Wild Lactobacillus casei Group Strains: Potentiality to Ferment Plant Derived Juices

Plant derived beverages have recently gained consumers’ interest, particularly due to their intrinsic functional properties. They can also act as non-dairy carriers for probiotics and prebiotics, meeting the needs of lactose allergic/intolerant people and vegans. Direct fermentation of fruit and vegetables juices by probiotic lactic acid bacteria could be a tool to increase safety, shelf-life, nutrients bioavailability and to improve sensorial features of plant derived juices. This study aims to screen wild Lactobacillus casei-group strains isolated from dairy matrices for probiotic features, such as acid and bile salts resistance, and test them for the potentiality to ferment celery and orange juices. Strains’ ability to produce exopolysaccharides (EPS) in situ is also checked. These evaluations were performed for the first time in fruit and vegetables matrices by means of an impedometric analysis, recently shown to be a suitable and rapid method to measure microorganisms’ growth, acidification performances and EPS production. This study allowed the selection of three potentially probiotic L. casei-group wild strains able to ferment fruit and vegetable juices and also producing EPS. These strains with three-in-one abilities could be used to produce new functional fermented plant derived juices

Eating fermented: Health benefits of lab-fermented foods

Lactic acid bacteria (LAB) are involved in producing a considerable number of fermented products consumed worldwide. Many of those LAB fermented foods are recognized as beneficial for human health due to probiotic LAB or their metabolites produced during food fermentation or after food digestion. In this review, we aim to gather and discuss available information on the health-related effects of LAB-fermented foods. In particular, we focused on the most widely consumed LAB-fermented foods such as yoghurt, kefir, cheese, and plant-based products such as sauerkrauts and kimchi

Study on lipid fractions of Streptococcus thermophilus by TLC, GC and GC/MS techniques

In this research the lipid fraction of two strains of Streptococcus thermophilus was studied. Lipids were extracted by applying Folch method and fractioned by thin layer chromatography (TLC). Fatty acid composition was determined both before TLC, on the total fat extracted, and after TLC on diacylglycerol and apolar fractions. Gas chromatographic analysis was performed by using both flame ionization (FID) and mass spectrometer (MS) detector. The main difference between the two strains was the presence of short and medium chain fatty acids in food-born S. thermophilus. Moreover one of the most important bacterial fatty acids, C19 cyclopropane, was detected only in diacylglycerols, which, as reported in literature, are formed transiently as intermediates in the biosynthesis of glycerophospholipids

Atp bioluminescence for rapid and selective detection of bacteria and yeasts in wine

Microbial contamination may represent a loss of money for wine producers as several defects can arise due to a microorganism’s growth during storage. The aim of this study was to implement a bioluminescence assay protocol to rapidly and simultaneously detect bacteria and yeasts in wines. Different wines samples were deliberately contaminated with bacteria and yeasts at different concentrations and filtered through two serial filters with decreasing mesh to separate bacteria and yeasts. These were resuscitated over 24 h on selective liquid media and analyzed by bioluminescence assay. ATP measurements discriminated the presence of yeasts and bacteria in artificially contaminated wine samples down to 50 CFU/L of yeasts and 1000 CFU/L of bacteria. The developed protocol allowed to detect, rapidly (24 h) and simultaneously, bacteria and yeasts in different types of wines. This would be of great interest for industries, for which an early detection and discrimination of microbial contaminants would help in the decision‐making proces

