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https://www.readbyqxmd.com/read/28927018/the-effect-of-harvesting-on-the-composition-of-essential-oils-from-five-varieties-of-ocimum-basilicum-l-cultivated-in-the-island-of-kefalonia-greece
#1
Gerasimia Tsasi, Theofilos Mailis, Artemis Daskalaki, Eleni Sakadani, Panagis Razis, Yiannis Samaras, Helen Skaltsa
Five varieties of Ocimum basilicum L. namely lettuce, cinnamon, minimum, latifolia, and violetto were separately cultivated in field and greenhouse in the island Kefalonia (Greece). The effect of successive harvesting to the essential oil content was evaluated. In total 23 samples of essential oils (EOs) were analyzed by GC-FID and GC-MS. Ninety-six constituents, which accounted for almost 99% of the oils, were identified. Cluster analysis was performed for all of the varieties in greenhouse and field conditions, in order to investigate the possible differentiation on the chemical composition of the essential oils, obtained between harvests during growing period...
September 18, 2017: Plants (Basel, Switzerland)
https://www.readbyqxmd.com/read/28926976/chemical-composition-antibacterial-activity-and-synergistic-effects-with-conventional-antibiotics-and-nitric-oxide-production-inhibitory-activity-of-essential-oil-from-geophila-repens-l-i-m-johnst
#2
Huijuanzi Rao, Pengxiang Lai, Yang Gao
Geophila repens (L.) I.M. Johnst, a perennial herb, belongs to the Rubiaceae family. In this study, we identified the chemical composition of the Geophila repens essential oil (GR-EO) for the first time. Totally, seventy-seven compounds were identified according to GC and GC-MS, which represent 98.0% of the oil. And the major components of GR-EO were β-caryophyllene (23.3%), β-elemene (8.0%), farnesyl butanoate (7.4%), myrcene (3.5%), and trans-nerolidol (3.3%). Then we evaluated the antibacterial activities of GR-EO and the synergistic effects of GR-EO in combination with commercial antibiotics using the microdilution and Checkerboard method...
September 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28926698/quantification-of-lignin-and-its-structural-features-in-plant-biomass-using-13-c-lignin-as-internal-standard-for-pyrolysis-gc-sim-ms
#3
Gijs van Erven, Ries de Visser, Donny W H Merkx, Willem Strolenberg, Peter De Gijsel, Harry Gruppen, Mirjam A Kabel
Understanding mechanisms underlying plant biomass recalcitrance at molecular level can only be achieved by accurate analyses of both content and structural features of the molecules involved. Current quantification of lignin is, however, majorly based on unspecific gravimetric analysis after sulphuric acid hydrolysis. Hence, our research aimed at specific lignin quantification with concurrent characterization of its structural features. Hereto, for the first time, a polymeric (13)C lignin was used as internal standard (IS) for lignin quantification via analytical pyrolysis coupled to gas chromatography with mass-spectrometric detection in selected ion monitoring mode (py-GC-SIM-MS)...
September 19, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28926682/development-of-a-simple-and-valid-method-for-the-trace-determination-of-phthalate-esters-in-human-plasma-using-dispersive-liquid-liquid-microextraction-coupled-with-gc-ms
#4
Karim Ebrahim, Parinaz Poursafa, Mohammad Mehdi Amin
A new method was developed for the trace determination of phthalic acid esters in plasma using dispersive liquid-liquid microextraction and gas chromatography with mass spectrometry analysis. Plasma proteins were efficiently precipitated by trichloroacetic acid and then a mixture of chlorobenzene (as extraction solvent) and acetonitrile (as dispersive solvent) rapidly injected to clear supernatant using a syringe. After the centrifuging, chlorobenzene were sedimented in the bottom of the test tube. 1 μL of this sedimented phase was injected into the gas chromatograph for phthalic acid esters analysis...
September 19, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28926195/non-targeted-volatile-profiles-for-the-classification-of-the-botanical-origin-of-chinese-honey-by-solid-phase-microextraction-and-gc-ms-combined-with-chemometrics
#5
Hui Chen, Linghe Jin, Chunlin Fan, Wenwen Wang
A potential method for the discrimination and prediction of honey samples of various botanical origins was developed based on the non-targeted volatile profiles obtained by solid-phase microextraction with gas chromatography and mass spectrometry combined with chemometrics. The blind analysis of non-targeted volatile profiles was carried out using solid-phase microextraction with gas chromatography and mass spectrometry for 87 authentic honey samples from four botanical origins (acacia, linden, vitex and rape)...
