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https://www.readbyqxmd.com/read/28318567/determination-of-ochratoxin-a-in-wine-by-packed-in-tube-solid-phase-microextraction-followed-by-high-performance-liquid-chromatography-coupled-to-tandem-mass-spectrometry
#1
Mariane A Andrade, Fernando M Lanças
Ochratoxin A (OTA), a widely studied mycotoxin, can be found in a variety of food matrices. As its concentration in food is generally low (in the order of μg kg(-1)), sample preparation techniques are necessary for the analyte purification and pre-concentration in order to achieve the required low detection limits. The separation and detection methods used for OTA analysis should also offer proper sensitivity in order to allow the adequate quantification of the analyte. This manuscript addresses the development of a methodology aiming the analysis of OTA in wine samples by packed in-tube SPME in flow through extraction mode coupled to HPLC-MS/MS...
March 1, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28317704/free-and-glycosidically-bound-volatile-compounds-in-sun-dried-raisins-made-from-different-fragrance-intensities-grape-varieties-using-a-validated-hs-spme-with-gc-ms-method
#2
Dong Wang, Chang-Qing Duan, Ying Shi, Bao-Qing Zhu, Hafiz Umer Javed, Jun Wang
The conditions of sample pretreatments and HS-SPME for extracting volatile compounds from raisins were optimized, and the method was validated in the study. Free and glycosidically bound volatile compounds in three different fragrance intensities raisins were analysed using this method. There were 91 compounds identified, and 72, 26 and 8 of these compounds came from fresh grapes, the auto-oxidation of unsaturated fatty acids (UFAO) and the Maillard reaction, respectively. The aroma profiles of Thompson Seedless raisins (TSRs) and Centennial Seedless raisins (CSRs) were similar, while the floral, fruity, green and roasted aromas of CSRs were higher than those of TSRs due to the contributions of benzeneacetaldehyde, 2-pentylfuran, (E)-2-nonenal and 3-ethyl-2,5-dimethyl pyrazine...
August 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28314881/covalent-organic-frameworks-as-a-novel-fiber-coating-for-solid-phase-microextraction-of-volatile-benzene-homologues
#3
Shuaihua Zhang, Qian Yang, Zhi Li, Wenchang Wang, Chun Wang, Zhi Wang
Covalent organic frameworks (COFs) have attracted great research interest due to their fascinating structures and potential applications in various fields. Here, the COF-SCU1 (SCU for Sichuan University) coated solid-phase microextraction (SPME) fibers were fabricated by coating it on prior functionalized stainless steel wires via a simple physical coating method, and applied to extract some volatile benzene homologues from indoor air samples. The main experimental parameters affecting the extraction efficiency were optimized, including extraction temperature, extraction time, and desorption time...
March 18, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28304112/evaluation-of-various-approaches-to-the-isolation-of-steroid-hormones-from-urine-samples-prior-to-fass-mekc-analysis
#4
Ilona Olędzka, Piotr Kowalski, Alina Plenis, Tomasz Bączek
The goal of this study was to assess various analytical approaches for the simultaneous and efficient extraction of steroid hormones (cortisone, cortisol, prednisolone, corticosterone, testosterone, 17α-methyltestosterone, epitestosterone, progesterone) from urine samples prior to separation based on field-amplified sample stacking-micellar electrokinetic chromatography (FASS-MEKC). FASS-MEKC successfully allowed the compounds to be separated within 12 min using a background electrolyte (BGE) comprised of 5 mM sodium tetraborate, 150 mM boric acid, 50 mM SDS and 15% methanol...
March 17, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28298687/composition-of-volatile-aromatic-compounds-and-minerals-of-tarhana-enriched-with-cherry-laurel-laurocerasus-officinalis
#5
Hasan Temiz, Zekai Tarakçı
Different concentrations of cherry laurel pulp (0, 5, 10, 15 and 20%) were used to produce tarhana samples. Volatile aromatic compounds and minor mineral content were investigated. Volatile aromatic compounds were analyzed by using GC-MS with SPME fiber and minor mineral values were evaluated with inductively coupled plasma optical emission spectrometer. The statistical analysis showed that addition of pulp affected volatile aromatic compounds and minor mineral content significantly. Thirty five volatile aromatic compounds were found in tarhana samples...
