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Assignment of co-abundance groups of the most abundant OTUs (CAO) and their evolution across the individual microbiota steady states. For each crewmember, CAO were determined by heat plot showing Kendall correlations between the most abundant OTUs clustered by Spearman correlation and Ward linkage, as described in Claesson et al. [13]. All CAO displayed significantly different inter-relationships from each other (P 0.1% of mean relative abundance among the individual steady state profiles. (PDF 2955 kb)

The present work was mainly focused to study the response of representative non pathogenic microorganisms to the environment inside the space vehicle at different mission stages (10, 56, and 226 days) within the frame of the Italian ENEIDE mission, from Feb to Oct 2005. Microorganisms were chosen according to their phylogenetic position and cell structures; they were representatives of the three taxonomic domains and belonged to different ecosystems (food, soil, intestinal tract, plants, deep-sea). They were the followings: Thermococcus guaymasensis (Domain Archaea); Saccharomyces cerevisiae (Domain Eucarya); Escherichia coli, Bacillus subtilis, Lactobacillus acidophilus, Enterococcus faecium, Pseudomonas fluorescens, and Rhizobium tropici (Domain Bacteria). As main environmental parameters we were interested in: a) space radiations; b) microgravity; c) temperature. The response of microorganisms was investigated in terms of survival rates, cell structure modifications, and genomic damages. The survival of cells was affected by both radiation doses and intrinsec cell features. As expected, only samples kept on the ISS for 226 days showed significant levels of mortality. Asfar as regard the effect on cell structures, these samples showed also remarkable morphological changes, particularly for Escherichia coli, Enterococcus faecium, and Saccharomyces cerevisiae. The data collected allowed to get new insights into the biological traits of microorganisms exposed to space environment during the flight on a spacecraft. Moreover, the result obtained may be important for the improvement of human conditions aboard space vehicles (nutraceuticals for astronauts and disinfections of ISS modules) and also for the potential development of closed systems devoted to vegetable productions and organic recycling.

Genome sequencing of two exoelectrogenic bacteria isolated from soil and assessment of their metabolic profile by means of Phenotype Microarrays. 4.International Congress Eurosoil 2012 - Soil Science for the Benefit of Mankind and Environment

Potential probiotic strains from different origins have been tested for some specific physiological properties in order to evaluate their application potentialities. The phenotypic characterisations of examined lactic acid bacteria have done using the API tests and BIOLOG system. All of tested strains survive lyophilization process in skim milk at high population level. Lyophilised strains remained viable at all examined temperatures during 75 days of storage. Recovery of viable cells during storage in the phosphate buffer with glycerol was about 100 % at – 20 oC for all strains. Cells of L. acidophilus M92 rapidly died during storage at 4 and 15 oC, while cells of L. plantarum L4 and E. faecium L3 survive at the number of ca. 104 cells/ml. The potential probiotic strains have shown antagonistic activity against all tested gram-positive and gram-negative spoilage and pathogenic bacteria using 3 different methods (agar-spot test, agar-well diffusion method and in vitro competition test). The inhibition obtained by neutralised 5-fold concentrated supernatant of L. plantarum L4 may be result of bacteriocin activity of this strain.

I microrganismi probiotici vengono utilizzati fin dall’ antichità per prevenire o ridurre infezioni comuni sia nel settore umano che nel settore zootecnico. Lo scopo della ricerca è stato quello di isolare da ambienti diversi quali latte, vegetali e pesci batteri potenzialmente probiotici al fine di una loro applicazione nei settori agro-alimentari. Più di 400 ceppi sono stati isolati da diversi campioni e rispettivamente 155 da latte di vacca, 135 da insilati e 114 dal tratto intestinale della spigola, per mezzo di differenti terreni colturali (Peptone-Tryptone-Glucosio, Nutrient Broth, Marine Broth-2% NaCl ; selettivo per batteri generici ; M17, elettivo per streptococchi lattici ; Rosa Bengala, selettivo per lieviti e MRS, elettivo per lattobacilli). E’ stato studiato l'effetto sulla crescita del pH, della temperatura e della salinità e da un totale di 404 ceppi batterici ne sono stati individuati 21 con potenzialità probiotiche. Per una eventuale applicazione nel settore umano 3 ceppi sono stati saggiati rispetto la tolleranza alla bile. Tutti i batteri sono stati inoltre saggiati con prove di competizione in vitro (Spot Test, Pozzetti) nei confronti dei potenziali patogeni Vibrio anguillarum, Bacillus cereus, Salmonella typhimurium, Acinetobacter calcoaceticus, Listeria monocytogenes, Yersinia enterocolitica e Escherichia coli.

Potential probiotic strains from different origins have been tested for some specific physiological properties in order to evaluate their application potentialities. The phenotypic characterisation of examined lactic acid bacteria have done using the API tests and BIOLOG system. All of tested strains survive lyophilization process in skim milk at high population level. Lyophilised strains remained viable at all examined temperatures during 75 days of storage. Recovery of viable cells during storage in the phosphate buffer with glycerol was about 100 % at – 20 oC for all strains. Cells of L. acidophilus M92 rapidly died during storage at 4 and 15 oC, while cells of L. plantarum L4 and E. faecium L3 survive at the number of ca. 104 cells/ml. The potential probiotic strains have shown antagonistic activity against all tested gram-positive and gram-negative spoilage and pathogenic bacteria using 3 different methods (agar-spot test, agar-well diffusion method and in vitro competition test). The inhibition obtained by neutralised 5-fold concentrated supernatant of L. plantarum L4 may be result of bacteriocin activity of this strain.