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131.
Felipe de Oliveira Fernandes Sérgio Ricardo de Oliveira Vitor Klein Marcella Araújo do Amaral Carneiro Pio Colepicolo Eliane Marinho-Soriano 《Journal of applied phycology》2017,29(2):695-705
The genus Gracilaria is one of the most important sources of agar in the world. In Brazil, Gracilaria birdiae is the main commercially exploited species; however, overexploitation has contributed to the depletion of natural beds. In order to obtain more information so as to consolidate G. birdiae cultivation, studies under laboratory (indoor and outdoor) and field (sea and shrimp pond) conditions were conducted to evaluate the effects of fertilizer pulses on biomass and relative growth rate (RGR) of this species. The following nutrient sources used were (T1) shrimp-pond effluent, (T2) fertilizer for aquarium plants (Mbreda), and (T3) fertilizer extract of Ascophyllum nodosum (Acadian). Significant differences for growth were recorded over time for all treatments in both outdoor and field conditions (p < 0.001). The highest RGRs were recorded for treatments that used pulses of commercial fertilizers (T2 and T3) and the lowest for treatment using shrimp-pond effluent pulses (T1). The analysis of the nutrient content in tissue also showed a relationship between growth and nitrogen and phosphorus accumulation in the algal tissues. The N/P ratio indicated a significant effect on the growth of G. birdiae and the highest RGRs were registered for seedlings with a N/P ratio ≥16 (T2 and T3). In conclusion, the best results were recorded for the Mbreda and Acadian commercial fertilizers. However, although no significant differences were detected between growth and the two fertilizers (T2 and T3), the seedlings cultivated under Acadian pulses showed a better performance against environmental stress caused by reduced salinity. 相似文献
132.
133.
Pradier Céline Hinsinger Philippe Laclau Jean-Paul Bouillet Jean-Pierre Guerrini Irae Amaral Gonçalves José Leonardo Moraes Asensio Verónica Abreu-Junior Cassio H. Jourdan Christophe 《Plant and Soil》2017,414(1-2):339-354
Plant and Soil - Comparing root functioning under contrasting rainfall regimes can help assessing the capacity of plant species to cope with more intense and frequent drought predicted under... 相似文献
134.
Daniel D. R. Arcanjo Ana Carolina Mafud Andreanne G. Vasconcelos José Couras da Silva-Filho Maurício P. M. Amaral Lucas M. Brito Marcelo P. Bemquerer Selma A. S. Kückelhaus Alexandra Plácido Cristina Delerue-Matos Nuno Vale Yvonne P. Mascarenhas Fernando Aécio A. Carvalho Aldeidia P. Oliveira José Roberto Souza Almeida Leite 《International journal of peptide research and therapeutics》2017,23(3):323-331
BPP-BrachyNH2 is a proline-rich oligopeptide (PRO) firstly identified in skin secretion of the frog Brachycephalus ephippium, which possess in vitro inhibitory activity of angiotensin-I converting enzyme (ACE) and endothelium-dependent vasorelaxant activity. Considering its potential application in the treatment of cardiovascular diseases, the present work assessed the toxicological profile of the BPP-BrachyNH2. The in silico toxicity prediction was performed from the best model obtained through the optimization of the FASTA query peptide. This prediction study revealed that BPP-BrachyNH2 induced high predicted LD50 values for both humans and rats, and then is well-tolerated in the recommended range. The MTT assay was applied for the in vitro cytotoxic evaluation in murine macrophages. In this assay, a decrease of cell viability was not observed. The in vivo acute toxicological study was performed after the intraperitoneal administration of BPP-BrachyNH2 at doses of 5 and 50 mg/kg. After intraperitoneal administration, no death, alterations in behavioral parameters or weight gain curve was observed, as well as none in the serum biochemical parameters, and gross pathological and histopathological analyses. These observations demonstrates an acceptable safety profile for BPP-BrachyNH2, leading towards further studies focused on investigation of pharmacological and therapeutical applications for this peptide. 相似文献
135.
Alkmim Aline R. da Costa Paula R. Moser Priscila B. Neta Luzia S. França Santiago Vânia M. J. Cerqueira Ana. C. Reis Beatriz G. Amaral Míriam C. S. 《Bioprocess and biosystems engineering》2017,40(12):1839-1850
Bioprocess and Biosystems Engineering - This study aims to evaluate membrane bioreactor (MBR) performance in a pilot scale to treat petroleum refinery effluent, and has been primarily focused on... 相似文献
136.
