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Simultaneous determination of amino acids in different teas using supercritical fluid chromatography coupled with single quadrupole mass spectrometry

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Journal of Pharmaceutical Analysis 2019年第4期9卷 254-258页

作者： Yang Huang Tiejie Wang Marianne Fillet Jacques Crommen Zhengjin Jiang Institute of Pharmaceutical Analysis College of Pharmacy Jinan University Guangzhou 510632 China Shenzhen Institute for Drug Control Shenzhen China Department of Pharmaceutics State Key Laboratory of Natural Medicines China Pharmaceutical University Nanjing China Laboratory for the Analysis of Medicine Department of Pharmaceutical Sciences CIRM University of Liege CHU B36 B-4000 Liege Belgium

Tea is a widely consumed beverage and has many important physiological properties and potential health benefits. In this study, a novel method based on supercritical fluid chromatography coupled with mass spectrometry (SFC-MS) was developed to simultaneously determine 11 amino acids in different types of tea (green teas, Oolong tea, black tea and Pu-erh tea). The separation conditions for the analysis of the selected amino acids including the column type, temperature and backpressure as well as the type of additive, were carefully optimized. The best separation of the 11 amino acids was obtained by adding water (5%, v/v) and trifluoroacetic acid (0.4%, v/v) to the organic modifier (methanol). Finally, the developed SFC-MS method was fully validated and successfully applied to the determination of these amino acids in six different tea samples. Good linearity (r ≥ 0.993), precision (RSDs≤ 2.99%), accuracy (91.95%-107.09%) as well as good sample stability were observed. The limits of detection ranged from 1.42 to 14.69 ng/mL, while the limits of quantification were between 4.53 and 47.0 ng/mL. The results indicate that the contents of the 11 amino acids in the six different tea samples are greatly influenced by the degree of fermentation. The proposed SFC-MS method shows a great potential for further investigation of tea varieties.

关键词： Amino acids Teas Supercritical fluid chromatography with single quadrupole mass spectrometry (SFCMS)

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Optimization of Gas Chromatography-electron Ionization-tandem Mass spectrometry for Determining Toxic Non-ortho Polychlorinated Biphenyls in Breast Milk

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Biomedical and Environmental Sciences 2020年第1期33卷 58-61页

作者： Iva Simic Gordana Jovanovic Snjezana Herceg Romanic Darija Klincic Marijana Matek Saric Aleksandar Popovic Institute for Medical Research and Occupational Health Ksaverska cesta 2PO Box 29110001 ZagrebCroatia Institute of Physics Belgrade National Institute of the Republic of SerbiaUniversity of BelgradePregrevica 11811080 BelgradeSerbia Department of Health Studies University of ZadarSplitska 123000 ZadarCroatia Faculty of Chemistry University of BelgradeStudentski trg 12-1611000 BelgradeSerbia

One of the most commonly used non-invasive methods for assessing human exposure to pollution is the analysis of human milk.Human milk analyses help estimate the exposure of infants[1].This is why breast milk is receives scientific interest,and various methods for determining different pollutants from the environment are being developed[2,3].

关键词： Optimization Gas Chromatography-electron Ionization-tandem Mass spectrometry Determining Toxic Non-ortho Polychlorinated Biphenyls Breast Milk

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Gas chromatography/mass spectrometry based metabolomic study in a murine model of irritable bowel syndrome

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World Journal of Gastroenterology 2018年第8期24卷 894-904页

作者： Lei-Min Yu Ke-Jia Zhao Shuang-Shuang Wang Xi Wang Bin Lu Department of Gastroenterology First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310006Zhejiang ProvinceChina First Clinical Medical College of Zhejiang Chinese Medical University Hangzhou 310053Zhejiang ProvinceChina Key Laboratory of Digestive Pathophysiology of Zhejiang Province First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina

