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https://www.readbyqxmd.com/read/28938786/prediction-of-egg-freshness-during-storage-using-electronic-nose
#1
Samuel M Yimenu, J Y Kim, B S Kim
The aim of the present study was to investigate the potential of a fast gas chromatography (GC) e-nose for freshness discrimination and for prediction of storage time as well as sensory and internal quality changes during storage of hen eggs. All samples were obtained from the same egg production farm and stored at 20 °C for 20 d. Egg sampling was conducted every 0, 3, 6, 9, 12, 16, and 20 d. During each sampling time, 4 egg cartons (each containing 10 eggs) were randomly selected: one carton for Haugh units, one carton for sensory evaluation and 2 cartons for the e-nose experiment...
October 1, 2017: Poultry Science
https://www.readbyqxmd.com/read/28938494/supercritical-fluid-chromatography-in-natural-product-analysis-an-update
#2
Nora Gibitz Eisath, Sonja Sturm, Hermann Stuppner
The wide chemical diversity of natural products has challenged analysts all over the world and has been a driving force for the development of innovative technologies since decades. In the last years, supercritical fluid chromatography (SFC) has finally emerged from the shadow of liquid chromatography (LC) and gas chromatography (GC) and has become a powerful tool in modern natural product analysis. Whereas in the past the technique had mainly been restricted to a small group of nonpolar compounds, it has largely expanded its suitability in the last years and has demonstrated possibilities without boundaries...
September 22, 2017: Planta Medica
https://www.readbyqxmd.com/read/28937988/differential-effects-of-rice-bran-cultivars-to-limit-salmonella-typhimurium-in-chicken-cecal-in-vitro-incubations-and-impact-on-the-cecal-microbiome-and-metabolome
#3
Peter M Rubinelli, Sun Ae Kim, Si Hong Park, Stephanie M Roto, Nora Jean Nealon, Elizabeth P Ryan, Steven C Ricke
In this study, rice brans from different cultivars (Calrose, Jasmine, and Red Wells) were assessed for their ability to inhibit Salmonella enterica serovar Typhimurium using an in vitro mixed anaerobic culture system containing cecal microbiota obtained from broilers of different ages. Salmonella Typhimurium was added to controls (feed only, cecal only, and feed + cecal material) and treatments (feed + cecal + different rice brans) and S. Typhimurium populations were enumerated at 0, 24, and 48 h. Two experimental conditions were applied 1) unadapted condition in which S...
2017: PloS One
https://www.readbyqxmd.com/read/28937864/determination-of-seven-pyrethroid-pesticides-residue-in-vegetables-by-gas-chromatography-using-carboxylated-multi-walled-carbon-nanotubes-as-dispersion-solid-phase-extraction-sorbent
#4
Peng Sun, Yuling Gao, Chong Xu, Yongfu Lian
:A novel carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) dispersive solid phase extraction (d-SPE) method combined with gas chromatography (GC) with ECD detection was developed for the determination of seven pyrethroid pesticides in cucumber, spinach, eggplant, tomato and carrot. We optimized d-SPE conditions including the type and volume of the extractant, the type and amount of the sorbent, and shaking time. Under the optimal conditions, the linear range was from 2.0 to 2000 μg kg(-1). The recoveries were from 88...
September 22, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28937796/delay-of-lung-adenocarcinoma-lac-1-development-in-mice-by-dietary-oleic-acid
#5
Mariana Piegari, Elio A Soria, Aldo R Eynard, Mirta A Valentich
Lung cancer is the leading cause of death by cancer, and is a major sanitary concern worldwide. Some nutrients, such as ω-9 fatty acids, have been proposed as anticancer agents. Thus, an olein-enriched diet was assayed in a murine model of lung adenocarcinoma (LAC-1) to evaluate neoplastic and paraneoplastic evolution in BALB/c mice. The organic assimilation of dietary fatty acids was confirmed in liver by gas chromatography. This experimental oleic acid-containing diet increased animal survival and tumour latency (analysed by the Kaplan-Meier method), improving neoplastic evolution and general status, with weak effects on the paraneoplastic syndrome (thymus atrophy, splenomegaly, splenocyte response to mitogen, blood anaemia, and leucocytosis)...
