RESUMEN
Energy is a major cost component in diets for poultry. We hypothesized that the supplementation of emulsifier blends in broiler diets may contribute to the efficient utilization of energy and in increasing fat digestibility, thereby improving performance. To test our hypothesis, an experiment was conducted to evaluate the effect of a blend of emulsifiers on growth performance, nutrient digestibility, serum lipid profiles, and meat quality of broilers. A total of 768 1-d-old Ross 308 male broiler chicks with an average initial body weight of 45.55 ± 0.34 g were used in a 35 days feeding trial. Broilers were sorted into 4 treatments, 12 replications per treatment, and 16 birds per pen. Dietary treatments consisted of corn-soybean meal based basal diet and the basal diet supplemented with 0.05%, 0.075%, and 0.10% emulsifier. As a result of this study, the inclusion of 0.05%, 0.075%, and 0.10% emulsifier blends (sodium stearoyl-2-lactylate (SSL) and Tween 20) in the basal diet linearly increased (P = 0.0001) body weight gain (BWG) and improved feed conversion ratio (FCR) (linear effect P = 0.0001) on d 7 to 21, d 21 to 35 as well as overall. Broilers fed with different levels of emulsifier blends also showed a linear increment (P < 0.05) in dry matter (DM) and fat digestibility. A trend of linear reduction (P = 0.051) in low density lipoprotein (LDL) in the serum of broilers fed emulsifier blend was observed. The lightness value of breast muscle color linearly increased (P = 0.001), the redness and yellowness values tended to increase (P = 0.072 and P = 0.094 respectively), and the water holding capacity (WHC) showed trends in reduction (P = 0.078) with an increase in the level of emulsifier blends. With regards to relative organ weight, spleen weight was linearly (P = 0.001) reduced with the increase in the supplemental levels of emulsifier blends. A positive correlation between emulsifier content in the diet and BWG, DM and fat digestibility, and breast muscle color indices, were also observed. In conclusion, emulsifier blend supplementation positively influenced growth performance and nutrient digestibility in broiler chickens.
Asunto(s)
Pollos/crecimiento & desarrollo , Emulsionantes/metabolismo , Lípidos/sangre , Carne/análisis , Polisorbatos/metabolismo , Estearatos/metabolismo , Alimentación Animal/análisis , Animales , Pollos/sangre , Pollos/fisiología , Dieta/veterinaria , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Emulsionantes/administración & dosificación , Masculino , Polisorbatos/administración & dosificación , Distribución Aleatoria , Estearatos/administración & dosificaciónRESUMEN
Consumption of trans-unsaturated fatty acids promotes atherosclerosis, but whether degradation of fats in macrophages is altered by trans-unsaturated fatty acids is unknown. We compared the metabolism of oleate (C18:1Δ9-10 cis; (Z)-octadec-9-enoate), elaidate (C18:Δ9-10 trans; (E)-octadec-9-enoate), and stearate (C18:0, octadecanoate) in adherent peripheral human macrophages. Metabolism was followed by measurement of acylcarnitines in cell supernatants by MS/MS, determination of cellular fatty acid content by GC/MS, and assessment of ß-oxidation rates using radiolabeled fatty acids. Cells incubated for 44 h in 100 µM elaidate accumulated more unsaturated fatty acids, including both longer- and shorter-chain, and had reduced C18:0 relative to those incubated with oleate or stearate. Both C12:1 and C18:1 acylcarnitines accumulated in supernatants of macrophages exposed to trans fats. These results suggested ß-oxidation inhibition one reaction proximal to the trans bond. Comparison of [1-(14)C]oleate to [1-(14)C]elaidate catabolism showed that elaidate completed the first round of fatty acid ß-oxidation at rates comparable to oleate. Yet, in competitive ß-oxidation assays with [9,10-(3)H]oleate, tritium release rate decreased when unlabeled oleate was replaced by the same quantity of elaidate. These data show specific inhibition of monoenoic fat catabolism by elaidate that is not shared by other atherogenic fats.