AIM To study the role of microbial metabolites in the modulation of biochemical and physiological processes in irritable bowel syndrome(IBS).METHODS In the current study, using a metabolomic approach, we analyzed the key metabolites differentially excreted in the feces of control mice and mice with IBS, with or without Clostridium butyricum(C. butyricum) treatment. C57 BL/6 mice were divided into control, IBS, and IBS + C. butyricum groups. In the IBS and IBS + C. butyricum groups, the mice were subjected to water avoidance stress(WAS) for 1 h/d for ten days. Gas chromatography/mass spectrometry(GC-MS) together with multivariate analysis was employed to compare the fecal samples between groups. RESULTS WAS exposure established an appropriate model of IBS in mice, with symptoms of visceral hyperalgesia and diarrhea. The differences in the metabolite profiles between the control group and IBS group significantly changed with the progression of IBS(days 0, 5, 10, and 17). A total of 14 differentially excreted metabolites were identified between the control and IBS groups, and phenylethylamine was a major metabolite induced by stress. In addition, phenylalanine metabolism was found to be the most relevant metabolic pathway. Between the IBS group and IBS + C. butyricum group, 10 differentially excreted metabolites were identified. Among these, pantothenate and coenzyme A(Co A) biosynthesis metabolites, as well as steroid hormone biosynthesis metabolites were identified as significantly relevant metabolic pathways.CONCLUSION The metabolic profile of IBS mice is significantly altered compared to control mice. Supplementation with C. butyricum to IBS mice may provide a considerable benefit by modulating host metabolism.

关键词： Irritable bowel syndrome Metabolite Gas chromatography/mass spectrometry Clostridium butyricum

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Recent advances in mass spectrometry-based proteomics of gastric cancer

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World Journal of Gastroenterology 2016年第37期22卷 8283-8293页

作者： Changwon Kang Yejin Lee J Eugene Lee Department of Biological Sciences Korea Advanced Institute of Science and Technology Center for Bioanalysis Korea Research Institute of Standards and Science

The last decade has witnessed remarkable technological advances in mass spectrometry-based proteomics. The development of proteomics techniques has enabled the reliable analysis of complex proteomes, leading to the identification and quantification of thousands of proteins in gastric cancer cells, tissues, and sera. This quantitative information has been used to profile the anomalies in gastric cancer and provide insights into the pathogenic mechanism of the disease. In this review, we mainly focus on the advances in mass spectrometry and quantitative proteomics that were achieved in the last five years and how these up-andcoming technologies are employed to track biochemical changes in gastric cancer cells. We conclude by presenting a perspective on quantitative proteomics and its future applications in the clinic and translational gastric cancer research.

关键词： Gastric cancer Mass spectrometry Protein identification Proteomics Protein quantification

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Widespread arginine phosphorylation in human cells——a novel protein PTM revealed by mass spectrometry

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Science China Chemistry 2020年第3期63卷 341-346页

作者： Songsen Fu Chuan Fu Quan Zhou Rongcan Lin Han Ouyang Minning Wang Ying Sun Yan Liu Yufen Zhao Department of Chemical Biology College of Chemistry and Chemical EngineeringKey Laboratory for Chemical Biology of Fujian ProvinceXiamen UniversityXiamen 361005China School of Life Science University of DundeeDundee DD15EHUK State Key Laboratory of Proteomics Beijing Proteome Research CenterBeijing Institute of Radiation MedicineNational Center for Protein Sciences(The PHOENIX Center)Beijing 102206China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 102206China Institute of Drug Discovery Technology Ningbo UniversityNingbo 315211China

Arginine phosphorylation(p Arg)is recently discovered as a ubiquitous protein N-phosphorylation in bacteria.However,its prevalence and roles in mammalian cells remain largely unknown due to the lack of established workflow and the inherent lability of phosphoramidate(P–N)bond.Emerging evidences suggest that N-phosphorylation may extensively exist in eukaryotes and play crucial roles.We report a phosphoproteomic workflow,which allows for the first time revealing the widespread occurrence of p Arg in human cells by mass spectrometry.By virtue of this approach,we identified 152 high-confidence p Arg sites derived from 118 proteins.Remarkably,the discovered p Arg phosphorylation motif and gene ontology hint a possible cellular function of arginine phosphorylation which may regulate the favorability of propeptide convertase substrate.The obtained p Arg dataset paves a way for a better understanding of the biological functions of eukaryotic p Arg in the future.

