keyword
MENU ▼
Read by QxMD icon Read
search

LC/ MS-MS analysis of tea

keyword
https://www.readbyqxmd.com/read/29068686/multimycotoxin-lc-ms-ms-analysis-in-tea-beverages-after-dispersive-liquid-liquid-microextraction-dllme
#1
Noelia Pallarés, Guillermina Font, Jordi Manes, 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 (intra-day precision), reproducibility (inter-day precision), and matrix effects to check suitability...
October 25, 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
#2
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 7, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28982053/phosphate-stresses-affect-ionome-and-metabolome-in-tea-plants
#3
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
#4
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 18, 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
#5
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
#6
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
#7
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
#8
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
#9
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
https://www.readbyqxmd.com/read/28070878/effects-of-caffeic-acid-and-quercetin-on-in-vitro-permeability-metabolism-and-in-vivo-pharmacokinetics-of-melatonin-in-rats-potential-for-herb-drug-interaction
#10
Snehasis Jana, Himanshu Rastogi
BACKGROUND AND OBJECTIVES: Melatonin is a popular dietary supplement and also considered as pharmaceutical product for sleep disorders. Caffeic acid and quercetin are widely distributed in leafy vegetables, fruits, tea extract, and both are used as natural antioxidant. There is an immense concern for health researchers to study the herb/food-drug interactions of melatonin. It is mainly metabolized by CYP1A2 in human so that herbs/foods containing cytochrome P450 (CYP) inhibitors can affect pharmacokinetics of melatonin...
January 9, 2017: European Journal of Drug Metabolism and Pharmacokinetics
https://www.readbyqxmd.com/read/27957687/evaluation-of-an-enzyme-immunoassay-for-the-detection-of-the-mycotoxin-tenuazonic-acid-in-sorghum-grains-and-sorghum-based-infant-food
#11
Madeleine Gross, Stefan Asam, Michael Rychlik
An enzyme-linked immunosorbent assay (ELISA) for the Alternaria mycotoxin tenuazonic acid (TeA) was evaluated by comparative analysis of naturally contaminated sorghum grains and sorghum-based infant food, using a stable isotope dilution LC-MS assay (SIDA; limit of detection (LOD) 1.0 μg/kg) as the reference method. LODs of the ELISA were 30 μg/kg in sorghum grains and 220 μg/kg in sorghum-based infant cereals. With SIDA, 100% of the samples (n = 28) had been positive for TeA in a concentration range of 6-584 μg/kg (mean 113 μg/kg)...
February 2017: Mycotoxin Research
https://www.readbyqxmd.com/read/27725073/high-throughput-analytical-techniques-for-the-determination-of-the-residues-of-653-multiclass-pesticides-and-chemical-pollutants-in-tea-part-vii-a-gc-ms-gc-ms-ms-and-lc-ms-ms-study-of-the-degradation-profiles-of-pesticide-residues-in-green-tea
#12
Qiao-Ying Chang, Guo-Fang Pang, Chun-Lin Fan, Hui Chen, Fang Yang, Jie Li, Bi-Fang Wen
GC-MS, GC-tandem MS (MS/MS), and LC-MS/MS were used to mathematically define the degradation profiles of pesticide residues in two field trials. Nineteen pesticides were studied in the first field trial and 11 in the second. The results of the field trials demonstrated that the degradation profiles of pesticide residues in green tea can be described with power functions to successfully estimate the amount of time, following pesticide application, pesticide residues appearing in tea in concentrations at and/or above the maximum residue limit (MRL) decrease to concentrations below the MRL...
November 1, 2016: Journal of AOAC International
https://www.readbyqxmd.com/read/27619091/golf-ball-assisted-electrospray-ionization-of-mass-spectrometry-for%C3%A2-the%C3%A2-determination-of-trace-amino-acids-in-complex-samples
#13
Yen-Hsien Li, Chung-Yu Chen, Cheng-Hsiung Kuo, Maw-Rong Lee
During the electrospray ionization (ESI) process, ions move through a heated capillary aperture to be detected on arrival at a mass analyzer. However, the ESI process creates an ion plume, which expands into an ion cloud with an area larger than that of the heated capillary aperture, significantly contributing to an ion loss of 50% due to coulombic repulsion. The use of DC and RF fields to focus ions from the ion source into the vacuum chamber has been proposed in the literature, but the improvement of ion transmission efficiency is limited...
September 28, 2016: Analytica Chimica Acta
https://www.readbyqxmd.com/read/27507726/automated-multi-plug-filtration-cleanup-for-liquid-chromatographic-tandem-mass-spectrometric-pesticide-multi-residue-analysis-in-representative-crop-commodities
#14
Yuhong Qin, Jingru Zhang, Yuan Zhang, Fangbing Li, Yongtao Han, Nan Zou, Haowei Xu, Meiyuan Qian, Canping Pan
An automated multi-plug filtration cleanup (m-PFC) method on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) extracts was developed. The automatic device was aimed to reduce labor-consuming manual operation workload in the cleanup steps. It could control the volume and the speed of pulling and pushing cycles accurately. In this work, m-PFC was based on multi-walled carbon nanotubes (MWCNTs) mixed with other sorbents and anhydrous magnesium sulfate (MgSO4) in a packed tip for analysis of pesticide multi-residues in crop commodities followed by liquid chromatography with tandem mass spectrometric (LC-MS/MS) detection...
