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https://www.readbyqxmd.com/read/28929549/uplc-qtof-ms-e-based-diagnostic-product-ion-filtering-to-unveil-unstable-c6-c2-glucoside-conjugates-in-forsythia-suspensa
#1
Yong-Gang Xia, Jun Liang, Xin-Dong Guo, Hui-Min Sun, Hai-Xue Kuang
Forsythia suspensa contains C6 -C2 glucoside conjugates (CCGCs) that are chemically unstable, thereby hindering their isolation and purification. In the present study, ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF) was utilized to screen and identify unstable CCGCs in the fruits and leaves of F. suspensa without any tedious isolation and purified process based on independent information acquisition (also called MS(E) ) and individual MS/MS experiments. Diagnostic product ion filtering (DPIF) was further applied to mine unknown analogs in MS(E) high energy levels based on characteristic m/z of key substructures...
September 20, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28925005/simultaneous-qualitative-and-quantitative-analyses-of-triterpenoids-in-ilex-pubescens-by-ultra-high-performance-liquid-chromatography-coupled-with-quadrupole-time-of-flight-mass-spectrometry
#2
Di Cao, Qing Wang, Jing Jin, Maosong Qiu, Lian Zhou, Xinghong Zhou, Hui Li, Zhongxiang Zhao
INTRODUCTION: Ilex pubescens Hook et Arn mainly contains triterpenoids that possess antithrombotic, anti-inflammatory and analgesic effects. Quantitative and qualitative analyses of the triterpenoids in I. pubescens can be useful for determining the authenticity and quality of raw materials and guiding its clinical preparation. OBJECTIVES: To establish a method for rapid and comprehensive analysis of triterpenoids in I. pubescens using ultra-high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS), which will also be applied to evaluate the contents of nine triterpenoids among root, root heartwood and root bark of I...
September 18, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28922607/antdas-automatic-data-analysis-strategy-for-uplc-qtof-based-nontargeted-metabolic-profiling-analysis
#3
Hai-Yan Fu, Xiao-Ming Guo, Yue-Ming Zhang, Jing-Jing Song, Qing-Xia Zheng, Ping-Ping Liu, Peng Lu, Qian-Si Chen, Yong-Jie Yu, Yuanbin She
High-quality data analysis methodology remains a bottleneck for metabolic profiling analysis based on ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The present work aims to address this problem by proposing a novel data analysis strategy wherein (1) chromatographic peaks in the UPLC-QTOF dataset are automatically extracted by using an advanced multiscale Gaussian smoothing-based peak extraction strategy. (2) A peak annotation stage is used to cluster fragment ions that belong to the same compound...
September 18, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28921579/material-basis-studies-of-anti-influenza-a-active-ingredients-in-tanreqing-injection
#4
Haiyan Zhu, Mingchang Chen, Xunlong Shi, Chenchen Shi, Chenggang Huang
Tanreqing Injection (TRQ) has been used primarily in treating infections of the upper respiratory tract and serious influenza in China, as a classical compound herbal recipe. TRQ had been demonstrated its effects of clearing heat, eliminating phlegm, detoxification, reducing inflammation and alleviating cough. The survival rate, histopathology of lungs and viral titers in mice were evaluated in this study to verify the curative effect of TRQ. However, there is not enough information about the components. In the present study, a high-performance and practical LC/QTOF/MS method was developed for characterization and identification of the natural ingredients in TRQ...
September 15, 2017: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/28920615/the-phenolic-profiles-of-radix-tetrastigma-after-solid-phase-extraction-spe-and-their-antitumor-effects-and-antioxidant-activities-in-h22-tumor-bearing-mice
#5
Yong Sun, Rong Tsao, Fang Chen, Hongyan Li, Han Peng, Li Jiang, Yuhuan Chen, Zeyuan Deng
Radix Tetrastigma (RT), a herbal medicine and functional food in China, showed strong antiproliferative activities in vitro. However, the effects and the underlying mechanism of phenolic-rich extract of RT in H22 tumor-bearing mice are still unknown. Thus, the phenolic profiles and antitumor/antioxidant activities of a solid phase extraction (SPE) semi-purified extract of RT were investigated by a combination of chemical assays, LC-QTOF-MS/LC-QqQ-MS techniques and a tumor-bearing mice model. As a result, the total phenolic/flavonoid contents (TPC/TFC) and 24 individual phenolics were identified and quantified, which showed higher contents than that of crude extract...
