APPLICATION OF A GLUTAMINE DERIVATIVE IN THE PREPARATION OF ANIMAL FEED ADDITIVES

Abstract

The present invention provides for the use of a glutamine derivative in the preparation of animal feed additives and, in particular, the use of a glutamine derivative having a structure of Formula (I), a racemate thereof, a stereoisomer thereof, a geometric isomer thereof, a tautomer thereof, a solvate thereof, or a salt thereof acceptable for use in feed. Experiments in animal husbandry have revealed that the provided compounds, including the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, and the salt thereof acceptable for use in feed, can be used as animal feed additives, exhibiting an excellent effect in improving animal performance, such as growth and feed efficiency. (See Formula I).

Description

APPLICATION OF A GLUTAMINE DERIVATIVE IN THE PREPARATION OF ANIMAL FEED ADDITIVES TECHNICAL FIELD The present invention relates to the field of animal feed additives and, in particular, relates to the use of a glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or a salt thereof acceptable for use in food, in the preparation of animal feed additives; the present invention also relates to a feed composition containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in food, and further relates to the use of the feed composition in the preparation of animal feed additives or animal feed per se. BACKGROUND OF THE INVENTION Generally, amino-acylated glutamine derivatives are intermediates in the production of amide-substituted glutamine derivatives. The reaction of N-acetyl-DL-theanine with the aminoacylase from Aspergillus oryzae to obtain L-theanine under suitable conditions has been reported. The reaction of L-glutamic acid with italic anhydride to obtain phthaloyl-L-glutamic acid, which is subsequently converted to an acid anhydride, has also been reported. The acid anhydride is then subjected to ammonolysis in an aqueous ethylamine solution to obtain phthaloyl-L-theanine, and subsequently, L-theanine is obtained by removing the phthaloyl group from phthaloyl-L-theanine in the presence of hydrazine hydrate. Amino-acylated derivatives of glutamine can synergistically enhance sensory performance. Aqueous solutions of N-acyl-theanine have been reported to have a disappointingly weak fatty taste, but it is possible to complement, enhance, or strengthen both the basic or actual fragrance and the flavor of foods / beverages by combining this compound with flavoring agents and carefully adjusting their levels. Food additives refer to substances added in small or trace amounts during food processing, production, and application. These include both nutritive food additives and general food additives. General food additives are substances added to food in small or trace amounts to ensure and improve food quality and increase its utilization. Currently, commonly used general food additives can increase [amount missing] from [amount missing]. N c The use of feed additives that aim to make feed utilization both efficient and stable, as well as improve animal productivity, primarily includes high-copper agents, high-zinc agents, antibiotics formulated into feed, and chemically synthesized antibacterial agents. However, the long-term use of these substances in animal husbandry can lead to significant side effects, such as liver and kidney toxicity, growth inhibition, kidney damage, urinary tract disorders, teratogenesis, mutagenesis, drug resistance, drug residues, and environmental contamination. To ensure animal health and improve the productive efficiency of animal husbandry, developing novel feed additives that are effective, stable, and safe is an urgent necessity. SUMMARY OF THE INVENTION In view of the foregoing, the present invention provides the use of: a glutamine derivative, a racemate thereof, a stereoisomer thereof, a geometric isomer thereof, a tautomer thereof, a solvate thereof, or a salt thereof acceptable for use in food, in the preparation of animal feed additives; the present invention also provides a food composition containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, and further provides the use of the food composition in the preparation of animal feed additives or animal feed per se. In one aspect, the present invention provides a glutamine derivative having a structure of formula (I), a racemate thereof, a stereoisomer thereof, a geometric isomer thereof, a tautomer thereof, a solvate thereof, or a salt thereof acceptable for use in food. Formula (I) In some technical solutions, Y is an OC1-C20 alkyl group or an OH; X is a C4-C10 cycloalkyl group containing nitrogen, an NHC1-C20 alkyl group, or an N(Ci-C2o)2 alkyl group; R1 is R1aC(=O), R1bC(=O), R1aS(=O)2, R1bS(=O)2, or H; R2 is R2aC(=O), R2bC(=O), R2aS(=O)2, or R2bS(=O)2; each of R1 and R2 is, independently, a C1-C20 alkyl group, a C3-C7 cycloalkyl group, or either a C1-C20 alkyl group or a C3-C7 cycloalkyl group that is optionally substituted with one, two, three, four, or five R3s; where said R3 is a: -OH, -NH2, -CN, -SH, or -X1, where X1 is selected from: F, Cl, Br, or I;each of R1ay R2a is, independently, a C5-C12 aryl group, a C5-C12 heteroaryl group, a C5-C12 -(C1-C4 alkylidene)-aryl group, a C5-C12 -(C1-C4 alkylidene)heteroaryl group, or either a C5-C12 aryl group, a C5-C12 heteroaryl group, a C5-C12 (C1-C4 alkylidene)-aryl group, or a C5-C12 -(C1-C4 alkylidene)-heteroaryl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1C5 alkyl group substituted with X2, wherein the X2 is selected from: F, Cl, Br, or I.; In some technical solutions, R1 is R1aC(=O) or H; R2 is R2aC(=O); each of R1a and R2a is, independently, a C5-C12 aryl group, a C5-C12 heteroaryl group, a C5-C12 -(C4-alkylidene)aryl group, a C5-C12 -(C4-alkylidene)heteroaryl group, or either a C5-C12 aryl group, a C5-C12 heteroaryl group, a C5-C12 -(C4-alkylidene)aryl group, or a C5-C12 -(C4-alkylidene)heteroaryl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, C1-C5 alkoxy group, C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. In some technical solutions, R1 is an H; R2 is an R2aC(=O); R2a is a C5-C12 aryl group, a C5-C12 -(C4-alkylidene)-aryl group, or either a C5-C12 aryl group or a C5-C12 -(C4-alkylidene)-aryl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. In some technical solutions, R1 is H; R2 is an R2aC(=O); R2a is an aryl group Ce, a -(C4-alkylidene)-aryl group Ce, or either an aryl group Ce or a -(C4-alkylidene)-aryl group Ce, which is optionally substituted with one, two, three, four, or five R4; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. In some technical solutions, R2a is a phenyl group, a -(C1C4 alkylidene)phenyl group, or a phenyl group or a -(C1-C4 alkylidene)phenyl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. In some technical solutions, R1 is an H; R2 is an R2aC(=O); R2a is a phenyl group or a phenyl group that is replaced by an R4; where said R4 is a: -OH, -NH2, -NO2, H+can / iznz / q / Yi -CN, -SH, -X2, a C1-C5 alkoxy group, or a C1-C5 alkyl group, wherein X2 is selected from: F, Cl, Br, or I; R2 is a C1-C15 alkyl group; Y is an -OH or an -OC1-C5 (an alkoxy group having 1 to 5 carbon atoms); X is an -NHC1-C5 (an alkylamino group which in turn has a C1-C5 alkyl group). In some technical solutions, R1 is R1bC(=O) or H; R2 is R2bC(=O); each of R1 and R2 is, independently, a C1-C20 alkyl group, a C3-C6 cycloalkyl group, or either a C1-C20 alkyl group or a C3-C7 cycloalkyl group that is optionally substituted with one, two, three, four, or five R3; wherein said R3 is a: -OH, -NH2, -CN, -SH, or -X1, wherein X1 is selected from: F, Cl, Br, or I. In some technical solutions, R1 is either an H; R2 is an R2bC(=O); R2 is a C1-C20 alkyl group or is a C1-C20 alkyl group that is optionally replaced with one, two, three, four, or five R3; wherein said R3 is a: -OH, -NH2, -CN, -SH or -X1, wherein X1 is selected from: F, Cl, Br, or I. In some technical solutions, Y is an OC1-C10 alkyl group. In some technical solutions, X is a nitrogen-containing C4-C10 cyclo-alkyl group. In some technical solutions, X is an NHC1-C20 alkyl group. In some technical solutions, X is preferably an NHcr C10 alkyl group. In another aspect, the present invention provides the use of the above-mentioned glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in food, in the preparation of an animal feed additive. In another aspect, the present invention provides a food composition containing at least one of the glutamine derivatives provided herein, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, and