March 2017: Journal of Food Science and Technology
https://www.readbyqxmd.com/read/28292733/rapid-determination-of-54-pharmaceutical-and-personal-care-products-in-fish-samples-using-microwave-assisted-extraction-hollow-fiber-liquid-solid-phase-microextraction
#6
Yi Zhang, Wen Guo, Zhenfeng Yue, Li Lin, Fengjuan Zhao, Peijin Chen, Weidong Wu, Hong Zhu, Bo Yang, Yanyun Kuang, Jiong Wang
In this paper, a simple, rapid, solvent-less and environmental friendliness microextraction method, microwave-assisted extraction-hollow fiber-liquid/solid phase microextraction (MAE-HF-L/SME), was developed for simultaneous extraction and enrichment of 54 trace hydrophilic/lipophilic pharmaceutical and personal care products (PPCPs) from fish samples. A solid-phase extraction material, solid-phase microextraction (SPME) fiber, was synthesized. The SPME fiber had a homogeneous, loose structure and good mechanical properties, and they exhibited a good adsorption capacity for most PPCPs selected...
January 21, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28292517/a-liquid-chromatography-mass-spectrometry-method-based-on-post-column-derivatization-for-automated-analysis-of-urinary-hexanal-and-heptanal
#7
Di Chen, Jun Ding, Ming-Ke Wu, Tian-Yi Zhang, Chu-Bo Qi, Yu-Qi Feng
A fully automated in-tube solid phase microextraction/liquid chromatography-post column derivatization-mass spectrometry (in-tube SPME/LC-PCD-MS) method was developed for the analysis of urinary hexanal and heptanal. Online in-tube SPME enabled effective enrichment of the low level aldehydes and elimination of matrix interferences. PCD could be simply realized by mixing the LC elute and hydroxylamine hydrochloride (HAHC) solution with just a tee. The peak broadening and loss in separation efficiency associated with post column dead-volume could be ignored and even completely eliminated by employing suitable PCD configuration...
March 1, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28290363/volatile-and-non-volatile-semi-volatile-compounds-and-in-vitro-bioactive-properties-of-chilean-ulmo-eucryphia-cordifolia-cav-honey
#8
Francisca Acevedo, Paulina Torres, B Dave Oomah, Severino Matias de Alencar, Adna Prado Massarioli, Raquel Martín-Venegas, Vicenta Albarral-Ávila, César Burgos-Díaz, Ruth Ferrer, Mónica Rubilar
Ulmo honey originating from Eucryphia cordifolia tree, known locally in the Araucania region as the Ulmo tree is a natural product with valuable nutritional and medicinal qualities. It has been used in the Mapuche culture to treat infections. This study aimed to identify the volatile and non-volatile/semi-volatile compounds of Ulmo honey and elucidate its in vitro biological properties by evaluating its antioxidant, antibacterial, antiproliferative and hemolytic properties and cytotoxicity in Caco-2 cells. Headspace volatiles of Ulmo honey were isolated by solid-phase microextraction (SPME); non-volatiles/semi-volatiles were obtained by removing all saccharides with acidified water and the compounds were identified by GC/MS analysis...
April 2017: Food Research International
https://www.readbyqxmd.com/read/28290321/-1-h-nmr-and-spme-gc-ms-study-of-hydrolysis-oxidation-and-other-reactions-occurring-during-in-vitro-digestion-of-non-oxidized-and-oxidized-sunflower-oil-formation-of-hydroxy-octadecadienoates
#9
Bárbara Nieva-Echevarría, Encarnación Goicoechea, María J Manzanos, María D Guillén
Both fresh and slightly oxidized sunflower oils, as models of omega-6 rich lipids, were submitted to in vitro gastrointestinal digestion and studied by (1)H NMR and SPME-GC/MS. Changes in lipolysis degree, lipid composition and oxidative level were studied by (1)H NMR. Three quantitative approaches were used and several equations were newly developed. In oxidized oil digestates slightly lower hydrolysis and a higher advance of oxidation took place during digestion. This latter was evidenced by a greater decrease of lipid unsaturation degree and enhanced generation of oxidation products (cis,trans-hydroperoxy-octadecadienoates, cis,trans- and trans,trans-hydroxy-octadecadienoates)...
