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Maria Elisabete Machado
The present review reports, for the first time, various comprehensive two-dimensional gas chromatography (GC×GC) applications for different fossil fuel matrices (crude oil, heavy gas oil (HGO), light and middle distillates, coal and shale oil) for the determination of nitrogen-containing compounds. The focus is on the various types of detectors (universal and specific), and their applicability for the separation and speciation of nitrogen compounds (N-compounds) was evaluated. The capability of GC×GC to provide additional chemically specific information using different detector types, including a flame ionization detector (FID), a nitrogen chemiluminescence detector (NCD), a nitrogen-phosphorus (NPD) detector and detectors in combination with mass spectrometry (MS), is described...
June 1, 2019: Talanta
Ivano Vigliante, Giuseppe Mannino, Massimo E Maffei
BACKGROUND: Griffonia simplicifolia Baill. (Caesalpiniaceae) is a medicinal plant whose seeds are widely used in traditional medicine for their high content of 5-hydroxy-l-tryptophan (5-HTP), a direct precursor and enhancer of the activity of the brain hormone serotonin (5-HT). The plant extracts are used in dietary supplements aimed to alleviate serotonin-related disorders. METHODS: In order to characterize the chemical components of G. simplicifolia seeds and their identity, we used a combined methodology by using HPLC-DAD-ESI-MS/MS for the qualitative and quantitative determination of the N -containing compounds, GC-FID and GC-MS for the characterization of the major fatty acids, and DNA fingerprinting based on PCR⁻RFLP for the unequivocal identification of the plant...
March 15, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Ibrahim Aissa, Vijaykumar D Nimbarte, Afifa Zardi-Bergaoui, Mansour Znati, Guido Flamini, Roberta Ascrizzi, Hichem Ben Jannet
The chemical composition of the essential oil (LEO) and its volatile fractions (V1 -V10 ) collected during the hydrodistillation process every 15 min from the fresh leaves of I. viscosa (L.), growing in Tunisia, were analyzed by GC-FID and GC/MS. Eighty-two compounds, representing 90.9-99.4 % of the total samples, were identified. The crude essential oil (LEO) and its fractions (V1 -V10 ) were characterized by the presence of a high amount of oxygenated sesquiterpenes (82.7-95.8 %). Isocostic acid (1) was found to be the most abundant component (37...
March 15, 2019: Chemistry & Biodiversity
Mansour Miran, Mohammad Mehdi Feizabadi, Hossein Kazemian, Jalil Kardan-Yamchi, Hamid Reza Monsef-Esfahani, Samad Nejad Ebrahimi
Background and Objectives: Essential oils are used for controlling and preventing human diseases and the application of those can often be quite safe and effective with no side effect. The essential oils have been found to have antiparasitic, antifungal, antiviral, antioxidant and especially antibacterial activity including antibacterial activity against tuberculosis. In this study the chemical composition and anti-TB activity of essential oil extracted from Levisticum officinale has been evaluated...
December 2018: Iranian Journal of Microbiology
Leonid Grunin, Mecit Halil Oztop, Selen Guner, Saadet Fatma Baltaci
Time domain NMR (TD-NMR) techniques are frequently used in polymer, pharmaceutical and food industries as they offer rapid experimentation and generally do not require any considerable preliminary sample preparation. Detection of solid and liquid fractions in a sample is possible with the Free Induction Decay (FID). However, for the classical FID sequence that consists of a single pulse followed by relaxation decay acquisition, the dead time of the probe (ring-out of resonance circuitry) occurs and varies between 5-15 μs for standard 10 mm tubes...
March 14, 2019: Magnetic Resonance in Chemistry: MRC
Kobra Zavar Mousavi, Yadollah Yamini, Babak Karimi, Shahram Seidi, Mojtaba Khorasani, Mostafa Ghaemmaghami, Hojatollah Vali
The authors describe the preparation of two kinds of periodic mesoporous organosilicas (PMOs). The first kind is monofunctional and has a bridged alkyl imidazolium framework (PMO-IL). The other is a two-dimensional (2D) hexagonal bifunctional periodic mesoporous organosilica (BFPMO) with bridged IL-phenyl or -ethyl units. The CPMOs were utilized as highly sensitive and stable sorbents for microextraction by packed sorbent. The materials were characterized by SEM, TEM, FT-IR, and N2 adsorption-desorption analysis...
March 13, 2019: Mikrochimica Acta
Keiko Hirakawa, Kaoru Koike, Yoshimasa Kanawaku, Tsuyoshi Moriyama, Norio Sato, Takao Suzuki, Kenichi Furihata, Youkichi Ohno
Proton nuclear magnetic resonance (NMR) is useful for the analysis of biological samples such as serum. Free induction decays (FIDs) are NMR signals that follow a radio-frequency pulse applied at the resonance frequency. Short-time Fourier transform (STFT) is a basic method for time-frequency analyses. The purpose of this study was to ascertain whether the STFT of FIDs enables the sensitive detection of changes and differences in serum properties. FIDs were obtained from serum collected from young, healthy, male volunteers ≤ 40 years of age and seniors ≥ 65 years of age...
