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This paper presents the results of a study whose aim was to test the effects of several doses of pectin and phytosterols on the sterol content in plasma, liver and feces of guinea pigs, when added to a high‐saturated fat diet. The treatments followed a 3×3 factorial design, with three levels of pectin (0, 3.67 and 6.93%) and three levels of phytosterols (0, 1.37 and 2.45%). Seventy‐two female Dunkin Hartley guinea pigs were randomly assigned to the treatment groups (eight animals per group). The duration of the treatment was 4 weeks. No differences were found in plasma cholesterol concentrations, while in liver we saw a reduction in cholesterol concentration after phytosterol feeding. Moreover, we found no pectin effects. Plant sterol concentration increased in plasma and liver after phytosterol ingestion, with the highest concentrations being obtained with the intermediate pectin dose. Our results suggest that a high‐saturated diet may impair the cholesterol‐lowering properties of plant sterols and pectin.  相似文献   

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This study evaluated the effects of a ketogenic diet (KD) based on extra virgin coconut oil (Cocos nucifera L., VCO), on the treatment of epileptic rats. Two sets of experiments were conducted. First, male Wistar rats underwent induction of status epilepticus (SE) with the administration of pilocarpine intraperitoneally 21 animals reached spontaneous recurrent seizures (SRS) and were randomly allocated to the dietary regimens and video‐monitored for 19 days. In the second experiment, 24 animals were randomized immediately after the induction of SE and followed for 67 days. Diets were as follows: Control (AIN‐93G; 7% lipid), KetoTAGsoya (KD based on soybean oil; 69.79% lipid), and KetoTAGcoco (KD based on VCO; 69.79% lipid). There were no differences in the latency to the first crisis, total frequency, and duration of the SRS between groups in 2 experiments. The data suggest no effects of KD, with or without VCO, in rats with pilocarpine‐induced epilepsy.  相似文献   

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Changes in dietary composition will have a significant impact on the nutritional status of the mother and the offspring. To examine the relevant hormone level changes during lactation and the expression of fatty acid transporters in the placenta and liver under the condition of a high‐fat (HF) diet, we established HF animal models and conducted a cross‐fostering program to mimic the shift in diet. On gestation day (GD)18, the weight of placenta in the HF group was significantly higher than that in the control group (p < 0.05). HF‐fed male pups had a significantly lower serum insulin level, but the same phenomenon was not found in females. On the contrary, serum triacylglycerol (TAG) level presented a tendency to decrease only in female offspring. Oil red O staining showed lipid accumulation in the HF diet offspring livers. The mRNA levels of FATP4 in the placenta in the HF diet group were significantly upregulated compared to the control diet group (p < 0.05). High‐fat diet (HFD) consumption also altered the liver mRNA levels of FATP4, SREBP‐1, and SCD‐1 in the male offspring, while the changes in protein levels of FATP4 were not observed in either sex. In conclusion, maternal HF diet has a profound impact on offspring growth, metabolism, and the risk of metabolic disorders, which would depend on the exposure period of pregnancy and lactation.  相似文献   

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CLA has been reported to have beneficial and controversial effects on glucose and lipid metabolism. Besides, high fat (HF) diets induce alterations in liver and muscle lipid deposition, which could be associated with anomalous glucose utilization. Therefore, our aim was to evaluate whether the intake of CLA could prevent alterations in glycolytic intermediate metabolites and glycogen deposition induced by a HF diet. For this purpose, growing mice were fed a control diet (7% corn oil), a HF diet (20% corn oil), or a HF diet containing 17% corn oil + 3% CLA for 30 days. Liver and muscle glucose intermediate metabolites and glycogen were assessed. Liver glycolysis was inhibited by HF, reflected by a decreased flow of substrates through phosphofructokinase‐1α linked to elevated citrate. CLA at HF diet prevented these alterations while increasing the lactate and glycogen synthesis. In the muscle, the HF diet emphasized the reduction of the flux through phosphofructokinase‐1α, without additional changes in total glycogen levels. In conclusion, dietary CLA partially prevented glycolytic pathway alterations in the liver but not in the muscle of mice fed a HF diet, associated with adverse effects as sustained hyperglycemia and hepatic lactate accumulation. Practical applications: The present study evaluates the potential use of CLA and its consequences on several aspects of glucose metabolism. Considering that the FDA has recently approved CLA as a Generally Recognized as Safe (GRAS) category, a measure that will foster the commercial production of food and beverages with CLA supplementation, we believe it is relevant to study its potential functional properties on glucose metabolism in an experimental animal model characterized by alterations in liver and muscle lipid deposition.  相似文献   

