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https://www.readbyqxmd.com/read/29775200/cadmium-induced-changes-in-the-production-of-siderophores-by-a-plant-growth-promoting-strain-of-pseudomonas-fulva
#1
Dominika Thiem, Michał Złoch, Renata Gadzała-Kopciuch, Sonia Szymańska, Christel Baum, Katarzyna Hrynkiewicz
The impact of increasing Cd2+ exposure on the quality and quantity of siderophores produced by a plant growth promoting Pseudomonas fulva strain was tested to gain insight into the degree of change. P. fulva was cultured in the increasing concentrations of Cd2+ (0, 0.5, 1.0, 2.0 mM). The secreted siderophores were separated by HPLC and characterized by UHPLC-QTOF/MS. In the presence of 2 mM Cd2+ synthesis of siderophores (hydroxamates, catecholates, phenolates) was mitigated compared to the treatments with lower concentrations of Cd2+ (0...
May 18, 2018: Journal of Basic Microbiology
https://www.readbyqxmd.com/read/29770982/characterisation-of-phenolic-compounds-by-uplc-qtof-ms-ms-of-geopropolis-from-the-stingless-bee-melipona-subnitida-janda%C3%A3-ra
#2
Silvana Alves de Souza, Telma Maria Guedes da Silva, Eva Monica Sarmento da Silva, Celso Amorim Camara, Tania Maria Sarmento Silva
INTRODUCTION: Melipona subnitida Ducke (jandaíra) is a stingless bee native to north-eastern Brazil, which produces geopropolis, a mixture of beeswax, plant resins, pollens and earth that is used for sealing beehives. OBJECTIVE: To extend the knowledge on phenolic compounds in fractions obtained by C18-solid phase extraction (SPE) of nine geopropolis samples from Melipona subnitida collected at different times. METHODOLOGY: Chromatographic profiles of nine samples of geopropolis from jandaíra were analysed by ultra-performance liquid chromatography coupled with a diode array detector and quadrupole time-of-flight mass spectrometry (UPLC-DAD-QTOF-MS/MS) and combined with the use of data-independent acquisition (MSE) for the profiling and structural characterisation of the phenolic compounds...
May 17, 2018: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/29766315/validation-and-determination-of-nine-pfcs-in-surface-water-and-sediment-samples-using-uplc-qtof-ms
#3
B O Fagbayigbo, B O Opeolu, O S Fatoki, O S Olatunji
In this study, an analytical method for the routine determination of nine perfluorinated compounds (PFCs), using ultra performance liquid chromatography coupled to a quadrupole time-of-flight mass spectrometer (UPLC-QTOF-MS), was developed, validated, and used for their assay in surface water and sediments. The method yielded good linearity with a correlation coefficient (R2 ) ranging between 0.991 and 0.999 for all the compounds investigated. Limits of detection (LOD) ranged between 0.02 and 0.08 ng/l, while the limit of quantification (LOQ) ranged from 0...
May 15, 2018: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/29761437/plant-lipidomics-using-uplc-qtof-ms
#4
Yozo Okazaki, Kazuki Saito
Lipids are primary metabolites used for energy storage, signal transduction, and pigmentation, besides being common membrane components. Considering the importance of comprehensive lipid analysis (lipidomics) for a detailed understanding of cellular metabolic states, this chapter introduces liquid chromatography-quadrupole time-of-flight mass spectrometry as a powerful untargeted plant lipidomics technique.
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/29756280/determination-of-phenolic-compounds-and-antioxidant-activities-from-peel-flesh-seed-of-guava-psidium-guajava-l
#5
Xuan Liu, Xu Yan, Jinfeng Bi, Jianing Liu, Mo Zhou, Xinye Wu, Qinqin Chen
White-flesh guava is widely planted in tropical or subtropical areas of Southeast Asia. Despite of folk statements on specific function, few researches are focused on the description of its plant secondary metabolites. In the present work, contents of total phenolics and flavonoids as well as antioxidant activity from different parts (peel, flesh and seed) were determined. The constituents of ethanol extracts were characterized by HPLC-QTOF-MS. A total of 69 phenolic compounds as well as 9 polar compounds were detected, with flavonoids, hydrolyzable tannins, phenolic acid derivatives and benzophenones of the four predominant phenolic compounds...
