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https://www.readbyqxmd.com/read/28087213/cholesterolomics-an-update
#1
William J Griffiths, Jonas Abdel-Khalik, Eylan Yutuc, Alwena H Morgan, Ian Gilmore, Thomas Hearn, Yuqin Wang
Cholesterolomics can be regarded as the identification and quantification of cholesterol, its precursors post squalene, and metabolites of cholesterol and of its precursors, in a biological sample. These molecules include 1,25-dihydroxyvitamin D3, steroid hormones and bile acids and intermediates in their respective biosynthetic pathways. In this short article we will concentrate our attention on intermediates in bile acid biosynthesis pathways, in particular oxysterols and cholestenoic acids. These molecular classes are implicated in the aetiology of a diverse array of diseases including autoimmune disease, Parkinson's disease, motor neuron disease, breast cancer, the lysosomal storage disease Niemann-Pick type C and the autosomal recessive disorder Smith-Lemli-Opitz syndrome...
January 10, 2017: Analytical Biochemistry
https://www.readbyqxmd.com/read/28079180/the-herbivore-induced-plant-volatiles-methyl-salicylate-and-menthol-positively-affect-growth-and-pathogenicity-of-entomopathogenic-fungi
#2
Yongwen Lin, Muhammad Qasim, Mubasher Hussain, Komivi Senyo Akutse, Pasco Bruce Avery, Chandra Kanta Dash, Liande Wang
Some herbivore-induced-plant volatiles (HIPVs) compounds are vital for the functioning of an ecosystem, by triggering multi-trophic interactions for natural enemies, plants and herbivores. However, the effect of these chemicals, which play a crucial role in regulating the multi-trophic interactions between plant-herbivore-entomopathogenic fungi, is still unknown. To fill this scientific gap, we therefore investigated how these chemicals influence the entomopathogenic fungi growth and efficacy. In this study, Lipaphis erysimi induced Arabidopsis thaliana HIPVs were collected using headspace system and detected with GC-MS, and then analyzed the effects of these HIPVs chemicals on Lecanicillium lecanii strain V3450...
January 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28078517/semivolatile-organic-compounds-in-surface-microlayer-and-subsurface-water-of-dianshan-lake-shanghai-china-implications-for-accumulation-and-interrelationship
#3
Ming-Hong Wu, Xue-Xia Yang, Gang Xu, Chen-Jing Que, Si-Han Ma, Liang Tang
Semivolatile organic compounds (SVOCs) in surface microlayer (SML) and subsurface water (SSW) from Dianshan Lake were studied to investigate their occurrence, distributions, as well as enrichment and potential sources. A sample was concentrated by solid-phase micro-extraction (SPME). Identification and quantification were carried out by gas chromatography coupled to mass spectrometry (GC-MS). Total SVOCs concentrations ranged from 25.93 to 47.49 μg/L in SSW and 38.19 to 77.23 μg/L in SML. The phthalic acid esters (PAE) concentrations in both SSW and SML are the highest of the total SVOC...
January 11, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28078415/gc-ms-method-validation-and-levels-of-methyl-eugenol-in-a-diverse-range-of-tea-tree-melaleuca-alternifolia-oils
#4
Carolyn A Raymond, Noel W Davies, Tony Larkman
Tea tree oil distilled from Melaleuca alternifolia has widespread use in the cosmetic industry as an antimicrobial as well as for other functions in topical products. Concerns were first raised by the European Commission's Scientific Committee on Consumer Products in 2004 about the level of the potentially carcinogenic phenylpropanoid compound methyl eugenol in tea tree oil. Limits on oil content in different types of cosmetic products were set based on a reported upper level of 0.9% methyl eugenol in the oil...
January 11, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28078414/application-of-hs-spme-gc-ms-method-for-the-detection-of-active-moulds-on-historical-parchment
#5
Tomasz Sawoszczuk, Justyna Syguła-Cholewińska, Julio M Del Hoyo-Meléndez
The goal of this work was to analyse the profile of microbial volatile organic compounds (MVOCs) emitted by moulds growing on parchment samples, in search of particular volatiles mentioned in the literature as indicators of active mould growth. First, the growth of various moulds on samples of parchment was assessed. Those species that showed collagenolytic activity were then inoculated on two types of media: samples of parchment placed on media and on media containing amino acids that are elements of the structure of collagen...
