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971.
Green coffee is one of health-promoting supplements of the diet, applied in the form of either preparations or enriched food products. Its positive impact is manifested by mitigation of the development of certain tumors, e.g., in the colon and liver, and type 2 diabetes. Many studies proved that chlorogenic acids are the main active substances in green coffee. The bioavailability of these compounds depends among others on their interactions with other components of the diet, mainly proteins. When they are used as food ingredients, their bioavailability is additionally decreased because of the decomposition or interactions with other ingredients during food processing. The undesirable changes may be limited among others by microencapsulation, for example with β-cyclodextrin. In this study, rats were fed the pro-oxidative high fat diet, which was supplemented with chlorogenic acids from green coffee that were used in four forms such as: a purified extract, complexes of chlorogenic acids and β-cyclodextrin, and bread supplemented with either the extract or the β-cyclodextrin inclusion complex. Chlorogenic acids added to bread because of the reduced absorption from the crumb in the small intestine and increased passage to the colon, contributed to the beneficial modification of enzymatic activities of intestinal microbiota. When added directly to the diet, they contributed to the improved antioxidant status in the liver and kidneys, lowered glucose level and increased HDL level. A high ratio of reduced to oxidized glutathione in the liver and a high concentration of antioxidants in the blood serum were observed after administration of chlorogenic acids in the form of inclusion complexes with β-cyclodextrin, indicating that microencapsulation increased their bioaccessibility due to the limited interactions with other components of the diet.  相似文献   
972.
Purpose

The objective of this study was to determine the long-term environmental changes induced by ancient landslide in the mountain fen. Attempts were made to demonstrate the progress of the soil cover restoration process about 200 years after the landslides and associated with changes in vegetation and soil microarthropod biodiversity and occurrence pattern associated with the restoration of soil cover.

Material and methods

The study covered mountain fen of the Caltho-Alnetum in the Babiogórski National Park in Outer Flysch Carpathians, Poland, where ancient landslide deposits are causing disturbance in fen hydrologic regime and over time related to various rate of fen area natural restoration processes. The drill test has been used to assess changes in layering and thickness of the fen soils. The following soil parameters, such as pH and total organic carbon content, were determined at each distinguish layer. The diversity and distribution pattern of soil microarthropods, represented by Collembola, was examined in two parts of the fen: restored and not-restored. The soil parameters, such as pH, electrical conductivity, total exchangeable base, total organic carbon, and nitrogen content, were determined in the soil samples simultaneously. The assessment of the vegetation structure recovery within studied mountain fen after landslide was referred to average parameters of the community completed for other natural mountain fens under the Caltho-Alnetum community. The research results were statistically verified.

Results and discussion

The test drillings showed that landslides change soil layering, site-specific soil properties of mountain fen such as chemistry (the statistically significant differences were noted only in the case of total organic carbon content), vegetation structure, and soil microarthropod communities. By changing site-specific conditions, landslides influence on the biodiversity and peatland ecosystems functioning.

Conclusion

Our results clearly demonstrate that the landslide itself initiated a complex and lengthy process of changes in biological aspects of peatlands including the biodiversity of the underground fauna and plant community. Soil microarthropod communities represented by Collembola can be used as a good indicator of mountain fen restoration process.

  相似文献   
973.
974.
Aeromonas isolates were collected from cultured fish, characterized phenotypically and identified to species using 16S rDNA. The pathogenicity of all isolates was assayed on the basis of haemolytic and proteolytic activity and challenge tests were performed for isolates from healthy fish. A total of 131 Aeromonas isolates were obtained and identified as follows: A. hydrophila (13), A. bestiarum (23), A. salmonicida (motile biogroup) (19), A. caviae (2), A. sobria (18), A. veronii bt. sobria (42), A. jandaei (1), A. encheleia (11) and A. allosaccharophila (2). All isolates of A. hydrophila and A. bestiarum and most isolates of A. salmonicida and A. veronii were classified as pathogenic. Aeromonas hydrophila was isolated only from diseased trout except for one isolate obtained from carp fry. The other potentially pathogenic Aeromonas species were present in diseased as well as healthy fish. The pathogenicity of isolates from healthy fish was correlated with their enzymatic activity and was also tested by challenge experiments. The dominant pathogenic species were A. veronii bt. sobria, A. bestiarum and A. salmonicida in common carp and A. hydrophila in rainbow trout.  相似文献   
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