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The objective of this research was to evaluate the effect of high‐intensity ultrasound (HIU) and crystallization temperature (Tc) on the crystallization behavior, melting profile, and elasticity of a soft stearin fraction of high‐stearic high‐oleic sunflower oil. Results showed that HIU can be used to induce and increase the rate of crystallization of the soft stearin with significantly higher SFC values obtained in the sonicated samples, especially at higher Tc. SFC values were fitted using the Avrami model, and higher kn and lower n values were obtained when samples were crystallized with sonication, suggesting that sonicated samples crystallized faster and through an instantaneous nucleation mechanism. In addition, the crystal morphology, melting behavior, and viscoelasticity were significantly affected by sonication.  相似文献   

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Formation of a low‐fat oil‐in‐water (O/W) nanoemulsion enriched with vitamin E using the nonionic surfactant Tween 40 is studied by means of a high‐pressure homogenizer. The effect of different process variables of the emulsification process, including pressure, temperature, and concentration of the emulsifying agent, is evaluated. The relation between pressure and the obtained mean droplet diameter is derived and described by an equation which can be taken as a basis of any process design. The droplet size can be decreased by increasing the vitamin E concentration. A higher fat content slightly affects the droplet size distribution and the mean droplet diameter of the nanoemulsion, so it is recommended to use preparations of nanoemulsions with low fat contents enriched with vitamin E for dietary supplement.  相似文献   

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The objective of this study was to evaluate the beneficial effect of α‐linolenic acid‐rich black raspberry seed (BRS) oil on lipid metabolism in high‐fat diet (HFD)‐induced obese and db/db mice. Five‐week‐old C57BL/6 mice were fed diets consisting of 50% calories from lard, 5% from soybean, and 5% from corn oil (HFD), or 50% calories from lard and 10% from BRS oil (HFD + BRS oil diet) for 12 weeks. Six‐week‐old C57BL/KsJ‐db/db mice were fed diets consisting of 16% calories from soybean oil (standard diet), 8% from soybean, and 8% from BRS oil, or 16% from BRS oil for 10 weeks. The BRS oil diets lowered the levels of triacylglycerol, nonesterified fatty acids, and total cholesterol in serum and liver of both of the obese and db/db mice as compared with the HFD and standard diet, respectively. mRNA levels of lipogenesis markers including cluster of differentiation 36, fatty‐acid‐binding protein 1, sterol regulatory element binding protein 1c, fatty‐acid synthase, and solute carrier family 25 member 1 in the liver of the BRS oil groups were lower than those in the liver of the HFD and standard groups in the obese and db/db mice, respectively. On the other hand, fatty‐acid oxidation markers including carnitine palmitoyltransferase 1A, acyl‐CoA dehydrogenase, hydroxylacyl‐CoA dehydrogenase α, and acyl‐CoA oxidase in the liver of the BRS oil groups were higher than those in the liver of the HFD and standard groups in the obese and db/db mice, respectively. Peroxisome proliferator‐activated receptor α mRNA and protein levels increased in the liver and epididymal adipose tissue of the obese and db/db mice fed BRS oil compared with HFD and standard diet, respectively. BRS oil might improve lipid metabolism by inhibiting lipogenesis and promoting fatty‐acid oxidation in HFD‐induced obese and db/db mice.  相似文献   

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Deoxygenation is a critical step in making hydrocarbon‐rich biofuels from biomass constituents. Although the thermal effects of oxygenate aromatization have been widely reported, the effect of pressure on this critical reaction has not yet been closely investigated, one primary reason being the unavailability of a reactor that can pyrolyze oxygenates, especially those in solid form, under pressurized conditions. Here, the first of a series of studies on how oxygenates behave when catalytically pyrolyzed under elevated pressure and temperature conditions is reported. Methanol, the simplest alcohol, was selected as the candidate to study the chemical phenomena that occur under pressurized catalytic pyrolysis. The reactions were carried out over the shape‐selective catalyst ZSM‐5 (SiO2/Al2O3 = 30) under varying pressure (0 to 2.0684 MPa (300 psi) in 0.3447 MPa (50 psi) increments) and temperature (500 to 800 °C in 50 °C increments) conditions. Benzene, toluene, ethyl benzene, and xylenes (BTEX) were analyzed as the deoxygenated products of the reaction. The results indicate that the reactor pressure significantly affects deoxygenated product composition.  相似文献   

