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11.
The volatile composition (volatile phenols, phenolic aldehydes, furanic compounds, lactones, phenyl ketones, and other related compounds) of Spanish oak heartwood of Quercus robur, Quercus petraea,Quercus pyrenaica, and Quercus faginea was studied by gas chromatography/mass spectrometry, in relation to the processing in barrels cooperage and in relation to the French oak of Quercus robur (Limousin) and Quercus petraea (Allier) and American oak of Quercus alba (Missouri), which are habitually used in cooperage. The volatile composition of seasoned oak woods varied according to individual trees, species, and origins, and the differences were more significant in Spanish species with respect to American species than with respect to French species. The toasting process influenced the volatile composition of wood. It led to high increases in the concentration of volatile phenols, furanic aldehydes, phenyl ketones, and other related structures, but the effect on w-lactones levels depended on species and origin. The volatile composition in Spanish oak species evolved during toasting like in French and American oak, but quantitative differences were found, especially important in American species with respect to European species.  相似文献   
12.
A red Rioja wine was aged in barrels made of Spanish oak wood (Quercus robur, Quercus petraea,Quercus pyrenaica, and Quercus faginea) during 21 months. The concentrations of some volatile compounds [syringaldehyde, vanillin, eugenol, maltol, guaiacol, 4-ethylphenol, cis and trans isomers of beta-methyl-gamma-octalactone, 2-furfuraldehyde, 5-methyl-2-furfuraldehyde, 5-(hydroxymethyl)-2-furfuraldehyde, and furfuryl alcohol] were studied in these wines and compared with those of the same wine aged in barrels made from French oak of Q. robur (Limousin, France) and Q. petraea (Allier, France) and American oak of Quercus alba (Missouri). Similar concentrations of these compounds were found in wines aged in Spanish and French oak wood barrels, and significantly different concentrations were found with respect to wines aged in barrels made of American oak wood, indicating a different behavior. Thus, wines with different characteristics were obtained, depending on the kind of wood. Also, the kind of wood had an important influence on sensory characteristics of wine during the aging process. Spanish oak wood from Q. robur, Q. petraea, and Q. pyrenaica can be considered to be suitable for barrel production for quality wines, because a wine aged in barrels made of these Spanish oak woods showed similar and intermediate characteristics to those of the same wine aged in French and American oak woods usually used in cooperage.  相似文献   
13.
A collaborative study was conducted to determine the total dietary fiber (TDF) content of food and food products, using a combination of enzymatic and gravimetric procedures. The method was basically the same as published earlier (J. Assoc. Off. Anal. Chem. (1984) 67, 1044-1052), with changes in the concentration of alcohol and buffers, time of incubation, sample preparation, and some explanatory notes, all with the intent of decreasing the coefficient of variation (CV) of the method. Duplicate blind samples of soy isolate, white wheat flour, rye bread, potatoes, rice, wheat bran, oats, corn bran, and whole wheat flour were analyzed by 9 collaborators. TDF was calculated as the weight of the residue minus the weight of protein and ash. CV values of the data from all laboratories for 7 of the samples ranged from 1.56 to 9.80%. The rice and soy isolate samples had CV values of 53.71% and 66.25%, respectively; however, each sample contained only about 1% TDF. The enzymatic-gravimetric method for determining TDF has been adopted official first action.  相似文献   
14.
Babesia microti-like piroplasms are a recently recognized cause of illness in dogs in northwest Spain. Our objective was to describe the clinical characteristics and investigate the risk factors for azotemia and death among 58 B microti-like infected dogs. Twenty-one of the 58 (36%) dogs were azotemic at the time that the infection was diagnosed. The case fatality rate during the following week was 22%. Dogs with azotemia at the time of diagnosis were 10 times (95% CI, 3.26-28.8) more likely to die during the following week. Azotemia was the main cause of death for B microti-like infected dogs (attributable fraction = 90%). Severe anemia was present in 45 of the 58 (78%) dogs. Azotemic dogs also presented with hyperphosphatemia, hypoalbuminemia, hypercholesterolemia, proteinuria, and high urine protein: creatinine ratios, suggesting a glomerular component to the disease. Age was the only factor significantly associated with the risk of azotemia (P = .042): on average, a 4-year age increase doubled the risk of an infected dog being azotemic. The only factor significantly associated with mortality was azotemia (P = .001). We concluded that B microti-like infection is associated with a high risk of azotemia and mortality.  相似文献   
15.
