How Listeria monocytogenes Shapes Its Proteome in Response to Natural Antimicrobial Compounds

The goal of this study was to investigate the adaptation of L. monocytogenes Scott A cells to treatments with sublethal doses of antimicrobials (ethanol, citral, carvacrol, E-2-hexenal and thyme essential oil). The survival of L. monocytogenes cells was not affected by the antimicrobials at the concentrations assayed, with the exception of ethanol (1% v/v) and thyme essential oil (100 mg/L), which decreased cell viability from 8.53 \ub1 0.36 to 7.20 \ub1 0.22 log CFU/mL (P = 0.04). We subsequently evaluated how L. monocytogenes regulates and shapes its proteome in response to antimicrobial compounds. Compared to the control cells grown under optimal conditions, L. monocytogenes treated for 1 h with the antimicrobial compounds showed increased or decreased ( 65 or 642-fold, respectively, P < 0.05) levels of protein synthesis for 223 protein spots. As shown multivariate clustering analysis, the proteome profiles differed between treatments. Adaptation and shaping of proteomes mainly concerned cell cycle control, cell division, chromosome, motility and regulatory related proteins, carbohydrate, pyruvate, nucleotide and nitrogen metabolism, cofactors and vitamins and stress response with contrasting responses for different stresses. Ethanol, citral (85 mg/l) or (E)-2-hexenal (150 mg/L) adapted cells increased survival during acid stress imposed under model (BHI) and food-like systems

Evaluation of Common Bean Varieties for Yield and Yield Component in Segen Area Peoples Zone SNNPRS, Ethiopia

Studies on the evaluation of variety performance provide opportunities to increase productivity of common bean. Therefore, the current study evaluates the performance of varieties on yield and yield components of common bean during the main cropping season of 2015 and 2016 at four locations in Segen Zone,Konso woreda (Southwestern Ethiopia) with the objectives of  selecting high yielding common bean varieties those are adapted to the study area. Fifteen released common bean varieties and one local cultivar were planted in randomized complete block design with three replications. The analysis revealed that significant variation for all traits except maturity date. Highest yield obtained from Nasir(2136 kgha-1) and Hawassa dume (1948 kgha-1) followed by Sari (1751 kgha-1) were as at Addis Gebere, high grain yield was obtained from Sari (2227 kgha-1), Hawassa dume (2111 kgha-1) and Dimtu (2073 kgha-1). For average mean yield from overall location, high yield obtained from Hawassa dume (2129 kgha-1) and Nasir (2002 kgha-1) followed by Sari (1989 kgha-1). Results revealed that Hawassa dume, Nasir and Sari were best performed and better adapted varieties than the others respectively. Therefore, the above mentioned varieties are promising varieties for the production area and recommendable for area with similar agro-ecologies. Keywords: Phaseolus Vulagris L, Evaluation, Grain yield,Varieties

Microbiological quality of filled pasta in relation to the nature of heat treatment.

The microbial population present in 49 samples of Italian industrially processed filled pasta was characterized and its changes during refrigerated storage were evaluated. The most frequently isolated species belonged to the genus Bacillus. No pathogenic organisms were isolated from the processed industrial pasta. As a consequence of the diversity of composition and thermal treatment a wide variability was observed (from less than 3 days to more than 1 month) in the shelf life at 4 degrees C of the industrial "fresh filled pasta." However, the results obtained suggested that the shelf life of the processed products depend not only on the number of surviving cells but also on the textural or microstructural changes induced by the heat treatment. Challenge tests using Staphylococcus aureus showed that even pasteurization values (P 70(10), expressed as an equivalent process time, in minutes, necessary to obtain at 70 degrees C the same lethal effect as during the actual process) not exceeding 2 were able to remarkably reduce the cell load of this organism. Subsequent growth of the surviving S. aureus cells occurred only at temperatures > 7 degrees C, particularly when the water activity (aw) values were higher than 0.97

Suitability of the nisin Z-producer lactococcus lactis subsp. lactis CBM 21 to be used as an adjunct culture for squacquerone cheese production