January 11, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28078400/characterization-of-four-endophytic-fungi-as-potential-consolidated-bioprocessing-hosts-for-conversion-of-lignocellulose-into-advanced-biofuels
#6
Weihua Wu, Ryan W Davis, Mary Bao Tran-Gyamfi, Alan Kuo, Kurt LaButti, Sirma Mihaltcheva, Hope Hundley, Mansi Chovatia, Erika Lindquist, Kerrie Barry, Igor V Grigoriev, Bernard Henrissat, John M Gladden
Recently, several endophytic fungi have been demonstrated to produce volatile organic compounds (VOCs) with properties similar to fossil fuels, called "mycodiesel," while growing on lignocellulosic plant and agricultural residues. The fact that endophytes are plant symbionts suggests that some may be able to produce lignocellulolytic enzymes, making them capable of both deconstructing lignocellulose and converting it into mycodiesel, two properties that indicate that these strains may be useful consolidated bioprocessing (CBP) hosts for the biofuel production...
January 12, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28076838/identification-of-mdmb-fubinaca-in-commercially-available-e-liquid-formulations-sold-for-use-in-electronic-cigarettes
#7
Michelle R Peace, Rose I Krakowiak, Carl E Wolf, Alphonse Poklis, Justin L Poklis
MDMB-FUBINACA (aka MDMB(N)-Bz-F), chemical name Methyl (S)-2-(1-(4-fluorobenzyl)-1H-indazole-3-carboxamido)-3,3-dimethylbutanoate, a designer drug or a new psychoactive substance (NPS), was identified in three commercially available e-liquids formulated for electronic cigarette use. The e-liquids were evaluated using direct analysis in real time ion source attached to a time of flight mass spectrometer (DART-MS) and gas chromatograph mass spectrometer (GC-MS) to identify active ingredients/drugs, flavorants, and other possible constituents...
December 27, 2016: Forensic Science International
https://www.readbyqxmd.com/read/28075566/chilling-stress-upregulates-%C3%AE-linolenic-acid-oxidation-pathway-and-induces-volatiles-of-c6-and-c9-aldehydes-in-mango-fruit
#8
Velu Sivankalyani, Itay Maoz, Oleg Feygenberg, Dalia Maurer, Noam Alkan
Mango-fruit storage period and shelf life are prolonged by cold storage. However, chilling temperature induces physiological and molecular changes, compromising fruit quality. In our previous transcriptomic study of mango fruit, cold storage at suboptimal temperature (5 °C) activated the α-linolenic acid metabolic pathway. To evaluate changes in fruit quality during chilling, we analyzed mango "Keitt" fruit peel volatiles. GC-MS analysis revealed significant modulations in fruit volatiles during storage at suboptimal temperature...
January 11, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28075408/time-course-exo-metabolomic-profiling-in-the-green-marine-macroalga-ulva-chlorophyta-for-identification-of-growth-phase-dependent-biomarkers
#9
Taghreed Alsufyani, Anne Weiss, Thomas Wichard
The marine green macroalga Ulva (Chlorophyta) lives in a mutualistic symbiosis with bacteria that influence growth, development, and morphogenesis. We surveyed changes in Ulva's chemosphere, which was defined as a space where organisms interact with each other via compounds, such as infochemicals, nutrients, morphogens, and defense compounds. Thereby, Ulva mutabilis cooperates with bacteria, in particular, Roseovarius sp. strain MS2 and Maribacter sp. strain MS6 (formerly identified as Roseobacter sp. strain MS2 and Cytophaga sp...
January 10, 2017: Marine Drugs
https://www.readbyqxmd.com/read/28073941/prognostic-roles-of-tetrahydroxy-bile-acids-in-infantile-intrahepatic-cholestasis
#10
Chee-Seng Lee, Akihiko Kimura, Jia-Feng Wu, Yen-Hsuan Ni, Hong-Yuan Hsu, Mei-Hwei Chang, Hiroshi Nittono, Huey-Ling Chen
Tetrahydroxy bile acids (THBAs) are hydrophilic and are present at minimal or undetectable levels in healthy human adults but are present at high levels in bile salt export pump (abcb11)-knockout mice. The roles of THBAs in human cholestatic diseases are unclear. We aimed to investigate the presence of THBAs in patients with infantile intrahepatic cholestasis and its correlation with outcome. Urinary bile acids were analysed by GC-MS. Data were compared between good (N=21) (disease-free before 1 year old) and poor prognosis groups (N=19)...
