765 resultados para Fatty acid methyl ester (FAME)


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The cyanobacterium Microcystis aeruginosa strain NPCD-1, isolated from sewage treatment plant and characterized as a non-microcystin producer by mass spectrometry and molecular analysis, was found to be a source of lipid when cultivated in ASM-1 medium at 25 degrees C under constant white fluorescent illumination (109 mu mol photon m(-2) s(-1)). In these conditions, biomass productivity of 46.92 +/- 3.84 mg L-1 day(-1) and lipid content of 28.10 +/- 1.47% were obtained. Quantitative analysis of fatty acid methyl esters demonstrated high concentration of saturated fatty acids (50%), palmitic (24.34%) and lauric (13.21%) acids being the major components. The remaining 50% constituting unsaturated fatty acids showed higher concentrations of oleic (26.88%) and linoleic (12.53%) acids. The feasibility to produce biodiesel from this cyanobacterial lipid was demonstrated by running enzymatic transesterification reactions catalyzed by Novozym (R) 435 and using palm oil as feedstock control. Batch experiments were carried out using tert-butanol and iso-octane as solvent. Results showed similarity on the main ethyl esters formed for both feedstocks. The highest ethyl ester concentration was related to palmitate and oleate esters followed by laurate and linoleate esters. However, both reaction rates and ester yields were dependent on the solvent tested. Total ethyl ester concentrations varied in the range of 44.24-67.84 wt%, corresponding to ester yields from 80 to 100%. Iso-octane provided better solubility and miscibility, with ester yield of 98.10% obtained at 48 h for reaction using the cyanobacterium lipid, while full conversion was achieved in 12 h for reaction carried out with palm oil. These results demonstrated that cyanobacterial lipids from M. aeruginosa NPCD-1 have interesting properties for biofuel production. (c) 2012 Elsevier B.V. All rights reserved.

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The objective of this study was to evaluate the effect of lipid and selenium sources in diets for finishing Nellore steers on the fatty acid composition and selenium concentration of the longissimus muscle. Fifty Nellore steers (body weight = 458 +/- 39 kg) were assigned to one of six dietary treatments: 1) diet containing sunflower seed and inorganic selenium; 2) sunflower seed and organic selenium; 3) whole cottonseed and inorganic selenium; 4) whole cottonseed and organic selenium; 5) soybeans and inorganic selenium; and 6) soybeans and organic selenium. Diets were formulated with the same amount of nitrogen and calories and supplied once daily to steers in collective pens, with three animals per pen, for 120 d. At the end of the trial, steers were slaughtered and samples of the longissimus muscle were collected for fatty acid and selenium analysis. Effect of selenium sources was detected for selenium concentration in the longissimus muscle. Organic selenium had higher concentrations in the meat compared with inorganic selenium. The total saturated, monounsaturated and polyunsaturated fatty acids did not differ between the sources of lipids and selenium. For selenium sources, no differences were observed between the concentrations of polyunsaturated fat. Also, no differences in C18:2 cis-9 trans-11 concentrations were noted; however, steers fed sunflower seed presented greater proportions of this fatty acid in the meat. The results indicated that the use of sunflower seed, cottonseed or soybeans and organic or inorganic selenium in feedlot diets to Nellore cattle does not alter the great part of the fatty acid profile of the longissimus muscle. However, the inclusion of sunflower seed in the diet increases the meat CLA cis-9, trans-11, which is desirable and beneficial for the health of consumers.

