NMR and MS Analysis of Decomposition Compounds Produced from N-Acetyl-L-glutamine at Low pH
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- 作者：Marti Mamula Bergana ; Jason D. Holton ; Irene L. Reyzer ; Maureen K. Snowden ; Jeffrey H. Baxter ; and Vickie L. Pound
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2000
- 出版时间：December 2000
- 年：2000
- 卷：48
- 期：12
- 页码：6003 - 6010
- 全文大小：94K
- 年卷期：v.48,no.12(December 2000)
- ISSN：1520-5118
文摘
N-Acetyl-<FONT SIZE="-1">L-glutamine decomposition products glutamine, glutamic acid, pyroglutamic acid, N-acetylglutamic acid, and a novel compound, N-(2,6-dioxo-3-piperidinyl) acetamide, have beenidentified by NMR and MS techniques. N-Acetylglutamine, a modified amino acid, offers greaterchemical stability than glutamine in conditions that are experienced during typical sterilizationand shelf storage of liquid nutritionals. However, to support safety and stability studies, potentialdecomposition products of N-acetyl-L-glutamine needed to be identified. Therefore, atypically harshconditions were used; an unbuffered (pH <3) 1 mg/mL water solution of N-acetyl-L-glutamine washeated to 100 
f">C for 3 h. One-dimensional proton and proton-decoupled carbon-13 NMR andelectrospray LC-MS/MS techniques were employed to identify the molecular structures of thegenerated N-acetyl-L-glutamine decomposition products. Additionally, DEPT and two-dimensionalNMR techniques TOCSY, GMQCOSY, GHSQC, and GHMBC were employed to derive the finalstructure of the acetamide.Keywords: Functional foods; NMR; LC-MS; HPLC; glutamine; N-acetylglutamine; decompositionproducts; stability
f">C for 3 h. One-dimensional proton and proton-decoupled carbon-13 NMR andelectrospray LC-MS/MS techniques were employed to identify the molecular structures of thegenerated N-acetyl-L-glutamine decomposition products. Additionally, DEPT and two-dimensionalNMR techniques TOCSY, GMQCOSY, GHSQC, and GHMBC were employed to derive the finalstructure of the acetamide.Keywords: Functional foods; NMR; LC-MS; HPLC; glutamine; N-acetylglutamine; decompositionproducts; stability