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21.
Modern agriculture is dependent on phosphate rock (PR), which is a nonrenewable resource. Improvement of phosphorus (P) availability for crops in agricultural soils represents a key strategy to slow down the depletion of PR. The aim of this study was to identify potential P biofertilisers among saprotrophic fungal species. We tested 30 fungal strains belonging to 28 taxa (4 Zygomycota and 24 Ascomycota) and with different life strategies. The study showed that many saprotrophic fungi have the ability to mobilise P from insoluble forms according to a variety of mechanisms. Our results expand the pool of P solubilising fungal species, also suggesting a new solubilisation index and shedding light on parameters that could be basic in the selection of efficient soil P-biofertilisers fungi. Rhizopus stolonifer var. stolonifer, Aspergillus niger and Alternaria alternata were found to be the best performing strains in terms of amounts of TCP solubilisation. 相似文献
22.
Brassica juncea cv. 426308 was grown in soils containing 150 mg Cd(2+)kg(-1) soil. After 38 days, the soil was amended with two rates of citric acid or NTA (10 and 20 mmol kg(-1) soil). Control soil was not amended with chelates. Plants were harvested during growth, immediately before and seven days after chelate addition. Shoot composition of organic and phenolic acids and shoot Cd(2+) concentration were determined. Cadmium concentration remained constant during the growth and increased following NTA and citric acid amendments depending on chelate type and concentration. The highest increments in Cd(2+) were measured after the addition of NTA. Compared to the control, 10 and 20 NTA-treated plants showed two- and three-fold increases, respectively. At 150 mg Cd(2+)kg(-1) soil the amount of organic and phenolic acids in the leaves of B. juncea was always higher than that detected in the control. A direct correlation between organic acid concentration and cadmium content was detected both during growth and after chelate addition. On the contrary, the amount of phenols seemed to be correlated with the metal content only in non-amended and NTA-treated plants. The 10 and 20 citric acid additions caused 45% and 90% increases in shoot phenolic acids although cadmium content rose to a smaller extent. The inhibition of citrate synthase and the entrance of phosphoenolpyruvate in shikimate pathway leading to the formation of aromatic compounds might come into play. The increase in phenylalanine ammonialyase activity following citric acid amendments suggested this metabolic response. 相似文献
23.
Stranger M Potgieter-Vermaak S Sacco P Quaglio F Pagani D Cocheo C Godoi AF Van Grieken R 《Environmental monitoring and assessment》2009,149(1-4):411-417
A diffusive sampling method for the determination of gaseous acetic and formic acids, using a radial symmetry diffusive sampler, has been optimised for a 7-day exposure time in this study. Sampling rate determinations were performed on data obtained from a dynamic exposure chamber, simulating the indoor conditions of an empty, closed, room, at room temperature and minimal wind speed. Analysis has been performed by means of ion chromatography. The sampling rates for formic acid concentrations of 128 microg m(-3) and 1248 microg m(-3) were determined to be 91.2 +/- 3.9 ml min(-1) and 111.6 +/- 2.8 ml min(-1), respectively. The acetic acid sampling rate was independent of the concentration in the range 160 microg m(-3)-1564 microg m(-3), and amounted to 97.3 +/- 3.1 ml min(-1). Experimentally determined sampling rates showed deviations of 3% for acetic acid, and 3-21% for formic acid, in relation to theoretically derived values. The blank values were as low as 1.69 +/- 0.07 microg for formic acid and 1.21 +/- 0.14 microg for acetic acid, and detection limits lower than 0.5 microg m(-3) could be achieved, which is an improvement of 98-99% compared to previously validated diffusive sampling methods. This study describes the first step of an extended validation program in which the applicability of these types of samplers for the measurement of organic acids will be validated and optimised for the environmental conditions typical for museum showcases. 相似文献
24.