Interacting Preformed Cooper Pairs in Resonant Fermi Gases

We consider the normal phase of a strongly interacting Fermi gas, which can have either an equal or an unequal number of atoms in its two accessible spin states. Due to the unitarity-limited attractive interaction between particles with different spin, noncondensed Cooper pairs are formed. The starting point in treating preformed pairs is the Nozi\`{e}res-Schmitt-Rink (NSR) theory, which approximates the pairs as being noninteracting. Here, we consider the effects of the interactions between the Cooper pairs in a Wilsonian renormalization-group scheme. Starting from the exact bosonic action for the pairs, we calculate the Cooper-pair self-energy by combining the NSR formalism with the Wilsonian approach. We compare our findings with the recent experiments by Harikoshi {\it et al.} [Science {\bf 327}, 442 (2010)] and Nascimb\`{e}ne {\it et al.} [Nature {\bf 463}, 1057 (2010)], and find very good agreement. We also make predictions for the population-imbalanced case, that can be tested in experiments.Comment: 10 pages, 6 figures, accepted version for PRA, discussion of the imbalanced Fermi gas added, new figure and references adde

Modelling aspects of terrestrial ecology in an italian endemic salamander, Salamandrina perspicillata

Density and other aspects of terrestrial activity were studied in a population of Salamandrina perspicillata from central Italy (Vejo Natural Park, province of Rome). Salamander density was studied by line-transect methodology with Distance modelling procedures. Linear distance of each salamander from water was also measured, as well as the correlations between population density, distance of salamanders from water, and some habitat variables. In total, a sample of 227 captures was collected and analysed. The distance of salamanders from water increased significantly with time (number of days after the beginning of the study, i.e. 13 April), considering either as dependent variable the mean distance of salamanders on each day of survey or the individual distances recorded for all the salamanders captured during the present investigation. After subdividing the stream into various sectors classifi ed on the basis of their morphological and habitat variables, a General Linear Model (full factorial design) showed that the salamander distance from water varied significantly among sectors of the stream, with also an effect of time elapsed since the first day of survey and an effect of stream sector*time. Estimated density varied remarkably with day-of-survey, ranging from 0 to over 55 individuals/ha. The mean density of salamanders was 24.6 ± 14.7 individuals/ha, similar to that of many other salamander species studied so far. According to both multivariate analyses and logistic regression models, two habitat variables (inclination of the slopes surrounding the stream and type of stream banks) significantly affected the population densityModélisation d'aspects de l'écologie terrestre d'une salamandre endémique italienne, Salamandrina perspicillata.- La densité et d'autres aspects de l'activité terrestre ont été étudiés dans une population de Salamandrina perspicillata du centre de l'Italie (parc naturel de Vejo, province de Rome). La densité des salamandres a été établie par la méthode des line-transects avec le logiciel Distance. La distance à l'eau de chaque individu a également été mesurée ainsi que les corrélations entre densité de population, distance à l'eau et diverses variables de l'habitat. Au total, un échantillon de 227 captures a été obtenu et analysé. La distance à l'eau s'est avérée croître significativement avec le temps (nombre de jours à partir du début de l'étude, c-à-d. le 13 avril), que l'on prenne tant comme variable indépendante la distance moyenne des individus établie chaque jour du suivi que les distances individuelles de toutes les salamandres enregistrées durant l'étude. Après subdivision du cours d'eau en secteurs classés en fonction de leur morphologie et de leurs variables d'habitat, un modèle général linéaire a montré que la distance à l'eau variait de manière significative entre les secteurs, avec aussi un effet temps écoulé depuis le premier jour de suivi et un effet secteur x temps. La densité estimée variait de manière remarquable de 0 à plus de 55 individus/ha selon le jour de suivi. La densité moyenne était de 24,6 ± 14,7 individus/ha, similaire à celle de beaucoup d'autres espèces de salamandres étudiées jusqu'à présent. Tant des analyses multivariées que des modèles de régression logistique ont montré que deux variables d'habitat (l'inclinaison des pentes entourant le cours d'eau et le type de bord du cours d'eau) affectaient de manière significative la densité de population

Interaction of metal phthalocyanines with carbon zigzag and armchair nanotubes with different diameters