March 13, 2019: Journal of Oleo Science
Alina Chernova, Pavel Mazin, Svetlana Goryunova, Denis Goryunov, Yakov Demurin, Lyudmila Gorlova, Anna Vanyushkina, Waltraud Mair, Nikolai Anikanov, Ekaterina Yushina, Anna Pavlova, Elena Martynova, Sergei Garkusha, Zhanna Mukhina, Elena Savenko, Philipp Khaitovich
Oilseed crops are one of the most important sources of vegetable oils for food and industry. Nutritional and technical properties of vegetable oil are primarily determined by its fatty acid (FA) composition. The content and composition of FAs in plants are commonly determined using gas chromatography-mass spectrometry (GS-MS) or gas chromatography-flame ionization detection (GC-FID) techniques. In the present work, we applied ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) technique to FA profiling of sunflower and rapeseed seeds and compared this method with the GC-FID technique...
2019: PeerJ
Christian Becker, Maik A Jochmann, Torsten C Schmidt
In the past, the main focus of flame ionization detector (FID) response studies was set on investigations of gas chromatography (GC) relevant analytes such as aliphatic hydrocarbons and selected functional groups. Only a few data are available for liquid chromatography (LC)/FID responses. Within this research paper, we present the FID response factors for a LC/FID system with an aqueous eluent as mobile phase. The study focus on the most common analytes of LC/FID studies in the past as well as several compounds that are not directly GC compatible because of their polarity...
March 12, 2019: Analytical and Bioanalytical Chemistry
Maryam Sayah, Vahid Kiarostami
A fast, green and low cost method for analysis of acrylamide in tap and well water has been presented for the first time using solvent terminated-dispersive liquid liquid microextraction (ST-DLLME) with a simple equipment which does not need centrifugation step followed by GC-FID. The use of one variable at a time optimization method revealed that methanol and octanone were the superior disperser and extraction solvents, respectively. A central composite design (CCD) as a response surface methodology was used for multivariate optimization of five independent factors (volumes of extraction and dispersive solvents, pH, salt addition and extraction time) on the extraction efficiency...
March 11, 2019: Bulletin of Environmental Contamination and Toxicology
Jatinder Kumar, Shahanshah Khan, S K Mandotra, Priyanka Dhar, Amol B Tayade, Sheetal Verma, Kiran Toppo, Rajesh Arora, Dalip K Upreti, Om P Chaurasia
The high altitude trans-Himalayan region indeed is hostile domain for survival. Algae inhabiting  this  hostile terrain have evolutionarily developed mechanisms to produce unique adaptogenic molecules against climatic stressors. The present study has focused on the high altitude alga Spirogyra porticalis (Muell.) Cleve- a filamentous Charophyte, and reports the estimation of amino acids (AAs), fatty acids (FAs), vitamins and their efficacy against oxidative stress. Reverse phase-HPLC, GC-FID and rapid resolution-LC/tandem mass spectrometry were used for analysis of AAs, FAs and vitamins...
March 11, 2019: Scientific Reports
Asma El Ayeb-Zakhama, Hassiba Chahdoura, Borhane Eddine Cherif Ziani, Mejdi Snoussi, Mehdi Khemiss, Guido Flamini, Fethia Harzallah-Skhiri
This study aimed to identify the physicochemical and the chemical properties of Ailanthus altissima (Miller) Swingle seed oil and to evaluate its in vitro antioxidant and antibacterial activities and in vivo analgesic and anti-inflammatory activities. The fatty acids' composition was determined using GC-FID. The oil was screened for antioxidant activity by DPPH test. The analgesic and anti-inflammatory activities were determined using the acetic acid writhing test in mice and the carrageenan-induced paw edema assay in rats, respectively...
March 11, 2019: Environmental Science and Pollution Research International
S Santisi, M Catalfamo, M Bonsignore, G Gentile, E Di Salvo, M Genovese, M Mahjoubi, A Cherif, G Mancini, M Hassanshahian, G Pioggia, S Cappello
AIMS: The aims of this study were: i) the characterization of the structure of the indigenous microbial community associated with the sediments under study; ii) the isolation and characterization of microbial consortia able to degrade the aged hydrocarbons contaminating the sediments and iii) the assessment of related biodegradation capability of selected consortia. METHODS AND RESULTS: Samples of surface sediments were collected in Priolo Gargallo Harbor (Sicily, Italy)...
March 8, 2019: Journal of Applied Microbiology
Igor Jerković, Marina Kranjac, Zvonimir Marijanović, Bojan Šarkanj, Ana-Marija Cikoš, Krunoslav Aladić, Sandra Pedisić, Stela Jokić
The focus of present study is on Codium bursa collected from the Adriatic Sea. C. bursa volatiles were identified by gas chromatography and mass spectrometry (GC-FID; GC-MS) after headspace solid-phase microextraction (HS-SPME), hydrodistillation (HD), and supercritical CO₂ extraction (SC-CO₂). The headspace composition of dried (HS-D) and fresh (HS-F) C. bursa was remarkably different. Dimethyl sulfide, the major HS-F compound was present in HS-D only as a minor constituent and heptadecane percentage was raised in HS-D...
