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Antonia Nostro Roberto Scaffaro Giovanna Ginestra Manuela D’Arrigo Luigi Botta Andreana Marino Giuseppe Bisignano 《Applied microbiology and biotechnology》2010,87(2):729-737
The aim of this study was to evaluate the effect of poly-ethylene-co-vinyl acetate (EVA) films incorporating different concentrations
(0.1%, 0.5% and 1%) of nisin on the biofilm-forming ability of Listeria monocytogenes ATCC 7644, Staphylococcus aureus 815 and Staphylococcus epidermidis ATCC 35984. Nisin was incorporated into two grades of EVA (EVA14 and EVA28) in the melt during a common film-blowing operation.
The efficacy of EVA/nisin films was evaluated by biofilm biomass measurements and Live/Dead staining in combination with fluorescence
microscopy. In order to evaluate whether the nisin incorporation could modify the film surface properties, contact angle measurements
and scanning electron microscopy were performed. The results revealed the efficacy of EVA14/nisin films in reducing biofilm
formation on their surfaces with more evident effect for S. epidermidis than L. monocytogenes and S. aureus strains. In contrast, EVA28/nisin films showed unsatisfactory activity. Fluorescence microscopy confirmed poor biofilm formation
on EVA14/nisin films, also characterised by the presence of dead cells. The data presented in this study offer new potential
applications for developing strategies aimed to improve the effect of antimicrobial agents. 相似文献
94.
María?F.?MonteroEmail author Manuela?Aristizábal Guillermo?García Reina 《Journal of applied phycology》2011,23(6):1053-1057
Biodiesel from algae is considered an alternative for a third generation of biofuels. However, most microalgae are not lipogenic
during fast growth periods, but high-lipid content occurs at resting stages. Microalgae biomass production for biodiesel needs
continuous high volumetric and aerial yields and large amount of neutral lipid in the biomass. These requirements are similar
to demanding a marathon runner to be obese. We show that by using cell sorting capabilities of flow cytometers, in combination
with the lipid-soluble fluorescent dye Nile Red, we can isolate and select cells with a high and stable lipid content. In
our study, we were able to select the equivalent of a stable “fat marathon runner” through three sorting events obtained from
wild populations of Tetraselmis suecica. 相似文献
95.
Intron size in mammals: complexity comes to terms with economy 总被引:2,自引:0,他引:2
Pozzoli U Menozzi G Comi GP Cagliani R Bresolin N Sironi M 《Trends in genetics : TIG》2007,23(1):20-24
96.
Santos R Fernandes J Fernandes N Oliveira F Cadete M 《Applied and environmental microbiology》2007,73(15):5071-5073
Mycobacterium parascrofulaceum was found in Norris Geyser Basin, Yellowstone National Park, in a system composed of two acidic (pH 3.0) springs with temperatures between 56 degrees C at the source and 40 degrees C at the confluence of both springs. Growth and survival assays at 56 degrees C for 60 days were performed, confirming the origin of the strain. 相似文献
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98.
Hybridisation is an important evolutionary process. The investigation of hybridisation along elevational gradients, with their steep abiotic and biotic clines, provides insight into the adaptation and maintenance of species in adjacent habitats. The rare Senecio hercynicus and its spreading congener S. ovatus are vertically vicariant species that show hybridisation in their range overlaps. In the present study, we used AFLP fingerprinting of 689 individuals from 38 populations to analyse population structure and introgression patterns along four elevational transects (650–1350 m) in the Bavarian Forest National Park, Gemany. Subsequently, we searched for loci putatively under divergent selection that may maintain ‘pure’ species despite hybrid formation by identifying taxon-specific alleles. A maximum-likelihood based hybrid index shows that the overall genetic differentiation among all populations was very low with a vanishingly small number of pure parental individuals. Almost 75% of the investigated individuals were classified as backcrosses towards S. ovatus. The highest S. hercynicus ancestry was found in the uppermost populations of two transects. Further, we found seven taxon-specific alleles being under divergent selection that correlated with climatic variables and deviating from neutral introgression. According to our results, hybridisation of S. ovatus and S. hercynicus has reached an advanced state of genetic swamping and there seems to be no driving force that is strong enough to keep both species as different lineages. Rather, S. ovatus appears to benefit through putatively adaptive introgression. 相似文献
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Petrucci E Pasquini L Bernabei M Saulle E Biffoni M Accarpio F Sibio S Di Giorgio A Di Donato V Casorelli A Benedetti-Panici P Testa U 《PloS one》2012,7(4):e35073