September 18, 2017: Food & Function
https://www.readbyqxmd.com/read/28915418/purification-identification-and-molecular-mechanism-of-two-dipeptidyl-peptidase-iv-dpp-iv-inhibitory-peptides-from-antarctic-krill-euphausia-superba-protein-hydrolysate
#6
Wei Ji, Chaohua Zhang, Hongwu Ji
Dipeptidyl peptidase IV (DPP-IV) played an important role in blood glucose regulation. Inhibition of DPP-IV may improve glycemic control in diabetics by preventing the rapid breakdown of incretin hormones and prolonging their physiological action. In this study, Antarctic krill (Euphausia superba) protein was hydrolyzed using animal proteolytic enzymes. The hydrolysate was purified sequentially by ultrafiltration, gel filtration chromatography and reversed phase high-performance liquid chromatography (RP-HPLC)...
September 5, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28913969/spray-inlet-microwave-plasma-torch-ionization-tandem-mass-spectrometry-for-the-direct-detection-of-drug-samples-in-liquid-solutions
#7
Meng Miao, Gaosheng Zhao, Yaliang Wang, Li Xu, Junguo Dong, Ping Cheng
RATIONALE: Drug abuse or dependence results in a series of social problems, including crime and traffic accidents. Spray inlet microwave plasma torch tandem mass spectrometry (MPT-MS/MS) was developed and used for the direct detection of such drugs in liquid solutions. METHODS: Drug sample solutions were directly sprayed into the flame of MPT by a sampling pump and the ions produced by Penning ionization and ion-molecule reactions were guided into a QTOF tandem mass spectrometer for mass analysis...
September 14, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28912717/global-metabolomics-reveals-the-metabolic-dysfunction-in-ox-ldl-induced-macrophage-derived-foam-cells
#8
Wenjuan Xu, Ziyi Wei, Jiaojiao Dong, Feipeng Duan, Kuikui Chen, Chang Chen, Jie Liu, Xiaowei Yang, Lianming Chen, Hongbin Xiao, An Liu
Atherosclerosis (AS) is a chronic disorder of large arteries that is a major risk factors of high morbidity and mortality. Oxidative modification LDL is one of the important contributors to atherogenesis. Macrophages take up ox-LDL and convert into foam cells, which is the hallmark of AS. To advance the understanding of the metabolic perturbation involved in ox-LDL induced macrophage-derived foam cells and discover the potential biomarkers of early AS, a global metabolomics approach was applied based on UHPLC-QTOF/MS...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/28911226/identification-of-the-ubiquitous-antioxidant-tripeptide-glutathione-as-a-fruit-fly-semiochemical
#9
Xavier Cheseto, Donald L Kachigamba, Sunday Ekesi, Mary Ndung'u, Peter E A Teal Deceased, John J Beck, Baldwyn Torto
Many insects mark their oviposition sites with a host marking pheromone (HMP) to deter other females from over-exploiting these sites. Previous studies have identified and used HMPs to manage certain fruit fly species; however, few are known for African indigenous fruit flies. The HMP of the African fruit fly, Ceratitis cosyra, was identified as the ubiquitous plant and animal antioxidant tripeptide, glutathione (GSH). GSH was isolated from the aqueous extract of adult female fecal matter, and characterized by LC-QTOF-MS...
September 15, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28900196/characterization-of-a-new-pathway-that-activates-lumisterol-in-vivo-to-biologically-active-hydroxylumisterols
#10
Andrzej T Slominski, Tae-Kang Kim, Judith V Hobrath, Zorica Janjetovic, Allen S W Oak, Arnold Postlethwaite, Zongtao Lin, Wei Li, Yukimasa Takeda, Anton M Jetten, Robert C Tuckey
Using LC/qTOF-MS we detected lumisterol, 20-hydroxylumisterol, 22-hydroxylumisterol, 24-hydroxylumisterol, 20,22-dihydroxylumisterol, pregnalumisterol, 17-hydroxypregnalumisterol and 17,20-dihydroxypregnalumisterol in human serum and epidermis, and the porcine adrenal gland. The hydroxylumisterols inhibited proliferation of human skin cells in a cell type-dependent fashion with predominant effects on epidermal keratinocytes. They also inhibited melanoma proliferation in both monolayer and soft agar. 20-Hydroxylumisterol stimulated the expression of several genes, including those associated with keratinocyte differentiation and antioxidative responses, while inhibiting the expression of others including RORA and RORC...
