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101.
Opencast coalmine effluent contains higher concentrations of Cd, Cr, Co, Ni and Pb. Biofiltration of these metals has been demonstrated successfully with the help of aquatic macrophytes i.e., E. crassipes, L. minor and A. pinnata. Experiments revealed E. crassipes reduced highest concentration of heavy metals followed by L. minor and A. pinnata on 20th days retention period. Plant tissue analysis revealed higher accumulation of metals in roots than leaves. Highly significant correlations have been noted between removal of heavy metals in effluent and their accumulation in roots and leaves of the experimental sets. Translocation factor also revealed lower transportation of metals from root to leaves. Reduction in chlorophyll and protein content was noted with the accumulation of heavy metals. N, P and K analysis in plant tissues indicated continuous decrease in their concentration with increasing metal concentration. Negative and significant correlations between metal accumulation and N, P and K concentrations in plant tissues showed adverse effects of heavy metals. Analysis of variance (Dunnett t-test) showed significant results (p?<?0.001) for all the metals in different durations. 相似文献
102.
Leontowicz M Gorinstein S Leontowicz H Krzeminski R Lojek A Katrich E Cíz M Martin-Belloso O Soliva-Fortuny R Haruenkit R Trakhtenberg S 《Journal of agricultural and food chemistry》2003,51(19):5780-5785
The aim of this study was to assess the bioactive compounds of apple and pear peel and pulp in vitro and their influence on plasma lipids and antioxidant potentials in vivo. The antioxidant potentials measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), beta-carotene bleaching (beta-carotene), and nitric oxide inhibition radical scavenging (NO) tests in apple peel and pulp were significantly higher than in pear peel and pulp, respectively. The ethanol extract of apple peels showed the strongest inhibition of lipid peroxidation as a function of its concentration and was comparable to the antioxidant activity of butylated hydroxyanisole. The pear pulp extract had the weakest antioxidant ability, whereas other extracts such as apple pulp and pear peel were nearly equal. The antioxidant activities comprised contributions from polyphenols, phenolic acids, and flavonoids and correlated well with polyphenols and flavonoids. The correlation coefficients between polyphenols and antioxidant activities by DPPH, beta-carotene, and NO were as follows: 0.9207, 0.9350, and 0.9453. Contrarily, the correlation coefficient between the content of dietary fiber and the antioxidant activities test was low. The content of all studied indices in apple and pear peel was significantly higher than in peeled fruits (p < 0.05). Diets supplemented with fruit peels exercised a significantly higher positive influence on plasma lipid levels and on plasma antioxidant capacity of rats than diets with fruit pulps. 相似文献
103.
The ability to make a priori assessments of a species' response to fragmentation, based on its distribution in the landscape, would serve as a valuable conservation and management tool. During 1997-1999, we monitored 717 scent stations to examine seasonal use of forest patches, corridors, and crop fields by coyotes (Canis latrans), domestic cats (Felis catus), foxes (Vulpes vulpes and Urocyon cinereoargenteus), raccoons (Procyon lotor), striped skunks (Mephitis mephitis), opossums (Didelphis virginiana), and long-tailed weasels (Mustela frenata). For each species we developed landscape-based ecologically scaled landscape indices (ELSI), and we modeled species spatial distribution across three spatial scales (landscape-level, element-level, and local habitat-level). Our results suggest that these predators view landscape fragmentation at different spatial scales and demonstrate strong interspecific differences in their response to elements of the landscape. All species except coyotes and domestic cats avoided agricultural fields. In general, predator species that were more mobile (i.e. high ESLI for landscape connectivity; coyotes) were characterized by landscape- and element-based logistic models. In contrast, models including local habitat features generally were most appropriate for less mobile or more stenophagous predators (e.g. long-tailed weasels). Our analysis extends the application of the ESLI concept to species assemblages that do not appear to function as metapopulations, and it highlights the importance of examining spatial scale and species-specific responses to habitat fragmentation. We discuss the relevance of these findings for defining ecological landscapes, understanding predator-prey interactions at multiple spatial scales, and conserving predator and prey populations in fragmented landscapes. 相似文献
104.
