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991.
Interaction between dietary protein and fat in triglyceride metabolism in the rat: Effects of soy protein and menhaden oil 总被引:4,自引:0,他引:4
The objective of the present study was to determine the mechanisms by which dietary proteins interact with dietary lipids
in the regulation of triglyceridemia in rats. Male Sprague-Dawley rats (n=56) were subjected to 28-d experimental diets containing different combinations of proteins (20% w/w) and lipid sources (14%
w/w): (i) casein-menhaden oil, (ii) casein-beef tallow, (iii) soy protein-menhaden oil, and (iv) soy protein-beef tallow.
Significant protein-lipid interactions were observed on triglyceridemia and hepatic cholesterol in fasted rats. The combination
of casein and beef tallow was associated with high plasma TG and hepatic cholesterol concentrations, which were reduced by
substitution either of soy for casein or of menhaden oil for beef tallow. Therefore, triglyceridemia and liver cholesterol
remained low with soy protein feeding, independently of the lipid source, as well as with menhaden oil feeding, regardless
of the protein source. The menhaden oil diets reduced plasma cholesterol, hepatic TG, and TG secretion compared with beef
tallow diets independently of the dietary protein source. Modifying the source of dietary proteins and lipids had no effect
on post-heparin plasma lipoprotein lipase activity. These results demonstrate that soy protein can lower rat triglyceridemia
relative to casein when associated with beef tallow consumption, whereas menhaden oil can attenuate hypertriglyceridemia when
rats are fed casein. The data further suggest that part of the hypotriglyceridemic effect of soy protein in the rat may be
mediated by reduced hepatic lipid synthesis, as is the case for menhaden oil. 相似文献
992.
Raúl Quijada Juan Luis Guevara Mehrdad Yazdani-Pedram Griselda B. Galland Daniel Ribeiro 《Polymer Bulletin》2002,49(4):273-280
Summary
1-Octadecene (C18) was polymerized by using different metallocene catalysts. The rac-Et(Ind)2ZrC12/MAO (I) and rac-Me2Si(Ind)2ZrC12/MAO (III) presented the highest activity as compared with ra-Et(2-Me-Ind)2ZrCl2/MAO (II) and Ph2C(Flu)(Cp)ZrC12/MAO (IV) catalysts. Catalyst IV produced polymers with highest molecular weights. The microstructure of the polymers was
determined by 13C-NMR spectroscopy. Catalyst systems I, II and III produced isotactic polymers while catalyst IV produced polymers with mainly
syndiotactic structures but with large amount of stereoregular error.
Received: 21 June 2002/Revised version: 4 November 2002/ Accepted: 4 November 2002 相似文献
993.
994.
An acid-activated clay (Çanakkale montmorillonite from Turkey) was used to adsorb chlorophyll from hexane solutions. The phenomenon seems to be mainly driven by the interaction of chlorophyll with acid sites. The adsorption of chlorophyll on Brönsted acid sites was indicated by a characteristic infrared band for the -OH group at 3671 cm?1. The variations in the structure of clay mineral and chlorophyll during adsorption have been examined by differential thermal analysis, thermogravimetry and infrared spectroscopy of the activated clay before and after adsorption of chlorophyll. Oxidation of adsorbed chlorophyll was completed at quite a high temperature. 相似文献
995.
The Interaction between Lauric and Stearic Acid and the Ni-NiO Catalyst System The reactivity of the Ni-NiO catalytic system of following degrees of reduction: 0, 35–65 and 100% Ni with the pure chemical quality lauric and stearic acids during the catalyst passivating conditions 75–115°C were followed in the time period 0–100 hours. The quantity of interaction product of nickel salts of fatty acids in the catalyst is controlled both of the initial reactivity of the Ni-NiO system with the fatty acids and of the kinetics of the zero reaction order. Although the lauric acid is expressively more reactive than the stearic acid, the activity of the in this way prepared catalysts tested in hydrogenation of free fatty acids did not show significant differences. 相似文献
996.
