Identification of new antimicrobial peptides that contribute to the bactericidal activity of egg white against Salmonella enterica serovar Enteritidis at 45 °C

A recent work revealed that egg white (EW) at 45 °C exhibits powerful bactericidal activity against S. enterica serovar Enteritidis, which is surprisingly little affected by removal of the >10 kDa EW proteins. Here, we sought to identify the major EW factors responsible for this bactericidal activity by fractionating EW using ultrafiltration and nanofiltration and by characterizing the physicochemical and antimicrobial properties of the resulting fractions. In particular, 22 peptides were identified by nano-LC/MSMS and the bactericidal activities of representative peptides (with predicted antimicrobial activity) were further assessed. Two peptides (FVPPVQR and GDPSAWSWGAEAHS) were found to be bactericidal against S. enterica serovar Enteritidis at 45 °C when provided in an EW environment. Nevertheless, these peptides contribute only part of this bactericidal activity, suggesting other, yet to be determined, antimicrobial factors

A Temporal -omic Study of Propionibacterium freudenreichii CIRM-BIA1T Adaptation Strategies in Conditions Mimicking Cheese Ripening in the Cold

Propionibacterium freudenreichii is used as a ripening culture in Swiss cheese manufacture. It grows when cheeses are ripened in a warm room (about 24°C). Cheeses with an acceptable eye formation level are transferred to a cold room (about 4°C), inducing a marked slowdown of propionic fermentation, but P. freudenreichii remains active in the cold. To investigate the P. freudenreichii strategies of adaptation and survival in the cold, we performed the first global gene expression profile for this species. The time-course transcriptomic response of P. freudenreichii CIRM-BIA1T strain was analyzed at five times of incubation, during growth at 30°C then for 9 days at 4°C, under conditions preventing nutrient starvation. Gene expression was also confirmed by RT-qPCR for 28 genes. In addition, proteomic experiments were carried out and the main metabolites were quantified. Microarray analysis revealed that 565 genes (25% of the protein-coding sequences of P. freudenreichii genome) were differentially expressed during transition from 30°C to 4°C (P<0.05 and |fold change|>1). At 4°C, a general slowing down was observed for genes implicated in the cell machinery. On the contrary, P. freudenreichii CIRM-BIA1T strain over-expressed genes involved in lactate, alanine and serine conversion to pyruvate, in gluconeogenesis, and in glycogen synthesis. Interestingly, the expression of different genes involved in the formation of important cheese flavor compounds, remained unchanged at 4°C. This could explain the contribution of P. freudenreichii to cheese ripening even in the cold. In conclusion, P. freudenreichii remains metabolically active at 4°C and induces pathways to maintain its long-term survival

"Fête de la science" in Ferney-Voltaire, France

CERN participated to "Fête de la science" yearly event in the gardens of the Château de Voltaire on Saturday. Visitors of all ages had the opportunity to discover a few CERN activities in a fun and accessible way: antimatter show, a particle physics treasure hunt, pixel art and panoramic virtual tours of the accelerators

MODELING OF A GLASS WOOL PROCESS IN VIEW OF LIFE CYCLE ASSESSMENT (L.C.A.)

peer reviewedTaking into account the environmental aspects in the building sector has become unavoidable. In France, environmental and sanitary statements for building products (“Fiches de Déclarations Environnementales et Sanitaires” (FDE&S)) have been developed. The environmental part of the statement is based on Life Cycle Assessment. So, KnaufInsulation, glass wool producer for the French market, has started to evaluated the environmental impacts of it process in view of FDE&S realization. The process has been modeling in GaBi with industrial data. Adjustable parameters have been introduced to allow to study the environmental impacts of almost all the KnaufInsulation products. So the FDE&S can be easily done for the different products. This model is also used for eco-conception. The LCA results allow to show the life cycle leaks. More, in modifying the model, the impact of a change in the process on its environmental performances will be highlighted. So relevant improvement will be brought out. The model and the mains results as the eco-conception strategy will be presented. The interest of making a modeling based on the step and process of the life cycle of a product or a product range will be clearly understood

Fatty acid composition of total fat from Camembert cheeses with small and large native milk fat globules

Camembert cheeses were produced using either small (∼3 pm, SFG) or large (∼6 μm, LFG) native milk fat globules obtained by a patented microfiltration process. The total fatty acid composition in cheeses varied both according to ripening time and fat globule size. There were more medium-chain fatty acids in SFG cheeses, the content of which decreased with ripening time. Twenty days after manufacture, there were more saturated and unsaturated C18 acids in LFG than in SFG, on average. There was considerably more short-chain fatty acids in SFG than LFG at 40 days after manufacture, which can develop aromas. Sensory analysis revealed that the flavour intensity and richness of aromas were greater in SFG cheese. Results were explained by the greater surface area of native milk fat globule membrane for SFG vs LFG, at a given fat content, which can enhance lipolytic activity. The use of native milk fat globules with different sizes can thus lead to products with different sensory properties

CLA profile in native fat globules of different sizes selected from raw milk

The CLA content and isomer profile were characterized among two subclasses of the native milk fat globules. The latter corresponded to two fractions obtained by a microfiltration process using Spring mixed milk, leading to small fat globules (SFG; Click to view the MathML source) in the microfiltrates and large ones (LFG; Click to view the MathML source) in the retentates. Relatively, SFG always contained more CLA than the LFG originating from the same mixed milk, though discrepancies among different milk samples were observed. The main CLA isomer was the cis-9, trans-11, the content of which tended to increase when the native milk fat globule size decreased (from 82.2% to 87.3% of total CLA isomers). Consequently, the SFG contained less trans-12, trans-14; trans-11, trans-13; trans-11, cis-13 and trans-8, cis-10 isomers than the corresponding LFG. However, the relative variation of some isomers between small and large fat globule from the same milk varied depending on milk origin and the potential of fat globule fractionation for influencing the content and distribution of CLA seems to be limited

The fatty acid composition of small and large naturally occurring milk fat globules

DOI:10.1002/ejlt.200300812International audienc

The effect of co-infecting viruses on transgenic Plum pox virus resistant plums (Prunus domestica)

International audienc