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Yuan J, Yang C, Cao J, Zhang L. Effects of Low Temperature-Ultrasound-Papain (LTUP) Combined Treatments on Purine Removal from Pork Loin and Its Influence on Meat Quality and Nutritional Value. Foods 2024; 13:1215. [PMID: 38672887 PMCID: PMC11048761 DOI: 10.3390/foods13081215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/06/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
A combined pretreatment method of "low temperature-ultrasound-papain" (LTUP) was proposed to remove the purine of pork loins. Compared with untreated pork loin, under optimal conditions (temperature 58 °C, ultrasound density 100 W/cm2, and papain concentration 0.085%), the purine removal rate of treated pork loin could reach 59.29 ± 1.39%. The meat quality of pork loin treated with the LTUP method such as hardness and chewiness decreased by 58.37% and 64.38%, respectively, and the in vitro protein digestibility was increased by 19.64%; the cooking loss was decreased by 15.45%, compared with the simulated household blanching process (HT). In view of the high purine removal rate, the losses of free amino acids and soluble peptides were acceptable and reasonable. SEM and LF-NMR results showed that low temperature and ultrasound combined with papain treatment opened a channel for purine transfer and promoted purine dissolution by affecting the protein structure of pork loin. In addition, the migration of water within the muscle tissue was also related to purine removal. In summary, LTUP is recommended as an efficient and green way for the meat industry to remove purine.
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Affiliation(s)
- Jiaojiao Yuan
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China; (J.Y.); (C.Y.); (J.C.)
| | - Cheng Yang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China; (J.Y.); (C.Y.); (J.C.)
| | - Jialing Cao
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China; (J.Y.); (C.Y.); (J.C.)
| | - Lianfu Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China; (J.Y.); (C.Y.); (J.C.)
- College of Food, Shihezi University, Beisi Road, Shihezi 832003, China
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Effect on purine releasement of Lentinus edodes by different food processing techniques. Food Chem X 2022; 13:100260. [PMID: 35498996 PMCID: PMC9040045 DOI: 10.1016/j.fochx.2022.100260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 11/24/2022] Open
Abstract
Freeze-drying could notably decrease the purine release from lentinus edodes. Roast-drying reduced guanine and adenine levels in lentinus edodes. Roast-drying raised the level of strong uricogenic purine hypoxanthine in lentinus edodes. The total purine content was higher than that of raw LE after moist heating.
Lentinus edodes (LE) is very popular in the world and also considered as high purine food. However, few focuses on purine types and its change during food processing. Here, we first compared 3 drying techniques, including roast-drying, freeze-drying, sun-drying on purine contents of LE by using acidolysis and HPLC. It showed that adenine decreased significantly after roast-drying (120 °C), which may be caused by thermal damage of DNA. Total purine decreased significantly after freeze-drying, while roast-dried and sun-dried LE remained unchanged. The effect of moist heat (boiling) on LE purine were also evaluated. Total purine increased due to xanthine increasement (331.72 ± 50.07%). And purine contents transferred into boiled liquid was higher than that in boiled solid. Compared with sun-dry and roast-dry processing, freeze-drying could notably affect the purine release from LE and decrease purine contents. Therefore, freeze-drying is recommended for process techniques for hyperuricemia and gouts populations.