September 19, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28926063/methylglyoxal-attenuates-insulin-signaling-and-downregulates-the-enzymes-involved-in-cholesterol-biosynthesis
#6
Arati B Deshmukh, Shakuntala Bai, Aarthy T, Rubina S Kazi, Reema Banarjee, Rajeshwari Rathore, Vijayakumar Mv, Thulasiram Hv, Manoj Kumar Bhat, Kulkarni Mj
Methylglyoxal (MG) is a highly reactive dicarbonyl known to be elevated under the hyperglycemic conditions of diabetes and is implicated in the development of diabetic complications. Therefore, the current study investigates the role of MG in exacerbating insulin resistance at the insulin signaling level, as well as its effect on the global proteomic level. By using insulin sensitive rat muscle cells (L6) and Chinese hamster ovary (CHO) cells stably expressing the insulin receptor (IR) and a glucose transporter fused with green fluorescent protein (GLUT4-GFP), we have observed that MG impairs insulin signaling, inhibits GLUT4 translocation and reduces glucose uptake...
September 19, 2017: Molecular BioSystems
https://www.readbyqxmd.com/read/28926062/selectivity-of-solid-phase-extraction-for-dissolved-organic-matter-in-the-hypersaline%C3%A2-da-qaidam-lake-china
#7
Keli Yang, Yaoling Zhang, Yaping Dong, Wu Li
Dissolved organic matter (DOM) was isolated from the hypersaline Da Qaidam Lake using solid-phase extraction (SPE) methods with five different adsorbents: ENVI-Carb (non-porous graphitized carbon), HLB, PPL, and XAD-8 (polymer based), and ENVI-18 (silica based). Structure-selective assessments of SPE-DOM isolated using the different adsorbents were conducted using a combination of complementary analysis techniques, including dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) analysis, as well as elemental analysis, Fourier transformed infrared spectroscopy (FTIR), (1)H nuclear magnetic resonance ((1)H NMR) and pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS)...
September 19, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28925102/continued-alcohol-misuse-in-human-cirrhosis-is-associated-with-an-impaired-gut-liver-axis
#8
Jasmohan S Bajaj, Genta Kakiyama, Derrick Zhao, Hajime Takei, Andrew Fagan, Phillip Hylemon, Huiping Zhou, William M Pandak, Hiroshi Nittono, Oliver Fiehn, Nita Salzman, Mary Holtz, Pippa Simpson, Edith A Gavis, Douglas M Heuman, Runping Liu, Dae Joong Kang, Masoumeh Sikaroodi, Patrick M Gillevet
BACKGROUND: Cirrhosis and alcohol can independently affect the gut-liver axis with systemic inflammation. However their concurrent impact in humans is unclear. AIM: Determine the effect of continued alcohol misuse on the gut-liver axis in cirrhotic patients. METHODS: Age and MELD-balanced cirrhotic patients who were currently drinking (Alc) or abstinent (NAlc), and healthy controls underwent serum and stool collection. A subset underwent upper endoscopy and colonoscopy for biopsies and duodenal fluid collection...
September 19, 2017: Alcoholism, Clinical and Experimental Research
https://www.readbyqxmd.com/read/28924453/a-novel-and-efficient-fungal-delignification-strategy-based-on-versatile-peroxidase-for-lignocellulose-bioconversion
#9
Wen Kong, Xiao Fu, Lei Wang, Ahmad Alhujaily, Jingli Zhang, Fuying Ma, Xiaoyu Zhang, Hongbo Yu
BACKGROUND: The selective lignin-degrading white-rot fungi are regarded to be the best lignin degraders and have been widely used for reducing the saccharification recalcitrance of lignocellulose. However, the biological delignification and conversion of lignocellulose in biorefinery is still limited. It is necessary to develop novel and more efficient bio-delignification systems. RESULTS: Physisporinus vitreus relies on a new versatile peroxidase (VP)-based delignification strategy to remove enzymatic recalcitrance of corn stover efficiently, so that saccharification of corn stover was significantly enhanced to 349...
2017: Biotechnology for Biofuels
https://www.readbyqxmd.com/read/28923727/role-of-induced-glutathione-s-transferase-from-helicoverpa-armigera-lepidoptera-noctuidae-hagst-8-in-detoxification-of-pesticides
#10
Chaitali P Labade, Abhilash R Jadhav, Mehul Ahire, Smita S Zinjarde, Vaijayanti A Tamhane
The present study deals with glutathione-S-transferase (GST) based detoxification of pesticides in Helicoverpa armigera and its potential application in eliminating pesticides from the environment. Dietary exposure of a pesticide mixture (organophosphates - chlorpyrifos and dichlorvos, pyrethroid - cypermethrin; 2-15ppm each) to H. armigera larvae resulted in a dose dependant up-regulation of GST activity and gene expression. A variant GST from H. armigera (HaGST-8) was isolated from larvae fed with 10ppm pesticide mixture and it was recombinantly expressed in yeast (Pichia pastoris HaGST-8)...