Meritxell Aulinas Maite Garcia-Valles Domingo Gimeno Jose Luis Fernandez-Turiel Flavia Ruggieri Montserrat Pugès 《Environmental science and pollution research international》2009,16(4):443-452
Background, aim, and scope The first step in the restoration of a medieval stained glass window is the evaluation of its degree of degradation. This
implies the study of the chemical composition of the stained glass as well as the new mineral phases developed on its surface
(patinas). Patinas are clearly related to glass composition, time, environmental conditions, microenvironments developed in
local zones, bioactivity, physical and chemical factors, etc. This study was carried out on patinas developed in selected
Na-rich stained glass of the Santa Maria de Pedralbes Monastery (Barcelona, Spain). The location of this monument in the city
(about 5 km from the shoreline and close to the Collserola hill flank) helped to determine the environmental conditions in
which patinas developed. The aim of our study was to characterize the patinas formed on the surface of the selected glass
of this monastery in order to understand the role of the chemical composition of the original glass (Na-rich) as well as the
environmental conditions in which they developed.
Materials and methods Powdered samples of two different color-type patinas (ochre-orange and brownish) were collected in the external and internal
parts of the stained glass windows of the Prebystery and Chapter House of the Pedralbes Monastery by using a precision (odontological)
drill. These patinas were subsequently analyzed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR).
Results XRD analyses evidenced the presence of sulfates (gypsum and thenardite), calcite, Ca-oxalates (whewellite and weddellite),
and quartz forming part of the patinas. Although these mineral phases can be found in both color-type patinas, whewellite
and thenardite are more common in the ochre-orange patinas. The results obtained were validated by the FTIR measurements.
It has been observed, when thenardite is present, that gypsum occurs as traces. Thenardite is in most of the cases associated
with whewellite and mainly occurs in the internal parts of the glass. In contrast, weddellite is limited to the absence of
thenardite and whewellite and to the external parts of the stained glass. Quartz is present in all the patinas independent
of their location and color. Calcite also occurs in many samples. It appears in both color-type patinas and, in some cases,
is associated to the presence of weddellite but not to whewellite and/or thenardite.
Discussion Glass composition together with environmental conditions and location of the patinas (internal or external parts of the stained
glass window), as well as the provenance of the glass within the monastery, are the main factors that define the development
of the new mineral phases. Moreover, the action of microorganisms, when present, can also strongly influence the development
of some mineral phases. For example, the formation of calcite in the external parts of the stained glass (associated with
the presence of oxalates) is related to the action of microorganisms. When calcite is formed in the internal parts of the
glass and it is not associated with the presence of Ca-oxalates, an inorganic origin can be invoked. The presence of weddellite
requires a very humid microenvironment with very little exposure to sunlight. In fact, this mineral phase has only been observed
in the external parts of some glass located in the humid and shady side of the monastery. Whewellite (which only appears in
the internal parts) needs a low degree of relative humidity. It has been observed that sulfur precipitating in basically one
mineral phase (thenardite or gypsum) depends on the microenvironmental conditions of the moment and the glass composition.
When thenardite occurs, it can be maintained that the original glass is of Na composition. The occurrence of quartz in all
samples is interpreted as being due to the deposition of atmospheric particulate matter. The color of the patinas can be originated
by different processes (presence of carotenes, organic pigmentation, atmospheric contamination, etc.).
Conclusions In the case of moderately weathered stained glass windows, the combination of XRD and FTIR techniques is very useful to obtain
a fast preliminary evaluation of the degree of weathering of a stained glass window. The presence of specific mineral phases
in the patina (e.g., thenardite) confirms the Na composition of the original stained glass. This is important since Na-rich
glass underwent a lesser degree of weathering than K- or K-Ca-rich glass. However, their absence cannot preclude other possibilities.
It has been extensively evidenced through time that environmental conditions play an important role on the formation of the
different mineral phases which form part of the patinas.
Recommendations and perspectives The first step in the restoration of a stained glass window is the evaluation of the degree of deterioration of the glass.
This evaluation includes a chemical analysis of the glass as well as a characterization of the patinas developed on their
surfaces. The obtained results will be essential in order to define the best restoration practices to be followed. 相似文献
25.