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Hou C, Xiao G, Amakye WK, Sun J, Xu Z, Ren J. Guidelines for purine extraction and determination in foods. FOOD FRONTIERS 2021. [DOI: 10.1002/fft2.100] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Chuanli Hou
- School of Food Science and Engineering South China University of Technology Guangzhou People's Republic of China
| | - Ganhong Xiao
- School of Food Science and Engineering South China University of Technology Guangzhou People's Republic of China
| | - William Kwame Amakye
- School of Food Science and Engineering South China University of Technology Guangzhou People's Republic of China
| | - Jing Sun
- School of Food Science and Engineering South China University of Technology Guangzhou People's Republic of China
| | - Zhenzhen Xu
- School of Food Science and Engineering South China University of Technology Guangzhou People's Republic of China
| | - Jiaoyan Ren
- School of Food Science and Engineering South China University of Technology Guangzhou People's Republic of China
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El-Newary SA, Afifi SM, Aly MS, Ahmed RF, El Gendy AENG, Abd-ElGawad AM, Farag MA, Elgamal AM, Elshamy AI. Chemical Profile of Launaea nudicaulis Ethanolic Extract and Its Antidiabetic Effect in Streptozotocin-Induced Rats. Molecules 2021; 26:1000. [PMID: 33668635 PMCID: PMC7918448 DOI: 10.3390/molecules26041000] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 02/07/2021] [Accepted: 02/07/2021] [Indexed: 11/24/2022] Open
Abstract
Launaea nudicaulis is used in folk medicine worldwide to treat several diseases. The present study aimed to assess the antidiabetic activity of L. nudicaulis ethanolic extract and its effect on diabetic complications in streptozotocin-induced hyperglycemic rats. The extract was orally administrated at 250 and 500 mg/kg/day for 5-weeks and compared to glibenclamide as a reference drug at a dose of 5 mg/kg/day. Administration of the extract exhibited a potential hypoglycemic effect manifested by a significant depletion of serum blood glucose concurrent with a significant elevation in serum insulin secretion. After 5-weeks, extract at 250 and 500 mg/kg/day decreased blood glucose levels by about 53.8 and 68.1%, respectively, compared to the initial values (p ≤ 0.05). The extract at the two dosages prevented weight loss of rats from the 2nd week till the end of the experiment, compared to diabetic control rats. The extract further exhibited marked improvement in diabetic complications including liver, kidney and testis performance, oxidative stress, and relative weight of vital organs, with respect to diabetic control. Histopathological examinations confirmed the previous biochemical analysis, where the extract showed a protective effect on the pancreas, liver, kidney, and testis that degenerated in diabetic control rats. To characterize extract composition, UPLC-ESI-qTOF-MS identified 85 chromatographic peaks belonging to flavonoids, phenolics, acyl glycerols, nitrogenous compounds, and fatty acids, with four novel phenolics reported. The potential anti-diabetic effect warrants its inclusion in further studies and or isolation of the main bioactive agent(s).
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Affiliation(s)
- Samah A. El-Newary
- Medicinal and Aromatic Plants Research Department, National Research Centre, 33 El Bohouth St., Dokki, Giza 12622, Egypt; (S.A.E.-N.); (A.E.-N.G.E.G.)
| | - Sherif M. Afifi
- Pharmacognosy Department, Faculty of Pharmacy, University of Sadat City, Sadat City 32897, Egypt;
| | - Mohamed S. Aly
- Department of Animal Reproduction and Artificial Insemination, National Research Centre, 33 El Bohouth St., Dokki, Giza 12622, Egypt;
| | - Rania F. Ahmed
- Chemistry of Natural Compounds Department, National Research Centre, 33 El Bohouth St., Dokki, Giza 12622, Egypt; (R.F.A.); (A.I.E.)
| | - Abd El-Nasser G. El Gendy
- Medicinal and Aromatic Plants Research Department, National Research Centre, 33 El Bohouth St., Dokki, Giza 12622, Egypt; (S.A.E.-N.); (A.E.-N.G.E.G.)
| | - Ahmed M. Abd-ElGawad
- Department of Botany, Faculty of Science, Mansoura University, Mansoura 35516, Egypt
| | - Mohamed A. Farag
- Pharmacognosy Department, College of Pharmacy, Cairo University, Kasr el Aini St., Cairo P.B. 11562, Egypt;
- Chemistry Department, School of Sciences & Engineering, The American University in Cairo, New Cairo 11835, Egypt
| | - Abdelbaset M. Elgamal
- Department of Chemistry of Microbial and Natural Products, 33 El-Bohouth St., Dokki, Giza 12622, Egypt
| | - Abdelsamed I. Elshamy
- Chemistry of Natural Compounds Department, National Research Centre, 33 El Bohouth St., Dokki, Giza 12622, Egypt; (R.F.A.); (A.I.E.)
