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261.
The increase of land use for crop cultivation and forest in South Central Chile, and the increasing wildcrafting of medicinal plants has resulted in a significant reduction of the plant population density of many native and endemic medicinal plants. Their cultivation and domestication is very limited, and there are no regulations or legislation for wildcrafting in Chile. The objectives of this study were to collect genetic material from five native medicinal plants (Adesmia emarginata, Buddleja globosa, Fabiana imbricata, Linum chamissonis, and Sophora macrocarpa), characterize the environmental conditions in which these grow in the Bio-Bio Region, Chile, and to determine the content of specific bioactive molecules. A maximum of 10 accessions of each species were collected in 2003, 2004, and 2005 in a longitudinal and transversal transect of the Bio-Bio Region (36°00′-38°30′S; 71°W). Data of altitude, light conditions, soil chemical and physical characteristics and associated flora of the site collection were recorded. Seed germination requirements and the content of specific bioactive molecules (flavonoids or rutin) were also determined. In general, all these species are adapted to grow in poor soils with different pH values, P and K levels, low organic matter and N content. Flavonoids were determined in both A. emarginata (0.6-1%) and B. globosa (9.7-13.9%) leaves, while rutin concentration was determined in F. imbricata leaves and stems (1.3-5.3%). Results showed great variations for the content of active principles with medicinal activity, which indicates a corresponding variation in the quality of raw materials for the pharmaceutical industry. Due to the fact that information on the domestication, propagation, cultivation and agronomic practices can ensure good pharmaceutical quality, this study provides a basis for further research on Chilean medicinal plants.  相似文献   
262.
Developing chipping cultivars with improved tuber quality and disease resistance is a major interest for breeders and the potato industry. A popular chipping cultivar ‘Atlantic’, is desired for its high yield and gravity. However, this cultivar suffers from poor internal tuber quality and high scab susceptibility. On the contrary, cultivar ‘Superior’ is known to have excellent tuber internal quality and moderately scab resistance. In addition, this cultivar is known to have high tuber calcium as compared to ‘Atlantic’. The present study intended to generate populations that can be suitable for the genetic study of tuber calcium, internal quality, common scab, and other commercially important traits such as yield, specific gravity and chip quality at the tetraploid level. Two populations obtained by reciprocally crossing the cultivars ‘Atlantic’ and ‘Superior’ were evaluated during 2009 to 2012 at Hancock, Wisconsin. Significant genotype effects and moderately low to high broad-sense heritabilities were identified for all traits evaluated indicating that the observed phenotypic variation has an important genetic component. In addition, the parents differed significantly for all traits across trials, and most genotypes performed in between the two parents but some genotypes were more extreme than the parents. Furthermore, evidence of reciprocal effects was found for some traits. In addition to learning about the genetics of these important traits we were able to identify some genotypes that combined the commercially desired traits of the two cultivars.  相似文献   
263.
The presence of alkaloids in different species and varieties of Lupin limit their use in the diet [4, 9]. Experiments have been carried out to obtain protein concentrates [3, 4] and isolates [10, 11, 12] of two species of Lupins.L. albus andL. mutabilis and these have been compared with those carried out with soya. The results obtained indicated the importance of this flour, due to its high protein content in relation to the weight of the initial product used. In the protein isolates, with comparable yields of 29%, the protein levels were 90% for the soya and 96% for theL. mutabilis. For the concentrates (65% yield in soya to 72% inL. albus) protein percentages of 52% for the soya, 47% forL. albus and 67% forL. mutabilis, were obtained.  相似文献   
264.
A group of 47 bovine viral diarrhoea virus (BVDV) strains isolated from a variety of bovine tissues from eight different geographical areas of Spain and two BVDV strains isolated from a cell line were characterized antigenically with a panel of 23 monoclonal antibodies (mAbs). The mAbs were directed at one of three viral proteins: E2, Erns and NS2-3. A peroxidase-linked assay was used to test the mAbs for reactivity against infected cell monolayers. The data were analysed by two computational methods: the Antigenic Distance Program (MAP) and the Phylogeny Inference Package (PHYLIP), and compared with those obtained previously using the same mAbs with other pestiviruses, including reference strains and UK field isolates. All the Spanish field strains studied appeared to be broadly similar to reference strains of BVDV and were included in the subgroup of classical BVDV, meanwhile the two strains isolated from a cell line were included in the subgroup of atypical pestiviruses.  相似文献   
265.