Asunto(s)
Macrófagos/metabolismo , Ácido Oléico/farmacología , Carnitina/análogos & derivados , Carnitina/análisis , Carnitina/metabolismo , Células Cultivadas , Ácidos Grasos/análisis , Ácidos Grasos/química , Ácidos Grasos/farmacología , Humanos , Macrófagos/efectos de los fármacos , Ácido Oléico/química , Ácido Oléico/metabolismo , Ácidos Oléicos , Oxidación-Reducción/efectos de los fármacos , Aceites de Plantas/farmacología , Estearatos/metabolismo , Estearatos/farmacología , Espectrometría de Masas en TándemRESUMEN
Palm stearin (PS) and rice bran oil (RBO) blends of varying proportions were subjected to enzymatic interesterification (EIE) using a 1,3 specific immobilized lipase. The interesterified blends were evaluated for their physicochemical characteristics and bioactive phytochemical contents using differential scanning calorimeter (DSC), X-ray diffraction (XRD), gas chromatography (GC) and high performance liquid chromatography (HPLC). The blends of PS and RBO in different proportions (40:60, 50:50, 60:40 and 70:30) had saturated fatty acid content and unsaturated fatty acid content in the range of 37.6-52.0% and 48.0-62.4%, respectively. The blends 40:60, 50:50 and 60:40 showed a considerable reduction in their highest melt peak temperature (TP) and solid fat content (SFC) on EIE. The interesterified blends retained bioactive phytochemicals like tocols (839-1172 ppm), sterols (4318-9647 ppm), oryzanols (3000-6800ppm) and carotene (121-180 ppm). XRD studies demonstrated that the interesterified blends contained beta and beta' polymorphic forms.
Asunto(s)
Arecaceae/metabolismo , Productos Biológicos/metabolismo , Grasas Insaturadas en la Dieta/síntesis química , Hongos/enzimología , Lipasa/metabolismo , Aceites de Plantas/metabolismo , Estearatos/metabolismo , Calorimetría , Carotenoides/metabolismo , Catálisis , Cristalización , Esterificación , Yodo , Fenilpropionatos/metabolismo , Fitosteroles/metabolismo , Aceite de Salvado de Arroz , TemperaturaRESUMEN
The double bond in anaerobic unsaturated fatty acid (UFA) biosynthesis is introduced by the FabA dehydratase/isomerase of the bacterial type II fatty acid biosynthetic pathway. A DeltafabA mutant of Pseudomonas aeruginosa grew aerobically, but required a UFA supplement for anaerobic growth. Wild-type cells produced 18:1Delta11 as the principal UFA, whereas the DeltafabA strain produced only 16:1Delta9. The double bond in the 16:1Delta9 was introduced after phospholipid formation and was localized in the sn-2 position. Two predicted membrane proteins, DesA and DesB, possessed the conserved histidine clusters characteristic of fatty acid desaturases. The DeltafabADeltadesA double mutant required exogenous fatty acids for growth but the DeltafabAdesB double mutant did not. Exogenous stearate was converted to 18:1Delta9 and supported the growth of DeltafabADeltadesA double mutant. A DeltafabADeltadesAdesB triple mutant was unable to desaturate exogenous stearate and was an UFA auxotroph. We detected a 2.5-fold increase in desA expression in DeltafabA mutants, whereas desB expression was derepressed by the deletion of the gene encoding a transcriptional repressor DesT. These data add two aerobic desaturases to the enzymes used for fatty acid metabolism in proteobacteria: DesA, a 2-position phospholipid Delta9-desaturase that supplements the anaerobic FabA pathway, and DesB, an inducible acyl-CoA Delta9-desaturase whose expression is repressed by DesT.
Asunto(s)
Ácidos Grasos Insaturados/biosíntesis , Proteínas de la Membrana/metabolismo , Pseudomonas aeruginosa/enzimología , Estearoil-CoA Desaturasa/metabolismo , Aerobiosis/genética , Secuencia de Aminoácidos , Membrana Celular/enzimología , Ácidos Grasos Insaturados/genética , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Hidroliasas/genética , Proteínas de la Membrana/genética , Datos de Secuencia Molecular , Familia de Multigenes , Pseudomonas aeruginosa/genética , Estearatos/metabolismo , Estearoil-CoA Desaturasa/genética , Especificidad por SustratoRESUMEN
Molecular methods were used to characterize stearate- and heptadecanoate-degrading methanogenic consortia enriched from a low-temperature biodegraded oil field. Stearate- and heptadecanoate-degrading cultures formed acetate. Growth on heptadecanoate was also accompanied by the production of propionate. These fermentation products were transiently accumulated at the beginning of the exponential phase and were further consumed with the concomitant production of methane. Clone libraries of bacterial and archaeal 16S rRNA genes were generated for each stable enrichment. Our 16S rRNA gene-cloning analysis combined with fluorescence in situ hybridization revealed that the predominant microorganisms in the associations were affiliated with a clone cluster close to the genus Syntrophus in the class "Deltaproteobacteria" and with the methanogenic genera Methanocalculus and Methanosaeta. Confocal scanning laser microscopy showed that the bacterial and archaeal cells formed compact aggregates around the insoluble substrates. No layered structure was observed in the aggregate organization. This study reports the presence of new fatty-acid-degrading syntrophic consortia in oil fields and our results suggest that such associations may have an important ecological role in oil fields under methanogenic conditions.