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Smoking crack cocaine involves the inhalation of cocaine and its pyrolysis product, anhydroecgonine methyl ester (AEME). Although there is evidence that cocaine is neurotoxic, the neurotoxicity of AEME has never been evaluated. AEME seems to have cholinergic agonist properties in the cardiovascular system; however, there are no reports on its effects in the central nervous system. The aim of this study was to investigate the neurotoxicity of AEME and its possible cholinergic effects in rat primary hippocampal cell cultures that were exposed to different concentrations of AEME, cocaine, and a cocaineAEME combination. We also evaluated the involvement of muscarinic cholinergic receptors in the neuronal death induced by these treatments using concomitant incubation of the cells with atropine. Neuronal injury was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. The results of the viability assays showed that AEME is a neurotoxic agent that has greater neurotoxic potential than cocaine after 24 and 48 h of exposure. We also showed that incubation for 48 h with a combination of both compounds in equipotent concentrations had an additive neurotoxic effect. Although both substances decreased cell viability in the MTT assay, only cocaine increased LDH release. Caspase-3 activity was increased after 3 and 6 h of incubation with 1mM cocaine and after 6 h of 0.1 and 1.0mM AEME exposure. Atropine prevented the AEME-induced neurotoxicity, which suggests that muscarinic cholinergic receptors are involved in AEME's effects. In addition, binding experiments confirmed that AEME has an affinity for muscarinic cholinergic receptors. Nevertheless, atropine was not able to prevent the neurotoxicity produced by cocaine and the cocaineAEME combination, suggesting that these treatments activated other neuronal death pathways. Our results suggest a higher risk for neurotoxicity after smoking crack cocaine than after cocaine use alone.

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The objective of this study was to evaluate the fatty acid composition of the longissimus dorsi muscle in carcasses of 3/4 Bos taurus taurus 1/4 Bos taurus indicus steers fed different sources of fatty acids. Thirty-six steers aged 14 months, with a mean live weight of 320 kg, were fed the following diets for 96 days:1) control diet, containing no supplemental fat source; 2) CaSFA, diet containing 50 g calcium salts of fatty acids per kg total dry matter; 3) CS diet, containing 210 g cottonseed per kg total dry matter. The fatty acid composition of the longissimus dorsi muscle was determined by gas chromatography. No difference in slaughter weight, carcass weight, backfat thickness, or longissimus dorsi muscle area was observed between animals receiving the diets CaSFA and CS. Animals consuming the two fat-supplemented diets presented higher concentrations of oleic (C18:1), palmitic (C16:0) and stearic (C18:0) acids, corresponding to an average 80.76% of total fatty acids, and higher concentrations of vaccenic acid (C18:1 t11) in the muscle when compared with the control group. Supplementation of the diet of feedlot crossbred steers with CaSFA or cottonseed did not promote significant alterations in the lipid composition of the longissimus dorsi muscle.

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Development of dairy organic probiotic fermented products is of great interest as they associate ecological practices and benefits of probiotic bacteria. As organic management practices of cow milk production allow modification of the fatty acid composition of milk (as compared to conventional milk), we studied the influence of the type of milk on some characteristics of fermented milks, such as acidification kinetics. bacterial counts and fatty acid content. Conventional and organic probiotic fermented milks were produced using Bifidobacterium animalis subsp. lactis HN019 in co-culture with Streptococcus thermophilus TA040 and Lactobacillus delbrueckii subsp. bulgaricus LB340. The use of organic milk led to a higher acidification rate and cultivability of Lactobacillus bulgaricus. Fatty acids profile of organic fermented milks showed higher amounts of trans-octadecenoic acid (C18:1, 1.6 times) and polyunsaturated fatty acids, including cis-9 trans-11. C18:2 conjugated linoleic (CLA-1.4 times), and alpha-linolenic acids (ALA-1.6 times), as compared to conventional fermented milks. These higher levels were the result of both initial percentage in the milk and increase during acidification, with no further modification during storage. Finally, use of bifidobacteria slightly increased CLA relative content in the conventional fermented milks, after 7 days of storage at 4 degrees C, whereas no difference was seen in organic fermented milks. (C) 2012 Elsevier Ltd. All rights reserved.

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Credneramides A (1) and B (2), two vinyl chloride-containing metabolites, were isolated from a Papua New Guinea collection of cf. Trichodesmium sp. nov. and expand a recently described class of vinyl chloride-containing natural products. The precursor fatty acid, credneric acid (3), was isolated from both the aqueous and organic fractions of the parent fraction as well as from another geographically and phylogenetically distinct cyanobacterial collection (Panama). Credneramides A and B inhibited spontaneous calcium oscillations in murine cerebrocortical neurons at low micro-molar concentrations (1, IC50 4.0 mu M; 2, IC50 3.8 mu M).