May 13, 2018: Electrophoresis
https://www.readbyqxmd.com/read/29753271/biobegradation-and-metabolic-mechanism-of-cyprodinil-by-strain-acinetobacter-sp-from-a-contaminated-agricultural-soil-in-china
#6
Xiaoxin Chen, Sheng He, Xiaolu Liu, Jiye Hu
Using sequential soil and liquid culture enrichments with cyprodinil as the sole carbon source, a Gram-negative cyprodinil-degrader from cyprodinil-polluted agricultural soil was isolated. The sequencing analysis of 16 S rRNA indicated that the strain showed 99% homology to Acinetobacter sp. The strain could effectively degrade cyprodinil at the neutral condition. At the initial concentrations of 10, 20, 50, 100, 150 and 200 mg L-1 in minimal medium, cyprodinil was degraded by 10, 20, 49.3, 64.2, 57 and 24 mg L-1 within 14 days, respectively...
May 9, 2018: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/29753191/biodegradation-of-pyraclostrobin-by-two-microbial-communities-from-hawaiian-soils-and-metabolic-mechanism
#7
Xiaoxin Chen, Sheng He, Zhibin Liang, Qing X Li, Hai Yan, Jiye Hu, Xiaolu Liu
Pyraclostrobin has been widely and long-termly applicated to agricultural fields. The removal of pyraclostrobin from ecological environment has received wide attention. In this study, using sequential enrichments with pyraclostrobin as a sole carbon source, two microbial communities (HI2 and HI6) capable of catabolizing pyraclostrobin were obtained from Hawaiian soils. The microfloras analysis indicated that only Proteobacteria and Bacteroides could survive in HI2-soil after acclimatization, whereas the number of Proteobacteria in HI6-soil accounted for more than 99%...
April 27, 2018: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/29751487/preparation-and-antioxidant-activity-of-ethyl-linked-anthocyanin-flavanol-pigments-from-model-wine-solutions
#8
Lingxi Li, Minna Zhang, Shuting Zhang, Yan Cui, Baoshan Sun
Anthocyanin-flavanol pigments, formed during red wine fermentation and storage by condensation reactions between anthocyanins and flavanols (monomers, oligomers, and polymers), are one of the major groups of polyphenols in aged red wine. However, knowledge of their biological activities is lacking. This is probably due to the structural diversity and complexity of these molecules, which makes the large-scale separation and isolation of the individual compounds very difficult, thus restricting their further study...
May 3, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29751075/analysis-by-uplc-ms-qtof-and-antifungal-activity-of-guava-psidium-guajava-l
#9
Camila Fonseca Bezerra, Janaína Esmeraldo Rocha, Maria Karollyna do Nascimento Silva, Thiago Sampaio de Freitas, Amanda Karine de Sousa, Antônia Thassya Lucas Dos Santos, Rafael Pereira da Cruz, Maciel Horácio Ferreira, Josefa Carolaine Pereira da Silva, Antonio Judson Targino Machado, Joara Nályda Pereira Carneiro, Débora Lima Sales, Henrique Douglas Melo Coutinho, Paulo Riceli Vasconcelos Ribeiro, Edy Sousa de Brito, Maria Flaviana Bezerra Morais-Braga
Psidium guajava L. is a plant widely used for food and in folk medicine all over the world. Studies have shown that guava leaves have antifungal properties. In this study, Flavonoid and Tannic fractions were tested to investigate their chemical composition and antifungal potential in vitro.21 compounds in the two fractions, presenting a higher content of phenolic compounds. The antifungal assays were performed against Candida albicans, Candida tropicalis and Candida krusei by microdilution to determine the IC50 and the cell viability curve...
May 8, 2018: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/29745330/metabolism-of-synthetic-cannabinoids-encountered-in-clinical-casework-major-in-vivo-metabolites-of-jwh-007-jwh-019-jwh-203-jwh-307-ur-144-xlr-11-am-2201-mam-2201-and-am-694-in-human-urine-using-lc-ms-ms
#10
Volker Auwarter, Melanie Hutter, S Broecker, Stefan Kneisel, Floria Franz, Simon D Brandt
BACKGROUND: `Herbal mixtures` containing synthetic cannabinoid receptor agonists (SCRAs) are promoted as legal alternative to marihuana and are easily available via the Internet. Keeping analytical methods for the detection of these SCRAs up-to-date is a continuous challenge for clinicians and toxicologists due to the high diversity of the chemical structures and the frequent emergence of new compounds. Since many SCRAs are extensively metabolized, analytical methods used for urine testing require previous identification of the major metabolites of each compound...
