Time filter

Source Type

Abiusi F.,University of Florence | Sampietro G.,University of Florence | Marturano G.,University of Florence | Biondi N.,University of Florence | And 4 more authors.
Biotechnology and Bioengineering | Year: 2014

The effect of light quality on cell size and cell cycle, growth rate, productivity, photosynthetic efficiency and biomass composition of the marine prasinophyte Tetraselmis suecica F&M-M33 grown in 2-L flat panel photobioreactors illuminated with light emitting diodes (LEDs) of different colors was investigated. Biomass productivity and photosynthetic efficiency were comparable between white and red light, while under blue and green light productivity decreased to less than half and photosynthetic efficiency to about one third. Differences in cell size and number correlated with the cell cycle phase. Under red light cells were smaller and more motile. Chlorophyll content was strongly reduced with red and enhanced with blue light, while carotenoids and gross biomass composition were not affected by light quality. The eicosapentaenoic acid content increased under red light. Red light can substitute white light without affecting productivity of T. suecica F&M-M33, leading to smaller and more motile cells and increased eicosapentaenoic acid content. Red LEDs can thus be profitably used for the production of this microalga for aquaculture. Biotechnol. Biotechnol. Bioeng. 2014;111: 956-964. © 2013 Wiley Periodicals, Inc. Source

Romoli R.,Centro Of Servizi Of Spettrometria Of Massa Cism | Papaleo M.C.,University of Florence | De Pascale D.,National Research Council Italy | Tutino M.L.,University of Naples Federico II | And 5 more authors.
Journal of Mass Spectrometry | Year: 2011

Bacteria belonging to the Burkholderia cepacia complex (Bcc) are significant pathogens in Cystic Fibrosis (CF) patients and are resistant to a plethora of antibiotics. In this context, microorganisms from Antarctica are interesting because they produce antimicrobial compounds inhibiting the growth of other bacteria. This is particularly true for bacteria isolated from Antarctic sponges. The aim of this work was to characterize a set of Antarctic bacteria for their ability to produce new natural drugs that could be exploited in the control of infections in CF patients by Bcc bacteria. Hence, 11 bacterial strains allocated to different genera (e.g., Pseudoalteromonas, Arthrobacter and Psychrobacter) were tested for their ability to inhibit the growth of 21 Bcc strains and some other human pathogens. All these bacteria completely inhibited the growth of most, if not all, Bcc strains, suggesting a highly specific activity toward Bcc strains. Experimental evidences showed that the antimicrobial compounds are small volatile organic compounds, and are constitutively produced via an unknown pathway. The microbial volatile profile was obtained by SPME-GC-MS within the m/z interval of 40-450. Solid phase micro extraction technique affords the possibility to extract the volatile compounds in head space with a minimal sample perturbation. Principal component analysis and successive cluster discriminant analysis was applied to evaluate the relationships among the volatile organic compounds with the aim of classifying the microorganisms by their volatile profile. These data highlight the potentiality of Antarctic bacteria as novel sources of antibacterial substances to face Bcc infections in CF patients. Copyright © 2011 John Wiley & Sons, Ltd. Source

Mulinacci N.,CeRA Centro Interdipartimentale per la Ricerca e Valorizzazione degli Alimenti | Ieri F.,Phytolab | Ieri F.,CeRA Centro Interdipartimentale per la Ricerca e Valorizzazione degli Alimenti | Ignesti G.,CeRA Centro Interdipartimentale per la Ricerca e Valorizzazione degli Alimenti | And 8 more authors.
Food Research International | Year: 2013

The effects of a long storage period on some Tuscan EVOOs filtered and frozen at - 23. °C in comparison with the same specimens maintained at room temperature in the dark, were evaluated by monitoring the evolution of their phenolic composition and aromatic profile.The oils were analyzed immediately after opening and after 10. days up to 18. months after oil bottling. A non parametric statistical analysis and principal components analysis (PCA) coupled to linear discriminant analysis (LDA) was applied for assessing the differences among the trials.Increments in tyrosol, hydroxytyrosol and % of hydrolysis were observed for EVOOs stored at room temperatures starting from 3-months storage, and increased thereafter. The frozen EVOOs were statistically undistinguishable over time, differently from the correspondent ones at room temperature. All the frozen EVOOs showed negligible differences in aromatic profile until 12. month of storage. Some compounds potentially related to off-odor sensations were significantly increased in the unfrozen specimens only at 18. months. © 2013 Elsevier Ltd. Source

Discover hidden collaborations