the salt thereof acceptable for use in food, and a food adjuvant suitable for the food, wherein said adjuvant is selected from: a vehicle, a diluent, a solvent, an excipient, or a combination thereof. In some technical solutions, the food composition also contains a raw material for animal feed. In some technical solutions, the food composition also contains an additional additive for animal feed. bbcan / i znz / zi / Yl· In some technical solutions, the feed composition also contains an animal feed ingredient and an additional animal feed additive. In some technical solutions, the additional animal feed additive is selected from among a nutritive feed additive and / or a general feed additive and / or a medicinal feed additive. In another aspect, the present invention provides for the use of the food composition in order to prepare an additive for animal feed. In another aspect, the present invention provides for the use of the food composition for the purpose of preparing animal feed. In another aspect, the present invention also provides a method for improving the productive performance of farm animals. Beneficial effects of the present invention: Experiments in animal breeding show that the described compounds, including the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, and the salt thereof acceptable for use in food, can be used as additives for animal feed and have an excellent effect on improving the productive performance of animals, such as growth and feed efficiency. Any embodiment of any aspect of the present invention may be combined with other embodiments provided there is no contradiction between them. Furthermore, any technical feature in any embodiment of any aspect of the present invention may be applied as the same technical feature in other embodiments, provided there is no contradiction between them. The foregoing content only provides a general overview of certain aspects of the present invention, which is not limited to these aspects. The content involved, both above and in other aspects, will be described in greater detail and more comprehensively later. A more detailed description of the present invention is provided below. In this document, certain embodiments of the present invention will be described in greater detail, examples of which are illustrated by the accompanying structural and chemical formulas. The intention of the present invention is to cover all substituted, modified, and equivalent technical solutions, all of which fall within the scope of the present invention as defined in the claims. Furthermore, certain technical features of the present invention I bbCQn / l 7O7 / 3 / YL invention, and for the purpose of being clearly presented, they may be described separately in multiple independent modalities; however, these may also be provided in a single modality either in combination or in any suitable sub-combination. Compound The compound involved in the present invention is a glutamine derivative having a structure of formula (I). bbcan / i znz / zi / Yl· Formula (I) Where Y is a substituent on the oxygen atom (abbreviated O) where the active hydrogen atom in the carboxyl group of the glutamine derivative has been substituted. X is a group resulting from the substitution of the amide group of the glutamine derivative on the nitrogen atom of the amino group (abbreviated N). R1 ​​and R2 are substituents of the amino group on the nitrogen atom (abbreviated N). Furthermore, Y is an OC1-C20 alkyl group or an OH; X is a nitrogen-containing C4Cw cycloalkyl group, an NHC1-C20 alkyl group, or an N(Ci-C2o)2 alkyl group; R1 is an R1aC(=O), an R1bC(=O), an R1aS(=O)2, an R1bS(=O)2, or an H; R2 is an R2aC(=O), an R2bC(=O), an R2aS(=O)2, or an R2bS(=O)2. Each of R1 and R2 is, independently, a C1-C20 alkyl group or a C3-C7 cycloalkyl group, whether substituted or unsubstituted, where R1 and / or R2 is a substituted C1-C20 alkyl group or C3-C7 cycloalkyl group, the C1-C20 alkyl group or C3-C7 cycloalkyl group is a C1-C20 alkyl group or a C3-C7 cycloalkyl group that is optionally substituted with one, two, three, four, or five R3s; wherein said R3 is a: -OH, -NH2, -CN, -SH, or -Xi, wherein X1 is selected from: F, Cl, Br, or I. Each of R1 and R2a is, independently, a C5-C12 aryl group, a C5-C12 heteroaryl group, a C5-C12 -(C1-C4 alkylidene)-aryl group, or a C5-C12 -(C1-C4 alkylidene)heteroaryl group, whether substituted or unsubstituted, when R1 or R2a is a substituted C5-C12 aryl group, a C5-C12 heteroaryl group, a C5-C12 -(C1-C4 alkylidene)-aryl group, or a substituted C5-C12 -(C1-C4 alkylidene)-heteroaryl group, the C5-C12 aryl group, the C5-C12 heteroaryl group, the C5-C12 (C1-C4 alkylidene)-aryl group, or the C5-C12 -(C1-C4 alkylidene)-heteroaryl group. is a C5-C12 aryl group, a C5-C12 heteroaryl group, a C5-C12 -(C4-alkylidene)-ahlo group, or a C5-C12 (C4-alkylidene)-heteroahlo group that is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein the X2 is selected from: F, Cl, Br, or I. Generally, the term substituted indicates that one or more of the hydrogen atoms that can be substituted in the given structure have been substituted by specific substituents, where a substituted group can have a substituent in each of the positions that can be substituted, and when more than one position in the given structural formula can be substituted by one or more specific substituents, then the substituents can be substituted in the positions either in an identical or different manner. In the present invention, an OCa-Cb alkyl group is a saturated alkoxy group, either linear or branched, containing a number of carbon atoms ranging from a to b, such as methoxy, ethoxy, propoxy, or isopropoxy. For example, an OC1-C10 alkyl group represents a saturated alkoxy group, either linear or branched, containing from 1 to 10 carbon atoms. A C3-C7 cycloalkyl group is a cyclic alkyl group containing from 3 to 7 carbon atoms and consisting solely of carbon and hydrogen, such as cyclopropyl, 2-methylcyclopropyl, and cyclopentyl. A C1-C5 alkoxy group represents a group containing from 1 to 5 carbon atoms and one oxygen atom, such as methoxy, ethoxy, propoxy, or isopropoxy. A C5-C12 aryl group represents a cyclic and aromatic group containing from 5 to 12 carbon atoms, such as phenyl.A C5-C12 heteroaryl group represents a cyclic, aromatic group containing 5 to 12 carbon atoms and more than one heteroatom (including, but not limited to, an oxygen (O) atom, a sulfur (S) atom, or a nitrogen (N) atom), such as a pyrrolyl or pyridyl group. A nitrogen-containing Cn-Cm cycloalkyl group is a cycloalkyl group with 5 to 12 carbon atoms and one nitrogen atom, such as a tetrahydropyrrolyl or piperidinyl group. An NHC1-C20 alkyl group is a secondary amino group substituted with a saturated alkyl group, either linear or branched, containing 1 to 20 carbon atoms, such as NHCH3 and NHCH2CH3. In some technical solutions, X in the glutamine derivative with formula (I) is a nitrogen-containing C4-C10 cycloalkyl group. Furthermore, X is preferably a tetrahydropyrrolidine group or a piperidinyl group, either substituted or unsubstituted. Furthermore, when X is a substituted tetrahydropyrrolidine group or a piperidinyl group, it is a tetrahydropyrrolidine group or a piperidinyl group that is substituted with 1 to 5 Ci-Ce alkyl groups, either linear or branched. bbcan / i^nz / q / Yi In some forms, X in the glutamine derivative with formula (I) is the: , or the In some other forms, X in the glutamine derivative with formula (I) is H+can / i znz / zi / Yl· el: , or the In some forms, X in the glutamine derivative with formula (I) is an NHC1-C20 alkyl group. Furthermore, when X is an NHC1-C20 alkyl group, the alkyl group is a linear alkyl group. Furthermore, X is preferably an NHC1-C10 alkyl group, wherein the alkyl group is a linear alkyl group. In some embodiments, In addition to the above, when X is an NHC1-C20 alkyl group, the alkyl group is a branched alkyl group. Furthermore, when X is preferably an NHC1-C10 alkyl group, the alkyl group is a branched alkyl group. In some forms, X includes, but is not limited to, NH-CH-(CH3)2 and NHC-(CH3)3. In some forms, X in the glutamine derivative with formula (I) is an N(Ci-C2o)2 alkyl group. Furthermore, the alkyl group is preferably a linear alkyl group. Furthermore, when the alkyl group is preferably a linear alkyl group, X is preferably an N-(Ci-Cio alkyl group)2. In some embodiments, In some other embodiments, X in the glutamine derivative with formula (I) is an N-(alkyl group 61-620)2, wherein the alkyl group is a branched