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Apples represent a major dietary source of antioxidative polyphenols. Their metabolic conversion by the gut microflora might generate products that protect the intestine against oxidative damage. We studied the antioxidant effectiveness of supernatants of fermented apple juice extracts (F-AEs, 6 and 24 h fermentation) and of selected phenolic degradation products, identified by HPLC-DAD-ESI-MS. Cell free antioxidant capacity of unfermented apple juice extracts (AEs) was decreased after fermentation by 30-50%. In the human colon carcinoma cell line Caco-2, F-AEs (containing <0.5% of original AE-phenolics) decreased the reactive oxygen species (ROS) level more efficiently than the F-blank (fermented without AE) but were less effective than the respective AEs. Similarly, antioxidant effectiveness of individual degradation products was lower compared to respective AE constituents. Glutathione level was slightly increased and oxidative DNA damage slightly decreased by fermented AE03, rich in quercetin glycosides. In conclusion, F-AEs/degradation products exhibit antioxidant activity in colon cells but to a lesser extent than the respective unfermented AEs/constituents.  相似文献   
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Journal of Plant Diseases and Protection - Psyllids are small, phloem-feeding insects. Several species are vectors of economically important pathogens, such as ‘Candidatus Liberibacter...  相似文献   
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以厨余和杂草废弃物混合物为发酵底物进行了批式和两相厌氧发酵试验。经过25 d的批式厌氧消化后,污染负荷(以挥发固体(VS)质量浓度计)为6.5、12.5、16.0和20.0 g/L的沼气产率分别为1 012、863、879和467mL/g,甲烷产率分别为595、442、440和316 mL/g,其中接种污泥对沼气产率和甲烷产率的贡献分别是304和170mL/g。试验结果表明:污染负荷为6.5 g/L时达到最大产气效率,80%的气体在反应的前8 d产生;污染负荷为12.5和16.0 g/L的产气率在统计学上无显著差别;污染负荷在20.0 g/L时出现产甲烷抑制,甲烷体积分数在反应的前2 d为20%左右。两相发酵试验采用厌氧固体床反应系统,包括4个1 L的固体床反应器和1个2.2 L的厌氧批式反应器。经过12 d的消化,沼气和甲烷产率分别为530和351 mL/g,系统总固体(TS)和VS去除率分别为78%和82%。与批式消化比较,该两相系统污染负荷高,产气稳定,周期短,是处理该类型有机废弃物的有效方法。  相似文献   
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Reference values for Cortisol, T4 and T-Uptake, determined with the Fluorescence-Polarization-Immunoassays (FPIAs) in blood-plasma of different horse groups were established. The highest Cortisol values were measured in blood samples from thoroughbred racehorses and riding horses taken between 7 and 8 a.m. (181 +/- 37 and 268 +/- 43 nmol/l), the lowest gained between 5 and 6 p.m. (69 +/- 45 and 85 +/- 32 nmol/l respectively). Peak values for T4 in riding horses were found in blood samples collected between 1 and 2 p.m. (28.2 +/- 5.7 nmol/l) followed by the samples taken at 5-6 p.m. and 7-8 a.m. T-Uptake values did not show a diurnal variation. Values of thoroughbred racehorses were much lower than in thoroughbred broodmares and riding horses (0.11 +/- 0.03, 0.18 +/- 0.03 and 0.24 +/- 0.05 units). The blood samples collected on 5 successive days showed significant variations for Cortisol. T4-values were stable whilst T-Uptake had small variations.  相似文献   
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Morphological structures of the bovine Papilla mammae can be differentiated with portable ultrasound units and 5 MHz linear arrays. For practical use it is possible to scan the teat in a water-filled plastic cup as a kind of water delay system. The visualization of pathological findings shows a possibility to evaluate this method as a diagnostic tool for the bovine teat.  相似文献   
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Farmland bird declines in Europe are well documented. In the UK, agri-environment schemes are key mechanisms for reversing the declines of birds and other farmland biodiversity, but recent reviews suggest that wet habitats might be a gap in provision by these schemes. Important resources provided by wet habitats include: (i) damp soil, for probing species; (ii) permanent water to provide water-dependent invertebrates, as a source of food; (iii) bare or sparsely vegetated ground in the draw-down zone, to improve access to food; (iv) rank emergent vegetation for nesting. However, wet habitats have been lost from farmland as a result of loss of ponds and filling of ditches, as well as the effective removal of water from fields by surface run-off, itself affected by soil compaction, and extensive under-field drainage. The efficient removal of water from fields can cause problems downstream, both through flooding, and diffuse pollution. Regular farmland pollutants include pesticides, nitrogen, phosphorus and sediment, leading to environmental problems such as eutrophication and reduced quality of drinking water. Major new political instruments, such as the Water Framework Directive, will aim to reduce the impact of this diffuse pollution from agriculture. A variety of solutions to diffuse pollution, such as conservation tillage, buffer strips at field edges, and small constructed wetlands, could simultaneously provide some of the resources required by farmland birds. We suggest that future agri-environment schemes, to be truly multifunctional, could focus on bringing these diverse objectives together.  相似文献   
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This study was undertaken to investigate the feasibility of using Paecilomyces lilacinus NRRL 13 866, chitin, and cellulose amendments, in order to reduce survival and prevent germination of sclerotia from Aspergillus flavus NRRL 6556, NRRL 13 048, and A. parasiticus NRRL 13 005, NRRL 13 539 buried in sandy soil in Georgia and Illinois (April–October, 1990). The number of sclerotia that germinated sporogenically in moist chambers following burial in Illinois was twice that of sclerotia buried in Georgia and varied among the four sclerotium-producing Aspergillus spp. strains. Sclerotium viability, as measured by Aspergillus spp. colony formation on potato dextrose agar, was high (>84%) for all strains and treatments (e.g. amendment, location). Even so, A. parasiticus NRRL 13 539 sclerotia were apparently more susceptible to P. lilacinus colonization than sclerotia from other strains. Treatment with Paecilomyces sp. caused a small but significant reduction in germination among sclerotia buried in Georgia.  相似文献   
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