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排序方式: 共有431条查询结果,搜索用时 15 毫秒
421.
Rosa A Atzeri A Deiana M Melis MP Incani A Corona G Loru D Appendino G Dessì MA 《Journal of agricultural and food chemistry》2008,56(10):3546-3553
This study investigated the effect of synthetic capsiate, a simplified analogue of capsiate, and vanillyl alcohol on the oxidative stress induced by tert-butyl hydroperoxide (TBH) in a line of fibroblasts derived from monkey kidney (Vero cells). In response to the TBH-mediated oxidative stress, a reduction of the levels of total unsaturated fatty acids and cholesterol was observed, and a rise in the concentrations of conjugated dienes fatty acids hydroperoxides and 7-ketocholesterol. Pretreatment with both synthetic capsiate and vanillyl alcohol preserved Vero cells from oxidative damage and showed a remarkable protective effect on the reduction of the levels of total unsaturated fatty acids and cholesterol, inhibiting the increase of MDA, conjugated dienes fatty acids hydroperoxides, and 7-ketocholesterol. Both compounds were effective against peroxidation of cell membrane lipids induced by TBH, with synthetic capsiate essentially acting as a pro-drug of vanillyl alcohol, its hydrophilic hydrolytic derivative. 相似文献
422.
Boschin G Annicchiarico P Resta D D'Agostina A Arnoldi A 《Journal of agricultural and food chemistry》2008,56(10):3657-3663
The intake of lupin-based foods could imply the exposure of consumers to quinolizidine alkaloids. The objectives of this study were to assess the genetic variation among and within 11 geographic regions of Lupinus albus ecotypes, verify the quinolizidine alkaloids amount of alkaloid-poor L. albus and Lupinus angustifolius varieties, and assess the effect of two climatically contrasting Italian environments on the alkaloid content. The quantitation was performed by GC-MS, and in all samples lupanine was the most abundant quinolizidine alkaloid, followed by albine and 13alpha-hydroxylupanine for L. albus and by 13alpha-hydroxylupanine and angustifoline for L. angustifolius. Some regions tended to have a high (Azores) or low (Egypt, Near East, Maghreb) total alkaloids content, but the variation among ecotypes within regions was larger than that among regions following the estimation of variance components. Alkaloid-poor varieties tended to have higher total alkaloid contents when grown in the subcontinental climate site, exceeding in some cases the limit of 0.200 mg/g. 相似文献
423.
Lamperi L Chiuminatto U Cincinelli A Galvan P Giordani E Lepri L Del Bubba M 《Journal of agricultural and food chemistry》2008,56(15):6536-6546
This paper investigates the influence of cultivar (Annurca, Golden Delicious, Red Chief, and Stayman Neepling), rural practice (integrated and organic), and growing region (different Italian regions) on polyphenol composition and antiradical activity of the pulp and skin of apples, as presented to the consumer at the market. Antiradical activity of fruit was strongly related with the total polyphenolic content, determined both by the spectrophotometric Folin-Ciocalteu method ( R (2) = 0.90; P < 0.01) and by HPLC ( R (2) = 0.85; P < 0.01). Considering the edible portion of the fruit, polyphenolics contribute toward explaining approximately 90% of the overall antiradical activity, thus highlighting their important role in human health protection. Therefore, the data indirectly indicated that ascorbic acid and other antiradical molecules differing from polyphenols play a much less important role in explaining the health-protecting properties of apples. Cultivar effect was by far the most important, and Annurca and Golden Delicious were respectively the best and the worst apples from the point of view of the health-protecting attributes. 相似文献
424.
Tavani A Spertini L Bosetti C Parpinel M Gnagnarella P Bravi F Peterson J Dwyer J Lagiou P Negri E La Vecchia C 《Public health nutrition》2006,9(3):369-374
OBJECTIVE: As intake of flavonoids has been associated with reduced risk of coronary heart disease but data on the relation with specific classes of flavonoids are scarce, we assessed the relation between dietary intake of specific classes of flavonoids and the risk of acute myocardial infarction (AMI) in an Italian population.DESIGN: Case-control study. Dietary information was collected by interviewers on a questionnaire tested for validity and reproducibility. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were obtained by multiple logistic regression models including terms for energy and alcohol intake, as well as sociodemographic factors, tobacco and other major recognised risk factors for AMI.SETTING: Milan, Italy, between 1995 and 2003.SUBJECTS: Cases were 760 patients, below age 79 years, with a first episode of non-fatal AMI, and controls were 682 patients admitted to hospital for acute conditions unrelated to diet.RESULTS: A reduced risk of AMI was found for increasing intake of anthocyanidins (OR=0.45, 95% CI 0.26-0.78 for the highest vs. the lowest quintile, Ptrend=0.003) and flavonols (OR=0.65, 95% CI 0.41-1.02, Ptrend=0.02). A tendency towards reduced risks, although not significant, was observed for flavan-3-ols (OR=0.73, 95% CI 0.48-1.10) and total flavonoids (OR=0.74, 95% CI 0.49-1.14). No meaningful heterogeneity was found between the sexes. No association emerged for other flavonoids, including isoflavones, flavanones and flavones.CONCLUSIONS: High intake of anthocyanidins reduced the risk of AMI even after allowance for alcohol, fruit and vegetables, supporting a real inverse association between this class of flavonoids and AMI risk. 相似文献
425.
