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https://www.readbyqxmd.com/read/28098847/polish-yellow-sweet-clover-melilotus-officinalis-l-honey-chromatographic-fingerprints-and-chemical-markers
#1
Izabela Jasicka-Misiak, Ewa Makowicz, Natalia Stanek
A case study of Polish Melilotus officinalis honey was presented for the first time. Gas chromatography-mass spectrometry (GC-MS) (after steam distillation, Soxhlet extraction, ultrasonic solvent extraction, and solid phase extraction (SPE)) and targeted high performance liquid chromatography with a photodiode array detector (HPLC-PAD) were applied to determine the characteristic components of honey. While ubiquitous in most honeys, carbohydrates, terpene derivatives, and phenylacetic acid dominated in the Soxhlet extracts (25...
January 15, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
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
#2
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/28098799/occurrence-of-emerging-micropollutants-in-water-systems-in-gauteng-mpumalanga-and-north-west-provinces-south-africa
#3
Elijah M M Wanda, Hlengilizwe Nyoni, Bhekie B Mamba, Titus A M Msagati
The ubiquitous occurrence of emerging micropollutants (EMPs) in water is an issue of growing environmental-health concern worldwide. However, there remains a paucity of data regarding their levels and occurrence in water. This study determined the occurrence of EMPs namely: carbamazepine (CBZ), galaxolide (HHCB), caffeine (CAF), tonalide (AHTN), 4-nonylphenol (NP), and bisphenol A (BPA) in water from Gauteng, Mpumalanga, and North West provinces, South Africa using comprehensive two-dimensional gas chromatography coupled to high resolution time-of-flight mass spectrometry (GCxGC-HRTOFMS)...
January 13, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28098776/distinguishing-benign-from-malignant-pancreatic-and-periampullary-lesions-using-combined-use-of-%C3%A2-h-nmr-spectroscopy-and-gas-chromatography-mass-spectrometry
#4
Yarrow J McConnell, Farshad Farshidfar, Aalim M Weljie, Karen A Kopciuk, Elijah Dixon, Chad G Ball, Francis R Sutherland, Hans J Vogel, Oliver F Bathe
Previous work demonstrated that serum metabolomics can distinguish pancreatic cancer from benign disease. However, in the clinic, non-pancreatic periampullary cancers are difficult to distinguish from pancreatic cancer. Therefore, to test the clinical utility of this technology, we determined whether any pancreatic and periampullary adenocarcinoma could be distinguished from benign masses and biliary strictures. Sera from 157 patients with malignant and benign pancreatic and periampullary lesions were analyzed using proton nuclear magnetic resonance (¹H-NMR) spectroscopy and gas chromatography-mass spectrometry (GC-MS)...
January 13, 2017: Metabolites
https://www.readbyqxmd.com/read/28097167/expression-purification-and-kinetic-characterization-of-recombinant-benzoate-dioxygenase-from-rhodococcus-ruber-ukmp-5m
#5
Arezoo Tavakoli, Ainon Hamzah, Amir Rabu
In this study, benzoate dioxygenase from Rhodococcus ruber UKMP-5M was catalyzed by oxidating the benzene ring to catechol and other derivatives. The benzoate dioxygenase (benA gene) from Rhodococcus ruber UKMP-5M was then expressed, purified, characterized, The benA gene was amplified (642 bp), and the product was cloned into a pGEM-T vector. The recombinant plasmid pGEMT-benA was digested by double restriction enzymes BamHI and HindIII to construct plasmid pET28b-benA and was then ligated into Escherichia coli BL21 (DE3)...
September 2016: Molecular Biology Research Communications
https://www.readbyqxmd.com/read/28095954/predicting-air-quality-at-first-ingress-into-vehicles-visiting-the-international-space-station
#6
Amelia A Romoser, Robert R Scully, Thomas F Limero, Vanessa De Vera, Patti F Cheng, Jennifer J Hand, John T James, Valerie E Ryder
INTRODUCTION: NASA regularly performs ground-based offgas tests (OGTs), which allow prediction of accumulated volatile pollutant concentrations at first entry on orbit, on whole modules and vehicles scheduled to connect to the International Space Station (ISS). These data guide crew safety operations and allow for estimation of ISS air revitalization systems impact from additional pollutant load. Since volatiles released from vehicle, module, and payload materials can affect crew health and performance, prediction of first ingress air quality is important...
February 1, 2017: Aerospace Medicine and Human Performance
https://www.readbyqxmd.com/read/28095910/profile-of-bioactive-compounds-in-nymphaea-alba-l-leaves-growing-in-egypt-hepatoprotective-antioxidant-and-anti-inflammatory-activity
#7
Riham Omar Bakr, Mona Mohamed El-Naa, Soumaya Saad Zaghloul, Mahmoud Mohamed Omar
BACKGROUND: Nymphaea alba L. represents an interesting field of study. Flowers have antioxidant and hepatoprotective effects, rhizomes constituents showed cytotoxic activity against liver cell carcinoma, while several Nymphaea species have been reported for their hepatoprotective effects. Leaves of N. alba have not been studied before. Therefore, in this study, in-depth characterization of the leaf phytoconstituents as well as its antioxidant and hepatoprotective activities have been performed where N...
