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761.
Gómez ME Igartuburu JM Pando E Luis FR Mourente G 《Journal of agricultural and food chemistry》2004,52(15):4791-4794
In this paper, we describe the study and characterization of the lipids from lees of Sherry wine, one of the main byproducts from the wine-making industry in the Jerez/Xeres/Sherry denomination of the origin zone in Jerez de la Frontera, Spain. The lipid content, extractability, classification, fatty acid composition, and its main chemical characteristics have been determined in order to evaluate their potential use as a food or food additive. 相似文献
762.
OBJECTIVE: To assess the accuracy of self-reported waist and hip circumferences and the waist-to-hip ratio (WHR) by comparison with measured waist and hip circumferences and WHR in a sample of middle-aged men and women. DESIGN: Analysis of measured and self-reported waist and hip data from participants in the Oxford cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Oxford). PARTICIPANTS: Four thousand four hundred and ninety-two British men and women aged 35-76 years. RESULTS: Spearman's rank correlation coefficients between measured and self-reported waist, hip and WHR were 0.80, 0.74 and 0.44, respectively, for men and 0.83, 0.86 and 0.62 for women. Waist was underestimated, on average, by 3.1 (standard deviation (SD) 5.6) cm in men and 1.9 (SD 5.4) cm in women. The extent of underestimation was greater in participants with larger waists, older participants and women with greater body mass index (BMI). Hip was underestimated by a mean of 1.8 (SD 4.9) cm in men and 1.2 (SD 4.5) cm in women; the extent of underestimation was greater in participants with larger hip circumference and older participants. On average, WHR was underestimated by less than 2% by men and women; the extent of underestimation was greater among those with larger WHR, older people and those with greater BMI. Using self-reported values, the proportion of classification to the correct tertile was over 65% for waist and hip measurements. For WHR this proportion was 50% among men and 60% among women. CONCLUSIONS: Self-reported waist and hip measurements in EPIC-Oxford are sufficiently accurate for identifying relationships in epidemiological studies. 相似文献
763.
Winemaking waste solids (WS, resulting from red grapes after fermentation and distillation to recover spirits) were subjected to various processing schemes for isolating fractions with antioxidant activity. The liquors entrapped in WS as received were separated by pressing and freeze-dried to yield a fraction with antioxidant activity (measured as DPPH radical scavenging capacity) comparable to those of synthetic antioxidants. A second approach based on the direct processing of raw WS in sulfuric acid medium under fixed operational conditions and further extraction of hydrolysis liquors with ethyl acetate enabled the isolation of a fraction with higher antioxidant ability at an improved yield. The most favorable approach started with a washing stage leading to liquors (which were directly freeze-dried to yield 1.20 g of extract/100 g of oven-dry WS and presented an EC50 of 0.41 g of extract/L) and washed solids, which were dried and subjected to hydrolytic processing (i) with water as a reactive in an autocatalyzed reaction (autohydrolysis) or (ii) with sulfuric acid solutions to give an ethyl acetate-soluble fraction with improved antioxidant properties (EC50 in the range of 0.18-0.40 g/L). Samples from washing liquors and processing of washed solids in aqueous medium were subjected to chromatographic fractionation and analysis to give isolates with remarkable antioxidant activity (with EC50 as low as 0.07 g/L) and to identify their major components. 相似文献
764.
Mariela Czerniczyniec Silvia Farías Jorge Magallanes Daniel Cicerone 《Water, air, and soil pollution》2007,180(1-4):75-82
This study qualifies and quantifies the effects of pH, hardness, alkalinity, salinity and bone calcination temperature related with the adsorption of As(V) onto biogenic hydroxyapatite (HAPb) obtained from cow-charred bones. Arsenic contamination of surface and subsurface waters is widely extended in Argentina. It is a problem of major concern, particularly in rural and suburban areas where there are not water treatment plants for supplying of drinking water. HAPb is a natural material, whose absorbent properties can be used for the design of low-cost technologies for As(V) abatement in water. In this work HAPb has been characterized by physical and chemical analysis (XRD, SEM, EDAX, BET, and electrophoretic mobility). A Plackett–Burman screening experimental design allowed us to determine the main variables affecting the efficiency of As(V) sorption onto HAPb. Based on these variables and with a design of higher order we developed a model of the system to study its behaviour. Data collection was planned through a Doehlert experimental design and a back propagation artificial neural network was used to work it out. Results showed that salinity is the major variable affecting the efficiency of the As(V) immobilization process but pH and hardness should be taken into account because of associations among them. 相似文献
765.
Encarna Cayuela Alicia Muñoz‐Mayor Francisco Vicente‐Agulló Elena Moyano Jose O. Garcia‐Abellan Maria T. Estañ Maria C. Bolarín 《植物养料与土壤学杂志》2007,170(4):479-484
Agricultural productivity is worldwide subjected to increasing salinity problems. Various strategies are applied to overcome the deleterious effects of salinity on plants. This study was conducted in order to determine whether drought pretreatment of seedlings or seed pretreatment with NaCl increases the long‐term salinity resistance of tomato (Solanum lycopersicum L.) and whether the adaptive response to salinity is accompanied by physiological changes throughout the plant‐growth cycle. When plants were pretreated at the five‐leaf growth stage, the plant dry weight was significantly higher in drought‐pretreated than in non‐pretreated plants after 50 d of salt treatment. The positive effect of drought pretreatment applied at the five‐leaf stage was maintained throughout the entire growth cycle, as fruit yield of drought‐pretreated plants was 40% higher than that of non‐pretreated plants at the end of the harvest period (150 d of 70 mM NaCl treatment). Moreover, the most productive plants maintained lower Na+ and Cl– accumulation in their leaves until the end of the growth cycle, which shows that adaptation is a long‐term response during which the plants adjust their physiology to the environmental conditions. Salt resistance was also improved through seed pretreatment with NaCl. In conclusion, drought pretreatment applied at the five‐leaf stage or seed pretreatment with NaCl provide an alternative way to enhance salt resistance in tomato, and the increase in yield is associated with physiological changes throughout the plant‐growth cycle. 相似文献
766.
