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LC/ MS-MS analysis of tea

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https://www.readbyqxmd.com/read/29759220/determination-of-perchlorate-from-tea-leaves-using-quaternary-ammonium-modified-magnetic-carboxyl-carbon-nanotubes-followed-by-liquid-chromatography-tandem-quadrupole-mass-spectrometry
#1
Yong-Gang Zhao, Yun Zhang, Feng-Lian Wang, Jian Zhou, Qi-Ming Zhao, Xiu-Qiong Zeng, Mei-Qin Hu, Mi-Cong Jin, Yan Zhu
The novel quaternary ammonium modified magnetic carboxyl-carbon nanotubes (QA-Mag-CCNTs) have been synthesised and characterized. QA-Mag-CCNTs were applied in magnetic dispersive solid phase extraction (Mag-dSPE) for preconcentration of perchlorate from tea leaves prior to liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) analysis. The Mag-dSPE procedure for preconcentration of perchlorate succeed in overcoming the flaw (containing target analyte randomly) of commercially available SPE cartridge...
August 1, 2018: Talanta
https://www.readbyqxmd.com/read/29755350/extracts-from-hypericum-hircinum-subsp-majus-exert-antifungal-activity-against-a-panel-of-sensitive-and-drug-resistant-clinical-strains
#2
Noemi Tocci, Daniele Perenzoni, Duilio Iamonico, Francesca Fava, Tobias Weil, Fulvio Mattivi
During the last two decades incidences of fungal infections dramatically increased and the often accompanying failure of available antifungal therapies represents a substantial clinical problem. The urgent need for novel antimycotics called particular attention to the study of natural products. The genus Hypericum includes many species that are used in the traditional medicine to treat pathological states like inflammations and infections caused by fungi. However, despite the diffused use of Hypericum -based products the antifungal potential of the genus is still poorly investigated...
2018: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/29709169/influence-of-storage-on-the-stability-of-toxic-pyrrolizidine-alkaloids-and-their-n-oxides-in-peppermint-tea-hay-and-honey
#3
Florian Kaltner, Michael Rychlik, Manfred Gareis, Christoph Gottschalk
1,2-dehydropyrrolizidine alkaloids (PA) and PA-N-oxides (PANO) are phytotoxins, which presumably occur in more than 6000 plant species worldwide. Plants containing PA/PANO are responsible for various food and feed poisonings recorded for decades. Main reasons of exposition of consumers and livestock are contaminations of food and animal feed with parts, seeds, pollen or nectar of PA containing plants. Concerning stability, effects of processing on PA were mainly investigated in the past. The current study examined the behavior of PA/PANO in unprocessed matrices peppermint tea, hay and honey during storage...
April 30, 2018: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29534564/novel-theaflavin-type-chlorogenic-acid-derivatives-identified-in-black-tea
#4
Shuwei Zhang, Chun Yang, Emmanuel Idehen, Shi Lei, Lishuang Lv, Shengmin Sang
Black tea consumption has been associated with many health benefits including the prevention of cancer and heart disease. However, the chemical composition of black tea has not been fully explored. Most studies have examined different interactions between the four major tea catechins, and few studies have examined the interaction between catechins and other components in tea. In the present study, we tested our hypothesis that the ortho-dihydroxyl structure of chlorogenic acid (CGA) could react with the vic-trihydroxy structure of (-)-epigallocatechin 3-gallate (EGCG) and (-)-epigallocatechin (EGC) to generate theaflavin-type of compounds during black tea fermentation...
March 13, 2018: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29510082/validation-and-application-of-a-lc-ms-ms-method-for-the-determination-of-cyclic-oligomers-originating-from-polyamide-6-and-polyamide-66-in-food-simulant
#5
Oliver Kappenstein, Ingo Ebner, Carina Förster, Stephan Richter, Jürgen Weyer, Karla Pfaff, Andreas Luch
Polyamides (PA) are used in the production of various food contact materials (FCMs) and articles such as kitchen utensils and packaging material. Cyclic oligomers have been identified as potential migrants from PA. This study describes the development, validation and application of a multi-oligomer analytical method based on liquid chromatography-tandem electrospray mass spectrometry (LC-ESI-MS/MS) for the identification and quantification of eight cyclic oligomers of PA 6 and four PA 66 migrating from FCMs into food simulant B (3% acetic acid) and beverages...
