The ecoresponsive genome of Daphnia pulex     

Colbourne JK  Pfrender ME  Gilbert D  Thomas WK  Tucker A  Oakley TH  Tokishita S  Aerts A  Arnold GJ  Basu MK  Bauer DJ  Cáceres CE  Carmel L  Casola C  Choi JH  Detter JC  Dong Q  Dusheyko S  Eads BD  Fröhlich T  Geiler-Samerotte KA  Gerlach D  Hatcher P  Jogdeo S  Krijgsveld J  Kriventseva EV  Kültz D  Laforsch C  Lindquist E  Lopez J  Manak JR  Muller J  Pangilinan J  Patwardhan RP  Pitluck S  Pritham EJ  Rechtsteiner A  Rho M  Rogozin IB  Sakarya O  Salamov A  Schaack S  Shapiro H  Shiga Y  Skalitzky C  Smith Z  Souvorov A  Sung W 《Science (New York, N.Y.)》2011,331(6017):555-561

We describe the draft genome of the microcrustacean Daphnia pulex, which is only 200 megabases and contains at least 30,907 genes. The high gene count is a consequence of an elevated rate of gene duplication resulting in tandem gene clusters. More than a third of Daphnia's genes have no detectable homologs in any other available proteome, and the most amplified gene families are specific to the Daphnia lineage. The coexpansion of gene families interacting within metabolic pathways suggests that the maintenance of duplicated genes is not random, and the analysis of gene expression under different environmental conditions reveals that numerous paralogs acquire divergent expression patterns soon after duplication. Daphnia-specific genes, including many additional loci within sequenced regions that are otherwise devoid of annotations, are the most responsive genes to ecological challenges.  相似文献   

Management, breeding, and health records from a captive colony of pekin robins (Leiothrix lutea), 2001 - 2010     

da Cruz CE  de Oliveira LG  Boabaid FM  Zimermann FC  Stein G  Marks F  Cerva C  Lieberknecht C  Canal CW  Driemeier D 《Journal of zoo and wildlife medicine》2011,42(3):451-459

Pekin robins (Leiothrix lutea) were once the most widely kept softbills in captivity. As a result of the Convention on the International Trade of Endangered Species of Fauna and Flora (CITES-1997), the worldwide trade of wild-caught pekin robins has been prohibited due to the depletion of native populations of this species. In Brazil, as in other countries, pekin robins imported prior to the enactment of the CITES have disappeared from aviaries because the end of the birds' natural life span has passed, and only very few captive-bred pekin robins now exist. While captive propagation fails to address the primary causes of wild bird population decline, it might help the recovery of populations of this species. This article presents records made over a 10-yr period of a captive colony of pekin robins. Emphasis is placed on the management of the flock, the ailments affecting the birds, and the findings associated with bird losses. The main causes of bird losses included rearing management failures and age-related disorders.  相似文献   

Influence of urease and nitrification inhibitors on N losses from soils fertilized with urea   总被引：10，自引：0，他引：10  

Paola Gioacchini  Anna Nastri  Claudio Marzadori  Camilla Giovannini  Livia Vittori Antisari  Carlo Gessa 《Biology and Fertility of Soils》2002,36(2):129-135

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Botanical origin and chemical composition of Brazilian propolis   总被引：11，自引：0，他引：11  

Park YK  Alencar SM  Aguiar CL 《Journal of agricultural and food chemistry》2002,50(9):2502-2506

Brazilian propolis has been classified into 12 groups based on physicochemical characteristics: five in the southern Brazil group (group 3), one in the southeastern Brazil group (group 12), and six in the northeastern Brazil group (group 6). The plant origins of these groups were investigated using reversed-phase high-performance thin-layer chromatography (RPHPTLC), reversed-phase high-performance liquid chromatography (RPHPLC), and gas chromatography-mass spectrometry (GC-MS). It was concluded that the origins of propolis group 3, group 6, and group 12 are resins of the poplar tree, Hyptis divaricata, and Baccharis dracunculifolia, respectively.  相似文献   

Model studies on the photosensitized isomerization of bixin     

Montenegro MA  Rios Ade O  Mercadante AZ  Nazareno MA  Borsarelli CD 《Journal of agricultural and food chemistry》2004,52(2):367-373

The photosensitized isomerization reaction of the natural cis carotenoid bixin (methyl hydrogen 9'-cis-6, 6'-diapocarotene-6, 6'-dioate) with rose bengal or methylene blue as the sensitizer in acetonitrile/methanol (1:1) solution was studied using UV-vis spectroscopy, high-performance liquid chromatography (HPLC), and time-resolved spectroscopic techniques, such as laser-flash photolysis and singlet oxygen phosphorescence detection. In both N(2)- and air-saturated solutions, the main product formed was all-trans-bixin. The observed isomerization rate constants, k(obs), decreased in the presence of air or with increase in the bixin concentration, suggesting the participation of the excited triplet state of bixin, (3)Bix, as precursor of the cis--> trans process. On the other hand, bixin solutions in the absence of sensitizer and/or light did not degrade, indicating that the ground state of bixin is stable to thermal isomerization at room temperature. Time-resolved spectroscopic experiments confirmed the formation of the excited triplet state of bixin and its deactivation by ground state bixin and molecular oxygen quenching processes. The primary isomerization products only degraded in the presence of air and under prolonged illumination conditions, probably due to the formation of oxidation products by reaction with singlet molecular oxygen. An energy-transfer mechanism was used to explain the observed results for the bixin transformations, and the consequences for food color are discussed.  相似文献   

