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991.
Caterina DAngelo Angela Casillo Chiara Melchiorre Concetta Lauro Maria Michela Corsaro Andrea Carpentieri Maria Luisa Tutino Ermenegilda Parrilli 《Marine drugs》2022,20(12)
The development of new approaches to prevent microbial surface adhesion and biofilm formation is an emerging need following the growing understanding of the impact of biofilm-related infections on human health. Staphylococcus epidermidis, with its ability to form biofilm and colonize biomaterials, represents the most frequent causative agent involved in infections of medical devices. In the research of new anti-biofilm agents against S. epidermidis biofilm, Antarctic marine bacteria represent an untapped reservoir of biodiversity. In the present study, the attention was focused on Psychrobacter sp. TAE2020, an Antarctic marine bacterium that produces molecules able to impair the initial attachment of S. epidermidis strains to the polystyrene surface. The setup of suitable purification protocols allowed the identification by NMR spectroscopy and LC-MS/MS analysis of a protein–polysaccharide complex named CATASAN. This complex proved to be a very effective anti-biofilm agent. Indeed, it not only interferes with cell surface attachment, but also prevents biofilm formation and affects the mature biofilm matrix structure of S. epidermidis. Moreover, CATASAN is endowed with a good emulsification activity in a wide range of pH and temperature. Therefore, its use can be easily extended to different biotechnological applications. 相似文献
992.
José Roberto Pereira de Sousa Fernando da Silva Carvalho-Filho Maria Cristina Esposito 《Journal of insect science (Online)》2015,15(1)
This study aimed at surveying the local calliphorid and sarcophagid species in
Maranhão State (Brazil) to determine their distribution and abundance, as well
as the distribution of exotic Chrysomya species. In total, 18,128
calliphorid specimens were collected, distributed in 7 genera and 14 species. The
species Hemilucilia semidiaphana (Rondani, 1850) and
Paralucilia paraensis (Mello, 1969) were new state records.
Chrysomya albiceps (Wiedemann, 1819) and Cochliomyia
macellaria (F., 1775) were the most abundant species, and the exotic
species of Chrysomya together contributed more than 50% of
total blow fly abundance. The abundance distribution of the calliphorid community
conformed to a log series model, characterized by a steep curve that reflects an
assemblage with a high degree of dominance. For the Sarcophagidae, a total of 14,810
specimens were collected and distributed in 15 genera, 11 subgenera, and 52 species.
Tricharaea (Sarcophagula)
occidua (F., 1794) and Peckia
(Sarcodexia) lambens (Wiedemann, 1830) were the
most abundant species. The abundance distribution of the species followed a log
normal model, with a gentler slope, consistent with a more uniform community. The
cumulative species curve for the sarcophagids did not reach the asymptote.
Forty-three sarcophagid species were new state records and 22 were new records for
the Brazilian northeast, which emphasizes the need for a continued survey in this
region. 相似文献
993.
Maria Pilar Serrano‐Muela Estela Nadal‐Romero Noemí Lana‐Renault Jos Carlos Gonzlez‐Hidalgo Juan Ignacio Lpez‐Moreno Santiago Beguería Yasmina Sanjuan Jos María García‐Ruiz 《Land Degradation \u0026amp; Development》2015,26(3):249-262
An exceptional rainfall and hydrological event occurred on 19–21 October 2012 in the central western Pyrenees and was particularly significant in the Upper Aragón River basin and its tributaries, mainly the Irati River. Analysis of historical records showed that, considered separately, the event of 19 and 20 October ranked between the second and fifth highest most extreme daily precipitation events. For the two days combined (with a total between 200 and 260 mm), the precipitation event was the most extreme 2‐day event among all observation stations but one. The consequent flood destroyed part of an urban area, and a long stretch of a national road triggered landslides, enlarged the alluvial plain and caused generalised soil erosion in cultivated fields cropped with winter cereals. Badlands in the marls of the Inner Depression yielded high volumes of sediment. The floods in the tributaries were relatively moderate (return periods of 14–42 years), whereas in the Upper Aragón River, the flood corresponded to a return period of approximately 400–500 years and to 142 years at the end of the Yesa reservoir, although difficulties in estimating the discharge increased the uncertainty of these values. The Yesa and Itoiz reservoirs considerably reduced the intensity of the flood in the middle and lower Aragón River and confirmed the importance of the water level in the reservoirs when such rainfall events occur. The water storage in the Yesa reservoir increased from 16% to 53% as a consequence of the event. More integrated studies are necessary to decrease the risks associated with flood hazards. This is particularly the case in mountain areas, where the steep slopes and longitudinal gradients of the rivers shorten the concentration time of floods and increase the energy that erodes channels and riverbanks. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
994.
