The present invention will be further described below in the form of specific embodiments.

[0021] Example 1 Homology Modeling of Umami Taste Receptor T1R1 The T1R1 receptor sequence used is: SSQRSVARMDGDVIIGALFSVHHQPPAEKVPERKCGEIREQYGIQRVEAMFHTLDKINADPVLLPNITLGSEIRDSCWHSSVALEQSIEFIRDSLISIRDEKDGLNRCLPDGQTL PPGRTKKPIAGVIGPGSSSVAIQVQNLLQLFDIPQIAYSATSIDLSDKTLYKYFLRVVPSDTLQARAMLDIVKRYNWTYVSAVHTEGNYGEKSFDRLLRKLRERLPKARVVVCFC EGMTVRGLLSAMRRLGVVGEFSLIGSDGWADRDEVIEGYEVEANGGITIKLQSPEVRSFDDYFLKLRLDTNTRNPWFPEFWQHRFQCRLPGHLLENPNFKKVCTGNESLEENYVQ DSKMGFVINAIYAMAHGLQNMHHALCPGHVGLCDAMKPIDGRKLLDFLIKSSFVGVSGEEVWFDEKGDAPGRYDIMNLQYTEANRYDYVHVGTWHEGVLNIDDYKIQMNKSGMVRS The model structure diagram, normalized result diagram, and model Ramachandran diagram of T1R1 receptor protein are shown in Figure 1 As shown in a1, a2, and a3, the quality evaluation results of the T1R1 receptor protein structure model are shown in Table 1. The results in the comprehensive chart show that the model is reasonable and reliable.

[0022] Example 2 Homology Modeling of Umami Taste Receptor T1R3 The T1R3 receptor sequence used was: DHNFMRREIKIEGDLVLGGLFPINEKGTGTEECGRINEDRGIQRLEAMLFAIDEINKDNYLLPGVKLGVHILDTCSRDTYALEQSLEFVRASLTKVDEAEYMCPDGSYAIQENIPLLIAGVIGGSYSSVSIQVANLLR LFQIPQISYASTSAKLSDKSRYDYFARTVPPDFYQAKAMAEILPFFNWTYVSTVASEGDYGETGIEAFEQEARLRNICIATAEKVGRSNIRKSYDSVIRELLQKPNARVVVLFMRSDDSRELIAAANRVNASFTWVASD GWGAQESIVKGSEHVAYGAITLELASHPVRQFDRYFQSLNPYNNHRNPWFRDFWEQKFQCSLQNKRNHRQVCDKHLAIDSSNYEQESKIMFVVNAVYAMAHALHKMQRTLVPQTTKLCDAMKILDGKKLYKEYLLKIQF TAPFNPNKGADSIVKFDTFGDGMGRYNVFNLQQTGGKYSYLKVGHWAETLSLDVDSIHWSRNSVPTSQCSDPCAPNEMKNMQPGDVCCWICIPCEPYEYLVDEFTCMDCCGPGQWPTADLSGCYNLPEDYIKWEDALVPR The model structure diagram, normalized result diagram, and model Ramachandran diagram of T1R3 receptor protein are shown in Figure 1. Figure 2 As shown in b1, b2, and b3, the quality evaluation results of the T1R3 receptor protein structure model are shown in Table 2. The results in the comprehensive chart show that the model is reasonable and reliable.

[0023] Example 3 Homology Modeling of Umami Taste Receptor ASCT2 The ASCT2 receptor sequence used was: MVADPPRDSKGLAAAEPTANGGLALASIEDQGAAAGGYCGSRDQVRRCLRANLLVLLTVVAVVAGVALGLGVSGAGGALALGPERLSAFVFPGELLLRLLRMIILPLVVCSLIGGAASLDPGALGRLGAWALLFF LVTTLLASALGVGLALALQPGAASAAINASVGAAGSAENAPSKEVLDSFLDLARNIFPSNLVSAAFRSYSTTYEERNITGTRVKVPVGQEVEGMNILGLVVFAIVFGVALRKLGPEGELLIRFFNSFNEATMVLV SWIMWYAPVGIMFLVAGKIVEMEDVGLLFARLGKYILCCLLGHAIHGLLVLPLIYFLFTRKNPYRFLWGIVTPLATAFGTSSSSATLPLMMKCVEENNGVAKHISRFILPIGATVNMDGAALFQCVAAVFIAQLS QQSLDFVKIITILVTATASSVGAAGIPAGGVLTLAIILEAVNLPVDHISLILAVDWLVDRSCTVLNVEGDALGAGLLQNYVDRTESRSTEPELIQVKSELPLDPLPVPTEEGNPLLKHYRGPAGDATVASEKESVM The ASCT2 receptor protein model structure diagram, normalized result diagram, and model Ramachandran diagram are shown in Figure 2. Figure 3 As shown in c1, c2, and c3, the quality evaluation results of the ASCT2 receptor protein structure model are shown in Table 3. The results in the comprehensive chart show that the model is reasonable and reliable.