alkyl group. Furthermore, X is preferably an N-(61-610 alkyl group)2, wherein the alkyl group is a branched alkyl group. In some forms, Y in the glutamine derivative with formula (I) is an OH. In some other forms, Y in the glutamine derivative with formula (I) is an alkyl group O61-620· Furthermore, the alkyl group is a linear alkyl group. In some embodiments, Y is selected from: OCH3, OCH2CH3, O(CH2)2CH3, O(CH2)3CH3, O(CH2)4CH3, O(CH2)5CH3, O(CH2)6-CH3, Ο(6Η2)76Η3, O(CH2)8CH3, and O(CH2)9CH3. In addition, when Y is an OC1-C20 alkyl group, the alkyl group is a branched alkyl group. Furthermore, when Y is preferably an OC1-C10 alkyl group, the alkyl group is a branched alkyl group. In some forms, Y includes, but is not limited to, OCH(CH3)2 and OC(CH3)3. In some forms, in the glutamine derivative with formula (I), R1 is an R1aS(=O)2 or H, and R2 is an R2aS(=O)2. Furthermore, R1 is preferably H. In some forms, in the glutamine derivative with formula (I), R1 is an R1bS(=O)2 or H, and R2 is an R2bS(=O)2. Furthermore, R1 is preferably H. In some forms, in the glutamine derivative with formula (I), R1 is an R1a6(=O) or H, and R2 is an R2aC(=O). Furthermore, R1 is preferably H. In some forms, in the glutamine derivative with formula (I), R1 is an R1b6(=O) or H, and R2 is an R2bC(=O). Furthermore, R1 is preferably H. In some forms, in the glutamine derivative with formula (I), each of R1ay / or R2a is a C5-C12 aryl group, either substituted or unsubstituted. In addition, the unsubstituted C5-C12 aryl group includes, but is not limited to, a cyclopentadienyl group, a phenyl group, or a naphthyl group. I bbCQn / l 7O7 / 3 / YL In some modalities, R1ay / or R2ason. In addition, when R1ay / o R2ason is a substituted C5-C12 aryl group, the group I bbCQn / l 7O7 / 3 / YL C5-C12 aryl is a C5-C12 aryl group that is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group that is substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. Furthermore, the C5-C12 aryl group is preferably a Ce aryl group. Specifically, R1ay / or R2a is a substituted phenyl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a Cr C5 alkyl group that is substituted with X2, wherein Xa is selected from: F, Cl, Br, or I. In some modalities, the R1ay / or the R2ason In some forms, in the glutamine derivative with formula (I), R1ay / or R2a are a C5-C12 -(alkylidene C1-C4) -aryl group, either substituted or unsubstituted. Furthermore, when R1ay / or R2a are an unsubstituted C5-C12 -(alkylidene Ci-C4)-aryl group, the C5-C12 aryl group includes, but is not limited to, a cyclopentadienyl group, a phenyl group, or a naphthyl group, and preferably the alkylidene is a methylene group. In some forms, the R1ay / or the R2ason (a benzyl group). Furthermore, when R1ay / or R2a are substituted C5-C12 -(alkylidene Ci-C4)-aryl groups, the C5-C12 aryl group is a C5-C12 aryl group that is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. Furthermore, the C5-C12 aryl group is preferably a Ce aryl group. Specifically, R1ay / or R2a is a substituted benzyl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1C5 alkyl group which is substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. ML / t / ZUZ I / U0044 I In some forms, in the glutamine derivative with formula (I), R1ay / or R2a are a C5-C12 heteroaryl group, either substituted or unsubstituted. Furthermore, when R1ay / or R2a are unsubstituted C5-C12 heteroaryl groups, such C5-C12 heteroaryl group includes, but is not limited to, a pyrrolyl-alkyl group, a pyrazolyl group, or a pyridyl group. Furthermore, when R1ay / or R2a are substituted C5-C12 heteroaryl groups, the C5-C12 heteroaryl group is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Bro I. Furthermore, the C5-C12 heteroaryl group is preferably a pyrrolyl group, a pyrazolyl group, or a pyridyl group. In some modalities, the R1ay / or the R2ason: , or the In some forms, in the glutamine derivative with formula (I), R1ay / or R2a are a -(C4-alkylidene)-heteroaryl C5-C12 group, either substituted or unsubstituted. Furthermore, the -(alkylidene Ci-C4)-heteroaryl C5-C12 group is an unsubstituted -(alkylidene Cr C4)-heteroaryl C5-C12 group, wherein the C5-C12 heteroaryl group includes, but is not limited to, a pyrrolyl group, a pyrazolyl group, or a pyridyl group, and the C1-C4 alkylidene is preferably a methylene group. bbcan / i znz / zi / Yl· In addition to the above, when R1ay / or R2a are a substituted C5-C12 C1-C4 (alkylidene)heteroaryl group, the C5-C12 heteroaryl group is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group that is substituted with X2, wherein X2 is selected from: F, Cl, Br, or I. Furthermore, the C5-C12 heteroaryl group is preferably a pyrrolyl group, a pyrazolyl group or a pyridyl group, and the C1-C4 alkylidene group is preferably a methylene group. In some embodiments, the glutamine derivative of the present invention includes the above compounds and a racemate thereof, a stereoisomer thereof, a geometric isomer thereof, a tautomer thereof, a solvate thereof, or a salt thereof acceptable for use in food. In some embodiments, in the glutamine derivative with formula (I), Y is an OH, and the glutamine derivative may further exist in the form of a food-acceptable salt, wherein said food-acceptable salt is a salt of a metal ion. Furthermore, the metal ion is a monovalent metal ion, a divalent metal ion, or a trivalent metal ion. Specifically, the monovalent metal ion includes, but is not limited to: sodium ion, potassium ion, lithium ion, and ammonium ion; the divalent metal ion includes, but is not limited to: calcium ion, magnesium ion, zinc ion, copper ion, ferrous ion, and manganese ion; and the trivalent metal ion includes, but is not limited to: iron ion, nickel ion, chromium ion, and aluminum ion. In some forms, the metal ion is a zinc ion. In some other forms, the metal ion is a copper ion. In some other forms, the metal ion is a sodium ion. In some other forms, the metal ion is a calcium ion. In some other forms, the metal ion is an iron ion. Preparation and purification of compounds The glutamine derivative of formula (I) involved in the present invention is prepared using glutamic acid (abbreviated Glu) as the starting material. The chemical reactions involved mainly include esterification of carboxyl groups, acylation of amino groups, and aminolysis of esters and, if necessary, hydrolysis of esters. In some embodiments, when Y in the glutamine derivative with formula (I) is an OH, then said glutamine derivative is prepared by the method shown in formula (II), wherein di-tere-butyl glutamate (FBu-Glu) can be produced by a dehydration condensation between glutamic acid and tert-butanol under esterification conditions: I bbCQn / l 7O7 / 3 / YL Formula (II) It should be noted that X and R1 shown in formula (II) represent only substituent groups; if the indicative materials XH or R1-OH are not a single substance, then X or R1 should be considered as a collection of substituents. The symbol t-Bu represents a tert-butyl group as a protecting group of the carboxyl group, DCM represents dichloromethane, and F3CCOOH represents trifluoroacetic acid. Furthermore, the abbreviation rt. stands for room temperature, EtN(Pr-i)2 represents diisopropylethylamine, DMF is N,N-dimethylformamide, and HBTU is O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium-hexafluorophosphate (a coupling reagent). Furthermore, when Y in the glutamine derivative with formula (I) is an OH, said glutamine derivative can react with a metal base of a main group I or main group II metal, or react with a metal halide under alkaline conditions, in order to obtain a metal ion salt of the glutamine derivative. Optionally, the metal base is selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, and magnesium hydroxide. Optionally, the metal halide is a metal chloride, a metal bromide, or a metal iodide. Specifically, a metal chloride is: zinc chloride, calcium chloride, magnesium chloride, iron chloride, copper chloride, manganese chloride, cobalt chloride, or nickel chloride; a metal bromide is: zinc bromide, calcium bromide, magnesium bromide, iron bromide, copper bromide, manganese bromide, cobalt bromide, or nickel bromide; a metal iodide is: zinc iodide, calcium iodide, magnesium iodide, iron iodide, copper iodide, manganese iodide, cobalt iodide, or nickel iodide. In some embodiments, when Y in the glutamine derivative with formula (I) is an OC1-C20 alkyl group, the glutamine derivative is prepared by the method shown in formula (III), wherein di-tert-butyl glutamate (t-Bu-Glu) can