January 17, 2017: BMC Complementary and Alternative Medicine
https://www.readbyqxmd.com/read/28095708/locational-comparison-of-essential-oils-from-selected-conifers-of-himachal-pradesh
#8
Shruti Sharma, Vinod Bhatt, Neeraj Kumar, Bikram Singh, Upendra Sharma
Nine samples of essential oil from needles of three conifers of Pinacea family namely Abies pindrow, Picea smithiana and Cedrus deodara collected from three different locations of Himachal Pradesh (India) were evaluated using gas chromatography and gas chromatography-mass spectrometry. A total of 31, 17 and 13 compounds were identified from essential oil of A. pindrow, P. smithiana and C. deodara, respectively. Among the characterised components, monoterpenoid hydrocarbons were predominated. α-Pinene, β-pinene, β-merycene, limonene and camphene were characterised as major components...
January 18, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28095187/fast-extraction-of-polychlorinated-dibenzo-p-dioxin-and-polychlorinated-dibenzofuran-in-sewage-sludge-and-soil-samples
#9
Valéria F Andrade, Alisson F S Durães, Douglas L Cassimiro, Gevany P de Pinho, Flaviano O Silvério
The current environmental legislations recommend monitoring chemical contaminants such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans before the use of sewage sludge on the agricultural land. In this study, a solid-liquid extraction with low-temperature purification (SLE-LTP) was optimized and validated to determine 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran in sewage sludge and soil samples. The analyses were performed by gas chromatography-mass spectrometry operating in the selective ion mode (GC-MS-SIM)...
January 17, 2017: Journal of Environmental Science and Health. Part. B, Pesticides, Food Contaminants, and Agricultural Wastes
https://www.readbyqxmd.com/read/28092163/corrigendum-to-simultaneous-orthogonal-drug-detection-using-fully-integrated-gas-chromatography-with-fourier-transform-infrared-detection-and-mass-spectrometric-detection
#10
(no author information available yet)
No abstract text is available yet for this article.
January 1, 2017: Applied Spectroscopy
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
#11
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/28091886/levels-of-persistent-organic-pollutants-in-breast-milk-of-maya-women-in-yucatan-mexico
#12
Ángel G Polanco Rodríguez, M Inmaculada Riba López, T Angel DelValls Casillas, Jesús Alfredo Araujo León, B Anjan Kumar Prusty, Fernando J Álvarez Cervera
In this study, 24 breast milk samples, obtained from rural Maya women, from municipalities of Yucatan, Mexico, were analyzed for organochlorine pesticide (OCP) residues by gas chromatography. Recent studies have shown that Maya communities have a poor perception about the proper usage and handling of OCP. The karstic soil in this area has a high vulnerability to groundwater pollution by the use of OCP in agriculture and livestock activities. The impact of the ecosystem on human health is much more critical due to the prevailing poverty and a very low educational level of these communities...
February 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/28091587/bacillus-volatiles-adversely-affect-the-physiology-and-ultra-structure-of-ralstonia-solanacearum-and-induce-systemic-resistance-in-tobacco-against-bacterial-wilt
#13
Hafiz Abdul Samad Tahir, Qin Gu, Huijun Wu, Yuedi Niu, Rong Huo, Xuewen Gao
Volatile organic compounds (VOCs) produced by various bacteria have significant potential to enhance plant growth and to control phytopathogens. Six of the most effective antagonistic Bacillus spp. were used in this study against Ralstonia solanacearum (Rsc) TBBS1, the causal agent of bacterial wilt disease in tobacco. Bacillus amyloliquefaciens FZB42 and Bacillus artrophaeus LSSC22 had the strongest inhibitory effect against Rsc. Thirteen VOCs produced by FZB42 and 10 by LSSC22 were identified using gas chromatography-mass spectrometry analysis...
January 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28090975/pesticide-residues-in-leafy-vegetables-and-human-health-risk-assessment-in-north-central-agricultural-areas-of-chile
#14
Sebastian Elgueta, Stella Moyano, Paulina Sepúlveda, Carlos Quiroz, Arturo Correa
To investigate pesticide residue concentrations and potential human health risk, a study was conducted in 118 leafy vegetable samples collected in 2014-2015 from the North Central agricultural areas of Chile. The pesticides residues were determined using the multiresidue QuEChERS method using gas chromatography as well as high-performance liquid chromatography. The results indicated that 27% of the total samples contained pesticide residues above the maximum residue limits of each active ingredient. The maximum estimated daily intake obtained for carbon disulphide (CS2), methamidophos, azoxystrobin and cypermethrin were 0...
