Consulta: subjectFacets:"Oxidation"
Registros recuperados: 29
Data/hora: 09/06/2024 10:56:16

Особенности глутатионпероксидной системы в тканях двух цветовых морф черноморской мидии Mytilus galloprovincialis Lam.
Provedor de dados: 13
Autores: Александрова, О. Л.; Солдатов, А. А.; Головина, И. В.
Исследовали содержание продуктов перекисного окисления липидов (ПОЛ) и состояние глутатионпероксидной системы (ГПС) в гепатопанкреасе, жабрах и ноге черноморской мидии Mytilus galloprovincialis Lam. Учитывали две цветовые морфы - черную и коричневую. В ходе исследования выявлена тканевая специфика состояния ГПС и установлена ее зависимость от уровня продуктов ПОЛ. Показано, что наибольшую окислительную нагрузку испытывают жабры. На данном тканевом уровне между моллюсками с разной окраской раковины обнаружены достоверные различия в уровнях активности глугатионпероксидазы (Ш) и глутатионредуктазы (ГР).
Tipo: Journal Contribution
Palavras-chave: Oxidation; Oxidation; Http://aims.fao.org/aos/agrovoc/c_5472.
Ano: 2001
URL: http://repository.ibss.org.ua/dspace/handle/99011/557

Iron oxide formation in the active oxidation front above sapropel S1 in the eastern Mediterranean Sea as derived from low-temperature magnetism
Provedor de dados: 5
Autores: Passier, Hf; Dekkers, Mj.
Low-temperature magnetic properties of eastern Mediterranean sediments from a box-core have been investigated. This box-core contains the present-day oxic-suboxic boundary that is situated at the top of the relic of the youngest sapropel (S1). The upper half of sapropel S1 has been oxidized, and Fe oxides have precipitated in the oxidized sapropel. Zero-field-cooling (ZFC) and field-cooling (FC) saturation remanent magnetization (M-r; induced in a field of 2.5 T at 20 K after cooling from 300 K with or without the 2.5 T field) was measured during warming to 300 K. An M (r) imparted at room temperature (RTSIRM) was cycled to 20 K as well. The difference between ZFC and FC curves around the Verwey transition, as estimated by the parameter delta(FC)...
Tipo: Text
Palavras-chave: Geochemistry; Low-temperature magnetism; Magnetite; Marine sediments; Oxidation; Sediment magnetism.
Ano: 2002
URL: https://archimer.ifremer.fr/doc/00223/33399/31887.pdf

Durability of polydicyclopentadiene under high temperature, high pressure and seawater (offshore oil production conditions)
Provedor de dados: 5
Autores: Le Gac, Pierre-yves; Choqueuse, Dominique; Paris, Marc; Recher, G.; Zimmer, Celine; Melot, D.
In the offshore industry polymer coatings are widely used to ensure thermal insulation of steel pipes, and to avoid over-cooling of the hot oil inside. Because of very severe service conditions (i.e. high temperature, high pressure and presence of seawater) and an expected life time of 20 years, durability of these coatings is a major issue for this industry. Polypropylene and polyurethane are often used for this application, nevertheless these polymers have some limitations in terms of processing time for polypropylene and maximum service temperature for polyurethane. Polycyclopentadiene (pDCPD) shows good processing characteristics and low thermal conductivity, so this polymer could be a good alternative coating in the offshore industry, but the...
Tipo: Text
Palavras-chave: Polydicyclopentadiene; Seawater; Accelerated ageing; Oxidation; Offshore; Field joint.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00114/22534/20233.pdf

Predictive ageing of elastomers: Oxidation driven modulus changes for polychloroprene
Provedor de dados: 5
Autores: Le Gac, Pierre-yves; Celina, Mathew; Roux, Gerard; Verdu, Jacques; Davies, Peter; Fayolle, Bruno.
The oxidative ageing in the range of 60 °C–140 °C of sulfur vulcanized polychloroprene has been studied by FTIR spectroscopy (double bond consumption), modulus changes and oxygen absorption measurements. Experiments were carried out on thin films and thick samples to investigate both homogeneous and inhomogeneous (diffusion controlled) oxidation with the goal of establishing the underlying correlation between oxidative degradation chemistry and mechanical property changes. A correlation between oxidatively driven degradation chemistry and modulus is possible using the established approaches of rubber elasticity where an effective crosslinking yield due to double bond reactions is of the order of 30% for this material (i.e. the loss of 3 double bonds...
Tipo: Text
Palavras-chave: Polychloroprene; Ageing; Sulfur vulcanization; Oxidation; Kinetic modeling; Modulus changes.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00342/45323/44784.pdf