January 10, 2017: Journal of Lipid Research
https://www.readbyqxmd.com/read/28073452/characterization-of-cyclitol-glycosides-by-gas-chromatography-coupled-to-mass-spectrometry
#11
L Ruiz-Aceituno, C Carrero-Carralero, A I Ruiz-Matute, L Ramos, M L Sanz, I Martínez-Castro
Several cyclitol glycosides have been characterised as trimethylsilyl derivatives by their gas chromatographic (GC) retention data (linear retention indices) and electron impact mass spectrometric (MS) profiles. Both GC-MS results have been related to cyclitol glycosides structural features. Abundance ratios of characteristic m/z ions 133/129 and 260/265 have been proposed to distinguish glycosyl-inositols from glycosyl-methyl-inositols. These ratios in combination with the presence or absence of m/z 375 ion allowed the unequivocal characterization of cyclitol glycosides...
January 3, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28073348/wild-carrot-pentane-based-fractions-suppress-proliferation-of-human-hacat-keratinocytes-and-protect-against-chemically-induced-skin-cancer
#12
Wassim N Shebaby, Mohamad A Mroueh, Petra Boukamp, Robin I Taleb Ri, Kikki Bodman-Smith, Mirvat El-Sibai, Costantine F Daher
BACKGROUND: Previous studies in our laboratory showed that the Lebanese Daucus carota ssp. carota (wild carrot) oil extract possesses in vitro and in vivo anticancer activities. The present study aims to examine the cytotoxic effect of Daucus carota oil fractions on human epidermal keratinocytes and evaluate the chemopreventive activity of the pentane diethyl ether fraction on DMBA/TPA induced skin carcinogenesis in mice. METHODS: Wild carrot oil extract was chromatographed to yield four fractions (F1, 100% pentane; F2, 50:50 pentane:diethyl ether; F3, 100% diethyl ether; F4 93:7 chloroform:methanol)...
January 10, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28071000/chemical-composition-and-antioxidant-activities-of-essential-oils-from-different-parts-of-the-oregano
#13
Fei Han, Guang-Qiang Ma, Ming Yang, Li Yan, Wei Xiong, Ji-Cheng Shu, Zhi-Dong Zhao, Han-Lin Xu
This research was undertaken in order to characterize the chemical compositions and evaluate the antioxidant activities of essential oils obtained from different parts of the Origanum vulgare L. It is a medicinal plant used in traditional Chinese medicine for the treatment of heat stroke, fever, vomiting, acute gastroenteritis, and respiratory disorders. The chemical compositions of the three essential oils from different parts of the oregano (leaves-flowers, stems, and roots) were identified by gas chromatography-mass spectrometry (GC-MS)...
2017: Journal of Zhejiang University. Science. B
https://www.readbyqxmd.com/read/28070799/metabolic-alterations-and-the-protective-effect-of-punicalagin-against-glutamate-induced-oxidative-toxicity-in-ht22-cells
#14
Kavitha Pathakoti, Lavanya Goodla, Manjunath Manubolu, Tewin Tencomnao
Oxidative stress is involved in many neurological diseases, including Alzheimer's disease. Punicalagin (PC) is a hydrolysable polyphenol derived from Punica granatum and a potent antioxidant. In this study, the neuroprotective effect of PC on glutamate-induced oxidative stress was evaluated in the mouse hippocampal cell line, HT22. PC treatment protected HT22 cells from glutamate-induced cell death in a concentration-dependent manner, potentially attenuated glutamate-induced intracellular reactive oxygen species (ROS) and restored the mitochondrial membrane depolarization...
January 9, 2017: Neurotoxicity Research
https://www.readbyqxmd.com/read/28069869/determination-of-%C3%A2-9-tetrahydrocannabinol-thc-11-hydroxy-thc-11-nor-9-carboxy-thc-and-cannabidiol-in-human-plasma-using-gas-chromatography-tandem-mass-spectrometry
#15
David M Andrenyak, David E Moody, Matthew H Slawson, Daniel S O'Leary, Margaret Haney
Two marijuana compounds of particular medical interest are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). A gas chromatography-tandem mass spectrometry (GC-MS-MS) method was developed to test for CBD, THC, hydroxy-THC (OH-THC) and carboxy-THC (COOH-THC) in human plasma. Calibrators (THC and OH-THC, 0.1 to 100; CBD, 0.25 to 100; COOH-THC, 0.5-500 ng/mL) and controls (0.3, 5 and 80 ng/mL, except COOH-THC at 1.5, 25 and 400 ng/mL) were prepared in blank matrix. Deuterated (d3) internal standards were added to 1-mL samples...