September 15, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28923567/a-water-soluble-polysaccharide-from-the-roots-of-polygala-tenuifolia-suppresses-ovarian-tumor-growth-and-angiogenesis-in-vivo
#11
Hua Yao, Ping Cui, Dan Xu, Yunduo Liu, Qinghua Tian, Fubin Zhang
PTP, one polysaccharide extracted from the roots of Polygala tenuifolia, has displayed anti-cancer activity in several types of ovarian cancer cells. This study aims to elucidate the structure of PTP and investigate its anticancer effects against SKOV3 xenograft tumor growth in BALB/c mice, as well as the underlying mechanisms involved. GC-MS and NMR data indicate that PTP has a backbone composed of 1,4,6-linked-β-Galp, 1,4-linked-β-Galp and 1,4-linked-β-Glcp, with non-reducing terminal 1-linked-α-Glcp attached to O-6 of 1,4,6-linked-β-Galp...
September 15, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28922759/transcriptomic-and-metabolomics-responses-to-elevated-cell-wall-invertase-activity-during-tomato-fruit-set
#12
Lei Ru, Sonia Osorio, Lu Wang, Alisdair R Fernie, John W Patrick, Yong-Ling Ruan
Fruit set is a developmental transition from ovaries to fruitlets that determines yield potential. Cell wall invertase (CWIN) is essential for fruit and seed set, but the underlying molecular basis remains elusive. We addressed this issue by using CWIN-elevated transgenic tomato, focusing on ovaries and fruitlets at 2 d before and after anthesis, respectively. RNAseq analyses revealed that ovaries and fruitlets exhibited remarkable differences in their transcriptomic responses to elevated CWIN activity. Ovaries 2 d before anthesis were far more responsive to elevated CWIN activity compared with the fruitlets...
July 10, 2017: Journal of Experimental Botany
https://www.readbyqxmd.com/read/28922660/mitochondrial-dysfunction-and-altered-renal-metabolism-in-dahl-salt-sensitive-rats
#13
Zhengjun Wang, Qiong Sun, Na Sun, Mingyu Liang, Zhongmin Tian
BACKGROUND/AIMS: The kidney plays a critical role in the control of blood pressure and its elevation in salt-induced hypertension. Mitochondrial dysfunction, especially in energy metabolism, has been associated with hypertension. Here, we aimed to investigate mitochondrial function and metabolic features in renal mitochondria of Dahl salt-sensitive (SS) rats to gain further insight into the relationship between mitochondrial metabolism and predisposition to hypertension. METHODS: In this study, SS rats fed low-salt (LS) or high-salt (HS) diets were used to investigate mitochondrial function and metabolism including mitochondrial enzyme activities, pyridine nucleotides, metabolites, and oxidative stress by biochemical analysis and gas chromatography-mass spectrometer (GC-MS)...
September 19, 2017: Kidney & Blood Pressure Research
https://www.readbyqxmd.com/read/28919754/preparation-of-coffee-oil-algae-oil-based-nanoemulsions-and-the-study-of-their-inhibition-effect-on-uva-induced-skin-damage-in-mice-and-melanoma-cell-growth
#14
Chu-Ching Yang, Chi-Feng Hung, Bing-Huei Chen
Coffee grounds, a waste by-product generated after making coffee, contains approximately 15% coffee oil which can be used as a raw material in cosmetics. Algae oil rich in docosahexaenoic acid (DHA) has been demonstrated to possess anticancer and anti-inflammation functions. The objectives of this study were to develop a gas chromatography-mass spectrometry (GC-MS) method for the determination of fatty acids in coffee oil and algae oil and prepare a nanoemulsion for studying its inhibition effect on ultraviolet A-induced skin damage in mice and growth of melanoma cells B16-F10...
2017: International Journal of Nanomedicine
https://www.readbyqxmd.com/read/28918279/seasonal-variation-of-chloro-s-triazines-in-the-hartbeespoort-dam-catchment-south-africa
#15
Cornelius Rimayi, David Odusanya, Jana M Weiss, Jacob de Boer, Luke Chimuka
Seasonal variation of eight chloro-s-triazine herbicides and seven major atrazine and terbuthylazine degradation products was monitored in the Hartbeespoort Dam catchment using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS/MS). Lake, river and groundwater were sampled from the Hartbeespoort Dam catchment over four seasons and the downstream Jukskei River was monitored during the winter season. Triazine herbicide concentrations in the Hartbeespoort Dam were in the order atrazine>simazine>propazine>ametryn>prometryn throughout the four seasons sampled...