Role of strain induced crystallization and oxidative crosslinking in fracture properties of rubbers
Provedor de dados: 5
Autores: Le Gac, Pierre-yves; Broudin, Morgane; Roux, Gérard; Verdu, Jacques; Davies, Peter; Fayolle, Bruno.
Tensile properties and crack propagation properties, especially critical strain energy release rate in mode I, GIC, have been used to investigate fracture properties of elastomers and their relationships with microstructure. These investigations were mainly based on a series of comparisons: first, the behaviour of polychloroprene rubber (CR), undergoing stress hardening due to strain induced crystallization (SIC) and oxidative crosslinking (OCL) was compared with that of chlorinated polyethylene (CPE), which undergoes SIC but not OCL, and with a polyurethane based on hydroxyl terminated polybutadiene (PU) which undergoes OCL but not SIC. Comparisons were also made on CR between fracture behaviour at ambient temperature, where SIC occurs and at 100°C where...
Tipo: Text
Palavras-chave: Fracture; Rubber; Oxidation.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00184/29546/27872.pdf

Metabolism of CO and CH sub(4) by nitrifiers and the determination of the nitrification rate.
Provedor de dados: 5
Autores: Morita, R; Jones, R.
The nitrifying bacteria were found to survive 24 weeks in the absence of ammonium without decreasing their number of cell size. Because H sub(2), CO, and CH sub(4) are present in the marine environment, these substrates were investigated as a possible source of the energy of maintenance for the nitrifying bacteria. super(14)CO and super(14)CH sub(4) were found to be oxidized by the nitrifiers. N-serve was found to inhibit the oxidation of CO. Using the nitrifiers' ability to oxide CO, a method for the determination of the nitrification rate was developed. The ability of nitrifiers to oxidize CO may play a significant role in the cycling of CO sub(2) in the marine environment. Whether CO and CH sub(4) oxidation play a role in the survival of nitrifiers in...
Tipo: Text
Palavras-chave: Methane; Carbon dioxide; Survival; Bacteria; Nitrification; Nitrogen cycle; Oxidation; Carbon cycle; Biogeochemistry; Metabolism.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-975.pdf

Magnetic properties and geochemistry of the active oxidation front and the youngest sapropel in the eastern Mediterranean Sea
Provedor de dados: 5
Autores: Passier, Hf; De Lange, Gj; Dekkers, Mj.
Magnetic properties (IRM, ARM, chi (in), S-ratio at 0.3 T, room temperature (RT) hysteresis and thermomagnetic curves) and geochemical data (Fe, S, Mn, Al, Ti, organic C) were studied in two eastern Mediterranean boxcores (ABC26 and BC19) at a resolution of 3-5 mm. The boxcores contain sapropel S1 (9-6 kyr BP) at a few decimetres below seafloor. The magnetic fraction consists predominantly of single-domain (SD) to pseudo-single-domain (PSD) magnetite in the entire cores. The original input of magnetic grains comes from two sources: aeolian dust (both cores) and volcanic ash from the Minoan eruption of Santorini (core BC19 only). Non-steady-state diagenesis has changed the magnetic mineralogy considerably in these alternating organic-rich /organic-poor...
Tipo: Text
Palavras-chave: Geochemistry; Magnetite; Marine sediments; Mediterranean Sea; Oxidation; Sediment magnetism.
Ano: 2001
URL: https://archimer.ifremer.fr/doc/00221/33184/31805.pdf