September 22, 2017: Nutrition and Cancer
https://www.readbyqxmd.com/read/28936796/biosurfactants-produced-by-bacillus-subtilis-a1-and-pseudomonas-stutzeri-na3-reduce-longevity-and-fecundity-of-anopheles-stephensi-and-show-high-toxicity-against-young-instars
#6
Punniyakotti Parthipan, Raja Kumaresan Sarankumar, Anitha Jaganathan, Pandian Amuthavalli, Ranganathan Babujanarthanam, Pattanathu K S M Rahman, Kadarkarai Murugan, Akon Higuchi, Giovanni Benelli, Aruliah Rajasekar
Anopheles stephensi acts as vector of Plasmodium parasites, which are responsible for malaria in tropical and subtropical areas worldwide. Currently, malaria management is a big challenge due to the presence of insecticide-resistant strains as well as to the development of Plasmodium species highly resistant to major antimalarial drugs. Therefore, the present study focused on biosurfactant produced by two bacteria Bacillus subtilis A1 and Pseudomonas stutzeri NA3, evaluating them for insecticidal applications against malaria mosquitoes...
September 21, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28934165/salmonella-o48-serum-resistance-is-connected-with-the-elongation-of-the-lipopolysaccharide-o-antigen-containing-sialic-acid
#7
Aleksandra Pawlak, Jacek Rybka, Bartłomiej Dudek, Eva Krzyżewska, Wojciech Rybka, Anna Kędziora, Elżbieta Klausa, Gabriela Bugla-Płoskońska
Complement is one of the most important parts of the innate immune system. Some bacteria can gain resistance against the bactericidal action of complement by decorating their outer cell surface with lipopolysaccharides (LPSs) containing a very long O-antigen or with specific outer membrane proteins. Additionally, the presence of sialic acid in the LPS molecules can provide a level of protection for bacteria, likening them to human cells, a phenomenon known as molecular mimicry. Salmonella O48, which contains sialic acid in the O-antigen, is the major cause of reptile-associated salmonellosis, a worldwide public health problem...
September 21, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28934162/gas-chromatography-mass-spectrometry-for-metabolite-profiling-of-japanese-black-cattle-naturally-contaminated-with-zearalenone-and-sterigmatocystin
#8
Katsuki Toda, Emiko Kokushi, Seiichi Uno, Ayaka Shiiba, Hiroshi Hasunuma, Yasuo Fushimi, Missaka P B Wijayagunawardane, Chunhua Zhang, Osamu Yamato, Masayasu Taniguchi, Johanna Fink-Gremmels, Mitsuhiro Takagi
The objective of this study was to evaluate the metabolic profile of cattle fed with or without zearalenone (ZEN) and sterigmatocystin (STC)-contaminated diets using a gas chromatography-mass spectrometry metabolomics approach. Urinary samples were collected from individual animals (n = 6 per herd) from fattening female Japanese Black (JB) cattle herds (23 months old, 550-600 kg). Herd 1 had persistently high urinary ZEN and STC concentrations due to the presence of contaminated rice straw. Herd 2, the second female JB fattening herd (23 months old, 550-600 kg), received the same dietary feed as Herd 1, with non-contaminated rice straw...
September 21, 2017: Toxins
https://www.readbyqxmd.com/read/28934005/risk-assessment-of-dietary-exposure-to-phytosterol-oxidation-products-from-baked-food-in-china
#9
Yinzhou Hu, Mengmeng Wang, Weisu Huang, Guoliang Yang, Tiantian Lou, Shiyun Lai, Baiyi Lu, Lufei Zheng
Phytosterols are nutritional phytochemicals that may undergo oxidation and be transformed into phytosterol oxidation products (POPs), thus inducing pathological and toxic effects. This work investigated 4 main phytosterols and 28 POPs in 104 kinds of commercial baked food by using gas chromatography-mass spectrometry. The dietary exposure and hazard index values (HI) associated with POPs from baked food consumption in China were estimated by using Monte Carlo simulation. Concentrations of the total phytosterols were between 3...
