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The impact of processing on nonenzymatic antioxidant degradation and lipid oxidation leading to off-flavor development in potato flakes during storage was investigated. Lipoxygenase activity measurements in parallel with the analysis of lipid oxidation products (oxylipins) profiles using HPLC showed that the processing conditions used inhibited efficiently enzymatic lipid oxidation. However, nonenzymatic lipid oxidation products were found throughout processing and in fresh potato flakes. Furthermore, these autoxidative processes cannot be inactivated by the main endogenous nonenzymatic antioxidants in potato tubers (ascorbic acid, phenolic compounds and carotenoids), as these antioxidants are degraded during processing. Indeed, leaching and thermal treatments taking place during processing lead to a decrease of about 95%, 82% and 27% in the content of ascorbic acid, phenolic compounds and carotenoids, respectively. Therefore, storage is a critical step to prevent off-flavor development in potato flakes. Specific attention has thus to be paid on the use of efficient exogenous antioxidants as well as on storage conditions.  相似文献   
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Black locust (Robinia pseudoacacia L.) was the first North-American tree species imported to Europe at the beginning of the seventeenth century. It is commonly planted worldwide because of its adaptability to environmental stresses, its valuable wood, easy propagation, frequent and abundant seed production, excellent coppicing, high seedling survival, and relatively high wood yield. In Europe, Romania and Hungary have the most highly-developed black locust growing techniques and experiences. As a result of increasing interest in black locust in many countries, this review aims to provide a comprehensive overview of state-of-the-art site requirements, propagation, improvement and management (including growth and yield as well as use in energy plantations).  相似文献   
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Pesticide use in developing countries increases rapidly. In many regions, we miss knowledge of how frequently pesticides are applied and which active ingredients are used. We present a new cost-efficient and rapid assessment method of recording pesticides diversity in rice-dominated landscapes and present some evidence of the misuse of active ingredients in our study regions. We investigated 17 rice fields in two regions of Northern Vietnam in 2014 and 2015. At each region, we explore the abundance of pesticides used with three methods including (1) the novel approach of collecting pesticide packages close to our target rice fields, (2) observations of farmers spraying pesticides in the surrounding and (3) interviewing local farmers. By collecting pesticide packages, we found 811 packages containing 74 different active ingredients. On average, 19 active ingredients (ranging from four to 40 active ingredients) were applied with an average content of 275.3 g of active ingredients per site. Insecticide packages (39%) were most abundant followed by those of fungicides (31%), herbicides (16%) and other active ingredients (14%). On all sites, active ingredients banned in the European Union were applied by the farmers. Collecting pesticide packages proved to be an efficient and rapidly implemented method to obtain some baseline information about pesticide application (for Northern Vietnam). We suspect that improved agricultural extension services could contribute to good agricultural practices in pest management. Generally, better information and education for local farmers for appropriate use of pesticides seem a necessity.  相似文献   
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Two major human-made problems in rice production systems in the north of Vietnam concern the low plant-available silicon content of soils and the low biodiversity. The results of the LEGATO project suggest a change to an environmentally friendly rice production system that will help to recover biodiversity. We propose here a framework for a demonstration and dissemination model that will be exemplary for the farmers once it has been successfully realized. We advocate local-option models in different districts to demonstrate to farmers. The methods should be adapted to local and ecoregional differences in climate and land-use tradition, and they explicitly take into account soil care, organic fertilizer, manual weeding, native nectar-rich plant bunds, manual pest snail collection, hymenopteran nesting aids, and biodiversity and yield monitoring.  相似文献   
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TerraRossa (POR01PG20–12) is a mid-season specialty potato, released by Oregon State University, and is a product of the Northwest Potato Variety (Tri-State) Development Program. This cultivar is unique among commercially available potato cultivars in that plants produce small- to medium-sized smooth, oblong- to long-shaped tubers with red skin and red flesh. Total tuber yields of TerraRossa are similar to Dark Red Norland and less than Red La Soda. Average tuber size (136 g) is less than both of the comparison cultivars, reflecting inherent differences in tuber size distribution. TerraRossa tubers have total antioxidant levels higher than traditional white fresh varieties and comparable to the All Blue purple potato, known for its high antioxidant levels. Sensory evaluations of TerraRossa tubers indicated that it has good culinary attributes following boiling, baking, and microwaving. Potato chips made from TerraRossa tubers retained their unique red color, which represents a novelty in the chipping industry. TerraRossa could be a good candidate for the organic sector due to its tolerance to common scab (Streptomyces scabies) and tuber late blight (Phytophthora infestans) and its resistance to golden cyst nematode (Globodera rostochiensis). Due to its high yields, high chipping quality, good culinary properties, high antioxidant content and disease resistance, TerraRossa is a good candidate for opening new specialty type markets, adding diversity to the marketplace.  相似文献   
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Swine Hepatitis E virus (HEV) can be transmitted from pigs to humans causing hepatitis. A high prevalence of HEV in wild boar populations is reported for several European countries, but actual data for Germany are missing. During the hunting season from October to December 2007 liver, bile and blood samples were collected from wild boars in four different German regions. The samples were tested for HEV RNA by quantitative PCR (qPCR) and anti-HEV IgG antibodies by two different ELISAs and a Line immunoassay. A seroprevalence of 29.9% using ELISA and 26.2% in the Line immunoassay was determined. The seroprevalence rate varied greatly within the analyzed regions. However, qPCR analysis revealed a higher prevalence of 68.2% positive animals with regional differences. Surprisingly, also adult wild sows and wild boars were highly HEV positive by qPCR. Compared to liver and serum samples, bile samples showed a higher rate of positive qPCR results. Sequencing and phylogenetic analysis of a 969 nt fragment within ORF 2 revealed that all isolates clustered within genotype 3 but differed in the subtype depending on the hunting spot. Isolates clustered within genotypes 3i, 3h, 3f and 3e. Within one population HEV isolates were closely related, but social groups of animals in close proximity might be infected with different subtypes. Two full-length genomes of subtypes 3i and 3e from two different geographic regions were generated. The wild boar is discussed as one of the main sources of human autochthonous infections in Germany.  相似文献   
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The flavonoid pattern of an acetonic extract of Grindelia robusta Nutt. was investigated in detail. The flavonoids were enriched by CC. In addition to twelve known methylated exudate flavonols four compounds were identified for the first time in G. robusta. Several substances of the flavonoid complex, among them the main compounds quercetin-3-methylether and 6-OH-kaempferol-3,6-dimethylether, were tested for their activity to inhibit neutrophil elastase. Quercetin-3-methylether was shown to be most active with an IC50 of 19 µM, thus obviously contributing to the anti-inflammatory activity of the drug.  相似文献   
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