A fish meal supply shortage is limiting aquaculture development. Currently, plant‐based proteins, such as soya bean meal, are being used as an alternative protein source, despite that such a diet can adversely affect fish, such as by inducing an inflammatory response. A possible solution is to include dietary additives in farm diets to counteract negative effects. One such solution originates from pine bark extracts, which present bioactive properties. In this study, the antioxidant and anti‐inflammatory properties of Pinus radiata bark extracts were evaluated for the first time in a salmonid cell line. This extract chemically demonstrated antioxidant activity through 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH = 58.4 ± 1.1%) and ferric ion reducing antioxidant power (FRAP = 575 ± 17 mgEqFe(II)·g extract?1) assays. Additionally, the extract showed high flavonoid and phenolic compound contents. Up to 100 mg mL?1, the P. radiata extract showed no cytotoxicity in the CHSE‐214 salmonid embryo cell line. Moreover, the antioxidant activity of the extract (50 μg mL?1) was evaluated by a dichlorofluorescein (DCFH) assay in the SHK‐1 salmon cell line challenged with an oxidant stimulus (H2O2), showing 58.9% activity. The extract also protected DNA from oxidative damage, as observed through a comet assay. When assessing anti‐inflammatory properties in an in vitro inflammation model, the extract significantly reduced the relative expression of the pro‐inflammatory cytokines interleukin‐1β (IL‐1β), tumour necrosis factor‐α (TNF‐α) and interleukin‐8 (IL‐8) and of the inducible cyclooxygenase‐2 (COX‐2) enzyme. These results suggest a potential application of P. radiata bark extract in functional foods in aquaculture.  相似文献   
16.
The African citrus psyllid (AfCP), Trioza erytreae (Del Guercio) (Hemiptera, Triozidae), recently has been found in northwestern Iberian Peninsula (Spain and Portugal). The insect is an important citrus pest because it transmits the phloem-limited bacteria Candidatus liberibacter spp., the causal agents of huanglongbing (HLB), the most devastating disease affecting citrus. The bacteria can be acquired by both AfCP nymphs and adults, but only adults can spread the pathogen. HLB has been detected neither in the Iberian Peninsula nor in Madeira and the Canary Islands, where the psyllid was recorded more than a decade ago. In the latter European islands, the eradication programmes of AfCP failed. Chemical-based control strategies are costly, could trigger increases of other pests and may have negative impact on the environment. The adoption of rigorous quarantine measures is extremely important for areas free of the psyllid. These measures likely represent the most effective prevention strategies for psyllid containment, because the geographic expansion of psyllids in citrus is mainly due to human activities, especially by the transport of plants and freshly harvested fruits from infested to uninfested areas. Many natural enemies may contribute to the reduction of its populations and consequent spread; hence, conservation biological control should be emphasised, especially in areas where the psyllid is not abundant. Classical biological control programmes should also be implemented in HLB-free areas by introducing effective AfCP parasitoids. In areas where HLB is detected, biological control is difficult to apply, and a rigorous chemical control program targeting the psyllid could complement this strategy. This report is an updated review of AfCP and strategies for its control in anticipation of its possible further spread in Europe and the Mediterranean Basin.  相似文献   
17.
Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.  相似文献   
18.
Phosphorus (P) fertilizers are usually supplied prior to or at planting of potato even though most P is taken up 40 to 80 d after emergence. This may lead to inefficient P use as a result of P leaching or fixation in the soil. This study evaluates the effects of split P application at multiple times during the growth period according to the plant's need for P. Potato (Solanum tuberosum L. cv. Ditta) was grown in pots in climate chambers, and radioactive 32P isotope was used to distinguish between the fertilizer and soil‐derived P sources. Two soils were tested in combination with five application rates of P, and the plants were harvested at four dates. The results show that the recovery of P fertilizer can be significantly enhanced if the P supply is split. The result also showed that the proportion of soil‐derived P, accumulated in the plant, was significantly reduced both when more fertilizer P was applied to the soil and when P supply was split into several applications. The positive effects of multiple P applications on the P recovery were greatest in the soil with low P status and low buffer capacity.  相似文献   
19.
Rhodococcus equi is a soil borne bacterium that causes severe morbidity and death in young foals. The economic costs of the disease include loss of life, treatment expenses, veterinary monitoring expenses and, perhaps most importantly, potential reduction in future athletic performance in horses that suffer severe lung abscessations caused by R. equi. Current standard of care for pneumonia caused by R. equi is treatment with a macrolide antimicrobial and rifampicin. However, the hallmark of pneumonia caused by R. equi is severe formation of pyogranulomas and a walling off effect that can prevent systemic antibiotics from reaching antimicrobial concentrations in lung tissues. It is hypothesized that streptolysin O (SLO) used as an adjunct therapy with antibiotics will reduce the duration and severity of disease caused by R. equi pneumonia compared to antibiotic therapy alone. Addition of SLO to the antibiotic enhanced clinical responses compared to the other groups, including the antibiotic alone group. Of particular significance were lower bacterial counts in the lungs and longer survival time in those foals treated with SLO and antibiotics.  相似文献   
20.
Abstract

Foliar application of phosphorus (P) may be a supplementary treatment to sustain adequate P-status of potato (Solanum tuberosum L.). However, the prediction of the potential benefits of foliar P supply is difficult, since several factors, such as weather conditions and plant P-status influence the effects. We determined the impact of soil moisture and soil P-supply on the responsiveness to foliar P-application under controlled environmental conditions. Plant dry matter yields, P-accumulation and phosphorus use efficiency (PUE) with or without foliar application were determined at five soil P-levels in combination with two soil moisture levels. The results suggest that water status is of importance for the responsiveness to foliar P-application and may be related to diffusion of P through the leaf cells, which require a good water status. The PUE was significantly improved with irrigation while adding P to the soil decreased the PUE.  相似文献   
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