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High saturated and trans fatty acid intake, the typical dietary pattern of Western populations, favors a proinflammatory status that contributes to generating insulin resistance (IR). We examined whether the consumption of these fatty acids was associated with IR and inflammatory markers. In this cross-sectional study, 127 non-diabetic individuals were allocated to a group without IR and 56 to another with IR, defined as homeostasis model assessment-IR (HOMA-IR) >2.71. Diet was assessed using 24-h food recalls. Multiple linear regression was employed to test independent associations with HOMA-IR. The IR group presented worse anthropometric, biochemical and inflammatory profiles. Energy intake was correlated with abdominal circumference and inversely with adiponectin concentrations (r = -0.227, P = 0.002), while saturated fat intake correlated with inflammatory markers and trans fat with HOMA-IR (r = 0.160, P = 0.030). Abdominal circumference was associated with HOMA-IR (r = 0.430, P < 0.001). In multiple analysis, HOMA-IR remained associated with trans fat intake (beta = 1.416, P = 0.039) and body mass index (beta = 0.390, P < 0.001), and was also inversely associated with adiponectin (beta = -1.637, P = 0.004). Inclusion of other nutrients (saturated fat and added sugar) or other inflammatory markers (IL-6 and CRP) into the models did not modify these associations. Our study supports that trans fat intake impairs insulin sensitivity. The hypothesis that its effect could depend on transcription factors, resulting in expression of proinflammatory genes, was not corroborated. We speculate that trans fat interferes predominantly with insulin signaling via intracellular kinases, which alter insulin receptor substrates.

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BACKGROUND/OBJECTIVES: To assess the performance of a food frequency questionnaire (FFQ) for estimating omega-3, omega-6 and trans fatty acid intake during pregnancy. Moreover, we determined whether the fatty acid composition of mature breast milk represents a valuable biomarker for fatty acid intake during pregnancy. SUBJECTS/METHODS: A prospective study in 41 pregnant women, aged 18-35 years, was conducted. Food intake during pregnancy was evaluated by three 24-h recalls (24 hR), and 2 FFQ. The fatty acid composition of mature breast milk was determined by gas chromatography. The method of triads and joint classification between quartiles of intake were applied. RESULTS: The FFQ was accurate for estimating docosahexanoic (DHA), linoleic and total omega-6 fatty acids according to validity coefficients. Higher agreements (>70%) into the same or adjacent quartiles between the dietary methods were found for alpha-linolenic, total omega-3, linoleic and trans fatty acid intake. High validity coefficients for eicosapentanoic (EPA) and DHA acids of human milk were found (0.61 and 0.73, respectively), and the method was adequate for categorizing the intake of alpha-linolenic, total omega-3 and trans fatty acids compared with FFQ estimates, and for arachidonic acid and trans fatty acids compared with food recall estimates, during pregnancy. CONCLUSIONS: The FFQ was an accurate tool for categorizing alpha-linolenic, total omega-3 and trans fatty acid intake. According to the validity coefficients observed, the FFQ accurately estimated DHA, linoleic and total omega-6 fatty acids and the composition of mature breast milk was shown to be a suitable biomarker for EPA and DHA fatty acid intake during pregnancy.