February 27, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Conall R Strain, Kenneth C Collins, Violetta Naughton, Emeir M McSorley, Catherine Stanton, Thomas J Smyth, Anna Soler-Vila, Mary C Rea, Paul R Ross, Paul Cherry, Philip J Allsopp
BACKGROUND: Brown seaweeds are known to be a rich source of fiber with the presence of several non-digestible polysaccharides including laminarin, fucoidan and alginate. These individual polysaccharides have previously been shown to favorably alter the gut microbiota composition and activity albeit the effect of the collective brown seaweed fiber component on the microbiota remains to be determined. METHODS: This study investigated the effect of a crude polysaccharide-rich extract obtained from Laminaria digitata (CE) and a depolymerized CE extract (DE) on the gut microbiota composition and metabolism using an in vitro fecal batch culture model though metagenomic compositional analysis using 16S rRNA FLX amplicon pyrosequencing and short-chain fatty acid (SCFA) analysis using GC-FID...
February 25, 2019: European Journal of Nutrition
Rosanna Tarkany Basting, Humberto Moreira Spindola, Ilza Maria de Oliveira Sousa, Nubia de Cassia Almeida Queiroz, José Roberto Trigo, João Ernesto de Carvalho, Mary Ann Foglio
This study evaluated the pharmacological effect of the association of crude extract from the fruits of Pterodon pubescens (Pp) with the essential oil of Cordia verbenacea (Cv) in antinociception and anti-inflammatory experimental models. The effective doses of each extract and the combinations used in the associations of extracts were defined by acetic acid-induced writhing test. The separate extracts were also evaluated on formalin test. Interaction between extracts was assessed by isobologram method. The effects of different concentrations of associations (A50, A100 and A200 ) were evaluated on formalin test, tail flick and hot plate...
February 20, 2019: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
Songul Karakaya, Mehmet Koca, Serdar Volkan Yılmaz, Kadir Yıldırım, Nur Münevver Pınar, Betül Demirci, Marian Brestic, Oksana Sytar
Coumarins and essential oils are the major components of the Apiaceae family and the Zosima genus. The present study reports anticholinesterase and antioxidant activities of extracts and essential oils from aerial parts, roots, flowers, fruits and coumarins-bergapten ( 1 ); imperatorin ( 2 ), pimpinellin ( 3 ) and umbelliferone ( 4 )-isolated of the roots from Zosima absinthifolia . The investigation by light and scanning electron microscopy of the structures of secretory canals found different chemical compositions in the various types of secretory canals which present in the aerial parts, fruits and flowers...
February 17, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Ramesh Kumar Chowdari, Shilpa Agarwal, Hero Jan Heeres
The conversion of lignin to biofuels and biobased chemicals is currently attracting a lot of attention. We here report on the valorization of Kraft lignin by a catalytic hydrotreatment using Ni, Mo, and W phosphide catalysts supported on activated carbon in the absence of an external solvent. Experiments were carried out in a batch setup in the temperature range of 400-500 °C and 100 bar initial H2 pressure. The synthesized catalysts were characterized by X-ray diffraction, nitrogen physisorption, and transmission electron microscopy...
January 22, 2019: ACS Sustainable Chemistry & Engineering
Chenxing Zhao, Baocai Li, Dan Liu, Weifeng Dai, Lang Cao, Mi Zhang
Cananga odorata (Lamk.) Hook. f. et Thoms., belonging to Annonaceae, is an evergreen tree. The oils extracted from its flower are a famous perfume and used in daily chemical and food industry. Although this plant has been widely cultivated in tropical regions of the world, the yield of oils from its flower is very limited. In order to develop the other parts of this plant, the chemical constituents of the volatile oils from the leaves of C. odorata was analyzed by gas chromatography/flame ionization detector (GC-FID) and GC/mass spectrometry (GC-MS)...
January 2019: Pakistan Journal of Pharmaceutical Sciences
Barbara Sgorbini, Cecilia Cagliero, Stefano Acquadro, Arianna Marengo, Chiara Cordero, Erica Liberto, Carlo Bicchi, Patrizia Rubiolo
A correct botanical identification and analytical quality control of volatile key-markers responsible for aroma and biological activities is necessary to monitor volatile compounds transferred from a plant to the related herbal tea and human intake to guarantee their safe use. This is mainly true for markers limited by regulations or by a recommended maximum amount of consumption per day. GC-MS is the elective technique to analyze volatiles, provided that for aqueous samples (herbal teas) an appropriate sample preparation procedure, and/or a water-compatible GC stationary phases are applied...
February 6, 2019: Journal of Chromatography. A
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