Bleaching of Vegetable Oils II.: Kinetics of the Bleaching Process The study deals with the kinetics of bleaching. The test-system used rapeseed oil with a low content of erucic acid and added bleaching earth Tonsil Optimum FF. By means of the results obtained an empiric equation was then developed describing the process taking part under the conditions studied. 相似文献
997.
FA and tocopherol composition of Vietnamese oilseeds 总被引:1,自引:0,他引:1
Bertrand?MatthausEmail author Klaus?Vosmann Long?Quoc?Pham Kurt?Aitzetmüller 《Journal of the American Oil Chemists' Society》2003,80(10):1013-1020
Seeds of 40 oilseed species from 23 different plant families (Brassicaceae, Cucurbitaceae, Fabaceae, Sapindaceae, Malvaceae,
Gnetaceae, Clusiaceae, Bruseraceae, Ranunculaceae, Convolvulaceae, Amaranthaceae, Tiliaceae, Basellaceae, Solanaceae, Umbelliferae,
Labiatae, Compositae, Theaceae, Euphorbiaceae, Caesalpiniaceae, Sapotaceae, Anacardiaceae, and Connaraceae) grown in Vietnam
were analyzed for oilseed oil content, FA, and vitamin E. The seed oil content varied between 0.2 g/100 g for Mangifera indica and 75.7 g/100 g for Calophyllum inophyllum, whereas only nine seeds contained more than 40% oil. The tocopherol content ranged from 26 (Sapindus mukorossi) to 9361 mg/kg (Litchi chinensis). In nine seed oils unusual FA such as conjugated, cyclopropenoic, or epoxy FA were found. 相似文献
998.
Compatibility of acidic (H), Na, and Zn neutralized sulfonated polystyrene ionomer blends with Poly(2,6-dimethyl- 1,4-phenylene
oxide) (PPO) and Poly(2,6-dichloro- 1,4-phenylene oxide) (PDCIPO) was investigated by Dilute Solution Viscometry (DSV) and
Differential Scanning Calorimetry (DSC). The intrinsic viscosities of the blends, are measured in suitable solvents. The degree
of compatibility of the blends is characterized by Δb parameter. According to the results, PPO is completely miscible, except
for Na-neutralized 1.7 mol% sulfonated polystyrene (Na1.7SPS) which is completely immiscible with PPO and PDClPO. PDClPO is
completely miscible with Zn-neutralized sulfonated polystyrene (Zn4.8SPS) and partially miscible with acid sulfonated polystyrene
(4.8SPS).
Received: 12 August 2001/Revised version: 21 January 2002/Accepted: 11 March 2003
Correspondence to Leyla Aras 相似文献
999.
The kinetics of the transition metal-catalysed direct addition of amine NH bonds to carbon--carbon multiple bonds (hydroamination) has been explored by in situ spectroscopic techniques. From an open mass balance it was concluded that an intermediate species was formed during the cyclisation of 6-aminohex-1-yne. This species was identified as the enamine 2-methylene-piperidine, which is the primary hydroamination product. 相似文献
1000.
Cem??zdemir Ayse?Nilgün?Akin Ramazan?YildirimEmail author 《Korean Journal of Chemical Engineering》2003,20(5):840-843
The maximization of the total surface area of Pt-SnO2/Al2O3 catalyst was studied by using the Taguchi method of experimental design. The catalysts were prepared by sol-gel method. The
effects of HNO3, H2O and aluminum nitrate concentrations and the stirring rate on the total surface area were studied at three levels of each.
L9 orthogonal array leading nine experiments was used in the experimental design. The parameter levels that give maximum total
surface area were determined and experimentally verified. In the range of conditions studied it was found that, medium levels
of HNO3 and H2O concentration and lower levels of aluminum nitrate concentration and stirring rate maximize the total surface area. 相似文献