关键词： protein arginine phosphorylation N-phosphorylation proteomics mass spectrometry human cells

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Immunopurification and Mass spectrometry Identifies Protein Phosphatase 2A （PP2A） and BIN2/GSK3 as Regulators of AKS Transcription Factors in Arabidopsis

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Molecular Plant 2017年第2期10卷 345-348页

作者： Bu, Shuo-Lei Liu, Chao Liu, Ning Zhao, Ji-Long Ai, Lian-Feng Chi, Hao Li, Kathy L. Chien, Chih-Wei Burlingame, Alma L. Zhang, Sheng-Wei Wang, Zhi-Yong Hebei Normal Univ Hebei Collaborat Innovat Ctr Cell Signaling Hebei Key Lab Mol & Cellular Biol Coll Life Sci Shijiazhuang 050024 Hebei Peoples R China Carnegie Inst Sci Dept Plant Biol 290 Panama St Stanford CA 94305 USA Chinese Acad Sci Key Lab Intelligent Informat Proc Inst Comp Technol Beijing 100190 Peoples R China Univ Calif San Francisco Dept Pharmaceut Chem San Francisco CA 94158 USA

Dear Editor ABA induces the phosphorylation of three basic helix-loop-helix （bHLH） transcription factors, called AKSs （ABA-responsive ki- nase substrates; AKS1, AKS2, and AKS3）. The unphosphorylated AKSs facilitate stomatal opening through promoting the tran- scription of genes encoding inwardly rectifying K＋ channels （Takahashi et al., 2013）. AKS1 and AKS3 are also regulators of flowering （Ito et al., 2012）. However, the kinases and phosphatases that directly control the phosphorylation status of AKSs in vivo have not been fully characterized. Here,

关键词： spectrometry Phosphatase Arabidopsis

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Serum proteomic profiling for autism using magnetic bead-assisted matrix-assisted laser desorption ionization time-of-flight mass spectrometry: a pilot study

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World Journal of Pediatrics 2018年第3期14卷 233-237页

作者： Yan-Ni Chen Hui-Ying Du Zhuo-Yue Shi Li He Yu-Ying He Duan Wang Department of Health Care Xi’an Children’s HospitalXi’an Jiaotong University69 XijuyuanxiangXi’an 710002China Department of Biology College of Liberal Arts and ScienceThe University of Io waIowaUSA Department of P ediatrics Shaanxi University of Chinese MedicineXianyangShannxiChina Xi’an Maternal and Child Health Hospital 73 West StreetXi’an 710002China

Background The pathogenesis of autism spectrum disorders remains elusive and currently there are no diagnostic or pre-dictive biomarkers in autism available. Proteomic profiling has been used in a wide range of neurodevelopmental disorder studies, which could produce deeper perceptions of the molecular bases behind certain disease and potentially becomes useful in discovering biomarkers in autism spectrum disorders. Methods Serum samples were collected from autistic children about 3 years old in age (n = 32) and healthy controls (n = 20) in similar age and gender. The samples were identified specific proteins that are diff erentially expressed by magnetic bead-based pre-fractionation and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF-MS). Results Eight protein peaks were significantly different in autistic children from the healthy controls (P < 0.0001). The two peaks with the most significant diff erences were 6428 and 7758 Da in size. Conclusion According to diff erences in serum protein profiles between the autistic children and healthy controls, this study identified a set of diff erentially expressed proteins those are significant for further evaluation and might function as biomark-ers in autism.