January 16, 2017: Food Additives & Contaminants. Part B, Surveillance
https://www.readbyqxmd.com/read/28089931/a-novel-polysaccharide-with-antioxidant-hiv-protease-inhibiting-and-hiv-integrase-inhibiting-activities-from-fomitiporia-punctata-p-karst-murrill-basidiomycota-hymenochaetales
#15
Fang Liu, Yinping Wang, Keren Zhang, Yijun Wang, Rong Zhou, Yan Zeng, Yajie Han, Tzi Bun Ng
A novel polysaccharide fraction (G1) was obtained from the fungus Fomitiporia punctata (P.Karst.) Murrill. G1 exhibited a molecular weight of approximately 151kDa. The FT-IR results suggested that the monosaccharide components of G1 possessed furanoid rings and there were β-glycosidic bonds between the sugar units. The (1)H NMR results showed that G1 was composed of arabinose, fructose, galactose and glucose in the molar ratio of 1.6:3.8:19.7:19.7, as determined by gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC)...
January 12, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28089892/algerian-propolis-extracts-chemical-composition-bactericidal-activity-and-in-vitro-effects-on-gilthead-seabream-innate-immune-responses
#16
El-Khamsa Soltani, Rebeca Cerezuela, Noureddine Charef, Samia Mezaache-Aichour, Maria Angeles Esteban, Mohamed Mihoub Zerroug
Propolis has been used as a medicinal agent for centuries. The chemical composition of four propolis samples collected from four locations of the Sétif region, Algeria, using gas chromatography-mass spectrometry was determined. More than 20 compounds and from 30 to 35 compounds were identified in the aqueous and ethanolic extracts, respectively. Furthermore, the antimicrobial activity of the propolis extracts against two marine pathogenic bacteria was evaluated. Finally, the in vitro effects of propolis on gilthead seabream (Sparus aurata L...
January 9, 2017: Fish & Shellfish Immunology
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
#17
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/28089277/accurate-determination-of-residual-acrylic-acid-in-superabsorbent-polymer-of-hygiene-products-by-headspace-gas-chromatography
#18
Shu-Xin Zhang, Xin-Sheng Chai, Ran Jiang
This work reports on a method for the determination of residual acrylic acid (AA) in the superabsorbent polymers for hygiene products by headspace analysis. It was based on water extraction for the polymer sample at a room temperature for 50min. Then, the AA in the extractant reacted with bicarbonate solution in a closed headspace sample vial, from which the carbon dioxide generated from the reaction (within 20min at 70°C) was detected by gas chromatography (GC). It was found that there is adsorption partition equilibrium of AA between solid-liquid phases...
January 10, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28089274/retention-behavior-of-alkyl-substituted-polycyclic-aromatic-sulfur-heterocycle-isomers-in-gas-chromatography-on-stationary-phases-of-different-selectivity
#19
Walter B Wilson, Lane C Sander, Jorge O Oña-Ruales, Stephanie G Mössner, Leonard M Sidisky, Milton L Lee, Stephen A Wise
Retention indices for 10 sets of alkyl-substituted polycyclic aromatic sulfur heterocycles (PASHs) isomers (total of 80 PASHs) were determined using gas chromatography with three different stationary phases: a 50% phenyl phase, a 50% liquid crystalline dimethylpolysiloxane (LC-DMPS) phase, and an ionic liquid (IL) phase. Correlations between the retention behavior on the three stationary phases and PASH geometry [length-to-breadth (L/B) and thickness (T)] were investigated for the following PASHs: 4 methyl-substituted dibenzothiophenes (DBTs), 3 ethyl-substituted DBTs, 15 dimethyl-substituted DBTs, 8 trimethyl-substituted DBTs, 15 methyl-substituted naphthothiophenes, 30 methyl-substituted benzonaphthothiophenes, and 5 methyl-substituted tetrapheno[1,12-bcd]thiophene...
January 10, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28089272/retention-behavior-of-isomeric-polycyclic-aromatic-sulfur-heterocycles-in-gas-chromatography-on-stationary-phases-of-different-selectivity
#20
Walter B Wilson, Lane C Sander, Jorge O Oña-Ruales, Stephanie G Mössner, Leonard M Sidisky, Milton L Lee, Stephen A Wise
Retention indices for 48 polycyclic aromatic sulfur heterocycles (PASHs) were determined using gas chromatography with three different stationary phases: a 50% phenyl phase, a 50% liquid crystalline dimethylpolysiloxane (LC-DMPS) phase, and an ionic liquid (IL) phase. Correlations between the retention behavior on the three stationary phases and PASH geometry (L/B and T, i.e., length-to-breadth ratio and thickness, respectively) were investigated for the following four isomer sets: (1) 4 three-ring molecular mass (MM) 184Da PASHs, (2) 13 four-ring MM 234Da PASHs, (3) 10 five-ring MM 258Da PASHs, and (4) 20 five-ring MM 284Da PASHs...
January 10, 2017: Journal of Chromatography. A
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