September 2, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/27211616/optimized-combination-of-dilution-and-refined-quechers-to-overcome-matrix-effects-of-six-types-of-tea-for-determination-eight-neonicotinoid-insecticides-by-ultra-performance-liquid-chromatography-electrospray-tandem-mass-spectrometry
#15
Weiting Jiao, Yu Xiao, Xiaosan Qian, Mengmeng Tong, Yizheng Hu, Ruyan Hou, Rimao Hua
Liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) is a primary tool for analysis of low volatility compounds in complex matrices. However, complex matrices, such as different types of tea, complicate analysis through ionization suppression or enhancement. In this study, sample preparation by a refined QuEChERS method combined with a dilution strategy removed almost all matrix effects caused by six types of tea. Tea samples were soaked with water and extracted with acetonitrile, cleaned up with a combination of PVPP (160mg) and GCB (20mg), and dried...
November 1, 2016: Food Chemistry
https://www.readbyqxmd.com/read/27137993/swapdt-a-method-for-short-time-withering-assessment-of-probability-for-drought-tolerance-in-camellia-sinensis-validated-by-targeted-metabolomics
#16
Christopher Nyarukowa, Robert Koech, Theodor Loots, Zeno Apostolides
Climate change is causing droughts affecting crop production on a global scale. Classical breeding and selection strategies for drought-tolerant cultivars will help prevent crop losses. Plant breeders, for all crops, need a simple and reliable method to identify drought-tolerant cultivars, but such a method is missing. Plant metabolism is often disrupted by abiotic stress conditions. To survive drought, plants reconfigure their metabolic pathways. Studies have documented the importance of metabolic regulation, i...
July 1, 2016: Journal of Plant Physiology
https://www.readbyqxmd.com/read/26782294/bioanalytical-lc-ms-study-of-potential-bacterial-transglycosylation-inhibitors
#17
Bart Blanchaert, Ismail Murat Palabiyik, Alper Gökbulut, Ming-Juan Wang, Zhong Dai, Feng Wei, Shuang-Cheng Ma, Erwin Adams, Ann Van Schepdael
Bacterial transglycosylation is an interesting target in antibiotic drug development. An in vitro transglycosylation assay was developed and used to search for possible inhibitors of Staphylococcus aureus Penicillin Binding Protein 2-mediated transglycosylation. Since the substrate, Lipid II, has no UV-chromophore, the assay relies on LC coupled to MS for analysis of the incubation mixtures. Extracts from Thymus sipyleus, Salvia verticillata, Salvia virgata and Oolong tea were tested, as well as epigallocatechin gallate and ursolic acid, which are chemical compounds derived from plants...
August 5, 2016: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/26608291/lc-ms-based-metabolomic-investigation-of-chemopreventive-phytochemical-elicited-metabolic-events
#18
Lei Wang, Dan Yao, Chi Chen
Phytochemicals are under intensive investigation for their potential use as chemopreventive agents in blocking or suppressing carcinogenesis. Metabolic interactions between phytochemical and biological system play an important role in determining the efficacy and toxicity of chemopreventive phytochemicals. However, complexities of phytochemical biotransformation and intermediary metabolism pose challenges for studying phytochemical-elicited metabolic events. Metabolomics has become a highly effective technical platform to detect subtle changes in a complex metabolic system...
2016: Methods in Molecular Biology
https://www.readbyqxmd.com/read/26607316/online-screening-of-nitric-oxide-scavengers-in-natural-products-using-high-performance-liquid-chromatography-coupled-with-tandem-diode-array-and-fluorescence-detection
#19
Dapeng Li, Ting Wang, Yujie Guo, Yuanjia Hu, Boyang Yu, Jin Qi
Nitric oxide (NO) is an important cellular signaling molecule with extensive physiological and pathophysiological effects. NO scavengers have the potential to treat inflammation, septic shock and other related diseases, and numerous examples have been chemically synthesized or isolated from natural products. The chemical diversity of natural products, however, means that a huge effort is necessary to efficiently screen and identify bioactive compounds, especially NO scavengers. In this article, we propose an effective analytical method to screen for NO scavengers in three natural products using an online system that couples high performance liquid chromatography with tandem diode array and fluorescence detection (HPLC-DAD-FLD)...
December 18, 2015: Journal of Chromatography. A
https://www.readbyqxmd.com/read/26578210/simultaneous-analysis-of-mono-di-and-tri-ethanolamine-in-cosmetic-products-using-liquid-chromatography-coupled-tandem-mass-spectrometry
#20
Kyong-Oh Shin, Yong-Moon Lee
Alkanolamines such as monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA) are used as wetting agents in shampoos, lotions, creams, and other cosmetics. DEA is widely used to provide lather in shampoos and maintain a favorable consistency in lotions and creams. Although DEA is not harmful, it may react with other ingredients in the cosmetic formula after extended storage periods to form an extremely potent carcinogen called nitrosodiethanolamine (NDEA), which is readily absorbed through the skin and has been linked to the development of stomach, esophagus, liver, and bladder cancers...
January 2016: Archives of Pharmacal Research
keyword
keyword
106524
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"