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81.
Olive mill waste is a potential source for the recovery of phytochemicals with a wide array of biological activities. Phytochemical screening of hexane, methanol, and water extracts revealed a diversity of compounds, perhaps overlooked in previous studies through intensive cleanup procedures. Methanol and water extracts contained large amounts of biophenols, and further testing of polar extraction solvents, including ethyl acetate, ethanol, propanol, acetone, acetonitrile, and water/methanol mixtures, highlighted the latter as the solvent of choice for extraction of the widest array of phenolic compounds. Stabilization of the resulting extract was best achieved by addition of 2% (w/w) sodium metabisulfite. Quantitative data are reported for nine biophenols extracted using 60% (v/v) methanol in water with 2% (w/w) sodium metabisulfite. Six compounds had recoveries of greater than 1 g/kg of freeze-dried waste: hydroxytyrosol glucoside, hydroxytyrosol, tyrosol, verbascoside, and a derivative of oleuropein.  相似文献   
82.
Biophenols have attracted increasing attention during the past few years due to their biological activities and natural abundance and are potential targets for the food and pharmaceutical industries. Olive mill waste (OMW) is rich in biophenols and typically contains 98% of the total phenols in the olive fruit, making value addition to OMW an attractive enterprise. The phenolic profile of OMW is complex, yet this complexity has not been fully exploited in the valorization of the waste. Most work on the bioactivity of OMW has focused on antioxidant and antimicrobial activities. The analytical techniques used to identify and quantify active biophenols are also reviewed.  相似文献   
83.
There are substantial environmental and economic benefits to be gained by recycling spent mushroom substrate (SMS). Researchers throughout the world have grown many types of crops with SMS but information with ornamental nursery crops is sparse. High salt levels in SMS is largely responsible for its restricted use in agriculture. Investigations showed that many ornamental woody species grew well in 6-liter (2-gal) regular nursery containers amended with different proportions of SMS (33%, 67%, and 100% by volume) mixed with bark. Test species were: cotoneaster (Cotoneaster dammeri ‘Coral Beauty’); deutzia (Deutzia gracilis); dogwood (Cornus alba and C. alba ‘Argenteo-marginata’); forsythia (Forsythia × intermedia ‘Lynwood’); juniper (Juniperus sabina ‘Blue Danube’ and J. virginiana ‘Hetzii’); ninebark (Physocarpus opulifolius); potentilla (Potentilla fructicosa ‘Red Ace’); privet (Ligustrum vulgare); rose (Rosa ‘John Franklin’); and weigela (Weigela ‘Bristol Ruby’ and W. florida ‘Variegata Nana’). Despite variable species response, there was little relationship of growth performance to: source of SMS (different farms, fresh or aged, leached or unleached); initial or subsequent salt levels in the media; chemical or physical characteristics of the media, including increasing shrinkage with increasing amounts of SMS; or contents of leaf nutrients. Plants of all species, except privet, achieved marketable size and quality at harvest. Time-course studies demonstrated that rapid leaching of undesirable high salt levels from the containers was the key to our successful results. In further studies which evaluated a wider range of amendment combinations (peat, bark, and sand) with SMS included in amounts (25% or 50%) more desirable in commercial container nursery practice, all SMS amended media promoted excellent growth of nursery crops. Minimal shrinkage was obtained with a medium consisting of 25% sand, 25% SMS, and 50% peat or bark.  相似文献   
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Two sizes of excised microcosms (15 and 30 cm in diameter) and 30 cm diameter homogenized microcosms were compared with field plots to assess the transport of As in a grassland ecosystem. The purpose of the experiment was to determine the suitability of using microcosms for measuring the transport of toxic substances through grassland ecosystem components (soil, grass, and soil water). Arsenic was applied to each set of microcosms and the field plots, at rates of 0, 0.5, and 5.0 mg cm?2. Results show that As was highly assimilated by grass, with the greatest concentration being 720 ppm. The microcosms were found to represent the field plots in terms of As transport, and offer several advantages over field testing of toxic substances.  相似文献   
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Background

Molecular profiling of gene families is a versatile tool to study diversity between individual genomes in sexual crosses and germplasm. Nucleotide binding site (NBS) profiling, in particular, targets conserved nucleotide binding site-encoding sequences of resistance gene analogs (RGAs), and is widely used to identify molecular markers for disease resistance (R) genes.

Results

In this study, we used NBS profiling to identify genome-wide locations of RGA clusters in the genome of potato clone RH. Positions of RGAs in the potato RH and DM genomes that were generated using profiling and genome sequencing, respectively, were compared. Largely overlapping results, but also interesting discrepancies, were found. Due to the clustering of RGAs, several parts of the genome are overexposed while others remain underexposed using NBS profiling. It is shown how the profiling of other gene families, i.e. protein kinases and different protein domain-coding sequences (i.e., TIR), can be used to achieve a better marker distribution. The power of profiling techniques is further illustrated using RGA cluster-directed profiling in a population of Solanum berthaultii. Multiple different paralogous RGAs within the Rpi-ber cluster could be genetically distinguished. Finally, an adaptation of the profiling protocol was made that allowed the parallel sequencing of profiling fragments using next generation sequencing. The types of RGAs that were tagged in this next-generation profiling approach largely overlapped with classical gel-based profiling. As a potential application of next-generation profiling, we showed how the R gene family associated with late blight resistance in the SH*RH population could be identified using a bulked segregant approach.