September 14, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28917968/the-effect-of-fennel-essential-oil-in-combination-with-antibiotics-on-staphylococcus-aureus-strains-isolated-from-carriers
#16
Paweł Kwiatkowski, Magdalena Mnichowska-Polanowska, Agata Pruss, Helena Masiuk, Małgorzata Dzięcioł, Stefania Giedrys-Kalemba, Monika Sienkiewicz
An increase in the number of staphylococcal infections and carriers among medical staff has forced us to seek more and more effective antibacterial agents. Bacteria from the Staphylococcus genus possessing different mechanisms of resistance are the cause of nosocomial infections. The objective of our investigations was susceptibility of S. aureus strains isolated from nasal vestibule of medical students to fennel essential oil. The GC-MS analysis of fennel essential oil revealed eleven constituents among which a majority of trans-anethole (80%) was found...
September 13, 2017: Burns: Journal of the International Society for Burn Injuries
https://www.readbyqxmd.com/read/28917930/structural-characterization-and-rheological-behavior-of-a-heteroxylan-extracted-from-plantago-notata-lagasca-plantaginaceae-seeds
#17
Fatima Benaoun, Cédric Delattre, Zakaria Boual, Alina V Ursu, Christophe Vial, Christine Gardarin, Anne Wadouachi, Didier Le Cerf, Tony Varacavoudin, Mohamed Didi Ould El-Hadj, Philippe Michaud, Guillaume Pierre
Plantago notata (Plantaginaceae) is a spontaneous plant from Septentrional Algerian Sahara currently used by traditional healers to treat stomach disorders, inflammations or wound healing. A water-soluble polysaccharide, called PSPN (PolySaccharide fraction from Plantago Notata), was extracted and purified from the seeds of this semi-arid plant. The structural features of this mucilage were evaluated by colorimetric assays, Fourier transformed infrared spectroscopy (FT-IR), gas chromatography coupled to mass spectrometry (GC/MS) and (1)H/(13)C Nuclear Magnetic Resonance (NMR) spectroscopy...
November 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28917908/structural-elucidation-of-the-main-water-soluble-polysaccharide-from-rubus-anatolicus-roots
#18
Neda Sahragard, Kambiz Jahanbin
An acidic heteropolysaccharide, RAPS-1, was isolated from the roots of Rubus anatolicus by water extraction (70°C) and purification using DEAE-cellulose A52 and Sephadex G-100 column chromatography. The total sugar content and specific optical rotation of RAPS-1 were 96.3% and +196°, respectively. RAPS-1 had a molecular weight of 7900Da, and was composed of glucose, galactose, and glucuronic acid with a relative molar ratio of 6.2: 1.0: 1.2. Structural features of RAPS-1 were elucidated by a combination of partial acid hydrolysis, periodate oxidation and Smith degradation, methylation, GC-MS, FTIR, and NMR ((13)C and (1)H) analysis...
November 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28917881/structural-characterization-and-rheological-properties-of-a-galactomannan-from-astragalus-gombo-bunge-seeds-harvested-in-algerian-sahara
#19
T Chouana, G Pierre, C Vial, C Gardarin, A Wadouachi, D Cailleu, D Le Cerf, Z Boual, M D Ould El Hadj, P Michaud, C Delattre
A water soluble polysaccharide (WSP) was extracted and purified from Astragalus gombo seeds (Fabaceae) harvested in Septentrional Sahara (Ouargla, Algeria) with a yield of 6.8% (w/w of the dry seed ground). It was characterized by gas chromatography coupled to the mass spectrometry (GC-MS), size exclusion chromatography with Multi-Angle Light Scattering analysis (SEC-MALLS), high-resolution (1)H and (13)C NMR, and rheological measurements. The structural characterization indicated that this WSP fraction is a galactomannan with a mannose/galactose ratio of 1...
November 1, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28917789/chemometric-optimization-of-the-extraction-and-derivatization-of-parabens-for-their-determination-in-water-samples-by-rotating-disk-sorptive-extraction-and-gas-chromatography-mass-spectrometry
#20
Mercedes Becerra-Herrera, Valentina Miranda, Daniel Arismendi, Pablo Richter
A combination of rotating disk sorptive extraction (RDSE) using Oasis® HLB as the sorbent phase and gas chromatography mass spectrometry (GC-MS) has been performed for the determination of four of the most widely used parabens: methylparaben, ethylparaben, propylparaben and n-butylparaben. The extraction and derivatization of the analytes in water samples were optimized by using factorial (screening) and Doehlert designs, thus reducing the number of analyses with the concomitant reduction of time, reagents, waste, samples and cost...
January 1, 2018: Talanta
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