Study On Synthesis And Physiological Function Of N-carbamoyl-glutamate

N-Carbamyl-glutamate(NCG) were designed and synthesized withglutamic acid in this thesis. Secondly, through molecular biology method tostudy influencing mechanism of physiological function of sows. Finally, Toevaluate safety performance as feed additive via toxicity experiment.Themain contents of this thesis include following:In experiment 1: NCG was prepared from glutamic acid,potassiumcyanate through nucleophilic substitution,reduction,basic hydrolysis andrecrystallization in 87% yield (purity≧92.0%).In this paper, the deficiencies in the product process of NCG wereimproved via exploratory and parallel experiments. Organic synthesismethod was used to synthetic NCG. Product was simple and easy to get, lessby-products, shorten the reaction time. The process was simplified and thecost was reduced by using Hydantoic acid as catalyst. And then, variousreaction conditions, such as material ratio, temperature, amount ofconcentrated hydrochloric acid and so on, were discussed to reduce thebinary substituted by-products, so the process of separation and puritycould be avoided. Yield increased by 20%. And also target compound wassynthesized from hydrolysis in alkaline system to avoid producinghydrocyanic acid from potential safety hazard. The by-products wasseparated, and then characterized by NMR and LC/MS. It's found that thestructures of target product was confirmed. Now,The synthesis process hasnot been reported also no large-scale production in China.In experiment 2:Pig as an animal model in this thesis. Study ARG andthe NCG on the production performance of pregnant sows. Gene VEGF-A,PLGF and eNOS in placenta may play an important role in molecularmechanism of nutrient supply for pregnant sows. Proposed"The effect ofplacental blood supply of the sow via ARG-NO-VEGF pathway"hypothesis.Twenty-seven Landrace×Large White sows with similar body weight (BW)and parity at d (93±1) of gestation were assigned randomly into 3 groups:control group(n=9), ARG group(n=9), NCG group(n=9), and fed with thefollowing diets: a control diet, and the control diet supplemented with 1%ARG or 0.1% NCG. Record all kinds of production data. Placenta chorioallantoic membrane tissue collected immediately after birthed topreserved in RNA stabilizer for mRNA analysis of vascular endothelialgrowth factor a (VEGFA),placenta growth factor (PLGF) and endothelialnitric oxide synthetase (eNOS) by real time-PCR. Result shows:①piglet birth weight increased in ARG and NCG sows compared tocontrol sows (P <0.05) and litter size death decreased significantly(P<0.05).litter size live increased tend in ARG sows compared to control sows(0.05<P<0.1).②NO, VEGF-A, NOS concentrations were higher in ARG and NCG sowsthan in control in serum.③ARG and NCG groups enhanced VEGF-A,PLGF,eNOS mRNAexpression in placenta. Dietary ARG and NCG supplementation to improvelitter size and fetal survival might relate to enhance NO, VEGF-A, NOSconcentrations of sows serum effectively and elevated VEGF, PLGF andeNOS gene expression in placental surface vessels rich, melioratedplacental vascular function, and promote the supply of nutrients.In experiment 3: 50 Kunming mices of clean grade were randomlydivided into five groups. Kunming mice were fed NCG by oral ashigh-dose,middle-dose and low-dose group at 2500 mg / kg ? BW,1250mg/kg·BW and 625 mg/kg·BW separately. It set up a positive control(cyclophosphamide;CTX, 40 mg/kg) and a Negative control(Distilled water).Mice Sperm abnormality experiment were started by conventional methods(GB15193.7-2003). Given by continuous oral test substance 5 days, Countfrom the first test substance given to the first 35 days animals weresacrificed by cervical dislocation, The bilateral epididymis were productedslices. Mice Sperm abnormalities rate were calculated during 1000 Spermsper animal. Result shows NCG has no effect on sperm, and on thereproductive cells without genetic toxicity.