Oxidation of unvulcanized, unstabilized polychloroprene: a kinetic study
Provedor de dados: 5
Autores: Le Gac, Pierre Yves; Roux, Gerard; Verdu, Jacques; Davies, Peter; Fayolle, Bruno.
Thermal oxidation in air at atmospheric pressure, in the 80-140°C temperature range and in oxygen at 100°C in the 0.02-3 MPa pressure range, of unvulcanized, unstabilized, unfilled polychloroprene (CR) has been characterized using FTIR and chlorine concentration measurement. The kinetic analysis was focused on double bond consumption. A mechanistic scheme involving unimolecular and bimolecular hydroperoxide decomposition, oxygen addition to alkyl radicals, hydrogen abstraction on allylic methylenes, alkyl and peroxyl additions to double bonds and terminations involving alkyl and peroxy radicals was elaborated. The corresponding rate constants were partly extracted from the literature and partly determined from experimental data using the kinetic model...
Tipo: Text
Palavras-chave: Polychloroprene; Oxidation; Radical chain; Kinetics.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00199/31010/29413.pdf

Comment protéger les acides gras polyinsaturés à longues chaînes oméga 3 (AGPI -- LC ω3) vis-à-vis de l’oxydation ?
Provedor de dados: 5
Autores: Genot, Claude; Eymard, Sylvie; Viau, Michèle.
Increase the consumption of long-chain omega 3 polyunsaturated fatty acids (LC ω3 PUFA) is highly recommended for their health benefits. However, these fatty acids are very prone to oxidation, which can impair sensory, nutritional and functional properties of foods. In this paper the various ways that increase LC ω3 PUFA stability during processing and storage of food products are reviewed. To efficiently protect LC ω3 PUFA during processing and storage of foods, a combined strategy, taking into account both the matrix and the process should be undertaken. First the quality of the raw materials should be rigorously controlled by, for example, increasing contents of in situ antioxidants and decreasing length of storage. Then, during processing and storage...
Tipo: Text
Palavras-chave: Oxidation; Lipids; Omega 3 polyunsaturated fatty acids; Antioxidants process; Formulation; Structure.
Ano: 2004
URL: https://archimer.ifremer.fr/doc/00480/59157/61786.pdf

Modifications d'un exopolysaccharide biosynthétisé par une bactérie issue des écosystèmes Hydrothermaux profonds
Provedor de dados: 5
Autores: Petit, Anne-celine.
Le travail présenté dans ce mémoire concerne la modification d'un exopolysaccharide (EPS), l'HYD 657, biosynthétisé par une bactérie issue des écosystèmes hydrothermaux profonds. Ce polysaccharide d'un poids moléculaire de 1,8.106 Da est composé de 40-50% d'oses neutres et de 30- 40% d'acides uroniques. L'hypothèse de structure la plus probable décrit son unité de répétition comme un undécasaccharide possédant 3 ramifications courtes. Cet EPS, sous sa forme native, a déjà fait l'objet d'une étude approfondie en vue d'applications dans le domaine de la cosmétique pour ses propriétés apaisantes en application topique cutanée.  Pour élargir le spectre d'applications de cet EPS, la réduction de sa masse molaire a été envisagée.  La première partie décrit la...
Tipo: Text
Palavras-chave: Oxidation; Sulfation; Esterification; Metallic catalysts; Sonochemistry; Deep sea hydrothermal; Depolymerization; Exopolysaccharide; Oxydation; Sulfatation; Estérification; Catalyse métallique; Ultrasons; Source hydrothermale; Dépolymérisation; Exopolysaccharide.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/these-1232.pdf

Changes in proximate composition and lipid quality of atherina atherina sp. during sun drying process
Provedor de dados: 20
Autores: Selmi, S.; Bouriga, N.; Faure, E.; Trabelsi, M.
Dans le présent travail, l’effet du séchage solaire sur la composition biochimique et la qualité des lipides des athérines a été étudié. La teneur en lipides, protéines et en cendres dans l’athérine a augmenté significativement (p &lt;0.05) après le séchage. Cependant, celle de l’humidité a montré une  forte diminution pour atteindre 22.37% dans le produit final. D’autre part, l’étude des indicateurs d’altération des lipides (Oxydation et Hydrolyse) nous a montré que la qualité des lipides des athérines est affectée par ce type de traitement. En effet, les taux des hydropéroxydes et des acides gras libres ont augmenté significativement (p &lt; 0.05) après le séchage pour atteindre respectivement 2.02 meq active O2/kg huile et 3.67%. La formation des...
Tipo: Journal Contribution
Palavras-chave: Biochemical composition; Dried products; Drying; Hydrolysis; Methodology; Oxidation; Processing fishery products; Quality assurance; Atherina; Http://aims.fao.org/aos/agrovoc/c_688.
Ano: 2008
URL: http://hdl.handle.net/1834/4152