Cerumen, or propolis, is a mixture of plant resins enriched with bee secretions. In Australia, stingless bees are important
pollinators that use cerumen for nest construction and possibly for colony’s health. While extensive research attests to the
therapeutic properties of honeybee (Apis mellifera) propolis, the biological and medicinal properties of Australian stingless bee cerumen are largely unknown. In this study,
the chemical and biological properties of polar extracts of cerumen from Tetragonula carbonaria in South East Queensland, Australia were investigated using gas chromatography-mass spectrometry (GC-MS) analyses and in
vitro 5-lipoxygenase (5-LOX) cell-free assays. Extracts were tested against comparative (commercial tincture of A. mellifera propolis) and positive controls (Trolox and gallic acid). Distinct GC-MS fingerprints of a mixed diterpenic profile typical
of native bee cerumen were obtained with pimaric acid (6.31 ± 0.97%, w/w), isopimaric acid (12.23 ± 3.03%, w/w), and gallic
acid (5.79 ± 0.81%, w/w) tentatively identified as useful chemical markers. Characteristic flavonoids and prenylated phenolics
found in honeybee propolis were absent. Cerumen extracts from T. carbonaria inhibited activity of 5-LOX, an enzyme known to catalyse production of proinflammatory mediators (IC50 19.97 ± 2.67 μg/ml, mean ± SEM, n = 4). Extracts had similar potency to Trolox (IC50 12.78 ± 1.82 μg/ml), but were less potent than honeybee propolis (IC50 5.90 ± 0.62 μg/ml) or gallic acid (IC50 5.62 ± 0.35 μg/ml, P < 0.001). These findings warrant further investigation of the ecological and medicinal properties of this stingless bee cerumen,
which may herald a commercial potential for the Australian beekeeping industry. 相似文献
26.
Isolation and characterization of a Pseudomonas aeruginosa from a virgin Brazilian Amazon region with potential to degrade atrazine 总被引:1,自引:0,他引:1
Ana Flavia Tonelli Fernandes Michelle Barbosa Partata da Silva Vinicius Vicente Martins Carlos Eduardo Saraiva Miranda Eliana Guedes Stehling 《Environmental science and pollution research international》2014,21(24):13974-13978
The use of pesticides to increase agricultural production can result in the contamination of the environment, causing changes in the genetic structure of organisms and in the loss of biodiversity. This practice is also inducing changes in the rainforest ecosystem. In this work, a Pseudomonas aeruginosa isolated from a preservation soil area of the Brazilian Amazon Forest, without usage of any pesticide, was evaluated for its potential to degrade atrazine. This isolate presented all responsible genes (atzA, atzB, atzC, atzD, atzE, and atzF) for atrazine mineralization and demonstrated capacity to use atrazine as a nitrogen source, having achieved a reduction of 44 % of the initial concentration of atrazine after 24 h. These results confirm gene dispersion and/or a possible contamination of the area with the herbicide, which reinforces global concern of the increase and intensive use of pesticides worldwide. 相似文献
27.
Anna Rosa Sprocati Chiara Alisi Flavia Tasso Alessia Fiore Paola Marconi Francesca Langella Götz Haferburg Andrei Nicoara Aurora Neagoe Erika Kothe 《Environmental science and pollution research international》2014,21(11):6824-6835
The planetary importance of microbial function requires urgently that our knowledge and our exploitation ability is extended, therefore every occasion of bioprospecting is welcome. In this work, bioprospecting is presented from the perspective of the UMBRELLA project, whose main goal was to develop an integral approach for remediation of soil influenced by mining activity, by using microorganisms in association with plants. Accordingly, this work relies on the cultivable fraction of microbial biodiversity, native to six mining sites across Europe, different for geographical, climatic and geochemical characteristics but similar for suffering from chronic stress. The comparative analysis of the soil functional diversity, resulting from the metabolic profiling at community level (BIOLOG ECOPlates) and confirmed by the multivariate analysis, separates the six soils in two clusters, identifying soils characterised by low functional diversity and low metabolic activity. The microbial biodiversity falls into four major bacterial phyla: Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes, including a total of 47 genera and 99 species. In each soil, despite harsh conditions, metabolic capacity of nitrogen fixation and plant growth promotion were quite widespread, and most of the strains showed multiple resistances to heavy metals. At species-level, Shannon’s index (alpha diversity) and Sørensen's Similarity (beta diversity) indicates the sites are indeed diverse. Multivariate analysis of soil chemical factors and biodiversity identifies for each soil well-discriminating chemical factors and species, supporting the assumption that cultured biodiversity from the six mining sites presents, at phylum level, a convergence correlated to soil factors rather than to geographical factors while, at species level, reflects a remarkable local characterisation. 相似文献
28.