September 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28900168/identification-of-key-metabolic-changes-during-liver-fibrosis-progression-in-rats-using-a-urine-and-serum-metabolomics-approach
#11
Hong Chang, Hong-Yu Meng, Shu-Min Liu, Yu Wang, Xiao-Xu Yang, Fang Lu, Hong-Yu Wang
Reversibility of hepatic fibrosis is an intrinsic response to chronic injury, and with on-going damage, fibrosis can progress to its end-stage consequence, cirrhosis. Non-invasive and reliable biomarkers for early detection of liver fibrosis are needed. Based on the CCl4-induced liver fibrosis rat model, urinary and serum metabolic profiling performed by LC-QTOF-MS associated with histological progression were utilized to identify liver fibrosis-specific potential biomarkers for early prediction and to reveal significant fibrotic pathways and their dynamic changes in different stages of liver fibrosis...
September 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28895401/serum-metabolic-fingerprinting-identified-putatively-annotated-sphinganine-isomer-as-a-biomarker-of-wolfram-syndrome
#12
Agnieszka Zmyslowska, Michal Ciborowski, Maciej Borowiec, Wojciech Fendler, Karolina Pietrowska, Ewa Parfieniuk, Karolina Antosik, Aleksandra Pyziak, Arleta Waszczykowska, Adam Kretowski, Wojciech Mlynarski
Wolfram syndrome (WFS) is an example of a rare neurodegenerative disease with coexisting endocrine symptoms including diabetes mellitus as the first clinical symptom. Treatment of WFS is still only symptomatic and associated with poor prognosis. Potential markers of disease progression which could be useful for possible intervention trials are not available. Metabolomics has potential to identify such markers. In the present study serum fingerprinting by LC-QTOF-MS was performed in patients with WFS (n=13) and in patients with T1D (n=27)...
September 12, 2017: Journal of Proteome Research
https://www.readbyqxmd.com/read/28895363/-characterization-of-n-glycosylation-in-an-anti-egfr-monoclonal-antibody-produced-by-different-expression-systems
#13
Chong Wang, Huaizu Guo
The use of mammalian expression systems results in a remarkable heterogeneity of mAb products, generally due to post-translational modifications, and glycosylation is a critical post-translation modification because it has a profound impact on the safety and efficacy of mAbs. The present study was designed to explore the impact of a different expression system on mAb N-glycosylation. The detailed structures of individual glycans between anti-EGFR monoclonal antibodies produced by different expression systems were successfully characterized at the level of free oligosaccharides using liquid chromatography electrospray ionization quadrupole time-of-fight mass spectrometry (LC-ESI-QTof MS)...
June 25, 2017: Sheng Wu Gong Cheng Xue Bao, Chinese Journal of Biotechnology
https://www.readbyqxmd.com/read/28895237/a-comprehensive-characterisation-of-rosemary-tea-obtained-from-rosmarinus-officinalis-l-collected-in-a-sub-humid-area-of-tunisia
#14
Mariem Achour, Raquel Mateos, Maha Ben Fredj, Ali Mtiraoui, Laura Bravo, Saad Saguem
INTRODUCTION: Rosemary (Rosmarinus officinalis L.) is an aromatic plant common in Tunisia and it is widely consumed as a tea in traditional cuisine and in folk medicine to treat various illnesses. Currently, most research efforts have been focused on rosemary essential oil, alcoholic and aqueous extracts, however, little is reported on rosemary infusion composition. OBJECTIVE: To investigate compounds present in rosemary tea obtained from Rosmarinus officinalis L...
September 12, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28895216/metabolic-alterations-in-two-cirsium-species-identified-at-distinct-phenological-stages-using-uplc-qtof-ms
#15
Min-Sun Kim, Miso Nam, Geum-Sook Hwang
INTRODUCTION: Cirsium chanroenicum and C. setidens are commonly used both in traditional folk medicine and as a food source. The quality of different species of Cirsium at different harvest times is a function of their metabolite composition, which is determined by the phenological stage. OBJECTIVE: We sought to determine the differences in the metabolite composition of two species of Cirsium during different phenological stages using ultra-performance liquid chromatography (UPLC) quadrupole time-of-flight (QTOF) mass spectrometry (MS)...