be produced by a dehydration condensation between glutamic acid and tert-butanol under esterification conditions: I bbCQn / l 7O7 / 3 / YL Formula (III) > Π 15 ν C It should be noted that the Y, X, and R1 shown in formula (III) only represent substituent groups; in the event that the starting material R1- or If OH is not a single substance, then R1 should be considered as a collection of substituents. The symbol t-Bu represents a tert-butyl group acting as a protecting group for the carboxyl group, DCM represents dichloromethane, and F3CCOOH represents trifluoroacetic acid. Furthermore, the abbreviation rt. stands for room temperature, EtN(Pr-i)2 represents diisopropylethylamine, DMF represents N,N-dimethylformamide, and HBTU is O(benzotriazol-1-yl)-N,N,N',N'-tetramethyluroniumhexafluorophosphate (coupling reagent). In some embodiments, the glutamine derivative is a chiral compound, prepared from dibutyl glutamate with a chiral structure (as shown in formula (IV)) or its racemate. The glutamine derivative of the present invention may be selected from stereoisomers such as the levo L-(-)-glutamine derivative (formula (V)), the dextro D-(+)-glutamine derivative (formula (VI)), and the racemic DL-(+)-glutamine derivative. Formula (V) Formula (VI) It should be noted that the R1 shown in formula (V) and formula (VI) only represents identical and / or different substituent groups. In some forms, chiral stereoisomers of the glutamine derivative can undergo a transformation of their spatial configuration under appropriate conditions. For example, a conformational interconversion of a glutamine derivative, resulting in tautomers, is as shown in formula (Vil): I bbCQn / IZPZ / ^ / YIL Formula (Vile) When the reaction of the reagents involved results in the corresponding glutamine derivative that has a rigid structure, the reaction can produce different geometric isomers from the reagents. The stereoisomers, geometric isomers, and tautomers mentioned above are also included within the scope of the present invention. The term stereoisomers refers to compounds that have the same chemical structure but with a different arrangement of their atoms or groups in space. These include enantiomers, diastereomers, conformational isomers, geometric isomers, and atropisomers. Enantiomers are two isomers that are mirror images of each other and cannot be superimposed. Diastereomers are two stereoisomers that have two or more chiral centers but are not mirror images of each other and have different physical properties such as melting point, boiling point, spectral properties, and reactivity. A mixture of diastereomers can be separated using high-resolution analytical processes such as electrophoresis or chromatography.The term tautomers refers to structural isomers with different energies that can be converted into each other across a low-energy barrier. In some embodiments, the process for preparing the glutamine derivative provided in the present invention also involves the isolation, purification, or recrystallization of the reaction product. The reaction product can be obtained as a crude product of the reaction system by removing the solvent. In order to obtain a solid substance with greater chemical purity and a lower degree of impurities, the crude product can be dissolved and crystallized, precipitated, or recrystallized in alcoholic solvents, alcohol-water solvents, or other organic solvents that can be used for recrystallization of the product under suitable conditions of temperature, light, and mechanical vibration, and subsequently isolated to obtain the glutamine derivative in a certain crystalline state.A glutamine derivative in a certain crystalline state refers to a crystal of the glutamine derivative or a solvate of the glutamine derivative. The solvate of the glutamine derivative can be selected from either a hydrate of the glutamine derivative or an ethanolate of that glutamine derivative. The solvate involved in the present invention refers to a co-crystalline complex formed by combining the compound of the present invention with solvent molecules, whether chemically equivalent or not, through non-covalent intermolecular forces caused by external and internal factors when the compound comes into contact with the solvent. Solvents for solvate formation include, but are not limited to: water, acetone, ethanol, methanol, dimethyl sulfoxide, ethyl acetate, acetic acid, and isopropanol. The term hydrate refers to a complex or crystal in which the solvent is water, i.e., chemically equivalent or non-chemically equivalent water molecules combined with the compound by non-covalent intermolecular forces. In order to obtain a solid substance with greater chemical purity and a lower degree of impurities, the process for preparing the glutamine derivative provided in the present invention may also involve a saltification process. This saltification process refers to a process for forming a salt from the acylated glutamine derivative with its corresponding organic base, inorganic base, organic acid, or inorganic acid, by means of acid-base neutralization, acid-base coordination, or acid-base chelation, and thereby precipitating the salt to obtain a salt acceptable for use in food. The inorganic acid includes, but is not limited to: hydrochlorides, hydrobroms, phosphates, sulfates, nitrates, or a combination thereof. The organic base includes, but is not limited to, ammonia or triethylamine.Inorganic bases include, but are not limited to, sodium hydroxide, potassium hydroxide, magnesium hydroxide, or calcium hydroxide. Acceptable salt for use in food refers to a salt of a glutamine derivative with an organic base, an inorganic base, an organic acid, or an inorganic acid—compounds that are non-toxic to animals. The term "acceptable for use in food" means that the substance or composition must be chemically or toxicologically suitable and relevant for the resulting food or for feeding animals. In some embodiments, the glutamine derivative of the present invention is an ester derived from glutamine. During the salification process, an acid-base coordination and / or an acid-base chelated salt is formed from the derivative with an inorganic acid or an organic acid, wherein the organic acid includes, but is not limited to: acetate, maleate, succinate, mandelate, fumarate, malonate, malate, 2-hydroxypropionate, pyruvate, oxalate, glycolate, salicylate, glucuronate, galactitolate, citrate, tartrate, aspartate, glutamate, benzoate, p-toluene, cinnamate, p-toluenesulfonate, benzenesulfonate, methanesulfonate, ethanesulfonate, triflate, or a combination thereof. Use of the glutamine derivative of the present invention The glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, provided by the present invention, can be used in the preparation of animal feed additives. The term "animal" as used in the present invention refers to human beings or farm animals that cannot synthesize organic substances from inorganic substances, but can only use organic substances as food for vital activities such as feeding, digestion, absorption, respiration, circulation, excretion, sensation, movement, and reproduction. The term "farm animals" includes poultry, cattle, aquatic animals, and other artificially fed animals, including pets such as cats and dogs. The term "livestock" includes, for example, pigs, cows, horses, goats, sheep, deer, and any species of a variety of useful rodents. The term "poultry" includes, for example, chickens, ducks, geese, quail, and pigeons. The term "aquatic animals" includes, for example, fish, shrimp, turtles, and softshell turtles. The glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, provided in the present invention, can be used in the preparation of non-nutritive food additives for the purpose of improving the productive performance of animals at each stage of their growth, where the animals can be selected from cattle, poultry, aquatic animals, or pets, at each stage of their growth. In addition, livestock includes, but is not limited to: pigs, cows, horses, rabbits, sheep, martens, and donkeys; poultry includes, but is not limited to: chickens, turkeys, ducks, geese, quail, or pigeons; aquatic animals include, but are not limited to: fish, shrimp, turtles, crabs, softshell turtles, bullfrogs, eels, and loaches; pets include, but are not limited to, dogs or cats of various subspecies. In one embodiment, the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, provided by the present invention, are used in the preparation of food additives for the purpose