Santos FF Martin-Neto L Airoldi FP Rezende MO 《Journal of environmental science and health. Part. B》2005,40(5):721-730
This paper reports the effect of ultraviolet radiation on the degradation of pesticide ethyl parathion in the presence of humic acids. Ethyl parathion was completely degraded in 300 min using an artificial lamp of 7.41 x 10(-10) einstein/s. Humic acid from peat did not influence the photochemical rate (k = 8.92 x 10(-3) min). However, in the presence of aquatic humic acid, the photochemical rate was higher (11.5 x 10(-3) min). The analytical determinations show the presence of p-nitrophenol and aminophenol in the reaction medium during the photochemical experiments. The kinetic of degradation in all experiments obeyed a first-order reaction pattern. 相似文献
29.
Anna Jolanta Buczynska Agnieszka Krata Marianne Stranger Ana Flavia Locateli Godoi Velichka Kontozova-Deutsch László Bencs Inge Naveau Edward Roekens René Van Grieken 《Atmospheric environment (Oxford, England : 1994)》2009,43(2):311-318
The major threat to clean air in developed and industrializing countries is now posed by traffic emissions. The effects of traffic road modifications on the air quality are, however, rarely reported in the literature. The aim of this study was to determine the influence of the modernization and renovation of a traffic artery in the region of Mortsel (Antwerp, Belgium) on the concentration of volatile organic compounds such as: benzene, toluene, ethylbenzene and m-, p-, o-xylenes (BTEX). The original goal of the reconstruction works was to reduce the traffic lanes of one of the busiest streets in Antwerp, in order to discourage the road traffic and in consequence also to improve the air quality in this region. The average concentrations of BTEX before these works in 2003 were: 1.6, 7.0, 0.9, 2.3, and 0.9 μg/m3, for benzene, toluene, ethylbenzene, m + p xylenes, and o-xylene, respectively. However, after the completion of the works, in 2005, they were slightly higher: 2.5, 9.5, 1.6, 3.4, and 1.3 μg/m3, respectively. The scatter plots of benzene against toluene, ethylbenzene and xylenes in 2003 and 2005 showed very good correlations. This fact indicated that all of the measured compounds originated from the same source, namely the road traffic. Moreover, the data obtained from an air-monitoring station at less than 6 km distance from the sampling site (operated by the Flemish Environment Agency, and located in Borgerhout, Antwerp), confirmed the lack of influence of background concentrations of BTEX. The obtained results led to the conclusion that the reduction of the number of traffic lanes had apparently increased the traffic jams and also increased the emission from cars. Therefore, these modernization works had even a negative impact on the local concentration of traffic-related pollutants as BTEX. 相似文献
30.
Francisco Luiza Flavia Veiga do Amaral Crispim Bruno Spósito Juliana Caroline Vivian Solórzano Julio César Jut Maran Nayara Halimy Kummrow Fábio do Nascimento Valter Aragão Montagner Cassiana Carolina De Oliveira Kelly Mari Pires Barufatti Alexeia 《Environmental science and pollution research international》2019,26(24):24581-24594
Environmental Science and Pollution Research - Groundwaters are normally consumed without previous treatment and therefore the monitoring of contaminants in order to guarantee its safety is... 相似文献