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排序方式: 共有237条查询结果,搜索用时 14 毫秒
101.
Romani A Lapucci C Cantini C Ieri F Mulinacci N Visioli F 《Journal of agricultural and food chemistry》2007,55(4):1315-1320
We characterized "Olivastra Seggianese" extra virgin olive oil (EVOO) and evaluated its chemical and sensory characteristics and antioxidant and antiradical activities during storage under novel conditions. Two oils (A and B) were analyzed for the commodity characteristics at blending (t0) and after 9, 12, and 18 months; panel tests were performed and minor polar compounds (MPC) content was assessed at blending (t0) and after 6, 9, 12, and 18 months. Antioxidant and antiradical activities in vitro were evaluated at t0 and after 12 months, by human low density lipoprotein (LDL) and 1,1-diphenyl-2-picrylhydrazil radical (DPPH*) tests. Oil A, which had an initially higher MPC content, possessed "harder" organoleptic characteristics than oil B, which had a lower MPC content and was endowed with a "smoother" taste profile. Statistical analyses showed that secoiridoids, particularly deacetoxy-oleuropein aglycone, should be quantified to evaluate EVOO stability during storage. The antioxidant activity toward human LDL was linked to MPC content and to storage time. The tests on the stable free radical DPPH* confirmed the results on human LDL. We propose this as an additional parameter to evaluate olive oil quality and stability over time. 相似文献
102.
Christian Walzer Angelika Url Nadia Robert Anna Kübber-Heiss Norbert Nowotny Peter Schmidt 《Journal of zoo and wildlife medicine》2003,34(1):36-46
Numerous cases of ataxia, hind limb paresis, and paralysis have occurred in cheetah (Acinonyx jubatus) cubs over the past 10 yr within the European Endangered Species Program population, including 12 in mainland Europe, two in the British Isles, one in Namibia, and one in Dubai. The condition is the most important medical factor limiting European cheetah population growth. Eight cubs at the Salzburg Zoo, Austria, were affected. They demonstrated upper motor neuron lesions when alive and bilateral, symmetrical myelin degeneration of the spinal cord on necropsy. Ballooning of myelin sheaths surrounded mostly preserved axons, and no spheroids, characteristic of acute axonal degeneration, were found. Myelin loss markedly exceeded axonal degeneration. The syndrome's etiology is unclear, although viral, bacterial, parasitic, genetic, nutritional-metabolic, toxic, and physical causes have been considered. 相似文献
103.
Ben Amara-Dali W Karray N Lesieur P Ollivon M 《Journal of agricultural and food chemistry》2005,53(26):10018-10025
The thermal and structural behaviors of anhydrous goat's milk fat (AGMF) have been determined as a function of temperature using a powerful technique allowing simultaneous time-resolved synchrotron X-ray diffraction as a function of temperature (XRDT) and high-sensivity differential scanning calorimetry (DSC) measurements from the same sample. This first paper, aiming at the characterization of the physical properties of AGMF, we examine crystalline organizations made by triacylglycerols (TG) upon slow cooling at /dT/dt/ = 0.1 degrees C/min from 45 to -20 degrees C in order to approach system equilibrium. Three overlapped exotherms were observed by DSC upon cooling, whereas four endotherms were found on the subsequent heating at 1 degrees C/min. XRDT evidenced that AGMF crystallizes under four different lamellar structures, two with double-chain length packings at 41.5 and 38.2 angstroms and two with triple-chain lengths of 72 and 64.7 angstroms stacking. Simultaneous wide-angle XRDT has shown that initial nucleation mainly occurs in a packing of beta' type from approximately 26 degrees C, although some transient presence of alpha was detected. The absence of polymorphic transition, on heating, until final melting (approximately 40 degrees C) demonstrated the relative stability of the structures formed. 相似文献
104.