September 12, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28895207/structural-characterisation-of-alkaloids-in-leaves-and-roots-of-stephania-kwangsiensis-by-lc-qtof-ms
#16
Yan Shangguan, Jiayong He, Yun Kang, Yaqin Wang, Ping Yang, Jixian Guo, Jianming Huang
INTRODUCTION: The tuberous roots of Stephania kwangsiensis, which contain bioactive alkaloids, are used as a traditional Chinese medicine. Overexploitation of the roots has made the plant increasingly rare, and the abundant leaves of the same plant may offer a potential alternative. However, there is insufficient phytochemical information for a comparison of alkaloid compositions in the two parts. OBJECTIVE: To characterise and compare the alkaloids in the leaves and roots of S...
September 12, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28889959/metabolic-profiles-revealed-anti-ischemia-reperfusion-injury-of-yangxinshi-tablet-in-rats
#17
Hai Zhang, Yahong Zhao, Zhengxiang Xia, Hongli Du, Yue Gao, Dan Xue, Zhenyu Zhu, Yifeng Chai
ETHNOPHARMACOLOGICAL RELEVANCE: Myocardial ischemia-reperfusion (I/R) injury is a serious injury that is resulted from the recovery of blood supply after myocardial ischemia. Yangxinshi tablet is a compound Chinese herbal preparation and often used to alleviate the myocardial ischemia in clinical, but its protective mechanism of anti-myocardial ischemia reperfusion injury remains unclear. The objective of this study was to evaluate the anti-I/R injury effect of Yangxinshi tablet on a myocardial I/R rat model and to identify serum biomarker metabolites associated with I/R based on ultra-high performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF/MS) metabolomic method, and explore the metabolic mechanism of anti-I/R injury of Yangxinshi tablet...
September 7, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/28889763/identification-of-methylated-metabolites-of-oat-avenanthramides-in-human-plasma-using-uhplc-qtof-ms
#18
Jason Walsh, Jordan Haddock, Jeffrey B Blumberg, Diane L McKay, Xiaoyong Wei, Gregory Dolnikowski, C-Y Oliver Chen
Oat avenanthramides (AVAs) are a group of phenolic alkaloids, consisting of an anthranilic acid and a hydroxycinnamic acid linked by a pseudo-peptide bond. Bioavailability of AVA is poor in humans, suggesting transformations for rapid excretion. Thus, we aim to identify metabolites of AVA isomers in plasma of humans after consuming AVA-enriched oats. After lipid removal, AVA and their metabolites in plasma were extracted with ethyl acetate and analysed using an Agilent UHPLC-QToF-MS. Pharmacokinetics of AVA-O showed a bimodal distribution with Cmax1 and 2 for AVA-O at 5...
September 11, 2017: International Journal of Food Sciences and Nutrition
https://www.readbyqxmd.com/read/28888460/impact-of-boiling-on-free-and-bound-phenolic-profile-and-antioxidant-activity-of-commercial-gluten-free-pasta
#19
Gabriele Rocchetti, Luigi Lucini, Giulia Chiodelli, Gianluca Giuberti, Domenico Montesano, Francesco Masoero, Marco Trevisan
Cooking by boiling dry pasta could have varying degrees of influence on nutritional and functional components. In the present study, its effect on total phenolic content and antioxidant capacity, as well as on the comprehensive profile of free and bound phenolics, was investigated in six commercial gluten-free (GF) pasta products. Overall, the heat treatment caused a significant reduction (P<0.01) of the total phenolic content as well as FRAP reducing power and ORAC radical scavenging, with significant differences among the pasta samples considered...
October 2017: Food Research International
https://www.readbyqxmd.com/read/28888436/the-influence-of-ripening-stage-and-region-on-the-chemical-compounds-in-mulberry-fruits-morus-atropurpurea-roxb-based-on-uplc-qtof-ms
#20
Jiufang Yang, Haichao Wen, Lei Zhang, Xiaoxu Zhang, Zheng Fu, Jingming Li
Mulberries (Morus atropurpurea Roxb.) are rich in beneficial nutrients and secondary metabolites. Dramatic climate differences between western and eastern China lead to differences among the fruiting habits of mulberries grown in these regions. In this study, Xinjiang and Jiangsu, two regions in western and eastern China, respectively, were selected as sites where mulberry fruits (MFs) at different ripening stages were sampled. Their individual components, including both targeted and non-targeted chemical compounds, were detected by rapid ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS)...
October 2017: Food Research International
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