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https://www.readbyqxmd.com/read/28743100/studies-on-secondary-metabolite-profiling-anti-inflammatory-potential-in-vitro-photoprotective-and-skin-aging-related-enzyme-inhibitory-activities-of-malaxis-acuminata-a-threatened-orchid-of-nutraceutical-importance
#1
Biswajit Bose, Hiranjit Choudhury, Pramod Tandon, Suman Kumaria
Malaxis acuminata D. Don., a small, terrestrial orchid, is endemic to tropical Himalayas at an altitude of 1200-2000m asl. The dried pseudobulbs are important ingredients of century old ayurvedic drug 'Ashtavarga' and a polyherbal immune-booster nutraceutical 'Chyavanprash', known to restore vigour, vitality and youthfulness. Considering tremendous medicinal importance of this threatened orchid species, a detailed study was undertaken for the first time to address its antioxidant potential, secondary metabolite contents and biological activities against skin-aging related enzymes (anti-collagenase, anti-elastase, anti-tyrosinase and xanthine oxidase) and anti-inflammatory activity (5-lipoxygenase and hyaluronidase) in different plant parts of wild and in vitro-derived plants of M...
July 12, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28743008/wastewater-contamination-in-antarctic-melt-water-streams-evidenced-by-virological-and-organic-molecular-markers
#2
L F L Tort, K Iglesias, C Bueno, A Lizasoain, M Salvo, J Cristina, N Kandratavicius, L Pérez, R Figueira, M C Bícego, S Taniguchi, N Venturini, E Brugnoli, R Colina, M Victoria
Human activities in the Antarctica including tourism and scientific research have been raised substantially in the last century with the concomitant impact on the Antarctic ecosystems through the release of wastewater mainly from different scientific stations activities. The aim of this study was to assess the wastewater contamination of surface waters and sediments of three melt-water streams (11 sites) by leaking septic tanks located in the vicinity of the Uruguayan Scientific Station in the Fildes Peninsula, King George Island, Antarctica, during summer 2015...
July 22, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28742883/effects-of-oral-florfenicol-and-azithromycin-on-gut-microbiota-and-adipogenesis-in-mice
#3
Rui Li, Hexing Wang, Qingfeng Shi, Na Wang, Zhijie Zhang, Chenglong Xiong, Jianxiang Liu, Yue Chen, Lufang Jiang, Qingwu Jiang
Certain antibiotics detected in urine are associated with childhood obesity. In the current experimental study, we investigated two representative antibiotics detected in urine, florfenicol and azithromycin, for their early effects on adipogenesis, gut microbiota, short-chain fatty acids (SCFAs), and bile acids in mice. Thirty C57BL/6 mice aged four weeks were randomly divided into three groups (florfenicol, azithromycin and control). The two experimental groups were administered florfenicol or azithromycin at 5 mg/kg/day for four weeks...
2017: PloS One
https://www.readbyqxmd.com/read/28742064/the-effect-of-biosilver-nanoparticles-on-different-bacterial-strains-metabolism-reflected-in-their-vocs-profiles
#4
Boguslaw Buszewski, Ileana Andreea Ratiu, Maciej Milanowski, Pawel Pomastowski, Tomasz Ligor
Silver nanoparticles use has spawned during the last years a growing interest for many researchers, due to their bacteriostatic and bactericidal properties and synergetic effects, when they are used together with antibiotics, for an increased efficiency and less adverse reactions in treatment of bacterial infections. GC-MS (gas chromatography coupled with mass spectrometry), which is considered "the golden standard" in chemical analysis has proven to be a reliable instrument, perfectly suitable for clinical analysis...
July 25, 2017: Journal of Breath Research
https://www.readbyqxmd.com/read/28741297/maldi-ft-icr-ms-for-archaeological-lipid-residue-analysis
#5
Ester Oras, Signe Vahur, Sven Isaksson, Ivari Kaljurand, Ivo Leito
Soft-ionization methods are currently at the forefront of developing novel methods for analysing degraded archaeological organic residues. Here we present little-used soft ionisation method of matrix assisted laser desorption/ionization - Fourier transform - ion cyclotron resonance - mass spectrometry (MALDI-FT-ICR-MS) for the identification of archaeological lipid residues. It is a high-resolution and sensitive method with low limits of detection capable of identifying lipid compounds in small concentrations, thus providing a highly potential new technique for the analysis of degraded lipid components...
