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81.
Mechanical injury of sweet cherry fruit causes the disorder ‘surface pitting’, in which skin depressions overlie necrotic lesions in the fleshy mesocarp. Storage at temperatures near 0°C or the transfer of fruit from cool storage to room temperature worsened the disorder. Pretreating the fruit before cool storage with antitranspirant or surface-active agents exacerbated the disorder, but these effects were mitigated by the addition of CaCl2. Low O2, high CO2 and high humidity atmospheres did not affect the disorder, and low pressure storage was beneficial. 相似文献
82.
M Gil N Kontoudakis E González M Esteruelas F Fort JM Canals F Zamora 《Journal of agricultural and food chemistry》2012,60(32):7988-8001
The aim of this paper was to study how maturity and maceration length affect color, phenolic compounds, polysaccharides, and sensorial quality of Cabernet Sauvignon and Tempranillo wines at three stages of grape ripening. Ripeness increased color extractability, phenolic compounds, and polysaccharide concentrations. Moreover, the proanthocyanidin mean degree of polymerization (mDP) and the percentage of prodelphinidins also increased with maturity, whereas the percentage of galloylation decreased. In general, wines from riper grapes contain higher proportions of skin proanthocyanidins. Color and anthocyanin concentration decreased when the maceration was longer, whereas polysaccharide and proanthocyanidin concentrations did the opposite. It was also detected that the mDP and the percentage of prodelphinidins decreased when the maceration was extended, whereas the percentage of galloylation increased. These data seem to indicate that proanthocyanidin extraction from seeds is clearly increased throughout the maceration time. 相似文献
83.
A Cáceres A Peña-Neira A Galvez E Obreque-Slier R López-Solís JM Canals 《Journal of agricultural and food chemistry》2012,60(35):8694-8702
The phenolic composition of wine depends on, among other factors, the grapes used to make it. In this sense, knowledge of the chemical composition of grapes and its association with the resulting wines is an important tool to determine if there is a relationship between the phenolic composition of grapes and the price that these wines obtain in the market. For this purpose, grape skins and seeds from the cultivar Cabernet Sauvignon from the central region of Chile, in 2009 and 2010 vintages from two ripening points, were subjected to chemical and phenolic analyses, as were the wines made from these grapes. Grapes and the corresponding wines from three retail price wine categories, U.S. $6-8, U.S. $28-30, and U.S. $150-160, were evaluated. No differences were found across the price categories in the chemical analysis of grapes. Berry skins and wines from the higher price categories presented a higher concentration only of total tannins, and the differences in their concentrations were only among the different fractions of proanthocyanidins in the skins, seeds, and wines; there were no differences in their proportions. A seasonal effect influenced the concentrations of certain compounds in grapes and led to a decrease in the concentration of total phenols, total tannins, and total anthocyanins between sampling dates as harvesting moved toward the common commercial grape harvest in Chilean viticulture. 相似文献
84.
García-Bocanegra I Arenas-Montes A Lorca-Oró C Pujols J González MA Napp S Gómez-Guillamón F Zorrilla I Miguel ES Arenas A 《Veterinary research》2011,42(1):88
ABSTRACT: Although the importance of wild ruminants as potential reservoirs of bluetongue virus (BTV) has been suggested, the role played by these species in the epidemiology of BT in Europe is still unclear. We carried out a serologic and virologic survey to assess the role of wild ruminants in the transmission and maintenance of BTV in Andalusia (southern Spain) between 2006 and 2010.A total of 473 out of 1339 (35.3%) wild ruminants analyzed showed antibodies against BTV by both ELISA and serum neutralization test (SNT). The presence of neutralizing antibodies to BTV-1 and BTV-4 were detected in the four species analyzed (red deer, roe deer, fallow deer and mouflon), while seropositivity against BTV-8 was found in red deer, fallow deer and mouflon but not in roe deer. Statistically significant differences were found among species, ages and sampling regions. BTV RNA was detected in twenty-one out of 1013 wild ruminants (2.1%) tested. BTV-1 and BTV-4 RNA were confirmed in red deer and mouflon by specific rRT-PCR.BTV-1 and BTV-4 seropositive and RNA positive wild ruminants, including juveniles and sub-adults, were detected years after the last outbreak was reported in livestock. In addition, between the 2008/2009 and the 2010/2011 hunting seasons, the seroprevalence against BTV-1, BTV-4 and BTV-8 increased in the majority of provinces, and these serotypes were detected in many areas where BTV outbreaks were not reported in domestic ruminants. The results indicate that wild ruminants seem to be implicated in the dissemination and persistence of BTV in Spain. 相似文献
85.