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Chitty JL, Fraser JA. Purine Acquisition and Synthesis by Human Fungal Pathogens. Microorganisms 2017; 5:microorganisms5020033. [PMID: 28594372 PMCID: PMC5488104 DOI: 10.3390/microorganisms5020033] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 06/06/2017] [Accepted: 06/06/2017] [Indexed: 01/13/2023] Open
Abstract
While members of the Kingdom Fungi are found across many of the world's most hostile environments, only a limited number of species can thrive within the human host. The causative agents of the most common invasive fungal infections are Candida albicans, Aspergillus fumigatus, and Cryptococcus neoformans. During the infection process, these fungi must not only combat the host immune system while adapting to dramatic changes in temperature and pH, but also acquire sufficient nutrients to enable growth and dissemination in the host. One class of nutrients required by fungi, which is found in varying concentrations in their environmental niches and the human host, is the purines. These nitrogen-containing heterocycles are one of the most abundant organic molecules in nature and are required for roles as diverse as signal transduction, energy metabolism and DNA synthesis. The most common life-threatening fungal pathogens can degrade, salvage and synthesize de novo purines through a number of enzymatic steps that are conserved. While these enable them to adapt to the changing purine availability in the environment, only de novo purine biosynthesis is essential during infection and therefore an attractive antimycotic target.
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Affiliation(s)
- Jessica L Chitty
- Australian Infectious Diseases Research Centre, School of Chemistry & Molecular Biosciences, the University of Queensland, St Lucia, Queensland 4072, Australia.
- Institute for Molecular Bioscience, the University of Queensland, St Lucia, Queensland 4072, Australia.
| | - James A Fraser
- Australian Infectious Diseases Research Centre, School of Chemistry & Molecular Biosciences, the University of Queensland, St Lucia, Queensland 4072, Australia.
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Qu X, Sui J, Mi N, Lin H. Determination of four different purines and their content change in seafood by high-performance liquid chromatography. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2017; 97:520-525. [PMID: 27080363 DOI: 10.1002/jsfa.7755] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 04/07/2016] [Accepted: 04/08/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND Seafood is regarded as a high-purine food that may induce gout, which has attracted extensive attention concerning its safety. Therefore, the aim of this study was to develop a simple and reliable method to determine the purine content in seafood and its change during storage to offer consumers healthy diet information. RESULTS Chromatographic separation was carried out using Waters Atlantis dC18 column, and potassium phosphate monobasic solution (0.02 mol L-1 , pH 3.6) as a mobile phase. The average recovery yields of four purines were 91.5-105.0%, and relative standard deviation values were around 1.8-6.5%. Shrimp and snail contained higher amounts of purine than fish and bivalves; the livers and skins of fish contained higher amounts of purine than muscles; and the main purine varied depending on the type of seafood. Also, purine content of seafood changed during storage. CONCLUSION The purine content of seafood differed depending on species, body part and degree of freshness, which could recommend consumers a healthy diet, especially for people with hyperuricemia and gout. © 2016 Society of Chemical Industry.
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Affiliation(s)
- Xin Qu
- Food Safety Laboratory, Ocean University of China, Qingdao 26600, China
| | - Jianxin Sui
- Food Safety Laboratory, Ocean University of China, Qingdao 26600, China
| | - Nasha Mi
- Food Safety Laboratory, Ocean University of China, Qingdao 26600, China
| | - Hong Lin
- Food Safety Laboratory, Ocean University of China, Qingdao 26600, China
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Fukuuchi T, Yamaoka N, Kaneko K. Analysis of Intra- and Extracellular Levels of Purine Bases, Nucleosides, and Nucleotides in HepG2 Cells by High-performance Liquid Chromatography. ANAL SCI 2016; 31:895-901. [PMID: 26353955 DOI: 10.2116/analsci.31.895] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To evaluate cellular uptake and purine transport, we developed a high-performance liquid chromatography method for intra- and extracellular purine quantification. Our aim was to develop an effective method for simultaneously quantifying the substrate and metabolites with high sensitivity. C18 columns from different manufacturers were tested for simultaneous quantification of 22 different purine bases, nucleosides, and nucleotides. We used a YMC-Triart C18 column. The analysis conditions, including extraction solutions for the cells and cell culture medium, were optimized to achieve good quantification. Linearity, accuracy, determination limits, and recovery were assessed and showed good performance. The developed HPLC method was successfully applied to the qualitative analysis of 22 different intra- and extracellular purines, demonstrating that it is useful for studying the overall pattern of purine metabolism. This method could also be useful for evaluating metabolic dynamics of purines under a variety of stimulatory conditions of culture cells.
