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1.
Oats are a good source of many vitamins and minerals, including compounds that collectively constitute vitamin E, the tocols. Tocols are comprised of two subgroups, tocopherols and tocotrienols. Due to their potent antioxidant properties, attention has been given to the health benefits of tocols in oats. However, little is known about developmental aspects of their accumulation. Moreover, aside from their role in protecting membranes from oxidative damage, their possible physiological roles in planta have largely gone uninvestigated. In this study, we quantified tocol accumulation at five time points during oat seed development, and also compared tocol concentration and composition in the whole seed both to endosperm and embryos at a late stage of seed development. The temporal pattern of accumulation of the tocol subgroups was different. Both tocotrienols and tocopherols steadily increased over the course of seed development; however, tocotrienol progression was sigmoidal and tocopherol linear. By the end of seed development, tocotrienols were the most abundant tocol both in whole seed and in seed with embryos removed. In contrast, embryos contained higher concentrations of tocopherols than tocotrienols late in seed development. Differences in both temporal and spatial distribution during seed development suggest distinct roles for tocotrienols and tocopherols.  相似文献   
2.
Growing female rats were fed diets containing either corn oil (CO) or cottonseed oil (CSO) to determine if the previously reported lowering effect of CSO versus CO on serum total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) was sex specific and to compare the effect of these two oils on serum and tissue concentrations of RRR-alpha-tocopherol (α-T) and RRR-gamma-tocopherol (γ-T), the two major tocopherols in these oils. In a 4-week study, groups of rats (n=10 each) were fed diets containing 100 g/kg of either CO or CSO. TC was lower for group CSO than group CO. Serum concentrations of HDL-C, non-HDL-C, triglycerides (TGs), as well as the TC/ HDL-C ratio and the hepatic concentrations of cholesterol and TGs, were unaffected by diet. For serum and liver, between-group differences were noted for the concentrations of α-T (where values were higher for group CSO) and γ-T (where values were lower for group CSO). These differences reflected differences between the oils in their concentrations of these tocopherols. Thus, CSO has a lowering effect on TC for both sexes, but on HDL-C for male animals only; replacement of CO with CSO results in changes in tocopherol status.  相似文献   
3.
There is no data on the lipid profile of Fagopyrum tataricum grain and its milling products. Therefore, we aimed to assess the phytosterol and tocopherol content and fatty acid profile of the samples of F. tataricum. Grain was milled, then the milling product separated to hull, bran, and two flour fractions, differing in particle size. The highest level of lipids (total fatty acids – 83%, with dominant oleic acid – 40%) was observed in the bran fraction (380 μm > GA > 180 μm). All samples contained some natural cis fatty acids, such as vaccenic acid (C18:1 n-7; ~2.8%) and tocopherol (α-, β-, δ- and γ-tocopherol). The highest content of total tocopherol was also detected in the bran fraction (0.1% of lipids). The content of lipid soluble bioactive substances was different and depended on the size of obtained fraction, therefore properly designed grain processing technology can be used to produce food with high nutritional value.  相似文献   
4.
The grain oils extracted from six genotypes of Cynara species: two globe artichokes (Cynara scolymus L.), two cultivated cardoons (C. cardunculus L. var. altilis DC.) and two wild cardoons (C. cardunculus L. var. sylvestris Lam.), were analysed in order to ascertain their alimentary value. Oil yield, moisture, acidity, peroxide number, UV spectrophotometry and CIE colour parameters, fatty acids, phytosterols and -tocopherol were determined by standard methods. Cynara species which are most promising in terms of quality and quantity of oil were the cardoons, especially those belonging to the wild cardoon genotypes. Triacylglycerols were the dominant constituents together with very little amounts of phospholipids and glycolipids. The high content of oleic and linoleic acids in a balanced ratio, and the low amount of free acids, peroxides, saturated and linolenic acids ensure a good alimentary quality. Distribution of phytosterols was typical of oil from grain of Asteraceae such as sunflower and safflower. Moreover the optimal -tocopherol content offers a guarantee of stability against oxidation.  相似文献   
5.
In the present study, a total of 380 samples of 5 rice varieties were investigated for the presence of aflatoxins (AFs) and tocopherols (Vitamin E) using HPLC, equipped with a fluorescence detector. The data revealed that super basmati rice has the highest mean level of total AFs (12.45 μg/kg) followed by KS-282 (11.2 μg/kg), basmati PK-385 (9.8 μg/kg), Irri-6 (9.7 μg/kg) and the lowest mean level was found in Irri-9 (8.9 μg/kg). Furthermore, the results have shown that the variety with lowest level of AFs has the highest level of tocopherol content; i.e. Irri-9 (53.2 mg/100 g), basmati PK-385 (45.9 mg/100 g), Irri-6 (45.3 mg/100 g), KS-282 (40.4 mg/100 g) and super basmati rice (40.2 mg/100 g). The data has shown correlation (r = −0.62, p < 0.05) between vitamin E content and AFs concentration in different rice varieties. The results are interesting and need further study to investigate the mechanistic background of vitamin E content and its effect on aflatoxins contamination.  相似文献   
6.