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Modeling the high‐pressure polymerization of ethene is of vital importance in order to avoid costly high‐pressure experiments when it comes to process optimization and product design. However, closing the heat balance when modeling high‐pressure tubular reactors with a counter‐current jacket cooling is still difficult. In this contribution the influence of thermo‐physical properties – namely viscosity and heat capacity – on the simulation results was investigated. Various literature sources were evaluated and a variety of simulations were conducted, showing that both properties influence the resulting temperature profiles and conversions visibly, while the molecular weight distribution was not affected. Uncertainties of the heat capacity of 5 % could be compensated by varying initiator efficiency and fouling layer thickness within physically reasonable boundaries.  相似文献   

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A maternal high fat diet (HFD) can have adverse effects on skeletal muscle development. Skeletal muscle PLIN proteins (PLIN2, 3 and 5) are thought to play critical roles in lipid metabolism, however effects of HFD on PLIN and lipases (HSL, ATGL, CGI‐58) in mothers as well as their offspring have yet to be investigated. The primary objective of this study was to determine whether maternal HFD would influence skeletal muscle lipase and PLIN protein content in offspring at weaning (19d) and young adulthood (3mo). Female rats (28d old, n = 9/group) were fed control (CON, AIN93G, 7 % soybean oil) or HFD (AIN93G, 20 % lard) for 10 weeks prior to mating and throughout pregnancy and lactation. All offspring were weaned to CON [n = 18/group, 1 female and 1 male pup per litter were studied at weaning (19d) and 3mo of age]. There was no effect of sex for the main outcomes measured in plantaris, therefore male and female data was combined. Maternal HFD resulted in higher triacylglycerol content in pups at 3mo (p < 0.05), as well as in the dams (p = 0.015). Maternal HFD resulted in higher PLIN5 content in pups at weaning and 3mo (p = 0.05). PLIN2 and PLIN5 content decreased at 3mo versus weaning (p < 0.001). HFD dams had a higher PLIN3 content (p = 0.016). Diet had no effect on ATGL, CGI‐58, or HSL content. In conclusion, exposure to a maternal HFD resulted in higher skeletal muscle lipid and PLIN5 content in plantaris of offspring through to young adulthood.  相似文献   

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Polyurethane dispersions (PUDs) have been an active area of research since the early 1940s because of legislative restrictions on the use of organic solvents in conventional solvent‐based products and also because PUDs exhibit almost the same high performance levels as solvent‐borne polyurethanes. In the present study, properties of conventional waterborne PUDs are modified with epoxy‐acrylic graft copolymer blocks. The epoxy‐acrylic graft copolymers were first modified with ethylene diamine to give amine‐terminated blocks which in turn reacted with isocyanate‐terminated prepolymer (prepolymer mixing process) to give modified PUDs. Several experimental sets were prepared with varying compositions. The experimental sets were also prepared using conventional poly(ethylene glycol) blocks and ethylene diamine chain‐extenders. The physico‐chemical properties and film characteristics of the experimental sets show the dramatic improvement in important mechanical properties of PUDs due to grafting with epoxy‐acrylic copolymer blocks. Copyright © 2004 Society of Chemical Industry  相似文献   

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By replacing thermal concentration processes, high‐pressure reverse osmosis has the potential to contribute to cost and energy savings regarding concepts for industrial water reuse. To provide a better understanding of the spiral‐wound element behavior during high‐pressure operation, this study focusses on the investigation of their performance by scrutinizing the crucial effect of the permeate‐sided pressure drop induced by membrane‐spacer interactions. The experiments show a considerable influence of membrane intrusion on the element performance with a strong dependence on the feed pressure.  相似文献   

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The spectral performance, sensitiveness to ignition stimuli and burning rate of bi‐spectral flare formulations based on tetrazole containing fuels, 5‐phenyl‐1H‐tetrazole, 5,5′‐(1,4‐phenylene)bis(1H‐tetrazole) and 5‐(4‐nitro‐phenyl)‐1H‐tetrazole, utilizing potassium perchlorate as the oxidizer, are reported. The formulation based on 5‐(4‐nitro‐phenyl)‐1H‐tetrazole yielded the highest spectral efficiency in the β‐band (44.1 J g−1 sr−1). The formulation based on 5‐phenyl‐1H‐tetrazole gave the highest color ratio (θβ/α=6.8) and was the least sensitive.  相似文献   

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Initial investigations on liquid feed injection in a high density circulating fluidized bed of fluid catalysed cracking (FCC) particles were performed by means of fast responding thermocouples and capacitance probes. The results imply very limited radial mixing between dry solids, wet solids, and liquids for injection parallel to the hot up‐streaming gas‐solid flow.  相似文献   

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