Conclusions

In this study, we provide a comprehensive overview of previously described and novel profiling primers and their genomic targets in potato through genetic mapping and comparative genomics. Furthermore, it is shown how genome-wide or fine mapping can be pursued by choosing different sets of profiling primers. A protocol for next-generation profiling is provided and will form the basis for novel applications. Using the current overview of genomic targets, a rational choice can be made for profiling primers to be employed.
  相似文献   
88.
Context

Functional connectivity is vital for plant species dispersal, but little is known about how habitat loss and the presence of green infrastructure interact to affect both functional and structural connectivity, and the impacts of each on species groups.

Objectives

We investigate how changes in the spatial configuration of species-rich grasslands and related green infrastructure such as road verges, hedgerows and forest borders in three European countries have influenced landscape connectivity, and the effects on grassland plant biodiversity.

Methods

We mapped past and present land use for 36 landscapes in Belgium, Germany and Sweden, to estimate connectivity based on simple habitat spatial configuration (structural connectivity) and accounting for effective dispersal and establishment (functional connectivity) around focal grasslands. We used the resulting measures of landscape change to interpret patterns in plant communities.

Results

Increased presence of landscape connecting elements could not compensate for large scale losses of grassland area resulting in substantial declines in structural and functional connectivity. Generalist species were negatively affected by connectivity, and responded most strongly to structural connectivity, while functional connectivity determined the occurrence of grassland specialists in focal grasslands. Restored patches had more generalist species, and a lower density of grassland specialist species than ancient patches.

Conclusions

Protecting both species rich grasslands and dispersal pathways within landscapes is essential for maintaining grassland biodiversity. Our results show that increases in green infrastructure have not been sufficient to offset loss of semi-natural habitat, and that landscape links must be functionally effective in order to contribute to grassland diversity.

  相似文献   
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Abstract— A chronic, severely pruritic, seborrhoeic skin disorder of West Highland White terriers is reported. The dermatosis has no apparent sex predilection, often begins in animals less than one year of age and is probably genetically programmed. This syndrome is characteristically refractory to standard therapeutic regimens. Histologically the dermatosis is characterized by variable degrees of hyperplastic superficial perivascular dermatitis with a keratinization defect, epidermal dysplasia and the presence of budding yeast in surface and follicular keratin. Malassezia pachydermatis is isolated in pure culture from the skin lesions. Because of the unique histological findings in this syndrome, we propose that the disorder be called “epidermal dysplasia and Malassezia pachydermatis infection in the West Highland White terrier”. Résumé— Une affection cutanée chronique, sévèrement, prurigineuse, séborrhéique, est décrite chez des West Highland White terriers. La dermatose, sans prédisposition apparente de sexe, débute souvent sur des animaux agés de moins d'un an et reconnait probablement une origine héréditaire. La caractéristique de ce syndrome est d'étre résistant aux thérapeutiques habituelles. A l'histologie, la dermatose est caractérisée par des degrés variables de dermatite hyperplasique superficielle périvasculaire avec un défaut de kératinisation une dysplasie épidermique et la présence de levures bourgeonnantes dans la kératine superficielle et folliculaire. Malassezia pachydermatis est isolée en culture pure à partir des lésions cutanées. En raison de l'aspect histologique univoque dans ce syndrome, nous proposons que cette affection soit appelée: “Dysplasie épidermique et infection àMalassezia pachydermatis du West Highland White terrier”. Zusammenfassung— Eine chronische, hochgradig pruriginÖse, seborrhoische Hauterkrankung des Westhighland-White-Terriers wird beschrieben. Die Dermatose zeigt keine deutliche Geschlechtsdisposition, beginnt oft im Alter unter einem Jahr und ist wahrscheinlich genetisch bedingt. Dieses Syndrom spricht auf die üblichen therapeatischen Maßnahmen nicht an (Diagnostik durch Biopsie). Histologisch ist diese Dermatose gekennzeichnet durch unterschiedliche Grade einer hyperplastischen, superfiziellen, perivaskulären Dermatitis mit Keratinisierungsdefekt, durch epidermale Dysplasie und die Anwesenheit von Sproßpilzen (Hefen) im oberflächlichen und follikulären Keratin. Aus den Hautveränderungen wird Malassezia pachydermatis in Reinkultur isoliert. Wegen der einzigartigen histologischen Befunde bei diesem Syndrom schlagen wir vor, diese Erkrankung “Epidermale Dysplasie und Malassezia pachydermatis—Infektion beim Westhighland-White-Terrier” zu nennen.  相似文献   
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