May 9, 2018: Current Pharmaceutical Biotechnology
https://www.readbyqxmd.com/read/29738966/sulfotransferase-catalyzed-biotransformation-of-liguzinediol-and-comparison-of-its-metabolism-in-different-species-using-uflc-qtof-ms
#11
Fei Shen, Hong-Mei Wen, Chen-Xiao Shan, An Kang, Bang Dong, Chuan Chai, Ji-Yun Zhang, Qi Zhang, Wei Li
Liguzinediol (2,5-dihydroxymethyl-3,6-dimethylpyrazine, LZDO) is a potential agent for the low-risk treatment of heart failure. 2-N-acetylcysteine-LZDO (2-NAC-LZDO) and 2-cysteine-LZDO (2-Cys-LZDO) are major LZDO metabolites found in the pharmacokinetic studies of rats and beagle dogs. To elucidate the biotransformation pathway and related enzymes, an incubation system with 3'-phosphoadenosine-5'-phosphosulfate (PAPS) as a cofactor and N-acetylcysteine (NAC) as a trapping agent was established using liver cytosol...
May 1, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29737914/lipidomics-reveal-aryl-hydrocarbon-receptor-ahr-regulated-lipid-metabolic-pathway-in-alpha-naphthyl-isothiocyanate-anit-induced-intrahepatic-cholestasis
#12
Bao-Long Wang, Chang-Wen Zhang, Liang Wang, Kun-Long Tang, Naoki Tanaka, Frank J Gonzalez, Yong Xu, Zhong-Ze Fang
1. Ultra-performance liquid chromatography coupled with electrospray ionization quadrupole mass spectrometry (UPLC-ESI-QTOF MS)-based lipidomics was employ to elucidate new mechanism of alpha-naphthyl isothiocyanate (ANIT)-induced intrahepatic cholestasis in mice. 2. Multiple lipid components significantly increased in ANIT-induced intrahepatic cholestasis, including PC 16:0, 20:4, PC 16:0, 22:6, PC 16:0, 18:2, LPC 18:2, PC 18:2, LPC 18:1, PC 18:1, 14:0, SM 18:1, 16:0, oleoylcarnitine, and palmitoylcarnitine...
May 8, 2018: Xenobiotica; the Fate of Foreign Compounds in Biological Systems
https://www.readbyqxmd.com/read/29737517/phytochemical-composition-of-smoothies-combining-pomegranate-juice-punica-granatum-l-and-mediterranean-minor-crops-pur%C3%A3-es-ficus-carica-cydonia-oblonga-and-ziziphus-jujube
#13
M Cano-Lamadrid, P Nowicka, F Hernández, A A Carbonell-Barrachina, A Wojdyło
BACKGROUND: As World Health Organization suggested daily intake of fruits and vegetables is lower than the recommended dietary intake (RDI). A good option to increase the intake of fruit and vegetables is the smoothies consumption. This work evaluated the effect of adding fig, jujube, or quince purée to pomegranate juice (cultivars Wonderful and Mollar de Elche) in preparing smoothies at two ratios purée:juice (40:60 and 60:40) on the composition of minerals, sugars, organic acids, vitamin C, antioxidant activity, and polyphenols...
May 8, 2018: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/29735094/tea-and-coffee-time-with-bacteria-investigation-of-uptake-of-key-coffee-and-tea-phenolics-by-wild-type-e-coli
#14
Inamullah Hakeem Said, Selin Gencer, Matthias S Ullrich, Nikolai Kuhnert
Dietary phenolic compounds are often transformed by gut microbiota prior to absorption. This transformation may modulate their biological activities. Many fundamental questions still need to be addressed to understand how the gut microbiota-diet interactions affect human health. Herein, a UHPLC-QTOF mass spectrometry-based method for the quantification of uptake and determination of intracellular bacterial concentrations of dietary phenolics from coffee and tea was developed. Quantitative uptake data for selected single purified phenolics were determined...
June 2018: Food Research International
https://www.readbyqxmd.com/read/29735052/rapid-discrimination-of-raw-and-sulfur-fumigated-smilax-glabra-based-on-chemical-profiles-by-uhplc-qtof-ms-ms-coupled-with-multivariate-statistical-analysis
#15
Lili He, Zhifeng Zhang, Yuan Liu, Dingqiao Chen, Muhua Yuan, Gengting Dong, Pei Luo, Zhigang Yan
Smilax glabra (SG) is commonly used as a traditional edible herb in eastern Asia. Recently, sulfur-fumigation has been frequently used in order to obtain better color and a longer storage lifetime. However, the chemical alterations caused by this process remain unknown. The aim of this research was to explore potential chemical differences between non-fumigated and sulfur-fumigated SG samples. A novel approach was developed by using ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) with principal component analysis (PCA) and orthogonal partial squared discriminant analysis (OPLS-DA)...
