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51.
Laís Fernanda de Palma Lopes Vanessa Ochi Agostini Sanye Soroldoni Guimarães Erik Muxagata 《Chemistry and Ecology》2018,34(8):747-761
Cultures of the copepod Acartia tonsa are used both in aquaculture and ecotoxicology studies. However, the cultivation of these crustaceans at high densities results in the proliferation of microorganisms that can affect the organisms of interest, leading to illness or death. Antimicrobials inhibit microbial growth and may favour the cultivated species, aiding the development of ecological studies. This study investigated the potential of antimicrobials (antibiotic + antifungal) to inhibit bacteria and fungi when applied to marine zooplankton cultures, using the copepod A. tonsa as a bioindicator of acute toxicity. Treatment with 0.025?g?L?1 of penicillin G potassium + 0.08?g?L?1 of streptomycin sulphate + 0.04?g?L?1 of neomycin sulphate + 0.005?g?L?1 of nystatin resulted in 95% bacterial inhibition (after 12?h of exposure); however, after this time, the inhibitory effect was lost. The antimicrobial combination tested in this study prevented colonisation by fungi until 168?h after exposure, without causing acute toxicity to A. tonsa. Thus, it has potential for use in marine cultures of less sensitive organisms. 相似文献
52.
Paes FA Hissa DC Angelim AL Pinto NW Grangeiro TB Melo VM 《Water environment research》2012,84(3):274-281
This paper describes the phenotypic and genotypic diversity of a Gram-positive, aerobic bacterial population isolated from the chlorine tank of a wastewater treatment plant. A total of 12 sporeforming, rod-shaped isolates were identified using 16S rRNA gene sequencing and biochemical tests. Pairwise genetic comparisons revealed the identity among sequences obtained from isolates varied from 92.6 to 100%. Similarity searches on GenBank showed that five strains were closely related (99 to 100% identity) to Bacillus subtilis and two were almost identical (99%) to B. megaterium and B. licheniformis. Because the five remaining strains were either closely related (97 to 99% identity) or identical to B. cereus, B. thuringiensis, and B. anthracis, they were classified as belonging to the B. cereus group. Apart from one strain, all clades in the phylogenetic tree were identical to clusters formed in the dendrogram based on biochemical tests results. According to the biochemical profiles, all isolates were characterized as different strains. In addition to chlorine resistance, all isolates were found to be resistant to at least one of five antibiotics tested. These results identify the potential risk of spreading antibiotic resistance genes in the environment by chlorine-resistant strains of Bacillus. 相似文献
53.
Anthocyanins and tannins in ozone-fumigated guava trees 总被引:1,自引:0,他引:1
Psidium guajava “Paluma”, a tropical tree species, is known to be an efficient ozone indicator in tropical countries. When exposed to ozone, this species displays a characteristic leaf injury identified by inter-veinal red stippling on adaxial leaf surfaces. Following 30 days of three ozone treatments consisting of carbon filtered air (CF – AOT40 = 17 ppb h), ambient non-filtered air (NF – AOT40 = 542 ppb h) and ambient non-filtered air + 40 ppb ozone (NF + O3 – AOT40 = 7802 ppb h), the amounts of residual anthocyanins and tannins present in 10 P. guajava (“Paluma”) saplings were quantified. Higher amounts of anthocyanins were found in the NF + O3 treatment (1.6%) when compared to the CF (0.97%) and NF (1.30%) (p < 0.05), and of total tannins in the NF + O3 treatment (0.16%) compared to the CF (0.14%). Condensed tannins showed the same tendency as enhanced amounts. Regression analyses using amounts of tannins and anthocyanins, AOT40 and the leaf injury index (LII), showed a correlation between the leaf injury index and quantities of anthocyanins and total tannins. These results are in accordance with the association between the incidence of red-stippled leaves and ozone polluted environments. 相似文献
54.
Albatrosses and petrels (Procellariiformes) are migratory oceanic birds of considerable conservational interest. Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed in the subcutaneous fat, liver and muscle of 100 birds belonging to eight species of Procellariiformes collected during their migration period in southern Brazil, one of the most important feeding areas for these species. Although the profiles of PCBs and OCPs were similar among the individuals, with predominance of penta, hexa and heptachlorobiphenyls and p′p-DDE, organochlorine concentrations exhibited a high degree of intra-species variability. The influence of body condition during the migration period in the distribution of organochlorine contaminants was also evaluated, showing that it is a significant factor in the variation and redistribution of these compounds in the tissues of these birds. The intense use of lipid reserves associated to the contamination from organochlorine compounds could be a troubling factor for seabirds with extended breeding periods and that spend most of their lives at sea migrating long distances, such as most of Procellariiformes. Studies on contamination are necessary to improve the knowledge of the threats to these birds and their populations as well as to contribute with information about persistent organic pollutants in the South Atlantic marine environment. 相似文献
55.
Consuelo Fernanda Macedo de Souza José Ferreira Lima Jr Maria Soraya Pereira Franco Adriano Fabíola Galbiatti de Carvalho Franklin Delano Soares Forte Rosimere de Farias Oliveira Alexandre Pessoa Silva Fábio Correia Sampaio 《Environmental monitoring and assessment》2013,185(6):4735-4743
The aim of this study was to estimate the risk for caries and fluorosis in a desertification area, applying the calcium/fluoride concentration ratio of underground water and the quality of water in a selected geographical region. This study was performed in the municipality of São João do Rio do Peixe, located in the tropical semiarid lands of Brazil. A total of 111 groundwater samples were collected. Fluoride concentration varied from 0.11 to 9.33 mg/L. Thirty percent of all samples analyzed showed values above 1.5 mg/L, while 64 % were above the ideal limit of 0.7 mg/L. Mean calcium concentration was 47.6 mg/L, and 14.4 % of all samples presented values above the WHO acceptable limits. The proportional value of calcium/fluoride in water showed that only 12 % of the samples were suitable for dental caries prevention with minimal risk for dental fluorosis. Mapping of the fluoride distribution indicated that approximately 2,465 people could be affected by dental fluorosis and 1,057 people might be affected by skeletal fluorosis. It can be concluded that, in addition to fluoride, many water parameters were not suitable for the drinking water. Mapping out calcium/fluoride ratio may indicate areas of water suitability for caries control, whereas the fluoride concentration solely can indicate the areas with the risk for fluorosis. This approach can be relevant for health authorities for identifying communities where dental caries or dental fluorosis is prevalent. 相似文献
56.