Change in lipids quality and fatty acids profile of two small pelagic fish: sardinella aurita and sardina pilchardus during canning process in olive oil  and tomato sauce respectively
Provedor de dados: 20
Autores: Sadok, S.; Selmi, S.
لدراسة تأثير عملية تحويل سمك السردين واللاطشة  إلى المعلبات على الجودة الغذائية، قمنا بمتابعة موشرات جودة الدهنيات و تركيبتها  من الأحماض الدهنية و أثبتت النتائج أن تغيرات كمية و جودة الدهنيات متعلقة أساسا بتركيبة سمك السردين أو اللاطشة  الطازج بالدهنيات و بتركيبة المادة الحافظة (زيت الزيتون أو الطماطم). كما أثبتت التحاليل بواسطة الكروماتوغرافيا ذات الطور الغازي ثراء المعلبات بالأحماض الدهنية التالية C18 :1 ω9 وC18 :2 ω6 . وأخيرا، يمكننا التأكيد أن سمك السردين واللاطشة  المعلب بزيت الزيتون و الطماطم غني بالأحماض الدهنية من عائلتيωω3 وω6 .
Tipo: Journal Contribution
Palavras-chave: Sardina pilchardus  Sardinella aurita; Canning; Lipids; Oxidation; Polyunsaturated fatty acids; Processing fishery products; Quality control; Oxidation; Canning; Lipids; Polyunsaturated fatty acids; Http://aims.fao.org/aos/agrovoc/c_5472; Http://aims.fao.org/aos/agrovoc/c_1260; Http://aims.fao.org/aos/agrovoc/c_4362; Http://aims.fao.org/aos/agrovoc/c_29254.
Ano: 2007
URL: http://hdl.handle.net/1834/4286

Kinetics of iron (II) oxidation in seawater of various pH
Provedor de dados: 27
Autores: Roekens, E.J.; Van Grieken, R.E.
The rate of iron(II) oxidation in the North Sea water of pH 5.5-10 in the range 10-25°C has been studied. The oxygenation rate depends linearly on the iron(II) and dissolved oxygen concentrations. The second-order dependence on (OH&lt;sup&gt;-&lt;/sup&gt;), found by several investigators for synthetic solutions, was confirmed in seawater, but only for pOH&gt;6.9. For pOH&lt;5.9 the rate appeared to be independent of the pOH. In the intermediate range, pOH&lt;5.9-6.9, corresponding to the natural pH of seawater, a first-order dependence on the pOH is obeyed. The important discrepancy in the literature between the second-order rate constant for NaCHO&lt;sub&gt;3&lt;/sub&gt; solutions and for seawater can be attributed predominantly to the incorrect...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Iron; Kinetics; Oxidation.
Ano: 1983
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3293

Stabilization of Rice Bran in Broiler Feed with Natural and Synthetic Antioxidants and Heat Treatment
Provedor de dados: 89
Autores: Gopinger,E; Krabbe,EL; Avila,VS De; Surek,D; Lopes,LS.
ABSTRACT The objective of this study was to evaluate different strategies for the oxidative stabilization of rice bran (RB) in the diet of broiler chickens using natural antioxidant additives, synthetic antioxidant additives and heat treatment on performance, breast meat quality and liver fat content and the nutrient digestibility coefficients. Furthermore, the study aimed to evaluate the effects of heat treatment and antioxidants, antioxidant additive treatments, without antioxidants, natural, and synthetic, and to three heat treatments, without heat, dry-heat and moist-heat, after the rice bran was stored for 90 days and then incorporated into the experimental diets. 1080 broilers were arranged in a 3 x 3-factorial randomized design with 10 replicates...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alternative feedstuff; Meat quality; Poultry; Oxidation; Digestibility.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2019000400321

