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The present study investigated the phylogeny based on 16S rRNA gene sequences of psychrotrophic bacteria isolated from refrigerated raw cow milk collected in an arid area of Algeria. During cold storage of milk at 4°C, 29 bacterial morpho-physiotypes were selected among 177 isolates and were identified by partial 16S rRNA gene sequencing. The results of the phylogenetic analysis showed five clusters regrouping six genera namely Stenotrophomonas, Acinetobacter, Chryseobacterium, Lactobacillus, Aeromonas and Enterococcus. Enterococcus constituted the largest cluster composed of 9 taxa with E. faecalis being the predominant species and it was the most subclustered group. The comparative genomic analysis based on 16S rRNA gene sequence of E. faecalis isolates, with related strains from different geographies and climates was performed. The observations of the genetic variation showed that seven E. faecalis strains (MH569850, MH569851, MH569854, MH569856, MH569857, MH569859 and MH569860) registered similarities of sequences less than 97%, which lead to the hypothesis that the isolates could represent a novel species of the genus Enterococcus. The minor richness of the milk microbiota analyzed in this arid region may account for the intervention of environmental factors influencing the selection and the evolution of the microflora. [ABSTRACT FROM AUTHOR]

Polyurethanes (PURs) are polymers that can be generated by a step-growth polyaddition reaction of diisocyanates with polyols. The number of well-developed chemical procedures applicable to their manufacture, and the diversity of chemical structures in which polyurethanes can be built, account for the widespread use of these materials in the last few decades for both domestic and technical applications due to its excellent mechanical and thermal properties and their high resistance to the climatic changes. Nevertheless, its high resistance to degradation in aqueous media or bymicroorganism constitutes not only a great disadvantage for its use as material in medical applications (vascular grafts, artificial heart diaphragms, valves, catheters...) but also as one of the sources of the pollution of the environment. In this work, we report the degradation of a commercial poly (ester-urethane) by microorganisms isolated from cedar wood. This is the first study that demonstrates the degradation of polyurethane by isolated microorganisms from wood. Analyses were carried out by Infrared spectroscopy. [ABSTRACT FROM AUTHOR]