High-performance liquid chromatography (HPLC) analysis was used for identification of two problematic ureides, asparagine and citrulline. We report here a technique that takes advantage of the predictable delay in retention time of the co-asparagine/citrulline peak to enable both qualitative and quantitative analysis of asparagine and citrulline using the Platinum EPS reverse-phase C18 column (Alltech Associates). Asparagine alone is eluted earlier than citrulline alone, but when both of them are present in biological samples they may co-elute. HPLC retention times for asparagine and citrulline were influenced by other ureides in the mixture. We found that at various asparagines and citrulline ratios [= 3:1, 1:1, and 1:3; corresponding to 75:25, 50:50, and 25:75 (microMol ml(-1)/microMol ml(-1))], the resulting peak exhibited different retention times. Adjustment of ureide ratios as internal standards enables peak identification and quantification. Both chemicals were quantified in xylem sap samples of pecan [Carya illinoinensis (Wangenh.) K. Koch] trees. Analysis revealed that tree nickel nutrition status affects relative concentrations of Urea Cycle intermediates, asparagine and citrulline, present in sap. Consequently, we concluded that the HPLC methods are presented to enable qualitative and quantitative analysis of these metabolically important ureides.
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J Trace Elem Med Biol
December 2024
Department of Laboratory Science, Research and Development Division, Ospedale Isola Tiberina-Gemelli Isola, Rome 00186, Italy. Electronic address:
Background: Colorectal cancer (CRC) is a growing global health challenge with a multifactorial etiology encompassing genetic susceptibility, nutrition, and inflammation in the bowel.
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Foods
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TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Material Medical Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
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To detect the differences in types and levels of amino acids in the peripheral serum of patients with laryngeal squamous cell carcinoma and non-tumor patients, and explore their relationship with clinical parameters of laryngeal squamous cell carcinoma as well as their clinical value in diagnosis. High-performance liquid chromatography-tandem mass spectrometry(HPLC-MS) was employed to detect the serum amino acid contents and levels of 62 patients diagnosed with laryngeal carcinoma and 141 non-tumor patients at the First Affiliated Hospital of Jinzhou Medical University between September 2018 and February 2021. The study compared the differences in 22 non-essential and essential amino acids found in the serum between the experimental group and the control group.
View Article and Find Full Text PDFMetabolites
July 2024
Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Szpitalna Str. 27/33, 60-572 Poznań, Poland.
Patients with phenylketonuria (PKU) must restrict their intake of phenylalanine, which can also affect the levels of other essential and non-essential amino acids due to inadequate supply. Therefore, our objective was to assess amino acids in serum samples from 20 PKU patients and compare them with results from 51 healthy subjects. A sample analysis was conducted using liquid chromatography-tandem mass spectrometry.
View Article and Find Full Text PDFAmino Acids
January 2024
Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
By affecting the ovarian pool of follicles and their enclosed oocytes, heat stress has an impact on dairy cow fertility. This study aimed to determine how heat shock (HS) during in vitro maturation affected the ability of the bovine cumulus-oocyte complexes (COCs) to develop, as well as their metabolism of amino acids (AAs). In this study, COCs were in vitro matured for 23 h at 38.
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