Effec t of Freeze-Thaw Cycles on Lipid Oxidation and Myowater in Broiler Chickens
Provedor de dados: 89
Autores: Ali,S; Rajput,N; Li,C; Zhang,W; Zhou,G.
ABSTRACT The present study was carried out to investigate the influence of freezing-thawing cycles (0, 2, 4 and 6) on lipid oxidation and myowater contents and distribution. Nine replicates of chicken breast meat samples were used for each cycle. Lipid oxidation was determined by measuring peroxide value, and malondialdehyde (MDA) concentrations, which reflect thiobarbituric acid reactive substance (TBARS). Color was determined with a digital colorimeter. Muscle moisture contents were determined by drip loss and thawing loss, water holding capacity, and nuclear magnetic resonance (NMR). The results showed that, as the number of freeze-thaw cycles increased, meat redness decreased and MDA and peroxide values increased. Drip loss and thawing loss tended to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Freeze-thaw cycles; Chicken meat; Oxidation; Drip loss; Color.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2016000100035

Oil blends with sesame oil in fish diets: oxidative stress status and fatty acid profiles of lambari
Provedor de dados: 96
Autores: Natori,Mariene Miyoko; Oliveira,Ricardo Henrique Franco de; Parisi,Giuliana; Bonelli,Antonio; Melo,Mariza Pires de; Viegas,Elisabete Maria Macedo.
ABSTRACT The objective of this research was to evaluate the growth performance, oxidative stress, and fatty acid profiles of lambari (Astyanax altiparanae) fed diets containing different lipid sources: soybean oil, linseed oil, and freshwater fish residue oil combined or otherwise with sesame oil (SEO). The fish (mean weight 0.95±0.46 g; mean length 4.21±2.77 cm) were distributed into 24 cages (cage capacity: 0.70 m3; fish density: 276 individuals m−3) in six treatments and four replicates. After 80 days of feeding, they were weighed, and samples were collected for assay of catalase, glutathione reductase (GR), and lactate dehydrogenase (LDH) enzyme activities in muscle and analysis of the fatty acid profiles of polar and neutral fractions of whole...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish; Lipid; Nutrition; Oxidation.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982019000100150

Performance, carcass and meat quality of ewes supplemented with magnesium oxide
Provedor de dados: 96
Autores: Constantino,Camila; Ribeiro,Edson Luis de Azambuja; Bridi,Ana Maria; Tarsitano,Marina Avena; Castro,Filipe Alexandre Boscaro de; Fernandes Júnior,Francisco; Mizubuti,Ivone Yurika; Pereira,Elzânia Sales.
The objective of this study was to evaluate the performance, the carcass and meat characteristics of ewes supplemented with magnesium oxide. Eighteen 6-year-old Santa Ines ewes were used in a completely randomized experimental design, where three levels of supplementation (0.0, 0.1 and 0.2% magnesium oxide in the concentrate) were tested, with six replicates. Final weight, weight gain, feed intake and feed conversion were not affected by levels of magnesium supplementation. Hot and cold carcass weights showed linear increasing and quadratic responses, respectively, according to supplementation with magnesium. Carcass measurements such as length, depth, and measures of arm and leg were not affected by supplementation. Depth and width of the longissimus...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Marbling; Myofibrillar fragmentation index; Oxidation; Production; Sheep.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982014000100005

Effect of storage on fatty acid profile of butter from cows fed whole or ground flaxseed with or without monensin
Provedor de dados: 96
Autores: Silva-Kazama,Daniele Cristina da; Santos,Geraldo Tadeu dos; Pintro,Paula Toshimi Matumoto; Visentainer,Jesuí Vergílio; Kazama,Ricardo; Petit,Hélène Véronique; Marchi,Francilaine Eloise de.
Eight Holstein cows with body weight 570 ± 43 kg and 60 ± 20 lactation days were distributed in a double Latin square design with four 21-day periods to determine the effects of feeding ground or whole flaxseed with or without monensin supplementation (0.02% on a dry matter basis) on fatty acid profile of butter stored for 15 and 45 days. Ground flaxseed supply, in comparison to whole flaxseed, reduced relative percentages of 16:0, cis7-16:1, 17:0, and cis10-17:1 but it increased those of cis9,trans11-18:2, cis3-18:3, and omega 3 fatty acids in butter fat, reducing relative percentage of medium-chain fatty acids and increasing the content of polyunsaturated fatty acids. Supplementation with monensin increased relative percentages of cis9,trans11-18:2 and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Butter; Dairy cow; Fatty acid; Flaxseed; Oxidation.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010001000028