Asunto(s)
Deltaproteobacteria/clasificación , Euryarchaeota/clasificación , Ácidos Grasos/metabolismo , Petróleo/microbiología , Microbiología del Suelo , Estearatos/metabolismo , Ácido Acético/metabolismo , Biodegradación Ambiental , ADN de Archaea/química , ADN de Archaea/genética , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Deltaproteobacteria/citología , Deltaproteobacteria/genética , Deltaproteobacteria/aislamiento & purificación , Deltaproteobacteria/metabolismo , Ecosistema , Euryarchaeota/citología , Euryarchaeota/genética , Euryarchaeota/aislamiento & purificación , Euryarchaeota/metabolismo , Hibridación Fluorescente in Situ , Metano/metabolismo , Methanomicrobiales/clasificación , Methanomicrobiales/citología , Methanomicrobiales/genética , Methanomicrobiales/aislamiento & purificación , Methanomicrobiales/metabolismo , Methanosarcinales/clasificación , Methanosarcinales/citología , Methanosarcinales/genética , Methanosarcinales/aislamiento & purificación , Methanosarcinales/metabolismo , Microscopía Confocal , Datos de Secuencia Molecular , Filogenia , Propionatos/metabolismo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADNRESUMEN
The fatty acid composition of marmoset monkey perirenal fat was examined after long-term feeding of different lipid supplemented diets. Saturated fatty acid supplementation significantly reduced linoleic acid; n-6 polyunsaturated fatty acid (PUFA) supplementation decreased oleic acid but did not reduce the saturated fatty acid content of perirenal fat. Dietary supplementation with fish oil also reduced the level of linoleic acid but increased the level of palmitic acid as well as that of the long-chain n-3 PUFAs. Perirenal fat levels of linoleic acid and docosahexaenoic acid are reliable measures of n-6 and n-3 PUFA intake respectively, but the levels of saturated fatty acids palmitic and stearic do not accurately reflect the marmosets dietary intake.
Asunto(s)
Tejido Adiposo/metabolismo , Callithrix/metabolismo , Dieta , Grasas de la Dieta/farmacología , Ácidos Grasos/metabolismo , Tejido Adiposo/efectos de los fármacos , Animales , Ácidos Grasos Omega-3/metabolismo , Aceites de Pescado , Ácido Linoleico , Ácidos Linoleicos/metabolismo , Masculino , Ácido Palmítico , Ácidos Palmíticos/metabolismo , Estearatos/metabolismoRESUMEN
Molecular gene transfer techniques have been used to engineer the fatty acid composition of Brassica rapa and Brassica napus (canola) oil. Stearoyl-acyl carrier protein (stearoyl-ACP) desaturase (EC 1.14.99.6) catalyzes the first desaturation step in seed oil biosynthesis, converting stearoyl-ACP to oleoyl-ACP. Seed-specific antisense gene constructs of B. rapa stearoyl-ACP desaturase were used to reduce the protein concentration and enzyme activity of stearoyl-ACP desaturase in developing rapeseed embryos during storage lipid biosynthesis. The resulting transgenic plants showed dramatically increased stearate levels in the seeds. A continuous distribution of stearate levels from 2% to 40% was observed in seeds of a transgenic B. napus plant, illustrating the potential to engineer specialized seed oil compositions.
Asunto(s)
Brassica/genética , Oxigenasas de Función Mixta/genética , Aceites de Plantas/metabolismo , Secuencia de Bases , Brassica/crecimiento & desarrollo , Clonación Molecular , ADN/genética , Expresión Génica , Ingeniería Genética , Kanamicina/farmacología , Oxigenasas de Función Mixta/metabolismo , Datos de Secuencia Molecular , ARN sin Sentido , ARN Mensajero/genética , Estearatos/metabolismoRESUMEN
In 32 patients neurological and radiological studies were done after spinal myelography using 5 ml of monoidostearate. The route and speed of elimination of the contrast medium remaining intrathecally have been observed over 2 years, establishing correlations with the way and conditions of administration. In the case of active lumbar drainage from the puncture channel after lumbar instillation of contrast medium or after lumbar puncture, a quick and sometimes massive extrathecal and extravertebral leakage, reaching 1/3 of the applied contrast medium, has been observed in 80%-90% of the cases during the first days and weeks. During the first year, the mean contrast medium elimination was 50%. In the case of a single cisternal instillation of contrast medium, no leakage was found, the elimination was 0-8-1-0 ml/year. The importance of "lumbar puncture drainage" becomes evident, as well as its activity which lasts up to 19 days. The possible routes of leakage (migration) of the contrast medium are discussed.