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Your search keyword '"BESTETTI, GIUSEPPINA"' showing total 9 results
Start Over Author "BESTETTI, GIUSEPPINA" Publisher springer-verlag
9 results on '"BESTETTI, GIUSEPPINA"'

7. Seasonal variability of bacteria in fine and coarse urban air particulate matter

Author

Franzetti, A, Gandolfi, I, Gaspari, E, Ambrosini, R, Bestetti, G, FRANZETTI, ANDREA, GANDOLFI, ISABELLA, AMBROSINI, ROBERTO, BESTETTI, GIUSEPPINA, Franzetti, A, Gandolfi, I, Gaspari, E, Ambrosini, R, Bestetti, G, FRANZETTI, ANDREA, GANDOLFI, ISABELLA, AMBROSINI, ROBERTO, and BESTETTI, GIUSEPPINA

Abstract

The current knowledge about the microbial communities associated with airborne particulate matter, particularly in urban areas, is limited. This study aims to fill this gap by describing the microbial community associated with coarse (PM10) and fine (PM2.5) particulate matter using pyrosequencing. Particulate matter was sampled on Teflon filters over 3 months in summer and 3 months in winter in Milan (Italy), and the hypervariable V3 region of the gene 16S rRNA amplified from the DNA extracted from the filters. The results showed large seasonal variations in the microbial communities, with plant-associated bacteria dominating in summer and spore-forming bacteria in winter. Bacterial communities from PM10 and PM2.5 were also found to differ from each other by season. In all samples, a high species richness, comparable with that of soils, but a low evenness was found. The results suggest that not only can the sources of the particulate influence the presence of specific bacterial groups but also that environmental factors and stresses can shape the bacterial community. © 2010 Springer-Verlag.

Published
2011

8. Microbial biosurfactants production, applications and future potential

Author

Banat, I, Franzetti, A, Gandolfi, I, Bestetti, G, Martinotti, M, Fracchia, L, Smyth, T, Marchant, R, Banat, IM, FRANZETTI, ANDREA, GANDOLFI, ISABELLA, BESTETTI, GIUSEPPINA, Martinotti, MG, Smyth, TJP, Marchant, R., Banat, I, Franzetti, A, Gandolfi, I, Bestetti, G, Martinotti, M, Fracchia, L, Smyth, T, Marchant, R, Banat, IM, FRANZETTI, ANDREA, GANDOLFI, ISABELLA, BESTETTI, GIUSEPPINA, Martinotti, MG, Smyth, TJP, and Marchant, R.

Abstract

Microorganisms synthesise a wide range of surface-active compounds (SAC), generally called biosurfactants. These compounds are mainly classified according to their molecular weight, physico-chemical properties and mode of action. The low-molecular-weight SACs or biosur-factants reduce the surface tension at the air/water interfaces and the interfacial tension at oil/water interfaces, whereas the high-molecular-weight SACs, also called bioemulsifiers, are more effective in stabilising oil-in-water emulsions. Biosur-factants are attracting much interest due to their potential advantages over their synthetic counterparts in many fields spanning environmental, food, biomedical, and other industrial applications. Their large-scale application and production, however, are currently limited by the high cost of production and by limited understanding of their interactions with cells and with the abiotic environment. In this paper, we review the current knowledge and the latest advances in biosurfactant applications and the biotechnological strategies being developed for improving production processes and future potential. © Springer-Verlag 2010.

Published
2010

9. Diversity and Assembling Processes of Bacterial Communities in Cryoconite Holes of a Karakoram Glacier.

Author

Ambrosini R, Musitelli F, Navarra F, Tagliaferri I, Gandolfi I, Bestetti G, Mayer C, Minora U, Azzoni RS, Diolaiuti G, Smiraglia C, and Franzetti A

Subjects
Bacteria genetics, Biota, DNA, Bacterial, Ecosystem, Genes, Bacterial, High-Throughput Screening Assays methods, Hydrogen-Ion Concentration, Lakes microbiology, Microbial Consortia, Pakistan, RNA, Ribosomal, 16S genetics, Bacteria classification, Bacteria isolation & purification, Biodiversity, Ice Cover microbiology
Abstract

Cryoconite holes are small ponds that form on the surface of glaciers that contain a dark debris, the cryoconite, at the bottom and host active ecological communities. Differences in the structure of bacterial communities have been documented among Arctic and mountain glaciers, and among glaciers in different areas of the world. In this study, we investigated the structure of bacterial communities of cryoconite holes of Baltoro Glacier, a large (62 km in length and 524 km 2 of surface) glacier of the Karakoram, by high-throughput sequencing of the V5-V6 hypervariable regions of the 16S rRNA gene. We found that Betaproteobacteria dominated bacterial communities, with large abundance of genera Polaromonas, probably thanks to its highly versatile metabolism, and Limnohabitans, which may have been favoured by the presence of supraglacial lakes in the area where cryoconite holes were sampled. Variation in bacterial communities among different sampling areas of the glacier could be explained by divergent selective processes driven by variation in environmental conditions, particularly pH, which was the only environmental variable that significantly affected the structure of bacterial communities. This variability may be due to both temporal and spatial patterns of variation in environmental conditions.

Published
2017
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