Zhang H Lunney JK Baker RB Opriessnig T 《Veterinary immunology and immunopathology》2011,140(1-2):152-158
The objective of this study was to determine cytokine and chemokine mRNA expression profiles in tracheobronchial lymph nodes from pigs singularly infected with porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (MHYO), or coinfected with both. Twenty-eight pigs were randomly assigned to one of four groups: (1) negative controls (NEG), (2) inoculated with MHYO (IMHYO), (3) inoculated with MHYO and PCV2 (CoI), and (4) inoculated with PCV2 (IPCV2). MHYO infection significantly (P<0.05) stimulated innate cytokines, IL1B and IL8. PCV2 infection significantly stimulated expression of IFNG, IL8, NOS2A and chemokines CCL2, CCL5, and CXCL10. IFNB, IL1B and IL12 were slightly increased with PCV2 infection and IFNA and IL4 were significantly downregulated. Compared to NEG pigs, coinfection resulted in a significant increase in expression of IFNG, IL1B, IL8, CCL5, CXCL10, and weak stimulation of IFNB, IL6 and IL10; IL13 and IFNA were significantly downregulated. Overall MHYO potentiated PCV2 infection by increasing IFNG and IL10 mRNA expression levels. The increase of IFNG and chemokines and decrease of IFNA in IPCV2 and CoI pigs were correlated with increased severity of lymphoid lesions and the presence of PCV2 antigen. In summary, this work provided evidence that the increased severity of lesions in PCV2 and MHYO coinfected pigs was associated mainly with the presence of PCV2 antigen and alterations of cytokine mRNA expression profiles. 相似文献
86.
Genetic and immunobiological diversities of porcine reproductive and respiratory syndrome genotype I strains 总被引:1,自引:0,他引:1
Darwich L Gimeno M Sibila M Diaz I de la Torre E Dotti S Kuzemtseva L Martin M Pujols J Mateu E 《Veterinary microbiology》2011,150(1-2):49-62
Genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV) has been based on ORF5/GP5 and ORF7/N protein variations. Complete viral genome studies are limited and focused on a single or a few set of strains. Moreover, there is a general tendency to extrapolate results obtained from a single isolate to the overall PRRSV population. In the present study, six genotype-I isolates of PRRSV were sequenced from ORF1a to ORF7. Phylogenetic comparisons and the variability degree of known linear B-epitopes were done considering other available full-length genotype-I sequences. Cytokine induction of all strains was also evaluated in different cellular systems. Non structural protein 2 (nsp2) was the most variable part of the virus with 2 out of 6 strains harboring a 74 aa deletion. Deletions were also found in ORF3 and ORF4. Phylogenetic analyses showed that isolates could be grouped differently depending on the ORF examined and the highest similarity with the full genome cluster was found for the nsp9. Interestingly, most of predicted linear B-epitopes in the literature, particularly in nsp2 and GP4 regions, were found deleted or varied in some of our isolates. Moreover, 4 strains, those with deletions in nsp2, induced TNF-α and 3 induced IL-10. These results underline the high genetic diversity of PRRSV mainly in nsp1, nsp2 and ORFs 3 and 4. This variability also affects most of the known linear B-epitopes of the virus. Accordingly, different PRRSV strains might have substantially different immunobiological properties. These data can contribute to the understanding of PRRSV complexity. 相似文献
87.
88.