March 6, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29495365/black-tea-samples-origin-discrimination-using-analytical-investigations-of-secondary-metabolites-antiradical-scavenging-activity-and-chemometric-approach
#6
Wojciech Koch, Wirginia Kukula-Koch, Łukasz Komsta
A comprehensive study on the composition and antioxidant properties of black tea samples with a chemometric approach was performed via LC-ESI-Q-TOF-MS, DPPH radical scavenging assay, and Folin-Ciocalteu assay (TPC). Marked differences between the teas from seven different countries (China, India, Iran, Japan, Kenya, Nepal, Sri Lanka) were shown. The Indian samples demonstrated the highest total catechin content (184.8 mg/100 mL), the largest TPC and DPPH scavenging potential (58.2 mg/100 mL and 84.5%, respectively)...
February 26, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29471392/effects-of-fermentation-on-the-hemolytic-activity-and-degradation-of-camellia-oleifera-saponins-by-lactobacillus-crustorum-and-bacillus-subtilis
#7
Bingjun Qian, Lirong Yin, Xiaomin Yao, Yaoguang Zhong, Juan Gui, Feifeng Lu, Fuming Zhang, Jianhua Zhang
The saponins, as components of tea seed meal, are undesirable hemolytic components and should be degraded for reducing their hemolytic activity in order to be used in animal feed. In this study, β-glucuronidase was verified to be a potent hydrolase of tea seed saponins to reduce their hemolytic activity and a β-glucuronidase-producing Lactobacillus crustorum strain was screened from raw bovine milk. Next, solid-state fermentation with the isolated L. crustorum and a Bacillus subtilis natto strain, which can produce cellulase and hence improve the fermentation performance of tea seed meal, was carried out for detoxification of tea seed meal...
April 1, 2018: FEMS Microbiology Letters
https://www.readbyqxmd.com/read/29317677/isolation-and-characterization-of-key-genes-that-promote-flavonoid-accumulation-in-purple-leaf-tea-camellia-sinensis-l
#8
Xiujuan He, Xuecheng Zhao, Liping Gao, Xingxing Shi, Xinlong Dai, Yajun Liu, Tao Xia, Yunsheng Wang
There were several high concentrations of flavonoid components in tea leaves that present health benefits. A novel purple-leaf tea variety, 'Mooma1', was obtained from the natural hybrid population of Longjing 43 variety. The buds and young leaves of 'Mooma1' were displayed in bright red. HPLC and LC-MS analysis showed that anthocyanins and O-Glycosylated flavonols were remarkably accumulated in the leaves of 'Mooma1', while the total amount of catechins in purple-leaf leaves was slightly decreased compared with the control...
January 9, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29232949/antioxidative-flavan-3-ol-dimers-from-the-leaves-of-camellia-fangchengensis
#9
Xiu-Hua Meng, Chang Liu, Rong Fan, Li-Fang Zhu, Shi-Xiong Yang, Hong-Tao Zhu, Dong Wang, Chong-Ren Yang, Ying-Jun Zhang
Camellia fangchengensis Liang et Zhong, belonging to the genus Camellia sect. Thea (Theaceae), is an endemic tea species to the south and southwest areas of Guangxi province, People's Republic of China. Known as a wild tea plant, the leaves have been used for producing green tea or black tea by the local people of its growing area. HPLC and LC-MS analysis showed the leaves contain oligomeric catechins as major phenolic components. Further detailed phytochemical study led to the identification of five flavan-3-ol dimers (1-5) including two new ones, fangchengbisflavans A (1) and B (2) from the leaves of C...
January 10, 2018: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29219744/n-nitrosamines-migrating-from-food-contact-materials-into-food-simulants-analysis-and-quantification-by-means-of-hplc-apci-ms-ms
#10
Friederike Kühne, Oliver Kappenstein, Samira Straβgütl, Florian Weese, Jürgen Weyer, Karla Pfaff, Andreas Luch
It was the aim of the work described here to develop a validated analytical method for the determination of N-nitrosamines in food simulants. Here, we present the validation of a liquid chromatography-atmospheric pressure chemical ionisation-tandem mass spectrometry method for the determination of 13 N-nitrosamines in the food simulants deionised water, 3% acetic acid and 10% ethanol. Method validation encompassed linearity, LOD, LOQ, recovery, precision and stability of the N-nitrosamines. The method was found to be sufficiently rugged and suitable for routine analysis...