A retrospective study comparing histopathological and immunopathological features of nasal planum dermatitis in 20 dogs with discoid lupus erythematosus or leishmaniosis
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426.
427.
First evidence of resistance to pyrethroid insecticides in Italian Aedes albopictus populations 26 years after invasion
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Verena Pichler Romeo Bellini Rodolfo Veronesi Daniele Arnoldi Annapaola Rizzoli Riccardo Paolo Lia Domenico Otranto Fabrizio Montarsi Sara Carlin Marco Ballardini Elisa Antognini Marco Salvemini Emanuele Brianti Gabriella Gaglio Mattia Manica Pietro Cobre Paola Serini Enkelejda Velo John Vontas Ilias Kioulos Joao Pinto Alessandra della Torre Beniamino Caputo 《Pest management science》2018,74(6):1319-1327
428.
Mirco?Iotti Pamela?Leonardi Giuliano?VitaliEmail authorView authors OrcID profile Alessandra?Zambonelli 《Biology and Fertility of Soils》2018,54(6):707-716
Tuber magnatum, the Italian white truffle, is the world’s most valuable truffle. Despite the economic importance, its biology and ecology are largely unexplored. This gap of knowledge makes difficult to find reliable methods for its cultivation and to protect and increase the production of the natural productive areas. In this study, the vertical distribution of T. magnatum mycelium in productive soil patches was evaluated using a quantitative PCR (qPCR) approach. Data were then used to develop for the first time a simulation model to predict the mycelial dynamics of T. magnatum at varying soil temperatures and moisture. T. magnatum mycelium was abundant up to 30-cm depth, while the model determined the optimal temperature (20 °C) and water potential (~?0 kPa) for growth of T. magnatum mycelium in soil. Such information could be useful to establish proper irrigation scheduling and to enhance the management of T. magnatum sites, for increasing mycelial growth and fruiting body production. 相似文献
429.
Alessandra?TurriniEmail author Alberico?Bedini Mario?Bonilla?Loor Gaia?Santini Cristiana?Sbrana Manuela?Giovannetti Luciano?AvioEmail author 《Biology and Fertility of Soils》2018,54(2):203-217
Intact whole native AMF communities occurring across a 100-m-long field were used for the evaluation of plant performance, as determined by the actual fungal species colonizing host roots. The soil from distinct plots within a “hot spot” field was collected to set up 54 experimental units where three different plant species were grown, in order to test whether the whole native AMF communities were able to differentially affect plant growth, to assess the genetic identity of the AMF actually colonizing the tested plants and to analyse their community composition in the different hosts. Molecular analyses revealed that plant growth and nutrition of the crop plants were differentially affected by the diverse native arbuscular mycorrhizal communities colonizing the roots of the three plants, whose performance varied depending on the identity of plant hosts and fungal symbionts, more than on a rich and diversified AMF community. Such results, improving our understanding of AMF distribution at the local scale, represent a starting point allowing the selection, isolation and characterization of the most efficient AMF assemblages to be used as inoculants in sustainable food production systems. 相似文献
430.
Alessandra Perfetti-Bolaño Lucila Moreno Roberto Urrutia Alberto Araneda Ricardo Barra 《Water, air, and soil pollution》2018,229(12):390
Penguins can bioaccumulate metals, a portion of which can be deposited in the environment through organic remains such as excrement, carcasses, and eggshells. In order to determine Cu and Pb concentrations and their relationship to soil, organic matter and grain size were determined in 27 samples collected in zones without penguins, penguin transit zones, and Adelie (Pygoscelis adeliae), Chinstrap (P. antarctica), and Gentoo penguin (P. papua) colonies on the Ardley Peninsula, Maritime Antarctica. An atomic absorption spectrophotometry analysis was carried out, organic matter was determined by loss on ignition, and grain size was measured with a laser diffraction particle size analyzer. The principal component analysis shows a relationship between the variables Cu, Pb, and grain size and areas with penguin presence. Cu concentrations in soils varied among areas (χ2, 15.707; p =?0.0004), with higher concentrations in transit zones and penguin colonies (142.63 and 140.79 mg/kg, respectively) than in zones without penguins (83.33 mg/kg). Pb concentrations in soils also varied among areas (χ2, 6.5029; p =?0.0387), and were higher in transit zones (5.92 mg/kg) than in the penguin colonies (4.45 mg/kg). Grain size differed significantly among areas (χ2, 13.506; p =?0.0012), with higher values in transit zones (avg. 37.38 μm) than in penguin colonies (avg. 26.93 μm) and zones without penguins (avg. 20.72 μm). Organic matter did not differ significantly among the studied zones (χ2, 2.0882; p =?0.3520). There is a positive correlation between Cu-Pb (Rho, 0.5532; p =?0.0028), Cu-grain size (Rho, 0.4756; p =?0.0130) and Pb-grain size (Rho, 0.4879; p =?0.0098). The presence of penguins increases Cu concentrations in Antarctic soils due to its bioaccumulation and elimination through excrement; however, the presence of penguins has a minor influence on Pb concentration in soil, probably because this metal is stored efficiently in bones, feathers, and eggshells. 相似文献