Oxidative stability of biodiesel from soybean oil fatty acid ethyl esters
Provedor de dados: 63
Autores: Ferrari,Roseli Ap.; Oliveira,Vanessa da Silva; Scabio,Ardalla.
Biodiesel consists of long-chain fatty acid esters, derived from renewable sources such as vegetable oils, and its utilization is associated to the substitution of the diesel oil in engines. Depending on the raw material, biodiesel can contain more or less unsaturated fatty acids in its composition, which are susceptible to oxidation reactions accelerated by exposition to oxygen and high temperatures, being able to change into polymerized compounds. The objective of this work was to determine the oxidative stability of biodiesel produced by ethanolysis of neutralized, refined, soybean frying oil waste, and partially hydrogenated soybean frying oil waste. The evaluation was conducted by means of the Rancimat® equipment, at temperatures of 100 and 105ºC,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rancimat®; Transesterification; Oxidation.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000300014

Lipid profile and oxidative stability of beef cuts from Urabá (Antioquia, Colombia): A step towards global commercialization
Provedor de dados: 109
Autores: Restrepo-Molina,Diego Alonso; Álvarez-Henao,María Victoria; Rojano,Benjamín; Alzate-Arbeláez,Andrés Felipe; Duarte-Correa,Yudy.
Abstract The commercialization of beef is an activity of great relevance for the department of Antioquia (Colombia), particularly in the Urabá region. The objective of this study was to evaluate the fat content, lipid composition, and some indicators of lipid oxidation and protein in beef from the Urabá region. 72 samples of beef cuts (loin and neck) of categories 3, 4 and 5 stars were analyzed. There were no statistical differences (p &gt; 0.05) between the fat content of cuts from the neck (11.64 ± 7.25 %) and loin (10.49 ± 5.60 %), or in the amount of saturated, monounsaturated, and polyunsaturated fat. There was no difference between the samples evaluated for lipid oxidation (TBARS). The lowest protein oxidation (4.48 ± 0.21 nmol carbonyl compounds/mg...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lipid content; Oxidation; Stability; Meat; Fat.
Ano: 2022
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122022000300240

In vitro callogenesis induction of Guarianthe skinneri (Bateman) Dressler &amp;amp; W.E. Higgins (Orchidaceae)
Provedor de dados: 109
Autores: Coutiño-Cortés,Ana Gabriela; Bertolini,Vincenzo; Iracheta-Donjuan,Leobardo; Ruíz-Montoya,Lorena; Valle-Mora,Javier Francisco.
Abstract: Guarianthe skinneri (Bateman) Dressler &amp; W.E. Higgins, is a native orchid from Mexico, considered as threatened species in the NOM-ECOL-059-SEMARNAT-2010, mainly due to the disappearance of its natural habitat and illegal collection during the flowering season. The aim of this research was to induce in vitro callogenesis using different types of explants and phytoregulators, in order to establish a mass production technique as a contribution to the conservation of this species. We evaluated leaf and pseudobulb pith explants growing in semi-solid medium MS, adding BAP, 2, 4-D, Kin, the combination of BAP/2 and 4-D/Kin/Sad and a control without any type of plant growth regulators. Statistical analysis showed that pseudobulb pith explants are...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biodiversity conservation; Cell division; Oxidation; Phytoregulator.
Ano: 2017
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122017000200254