January 19, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29196011/investigation-of-epigallocatechin-3-o-caffeoate-and-epigallocatechin-3-o-p-coumaroate-in-tea-leaves-by-lc-ms-ms-analysis
#11
Masahiro Umehara, Koji Yanae, Hiroko Maruki-Uchida, Masahiko Sai
(-)-Epigallocatechin-3-O-gallate (EGCG), the major catechin present in green tea, exhibits potent antioxidant activity. We thereby investigated the presence of unknown components bearing the (-)-epigallocatechin (EGC) moiety in fresh tea leaf samples. Initially, liquid chromatography tandem mass spectrometry (LC-MS/MS) was employed to examine fresh tea leaves of the Yabukita, the most popular tea cultivar in Japan, which suggested the presence of the EGC phenylpropanoid derivatives, (-)-epigallocatechin-3-O-p-coumaroate (EGCpCA) and (-)-epigallocatechin-3-O-caffeoate (EGCCA)...
December 2017: Food Research International
https://www.readbyqxmd.com/read/29068686/multimycotoxin-lc-ms-ms-analysis-in-tea-beverages-after-dispersive-liquid-liquid-microextraction-dllme
#12
Noelia Pallarés, Guillermina Font, Jordi Mañes, Emilia Ferrer
The aim of the present study was to develop a multimycotoxin liquid chromatography tandem mass spectrometry (LC-MS/MS) method with a dispersive liquid-liquid microextraction procedure (DLLME) for the analysis of AFs, 3aDON, 15aDON, NIV, HT-2, T-2, ZEA, OTA, ENNs, and BEA in tea beverages and to evaluate their mycotoxin contents. The proposed method was characterized in terms of linearity, limits of detection (LODs), limits of quantification (LOQs), recoveries, repeatability (intraday precision), reproducibility (interday precision), and matrix effects to check suitability...
November 29, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29058896/comprehensive-lipidome-wide-profiling-reveals-dynamic-changes-of-tea-lipids-during-manufacturing-process-of-black-tea
#13
Jia Li, Jinjie Hua, Qinghua Zhou, Chunwang Dong, Jinjin Wang, Yuliang Deng, Haibo Yuan, Yongwen Jiang
As important biomolecules in Camellia sinensis L., lipids undergo substantial changes during black tea manufacture, which is considered to contribute to tea sensory quality. However, limited by analytical capacity, detailed lipid composition and its dynamic changes during black tea manufacture remain unclear. Herein, we performed tea lipidome profiling using high resolution liquid chromatography coupled to mass spectrometry (LC-MS), which allows simultaneous and robust analysis of 192 individual lipid species in black tea, covering 17 (sub)classes...
November 22, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28982053/phosphate-stresses-affect-ionome-and-metabolome-in-tea-plants
#14
Zhaotang Ding, Sisi Jia, Yu Wang, Jun Xiao, Yinfei Zhang
In order to study the response of tea plants to P stress, we conducted the ionomic and metabolomic analysis by ICP-OES, GC-MS and LC-MS. The results demonstrated that P was antagonistic with S, and was cooperative with Cu, Zn, Mn and Fe under P-deficiency. However, P was antagonistic with Mn, Fe and S, and was cooperative with Cu and Zn under P-excess. Moreover, P-deficiency or excess reduced the syntheses of flavonoids and phosphorylated metabolites. P-deficiency decreased the amount of glutamate and increased the content of glutamine, while P-excess decreased the content of glutamine...
September 14, 2017: Plant Physiology and Biochemistry: PPB
https://www.readbyqxmd.com/read/28882039/metabolic-profiling-on-alternaria-toxins-and-components-of-xinjiang-jujubes-incubated-with-pathogenic-alternaria-alternata-and-alternaria-tenuissima-via-orbitrap-high-resolution-mass-spectrometry
#15
Dongqiang Hu, Yingying Fan, Yanglan Tan, Ye Tian, Na Liu, Lan Wang, Duoyong Zhao, Cheng Wang, Aibo Wu
Xinjiang jujubes (Zizyphus rhamnaceae) are important agro-economical foods with the highest planting area and yields in China; however, black spot disease and contaminated Alternaria toxins have unfortunately caused a decline or loss of jujube nutritional quality in recent years. In this study, we used ultrahigh-performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry to profile both Alternaria toxins and components in three representative Xinjiang jujubes, Hami Huang, Hetian Jun, and Ruoqiang Hui...