Al-Delaimy WK van Kappel AL Ferrari P Slimani N Steghens JP Bingham S Johansson I Wallström P Overvad K Tjønneland A Key TJ Welch AA Bueno-de-Mesquita HB Peeters PH Boeing H Linseisen J Clavel-Chapelon F Guibout C Navarro C Quirós JR Palli D Celentano E Trichopoulou A Benetou V Kaaks R Riboli E 《Public health nutrition》2004,7(6):713-722
BACKGROUND: In addition to their possible direct biological effects, plasma carotenoids can be used as biochemical markers of fruit and vegetable consumption for identifying diet-disease associations in epidemiological studies. Few studies have compared levels of these carotenoids between countries in Europe. OBJECTIVE: Our aim was to assess the variability of plasma carotenoid levels within the cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC). METHODS: Plasma levels of six carotenoids--alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, lutein and zeaxanthin--were measured cross-sectionally in 3043 study subjects from 16 regions in nine European countries. We investigated the relative influence of gender, season, age, body mass index (BMI), alcohol intake and smoking status on plasma levels of the carotenoids. RESULTS: Mean plasma level of the sum of the six carotenoids varied twofold between regions (1.35 micromol l(-1) for men in Malm?, Sweden vs. 2.79 micromol l(-1) for men in Ragusa/Naples, Italy; 1.61 micromol l(-1) for women in The Netherlands vs. 3.52 micromol l(-1) in Ragusa/Naples, Italy). Mean levels of individual carotenoids varied up to fourfold (alpha-carotene: 0.06 micromol l(-1) for men in Murcia, Spain vs. 0.25 micromol l(-1) for vegetarian men living in the UK). In multivariate regression analyses, region was the most important predictor of total plasma carotenoid level (partial R(2)=27.3%), followed by BMI (partial R(2)=5.2%), gender (partial R(2)=2.7%) and smoking status (partial R(2)=2.8%). Females had higher total carotenoid levels than males across Europe. CONCLUSIONS: Plasma levels of carotenoids vary substantially between 16 different regions in Italy, Greece, Spain, France, Germany, the UK, Sweden, Denmark and The Netherlands. Compared with region of residence, the other demographic and lifestyle factors and laboratory measurements have limited predictive value for plasma carotenoid levels in Europe. 相似文献
105.
Nadia Ben Brahim Amel Salhi Nidhal Chtourou Daniel Combes Mohamed Marrakchi 《Genetic Resources and Crop Evolution》2002,49(4):429-438
Isozyme variation and phylogenetic relationships between ten annual andperennial Lathyrus species: L.aphaca, L.articulatus, L.cicera, L.hirsutus, L.latifolius, L.nissolia, L.odoratus, L.ochrus, L.sativus and L.sylvestris were studied. Four enzyme systems,leucine-amino-peptidase (LAP), 6-phosphogluconatedeshydrogenase (6-PGD), glutamateoxalo-acetate transaminase (GOT) and phosphoglucoisomerase(PGI) were analyzed, using gel electrophoresis. Fivepolymorphic loci were detected and eleven alleles were identified at these loci.Zymogram data revealed that almost all-present species studied exhibited isozymepolymorphism. L. latifolius andL. sylvestris maintain high levels ofisozyme diversity, which is probably associated with the perenniality of thesetwo species and their predominantly outcrossing reproduction system. Incontrast, the low level of genetic diversity observed in other species isattributed to their breeding systems. These species are annuals and have higherproportions of selfing. The distribution of genetic variation within and amongspecies showed large genetic differences between the analysed species.PGD-1 andPGD-2 loci contributed the most to thedistinction between species. GOT-2,LAP-1 and PGI-1loci contributed to the distinction within species. The low level of gene flowrevealed could be partly related to the high level of autogamy in the majorityof species. The regroupement of species revealed by Nei's genetic similarityagrees only in parte with Kupicha's classification based on morphologicalcharacters. Thus, these isozymic markers are important in germplasm collectionand conservation. 相似文献
106.