[0024] Example 4 Large yellow croaker actin enzymatic hydrolysis results The large yellow croaker actin fragment is, with a total number of sites of 2014: The large yellow croaker protein with known amino acid sequence was enzymatically hydrolyzed using trypsin, the reaction pH range was 2<pH<5, and the enzymatic hydrolysis temperature T range was 20℃<T<45℃; among them, a variety of yellow croaker small peptides including three polypeptides with amino acid sequences of QDE, QMEDDR, and QDEEMGQK were obtained.

[0025] When the enzyme used is pepsin, the reaction pH range is 2<pH<5, and the enzymatic hydrolysis temperature T range is 20℃<T<45℃, a variety of yellow croaker small peptides including the three polypeptides with amino acid sequences of QDE, QMEDDR, and QDEEMGQK are not obtained.

[0026] When the enzyme used is proteinase K, the reaction pH range is 2<pH<5, and the enzymatic hydrolysis temperature T range is 20℃<T<45℃, a variety of yellow croaker small peptides including the three polypeptides with amino acid sequences of QDE, QMEDDR, and QDEEMGQK are not obtained.

[0027] Therefore, the large yellow croaker protein with known amino acid sequence was enzymatically hydrolyzed to obtain the three functional polypeptides QDE, QMEDDR, and QDEEMGQK. Trypsin treatment was the best treatment method in the present invention.

[0028] The specific action sites of trypsin, pepsin and proteinase K are shown in Table 4.

[0029] Example 5 Docking of peptides with umami taste receptors The three yellow croaker peptides QDE, QMEDDR and QDEEMGQK obtained by enzymatic hydrolysis were molecularly docked with the umami receptors T1R1 / T1R3 respectively.

[0030] Molecular docking of QDE and umami taste receptor T1R1 Figure 4 As shown; A1, A2, and A3 are the three-dimensional binding diagram, detail magnification diagram, and 2D interaction diagram corresponding to the docking of QDE and T1R1 receptor; The molecular docking of QMEDDR with umami taste receptors T1R1 and T1R3 are shown in Figure 2 Figure 5 , Figure 6 As shown; Figure 5 In the figure, B1, B2, and B3 are the three-dimensional binding map, detail magnification map, and 2D interaction map corresponding to the docking of QMEDDR with T1R1 receptor; Figure 6 In the figure, C1, C2, and C3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QMEDDR with the T1R3 receptor; The molecular docking of QDEEMGQK with umami taste receptors T1R1 and T1R3 are shown in Figure 7 , Figure 8 As shown; Figure 7 In the figure, D1, D2, and D3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDEEMGQK with the T1R1 receptor; Figure 8 In the figure, E1, E2, and E3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDEEMGQK with the T1R3 receptor; Monosodium glutamate monomer, disodium inosinate (IMP) monomer, and disodium guanylate (GMP) monomer were docked using the same molecular docking method as the above-mentioned polypeptides as three groups of comparative references.

[0031] The molecular docking energy is detailed in Tables 5 and 6.

[0032] The factors affecting the docking effect of small molecules with umami receptors include interaction energy, hydrogen bond energy, electrostatic energy, and van der Waals force. It can be seen from Tables 5 and 6 that the docking energies of QDE, QMEDDR, QDEEMGQK with T1R1 and T1R3 are all lower than those of sodium glutamate. The lower the required docking energy, the better the docking effect. Therefore, the above three umami peptides obtained from large yellow croaker have better effects.

[0033] Example 6 Docking of polypeptides with glutamine transporter The three yellow croaker peptides QDE, QMEDDR and QDEEMGQK obtained by enzymatic hydrolysis were molecularly docked with the glutamine transporter ASCT2.

[0034] The molecular docking of the three peptides with the glutamine transporter ASCT2 is shown in the figure below. Fig. 9 , Fig.10 , Fig.11 As shown; Fig. 9 In the figure, F1, F2, and F3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDE with the ASCT2 transporter; Fig.10 In the figure, G1, G2, and G3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QMEDDR and ASCT2 transporter; Fig.11 In the figure, H1, H2, and H3 are the three-dimensional binding map, detailed magnified map, and 2D interaction map corresponding to the docking of QDEEMGQK with the ASCT2 transporter; Glutamine was used as a comparative reference using the same molecular docking method as the above-mentioned peptides.

[0035] The molecular docking energy is detailed in Table 7.

[0036] The factors that affect the successful binding and transport of small molecules by glutamine include interaction energy, hydrogen bond energy, electrostatic energy, and van der Waals force. As can be seen from Table 7, the docking energies of QDE, QMEDDR, QDEEMGQK with the glutamine transporter ASCT2 are all lower than those of glutamine monomers. The lower the required docking energy, the better the docking effect. Therefore, the above three functional peptides obtained from large yellow croaker have better effects.

[0037] Example 7 Display of polypeptide molecular structure The functional peptide with the amino acid sequence QDE is Gin-Asp-Glu, and its structure after energy minimization is as follows Fig.12 shown.

[0038] The functional peptide with the amino acid sequence QMEDDR is Gin-Met-Glu-Asp-Asp-Arg, and its energy-minimized structure is as follows Fig.13 shown.