The concentrations of selected metals—Cr, Ni, Cu, Zn, Cd, and Pb—were determined in the samples of Hypogymnia physodes lichen and Pleurozium schreberi moss collected in Polish and Czech Euroregions Praded and Glacensis. More specifically, the samples were collected in Bory Stobrawskie, Bory Niemodlińskie, and Kotlina K?odzka (Poland) and in Jeseniki (Czech Republic). The concentration of metals in the samples was measured using the atomic absorption spectrometry (flame AAS technique and electrothermal atomization AAS technique). The results were used to calculate the comparison factor (CF) that quantifies the difference in concentration of a given bioavailable analyte × accumulated in lichens and mosses: CF?=?2 (c x,lichen ? c x,moss) (c x,lichen + c x,moss)?1. The values of CF greater than 0.62 indicate the most probable location of heavy metals deposited in the considered area. In this work, the method was used to show a significant contribution of urban emissions to the deposition of heavy metals in the area of Bory Stobrawskie and in the vicinity of K?odzko City. 相似文献
995.
Marcolino VA Zanin GM Durrant LR Benassi Mde T Matioli G 《Journal of agricultural and food chemistry》2011,59(7):3348-3357
This work aimed to compare methods for the formation of complexes of bixin and curcumin with β-cyclodextrin (β-CD) and to evaluate the stability of the complexes formed by these methods and their food applications. The stoichiometric relationship between curcumin and β-CD was 1:2 and that between bixin and β-CD was 1:1. Curcumin-β-CD and bixin-β-CD complexes formed by kneading, coprecipitation, and simple mixing were evaluated by differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), or nuclear magnetic resonance (NMR-H). For both curcumin and bixin, the best method of complexation was coprecipitation. Complexation of colorants with β-CD promoted an intensification of color and increased water solubility; however, stabilization in the presence of light occurred only for bixin. Application of curcumin-β-CD in cheese and yogurt and bixin-β-CD in the curd did not alter the initial characteristics of the products, which were sensorialy well accepted. Therefore, the complexation of these natural colorants with β-CD favors their use in low-fat foods, broadening the field of industrial application. 相似文献
996.
Properties of an aged phenanthrene-contaminated soil and its response to bioremediation processes 总被引:1,自引:0,他引:1
Purpose
Persistent organic compounds exhibit declining extractability and bioavailability to microorganisms and other soil organisms with increasing contact time or ageing. Among the possible mechanisms are the association of organic compounds with natural organic matter. Ageing can reduce the negative effects that an organic pollutant may have on the biological, biochemical properties and phytotoxicity of the contaminated soil. The aim of the present work was to evaluate, under laboratory conditions, the response of an agricultural soil contaminated with phenanthrene (Phe) and subjected to 2-year ageing and the effects and potential remediation capabilities of compost and an effective Phe-degrading bacterial culture. 相似文献997.