Comparative mitochondrial and chloroplast genomics of a genetically distinct form of Sargassum contributing to recent “Golden Tides” in the Western Atlantic 下载免费PDF全文
Linda A. Amaral‐Zettler Nicholas B. Dragone Jeffrey Schell Beth Slikas Leslie G. Murphy Clare E. Morrall Erik R. Zettler 《Ecology and evolution》2017,7(2):516-525
Over the past 5 years, massive accumulations of holopelagic species of the brown macroalga Sargassum in coastal areas of the Caribbean have created “golden tides” that threaten local biodiversity and trigger economic losses associated with beach deterioration and impact on fisheries and tourism. In 2015, the first report identifying the cause of these extreme events implicated a rare form of the holopelagic species Sargassum natans (form VIII). However, since the first mention of S. natans VIII in the 1930s, based solely on morphological characters, no molecular data have confirmed this identification. We generated full‐length mitogenomes and partial chloroplast genomes of all representative holopelagic Sargassum species, S. fluitans III and S. natans I alongside the putatively rare S. natans VIII, to demonstrate small but consistent differences between S. natans I and VIII (7 bp differences out of the 34,727). Our comparative analyses also revealed that both S. natans I and S. natans VIII share a very close phylogenetic relationship with S. fluitans III (94‐ and 96‐bp differences of 34,727). We designed novel primers that amplified regions of the cox2 and cox3 marker genes with consistent polymorphic sites that enabled differentiation between the two S. natans forms (I and VIII) from each other and both from S. fluitans III in over 150 Sargassum samples including those from the 2014 golden tide event. Despite remarkable gene synteny and sequence conservation, the three Sargassum forms differ in morphology, ecology, and distribution patterns, warranting more extensive interrogation of holopelagic Sargassum genomes as a whole. 相似文献
137.
The phenology, flower morphology, pollination mechanism and reproductive biology of Epidendrum secundum were studied in a semi‐deciduous forest at the Serra do Japi (SJ), and in the Atlantic rain forest of Picinguaba, both natural reserves in the State of São Paulo, southeastern Brazil. E. secundum flowers all year round, with a flowering peak between September and January. This species is either a lithophytic or terrestrial herb in the SJ, whereas, in Picinguaba, it grows mainly in disturbed areas along roadsides. E. secundum is pollinated by several species of diurnal Lepidoptera at both study sites. In Picinguaba, where E. secundum is sympatric with E. fulgens and both share the same pollinators, pollen transference between these two species was recorded. E. secundum is self‐compatible but pollinator‐dependent. It is inter‐compatible with E. fulgens, producing fertile seeds. In contrast to the population of the SJ, in the Picinguaba region, floral morphology is quite variable among plants and some individuals present flowers with characteristics in‐between both sympatric species, suggesting that natural hybridization occasionally occurs. The anthropogenic perturbation is probably the cause of the occurrence of E. secundum in the Picinguaba region, enabling its contact with E. fulgens. 相似文献
138.
Eduardo N Taboada Joanne M MacKinnon Christian C Luebbert Victor PJ Gannon John HE Nash Kris Rahn 《BMC evolutionary biology》2008,8(1):229
Background
Multi-Locus Sequence Typing (MLST) has emerged as a leading molecular typing method owing to its high ability to discriminate among bacterial isolates, the relative ease with which data acquisition and analysis can be standardized, and the high portability of the resulting sequence data. While MLST has been successfully applied to the study of the population structure for a number of different bacterial species, it has also provided compelling evidence for high rates of recombination in some species. We have analyzed a set of Campylobacter jejuni strains using MLST and Comparative Genomic Hybridization (CGH) on a full-genome microarray in order to determine whether recombination and high levels of genomic mosaicism adversely affect the inference of strain relationships based on the analysis of a restricted number of genetic loci. 相似文献139.
PJS Amaral LFM Finotelo EHC De Oliveira A Pissinatti CY Nagamachi JC Pieczarka 《BMC evolutionary biology》2008,8(1):169
Background
Chromosomal painting, using whole chromosome probes from humans and Saguinus oedipus, was used to establish karyotypic divergence among species of the genus Cebus, including C. olivaceus, C. albifrons, C. apella robustus and C. apella paraguayanus. Cytogenetic studies suggested that the species of this genus have conservative karyotypes, with diploid numbers ranging from 2n = 52 to 2n = 54. 相似文献140.
Sónia Carneiro António L. Amaral Ana C. A. Veloso Teresa Dias António M. Peres Eugénio C. Ferreira Isabel Rocha 《Biotechnology progress》2009,25(3):882-891
The development of monitoring methods for assessing the physiological state of microorganisms during recombinant fermentation processes has been encouraged by the need to evaluate the influence of processing conditions in recombinant protein production. In this work, a technique based on microscopy and image analysis was developed that allows the simultaneous quantification of parameters associated with viability and fluorescent protein production in recombinant Escherichia coli fermentations. Images obtained from light microscopy with phase contrast are used to assess the total number of cells in a given sample and, from epifluorescence microscopy, both protein producing and injured cells are evaluated using two different fluorochromes: propidium iodide and enhanced yellow fluorescent protein. This technique revealed the existence of different cell populations in the recombinant E. coli fermentation broth that were evaluated along four batch fermentations, complementing information obtained with standard techniques to study the effects of the temperature and induction time in recombinant protein production processes. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献