The occurrence and characterization of N2-fixing azospirilla in some Egyptian soils has been investigated. Seven soils, representing a wide range in texture and properties were selected from different localities in Egypt. The highest nitrogenase activity reported for soil samples under investigation were related to numbers of N2-fixing microorganisms (Azotobacter spp., Azospirillum spp., and Clostridium spp.). Seven strains of azospirilla were isolated and purified. Based on morphological characteristics, three types of cell morphology were distinguished. Cultural and physiological characteristics as well as nitrogenase activity of representative isolates in presence of different concentrations of NaCl were determined. According to the physiological properties studied, all isolates were classified as members of Azospirillum brasilense. 相似文献
107.
Evaluation of the phenolic content in the aerial parts of different varieties of Cichorium intybus L
Innocenti M Gallori S Giaccherini C Ieri F Vincieri FF Mulinacci N 《Journal of agricultural and food chemistry》2005,53(16):6497-6502
Fresh aerial parts of different chicory varieties: green chicory (c.v. "Catalogna"), two red chicory varieties ("radicchio rosso di Chioggia" and "radicchio rosso di Treviso"), and Witloof or Belgian endive were analyzed by HPLC/DAD/MS. The chromatographic fingerprint was diagnostic for each variety. A monocaffeoyl tartaric acid, chlorogenic acid, and chicoric acid were detected in all the varieties, while cyanidin 3-O-glucoside, delphinidin 3-O-(6' malonyl) glucoside, and cyanidin 3-O-(6' malonyl) glucoside were the main phenolic compounds in the red varieties. The flavonoidic compounds, quercetin 3-O-glucuronide and luteolin 7-O-glucuronide, were absent in the Witloof sample. The phenolic compounds from total leaves were the same as those obtained from only the colored parts; nevertheless, the total amount was remarkably lower with a decrease of up to 80% for Belgian endive. Chemical stability at high temperature was observed for the phenolic fraction from the green variety after decoction at 100 degrees C for 30 min. 相似文献
108.
Chinnici F Gaiani A Natali N Riponi C Galassi S 《Journal of agricultural and food chemistry》2004,52(1):3-7
A rapid HPLC-DAD determination of phenols in apple using an RP monolithic column is reported. Because of the hydrodynamic advantages offered by this kind of column and the use of acidified acetonitrile as eluent, assays of apple extracts can be performed in <21 min. Assays of pulp and peel extracts were carried out without the need for time-consuming sample pretreatment except filtration. Several flavanols, hydroxycinnamic acids, dihydrochalcones, and six quercetin glycosides were identified and quantified. A seventh quercetin derivative, two chalcone-related compounds, and three hydroxycinnamic derivatives were also found. Peels proved to be richer in phenols than pulps, the former being composed mainly of (-)-epicatechin, procyanidin B2, chlorogenic acid, phloridzin, hyperin, and avicularin. In pulps, where the chlorogenic acid was the principal phenolic compound, quercetin glycosides were found in very low amounts. 相似文献
109.
The chitin biosynthesis inhibitor diflubenzuron and its analog BAY SIR 8514 are equitoxic for eggs ofSpodoptera littoralis. BAY SIR 8514 residues on alfalfa fed toSpodoptera larvae were more toxic than diflubenzuron residues, whereas BAY SIR 8514 topically applied to these larvae was consistently twice as toxic as diflubenzuron, according to different criteria. 相似文献
110.
Hammouchi M Loutfi C Sebbar G Touil N Chaffai N Batten C Harif B Oura C El Harrak M 《Veterinary microbiology》2012,160(1-2):240-244
Peste des petits ruminants virus (PPRV) recently caused a serious outbreak of disease in Moroccan sheep and goats. Alpine goats were highly susceptible to PPRV with mortality rates approaching 100%, as opposed to local breeds of sheep which were less susceptible to the disease. The relative susceptibility of alpine goats was investigated through an experimental infection study with the Moroccan strain of PPRV. Severe clinical signs were observed in the alpine goats with virus being excreted through ocular, nasal and oral routes. No difference in the severity of the disease in goats was observed with different inoculation routes and transmission of the virus by direct contact was confirmed. This study confirmed the susceptibility of the alpine goat to PPRV infection and describes a challenge protocol that effectively and consistently reproduced severe clinical signs of PPR in experimentally infected goats. 相似文献