Palaeoenvironmental Reconstruction of Lago Di Albano (Central Italy) during the Late Pleistocene Using Fossil Ostracod Assemblages     

Claudio A. Belis 《Water, air, and soil pollution》1997,99(1-4):593-600

A fine resolution study on fossil ostracods in late glacial sediments from Lago di Albano was performed within the framework of the European project PALICLAS. Four cores from two coring sites were analysed. At Site 1, located at 70 m depth, cores PALB94 1E and PALB94 1C were collected, while cores PALB94 6A and PALB94 6B were collected at Site 6 at 30 m depth. The autoecology of the ostracod species, cluster analysis, PCA and CA ordination numerical analyses were performed in order to identify changes in environmental conditions within the sedimentary record. Three assemblages were recognized: (a) dominated byC. neglecta representing sublittoral environments, (b) dominated byC. neglecta accompanied byPotamocypris spp. related to spring influx and (c) dominated byCyclocypris sp. associated with littoral and relatively warmer conditions. A reconstruction of lake water level, oxygen concentration near the bottom and lake productivity , based on ostracod autoecology and supported by fossil pigment data, was accomplished. Sharp fluctuations in water level and productivity seem to indicate climatic oscillations between ca 30 to ca 17 kyr BP.  相似文献   

Coriander essential oil composition from two genotypes grown in different environmental conditions     

Gil A  De La Fuente EB  Lenardis AE  López Pereira M  Suárez SA  Bandoni A  Van Baren C  Di Leo Lira P  Ghersa CM 《Journal of agricultural and food chemistry》2002,50(10):2870-2877

The objective was to study the essential oil composition of coriander fruits in plants growing in environments differing in soil conditions and weediness level. Factorial field experiments were conducted in two locations from the Rolling Pampas, Argentina, and two coriander landraces (European and Argentinean) were tested under two levels of nitrogen fertilization and weediness. Data were evaluated with uni- and multivariate techniques. The variation in the oil composition was related to the relative proportion of the constituents and not to the presence/absence of a particular component. Weather conditions in 1997 favored linalool and camphor in both landraces. Location, fertilization, and weediness also affected the chemical profile. The European landrace showed a more stable concentration of the major components than the Argentinean landrace. These results, which show the relationships between some environmental conditions and the essential oil composition, are useful in the development of innovative strategies aimed to improve oil composition and to manage crop pests.  相似文献   

Land contamination by toxic elements in abandoned mine areas in Italy     

Mohammad Wahsha  Mandana Nadimi-Goki  Claudio Bini 《Journal of Soils and Sediments》2016,16(4):1300-1305

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Evaluation of the antimicrobial activity of citrus essences on Saccharomyces cerevisiae     

Belletti N  Ndagijimana M  Sisto C  Guerzoni ME  Lanciotti R  Gardini F 《Journal of agricultural and food chemistry》2004,52(23):6932-6938

The aim of this research was to assess the antimicrobial activity of nine different industrial essences used in a soft drink factory in relation to their composition, as well as to verify the role of vapor pressure on their bioactivity. The essences were tested against a Saccharomyces cerevisiae strain isolated from spoiled soft drinks. The tests were carried out by adding the essences directly to a liquid medium or into the headspace of closed systems inoculated with the yeast. The headspace composition was evaluated through a solid phase microextraction-gas chromatography technique. The use of a mass spectrometer allowed the identification of the peaks detected. The microbial growth was indirectly monitored by measuring the metabolic CO2 released by the yeast. The results obtained indicated that the most effective essences were characterized by the highest concentration of some terpenes, such as citral, beta-pinene, and p-cymene. Moreover, all of the essences were more bioactive when added directly to the liquid medium.  相似文献   

Direct HPLC analysis of quercetin and trans-resveratrol in red wine,grape, and winemaking byproducts   总被引：1，自引：0，他引：1  

Careri M  Corradini C  Elviri L  Nicoletti I  Zagnoni I 《Journal of agricultural and food chemistry》2003,51(18):5226-5231

A simple and fast reversed-phase HPLC method using diode array detection was developed and validated for the simultaneous determination of trans-resveratrol and quercetin in Sicilian red wine from the Nero d'Avola red grape variety. Investigation was also extended to the quantitative determination of resveratrol and quercetin in grape skins and winemaking byproducts obtained from the same cultivar. Samples were eluted using a C18 narrow-bore column under isocratic conditions in less than 20 min. Quantification of trans-resveratrol and quercetin in red wine was performed without any sample pretreatment, whereas the determination of these phenolic compounds in grape skins and wine pomage required a solvent extraction procedure. Linearity was demonstrated over the 0.39-12.5 and 0.45-57.6 microg/mL range for trans-resveratrol and quercetin, respectively. Detection limits in real samples were in the low ppm level (0.07 mg/L for trans-resveratrol and 0.12 mg/L for quercetin). The HPLC-UV/DAD method was applied for the routine analyses of red wine and grape skin and winemaking byproduct extracts to evaluate their trans-resveratrol and quercetin content. In particular, a very high content of quercetin was found in wine pomace, suggesting the use of this wine byproduct as a potential source of this health-promoting phenolic compound.  相似文献