Choi YH Sertic S Kim HK Wilson EG Michopoulos F Lefeber AW Erkelens C Prat Kricun SD Verpoorte R 《Journal of agricultural and food chemistry》2005,53(4):1237-1245
The metabolomic analysis of 11 Ilex species, I. argentina, I. brasiliensis, I. brevicuspis, I. dumosavar. dumosa, I. dumosa var. guaranina, I. integerrima, I. microdonta, I. paraguariensis var. paraguariensis, I. pseudobuxus, I. taubertiana, and I. theezans, was carried out by NMR spectroscopy and multivariate data analysis. The analysis using principal component analysis and classification of the (1)H NMR spectra showed a clear discrimination of those samples based on the metabolites present in the organic and aqueous fractions. The major metabolites that contribute to the discrimination are arbutin, caffeine, phenylpropanoids, and theobromine. Among those metabolites, arbutin, which has not been reported yet as a constituent of Ilex species, was found to be a biomarker for I. argentina,I. brasiliensis, I. brevicuspis, I. integerrima, I. microdonta, I. pseudobuxus, I. taubertiana, and I. theezans. This reliable method based on the determination of a large number of metabolites makes the chemotaxonomical analysis of Ilex species possible. 相似文献
105.
Elmi Lotze Robert Wilsdorf Sandy Turketti Wojciech Józef Przybyłowicz Jolanta Mesjasz-Przybyłowicz 《Journal of plant nutrition》2015,38(10):1469-1477
Distribution of calcium in the apple has been quantified using mineral analyses of fruit sections during the mid-1900s by various researchers. Most of the work was done either at harvest, or after storage. We used Proton-induced X-ray spectrometry (PIXE) and Scanning Electron Microscopy to correlate Ca distribution in apples to results obtained from mineral analyses (MA). For fruit at harvest transverse distribution of Ca in ‘Braeburn’ apples determined by PIXE confirmed similar analyses with MA. It was not possible to establish a significant relationship between the total Ca concentration determined by PIXE and soluble Ca concentration from MA in this paper, either at harvest, or 80 days after full bloom (dafb). A significant correlation was found between PIXE and SEM results 80 dafb. 相似文献
106.
Based on several years of data from two populations of the endangered Apollo butterfly (Parnassius apollo, L. 1758), we study how the amount and spatial location of patches of larval (host-plant) and adult (nectar plant) resources affects the distribution of females and their larval offspring in the following year. In the coastal population (nectar-plant and host-plant patches spatially segregated), females moved frequently between patches to aggregate on larger host-plant patches close to nectar-plant patches. In the archipelago population (where nectar-plants and host-plants co-occur), the abundance of females increased with higher proximity to other host-plant patches and with more nectar-plants on the patch. Next year’s larval abundance correlated with the abundance of females in the previous season in both populations. A model of the population dynamics in the two populations in relation to the spatial configuration of nectar and host-plant patches showed that the spatial configuration of larval and adult resources had population-dynamical consequences. In many organisms, different life-history stages use different resources. Incorporation of information on the location and abundance of adult resources can provide additional insight for the suitability of a particular landscape in harbouring a population. 相似文献
107.