This research evaluates the addition of alkaline amendments to enhance the degradation of polylactic acid polymers (PLA) in compost conditions. The use of compostable biopolymers is increasing in part because they are advertised as compostable. However, PLA degrades slowly compared to the organic wastes in compost and even when processed in commercial composting facilities may not fully break down. This results in the accumulation of biopolymers in compost facilities and increased difficulty in identifying and removing contamination from traditional plastics. Alkaline amendments were used to accelerate the degradation of two PLA products in compost conditions. Six flasks containing food scraps, compost inoculant, and an alkaline amendment were set up as bioreactors with half containing clear PLA and the others including opaque PLA. The six bioreactors were incubated for 22 days. The mass loss and final visual inspection, including microscopy, showed increased degradation within the bioreactors containing the alkaline treatments. These results show that the addition of alkaline amendment to composting systems may enable more effective processing of biopolymers, expanding the range and quantity of wastes that can be processes. The enhanced degradation of biopolymers in compost may enable greater diversion rates for institutions and cities by enabling the acceptance of biopolymers and any mixed organics stream which includes biopolymers wastes.  相似文献   
266.
Journal of Soils and Sediments - This study assessed soils from 36 parks and gardens (Vigo City, NW of Spain) where there are different degrees of traffic intensity and activity. The soils were...  相似文献   
267.
Two methods, one to determine ascorbic acid and one to determine lycopene and beta-carotene, in vegetables and fruits by liquid chromatography coupled with mass spectrometry (LC-MS) have been established. The chromatographic separation of the studied compounds and their MS parameters were optimized to improve selectivity and sensitivity. In both methods, separation was carried out with two coupled columns, first a C(18) and then a dC(18), using as mobile phase 70% methanol (0.005% acetic acid) and 30% acetic acid 0.05% for ascorbic acid determination and a mixture of methanol, tetrahydrofuran, and acetonitrile (60:30:10 v/v/v) for carotenoid analysis in isocratic mode. The molecular ion was selected for the quantification in selective ion monitoring (SIM) mode. Ascorbic acid was detected with electrospray ionization probe (ESI) in negative mode, while chemical ionization atmospheric pressure (APCI) in positive mode was used for the target carotenoids. The methodology for ascorbic acid analysis is based on an extraction with polytron using methanol and a mixture of methaphosphoric acid and acetic acid. Extraction of the carotenoids was carried out with tetrahydrofuran/methanol (1:1) (v/v). The proposed methods were applied, after their corresponding validations, to the analysis of four varieties of tomatoes, tomato in tin enriched and dried tomato, and to the analysis of mango and kiwi fruits, to compare the content in these compounds. Moreover, the influence of the process of freezing and the effect that the manipulation/preservation has in the content of ascorbic acid in tomato have also been studied.  相似文献   
268.
Oryzomys couesi cozumelae is an endemic, threatened rodent from Cozumel Island, Mexico. We estimated its genetic diversity and structure by analyzing microsatellite loci in 228 samples from 12 sampling sites widely distributed throughout the island. Unexpected high levels of genetic and allelic diversity were found: a total of 54 alleles, an average of 10.8 alleles per locus, and high heterozygosity values (mean HO = 0.624, HE = 0.690 and HNei = 0.689). These values are higher than those reported for small sized insular mammals, higher than that found in 37 individuals of the mainland O. couesi from southern Mexico (HO = 0.578) that we analyzed for comparative purposes, and similar to those of other mainland small mammal populations. Despite factors that affect Cozumel’s biota, such as exotic predators and competitors, hurricanes, seasonal population fluctuations and anthropogenic activities, no evidence of genetic bottlenecks was found. A significant population structure was observed and a model of isolation-by-distance was supported. Our findings render O. c. cozumelae a high conservation value, not only for its high genetic diversity and structure, but because available data suggests that its population has declined significantly in recent years. Further habitat fragmentation and population isolation could result in a higher genetic structure and loss of genetic diversity. The protection of habitat, the maintenance of habitat connectivity and the removal of introduced competitors and predators are a conservation priority. Acknowledging that the genetic structure of populations has crucial conservation implications, the present genetic information should be taken into account in management plans for the conservation of O. c. cozumelae.  相似文献   
269.
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