Macedo ML Damico DC Freire Md Toyama MH Marangoni S Novello JC 《Journal of agricultural and food chemistry》2003,51(10):2980-2986
This study describes the purification of an N-acetylglucosamine-binding lectin from Koelreuteria paniculata seeds and its effects on the larval development of Callobruchus maculatus and Anagasta kuehniella. The lectin (KpLec) was characterized and isolated by gel filtration, affinity column, and reverse phase chromatography. SDS-PAGE indicated that this lectin is a dimer composed of subunits of 22 and 44 kDa. The N terminus exhibited 40% similarity with Urtiga dioica agglutinin. KpLec was tested for anti-insect activity against C. maculatus and A. kuehniella. With regard to C. maculatus, an artificial diet containing 0.7 and 1% KpLec produced LD(50) and ED(50) value, respectively. However, for A. kuenhiella, an artificial diet containing 0.65% KpLec produced an LD(50), whereas 0.2% KpLec produced an ED(50). The transformation of genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. 相似文献
767.
Brunet MJ Bladé C Salvadó MJ Arola L 《Journal of agricultural and food chemistry》2002,50(9):2708-2712
The processes of absorption, blood transport, tissular distribution, metabolism, and excretion are at present understood very little. The aim of this study was to investigate blood transport and identify which principal plasma proteins in humans and rats bind to monomeric catechin and procyanidins in red wine ex vivo. Human and rat plasma and serum were incubated with (+)-catechin and procyanidins from grape seed, the origin of red wine catechins. Proteins were separated by SDS-PAGE and native-PAGE to determine which proteins bound to these compounds. The principal protein that bound to (+)-catechin in each species was sequenced. SDS-PAGE showed that (+)-catechin and procyanidins mainly bound to a protein of about 80 kDa in rats and 35 kDa in humans. Their sequencing indicated that these proteins were apo A-I in humans and transferrin in rats. The fact that red wine procyanidins bind to both proteins suggests that they may have a role in reverse cholesterol transport and in the oxidizing action of iron. 相似文献
768.
Díaz P Señoráns FJ Reglero G Ibañez E 《Journal of agricultural and food chemistry》2002,50(22):6468-6472
An experimental design has been used to optimize the extraction of volatile compounds from summer truffle aroma (Tuber aestivum) by using headspace solid phase microextraction. The extracted compounds have been analyzed by gas chromatography with a flame ionization detector and by gas chromatography-mass spectrometry (GC-MS). In an attempt to develop an objective method to fully characterize truffle aroma, a fiber of medium polarity (for flavors) was used to avoid discrimination toward very nonpolar and polar volatile compounds. To optimize the extraction conditions, a response surface experimental design was applied considering three factors such as extraction temperature, equilibrium time, and extraction time. From the statistical analysis of the experimental design, it was possible to determine that the most important factor influencing the abundance of aroma compounds was the extraction temperature. Optimal extraction temperature was established at approximately 50 degrees C. By using GC-MS, it was possible to identify 37 compounds, most of them previously described as responsible for truffle aroma. 相似文献
769.
B. Z. Siegel Michael Lasconia Elizabeth Yaeger S. M. Siegel 《Water, air, and soil pollution》1984,23(1):15-24
Seed germination and early growth were unexpectedly resistant to Hg-vapor at air saturation levels (14 μg L?1). Among 15 species and cultivars tested, inhibition of shoot or root growth in excess of 50% was not seen, but occasional stimulation was noted. During extended (70 to 75 days) cultivation at Hg-vapor saturation, inhibitory effects on growth increased with time, and later effects on abscission and necrosis were more severe. Seven days exposures confirmed juvenile resistance at air saturation levels and mature plant sensitivity, expressed by massive abscission at 0.05 μg L?1. It is suggested that Hg-vapor accelerates senescence-related processes via elevated ethylene production. Evidence suggests that elemental Hg, not ionic Hg, is the active toxicant. An ecophysiological role for Hg-vapor in volcanically active regions is suggested. 相似文献
770.
M. I. Mínguez-Mosquera M. Jarén-Galán B. Gandul-Rojas 《Water, air, and soil pollution》1992,65(3-4):195-213
A study of the algal pigments of the biomass from aerobic treatment ponds was made with the aim of supporting other procedures to identify the predominant species that grow in the experimental condition assayed. Chlorophillic and carotenoids pigments were separated and purified by TLC for later identification and quantification by HPLC. A significant predominance of fucoxanthin and diadinoxanthin which are specific of Diatoms were found, as well as very low proportions of other non-specific pigments from other minor growing species. The absence of chlorophyll ‘b’ and a low level of ‘c’ owing to a possible coexistence of Diatom and Cyanophyceae in the culture, must be emphasized. In the experimental conditions assayed the addition of silicates to the waste water promotes the growth of Diatoms specifically Fragilaria pinnata, and also induces the formation of a secondary microflora of Cyanophyceae type with bentonic characteristics, mainly Phormidium fragile, the principal characteristics of which, are a ready tendency to sedimentation and a large size, facilitating their separation by filtration or decantation. 相似文献