June 2018: Food Research International
https://www.readbyqxmd.com/read/29733313/an-hs-mrm-assay-for-the-quantification-of-host-cell-proteins-in-protein-biopharmaceuticals-by-liquid-chromatography-ion-mobility-qtof-mass-spectrometry
#16
Catalin Doneanu, Jing Fang, Yun Alelyunas, Ying Qing Yu, Mark Wrona, Weibin Chen
The analysis of low-level (1-100 ppm) protein impurities (e.g., host-cell proteins (HCPs)) in protein biotherapeutics is a challenging assay requiring high sensitivity and a wide dynamic range. Mass spectrometry-based quantification assays for proteins typically involve protein digestion followed by the selective reaction monitoring/multiple reaction monitoring (SRM/MRM) quantification of peptides using a low-resolution (Rs ~1,000) tandem quadrupole mass spectrometer. One of the limitations of this approach is the interference phenomenon observed when the peptide of interest has the "same" precursor and fragment mass (in terms of m/z values) as other co-eluting peptides present in the sample (within a 1-Da window)...
April 17, 2018: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/29730338/rapid-characterization-of-tcm-qianjinteng-by-uplc-qtof-ms-and-its-application-in-the-evaluation-of-three-species-of-stephania
#17
Jiao Xiao, Nannan Song, Tong Lu, Yingni Pan, Junyu Song, Gang Chen, Lu Sun, Ning Li
A method for rapid identification of bioactive components in herbals from Stephania species was developed by utilizing UPLC-QTOF-MS/MS in this study. Sixty-three alkaloids including the types of proaporphine, aporphine, protoberberine, morphine, hasubanan, benzylisoquinoline and bisbenzylisoquinoline were characterized. Among them, 29 components were selected for semi-quantitative analyses to characterize the difference of chemical compositions among three Stephania species. The results revealed that bisbenzylisoquinoline-type of alkaloids are the representative components of SB (Subgen...
April 26, 2018: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29729869/plasma-trimethylamine-n-oxide-is-associated-with-vulnerable-plaque-characteristics-in-cad-patients-as-assessed-by-optical-coherence-tomography
#18
Xinxin Liu, Zulong Xie, Meng Sun, Xuedong Wang, Ji Li, Jinjin Cui, Fengyun Zhang, Li Yin, Dan Huang, Jingbo Hou, Jinwei Tian, Bo Yu
BACKGROUND: Plaque vulnerability indicates the risk of a cardiovascular event. In the present study, we sought to analyze the relationship between trimethylamine N-oxide (TMAO), a gut microbiota metabolite from dietary phosphatidylcholine, and vulnerable plaque characteristics in patients with coronary artery disease (CAD). METHODS: One hundred eighty non-culprit plaques from 90 patients with ACS or with stable angina were assessed by optical coherence tomography (OCT)...
April 28, 2018: International Journal of Cardiology
https://www.readbyqxmd.com/read/29729740/quantification-of-steroid-hormones-in-plasma-using-a-surrogate-calibrant-approach-and-uhplc-esi-qtof-ms-ms-with-swath-acquisition-combined-with-untargeted-profiling
#19
Bernhard Drotleff, Manfred Hallschmid, Michael Lämmerhofer
In spite of demonstrated lack of accuracy and consistency, quantification of steroid hormones is still most commonly executed via immunoassays. Mass spectrometric methods with triple quadrupole instruments are well established and, because of their proven robustness and sensitivity, best suited for targeted analysis. However, recent studies have shown that high-resolution mass spectrometers, like quadrupole time-of-flight instruments (QTOF), show comparable performance in terms of quantification and can generate additional sample information via untargeted profiling workflows...
August 31, 2018: Analytica Chimica Acta
https://www.readbyqxmd.com/read/29727953/profiling-the-decomposition-products-of-perfluorooctane-sulfonate-pfos-irradiated-using-an-electron-beam
#20
Tae-Hun Kim, Seungho Yu, Yeowool Choi, Tae-Yong Jeong, Sang Don Kim
Perfluorooctane sulfonate (PFOS) has been found in wastewater treatment plants (WWTPs) and in surface water as a result of domestic uses of textiles, electronics, and surfactants. The detection of PFOS in the aqueous environment has been linked to hazardous biological effects including estrogenicity and genotoxicity. To provide an alternative to conventional processes, one of the radical-based advanced oxidation and reduction processes being tested for treatment of refractory compounds in water, involves the use of an electron beam...
August 1, 2018: Science of the Total Environment
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