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GC MS analysis

Elham Aslankoohi, Beatriz Herrera-Malaver, Mohammad Naser Rezaei, Jan Steensels, Christophe M Courtin, Kevin J Verstrepen
Saccharomyces cerevisiae is routinely used yeast in food fermentations because it combines several key traits, including fermentation efficiency and production of desirable flavors. However, the dominance of S. cerevisiae in industrial fermentations limits the diversity in the aroma profiles of the end products. Hence, there is a growing interest in non-conventional yeast strains that can help generate the diversity and complexity desired in today's diversified and consumer-driven markets. Here, we selected a set of non-conventional yeast strains to examine their potential for bread fermentation...
2016: PloS One
Hongtao Guo, Xuyan Niu, Yan Gu, Cheng Lu, Cheng Xiao, Kevin Yue, Ge Zhang, Xiaohua Pan, Miao Jiang, Yong Tan, Hongwei Kong, Zhenli Liu, Guowang Xu, Aiping Lu
Pattern classification is a key approach in Traditional Chinese Medicine (TCM), and it is used to classify the patients for intervention selection accordingly. TCM cold and heat patterns, two main patterns of rheumatoid arthritis (RA) had been explored with systems biology approaches. Different regulations of apoptosis were found to be involved in cold and heat classification in our previous works. For this study, the metabolic profiling of plasma was explored in RA patients with typical TCM cold or heat patterns by integrating liquid chromatography/mass spectrometry (LC/MS) and gas chromatography/mass spectrometry (GC/MS) platforms in conjunction with the Ingenuity Pathway Analysis (IPA) software...
October 21, 2016: International Journal of Molecular Sciences
Liu Tang, Yicun Chen, Zebin Jiang, Shuping Zhong, Weizhou Chen, Fuchun Zheng, Ganggang Shi
Purification, preliminary characterization and bioactivity of polysaccharides from Grateloupia livida (GL) were investigated. Three water-soluble sulfated polysaccharide fractions (GLP-1, GLP-2 and GLP-3) were isolated and purified from the edible and medicinal red seaweed, Grateloupia livida (Harv.) Yamada by DEAE Sepharose CL-6B and Sephadex G-100 column chromatography, and chemical characterization was performed by HPGPC, GC-MS, FT-IR and SEM. In addition, anticoagulant activities were determined by activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT) using normal human plasma in vitro...
October 20, 2016: International Journal of Biological Macromolecules
Yu-Hsuan Chen, Chia-Yu Chang, Wang-Hsien Ding
A simple and effective method for determining short chain chlorinated paraffins (SCCPs) in indoor dust is presented. The method employed a modified vortex-homogenized matrix solid-phase dispersion (VH-MSPD) prior to its detection by gas chromatography - electron-capture negative-ion mass spectrometry (GC-ECNI-MS) operating in the selected-ion-monitoring (SIM) mode. Under the best extraction conditions, 0.1-g of dust sample was dispersed with 0.1-g of silica gel by using vortex (2min) instead of using a mortar and pestle (3min)...
October 19, 2016: Journal of Chromatography. A
Ozkan Acisli, Alireza Khataee, Semra Karaca, Atefeh Karimi, Ercan Dogan
High energy planetary ball milling process was used to prepare magnetite nanostructures from natural magnetite. The natural and ball-milled magnetite samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET) and Fourier transform infrared spectroscopy (FT-IR). The results of EDX indicated the presence of main elements including Fe and O in the structure of both unmodified and milled magnetite samples...
January 2017: Ultrasonics Sonochemistry
Sunita Bijarnia-Mahay, Deepti Gupta, Yosuke Shigematsu, Seiji Yamaguchi, Renu Saxena, I C Verma
BACKGROUND: Ethylmalonic encephalopathy is a rare inborn error of metabolism characterized by neurodevelopmental delay / regression, recurrent petechiae, orthostatic acrocyanosis, and chronic diarrhea. CASE CHARACTERISTICS: 4-year-old boy with developmental regression, chronic diarrhea, petechial spots and acrocyanosis. MRI brain showed T2W/FLAIR hyperintensities in bilateral caudate and putamen. Abnormal acyl-carnitine profile and metabolites on urinary GC-MS analysis suggested the diagnosis...
October 8, 2016: Indian Pediatrics
Larissa Rangel Peixoto, Pedro Luiz Rosalen, Gabriela Lacet Silva Ferreira, Irlan Almeida Freires, Fabíola Galbiatti de Carvalho, Lúcio Roberto Castellano, Ricardo Dias de Castro
OBJECTIVE: The present study demonstrated the antifungal potential of the chemically characterized essential oil (EO) of Laurus nobilis L. (bay laurel) against Candida spp. biofilm adhesion and formation, and further established its mode of action on C. albicans. METHODS: L. nobilis EO was obtained and tested for its minimum inhibitory and fungicidal concentrations (MIC/MFC) against Candida spp., as well as for interaction with cell wall biosynthesis and membrane ionic permeability...