January 2017: Food Research International
https://www.readbyqxmd.com/read/28290313/high-hydrostatic-pressure-treatments-enhance-volatile-components-of-pre-germinated-brown-rice-revealed-by-aromatic-fingerprinting-based-on-hs-spme-gc-ms-and-chemometric-methods
#10
Qiang Xia, Jun Mei, Wenjuan Yu, Yunfei Li
Germination favors to significantly enhance functional components and health attributes of whole-grain brown rice (BR), but the production of germinated BR (GBR) compromises the typical rice flavor perception due to soaking process. Simultaneously, high hydrostatic pressure (HHP) is considered as an effective processing technique to enhance micronutrients utilization efficiency of GBR and improve products flavor, but no information about the effects of HHP treatments on volatile fingerprinting of GBR has been reported...
January 2017: Food Research International
https://www.readbyqxmd.com/read/28287711/rapid-identification-of-unknown-organic-iodine-in-small-volume-complex-biological-samples-based-on-nanospray-mass-spectrometry-coupled-with-in-tube-solid-phase-microextraction
#11
Qing Chang, Yue'e Peng, Lifen Yun, Qingxin Zhu, Shenghong Hu, Qin Shuai
A new method for rapid screening of unknown organic iodine (OI) in small-volume complex biological samples was developed using in-tube solid phase microextraction (SPME) nanospray mass spectrometry (MS). The method proposed a new identification scheme for OI based on nanospray high-resolution mass spectrometry (HR-MS). The mass ranges of OI ions were confirmed using the t-MS2 scan mode firstly; then, the possible precursor ions of OI were selected and identified orderly in full MS/ddMS2 and t-MS2 scan mode...
March 13, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28285522/quantitative-profiling-of-ester-compounds-using-hs-spme-gc-ms-and-chemometrics-for-assessing-volatile-markers-of-the-second-fermentation-in-bottle
#12
José Manuel Muñoz-Redondo, Francisco Julián Cuevas, Juan Manuel León, Pilar Ramírez, Jose-Manuel Moreno Rojas, Maria Jose Ruiz-Moreno
A quantitative approach using HS-SPME-GC-MS was performed to investigate the ester changes related to the second fermentation in bottle. The contribution of the type of base wine to the final wine style is detailed. Furthermore, a discriminant model was developed based on ester changes according to the second fermentation (with 100% sensitivity and specificity values). The application of a double check criteria according to univariate and multivariate analyses allowed the identification of potential volatile markers related to the second fermentation...
March 11, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28284767/fabrication-and-evaluation-of-a-fluorophilic-adsorbent-for-multiple-monolithic-fiber-solid-phase-microextraction-of-fluorobenzenes
#13
Yanmei Huang, Xiaojia Huang
A new type of highly fluorinated monolith (HFM) was fabricated and used as adsorbent of multiple monolithic fiber solid-phase microextraction (MMF-SPME). To prepare the HFM, a fluorinated monomer, 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl acrylate was in situ copolymerized with dual cross-linkers (divinylbenzene and ethylenedimethacrylate). The fabrication parameters including the content of monomer and porogenic solvent in the polymerization mixture were optimized to obtain expected extraction performance and life span...
March 3, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28282901/the-emission-of-the-floral-scent-of-four-osmanthus-fragrans-cultivars-in-response-to-different-temperatures
#14
Jianxin Fu, Dan Hou, Chao Zhang, Zhiyi Bao, Hongbo Zhao, Shaoqing Hu
Floral scent is an important part of volatile organic compounds (VOCs) emitted from plants, and is influenced by many environmental and endogenous factors. To investigate the influence of temperature on the emission of the floral scent of Osmanthus fragrans, the number of chemical compounds and their relative release amounts from four cultivars of O. fragrans under different temperature treatments, were identified using the solid-phase microextraction (SPME) technique and gas chromatography-mass spectrometry (GC-MS) in this study...
March 8, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28278677/fragrance-components-of-platanthera-bifolia-subsp-osca
#15
Maurizio D'Auria, Richard Lorenz, Rocco Racioppi, Vito Antonio Romano
SPME-GC-MS analysis of the scent of Platanthera bifolia subsp. osca collected during the night showed as main components lilac alcohols B, C and D and lilac aldehydes A, B and C. Other significant chemical components were linalool and caryophyllene. Some differences were found in comparison with previously reported analyses of the scent of P. bifolia and Platanthera chlorantha. The most important difference found was in the composition of the ester fraction.