of improving the productive performance of pigs, showing an improving effect on average daily weight gain and feed efficiency. In another embodiment, the food additives prepared from the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, provided by the present invention, can significantly improve the productive performance of broiler chickens or laying hens. In one embodiment, the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, provided by the present invention, are used in the preparation of food additives for the purpose of improving the productive performance of fish. The food-acceptable salt of the glutamine derivative provided by the present invention and used in the preparation of animal feed additives is a metal ion salt. Optionally, the acceptable food salt of the glutamine derivative is a metal ion salt of the glutamine derivative with formula (I). Furthermore, Y in the glutamine derivative with formula (I) is an OH, and the metal ion salt is a salt that meets the requirements for the preparation of food additives or food itself, and is formed by ion exchange between the OH group and a metal ion when Y in the glutamine derivative with formula (I) is an OH. Specifically, the metal ion is selected from among a monovalent metal ion, a divalent metal ion, or a trivalent metal ion. In some forms, the monovalent metal ion is a: sodium ion (Na(l)), potassium ion (K(l)) or lithium ion (Li(l)). In some embodiments, the divalent metal ion is a: calcium ion Ca(ll), magnesium ion Mg(lI), copper ion Cu(ll), zinc ion Zn(lI), ferrous ion Fe(ll), manganese ion Mn(ll), cobalt ion Co(ll), or nickel ion Ni(II). In one embodiment, the metal ion salt of the glutamine derivative used in the preparation of animal feed additives is a zinc ion salt, and the animal feed additives are organic zinc preparations for animals, as a substitute for high-level inorganic zinc. In one form, the metal ion salt of the glutamine derivative that is I bbCQn / l 7O7 / 3 / YL used in the preparation of animal feed additives is a copper ion salt, and animal feed additives are organic copper preparations for animals, as a substitute for high-level inorganic copper for animals. In one embodiment, the metal ion salt of the glutamine derivative used in the preparation of animal feed additives is an iron ion salt, and the animal feed additives are iron supplements for animals. In some forms, the trivalent metal ion is an aluminum ion Al(lll), a chromium ion Cr(lll), or an iron ion Fe(III). Food compositions involved in the present invention A food composition contains at least one of the following acceptable food compounds: glutamine derivative, racemate, stereoisomer, geometric isomer, tautomer, solvate, and salt, and a suitable food additive. The food additive may be a vehicle, diluent, excipient, solvent, or a combination thereof. The foods involved in the present invention refer to products that are processed and manufactured industrially for animal consumption. The term composition refers to a collection of compounds that contains one or more compounds as effective ingredients. The terms comprise, include, contain, and “with” as well as variants thereof in the present invention mean an open expression, which includes the contents explicitly stated in the present invention and does not exclude the contents of other aspects. The term "vehicle" refers to a substance suitable for use in feed, which can carry active ingredients, enhance their dispersibility, and exhibit both high chemical stability and adsorption. A vehicle can be either organic or inorganic. Organic vehicles are materials rich in crude fiber, including, but not limited to, corn flour, corn cob flour, wheat bran, rice hull flour, defatted rice bran, rice bran, corn stalk flour, and peanut hull flour. Inorganic vehicles are minerals, primarily calcium salts and silicon oxides, used for the production of trace element premixes. These include, but are not limited to, calcium carbonate, silicate, vermiculite, zeolite, and meerschaum. The term diluent refers to a substance that uniformly disperses the additive's raw materials and dilutes the high concentrations of those raw materials in the additive into low-concentration premixing agents or premixes. These premixes separate trace components and reduce interactions between the active ingredients, thereby increasing the stability of the active ingredients without affecting the physical and chemical properties of the substances involved. Such diluents can be organic or inorganic. Organic diluents include, but are not limited to: corn flour, degermed corn flour, dextrose (glucose), sucrose, semolina with bran, sautéed soy powder, wheat middlings, and corn gluten meal. Inorganic thinners include, but are not limited to: limestone, calcium dihydrogen phosphate, shell powder, kaolin (white clay), table salt, and sodium sulfate. The term “excipient” refers to a wetting agent that induces the inherent viscosity of a substance, an adhesive that binds substances together, a disintegrant that breaks the entire sheet of the substance into many fine particles, a retention aid that reduces friction between particles, or an anti-adherent agent for the purpose of preventing the material from adhering, which includes, but is not limited to: magnesium stearate, talc, magnesium lauryl sulfate, starch, starch slurry, inorganic salts, water, dextrin, and powdered sugar. The term solvent refers to the solvent needed to dissolve or disperse solids, which includes, but is not limited to, water, ethanol, and glycerin. In some forms, the food composition also contains an additional additive for animal feed and / or raw materials for animal feed. Animal feed additives include nutritive feed additives, general feed additives, or medicinal feed additives. Nutritive feed additives refer to substances, in small or trace amounts, that are added to a compound feed for the purpose of balancing the nutrients in the feed, improving feed utilization, and directly exerting nutritive effects on animals. These include amino acids, amino acid salts and their analogues, vitamins and vitamin-like substances, mineral elements and their complexes (chelates), microbial enzyme preparations, or non-protein nitrogen. General food additives, also called non-nutritive additives, refer to non-nutritive substances that are added to food for the purpose of improving food utilization and ensuring both the quality and properties of the food, and which are also beneficial to animal health or metabolism, and these include: growth promoters, flavorings, attractants, vermifuges, food conditioners, food modifiers, food preservation agents and additives of Chinese herbal medicine. More specifically, non-nutritive additives are growth promoters, which include, but are not limited to: butyric acid, calcium butyrate, sodium butyrate, tannic acid, p-thymol, p-thymol esters, p-thymol salts, 2-hydroxybenzoic acid, β-acids, β-acid esters, β-acid salts, hexahydro-β-acids, hexahydro-β-acid esters, hexahydro-acid salts, benzoic acid or calcium benzoate, zinc oxide, zinc sulfate, and zinc chloride. In one version, the non-nutritive additive is calcium butyrate. In another form, the non-nutritive additive is tannic acid. Specifically, medicinal feed additives include, but are not limited to, veterinary drugs premixed with a vehicle or diluent that are capable of both preventing animal diseases and promoting animal growth and that may be present in feed for long-term use. Even more specifically, medicinal food additives are antibiotics for use in food, and such antibiotics for use in food include, but are not limited to: polymyxin, salinomycin, avilamycin, bacitracin, virginiamycin, nasitide, flavomycin, enramycin, kitasamycin, olaquindox, oxytetracycline, or chlortetracycline. In some forms, compositions containing the glutamine derivative, or the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, further contain one or more of the nutritive food additives, general food additives, and medicinal food additives. In some forms, raw materials for animal feed include both cereals and their processed products; oilseeds and their processed products; legumes and their processed products; tubers / tuberous roots and their processed products; other seeds and fruits as well as their processed products; fodder / forage fiber and its processed products; various plants and algae and their processed products; dairy products and their by-products; terrestrial animal products and their by-products; fish and other aquatic organisms as well as their