Roberto Quiroz Joan O. Grimalt Pilar Fernandez Lluis Camarero Jordi Catalan Evzen Stuchlik Hansjoerg Thies Ulrike Nickus 《Water, air, and soil pollution》2011,215(1-4):655-666
Polycyclic aromatic hydrocarbons (PAHs) were analyzed in 70 soils distributed in mountain areas such as Montseny (300?C1,700 m), Pyrenees (1,500?C2,900 m), Alps (1,100?C2,500 m), and Tatras (1,400?C1,960 m). Average total PAH concentrations, excluding retene and perylene, were about 400 ng/g in the Pyrenees and 1,300?C1,600 ng/g in the other mountain ranges. No correlations between PAH concentrations and total organic carbon were observed. Retene was the major PAH in the Pyrenean soils of lower altitude. No altitudinal dependence was found between soil PAH concentrations and elevation for the whole dataset. However, in the Tatra soils a statistically significant correlation with altitude was observed involving higher concentrations at higher altitude. This correlation was due to the statistically significant altitudinal dependence of the more volatile PAHs. Another observed altitudinal trend concerned the benz[a]anthracene/(benz[a]anthracene + chrysene + triphenylene) and the benzo[a]pyrene/(benzo[a]pyrene + benzo[e]pyrene) ratios that exhibited a decrease in the more chemically labile compounds, benz[a]anthracene and benzo[a]pyrene, respectively, in the soils located at higher altitude. This observation is consistent with the expected higher photooxidation at higher mountain altitude. 相似文献
89.
Junu Shrestha Jean Christophe Clément Joan G. Ehrenfeld Peter R. Jaffe 《Water, air, and soil pollution》2011,220(1-4):213-223
Riparian wetlands are subject to nitrogen enrichment from upgradient agricultural and urban land uses and also from flooding by nitrogen-enriched surface waters. The effects of this N enrichment on wetland soil biogeochemistry may be mediated by both the presence of plants and the presence of redox-active compounds, specifically iron oxides in the soil. Despite the extensive research on wetland N cycling, the relative importance of these two factors on nitrogen is poorly known, especially for forested wetlands. This study evaluates the responses of the N and the Fe cycles to N enrichment in a riparian forested wetland, contrasting vegetated field plots with plots where the vegetation was removed to test the role of plants. Furthermore, in vitro anaerobic incubations of the experimental soils were performed to track Fe chemical changes over time under anoxic or flooded conditions. Wetland soils treated with N in form of urea, as expected, had significantly higher amounts inorganic nitrogen. In the soils where vegetation was also removed, in addition to inorganic nitrogen pool, increase in organic nitrogen pool was also observed. The results demonstrate the role of vegetation in limiting the effects excess urea has on different soil nitrogen pools. Results from anaerobic incubation of the experimental soils demonstrated the effects of N enrichment on the wetland Fe cycle. The effects of excess nitrogen and the role of vegetation on the Fe cycle in riparian wetland soil became more evident during anaerobic incubation experiments. At the end of the field experiment, Fe concentrations in the soils under the treatments were not significantly different from the control soils at the 5% confidence level. However, during the anaerobic incubation experiment of soils collected at the end of the experiment from these plots, the N-enriched soils and the unvegetated soils maintained significantly elevated concentrations of reducible Fe(III) for the initial 2-week period of incubation, and the soils collected from the plots with both the treatments had the highest Fe(III) concentrations. After 20 days of incubation, however, the Fe(III) concentrations decreased to the similar concentrations in all the incubated soils. The study clarifies the roles vegetation play in mediating the effects of N enrichment and also demonstrates that N enrichment does affect wetland redox cycle, which has strong implications on ecosystem services such as water quality improvement. 相似文献
90.
Ana Rivera Daniel Fenero Antoni Almirall Juan José Ferreira Joan Simó Marçal Plans Roser Romero del Castillo Francesc Casañas 《Genetic Resources and Crop Evolution》2013,60(6):1885-1898
Few studies have explored sensory variability in beans. We used geographic, agronomic, morphological, and genetic criteria to select numerous groups of landraces from among the many collected in Catalonia (northeast Spain). Beans cultivated in a single location to avoid environmental effects were submitted to a trained panel for sensory analysis. We used multiple linear regression to explore whether the flavor and texture of the seed (evaluable only by tasting after cooking) can be estimated from easily measurable traits like the appearance of the beans. The degree of variability found for all sensory traits (coefficients of variation: 20–70 %) was similar to that of agronomic traits; however, entries were grouped differently for sensory and agronomic traits, suggesting independent evolution. Negative genotypic correlations between some sensory traits will probably hinder attempts to achieve ideotypes combining low seed-coat perceptibility, low mealiness, and high flavor. Regressions between easily measurable traits (agronomic and culinary traits and appearance of the seeds) and flavor and texture yielded R2 values ranging from 0.47 to 0.64. We consider these values good enough for rough screening of sensory attributes in genetic resources studies or breeding. 相似文献