[0039] The functional peptide with the amino acid sequence QDEEMGQK is Gin-Asp-Glu-Glu-Met-Gly-Gin-Lys, and its energy-minimized structure is as follows Fig.14 shown.

[0040] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An intestinal health umami peptide derived from large yellow croaker from the East China Sea, characterized in that: The polypeptide is derived from large yellow croaker actin, and can not only bind to the umami receptor T1R1 / T1R3, but also bind to the glutamine transporter ASCT2, and includes at least one of the following small molecule peptides: The amino acid sequence is QDE, SEQ ID NO.1; The amino acid sequence is QMEDDR, SEQ ID NO.2; The amino acid sequence is QDEEMGQK, SEQ ID NO.

3.

2. The intestinal health umami peptide derived from large yellow croaker from the East China Sea according to claim 1, characterized in that: The polypeptide is derived from large yellow croaker actin, and includes a peptide sequence with the T1R1 binding site as a core; Among them, the amino acid sequence is QDE, and the amino acid residues of the polypeptide of SEQ ID NO. 1 and the T1R1 binding site are PRO413, PRO123, LYS412, ASP147, ASP415, SER94, and LYS418; The amino acid sequence is QMEDDR, and the amino acid residues of the polypeptide of SEQ ID NO. 2 and the T1R1 binding site are LYS418, ASP147, PRO413, ILE414, ASP93, LYS121, and GLU101; The amino acid sequence is QDEEMGQK, and the amino acid residues of the polypeptide of SEQ ID NO. 3 and the T1R1 binding site are MET411, LYS412, ILE124, SER94, and GLU83.

3. The intestinal health umami peptide derived from East China Sea large yellow croaker according to claim 1, characterized in that: The polypeptide is derived from large yellow croaker actin, and includes the peptide sequence with the T1R3 binding site as the core; Wherein, the amino acid sequence is QMEDDR, and the amino acid residues of the polypeptide of SEQ ID NO. 2 and the T1R3 binding site are VAL89, SER92, LEU371, GLY373, TYR101, LYS369; The amino acid sequence is QDEEMGQK, and the amino acid residues of the polypeptide of SEQ ID NO. 3 and the T1R3 binding site are ASP372, LYS34, THR94, GLN141, SER92, GLY13, GLU12, LEU371, TYR101, ALA99, LYS369, and LEU117.

4. The intestinal health umami peptide derived from East China Sea large yellow croaker according to claim 1, characterized in that: The polypeptide is derived from large yellow croaker actin, and includes a peptide sequence with the ASCT2 binding site as a core; Among them, the amino acid sequence is QDE, and the amino acid residues of the polypeptide of SEQ ID NO. 1 and the ASCT2 binding site are LYS288, ARG465, ARG101, and PRO432; The amino acid sequence is QMEDDR, and the amino acid residues of the polypeptide of SEQ ID NO. 2 and the ASCT2 binding site are GLU291, ARG101, LYS288, ARG465, and ALA433; The amino acid sequence is QDEEMGQK, and the amino acid residues of the polypeptide of SEQ ID NO. 3 and the ASCT2 binding site are PRO432, ASP460, ARG101, ARG465, LYS288, and LEU457.

5. The intestinal health umami peptide derived from large yellow croaker from the East China Sea according to claim 2, characterized in that: The docking energy of any one of the small molecule peptides from SEQ ID NO.1 to SEQ ID NO.3 with the T1R1 umami taste receptor is less than -58 kcal / mol, the interaction energy is less than -54 kcal / mol, the electrostatic energy is less than -247 kcal / mol, and the van der Waals force is less than -5 kcal / mol.

6. The intestinal health umami peptide derived from large yellow croaker from the East China Sea according to claim 3, characterized in that: The docking energy of any one of the small molecule peptides from SEQ ID NO.2 to SEQ ID NO.3 with the T1R3 umami taste receptor is less than -106 kcal / mol, the interaction energy is less than -75 kcal / mol, the electrostatic energy is less than -476 kcal / mol, and the van der Waals force is less than -14 kcal / mol.

7. The intestinal health umami peptide derived from East China Sea large yellow croaker according to claim 4, characterized in that: The docking energy of any one of the small molecule peptides from SEQ ID NO.1 to SEQ ID NO.3 and the ASCT2 glutamine transporter is less than -89 kcal / mol, the interaction energy is less than -60 kcal / mol, the electrostatic energy is less than -247 kcal / mol, and the van der Waals force is less than -3 kcal / mol.

8. The intestinal health umami peptide derived from East China Sea large yellow croaker according to claim 1, characterized in that: The following steps are involved: S1. The amino acid sequence of the large yellow croaker protein fragment is known; S2. The large yellow croaker protein with known amino acid sequence is enzymatically hydrolyzed, the enzyme used is trypsin, the reaction pH range is 2<pH<5, the enzymatic hydrolysis temperature T range is 20℃<T<45℃, and functional umami peptides are obtained after enzymatic hydrolysis.

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