July 24, 2017: Journal of Mass Spectrometry: JMS
https://www.readbyqxmd.com/read/28741109/multi-analyte-method-development-for-analysis-of-brominated-flame-retardants-bfrs-and-pbde-metabolites-in-human-serum
#6
Dasheng Lu, Yu'e Jin, Chao Feng, Dongli Wang, Yuanjie Lin, Xinlei Qiu, Qian Xu, Yimin Wen, Jianwen She, Guoquan Wang, Zhijun Zhou
Commonly, analytical methods measuring brominated flame retardants (BFRs) of different chemical polarities in human serum are labor consuming and tedious. Our study used acidified diatomaceous earth as solid-phase extraction (SPE) adsorbent and defatting material to simultaneously determine the most abundant BFRs and their metabolites with different polarities in human serum samples. The analytes include three types of commercial BFRs, tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) isomers, and polybrominated biphenyl ethers (PBDEs), and dominant hydroxylated BDE (OH-PBDE) and methoxylated BDE (MeO-PBDE) metabolites of PBDEs...
July 24, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28741108/automated-clean-up-separation-and-detection-of-polycyclic-aromatic-hydrocarbons-in-particulate-matter-extracts-using-a-2d-lc-2d-gc-system-a-method-translation-from-two-fids-to-two-ms-detectors
#7
Hwanmi Lim, Trifa M Ahmed, Christoffer Bergvall, Roger Westerholm
An online two-dimensional (2D) liquid chromatography/2D gas chromatography system with two mass-selective detectors has been developed on the basis of a previous system with two flame ionization detectors. The method translation involved the change of carrier gas from hydrogen to helium, column dimension and detectors. The 2D system with two mass-selective detectors was validated with use of polycyclic aromatic hydrocarbon (PAH) standards and two standard reference materials from air and diesel exhaust. Furthermore, the system was applied to a real sample, wood smoke particulates...
July 24, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28740828/omega-3-fatty-acids-related-to-cognitive-impairment-in-patients-with-schizophrenia
#8
Kazumi Satogami, Shun Takahashi, Shinichi Yamada, Satoshi Ukai, Kazuhiro Shinosaki
Cognitive impairment is strongly associated with functional outcome in patients with schizophrenia but its pathophysiology remains largely unclear. Involvement of omega-3 fatty acids in the cognitive function of healthy individuals and patients with neuropsychiatric disease has received increasing attention. The aim of this study was to examine the relationship between omega-3 fatty acids with cognitive function, social function, and psychiatric symptoms in patients with schizophrenia. The subjects included 30 patients with schizophrenia or schizoaffective disorder...
September 2017: Schizophrenia Research. Cognition
https://www.readbyqxmd.com/read/28740626/fatty-acids-composition-of-aorta-and-saphenous-vein-tissues-in-patients-with-coronary-artery-diseases
#9
Mirhamid Paytakhti Oskouei, Masoud Pezeshkian, Naser Safaie, Masoud Darabi, Amir Fattahi, Hossain Bijanpour, Maghsod Shaaker, Ahmad Reza Jodati, Mohammad Nouri
Introduction: Considering importance of fatty acids in developing coronary artery disease (CAD) and lack of information about saphenous vein which is commonly used as coronary arterial bypass, in this study we investigated differences in fatty acids composition between saphenous vein and aorta tissues in patients with CAD. Methods: Biopsy samples of aortic tissues and saphenous veins as well as blood samples were obtained form 42 patients with CAD. Fatty acids composition of the tissues was determined using gas chromatography and also serum lipid profile was evaluated by commercial kits...
2017: Journal of Cardiovascular and Thoracic Research
https://www.readbyqxmd.com/read/28738715/antimicrobial-modulatory-and-chemical-analysis-of-the-oil-of-croton-limae
#10
Tiago Rodrigues Leite, Maria Arlene Pessoa da Silva, Antônio Carlito Bezerra Dos Santos, Henrique Douglas Melo Coutinho, Antonia Eliene Duarte, José Galberto Martins da Costa
CONTEXT: Croton sp. are plants with a well-reported antimicrobial activity. Croton limae A.P. Gomes, M.F. Sales P.E. Berry (Euphorbiaceae), known as 'marmeleiro-prateado', is commonly used to manage abdominal pain in Brazil. OBJECTIVE: This work evaluates the phytochemical composition, antimicrobial and modulatory activities of the essential oil of C. limae leaves (EOCL). MATERIALS AND METHODS: The minimum inhibitory concentration (MIC) and the modulation of the antibiotic activity were determined using a microdilution method...