by-products; products and by-products of both minerals and microbial fermentation; as well as other raw materials for feed. Use of food compositions The present invention involves the use of the above food compositions which contain the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food. In some forms, food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, may be used in the preparation of animal feed additives. Animal feed additives prepared using feed compositions containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in feed, are feed additives for livestock, feed additives for poultry, feed additives for aquatic animals, or feed additives for pets. Specifically, food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, are employed for the purpose of preparing feed additives for livestock, where livestock includes, but is not limited to: pigs, cows, sheep, horses, rabbits, and minks, at various stages of their growth. Specifically, food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, are employed for the purpose of preparing feed additives for poultry, where such poultry include, but are not limited to: chickens, ducks, geese, and pigeons, at various stages of their growth. Specifically, food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, are employed for the purpose of preparing food additives for aquatic animals, where such aquatic animals include, but are not limited to: fish, shrimp, crabs, softshell turtles, and eels, at various stages of their growth. Specifically, food compositions containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in food, are employed for the purpose of preparing pet food additives, in linean / Lznz / q / Yi where such pets include, but are not limited to, captive-bred dogs or cats. In some forms, animal feed additives prepared from feed compositions containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in feed, are premixes, multiple premixes, aqueous solutions, or granules. In some forms, the food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food, are used in the preparation of animal feed. Animal feeds prepared using feed compositions containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in feed, are livestock feeds, poultry feeds, aquatic animal feeds, or pet feeds. Specifically, food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food are employed for the purpose of preparing feed for livestock, where livestock includes, but is not limited to: pigs, cows, sheep, horses, rabbits, and minks, at various stages of their growth. Specifically, food compositions containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in food are employed for the purpose of preparing feed for poultry, where such poultry include, but are not limited to: chickens, ducks, geese, and pigeons, at various stages of their growth. Specifically, food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food are employed for the purpose of preparing food for aquatic animals, where such aquatic animals include, but are not limited to: fish, shrimp, crabs, softshell turtles, and eels, at various stages of their growth. Specifically, food compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer of Linean / Lznz / q / Yi itself, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food are employed for the purpose of preparing pet food, where such pets include, but are not limited to, dogs or cats kept in captivity. In some forms, animal feeds prepared from feed compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in feeds, are feed alone, concentrated feeds, formula feeds, multiple premixes, or concentrated supplements. Specifically, these compound foods are complete compound foods. Methods to improve the productive performance of farm animals In some feeding systems, farmers can significantly improve the productive performance of animals by supplying the animals with feed in combination with feed additives containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in feed. In some forms, feed additives are premixes, multiple premixes, granules, or aqueous solutions, and are supplied to animals after being mixed with animal feed. The animals are: livestock, poultry, aquatic animals, or pets. Specifically, livestock includes, but is not limited to: pigs, cows, sheep, horses, rabbits, and minks, at various stages of their growth; poultry includes, but is not limited to: chickens, turkeys, ducks, geese, and pigeons, at various stages of their growth; aquatic animals include, but are not limited to: fish, shrimp, crabs, softshell turtles, and eels, at various stages of their growth; and pets include, but are not limited to, captive-bred dogs or cats. In one embodiment, farmers supply feed in combination with feed additives containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in feed, to weaned pigs, which can significantly improve both the average daily weight gain and feed efficiency of weaned piglets. In one model, farmers supply the food in combination Linean / Lznz / q / Yi with feed additives containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in feed, to broiler chickens, which can significantly reduce the feed conversion ratio and improve feed efficiency of broiler chickens. In one embodiment, farmers supply the feed to fish in combination with feed additives containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in food. In one embodiment, farmers supply young dogs with food in combination with food additives containing the glutamine derivative, racemate thereof, stereoisomer thereof, geometric isomer thereof, tautomer thereof, solvate thereof, or salt thereof acceptable for use in food. In another modality, the productive performance of animals can be significantly improved when farmers supply the animals with feed compositions containing the glutamine derivative, the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, or the salt thereof acceptable for use in food. Optionally, feed compositions are feed additive premixes, multiple feed additive premixes, granules, or aqueous solutions, which are supplied to animals in combination with feed. In one form, food compositions are premixes of food additives. In one modality, food compositions are multiple premixes of food additive compounds. Optionally, feed compositions are concentrated feeds, compound feeds, formula premixes, or concentrated supplements, which are supplied directly to the animals as animal feed. In one modality, the food compositions are complete formula foods. DETAILED DESCRIPTION OF THE MODALITIES The embodiments of the present invention will be described in greater detail below with examples; however, those skilled in the art should understand that the following examples are used only to illustrate the present invention and should not be considered as limiting its scope. Where no specific conditions are indicated in the examples, they should be carried out according to conventional conditions or conditions recommended by the manufacturer. In cases where reagents or instruments involved are presented without the names given by the manufacturers, they are all conventional products that can be purchased commercially. Breeding experiments The glutamine derivatives involved in breeding experiments as shown in Table 1. Table 1: Glutamine derivative. X o=¿ / N \ )—z O=< Y > Serial Number R1 R2 YX Compound 1 γH 0 οΛ / hcA An^ H Compound 2 YH cA HO^ H Compound 3 YH 0 0^ hcA H Compound 4 YH 0 HO^ H Compound 5 YH 0 qA / hcA ANQ Compound 6 YH 0 0^ H Compound 7 YH o cY γθ · Zn2+ H Compound 8 YH 0 σ7 γθ · Cu2+ H Compound 9 YH 0 q' / γθ · Ca2+ H Compound 10 YH O rY7 hcA H Compound 11 YH o fY7, Me hcA H Compound 12 YH or ΓγY HO HO^ '^N'^ H Compound 13 \HO HO^ H Compound 14 YH O hcA H Compound 15 γH or HO^ H Note: It should be clarified that the Y groups in compounds 8 to 10 only represent the combination of substances, but do not show the structures of the salt represented by the compounds. i bbcan / i zn7 / 3 / vl· Example 1: Effect of glutamine derivatives on the productive performance of pigs. Four hundred and eighty 65-day-old bacon pigs of Duroc x Landrace x Yorkshire crossbreed and with similar body weights were randomly divided into 16 groups, with 3 replicates per group and 10 pigs (half male and half female) per replicate. The pens and equipment were sterilized prior to the experiment. During the experiment, the piglets were housed in separate areas within the same pen under the same feeding and management conditions. The piglets had free access to drinking water and feed, which was provided twice daily.The