Intergeneric relationships in the Australian Vitaceae: new evidence from cpDNA analysis 总被引:1,自引:0,他引:1
Maurizio Rossetto Betsy R. Jackes Kirsten D. Scott Robert J. Henry 《Genetic Resources and Crop Evolution》2001,48(3):307-314
Taxa related to important agricultural species are likely to contain a considerable amount of potentially valuable genetic diversity. Nevertheless, before breeding programs or gene discovery projects can be initiated it is important to understand the phylogenetic relationships between the species involved. A component of a major gene discovery project in grapes at the Centre for Plant Conservation Genetics (Southern Cross University, Australia) is directed at the discovery of novel genes in native Vitaceae. As a result a study was conducted in order to assess the phylogenetic relationships between V. vinifera and the native members of the three major Australian genera: Cayratia, Cissus and Tetrastigma. CpDNA sequence analysis (from the trnL intron) adequately resolved intergeneric relationship between the majority of the species studied and provided some useful new information on the phylogenetic relationships within the Vitaceae. This preliminary project identified two species, C. hypoglauca and C. sterculiifolia, as being closely related to V. vinifera and worthy of further in-depth investigation. 相似文献
108.
Robert McDonald Meghan McKnight Elizabeth Selig Christy Violin 《Biological conservation》2005,126(1):24-40
The concept of an ecoregion, a discrete spatial area where species composition is presumed to be relatively homogeneous compared to that between areas, has become an increasingly common conservation tool. We test the effectiveness of one ecoregion delineation (World Wildlife Fund) in capturing patterns of change in species composition of birds, mammals, and trees across the United States (excluding Hawaii) and Canada, and describe the extent to which each ecoregion boundary is concurrent with relatively large changes in species composition. Digitized range maps were used to record presence/absence in 50 × 50 km equal-area grid cells covering the study area. Jaccard’s index of similarity was calculated for all pairs of cells in the same or adjacent ecoregions. The average rate at which similarity declined with geographic distance was calculated using pairs of cells within the same ecoregion (intra-ecoregion turnover) or using pairs of cells in adjacent ecoregions (inter-ecoregion turnover). The intra-ecoregion rate varies widely among ecoregions and between taxa, with trees having a faster rate of similarity decline than mammals or birds. For all three species groups, most ecoregion boundaries have similar rates across them (inter-ecoregion) than that within each adjacent ecoregion (intra-ecoregion), with the exception of zones of transition between biomes and major geographical features. Although the ecoregion concept is useful for many other conservation applications, the lack of systematic, high turnover rates along ecoregion boundaries suggests that ecoregions should not be used as a quantitative basis for delineating geographic areas of a particular taxonomic group. 相似文献
109.
Besombes S Robert D Utille JP Taravel FR Mazeau K 《Journal of agricultural and food chemistry》2003,51(1):34-42
As a new approach for the study of the ultrastructure of lignin, the conformational preferences of lignin beta-O-4 model compounds have been investigated by molecular modeling. The computed results have been compared with the experimental data (X-ray crystal structures and (3)J(H)(alpha)(H)(beta) NMR coupling constant values) reported in the literature. This comparison has led to an improved understanding of the influence of the structure, stereochemistry, and intramolecular H-bonding upon the conformational properties of the beta-O-4 dimers. A large number of low-energy conformations have been predicted for the structures. It has also appeared that the conformational features are predominantly governed by local steric interactions rather than by differences in the H-bonding interactions. The threo and erythro forms differ significantly in their conformational features, with a preferential extended overall shape for the threo form in which the bulky aromatic groups are distant from each other. 相似文献
110.
New prenylated benzoic acid and other constituents from almond hulls (Prunus amygdalus Batsch). 总被引:2,自引:0,他引:2
Shengmin Sang Karen Lapsley Robert T Rosen Chi-Tang Ho 《Journal of agricultural and food chemistry》2002,50(3):607-609
One new prenylated benzoic acid derivative, 3-prenyl-4-O-beta-D-glucopyranosyloxy-4-hydroxylbenzoic acid, and three known constituents, catechin, protocatechuic acid, and ursolic acid, have been isolated from the hulls of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the new prenylated benzoic acid derivative were accomplished on the basis of high-resolution 1D and 2D nuclear magnetic resonance data. All of these compounds except ursolic acid are being reported from almond hulls (P. amygdalus) for the first time. 相似文献