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https://www.readbyqxmd.com/read/28103489/enhanced-degradation-of-organic-contaminants-in-water-by-peroxydisulfate-coupled-with-bisulfite
#1
Chengdu Qi, Xitao Liu, Yang Li, Chunye Lin, Jun Ma, Xiaowan Li, Huijuan Zhang
In this study, the bisulfite-peroxydisulfate system (S(IV)/PDS) widely used in polymerization was innovatively applied for organic contaminants degradation in water. The addition of S(IV) into PDS system remarkably enhanced the degradation efficiency of bisphenol A (BPA, a frequently detected endocrine disrupting chemical in the environments) from 17.0% to 84.7% within 360 min. The degradation efficiency of BPA in the S(IV)/PDS system followed pseudo-first-order kinetics, with rate constant values ranging from 0...
January 10, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28103258/revisiting-greek-propolis-chromatographic-analysis-and-antioxidant-activity-study
#2
Konstantinos M Kasiotis, Pelagia Anastasiadou, Antonis Papadopoulos, Kyriaki Machera
Propolis is a bee product that has been extensively used in alternative medicine and recently has gained interest on a global scale as an essential ingredient of healthy foods and cosmetics. Propolis is also considered to improve human health and to prevent diseases such as inflammation, heart disease, diabetes and even cancer. However, the claimed effects are anticipated to be correlated to its chemical composition. Since propolis is a natural product, its composition is consequently expected to be variable depending on the local flora alignment...
2017: PloS One
https://www.readbyqxmd.com/read/28102075/molecular-features-of-humic-acids-and-fulvic-acids-from-contrasting-environments
#3
Judith Schellekens, Peter Buurman, Karsten Kalbitz, Andre van Zomeren, Pablo Vidal-Torrado, Chiara Cerli, Rob N J Comans
Insight in the molecular structure of humic acid (HA) and fulvic acid (FA) can contribute to identify relationships between their molecular properties, and further our quantitative abilities to model important organic matter functions such as metal complexation and association with mineral surfaces. Pyrolysis gas chromatography/mass spectrometry (Py-GC-MS) is used to compare the molecular composition of HA and FA. A systematic comparison was obtained by using samples from different environmental sources, including solid and aqueous samples from both natural and waste sources...
January 19, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28101114/dietary-and-socio-demographic-determinants-of-serum-persistent-organic-pollutants-pops-levels-in-pregnant-women-in-tehran
#4
Bita Eslami, Batool Hossein-Rashidi, Kazem Naddafi, Noushin Rastkari, Abolghasem Djazayeri, Hossein Malekafzali
Objective: To determine the levels of Polychlorinated biphenyls (PCBs) and Polybrominateddiphenyl ethers (PBDEs) as persistent organic pollutants (POPs) in serum of primiparous women at the third trimester of pregnancy and identify the main determinants of POPs levels such as socio-demographic, lifestyle, and diet in Tehran. Materials and methods: One- hundred eighty five serum samples from two simultaneous case-control studies were collected from September 2013 until August 2015.Ten most abundant PCB congeners (International Union of Pure and Applied Chemistry (IUPAC) congeners 28, 52, 74, 99, 101, 118, 138, 153, 180 and 187) as well as eight PBDE congeners (IUPAC congeners 28, 47, 99, 100, 153, 154, 183 and 209)were analyzed by Gas Chromatography Mass Spectrometry (GC/MS)...
September 2016: Journal of Family & Reproductive Health
https://www.readbyqxmd.com/read/28100886/characterization-of-volatile-compounds-with-hs-spme-from-oxidized-n-3-pufa-rich-oils-via-rancimat-tests
#5
Kai-Min Yang, Ming-Ching Cheng, Chih-Wei Chen, Chin-Yin Tseng, Li-Yun Lin, Po-Yuan Chiang
Algae oil and fish oil are n-3 PUFA mainstream commercial products. The various sources for the stability of n-3 PUFA oxidation are influenced by the fatty acid composition, extraction and refined processing. In this study, the oil stability index (OSI) occurs within 2.3 to 7.6 hours with three different n-3 PUFA rich oil. To set the OSI in the Rancimat test as the oil stability limit and observed various degrees of oxidation (0, 25, 50, 75, 100 and 125%). The volatile oxidation compounds were analyzed via headspace-solid phase microextraction (HS-SPME) and GC/MS...
January 18, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/28098995/a-chemometrics-approach-to-the-investigation-of-the-intraspecific-variability-of-the-volatile-oil-of-eupatorium-tremulum-from-southern-brazil
#6
Tiago J T de Souza, Sérgio A L Bordignon, Miriam A Apel
Eupatorium tremulum is a South American shrub reported to cause cattle digestive intoxication, of which the volatile oil, mainly composed by bisabolane- and amorphane-type sesquiterpenoids, exhibits high quantitative variability. This report describes the application of chemometric tools for the identification of volatile compounds that characterize phenophasical changes in the plant. Preblooming, blooming, and postblooming specimens were paired-sampled and submitted to hydrodistillation and GC-MS analysis...
January 18, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/28098834/volatile-compound-profiling-by-hs-spme-gc-ms-fid-of-a-core-olive-cultivar-collection-as-a-tool-for-aroma-improvement-of-virgin-olive-oil
#7
Lourdes García-Vico, Angjelina Belaj, Araceli Sánchez-Ortiz, José M Martínez-Rivas, Ana G Pérez, Carlos Sanz
Virgin olive oil (VOO) is the only food product requiring official sensory analysis to be classified in commercial categories, in which the evaluation of the aroma plays a very important role. The selection of parents, with the aim of obtaining new cultivars with improved oil aroma, is of paramount importance in olive breeding programs. We have assessed the volatile fraction by headspace-solid-phase microextraction/gas chromatography-mass spectrometry-flame ionization detection (HS-SPME/GC-MS-FID) and the deduced aroma properties of VOO from a core set of olive cultivars (Core-36) which possesses most of the genetic diversity found in the World Olive Germplasm Collection (IFAPA Alameda del Obispo) located in Cordoba, Spain...