关键词： Autism Matrix-assisted laser desorption ionization time-of-fl ight mass spectrometry Proteomic profi ling Weak cation-exchange chromatography magnetic beads

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Synthesis of metallic silicide fullerenes and the characteristics thereof by mass spectrometry

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Science China(Physics,Mechanics & Astronomy) 2007年第2期50卷 215-220页

作者： CHEN YiChi GUO Liang ZHU LiQun School of Material Science and Engineering Beijing University of Aeronautics&AstronauticsBeijing 100083China

Direct current arc discharge is used for the study on the synthesis of metallo-fullerenes (MFs) to discover whether there exist metallic silicide fullerenes and silicon fullerenes. The resultant components are isolated by the multistage high-performance liquid chromatography (HPLC) and analyzed with the Time-of-Flight (TOF) mass spectrometry. Results show that there exist fullerenes such as SiC69, YSi2C64, YSi2C78, Y3Si2C78 as well as Y2Si2C90 which are structurally similar to (Y2C2)@C82.

关键词： silicide fullerene metallofullerene metallic-silicide TOF mass spectrometry

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Probing interaction of melittin with lipid membranes using liquid secondary ion mass spectrometry

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Science China Chemistry 1998年第1期41卷 77-84页

作者：武轶隋森芳 State Key Laboratory of Biomembrane and Membrane Biotechnology Department of Biological Sciences and Biotechnology Tsinghua University Beijing China Beijing Institute of Microchemistry Beijing China

The membrane insertion mechanism of toxic protein is a very active domain in the study of molecular biology, and the "anchor state" of the membrane bound protein on membrane is the key problem which it is difficult to solve with traditional methods. In the present work we first studied the "anchor state" of melittin on membrane using liquid secondary ion mass spectrometry (LSIMS) in combination with proteolysis by specific enzyme. The results show that the membrane bound melittin molecules mainly take the conformation in which the axis of α helix lies parallel to the membrane surface and the side containing Lys 7, Lys 21 and Arg 22 faces the outside of the lipid membrane. This discovery is very significant to the studies of membrane insertion mechanism. The results also indicate that the combination of mass spectrometry technique with the proteolysis by specific enzyme has provided a very new and effective method for the studies of the membrane insertion mechanism.

关键词： melittin liquid secondary ion mass spectrometry protein orientation lipid membrane.

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EGFR/cell membrane chromatography-online-high performance liquid chromatography/mass spectrometry method for screening EGFR antagonists from Radix Angelicae Pubescentis

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Science China Chemistry 2010年第11期53卷 2357-2362页

作者： SiCen Wang Meng Sun YanMin Zhang Jie Zhang LangChong He Xi An Jiao Tong Univ Sch Med Minist Educ Key Lab Environm & Genes Related Dis Xian 710061 Peoples R China

The intracellular kinase domains of the epidermal growth factor receptor(EGFR) in some tumor cells are significant targets for drug discovery.We have developed a new EGFR cell membrane chromatography(EGFR/CMC)-online-high performance liquid chromatography/mass spectrometry(HPLC/MS) method for screening anti-EGFR antagonists from medicinal herbs such as Radix Angelicae Pubescentis.In this study,the HEK293 EGFR cells with high expression of EGFR were used to prepare cell membrane stationary phase(CMSP) in the EGFR/CMC model.The retention fractions on the EGFR/CMC model were directly analyzed by combining a 10 port columns switcher with a HPLC/MS system online.As a result,osthole from Radix Angelicae Pubescentis was found to be the active component acting on EGFR like dasatinib as the control drug.There was a good relationship between their inhibiting effects on EGFR secretion and HEK293 EGFR cell growth in vitro.This new EGFR/CMC-online-HPLC/MS method can be applied for screening anti-EGFR antagonists from TCMs,for instance,Radix Angelicae Pubescentis.It will be a useful method for drug discovery with natural medicinal herbs as a leading compound resource.

关键词： EGFR cell membrane chromatography high performance liquid chromatography/mass spectrometry anti-EGFR antagonists Radix Angelicae Pubescentis

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