January 8, 2017: Journal of Analytical Toxicology
https://www.readbyqxmd.com/read/28069166/evaluation-and-prevention-of-the-negative-matrix-effect-of-terpenoids-on-pesticides-in-apples-quantification-by-gas-chromatography-tandem-mass-spectrometry
#16
Géraldine Giacinti, Christine Raynaud, Sophie Capblancq, Valérie Simon
The sample matrix can enhance the gas chromatography signal of pesticide residues relative to that obtained with the same concentration of pesticide in solvent. This paper is related to negative matrix effects observed in coupled gas chromatography-mass spectrometry ion trap (GC/MS(2)) quantification of pesticides in concentrated extracts of apple peel prepared by the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method. It is focused on the pesticides most frequently used on the apple varieties studied, throughout the crop cycle, right up to harvest, to combat pests and diseases and to improve fruit storage properties...
December 21, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28068844/hierarchical-cluster-analysis-and-chemical-characterisation-of-myrtus-communis-l-essential-oil-from-yemen-region-and-its-antimicrobial-antioxidant-and-anti-colorectal-adenocarcinoma-properties
#17
Sirajudheen Anwar, Rebecca A Crouch, Nasser A Awadh Ali, Mohamed A Al-Fatimi, William N Setzer, Ludger Wessjohann
The hydrodistilled essential oil obtained from the dried leaves of Myrtus communis, collected in Yemen, was analysed by GC-MS. Forty-one compounds were identified, representing 96.3% of the total oil. The major constituents of essential oil were oxygenated monoterpenoids (87.1%), linalool (29.1%), 1,8-cineole (18.4%), α-terpineol (10.8%), geraniol (7.3%) and linalyl acetate (7.4%). The essential oil was assessed for its antimicrobial activity using a disc diffusion assay and resulted in moderate to potent antibacterial and antifungal activities targeting mainly Bacillus subtilis, Staphylococcus aureus and Candida albicans...
January 9, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28067464/analysis-of-six-neuro-enhancing-phenidate-analogs
#18
Helge Klare, Jörg M Neudörfl, Simon D Brandt, Elisabeth Mischler, Sigrid Meier-Giebing, Kathrin Deluweit, Folker Westphal, Tim Laussmann
Six collected phenidates, i.e. 4-methylmethylphenidate, 3,4-dichloromethylphenidate, ethylphenidate, 3,4-dichloroethylphenidate, ethylnaphthidate and N-benzyl-ethylphenidate were fully characterized by means of X-ray, NMR, GC-MS, ESI-MS(2) , ATR-FT-IR and GC solid-state IR analysis. Crystallography revealed the exclusive presence of the threo-configuration. Steric crowding induced by N-benzyl substitution at the piperidine moiety prompted an adoption of an unexpected axial positioning of substituents on the piperidine moiety in the crystal state as opposed to the exclusive equatorial positioning encountered in N-unsubstituted phenidate analogs...
January 9, 2017: Drug Testing and Analysis
https://www.readbyqxmd.com/read/28067117/furan-in-commercial-baby-foods-from-the-spanish-market-estimation-of-daily-intake-and-risk-assessment
#19
M S Altaki, F J Santos, L Puignou, M T Galceran
The occurrence of furan in commercial baby food samples from the Spanish market was evaluated using an automated headspace solid-phase microextraction method coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS). A total of seventy six baby food samples including infant formula, baby cereals, fruit in cans and/or jars, vegetables, meat, and fish, were surveyed for furan content. The lowest concentration of this compound was found in infant formula (<0.02 - 0.33 ng mL(-1)), and cereal-based food (0...
January 9, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28067067/chemical-composition-antimicrobial-antioxidant-and-anthocyanin-activities-of-mosses-cinclidotus-fontinaloides-hedw-p-beauv-and-palustriella-commutata-hedw-ochyra-gathered-from-turkey
#20
Ozlem Tonguc Yayintas, Duygu Alpaslan, Yonca Karagul Yuceer, Selehattin Yilmaz, Nurettin Sahiner
Cinclidotus fontinaloides (Hedw.) P. Beauv. and Palustriella commutata (Hedw.) Ochyra were used in this study. The chemical composition of mosses in the ethanol and water extract was determined using GC-MS and FT-IR. Antioxidant activities of moss extracts were tested by total phenol and ABTS methods. Trolox equivalent value (TEAC) of mosses was calculated as 26 ± 0.32 and 10 ± 0.22 mg/g. The amounts of the flavonoid compounds were calculated as mg gallic acid. Gallic acid equivalent value of mosses was calculated as 587 ± 0...
January 9, 2017: Natural Product Research
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