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A low-protein, high-carbohydrate (LPHC) diet for 15 days increased the lipid content in the carcass and adipose tissues of rats. The aim of this work was to investigate the mechanisms of this lipid increase in the retroperitoneal white adipose tissue (RWAT) of these animals. The LPHC diet induced an approximately two- and tenfold increase in serum corticosterone and TNF-alpha, respectively. The rate of de novo fatty acid (FA) synthesis in vivo was reduced (50%) in LPHC rats, and the lipoprotein lipase activity increased (100%). In addition, glycerokinase activity increased (60%), and the phosphoenolpyruvate carboxykinase content decreased (27%). Basal [U-C-14]-glucose incorporation into glycerol-triacylglycerol did not differ between the groups; however, in the presence of insulin, [U-C-14]-glucose incorporation increased by 124% in adipocytes from only control rats. The reductions in IRS1 and AKT content as well as AKT phosphorylation in the RWAT from LPHC rats and the absence of an insulin response suggest that these adipocytes have reduced insulin sensitivity. The increase in NE turnover by 45% and the lack of a lipolytic response to NE in adipocytes from LPHC rats imply catecholamine resistance. The data reveal that the increase in fat storage in the RWAT of LPHC rats results from an increase in FA uptake from circulating lipoproteins and glycerol phosphorylation, which is accompanied by an impaired lipolysis that is activated by NE.

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This study evaluated the effect of the supplementation of total dietary fiber from apple, banana or passion fruit processing by-products on the post-acidification, total titratable acidity, bacteria counts and fatty acid profiles in skim milk yoghurts co-fermented by four different probiotics strains: Lactobacillus acidophilus L10 and Bifidobacterium animalis subsp. lactis BL04, HN019 and B94. Apple and banana fibers increased the probiotic viability during shelf-life. All the fibers were able to increase the short chain and polyunsaturated fatty acid contents of yoghurts compared to their respective controls. A synergistic effect between the type of fiber and the probiotic strain on the conjugated linoleic acid content was observed, and the amount of alpha-linolenic acid was increased by banana fiber. The results of this study demonstrate, for the first time, that fruit fibers can improve the fatty acid profile of probiotic yoghurts and point out the suitability of using fibers from fruit processing the by-products to develop new high value-added fermented dairy products. (C) 2012 Elsevier By. All rights reserved.

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The impact of tannery sludge application on soil microbial community and diversity is poorly understood. We studied the microbial community in an agricultural soil following two applications (2006 and 2007) of tannery sludge with annual application rates of 0.0,2.3 and 22.6 Mg ha(-1). The soil was sampled 12 and 271 days after the second (2007) application. Community structure was assessed via a phospholipid fatty acid analysis, and the physiological profile of the soil microbial community via the Biolog method. Tannery sludge application changed soil chemical properties, increasing the soil pH and electrical conductivity as well as available P and mineral N concentrations. The higher sludge application rate changed the community structure and the physiological profile of the microbial community at both sampling dates. However, there is no clear link between community structure and carbon substrate utilization. According to the Distance Based Linear Models Analysis, the fatty acids 16:0 and 117:0 together contributed 84% to the observed PLFA patterns, whereas the chemical properties available P, mineral N, and Ca, and pH together contributed 54%. At 12 days, tannery sludge application increased the average well color development from 0.46 to 0.87 after 48 h, and reduced the time elapsed before reaching the midpoint carbon substrate utilization (s) from 71 to 44 h, an effect still apparent nine months after application of the higher sludge application rate. The dominant signature fatty acids and kinetic parameters (r and s) were correlated to the concentrations of available P. Ca, mineral N, pH and EC. (c) 2012 Elsevier B.V. All rights reserved.

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Objective. The aim of this study was to investigate the effect of CAPE on the insulin signaling and inflammatory pathway in the liver of mice with high fat diet induced obesity. Material/Methods. Swiss mice were fed with standard chow or high-fat diet for 12-week. After the eighth week, animals in the HFD group with serum glucose levels higher than 200 mg/dL were divided into two groups, HFD and HFD receiving 30 mg/kg of CAPE for 4 weeks. After 12 weeks, the blood samples could be collected and liver tissue extracted for hormonal and biochemical measurements, and insulin signaling and inflammatory pathway analyzes. Results. The high-fat diet group exhibited more weight gain, glucose intolerance, and hepatic steatosis compared with standard diet group. The CAPE treatment showed improvement in glucose sensitivity characterized by an area under glucose curve similar to the control group in an oral glucose tolerance test Furthermore, CAPE treatment promoted amelioration in hepatic steatosis compared with the high-fat diet group. The increase in glucose sensitivity was associated with the improvement in insulin-stimulated phosphorylation of the insulin receptor substrate-2, followed by an increase in Akt phosphorylation. In addition, it was observed that CAPE reduced the induction of the inflammatory pathway, c-jun-N- terminal kinase, the nuclear factor kappa B, and cyclooxygenase-2 expression, respectively. Conclusions. Overall, these findings indicate that CAPE exhibited anti-inflammatory activity that partly restores normal metabolism, reduces the molecular changes observed in obesity and insulin resistance, and therefore has a potential as a therapeutic agent in obesity. (C) 2012 Elsevier Inc. All rights reserved.