September 27, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28821789/isolation-characterization-and-toxicological-potential-of-alternaria-mycotoxins-tea-aoh-and-ame-in-different-alternaria-species-from-various-regions-of-india
#16
Mukesh Meena, Prashant Swapnil, R S Upadhyay
Alternaria species produce various sorts of toxic metabolites during their active growth and causes severe diseases in many plants by limiting their productivity. These toxic metabolites incorporate various mycotoxins comprising of dibenzo-α-pyrone and some tetramic acid derivatives. In this study, we have screened out total 48 isolates of Alternaria from different plants belonging to different locations in India, on the basis of their pathogenic nature. Pathogenicity testing of these 48 strains on susceptible tomato variety (CO-3) showed 27...
August 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28388787/antidiabetic-activities-of-an-lc-ms-fingerprinted-aqueous-extract-of-fagonia-cretica-l-in-preclinical-models
#17
Imran Nazir, Nisar Ur Rahman, Zunaira Alvi, M Hafizur Rahman, Jandirk Sendker, Tao Zhang, Neil Frankish, Helen Sheridan
Diabetes mellitus is a chronic disease and one of the most important public health challenges facing mankind. Fagonia cretica is a medicinal plant used widely in the Punjab in Pakistan. A recent survey has demonstrated that traditional healers and herbalists frequently use this plant to treat diabetes. In the current study, the traditional medicine was prepared as a tea, and the profile of the main metabolites present in the traditional medicine was analysed via LC/MS/MS. The extract was shown to contain a number of phenolic glycosides including quercetin-3-O-rutinoside, kaempferol-3-O-rutinoside, kaempferol-3-O-glycoside, kaempferol-3(6'-malonylglucoside), isorhamnetin-3-O-rutinoside, and isorhamnetin 3-(6″-malonylglucoside) in addition to two unidentified sulphonated saponins...
October 2017: Planta Medica
https://www.readbyqxmd.com/read/28317742/determination-of-hymexazol-in-26-foods-of-plant-origin-by-modified-quechers-method-and-liquid-chromatography-tandem-mass-spectrometry
#18
Zejun Jiang, Hui Li, Xiaolin Cao, Pengfei Du, Hua Shao, Fen Jin, Maojun Jin, Jing Wang
A rapid and sensitive method based on modified QuEChERS for hymexazol determination in 26 plant-derived foods using liquid chromatography tandem-mass spectrometry (LC-MS/MS) was developed. Variables affecting the separation (LC column, mobile phase additives) and clean-up effects of various dispersive phases, such as PSA, C18, GCB, MWCNTs, PEP-2, Al2O3, Florisil, and PVPP were evaluated. The method was validated using 26 matrices at spiked levels of 0.01 or 0.02, 0.05, 0.1, and 0.5mg/kg (0.05, 0.2, 0.5, and 1...
August 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28300023/optimization-and-validation-of-a-residue-analysis-method-for-glyphosate-glufosinate-and-their-metabolites-in-plant-matrixes-by-liquid-chromatography-with-tandem-mass-spectrometry
#19
Dasharath P Oulkar, Sandip Hingmire, Arnab Goon, Manjusha Jadhav, Bharat Ugare, Ahammed Shabeer Thekkumpurath, Kaushik Banerjee
A sensitive and accurate LC with tandem MS (MS/MS)-based method was developed and validated for the analysis of the herbicide glyphosate, its metabolite aminomethylphosphonic acid (AMPA), and glufosinate after derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl) in various plant matrixes. The method also covers direct analysis of the glufosinate metabolites 3-methylphosphinicopropionic acid (3-MPPA) and N-acetyl-glufosinate (NAG). The homogenized samples were extracted with 0.1% formic acid in water-dichloromethane (50 + 50)...
May 1, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28183283/comparative-proteomics-analysis-of-teleost-intermuscular-bones-and-ribs-provides-insight-into-their-development
#20
Chun-Hong Nie, Shi-Ming Wan, Tea Tomljanovic, Tomislav Treer, Chung-Der Hsiao, Wei-Min Wang, Ze-Xia Gao
BACKGROUND: Intermuscular bones (IBs) and ribs both are a part of skeletal system in teleosts, but with different developing process. The chemical composition of fish IBs and ribs as well as the underlying mechanism about their development have not been investigated. In the present study, histological structures showed that one bone cavity containing osteoclasts were existed in ribs, but not in IBs of Megalobrama amblycephala. We constructed the first proteomics map for fish bones including IBs and ribs, and identified the differentially expressed proteins between IBs and ribs through iTRAQ LC-MS/MS proteomic analysis...
February 10, 2017: BMC Genomics
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