Search results for " composition"
showing 10 items of 1437 documents
The relationship between feed intake behaviour with intramuscular fat, cholesterol and fatty acid composition in pork
2011
The aim of this study was to investigate the phenotypic relationship between feed intake (FI) characteristics with intramuscular fat, cholesterol and fatty acid composition in pork. Data were available on 202 Duroc barrows. Intramuscular fatness was positively correlated with a higher percentage of saturated (SFA) and monounsaturated fatty acids (MUFA), a lower percentage of polyunsaturated (PUFA), omega-3 (ω3) and omega-6 (ω6) fatty acids, and a lower ω6/ω3 and P:S ratio (p < 0.05). Faster growth resulted in a higher level of SFA and a lower level of ω3 fatty acids (p < 0.05). Increased FI, residual feed intake (RFI) and feed intake time (TIME) and a decreased feed intake frequency (FREQ) …
Polymer-coated reversed-phase packings with controlled hydrophobic properties
1992
Abstract We have designed and synthesized novel reversed-phase packings of non-porous and porous polymethacrylate-coated silicas. By varying the hydrophobicity of the polymer coating, selective unfolding of polypeptides may be achieved, thus enabling manipulation of the chromatographic profile. This study characterizes these packings through their employment for separations of model synthetic peptides of defined secondary, tertiary and quaternary structure. Thus, the packings were applied to the reversed-phase separation α-helical amphipathic and non-amphipathic peptides of the same amino acid composition but different sequences. In addition, selective unfolding of model to-stranded α-helic…
Imprinted chiral stationary phases in high-performance liquid chromatography
2001
Polymers imprinted with chiral templates offer a new generation of tailor-made chiral stationary phases (CSPs) with predictable selectivities. This review summarizes the present state of the art of molecular imprinting to generate tailor-made CSPs and provides an overview of the main factors involved in the manufacturing process that are crucial to the chromatographic performance of the phases.
Distribution of Δ5-olefinic acids in the triacylglycerols fromPinus koraiensisandPinus pinasterseed oils
1996
Purified triacylglycerols (TAG) fromPinus koraiensis andP. pinaster seed oils, which are interesting and commercially available sources of Δ5-olefinic acids (i.e.,cis-5,cis-9,cis-12 18:3 andcis-5,cis-11,cis-14 20:3 acids) were fractionated by reversed-phase high-performance liquid chromatography, and each fraction was examined by capillary gas-liquid chromatography for its fatty acid composition. A structure could be assigned to more than 92% of TAG from both oils. In both instances, ca. 48% of the TAG were shown to contain at least one δ5-olefinic acid. In the great majority of TAG, our data showed that there is only one molecule of δ5-olefinic acid per molecule of TAG. This is compatible …
Effect of pHand age of culture on cellular fatty acid composition of Leuconostoc oenos
1996
Z. DRICI-CACHON, J.F. CAVIN AND C. DIVIES. 1996. This study is concerned with the fatty acid composition of three strains of Leuconostoc oenos grown at different pH. The most abundant fatty acids were C18: 1w9, C19: 0 cy(w9,10) and C16:0, followed by C16: 1w9 and C14: 0. The pH considerably modified the fatty acid distribution in Lo107 (an acidophilic strain) and Lo8413 (a moderately acidophilic strain). However, moderate changes occurred for LoATCC 23277 (a less acidophilic strain). At pH 2.9, Lo107 has a remarkably high level of C19: 0 cy-(w9,10) and C19:0 cy(w11,12). Proportions of C18: 1 and C19:0 cyclo acids varied mainly with the pH of the medium and also as a function of growth phase…
The PAH composition in limpets (Patella vulgate L.) from the coasts of Sicily (Italy)
2006
This article examines the presence, distribution, nature and sources of 19 Polycyclic Aromatic Hydrocarbons (PAH), in Patellae (patella vulgate L.) and seaweed (vulva) sampled in different stations of Sicilian coastal environments and analyzed for their polycyclic aromatic hydrocarbon (PAH) content. Analysis was performed by gas chromatography/mass spectrometry (GC/MS) with selected ion monitoring (SIM), after saponification of the sample and clean up of the extract. In the limpets the total concentration of polycyclic aromatic hydrocarbons ranged from 34 to 750 μg/Kg of dry matrix. The relative standard deviation (RSD) of the replicas on the concentrations of individual compounds ranged fr…
Fatty Acid Composition in the Lipids of some Marine Chiorococcales and Eustigmatales
1989
Abstract The fatty acid composition in the lipids of six coccoid microalgae species (≈ 2 μm in diameter) was investigated. In addition to analyses of ultrastructure and pigment content, lipid composition is shown to be a chemotaxonomic tool in the classification of algae. The four species of Chiorococcales (Chlorophyceae) - the marine species as well as the fresh water species, both kept in artificial seawater - contain a fatty acid composition resembling that of Chlorella spp. and of green leaves of higher plants. The fatty acid pattern is characterized as lacking in C20 acids but containing large amounts of C 16 and C 18 polyunsaturated fatty acids, hexadecatrienic acid (16 :3) and a-lino…
Characterization of a fiber-reinforced new fully aromatic liquid crystalline polymer
1998
A new rigid liquid crystalline polymer that demonstrates good mechanical and thermomechanical properties and acceptable processing temperature has been recently synthesized and characterized. The melting temperature and some thermomechanical properties do not seem, however, suitable for use in some applications at high temperature or in the presence of aggressive fluids. The use of appropriate inorganic fillers can overcome these shortcomings. In this work the new LCP, polymerized in a bench-scale apparatus, and the same sample filled with carbon fibers are characterized. The properties of the carbon fiber filled LCP are compared with those of another filled wholly aromatic commercial LCP,…
Relationships between metabolic fluxes and enzyme amino acid composition
2013
AbstractMetabolic fluxes are a key parameter of metabolic pathways being closely related to the kinetic properties of enzymes and could be conditional on their sequence characteristics. This study examines possible relationships between the metabolic fluxes and the amino acid (AA) composition (AAC) for enzymes from the yeast Saccharomyces cerevisiae glycolysis pathway. Metabolic fluxes were quantified by the COPASI tool using the kinetic models of Hynne and Teusink at 25 mM, 50 mM, and 100 mM of external glucose or employing literature data for cognate kinetic or stoichiometric models. The enzyme sequences were taken from the UniProtKB, and the AAC computed by the ExPASy/ProtParam tool. Mul…
Effect of Heating Time and Temperature on the Chemical Characteristics of Biochar from Poultry Manure
2014
Poultry manure (PM) chars were obtained at different temperatures and charring times. Chemical-physical characterization of the different PM chars was conducted by cross-polarization magic angle spinning (CPMAS) (13)C NMR spectroscopy and thermal analysis. CPMAS (13)C NMR spectra showed that the chemical composition of PM char is dependent on production temperature rather than on production duration. Aromatic and alkyl domains in the PM chars obtained at the lowest temperatures remained unchanged at all heating times applied for their production. The PM char obtained at the highest temperature consisted only of aromatic structures having chemical nature that also appeared invariant with hea…