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The aim of this study was to determine and compare the fatty acid (FA) composition of colostrum and mature milk produced by nursing mothers of preterm and at-term newborns, in Florianopolis, SC, Brazil. Low contents of Eicosapentaenoic acid (EPA) (0.02%/colostrum and 0.01%/mature milk for preterm and term milk) and Docosahexaenoic acid (DHA) (colostrum group: 0.10%/preterm and 0.09%/term; mature milk: 0.05%/preterm and 0.03%/term) were determined. The comparison among the groups showed that the elaidic acid content was significantly higher (1.67%) in mature term milk. The content of rumenic acid (conjugated linoleic acid) was significantly higher in at-term colostrum compared with preterm colostrum. When considering the maturity of the milk, there was a significant increase in the percentage of this FA in the preterm group. The results show that, overall, the greatest differences observed were between the colostrums and mature milks for both groups and not between preterm and at-term mothers.

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Rainbow trout Oncorhynchus mykiss triploids are regularly produced in fish farms to improve growth because the triploid females do not develop ovaries during the reproductive cycle. In this study, the tissue fatty acid allocations in triploid and diploid females were compared during the reproductive cycle to determine whether the ploidy influences the fatty acid profile of fish produced in aquaculture. The ovaries, liver, and white muscle fatty acid contents of diploid and triploid females were analyzed during the reproductive cycle. Diploid females tend to accumulate more polyunsaturated fatty acids than triploids during some phases of the reproductive cycle, and this profile was compensated by an increase in saturated and monounsaturated fatty acids in triploid females. Arachidonic acid (C20:4n6) was the main n6 polyunsaturated fatty acid in the ovaries of diploid females during the most advanced phases of the reproductive cycle, and docosahexaenoic acid (C22:6n3) was the main n3 polyunsaturated fatty acid. In triploid females, the percentage of both of these polyunsaturated fatty acids was lower than in diploid females during the most advanced phases of the reproductive cycle. In general, the lack of ovary development altered the hepatic synthesis of some fatty acids, mainly monounsaturated and polyunsaturated fatty acids, decreasing the content of the main fatty acids in the white muscle and, consequently, the mobilization of these specific fatty acids to the ovaries.

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In addition to the strong influence of the broodstock diet on the development and survival of offspring, domestication may also interfere with the larval life success. We obtained eggs from wild and domesticated Salminus hilarii females and domesticated males. Wild females were caught in the Tiete River and tributaries, and the domesticated females were born three years before the beginning of the experiment in the Ponte Nova Fish Farm. Animals from both groups were fed with the same feed to exclude feed variables. The eggs and larvae were sampled at 0, 8, 16, and 28 h after spawning (HAS), with the last sampling (28 HAS) coinciding with hatching time. After hatching, samplings proceeded at 32, 48, 66, and 96 HAS, with the last sampling (96 HAS) corresponding to the end of yolk sac consumption. Finally, the last experimental period was during the larvae exogenous feeding phase, at 102, 118, 166, and 214 HAS. Our data revealed that domestication of S. hilarii females influenced fatty acid (FA) metabolism during embryo and larva development. However, the structure of membrane phospholipid FA remained mostly stable, with changes principally in the neutral fraction. When the external conditions, mainly water and feed quality, remained constant, domestication of S. hilarii females did not significantly affect the structural FA composition but influenced the selectivity of consumption and/or storage of specific FA.