December 2017: Pharmaceutical Biology
https://www.readbyqxmd.com/read/28738652/volatile-composition-of-merlot-red-wine-and-its-contribution-to-the-aroma-optimization-and-validation-of-analytical-method
#11
Stefany Grützmann Arcari, Vinicius Caliari, Marla Sganzerla, Helena Teixeira Godoy
A methodology for the determination of volatile compounds in red wine using headspace solid phase microextraction (HS-SPME) combined with gas chromatography-ion trap/ mass spectrometry (GC-IT/MS) and flame ionization detector (GC -FID) was developed, validated and applied to a sample of Brazilian red wine. The optimization strategy was conducted using the Plackett-Burman design for variable selection and central composite rotational design (CCRD). The response surface methodology showed that the performance of the extraction of the volatile compounds using divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber is improved with no sample dilution, the addition of 30% NaCl, applying an extraction temperature of 56°C and extraction time of 55min...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738648/matrix-interference-evaluation-employing-gc-and-lc-coupled-to-triple-quadrupole-tandem-mass-spectrometry
#12
S Uclés, A Lozano, A Sosa, P Parrilla Vázquez, A Valverde, A R Fernández-Alba
Gas and liquid chromatography coupled to triple quadrupole tandem mass spectrometry are currently the most powerful tools employed for the routine analysis of pesticide residues in food control laboratories. However, whatever the multiresidue extraction method, there will be a residual matrix effect making it difficult to identify/quantify some specific compounds in certain cases. Two main effects stand out: (i) co-elution with isobaric matrix interferents, which can be a major drawback for unequivocal identification, and therefore false negative detections, and (ii) signal suppression/enhancement, commonly called the "matrix effect", which may cause serious problems including inaccurate quantitation, low analyte detectability and increased method uncertainty...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738633/application-of-raman-spectroscopy-for-direct-analysis-of-carlina-acanthifolia-subsp-utzka-root-essential-oil
#13
Maciej Strzemski, Magdalena Wójciak-Kosior, Ireneusz Sowa, Monika Agacka-Mołdoch, Piotr Drączkowski, Dariusz Matosiuk, Łukasz Kurach, Ryszard Kocjan, Sławomir Dresler
Carlina genus plants e.g. Carlina acanthifolia subsp. utzka have been still used in folk medicine of many European countries and its biological activity is mostly associated with root essential oils. In the present paper, Raman spectroscopy (RS) was applied for the first time for evaluation of essential oil distribution in root of C. acnthifolia subsp. utzka and identification of root structures containing the essential oil. Furthermore, RS technique was applied to assess chemical stability of oil during drying of plant material or distillation process...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738625/the-screening-of-organic-matter-in-mineral-and-tap-water-by-uhplc-hrms
#14
Marcos A S Ribeiro, Michael Murgu, Valquíria de Moraes Silva, Alexandra C H F Sawaya, Leomara Floriano Ribeiro, Andre Justi, Eduardo C Meurer
It is highly desirable to screen for a large variety of organic compounds in water. Ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS) can analyse semi-polar to polar organic compounds in tap and mineral water. The use of UHPLC-HRMS is well consolidated for lipidomic, metabolomic and proteomic studies; based on the detection of a very large number of compounds of a variety of organic functions. Water analysis is usually performed by gas chromatography -mass spectrometry (GC-MS) techniques that are efficient for volatile organic compounds...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738595/compound-specific-%C3%AE-13-c-and-%C3%AE-2-h-analysis-of-olive-oil-fatty-acids
#15
Mauro Paolini, Luana Bontempo, Federica Camin
Fatty acids are the most abundant biomolecules in olive oil. In this study, we describe the analytical method developed to measure the δ(13)C, and for the first time, the δ(2)H values of fatty acid methyl esters (FAMEs) extracted from olive oil triglycerides, after base-catalysed transesterification with methanol. The extracted FAMEs are analysed using Gas Chromatography Combustion/Pyrolysis Isotope Ratio Mass Spectrometry (GC-C/Py-IRMS). The method made it possible to obtain baseline separation between the peaks of the main FAMEs (C16, C18, C18:1, C18:2)...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738585/ordered-mesoporous-silica-film-as-a-novel-fiber-coating-for-solid-phase-microextraction