January 14, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28093672/influence-of-quechers-modifications-on-recovery-and-matrix-effect-during-the-multi-residue-pesticide-analysis-in-soil-by-gc-ms-ms-and-gc-ecd-npd
#8
Bożena Łozowicka, Ewa Rutkowska, Magdalena Jankowska
A QuEChERS extraction followed by GC/MS/MS and GC-μECD/NPD for 216 pesticide and metabolites determination in soil simultaneously were developed and compared. Volume of water, volume and polarity of solvent, and cleanup sorbents (C18, GCB, PSA) were optimized. The QuEChERS with and without purification step were applied to estimate effectiveness of the method. The recovery and matrix effect (ME) were critical parameters within each tested procedure. The optimal method without cleanup was validated. Accuracy (expressed as recovery), precision (expressed as RSD), linearity, LOQ, and uncertainty were determined...
January 16, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28092007/study-of-the-genotoxicity-of-organic-extracts-from-wastewater-irrigated-vegetables-using-in-vitro-and-in-vivo-biological-tests
#9
Hongxia Gao, Yanhua Cao, Yingli Liu, Nan Liu, Weijun Guan
The purpose of this study was to explore genotoxicity due to organic pollutants in wastewater-irrigated vegetables using biological and chemical analyses. Chinese cabbages from wastewater-irrigated farmland were taken as the research object. For the in vitro test, DNA damage was characterized in rat hepatocytes exposed to organic extracts from the cabbages using the comet assay. For the in vivo tests, mice were exposed to organic extracts from the cabbages. DNA damage was assessed in mouse peripheral blood lymphocytes (PBLs), and chromosome damage was assessed in bone marrow cells using the comet assay and micronucleus test, respectively...
January 16, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28089927/metabolism-of-selective-20-epi-vitamin-d3-analogs-in-rat-osteosarcoma-umr-106-cells-isolation-and-identification-of-four-novel-c-1-fatty-acid-esters-of-1%C3%AE-25-dihydroxy-16-ene-20-epi-vitamin-d3
#10
Caroline Ceailles Flarakos, Andrew Weiskopf, Matthew Robinson, Guoshun Wang, Paul Vouros, Gino J Sasso, Milan R Uskokovic, G Satyanarayana Reddy
Analogs of 1α,25-dihydroxyvitamin D3 (S1) with 20-epi modification (20-epi analogs) possess unique biological properties. We previously reported that 1α,25-dihydroxy-20-epi-vitamin D3 (S2), the basic 20-epi analog is metabolized into less polar metabolites (LPMs) in rat osteosarcoma cells (UMR-106) but not in a perfused rat kidney. Furthermore, we also noted that only selective 20-epi analogs are metabolized into LPMs. For example, 1α,25-dihydroxy-16-ene-20-epi-vitamin D3 (S4), but not 1α,25-dihydroxy-16-ene-23-yne-20-epi-vitamin D3 (S5) is metabolized into LPMs...
January 12, 2017: Steroids
https://www.readbyqxmd.com/read/28089716/a-characterization-of-the-antimalarial-activity-of-the-bark-of-cylicodiscus-gabunensis-harms
#11
Omar Aldulaimi, Fidelia I Uche, Hamza Hameed, Haddijatou Mbye, Imran Ullah, Falko Drijfhout, Timothy D W Claridge, Paul Horrocks, Wen-Wu Li
ETHNOPHARMACOLOGICAL RELEVANCE AND AIM: A decoction of the bark of Cylicodiscus gabunensis Harms is used as a traditional medicine in the treatment of malaria in Nigeria. This study aims to validate the antimalarial potency of this decoction in vitro against Plasmodium falciparum and define potential bioactive constituents within the C. gabunensis bark. MATERIALS AND METHODS: A bioassay-guided separation and fractionation protocol was applied to C. gabunensis extracts, exploiting the use of a Malaria Sybr Green I Fluorescence assay method to monitor antiproliferative effects on parasites as well as define 50% inhibition concentrations...
January 9, 2017: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/28089297/time-since-discharge-of-9mm-cartridges-by-headspace-analysis-part-1-comprehensive-optimisation-and-validation-of-a-headspace-sorptive-extraction-hsse-method
#12
M Gallidabino, F S Romolo, C Weyermann
Estimating the time since discharge of spent cartridges can be a valuable tool in the forensic investigation of firearm-related crimes. To reach this aim, it was previously proposed that the decrease of volatile organic compounds released during discharge is monitored over time using non-destructive headspace extraction techniques. While promising results were obtained for large-calibre cartridges (e.g., shotgun shells), handgun calibres yielded unsatisfying results. In addition to the natural complexity of the specimen itself, these can also be attributed to some selective choices in the methods development...
December 24, 2016: Forensic Science International
https://www.readbyqxmd.com/read/28087213/cholesterolomics-an-update
#13
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/28078517/semivolatile-organic-compounds-in-surface-microlayer-and-subsurface-water-of-dianshan-lake-shanghai-china-implications-for-accumulation-and-interrelationship
#14
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
#15
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/28078400/characterization-of-four-endophytic-fungi-as-potential-consolidated-bioprocessing-hosts-for-conversion-of-lignocellulose-into-advanced-biofuels
#16
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
#17
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
#18
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
#19
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/28073348/wild-carrot-pentane-based-fractions-suppress-proliferation-of-human-hacat-keratinocytes-and-protect-against-chemically-induced-skin-cancer
#20
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
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