groups comprised a control group and treatment groups 2 through 16. The control group received only the basal daily ration, while piglets in treatment groups 2 through 16 received the basal ration in combination with 800 ppm of different glutamine derivatives, as shown in Table 2. No other antioxidants or growth promoters were administered to the treatment groups throughout the experiment. The duration of the experiment was 28 days.On the day the piglets reached 93 days of age and without subjecting them to fasting from water or food for 12 hours, with each replicate being considered as a unit, the average daily feed intake (ADFI, g / d * each piglet), the average daily weight gain (ADG, g / d * each piglet) and the feed conversion ratio (FCR) were calculated. Average daily feed intake = (total weight of feed provided - weight of leftover feed) / (number of days × number of piglets per replicate). Average daily weight gain = (average final body weight average initial body weight) / number of days. Feed conversion ratio = average daily feed intake / average daily weight gain. The results are shown in Table 2, where the effect of the samples on the productive performance of the piglets was evaluated in terms of three aspects: feed intake, weight gain, and feed efficiency. Table 2. Effect of glutamine derivatives on the productive performance of piglets Sample Group ADFI (g / d per piglet) ADG (g / d per piglet) FCR 1 - 1586 588 2.695 2 Compound 1 1657 661 2.506 3 Compound 2 1648 651 2.531 4 Compound 3 1691 670 2.524 5 Compound 4 1602 641 2.500 6 Compound 5 1633 651 2.510 7 Compound 6 1615 646 2.499 8 Compound 7 1674 672 2.491 9 Compound 8 1670 671 2.488 10 Compound 9 1636 652 2.511 11 Compound 10 1607 657 2.508 12 Compound 11 1592 634 2.512 13 Compound 12 1599 633 2.528 14 Compound 13 1609 627 2.566 15 Compound 14 1582 621 2.548 16 Compound 15 1670 650 2.571 As can be seen from the results, the samples did not show a significant effect on feed intake by the piglets, although an increase in feed intake was observed in several of the treatment groups compared to the control group. However, the average daily weight gain of each treatment group increased to varying degrees regardless of the change in feed intake. In terms of feed conversion ratio, a reduction ranging from 4.6% to 7.6% was observed in each treatment group compared to the control group, with treatment groups 8 through 10 exhibiting the most significant results. Example 2: Effect of glutamine derivatives on the productive performance of broiler chickens. The experiment was conducted using a single-factor randomized design. 720 one-day-old yellow broiler chicks of similar body weight (averaging 50 g) were randomly divided into 16 groups, with three replicates per group and an equal number of males and females. Each replicate consisted of 15 yellow broiler chicks. The poultry house and equipment were sterilized before the experiment. During the experiment, the broilers were kept in separate areas within the same poultry house under identical feeding and management conditions. The basal ration consisted primarily of corn and soybean meal. No other antioxidants or growth promoters were administered to any treatment group throughout the experiment.The groups comprised a control group and treatment groups 2 through 16. Broiler chickens in the control group were fed only the basal ration, while broiler chickens in treatment groups 2 through 16 were fed a basal ration in combination with 750 ppm of different glutamine derivatives, as shown in Table 3. The experiment lasted 20 days. Broiler chickens had ad libitum access to feed and drinking water and were fed twice daily.On the day the broiler chickens reached 21 days of age (with a 12-hour food fast, and no water fast), with each repetition being considered as one unit, the body weights of the broiler chickens were measured in order to calculate the average daily feed intake (ADFI, g / d per broiler chicken), the average daily weight gain (ADG, g / d per broiler chicken), and the feed conversion ratio (FCR). Feed conversion ratio (FCR) = Average daily feed intake / Average daily weight gain. Table 3. Effect of glutamine derivatives on the productive performance of broiler chickens. Sample Group ADFI (g / d per broiler chicken) ADG (g / d per broiler chicken) FCR 1 - 31.1 12.6 2.47 2 Compound 1 32.8 14.8 2.22 3 Compound 2 31.5 14.1 2.23 4 Compound 3 31.9 14.4 2.21 5 Compound 4 32.1 14.3 2.25 6 Compound 5 30.9 13.7 2.26 7 Compound 6 31.2 14.2 2.20 8 Compound 7 31.7 14.5 2.18 9 Compound 8 30.6 14.2 2.16 10 Compound 9 32.5 14.8 2.20 11 Compound 10 32.2 14.5 2.22 12 Compound 11 30.8 13.8 2.24 13 Compound 12 31.6 14.0 2.26 14 Compound 13 31.3 13.7 2.28 15 Compound 14 31.8 14.0 2.27 16 Compound 15 32.4 14.6 2.22 The results are shown in Table 3. As can be seen from the results, the samples did not have a significant effect on the feed intake of the broiler chickens. In terms of average daily weight gain, the treatment groups showed a significant increase ranging from 8.7% to 17.4% compared to the control group. The samples showed a significant improvement in the feed conversion ratio of each treatment group, with reductions ranging from 7.6% to 10.9%. Among others, treatment groups 8 through 10, which were supplied with zinc salt, copper salt, and calcium salt of N-benzoyltheanine, showed a reduction ranging from 10.9% to 12.5% ​​compared to the control group. Example 3: Application of glutamine derivatives in fish feed. Grass carp were used in this experiment, which was conducted in an aquaculture area of ​​the experimental yard at Guangzhou Insighter. Healthy, uniformly sized grass carp were raised in large net cages for four weeks prior to the experiment. During the experiment, the grass carp were transferred to small floating net cages. Both the small net cages and the acclimation net cages were placed in a 3,500 m² pond in the experimental yard. The pond was 1.5 m deep, and the water was aerated from the bottom. In the experiment, 520 grass carp, which had been fasted for one day, were randomly divided into 13 groups. Each group consisted of four replicates, and each replicate contained 10 grass carp. The grass carp were weighed, with each replicate being considered as a whole.Subsequently, the animals were randomly released into 52 net cages where they were fed different diets. The diets used in this experiment were prepared according to Table 4, with 500 ppm of different glutamine derivatives added to the basal rations of the different treatment groups. Feed restriction was implemented throughout the experiment, and the amount of feed was adjusted once a week. Both the treatment and control groups were fed twice daily (7:30 a.m. and 3:30 p.m.), with their feed levels (based on initial body weight) being identical to achieve a total of 580 g. The experiment lasted 8 weeks. Calculations: Weight gain (%) = (Average final weight - Average initial weight) / Average initial weight χ 100 Feed coefficient = 580 / (Average of final weight - Average of initial weight). Table 4 shows the effect of different glutamine derivatives on the productive performance of herbivorous carp, which was evaluated in terms of two aspects: the rate of weight gain and the feeding coefficient. Table 4: Grouping and results for the evaluation of the application of glutamine derivatives in fish feed. l frican / Lznz / q / Yi Sample Average starting weight (g) Average final weight (g) Weight gain (g) Feeding coefficient 1 - 386 649 68.19 1.93 2 Compound 1 393 678 72.41 1.79 3 Compound 2 405 690 70.47 1.78 4 Compound 3 382 666 74.29 1.79 5 Compound 4 388 675 73.97 1.77 6 Compound 5 396 678 71.27 1.80 7 Compound 6 394 681 72.84 1.77 8 Compound 10 388 669 72.34 1.81 9 Compound 11 399 681 70.73 1.80 10 Compound 12 408 692 69.56 1.79 11 Compound 13 403 687 70.42 1.83 12 Compound 14 397 678 70.70 1.81 13 Compound 15 399 681 70.73 1.80 As can be seen from the results, the treatment groups with glutamine derivatives exhibited an increase ranging from 2.01% to 8.9% in weight gain and a reduction ranging from 5.18% to 8.29% in the feed quotient compared to the control group, indicating a significant improvement in feed efficiency. Although specific examples have been used to illustrate and describe the present invention, it should be noted that many other changes and modifications can be made without departing from the spirit or scope of the present invention. Therefore, all such changes and modifications that fall within the scope of the present invention are included in the appended claims.