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Affiliation(s)
- Tomoko Fukuuchi
- The Laboratory of Biomedical and Analytical Sciences, Faculty of Pharma Sciences, Teikyo University
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Inazawa K, Sato A, Kato Y, Yamaoka N, Fukuuchi T, Yasuda M, Mawatari K, Nakagomi K, Kaneko K. Determination and profiling of purines in foods by using HPLC and LC-MS. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2015; 33:439-44. [PMID: 24940702 DOI: 10.1080/15257770.2013.865744] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Purines in food are known to raise serum uric acid levels. We determined the purine content of sweet potato and beef by high-performance liquid chromatography and liquid chromatography-mass spectrometry. The purine content of the samples was 118-1,034 μmol/100 g. The total purine content was also divided into purine bases, nucleosides, nucleotides, and nucleic acids. Our results suggest that differences in total purine content and in the ratio of purine types between vegetables and beef cause a difference in elevation of serum uric acid levels.
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Affiliation(s)
- K Inazawa
- a Faculty of Pharma Sciences, Teikyo University , Tokyo , Japan
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9
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Fukuuchi T, Morimura A, Kawatani M, Yamamoto K, Yamaoka N, Kaneko K. Characterizing substrate properties of purine-related compounds with purine metabolism enzymes for enzymatic peak-shift HPLC method. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2015; 33:445-53. [PMID: 24940703 DOI: 10.1080/15257770.2013.863333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We have extended peak-shift method for measuring purine bases to make it suitable for other purine-related compounds. We optimized the reactions of the purine metabolism enzymes 5'-nucleotidase (EC 3.1.3.5), purine nucleoside phosphorylase (PNP) (EC 2.4.2.1), xanthine oxidase (XO) (EC 1.17.3.2), urate hydroxylase (EC 1.7.3.3), adenosine deaminase (ADA) (EC 3.5.4.4), and guanine deaminase (EC 3.5.4.3) by determining their substrate specificity and reaction kinetics. These enzymes eliminate the five purine base peaks (adenine, guanine, hypoxanthine, xanthine, and uric acid) and four nucleosides (adenosine, guanosine, inosine, and xanthosine). The bases and nucleosides can be identified and accurately quantified by comparing the chromatograms before and after treatment with the enzymes. Elimination of the individual purine compound peaks was complete in a few minutes. However, when there were multiple substrates, such as for XO, and when the metabolites were purine compounds, such as for PNP and ADA, it took longer to eliminate the peaks. The optimum reaction conditions for the peak-shift assay methods were an assay mixture containing the substrate (10 μL, 0.1 mg/mL), the combined enzyme solution (10 μL each, optimum concentration), and 50 mM sodium phosphate (up to 120 μL, pH 7.4). The mixture was incubated for 60 minutes at 37°C. This method should be suitable for determining the purine content of a variety of samples, without interference from impurities.
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Affiliation(s)
- T Fukuuchi
- a Laboratory of Biomedical and Analytical Sciences, Faculty of Pharma Sciences , Teikyo University , Itabashi , Tokyo , Japan
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10
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Determination of purine contents in different parts of pork and beef by high performance liquid chromatography. Food Chem 2014; 170:303-7. [PMID: 25306349 DOI: 10.1016/j.foodchem.2014.08.059] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 05/02/2014] [Accepted: 08/13/2014] [Indexed: 01/03/2023]
Abstract
Determination of adenine, hypoxanthine, guanine and xanthine in different parts of pork and beef using high performance liquid chromatography was described. Chromatographic separation was carried out on Waters Atlantis T3 column (4.6 mm × 250 mm × 5 μm) with column temperature at 30 °C. The mobile phase contained 99% 10.0 mmol/L ammonium formate solution at pH 3.6 and 1.0% methanol. Chromatography was achieved at a flow rate of 1.0 mL/min and detection wavelength at 254 nm. The results indicated that total purine amounts in pork rump and beef sirloin were higher than those in other parts (P<0.05). The principal purine bases were hypoxanthine and adenine, and hypoxanthine content was the most highest in all samples (P<0.05). As pork rump and beef sirloin contain considerable amounts of total purine and uricogenic purine base, we suggest that excess consumption of them be avoid, whereas pork loin chop and beef rib eye are more suitable for a low-purine diet.