Surface modification of activated carbon by corona treatment
Provedor de dados: 42
Autores: PEGO,MATHEUS F.F.; BIANCHI,MARIA LÚCIA; CARVALHO,JANAÍNA A.; VEIGA,TAIS R.L.A.
Surface modification may lead activated carbon (AC) to take on different properties. This study aimed to promote surface modification of activated carbons using corona treatment (electrical discharge). In this study, powdered commercial activated carbon was used. Activated carbons were subjected to corona treatment at different exposure times (2, 5, 8 and 10 min) at 4.5 cm height from the source. To observe differences promoted by treatment, activated carbons were analyzed by acidity, surface functional groups, Fourier Transform Infrared Spectroscopy (FTIR), elemental analysis (CHN), proximate analysis and thermogravimetry. Corona treatment impacted surface chemistry of activated carbons. There was a trend of increasing surface acidity according to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chemical reactions; Electric discharge; Oxidation; Surface chemistry.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000100402

Signal transduction and gene expression regulated by calcium release from internal stores in excitable cells
Provedor de dados: 48
Autores: CARRASCO,MARÍA ANGÉLICA; JAIMOVICH,ENRIQUE; KEMMERLING,ULRIKE; HIDALGO,CECILIA.
Calcium regulation of several transcription factors involves different calcium-dependent signaling cascades and engages cytoplasmic as well as nuclear calcium signals. The study of the specific sources of calcium signals involved in regulation of gene expression in skeletal muscle has been addressed only recently. In this tissue, most cytoplasmic and nuclear calcium signals originate from calcium release from internal stores, mediated either by ryanodine receptor (RyR) or IP3 receptor (IP3R) channels. The latter are located both in the sarcoplasmic reticulum (SR) and in the nuclear membrane, and their activation results in long-lasting nuclear calcium increase. The calcium signals mediated by RyR and IP3R are very different in kinetics, amplitude and...
Tipo: Journal article
Palavras-chave: Calcium signals; Intracellular stores; Transcription; Oxidation; Neurons; Skeletal muscle.
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602004000400028

Interaction of Olive Oil Phenol Antioxidant Components with Low-density Lipoprotein
Provedor de dados: 48
Autores: LAMUELA-RAVENTÓS,ROSA M; GIMENO,EVA; FITÓ,MONTSE; CASTELLOTE,ANA-ISABEL; COVAS,MARIBEL; DE LA TORRE-BORONAT,M. CARMEN; LÓPEZ-SABATER,M. CARMEN.
Phenolic compounds have shown to inhibit LDL oxidation in vitro and ex vivo; however, they are hydrosoluble compounds while LDL is a lipoprotein. Analysis of phenolic compounds in LDLs by HPLC is necessary to demonstrate their binding capacity to lipoproteins. We developed and validated a solid phase extraction method (SPE) that allowed us the purification of LDL samples and their analysis by HPLC. This methodology allowed us to demonstrate the in vitro binding capacity of tyrosol, one of the main phenolic compounds in olive oil, to LDL. In the intervention dietary study with volunteers, food rich in phenolic compounds affected LDL composition. Changes in LDL phenolics composition are not observed after the short-term ingestion of food rich in phenolic...
Tipo: Journal article
Palavras-chave: Antioxidant; LDL; Olive oil; Oxidation; Phenol; Tyrosol.
Ano: 2004
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602004000200011

Rosemary and Pitanga Aqueous Leaf Extracts On Beef Patties Stability under Cold Storage
Provedor de dados: 52
Autores: Vargas,Flávia Carolina; Arantes-Pereira,Lucas; Costa,Patrícia Argemira da; Melo,Mariza Pires de; Sobral,Paulo José do Amaral.
ABSTRACT Because processing and storage conditions affect several beef quality attributes, the food industry uses a variety of synthetic antioxidants. However, some synthetic antioxidants have been questioned regarding its safety, and thus the interest in using natural antioxidants in food products is increasing. This paper aimed at assessing leaf aqueous extracts of Rosemary (Rosmarinus officinalis Linnaeus) and Pitanga (Eugenia uniflora Linnaeus) as antioxidants in beef cold storage. After 48h storage, patties added of Rosemary leaf extracts showed increased pH. Patties added of Pitanga extracts had the lowest a* color values. Oxymyoglobin levels were significantly higher for Negative control, than for Pitanga treatment. The 10% extract addition...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Antioxidant; Myoglobin; Color; Oxidation; Lipid.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000100514