Fatima Maria de Souza Moreira Teotonio Soares de Carvalho José Oswaldo Siqueira 《Biology and Fertility of Soils》2010,46(8):771-779
The aim of this study was to evaluate the effects of lime, fertilizers, mycorrhizal fungi, and selected rhizobia strains on the growth of four woody legume species, Albizia lebbeck (L.) Benth., Enterolobium contortisiliquum (Vell.) Morong., Leucaena leucocephala (Lam.) de Wit, and Sesbania virgata (Cav.) Pers. in a low-fertility soil. The experiment was conducted under greenhouse condition in plastic pots (4 kg). Eight treatments and eight replicates per treatment were performed in a completely randomized design. The treatments were: (1) complete treatment (C) (NPK fertilization?+?micronutrients?+?liming?+?MR that is inoculation with mycorrhizal fungi and rhizobia); (2) C minus N (C???N that is as C without the addition of N); (3) C???N???M (as C???N without inoculation with arbuscular mycorrhizal fungi (AMF)); (4) C???N??R (as C???N without inoculation of rhizobia); (5) C???N???liming (as C???N without liming); (6) C???N???micro (as C???N without addition of micronutrients); (7) C???N???P (as C???N without addition of P); (8) control without fertilization, liming, and without inoculation with AMF and rhizobia. After 4 months of growth, we determined the yield of individual plants, nodulation, mycorrhizal colonization, and nutrient contents. Phosphorus was the most limiting nutrient for plant growth, followed by nitrogen. L. leucocephala and S. virgata had the most robust response to the addition of micronutrients and liming, showing an increase in nutrient content, plant height, and root and shoot dry matter. When compared to the single inoculation, the dual inoculation increased growth of all plants, except that of A. lebbeck, which did not respond to either rhizobia or mycorrhizal fungi inoculation. 相似文献
998.
Anna M. Stefanowicz Maria Nikliska Ryszard Laskowski 《European Journal of Soil Biology》2009,45(4):363-369
Pollution-induced community tolerance (PICT) allows finding a cause–effect relationship between pollution and adverse changes in a community. In our previous study we found that functional diversity of bacterial communities decreased significantly with increasing metal concentration, in both forest humus and meadow topsoil. Thus, the aim of the present study was to test whether tolerance of soil bacterial communities had increased as an effect of long-term metal pollution. Bacterial tolerance was tested with the use of the Biolog® ECO plates in soils originating from the most polluted and the least polluted sites from three forest and five meadow transects located near smelters in Avonmouth (England), Clydach (Wales), and Głogów and Olkusz (Poland). We found that tolerance of bacterial communities was significantly increased in polluted meadow soils when compared to control meadow soils. On the contrary, no increase in tolerance was detected in polluted forest humus. 相似文献
999.
Reduction of Nitrate and Ammonium Adsorption Using Microscale Iron Particles and Zeolitite 总被引:2,自引:0,他引:2
Silvia Comba Maria Martin Daniele Marchisio Rajandrea Sethi Elisabetta Barberis 《Water, air, and soil pollution》2012,223(3):1079-1089
Nitrate contamination of groundwater represents a threat to human health. Many researchers have studied zerovalent iron as
a mean to remediate nitrate contamination. However, the application of such method is limited by ammonium production. This
work investigates the use of microscale iron particles in association with zeolitite, a natural material containing zeolite,
to remove nitrate and ammonium from groundwater. The association of the two materials is shown to lower the nitrate concentration
in both deionized water and groundwater under the limit suggested by the European Union and to significantly reduce the ammonium
concentration. The method is potentially applicable in water filtration. 相似文献
1000.
Sánchez-Hernández L Nozal L Marina ML Crego AL 《Journal of agricultural and food chemistry》2012,60(4):896-903
A novel screening method using an automated flow injection electrospray ionization tandem mass spectrometry system is proposed for the simultaneous determination of five nonprotein amino acids (β-alanine, alloisoleucine, ornithine, citrulline, pyroglutamic acid) and three betaines (glycine betaine, trigonelline, proline betaine) after derivatization with butanolic HCl. MS/MS experiments were carried out in a triple-quadrupole instrument using multiple reaction monitoring mode in <2 min. The proposed method provided high fingerprinting power to identify the presence of five of the studied compounds in different types of vegetable oils (soybean, sunflower, corn, olive) with LODs at parts per billion levels. The method was validated, and different mixtures of extra virgin olive oil with seed oils were analyzed, achieving the typification for the detection of adulterations in extra virgin olive oils up to 2% w/w. The nonprotein amino acid ornithine was confirmed as a marker for adulteration in the olive oils analyzed. 相似文献