This research investigated the technological and safety effects of the nisin Z producer Lactococcus lactis subsp. lactis CBM 21, tested as an adjunct culture for the making of Squacquerone cheese in a pilot-scale plant. The biocontrol agent remained at a high level throughout the cheese refrigerated storage, without having a negative influence on the viability of the conventional Streptococcus thermophilus starter. The inclusion of CBM 21 in Squacquerone cheesemaking proved to be more effective compared to the traditional one, to reduce total coliforms and Pseudomonas spp. Moreover, the novel/innovative adjunct culture tested did not negatively modify the proteolytic patterns of Squacquerone cheese, but it gave rise to products with specific volatile and texture profiles. The cheese produced with CBM 21 was more appreciated by the panelists with respect to the traditional one

Alloying effects on the critical layer thickness in InxGa1−xAs/InP heterostructures analyzed by Raman scattering

International audienceRaman scattering has been used to estimate the critical layer thickness and to analyze the alloying effect on strain relaxation in InxGa1−xAs layers grown by molecular beam epitaxy on InP [001]-oriented substrate, for x ranging from 0.0 to 1.0. Measurements of longitudinal optical GaAs-like phonon frequency and Raman linewidth showed that the indium/gallium ratio contents greatly influences the strain relaxation. A comparison between Raman and x-ray diffraction measurements of relaxation ratios as a function of layer thickness is presented. The results can be explained in terms of the combined effect of strain and chemical and structural disorder

Human Breast Milk: A Source of Potential Probiotic Candidates

This study focuses on the isolation of lactobacilli/bifidobacteria from human breast milk and their first characterization, in the perspective to find new probiotic candidates to be included in food products. More specifically, breast-milk-isolated strains demonstrated a very good aptitude to adhere to intestinal cells, in comparison with L. rhamnosus GG strain, taken as reference. The same behavior has been found for hydrophobicity/auto-aggregation properties. A remarkable antagonistic activity was detected for these isolates not only against spoilage and pathogenic species of food interest, but also against the principal etiological agents of intestinal infections. Indeed, isolated strains impaired spoilage and pathogenic species growth, as well as biofilm formation by gut pathogens. In addition, breast milk strains were characterized for their antibiotic susceptibility, displaying species-specific and strain-specific susceptibility patterns. Finally, to assess their technological potential, the fermentation kinetics and viability of breast milk strains in pasteurized milk were investigated, also including the study of the volatile molecule profiles. In this regard, all the strains pointed out the release of aroma compounds frequently associated with the sensory quality of several dairy products such as acetic acid, diacetyl, acetoin, acetaldehyde. Data here reported point up the high potential of breast-milk-isolated strains as probiotics

Unravelling the functional and technological potential of soy milk based microencapsulated Lactobacillus crispatus and Lactobacillus gasseri

The main aim of this study was to evaluate the potential of microencapsulation with soy milk as a carrier, conducted by spray-drying, on three mixed cultures of functional vaginal lactobacilli, Lactobacillus crispatus (BC1, BC3, and BC4) and Lactobacillus gasseri BC9, that could be further exploited as an adjunct in health foods. The i) physicochemical properties (using scanning electronic microscopy), ii) viability of encapsulated bacteria over time, and iii) functional features of powders containing the encapsulated bacteria were characterised considering different storage conditions. All microbial mixtures exhibited high viability for 90 d of storage, regardless of the storage conditions. All microencapsulated microbial combinations, excluding L. crispatus BC3 + L. gasseri BC9, exhibited hydrophobicity values exceeding 60%. Moreover, regardless of the considered combination, the in vitro digestion results exhibited a more significant decrease in cell viability for non-encapsulated microbial combinations than that of the encapsulated strains

Chinese Studies at Ca’ Foscari. Lionello Lanciotti, Mario Sabattini and Their Legacy

The successful development of Chinese Studies at Ca’ Foscari was mainly due to the contribution of two eminent sinologists, Professor Lionello Lanciotti (1925-2015) and Professor Mario Sabattini (1944-2017). This paper offers a brief overview of their intellectual and academic experience in Venice and of their legacy