February 10, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28278123/development-and-validation-of-a-spme-gc-method-for-degradation-kinetics-study-of-propiconazole-i-propiconazole-ii-and-tebuconazole-in-blueberries-in-concordia-the-main-production-area-of-argentina
#16
Martín S Munitz, María B Medina, María I T Montti
An analytical method for the simultaneous determination of propiconazole isomers and tebuconazole residues in blueberries was developed, using solid-phase microextraction (SPME) coupled to gas chromatography. Confirmation was performed by gas chromatography-mass spectrometry in selected-ion monitoring mode. The SPME fiber coating selected was CWX-DVB, and the pH was adjusted to 7 with NaOH. The method is selective with adequate precision and high accuracy and sensitivity. Recoveries ranged between 97.4 and 98...
March 2, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28276694/artemisia-umbelliformis-lam-and-g%C3%A3-n%C3%A3-pi-liqueur-volatile-profile-as-a-diagnostic-marker-for-geographic-origin-and-liqueur-safety-prediction
#17
Lorenzo Boggia, Giuseppe Pignata, Barbara Sgorbini, Maria Laura Colombo, Arianna Marengo, Manuela Casale, Silvana Nicola, Carlo Bicchi, Patrizia Rubiolo
A. umbelliformis, commonly known as "white génépi", is characterized by a volatile fraction rich in - and β- thujone, two monoterpenoids; under EU regulations these are limited to 35 mg/L in Artemisia-based beverages , because of their recognized activity on human central nervous system. This study reports the results of an investigation to define the geographical origin and thujone content of individual plants of A. umbelliformis from different geographical sites, cultivated experimentally at a single site, and to predict the thujone content in the resulting liqueurs, through their volatile fraction...
March 9, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28274458/a-study-on-accumulation-of-volatile-organic-compounds-during-ochratoxin-a-biosynthesis-and-characterization-of-the-correlation-in-aspergillus-carbonarius-isolated-from-grape-and-dried-vine-fruit
#18
Xiaoxu Zhang, Zhan Cheng, Liyan Ma, Jingming Li
Volatile organic compounds (VOCs) and ochratoxin A (OTA) were detected in Aspergillus carbonarius strains (AF, SD26 and SD27) during a 7-day growing period, using HS-SPME-GC-MS and HPLC-MS/MS, respectively. Results showed that 33 VOCs were detected in these strains. The AF strain showed the different sesquiterpene profile compared with the other strains. Principal component analysis revealed that the AF strain was segregated from the other two strains regarding the VOC profile, especially the sesquiterpene profile...
July 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28274410/global-volatile-profile-of-virgin-olive-oils-flavoured-by-aromatic-medicinal-plants
#19
R Perestrelo, C Silva, P Silva, J S Câmara
The global volatile profile of commercial virgin olive oils and flavoured olive oils with aromatic/medicinal plants, was established using liquid-liquid microextraction (LLME) and headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-quadrupole mass spectrometry (GC-qMS). More than 60 volatile organic compounds (VOCs belonging to different groups were identified using both methods. Olive oils volatile profile was slightly influenced by maceration process, which occurred at room temperature (20±2°C) for 15days...
July 15, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28273408/profiling-of-compositions-of-essential-oils-and-volatiles-of-salvia-limbata-using-traditional-and-advanced-techniques-and-evaluation-for-biological-activities-of-their-extracts
#20
Majid Mohammadhosseini, Abolfazl Akbarzadeh, Guido Flamini
In the present work, the essential oils and volatiles from flowers, leaves and stems of Salvia limbata obtained using microwave assisted hydrodistillation (MAHD), solvent free microwave extraction (SFME), headspace assisted analysis (HSA) and headspace solid phase microextraction (HS-SPME) have been characterized for the first time. The results have been also compared with those from traditional separation techniques involving hydrodistillation (HD) and steam distillation (SD). Regardless of some common compounds in all of the profiles, some dissimilarities were noted due to the use of different extracting approaches...
March 8, 2017: Chemistry & Biodiversity
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