Quantum-chemical calculations of the association of metal free, cobalt, copper and zinc phthalocyanines (MPc) with carbon zigzag and armchair nanotubes (CNTs) with diameters in the range of 7–14 Å were carried out by the DFT method with the use of BH van der Waals density functional and DZP atomic basis set. It was shown that interaction energy between the phthalocyanine molecules and the CNTs, as a whole, increases with an increase of the diameter of carbon nanotubes. However, in the case of CNT(n,0) the energy reaches its maximal value at n = 16 or 17 depending on the central metal atom and phthalocyanine orientation on the carbon nanotubes surface. Up to diameter of 10.5 Å of the CNTs, stronger binding of the considered MPc macrocyclic molecules is observed with carbon armchair nanotubes. However, in the case of higher diameters the phthalocyanines are associated more strongly with the zigzag CNTs

Diets including Animal Food Are Associated with Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a clinical condition with a prevalence of up to 25% in Western countries. Typical GERD symptoms include heartburn and retrosternal regurgitation. Lifestyle modifications, including diet, are considered a first-line therapeutic approach. To evaluate the impact of life habits on GERD in this cross-sectional study, we used data collected through an online survey from 1146 participants. GERD was defined according to the Montreal Consensus. For all participants, clinical and lifestyle characteristics were recorded. Overall, 723 participants (63.1%) consumed a diet including animal food (non-vegans), and 423 participants (36.9%) were vegans. The prevalence of GERD was 11% (CI 95%, 9–14%) in non-vegans and 6% (CI 95%, 4–8%) in vegans. In the multivariate analysis, after adjusting for confounding factors, subjects on a non-vegan diet were associated with a two-fold increase in the prevalence of GERD compared to vegans (OR = 1.96, CI 95%, 1.22–3.17, p = 0.006). BMI and smoking habits were also significantly associated with GERD. This study shows that an animal food-based diet (meat, fish, poultry, dairy, and eggs) is associated with an increased risk of GERD compared to a vegan diet. These findings might inform the lifestyle management of patients with GERD-related symptoms

Lysozyme affects the microbial catabolism of free arginine in raw-milk hard cheeses

Lysozyme (LZ) is used in several cheese varieties to prevent late blowing which results from fermentation of lactate by Clostridium tyrobutyricum. Side effects of LZ on lactic acid bacteria population and free amino acid pattern were studied in 16 raw-milk hard cheeses produced in eight parallel cheese makings conducted at four different dairies using the same milk with (LZ\ufe) or without (LZ-) addition of LZ. The LZ-cheeses were characterized by higher numbers of cultivable microbial population and lower amount of DNA arising from lysed bacterial cells with respect to LZ \ufe cheeses. At both 9 and 16 months of ripening, Lactobacillus delbrueckii and Lactobacillus fermentum proved to be the species mostly affected by LZ. The total content of free amino acids indicated the proteolysis extent to be characteristic of the dairy, regardless to the presence of LZ. In contrast, the relative patterns showed the microbial degradation of arginine to be promoted in LZ \ufe cheeses. The data demonstrated that the arginine-deiminase pathway was only partially adopted since citrulline represented the main product and only trace levels of ornithine were found. Differences in arginine degradation were considered for starter and non-starter lactic acid bacteria, at different cheese ripening stages

Macroscopic transport by synthetic molecular machines

Nature uses molecular motors and machines in virtually every significant biological process, but demonstrating that simpler artificial structures operating through the same gross mechanisms can be interfaced with—and perform physical tasks in—the macroscopic world represents a significant hurdle for molecular nanotechnology. Here we describe a wholly synthetic molecular system that converts an external energy source (light) into biased brownian motion to transport a macroscopic cargo and do measurable work. The millimetre-scale directional transport of a liquid on a surface is achieved by using the biased brownian motion of stimuli-responsive rotaxanes (‘molecular shuttles’) to expose or conceal fluoroalkane residues and thereby modify surface tension. The collective operation of a monolayer of the molecular shuttles is sufficient to power the movement of a microlitre droplet of diiodomethane up a twelve-degree incline.