Claims

1. The use of a glutamine derivative characterized in that it has a structure of formula (I), of a racemate thereof, of a stereoisomer thereof, of a geometric isomer thereof, of a tautomer thereof, of a solvate thereof, or of a salt thereof acceptable for use in food, in the preparation of animal feed additives: 1 bbcan / i znz / zi / Yl· formula (I), wherein Y is an OC1-C20 alkyl group or an OH; X is a C4-C10 cycloalkyl group containing nitrogen, an NHC1-C20 alkyl group or an N(alkyl group 61-620)25; R1 is R1a6(=O), R1b6(=O), R1aS(=O)2, R1bS(=O)2 or H; R2 is R2a6(=O), R2bC(=O), R2aS(=O)2, or R2bS(=O)2; each of R1b and R2b is, independently, an alkyl group 61-620, a cycloalkyl group 63-67, or either an alkyl group 61-620 or a cycloalkyl group 63-67 that is optionally substituted with one, two, three, four, or five R3s; R3 is a: -OH, -NH2, -6N, -SH, or -X1, wherein X1 is selected from: F, Cl, Br, or I;each of R1a and R2a is, independently, an aryl group 65-612, a heteroaryl group 65-612, a -(alkylidene 6i-64)-ahlo group 65-612, a -(alkylidene C1-C4)heteroaryl group 65-612, or either an aryl group 65-612, a heteroaryl group 65-612, a (alkylidene 6i-64)-aryl group 65-612, or a -(alkylidene 6i-64)-heteroaryl group 65-612, which is optionally substituted with one, two, three, four, or five R4s; R4 is a: -OH, -NH2, -NO2, -ON, -SH, -X2, a C1-C5 alkoxy group, an O1-O5 alkyl group, or an O1-O5 alkyl group substituted with X2, wherein X2 is selected from: F, OI, Br, or I.; 2. The use according to claim 1, characterized in that, R1 is R1aO(=O) or H; R2 is R2a6(=O); each of R1a and R2a is, independently, a C5-C12 aryl group, a C5-C12 heteroaryl group, a -(alkylidene Oi-O4)-ahlo C5-C12 group, a (alkylidene Oi-O4)-heteroahlo C5-C12 group, or either a C5-C12 aryl group, a C5-C12 heteroaryl group, a -(alkylidene Oi-O4)-aryl C5-C12 group, or a -(alkylidene Oi-O4)-heteroahlo C5-C12 group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -6N, -SH, -X2, alkoxy group 61-65, alkyl group 61-65, or an alkyl group 61-65 substituted with X2, wherein the X2 is selected from: F, 6I, Br, or I.

3. The use according to claim 1, characterized in that, R1 is an H; R2 is an R2aC(=O); R2a is a C5-C12 aryl group, a C5-C12 -(alkylidene Ci-C4)-aryl group, or either a C5-C12 aryl group or a C5-C12 -(alkylidene Ci-C4)-aryl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein the X2 is selected from: F, Cl, Br, or I.

4. The use according to claim 1, characterized in that R2a is an aryl group Ce, a -(C4-alkylidene)-aryl group Ce, or either an aryl group Ce or a (C4-alkylidene)-aryl group Ce, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Br, or I.

5. The use according to claim 1, characterized in that R2a is a phenyl group, a -(C4-alkylidene)phenyl group, or a phenyl group or a (C4-alkylidene)phenyl group, which is optionally substituted with one, two, three, four, or five R4s; wherein said R4 is a: -OH, -NH2, -NO2, -CN, -SH, -X2, a C1-C5 alkoxy group, a C1-C5 alkyl group, or a C1-C5 alkyl group substituted with X2, wherein X2 is selected from: F, Cl, Br, or I.

6. The use according to claim 1, characterized in that, R1 is R1bC(=O) or H; R2 is R2bC(=O); each of R1b and R2b is, independently, a C1-C20 alkyl group, a C3-C6 cycloalkyl group, or either a C1-C20 alkyl group or a C3-C7 cycloalkyl group that is optionally substituted with one, two, three, four, or five R3; wherein said R3 is a: -OH, -NH2, -CN, -SH, or -X1, wherein X1 is selected from: F, Cl, Br, or I.

7. The use according to claim 1, characterized in that, R1 is either an H; R2 is an R2bC(=O); R2b is a C1-C20 alkyl group or is a C1-C20 alkyl group that is optionally substituted with one, two, three, four, or five R3; wherein said R3 is a: -OH, NH2, -CN, -SH or -X1, wherein X1 is selected from: F, Cl, Br, or I.

8. The use according to claim 1, characterized in that, Y is an OC1-C20 alkyl group.

9. The use according to claim 1, characterized in that, X is a C4-C10 cycloalkyl group which contains nitrogen.

10. The use according to claim 1, characterized in that X is an NHC1-C20· alkyl group 11. The use according to claim 10, characterized in that, X is 1 nncan / i 707 / 3 / yl an NHC1-C10 alkyl group.

12. A food composition, characterized in that the food composition contains at least one of the following: the glutamine derivative with formula (I), the racemate thereof, the stereoisomer thereof, the geometric isomer thereof, the tautomer thereof, the solvate thereof, and the salt thereof acceptable for use in food, as described in any one of claims 1 to 11, and a food adjuvant suitable for food.

13. The food composition according to claim 12, characterized in that the food composition further contains an additional animal feed additive, wherein the additional animal feed additive is selected from at least one nutritive food additive, a general food additive, and a medicinal food additive.

14. The food composition according to claim 12 or 13, characterized in that the food composition further contains a raw material for animal feed.

15. The use of the food composition of any one of claims 12 to 13 in the preparation of an animal feed additive.

16. The use of the food composition of any one of claims 12 to 14 in the preparation of an animal feed.