September 21, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28933773/rapid-quantification-of-major-volatile-metabolites-in-fermented-food-and-beverages-using-gas-chromatography-mass-spectrometry
#10
Farhana R Pinu, Silas G Villas-Boas
Here we present a method for the accurate quantification of major volatile metabolites found in different food and beverages, including ethanol, acetic acid and other aroma compounds, using gas chromatography coupled to mass spectrometry (GC-MS). The method is combined with a simple sample preparation procedure using sodium chloride and anhydrous ethyl acetate. The GC-MS analysis was accomplished within 4.75 min, and over 80 features were detected, of which 40 were positively identified using an in-house and a commercialmass spectrometry (MS) library...
July 26, 2017: Metabolites
https://www.readbyqxmd.com/read/28933014/size-exclusion-chromatography-ion-mobility-mass-spectrometry-coupling-a-step-toward-structural-biology
#11
Guillaume Van der Rest, Frédéric Halgand
Noncovalent interactions are essential for the structural organization of biomacromolecules in cells. For this reason, the study of the biophysical, dynamic, and architectural interactions among biomacromolecules is essential. Since mass spectrometry requires compatible solutions while preserving the noncovalent bonding network, we envisioned that size exclusion chromatography coupled with ion mobility and mass spectrometry would be a valuable technique to desalt the initial sample and provide solution and gas-phase structural information in a single stage experiment...
September 20, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28932891/identification-of-terpenes-and-essential-oils-by-means-of-static-headspace-gas-chromatography-ion-mobility-spectrometry
#12
Roman Rodríguez-Maecker, Eduardo Vyhmeister, Stefan Meisen, Antonio Rosales Martinez, Andriy Kuklya, Ursula Telgheder
Static headspace gas chromatography-ion mobility spectrometry (SHS GC-IMS) is a relatively new analytical technique that has considerable potential for analysis of volatile organic compounds (VOCs). In this study, SHS GC-IMS was used for the identification of the major terpene components of various essential oils (EOs). Based on the data obtained from 25 terpene standards and 50 EOs, a database for fingerprint identification of characteristic terpenes and EOs was generated utilizing SHS GC-IMS for authenticity testing of fragrances in foods, cosmetics, and personal care products...
September 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28930280/chemical-composition-and-monoterpenoid-enantiomeric-distribution-of-the-essential-oils-from-apharsemon-commiphora-gileadensis
#13
Nativ Dudai, Alona Shachter, Prabodh Satyal, William N Setzer
Background:Commiphora gileadensis (Hebrew: apharsemon) has been used since Biblical times to treat various ailments, and is used today in the traditional medicine of some Middle Eastern cultures. Methods: The essential oils from the stem bark, leaves, and fruits of Commiphora gileadensis-collected at the Ein Gedi Botanical Garden, Israel-were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. In addition, the enantiomeric distributions of the monoterpenoids in the essential oils have been determined by chiral gas chromatography...
September 12, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28930276/essential-oil-of-cymbopogon-citratus-on-the-control-of-the-curvularia-leaf-spot-disease-on-maize
#14
Dalmarcia de Sousa Carlos Mourão, Talita Ferreira de Souza Pereira, Danival José de Souza, Aloísio Freitas Chagas Júnior, Mateus Sunti Dalcin, Ronice Alves Veloso, Evelynne Urzêdo Leão, Gil Rodrigues Dos Santos
The Curvularia Leaf Spot is becoming more common due to the culture expansion and the low resistance of the cultivated genotypes in tropical regions. Thus, the objective was to evaluate the fungitoxicity of the essential oil of Cymbopogon citratus upon the phytopathogen Curvularia lunata, causative agent of the Curvularia Leaf Spot. There was realized pathogenicity tests of C. lunata in maize plants, phytotoxicity of the essential oil of C. citratus and gas chromatography attached, germination tests of the conidia, and of in vitro inhibition of C...
August 20, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28930264/essential-oil-from-piper-aduncum-chemical-analysis-antimicrobial-assessment-and-literature-review
#15
Lianet Monzote, Ramón Scull, Paul Cos, William N Setzer
Background: The challenge in antimicrobial chemotherapy is to find safe and selective agents with potency that will not be compromised by previously developed resistance. Terrestrial plants could provide new leads to antibacterial, antifungal, or antiprotozoal activity. Methods: The essential oil (EO) of Piper aduncum L. (Piperaceae) from Cuba was analyzed by gas chromatography-mass spectrometry (GC-MS). A cluster analysis of P. aduncum EO compositions reported in the literature was carried out. The EO was screened against a panel of microorganisms (bacteria, fungi, parasitic protozoa) as well as for cytotoxicity against human cells...