Smichowski P Gómez DR Dawidowski LE Giné MF Bellato AC Reich SL 《Journal of environmental monitoring : JEM》2004,6(4):286-294
A study was undertaken, within the framework of a 3 years national project, to assess the content of 13 elements in airborne particulate matter collected in representative zones of the metropolitan area of Buenos Aires. The sampling strategy followed consisted in collecting simultaneously 67 samples of PM10 particulate matter in 9 sampling sites covering an area of about 30 km2 during one week. The collection was performed on ash-free fibre-glass filters using high volume samplers. A combination of aqua regia and perchloric acid was used for leaching metals from filters. Key elements, namely Al, Ca, Cu, Fe, Mn, Mo, Ni, Pb, S, Sb, Sn, Zn and Zr, were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS) at micro g g(-1) and ng g(-1) levels. Analyte concentration varied from 130 ng g(-1)(Mo) to over 30%(Ca). Multivariate statistical analysis was performed on the data set including the measured elemental compositions for the monitored period. The atmospheric concentration found for Pb confirms the decreasing levels of this element since the introduction of unleaded gasoline in 1995: 88 ng m(-3)(2001) < 220 ng m(-3)(1997) < 3900 ng m(-3)(1994). The average S concentration above 3 microg m(-3) is somehow unexpectedly high for Buenos Aires since the relatively low S content of liquid fuels and the massive usage of natural gas imply low emissions of this element from combustion activities. To the best of our knowledge, S concentrations are reported for the first time for this city. 相似文献
57.
M. Fernanda Alvarez Hernán H. Benítez J. Camilo Villegas Cortés Néstor A. Gabellone M. Cristina Claps 《Chemistry and Ecology》2016,32(8):742-755
Polyphenols – products of organic-matter decomposition entering water bodies from autochthonous and especially allochthonous sources – affect primary producers, bacterioplankton, and zooplankton to consequently modify food webs. Cladocerans are widely used in research experiments because they constitute the most frequent prey of high-trophic-level organisms in the majority of lakes, and certain species symbolise the ecologic prototype of the generalist filter feeder. In our study area’s shallow lakes, cladocerans, though generally of low abundance, do attain significantly high biomasses. We accordingly evaluated the mortality of the cladoceran Daphnia menucoensis Paggi, 1996 exposed to different tannin concentrations along with the bacterial abundance. In two experiments D. menucoensis females exposed to high tannin concentrations reproduced inefficiently, exhibited high mortality, and manifested altered behaviour, such as reduced reflexes and diminished mobility. Though tannins apparently affected algal abundances, the cladoceran herbivory strongly reduced those numbers. Positive effects on bacteria, however, were not recorded. High-allochthonous-organic-matter-containing water bodies support trophic webs because bacterioplankton provide an alternative energetic base for the zooplankton, as possibly occurs in shallow lakes of the Salado-River basin, characterised by cyclic hydrologic periods alternating between draught and flooding and intensive land use. In conclusion, tannins diminish D. menucoensis’s survival, locomotion, and the capacity to respond to stimuli. 相似文献
58.
Luciana Möller Fernanda Pedone Valdez Simon Allen Kerstin Bilgmann Shannon Corrigan Luciano B. Beheregaray 《Marine Biology》2011,158(1):113-126
Oceanographic processes play a significant role in shaping the genetic structure of marine populations, but it is less clear
whether they affect genetic differentiation of highly mobile vertebrates. We used microsatellite markers and mtDNA control
region sequences to investigate the spatial genetic structure of short-beaked common dolphins (Delphinus delphis) in southeastern Australia, a region characterised by complex oceanographic conditions associated with the East Australian
Current (EAC). A total of 115 biopsy samples of dolphins were collected from six localities spanning approximately 1,000 km
of the New South Wales (NSW) coastline. We found evidence for contrasting genetic diversity and fine-scale genetic structure,
characterised by three genetically differentiated populations with varying levels of admixture. Spatial genetic structure
was not explained by a model of isolation by distance, instead it coincides with main patterns of oceanographic variation
along the EAC. We propose that common dolphins along the EAC may be adapted to three water masses recently characterised in
this region. 相似文献
59.
Muñoz-Morales Martín Castañeda-Juárez Montse Souza Fernanda Lourdes Saez Cristina Cañizares Pablo Martínez-Miranda Verónica Linares-Hernández Ivonne Rodrigo Manuel Andrés 《Environmental science and pollution research international》2021,28(19):23657-23666
Environmental Science and Pollution Research - This work focuses on the development of electro-absorption and photoelectro-absorption technologies to treat gases produced by a synthetic waste... 相似文献
60.
Rodrigues Pinto Beatriz Linares Jose Joaquin de Vasconcelos Lanza Marcos Roberto de Lourdes Souza Fernanda 《Environmental science and pollution research international》2021,28(21):26762-26771
Environmental Science and Pollution Research - This paper reports the development of a novel photoelectrochemical (PEC) oxidation technique based on UV-C irradiation and boron-doped diamond (BDD)... 相似文献