October 18, 2016: Archives of Oral Biology
R Tafer, M Sleiman, A Boulkamh, C Richard
The photolysis of aqueous 5-chlorosalicylic acid (ClSA) and dihydroxybenzoic acid (DHBA), its main photoproduct, was studied to determine the extent of degradation caused by simulated solar light. Photoproducts identification was achieved using high resolution LC-MS and GC-MS. About 40 photoproducts from C19 to C1 were characterized, including a dihydroxycyclopentadienic acid, a ring contraction photoproduct, and numerous carbonyls and carboxylic acid derivatives that were detected thanks to derivatization...
October 15, 2016: Water Research
Alexandra Kodadová, Zuzana Vitková, Jarmila Oremusová, Petra Herdová, Anton Ťažký, Peter Mikuš
This work was aimed at a progressive formulation of drugs into chitosan hydrogels. It was taken into consideration that a therapeutic effect of the drugs could be enhanced by a combination of natural compounds with chemical (synthetic) drugs. In this work, sage essential oil (SEO) bicyclic monoterpenes with antiflogistic, antiseptic, and antimycotic properties were combined with terbinafine (TB) having a strong antimycotic activity. Detail optimization of the hydrogel-drugs composition (SEO monoterpenes, TB, chitosan, and polysorbate 80 concentrations), based on permeation experiment and UV absorption/GC-MS analysis of permeated species (eucalyptol, camphor, borneol, thujone, TB) in dialysates, was made...
October 22, 2016: Zeitschrift Für Naturforschung. C, A Journal of Biosciences
Ali Reza Fardin-Kia
Non-conjugated geometric/positional isomers of linoleic acid (c9,c12-18:2) are often present in processed foods and oils. The following work presents a simple addition/elimination reaction for preparation of non-conjugated 18:2 fatty acid isomers. A mixture containing positional and geometric isomers of C18:2 fatty acids was produced by addition of hydrobromic acid to the fatty acid double bonds, followed by its elimination with a strong sterically hindered base. Pure 8,12-, 8,13-, 9,12-, and 9,13-18:2 fatty acid methyl esters were isolated from the synthetic mixture by a combination of sub-ambient RP-HPLC and Ag(+)-HPLC...
October 18, 2016: Chemistry and Physics of Lipids
Ji Ye Lee, Na Hyun Park, Wonwoong Lee, Eun Hye Kim, Young Ho Jin, Eun Kyung Seo, Jongki Hong
A comprehensive profiling method was established for the determination of various chemicals in Pinellia (P.) ternata and pedatisecta species. The profiling method comprises a fast ultrasonic extraction with various solvents, followed by GC-MS and LC-APCI-MS analysis. A total of 73 polar components as trimethylsilyl (TMS) derivatives were detected in methanol extract by GC-MS. The main components of the P. species were profiled as several kinds of fatty acids, amino acids, nucleic acids, carbohydrates, and phenolic compounds...
October 13, 2016: Journal of Chromatography. A
Gabrieli Bernardi, Magali Kemmerich, Lucila C Ribeiro, Martha B Adaime, Renato Zanella, Osmar D Prestes
An effective method has been developed and validated for the determination of residues of 55 pesticides in tobacco. The proposed sample preparation method is based on acetonitrile extraction, low-temperature precipitation (LTP) and dispersive solid phase extraction (d-SPE) clean-up. Gas chromatography and ultra-high performance liquid chromatography analysis, both coupled to tandem mass spectrometry (GC-MS/MS and UHPLC-MS/MS), were used for determination. LTP is easy to perform and was crucial to obtain a clean extract...
December 1, 2016: Talanta
Michael S Gross, Hernando J Olivos, Deena M Butryn, James R Olson, Diana S Aga
Hydroxylated polybrominated diphenyl ethers (OH-BDEs), which have anthropogenic and natural origins, have exhibited neurotoxic and endocrine disrupting effects in humans and wildlife. Therefore, there is an increased interest in the analysis of these compounds in biological matrices in order to assess their potential toxicological risks. Analysis of OH-BDEs is conventionally completed using liquid chromatography/mass spectrometry (LC/MS), or by gas chromatography/mass spectrometry (GC/MS) after derivatization...
December 1, 2016: Talanta
Rui Yang, Yuxin Liu, Xiangyang Yan, Shaomin Liu
A rapid, sensitive and accurate method for the simultaneous extraction and determination of five types of trace phthalate esters (PAEs) in environmental water and beverage samples using magnetic molecularly imprinted solid-phase extraction (MMIP-SPE) coupled with gas chromatography-mass spectrometry (GC-MS) was developed. A novel type of molecularly imprinted polymers on the surface of yolk-shell magnetic mesoporous carbon (Fe3O4@void@C-MIPs) was used as an efficient adsorbent for selective adsorption of phthalate esters based on magnetic solid-phase extraction (MSPE)...