July 2, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28930251/chemical-profiling-and-evaluation-of-antioxidant-and-anti-microbial-properties-of-selected-commercial-essential-oils-a-comparative-study
#16
Ângelo Luís, Ana Paula Duarte, Luísa Pereira, Fernanda Domingues
Background: The last decades have seen an increased awareness by the scientific community of the extent of resistance to conventional antibiotics, particularly with respect to the emerging multidrug-resistant pathogenic microbes. Additionally, natural antioxidants have received significant attention among food professionals and consumers because of their assumed safety and potential therapeutic value. The aim of this work was to assess the antioxidant activities of eight selected commercial essential oils (EOs), together with the evaluation of their antibacterial and anti-quorum sensing properties...
June 5, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28930244/characterization-and-antioxidant-activity-of-volatile-constituents-from-different-parts-of-aframomum-danielli-hook-k-schum
#17
Emmanuel E Essien, Paul S Thomas, Kelly Oriakhi, Mohammad I Choudhary
Background:Aframomum danielli is used in ethno-medicine for the treatment of several ailments and as a traditional food spice. Methods: The hydro-distilled leaf, stem, seed, rhizome and pod volatile oils of A. danielli were subjected to gas chromatography-mass spectrometry (GC-MS) analysis. Free radical scavenging capacity of the volatile oils was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Results: Thirty-nine (39) volatile compounds were identified in the oils of A...
May 10, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28930243/traditional-small-size-citrus-from-taiwan-essential-oils-bioactive-compounds-and-antioxidant-capacity
#18
Min-Hung Chen, Kai-Min Yang, Tzou-Chi Huang, Mei-Li Wu
Background: The calamondin (Citrus microcarpa Bunge) and the kumquat (Fortunella crassifolia Swingle) are two small-size citrus fruits that have traditionally been consumed in Taiwan; however, there has been a lack of scientific research regarding the active compounds and functionalities of these fruits. Methods: Analysis of volatile composition of essential oil and phytosterol was carried out using Gas Chromatography-Mass Spectrometry (GC-MS). Flavonoid and limonoid were analyzed by High Performance Liquid Chromatography (HPLC)...
May 8, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28930242/essential-oils-from-leaves-of-medicinal-plants-of-brazilian-flora-chemical-composition-and-activity-against-candida-species
#19
Maria da Conceição Mendes Ferreira da Costa, Alexandre Gomes da Silva, Ana Paula Sant'Anna da Silva, Vera Lúcia de Menezes Lima, Patrícia Cristina Bezerra-Silva, Suyana Karolyne Lino da Rocha, Daniela Maria do Amaral Ferraz Navarro, Maria Tereza Dos Santos Correia, Thiago Henrique Napoleão, Márcia Vanusa da Silva, Patrícia Maria Guedes Paiva
Background: The biotechnological potential of medicinal plants from Brazilian Caatinga and the Atlantic Forest has not been extensively studied. Thus, screening programs are important in prospecting for compounds for developing new drugs. The purpose of this study was to determine the chemical composition and to evaluate the anti-Candida activity of essential oils from leaves of Hymenaea courbaril var. courbaril, Myroxylon peruiferum, and Vismia guianensis. Methods: The oils were extracted through hydrodistillation and their chemical compositions were analyzed by gas chromatography coupled with mass spectrometry...
May 3, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28930239/eryngium-foetidum-l-essential-oils-chemical-composition-and-antioxidant-capacity
#20
Paul S Thomas, Emmanuel E Essien, Samuel J Ntuk, Mohammad I Choudhary
Background:Eryngium foetidum essential oils from Nigeria were investigated for the first time in order to ascertain their potency as natural antioxidants. E. foetidum is an aromatic and medicinal herb used in ethno-medicine and as a traditional spice for foods. Methods: The hydro-distilled oils of E. foetidum were subjected to gas chromatography-mass spectrometry (GC-MS) analysis. Free radical scavenging capacity of the volatile oils was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays...
April 28, 2017: Medicines (Basel, Switzerland)
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