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Dudley E, Bond L. Mass spectrometry analysis of nucleosides and nucleotides. MASS SPECTROMETRY REVIEWS 2014; 33:302-31. [PMID: 24285362 DOI: 10.1002/mas.21388] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 05/03/2013] [Accepted: 05/03/2013] [Indexed: 05/12/2023]
Abstract
Mass spectrometry has been widely utilised in the study of nucleobases, nucleosides and nucleotides as components of nucleic acids and as bioactive metabolites in their own right. In this review, the application of mass spectrometry to such analysis is overviewed in relation to various aspects regarding the analytical mass spectrometric and chromatographic techniques applied and also the various applications of such analysis.
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Affiliation(s)
- Ed Dudley
- Institute of Mass Spectrometry, College of Medicine, Swansea University, Singleton Park, Swansea, SA2 8PP, UK
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Roy L, Harrell CC, Ryan AS, Thorsteinsson T, Sancilio FD. Development and Validation of a Single HPLC Method for Analysis of Purines in Fish Oil Supplements. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/fns.2013.412160] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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13
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Yamaoka N, Inazawa K, Inagawa S, Yasuda M, Mawatari K, Nakagomi K, Fujimori S, Yamada Y, Kaneko K. Simultaneous determination of purine and pyrimidine metabolites in HPRT-deficient cell lines. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2012; 30:1256-9. [PMID: 22132983 DOI: 10.1080/15257770.2011.616565] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Genetic mutations in the purine salvage enzyme, hypoxanthine-guanine phosphoribosyltransferase (HPRT), are known to cause Lesch-Nyhan syndrome and Kelley-Seegmiller syndrome. In patients, purine metabolism is different from that of normal persons. We have previously developed a method for simultaneously determining the concentration of purine and pyrimidine nucleosides and nucleotides. This system was applied to determine the concentrations of nucleosides and nucleotides in HPRT-deficient cell lines. The amount of inosine 5'-monophosphate (IMP) was different in Lesch-Nyhan syndrome, Kelley-Seegmiller syndrome, and control cell lines. The difference in the amount of IMP confirmed the mutation of the enzyme.
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Affiliation(s)
- N Yamaoka
- Department of Analytical Chemistry, School of Pharmaceutical Sciences, Teikyo University, Kanagawa, Japan.
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Fluorescence and Electrochemical Recognition of Nucleosides and DNA by A Novel Luminescent Bioprobe Eu(lll) -TNB. J Fluoresc 2012; 22:971-92. [DOI: 10.1007/s10895-011-1036-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Accepted: 12/28/2011] [Indexed: 12/11/2022]
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15
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Simultaneous determination of nucleosides and nucleotides in dietary foods and beverages using ion-pairing liquid chromatography-electrospray ionization-mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:2054-60. [PMID: 20594924 DOI: 10.1016/j.jchromb.2010.05.044] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 05/29/2010] [Accepted: 05/31/2010] [Indexed: 11/21/2022]
Abstract
A method using ion-pairing liquid chromatography-electrospray ionization (ESI)-mass spectrometry (MS) was developed for the simultaneous determination of 23 types of purine or pyrimidine nucleosides and nucleotides in dietary foods and beverages. Dihexylammonium acetate (DHAA) was used as an ion-pairing agent and an ultra performance liquid chromatography (UPLC) system with a reversed-phase column and a gradient program was employed for the separation of nucleosides and nucleotides. Positive-ion ESI-MS was applied for the detection of nucleosides, and negative-ion ESI-MS was used for nucleotides. Lower limits of quantitation ranged from 0.02 micromol/L (UMP and AMP) to 1.3 micromol/L (CDP). The present method was validated, and sufficient reproducibility and accuracy was obtained for the quantitative measurement of the 23 types of nucleosides and nucleotides. The method was subsequently applied to their determination in a range of Japanese foods and beverages that are considered to contain significant amounts of umami flavor compounds. Because dietary purine nucleosides and nucleotides are known to be related to hyperuricemia and gout, the determination of their concentrations in dietary foods is useful for both evaluating umami flavor and assessing the effects of dietary food on purine metabolism.
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