December 1, 2016: Talanta
Paramee Kumkrong, Benjaporn Thiensong, Phuong Mai Le, Garnet McRae, Anthony Windust, Suladda Deawtong, Juris Meija, Paulette Maxwell, Lu Yang, Zoltán Mester
Methods based on species specific isotope dilution were developed for the accurate and SI traceable determination of arsenobetaine (AsBet) and methylmercury (MeHg) in prawn and cuttlefish tissues by LC-MS/MS and SPME GC-ICPMS. Quantitation of AsBet and MeHg were achieved by using a (13)C-enriched AsBet spike (NRC CRM CBET-1) and an enriched spike of Me(198)Hg (NRC CRM EMMS-1), respectively, wherein analyte mass fractions in enriched spikes were determined by reverse isotope dilution using natural abundance AsBet and MeHg primary standards...
November 2, 2016: Analytica Chimica Acta
Nadia G Kandile, Mansoura I Mohamed, Hind M Ismaeel
New compounds based on oxindole moiety were synthesized via the reaction of 5-substitued isatins 1a-e with different nucleophiles such as benzidine, 3,3'-dimethoxybenzidine 2a,b and 2,6-diaminopyridine 3 to afford three different classes of bis-Schiff bases 4a-e, 5a-e and 6a-e, respectively. The structures of the new compounds were elucidated on the basis of their FTIR, (1)H NMR, (13)C NMR, GC/MS spectral data and elemental analysis. The in vitro antimicrobial activity of the new compounds was evaluated using a broth dilution technique in terms of minimal inhibitory concentration (MIC) against four bacterial and two fungal pathogens and anticancer activities against HELA cervix...
October 21, 2016: Journal of Enzyme Inhibition and Medicinal Chemistry
John J Guardiola, Juliane I Beier, K Cameron Falkner, Benjamin Wheeler, Craig James McClain, Matt Cave
BACKGROUND: Occupational vinyl chloride (VC) exposures have been associated with toxicant-associated steatohepatitis and liver cancer. Metabolomics has been used to clarify mode of action in drug-induced liver injury but has not been performed following VC exposures. METHODS: Plasma samples from 17 highly exposed VC workers without liver cancer and 27 unexposed healthy volunteers were obtained for metabolite extraction and GC/MS and LC/MS(2) analysis. Following ion identification/quantification, Ingenuity pathway analysis was performed...
October 17, 2016: Toxicology and Applied Pharmacology
Lêniféré Chantal Soro, Sylvie Munier, Yves Pelissier, Lidwine Grosmaire, Rickey Yada, David Kitts, Anin Louise Ocho-Anin Atchibri, Caroline Guzman, Frédéric Boudard, Chantal Menut, Jean Charles Robinson, Patrick Poucheret
ETHNOPHARMACOLOGICAL RELEVANCE: Lippia multiflora is a plant with nutritional and pharmaco-therapeutic properties that is native to central and occidental Africa. The potential effects of plants on health are associated with their chemical composition. Therefore, the present study aimed to identify chemical variations in essential oils of Lippia multiflora as a function of geographic origin and time of annual harvest to determine optimal chemical profiles for ethno-pharmacotherapeutic applications...
October 17, 2016: Journal of Ethnopharmacology
Ramona Bosse Née Danz, Melanie Wirth, Annette Konstanz, Thomas Becker, Jochen Weiss, Monika Gibis
A simple, reliable and automated method was developed and optimized for qualification and quantification of aroma-relevant volatile marker compounds of North European raw ham using a headspace (HS)-Trap gas chromatography-mass spectrometry (GC-MS) and GC-flame ionization detector (FID) analysis. A total of 38 volatile compounds were detected with this HS-Trap GC-MS method amongst which the largest groups were ketones (12), alcohols (8), hydrocarbons (7), aldehydes (6) and esters (3). The HS-Trap GC-FID method was optimized for the parameters: thermostatting time and temperature, vial and desorption pressure, number of extraction cycles and salt addition...
March 15, 2017: Food Chemistry
Thais M Uekane, Luca Nicolotti, Alessandra Griglione, Humberto R Bizzo, Patrizia Rubiolo, Carlo Bicchi, Maria Helena M Rocha-Leão, Claudia M Rezende
The volatile fraction of murici, bacuri and sapodilla are here studied because of their increasing interest for consumers, abundance of production in Brazil, and the general demand for new flavors and aromas. Their volatile profiles were studied by two High Concentration Capacity Headspace techniques (HCC-HS), Headspace Solid Phase Microextraction (HS-SPME) and Headspace Sorptive Extraction (HSSE), in combination with GC-MS. Murici volatile fraction mainly contains esters (38%), carboxylic acids (19%), aldehydes (11%), alcohols (14%), others (13%) and sulfur compounds; bacuri is characterized by terpenes (41%), non-terpenic alcohols (24%), esters (15%), aldehydes (6%), and others (12%); sapodilla consists of esters (33%), alcohols (27%), terpenes (18%) and others (21%)...
March 15, 2017: Food Chemistry
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