| In young animals,arginine plays an important role in cell information transmission and biological metabolism.However,breast milk supplementation and arginine synthesized by young animals themselves are difficult to meet the nutritional needs,so the supplement and replacement of the lack of arginine in young animals has become the current research focus.The endogenous synthesis of arginine is achieved through the ornithine cycle.During this process,ornithine is converted into citrulline by carbamoyl phosphate synthetase I(CPS-I)in the mitochondria.N-Acetyl-L-glutamic acid(NAG)is an important substance that activates the enzyme.N-Carbamyl-glutamate(NCG)has a similar structure to NAG.It can replace NAG.In this paper,starting from the synthesis of NCG,by improving the synthesis route and optimizing the reaction conditions,the green synthesis of NCG is realized.In addition,based on the synthesis method of NCG,explore the synthesis method of N-carbamyl-L-amino acid.At the same time,as the premise of NCG,the development and research of downstream products of L-glutamic acid is also of great significance.This article will continue to study the downstream products of L-glutamic acid to expand the application scope of L-glutamic acid.The main results in the paper are mentioned asfollows:(1)In this chapter,the synthesis route of NCG is designed,which uses glutamic acid and urea as raw materials to synthesize NCG by hydrothermal method.This route is easy to operate,without the introduction of toxic and harmful substances,and can realize the green synthesis of NCG.Through single factor experiment and response surface method to optimize the reaction conditions,it is determined that the best experimental conditions for generating NCG are reaction time 2.05 h,reaction temperature 119.83?,n(urea):n(L-glutamic acid)=2.2:1.The influence of each factor on the yield is from the largest to the smallest in the order of the amount ratio of the raw materials,reaction time,reaction temperature.The yield of NCG is 82.47% under the optimal process conditions.And according to the different solubility of NCG and main impurity sodium chloride in water,NCG was purified by washing with water and by recrystallization.The total yield of washing with water was 86.77,the purity was 90%,the total yield of recrystallization was 66%,and the purity was 95%.(2)Based on the synthesis process of NCG,the synthesis of N-acylated amino acids was preliminarily explored.Synthesize N-carbamoyl-L-valine(NCV)and N-carbamoyl--L-phenylalanine(NCP)with L-valine,L-phenylalanine and urea as raw materials,and passed.The product was purified by recrystallization and its structure was identified by HNMR.It can be seen that the synthesis method of NCG is also applicable to some N-acylated amino acids.(3)Two L-glutamic acid complexes were synthesized with L-glutamic acid as ligand and copper acetate and zinc acetate as metal sources.Single crystals of the two complexes were obtained by solvent volatilization,and X single crystal diffraction was used.Determine its structure.Among them,copper L-glutamate has a five-coordinate triangular bipyramid configuration,and zinc L-glutamate has a six-coordinate octahedral configuration.(4)The antioxidant and antibacterial activities of N-carbamoyl-L-amino acid and L-glutamic acid metal complex were studied.Superoxide anion free radicals,hydroxyl free radicals and DPPH free radicals were selected to compare the antioxidant capacity of these three substances.Then the antibacterial effects of different concentrations of NCG and N-carbamoyl-L-amino acid on Escherichia coli and Staphylococcus aureus were tested.When the concentration is 3mg/ml,NCG,NCP,NCV,Copper L-glutamate and L-glutamate zinc complex have 58.15%,25.10%,19.8%,61.92% and 77.46% of superoxide anion radical scavenging rate respectively;free to hydroxyl.The scavenging rates of the radicals reached8.77%,2.17%,6.88%,50.97% and 57.11%;the scavenging rates of DPPH free radicals were6.09%,4.06%,2.06%,13.11% and 26.94%,respectively. |
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