#16
Hui Jiang, Jiansheng Li, Xingru Hu, Jinyou Shen, Xiuyun Sun, Weiqing Han, Lianjun Wang
Ordered mesoporous silica (OMS) film supported on anodized titanium wire was fabricated as a new solid phase microextraction (SPME) fiber for the extraction of chlorophenols (CPs) from aqueous media followed by the determination with gas chromatography flame ionization detection (GC-FID). The supported OMS film was prepared via a solvent evaporation-induced self-assembly approach (EISA) combined with dip-coating technology. Commonly used fragile fused silica fiber was replaced by anodized titanium wire. The coating materials were characterized by N2 adsorption-desorption, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and thermogravimetric (TG) analysis...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738571/determination-of-polycyclic-aromatic-hydrocarbons-in-infant-formula-using-solid-state-urea-clathrate-formation-with-gas-chromatography-tandem-mass-spectrometry
#17
Zoltán Nyiri, Márton Novák, Zsolt Bodai, Noémi Petrovics, Zsuzsanna Eke
An analytical method has been developed for the quantitative determination of the 16 EU priority polycyclic aromatic hydrocarbons (PAHs) in infant formula. Prior to analysis infant formula is subjected to sample preparation including the extraction of PAHs from the sample, transesterification of the triglyceride content of the extract to fatty acid methyl esters (FAMEs), and solid state urea clathrate formation to remove the FAMEs. Measurements were carried out with gas chromatography - tandem mass spectrometry...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738556/development-of-a-new-sample-preparation-method-based-on-liquid-liquid-liquid-extraction-combined-with-dispersive-liquid-liquid-microextraction-and-its-application-on-unfiltered-samples-containing-high-content-of-solids
#18
Mir Ali Farajzadeh, Maryam Abbaspour
A new sample preparation method based on liquid-liquid-liquid extraction combined with dispersive liquid-liquid microextraction followed by gas chromatography-flame ionization detection has been reported for the extraction/preconcentration and determination of trace levels of twelve pesticide residues from different samples with high content of solids without filtration. This method consists of a three-phase system including an aqueous phase (sample solution), acetonitrile, and hexane. The extraction mechanism is based on different affinities of the substances from the sample matrices towards each of the involved phase, which provides a high selectivity to the process...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738555/assessment-of-mercury-speciation-in-feathers-using-species-specific-isotope-dilution-analysis
#19
Marina Renedo, Paco Bustamante, Emmanuel Tessier, Zoyne Pedrero, Yves Cherel, David Amouroux
Seabirds are considered as effective sentinels of environmental marine contamination and their feathers are extensively used as non-lethal samples for contaminant biomonitoring. This tissue represents the main route for mercury (Hg) elimination in seabirds and contains predominantly methylmercury (MeHg). In this work, we developed a robust analytical technique for precise and accurate simultaneous quantification of MeHg, inorganic Hg (iHg) and consequently total Hg (THg), in feathers by gas-chromatography (GC)-ICPMS analyses using species-specific isotope dilution technique...
November 1, 2017: Talanta
https://www.readbyqxmd.com/read/28738554/amperometric-detector-for-gas-chromatography-based-on-a-silica-sol-gel-solid-electrolyte
#20
William H Steinecker, Krzysztof Miecznikowski, Pawel J Kulesza, Zechariah D Sandlin, James A Cox
An electrochemical cell comprising a silica sol-gel solid electrolyte, a working electrode that protrudes into a gas phase, and reference and counter electrodes that contact the solid electrolyte comprises an amperometric detector for gas chromatography. Under potentiostatic conditions, a current related to the concentration of an analyte in the gas phase is produced by its oxidation at the three-phase boundary among the sol-gel, working electrode, and the gas phase. The sol-gel is processed to contain an electrolyte that also serves as a humidistat to maintain a constant water activity even in the presence the gas chromatographic mobile phase...
November 1, 2017: Talanta
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