The unsaponifiable lipid fraction of plant-based foods is a potential source of bioactive components such as phytosterols, squalene, and tocopherols. The objective of the present study was to determine the levels of phytosterols, and squalene, as well as tocopherols (α and β + γ) in selected grains, seeds, and legumes. The method comprised acid hydrolysis and lipid extraction followed by alkaline saponification, prior to analysis by HPLC. In addition, the fatty acid profile of the foods was determined via total lipid extraction, fatty acid derivitisation and GC analysis. In general, β-sitosterol was the most prevalent phytosterol, ranging in concentration from 24.9 mg/100 g in pumpkin seed to 191.4 mg/100 g in peas. Squalene identified in all foods examined in this study, was particularly abundant in pumpkin seed (89.0 mg/100 g). The sum of α- and β+ γ-tocopherols ranged from 0.1 mg/100 g in rye to 15.9 mg/100 g in pumpkin seeds. Total oil content ranged from 0.9% (w/w) in butter beans to 42.3% (w/w) in pumpkin seed and the type of fat, in all foods examined, was predominantly unsaturated. In conclusion, seeds, grains, and legumes are a rich natural source of phytosterols. Additionally, they contain noticeable amounts of squalene and tocopherols, and in general, their fatty acid profile is favorable.  相似文献   
7.
The fatty acid composition, Acid Value, and the content and composition of tocopherols, tocotrienols, carotenoids, phytosterols, and steryl ferulates were determined in corn germ oil and four post-fermentation corn oils from the ethanol dry grind process. The oxidative stability index at 110 °C was determined for the five oils, and four oils were compared for their stability during storage at 40 °C as determined by peroxide value and hexanal content. The fatty acid composition of all five oils was typical for corn oil. The Acid Value (and percentage of free fatty acids) was highest (28.3 mg KOH/g oil) in corn oil extracted centrifugally from a conventional dry grind ethanol processing facility and for oil extracted, using hexane, from distillers dried grains with solubles (DDGS) from a raw starch ethanol processing facility (20.8 mg KOH/g oil). Acid Value was lowest in two oils extracted centrifugally from thin stillage in a raw starch ethanol facility (5.7 and 6.9 mg KOH/g oil). Tocopherols were highest in corn germ oil (∼1400 μg/g), but tocotrienols, phytosterols, steryl ferulates, and carotenoids were higher in all of the post-fermentation corn oils. Hexane extracted oil from DDGS was the most oxidatively stable as evaluated by OSI and storage test at 40 °C, followed by centrifugally extracted thin stillage oil from the raw starch ethanol process, and centrifugally extracted thin stillage oil from the conventional dry grind ethanol process. Corn germ oil was the least oxidatively stable. When stored at room temperature, the peroxide value of centrifugally extracted thin stillage oil from the raw starch ethanol process did not significantly increase until after six weeks of storage, and was less than 2.0 mequiv. peroxide/kg oil after three months of storage. These results indicate that post-fermentation corn oils have higher content of valuable functional lipids than corn germ oil. Some of these functional lipids have antioxidant activity which increases the oxidative stability of the post-fermentation oils.  相似文献   
8.
The fatty acid profiles and tocopherol and phytosterol contents of crude oils of cress (Lepidium sativum L.) and field pennycress (Thlaspi arvense L.) are reported, along with yields from the corresponding seeds. The physical properties of these oils were also determined, which included oxidative stability, kinematic viscosity, viscosity index, low temperature fluidity, specific gravity, acid value, lubricity, and iodine value. The oil content of dried cress and field pennycress seeds was 22.7 and 29.0 wt%, respectively. The primary fatty acids found in cress oil were oleic (30.6 wt%) and linolenic acids (29.3 wt%), whereas field pennycress oil was principally composed of erucic (32.8 wt%) and linoleic (22.4 wt%) acids. Cress oil contained high concentrations of γ- (1422 ppm) and δ- (356 ppm) tocopherols, whereas α-tocopherol (714 ppm) was the primary tocopherol discovered in field pennycress oil. The overall tocopherol concentrations of cress and field pennycress oils were 1799 and 851 ppm, respectively. The primary phytosterols elucidated in cress and field pennycress oils were sitosterol and campesterol, with avenasterol also present in significant quantity in cress oil. The total phytosterol concentration in cress oil (14.41 mg/g) was greater than that in field pennycress (8.55 mg/g) oil. Field pennycress oil exhibited excellent low temperature fluidity, whereas cress oil was more stable to oxidation and over a range of temperatures displayed lower kinematic viscosities as well as a higher viscosity index. The acid and iodine values of field pennycress oil were lower than those for cress oil, but both oils had excellent lubrication properties.  相似文献   
9.
To reveal the characteristic chemicals of walnuts from different origins, we analyzed fatty acid composition,tocopherols, phytosterols and total phenolic content(TPC) of walnuts from three main producing regions in China. The results showed that walnuts were rich in polyunsaturated fatty acids, and the ratio of ω-6 to ω-3 fatty acids was close to the recommendation of Chinese Nutrition Society. Moreover, walnuts contain high contents of tocopherols(331.20–414.71 mg/kg), phytosterols(97.17–110.35...  相似文献   
10.
Carotenoids and tocols of 20 genotypes of colored barley divided into three groups (A, B, C) were investigated. These included 16 F8 recombinant inbred lines obtained from crosses of four parental lines: 2005 FG, K4-31, L94 and Priora. The aim of the present study was to identify, quantify and profile characterize of tocols and carotenoids. Tocols profile is characterized by the prevalence of tocotrienols on tocopherols. The α-tocotrienol was the most represented tocol isomer, contributing about 53.03% of the total content. The highest α-tocotrienol content (33.67 μg g-1) was found in the blue naked parental genotype 3007 (C-Group). The most abundant carotenoid was lutein on average 86% of total followed by zeaxanthin 10% and by α-carotene 3.40%. The Priora cultivar (C-Group) was the genotype with the highest lutein content (4.10 μg g-1). The study found great variability in the content of carotenoids and tocols along the lines of each group.  相似文献   
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