Allantoin as an independent marker associated with carotid intima-media thickness in subclinical atherosclerosis
Provedor de dados: 56
Autores: Santana,M.S.; Nascimento,K.P.; Lotufo,P.A.; Benseñor,I.M.; Meotti,F.C.
Allantoin is the main product of uric acid oxidation and was found to be augmented in atherosclerotic plaque in human autopsy and in animal models of atherosclerosis. Uric acid is abundant in human plasma and is prone to oxidation in inflammatory conditions such as atherosclerosis. In this study, we found a significant increase in plasma uric acid (P=0.002) and allantoin (P=0.025) in participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) that presented common carotid intima-media thickness (c-IMT) within the 75th percentile (c-IMT≥P75). Multiple linear regression showed an association of c-IMT with uric acid (β=0.0004, P=0.014) and allantoin (β=0.018, P=0.008). This association was independent of age, the traditional risk factor...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Allantoin; Uric acid; Common carotid intima-media thickness; Atherosclerosis; Oxidation.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2018000800613

Pomegranate (Punica granatum L.) peel lyophilized extract delays lipid oxidation in tuscan sausages
Provedor de dados: 65
Autores: Zago,Gilberto Rogério; Gottardo,Franciele Maria; Bilibio,Denise; Freitas,Carla Patrícia; Bertol,Charise Dallazem; Dickel,Elci Lotar; Santos,Luciana Ruschel dos.
ABSTRACT: Pomegranate (Punica granatum L.) contains a high concentration of antioxidant and phenolic compounds. Pomegranate peel extracts at different concentrations were used as natural antioxidant to increased the lipid stability of fresh Tuscan sausages, comparing with sodium erythorbate (SE). Peels were subjected to ultrasound-assisted aqueous extraction and lyophilization. The extract was previously characterized throught phenol and flavonoids determination. The Tuscan Sausages were prepared, and color, pH, peroxides, and thiobarbituric acid reactive substances were assessed at 1, 15, and 30 days of storage, at a mean temperature of 5 ± 1 ºC and under a 12-hour light cycle/day. Sausages containing 0.05 and 0.1% of peel extract showed results similar...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Meat product; Lipid; Oxidation; Storage; Sensory analysis.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000400753

Fate of allelochemicals in the soil
Provedor de dados: 65
Autores: Vidal,Ribas Antonio; Bauman,Thomas Trost.
Allelochemicals are compounds released by one plant or plant residues that may have a negative or positive effect on other plant. The importance of allelopathy was extensively explored during the past three decades, with the work concentrating in the extraction and identification of the chemicals, and demonstration of activity in petry dish experiments. These compounds interact in the soil environment similarly as herbicides and are subject to processes of degradation such as microbial degradation, oxidation, and photolysis, and processes of removal or transfer, such as volatilization and adsorption. The objective of this review was to access the fate of allelochemicals in the soil environment to help to find strategies to increase its activity. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Adsorption; Allelopathy; Oxidation; Photolysis; Plant interference; Volatilization.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84781997000200032

Refrigerated storage of pork meat sprayed with rosemary extract and ascorbic acid
Provedor de dados: 65
Autores: Perlo,Flavia; Fabre,Romina; Bonato,Patricia; Jenko,Carolina; Tisocco,Osvaldo; Teira,Gustavo.
ABSTRACT: There is an increasing consumer demand to avoid the use of synthetic additives like many antioxidants currently added to food. The objective of this study was to determine the effect of spraying ascorbic acid, rosemary extract and a combination of both on pork meat during refrigerated storage. Pork meat with antioxidants sprayed on the surface was packaged under vacuum and stored (4ºC, 45d). pH, color, lipid oxidation, total aerobic count, drip loss and moisture were evaluated during storage. Results suggested that surface application of rosemary extract and a combination of rosemary extract and ascorbic acid resulted in an effective delay of lipid oxidation of pork meat, without affecting pH, colour or water content during storage. No effect of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Natural antioxidants; Oxidation; Storage; Meat quality.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018000400751