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The post-weaning period is a stressful process for piglets with compromised gut health, increasing susceptibility to diarrhea and infection. Oxygen concentration in the gut affects microbiome and fermentation profile. Live yeasts have been used to promote gut health and performance of young animals. An experiment was carried out to determine the influence of live yeast on gut conditions including redox potential, microbial composition, and short chain fatty acid (SCFA) production of piglets. Sixteen Pietrain *(Landrace*Large White) piglets were distributed into blocks by live weight and allocated at 4 per pen for a 28-d trial. Each block was composed by a combination of the 2 dietary treatments corresponding to a control diet and a diet supplemented with live yeast (1 kg/tonne Vistacell, AB Vista). At the end of trial, piglets were euthanized to measure kinetics of redox potential (Eh) and pH from caecum until 35 min post-mortem. Then, digesta samples from stomach, duodenum, jejunum, ileum, caecum, and rectum were collected for microbial composition and SCFA production. Data were analyzed using GLM procedure of SAS 9.4 and means compared with a Student-Newman-Keuls test. Redox potential decreased with time (P < 0.001) until stabilizing after 20 min, and a clear difference was observed between treatments (P < 0.001). Supplemented live yeast survives throughout gastrointestinal tract and modifies microbial populations enhancing lactic acid bacteria (P < 0.001) while reducing enterobacteria (P < 0.001) or eliminating fungi (P < 0.001). The production of SCFA from caecum digesta was 3-fold higher than in ileum with significantly different molar proportion of individual SCFA. Lactic, formic, and acetic acids predominate on ileum (> 93%) whereas acetic, propionic, and butyric dominate on caecum digesta (> 90%). Nevertheless, no differences were observed due to dietary treatments. In conclusion, live yeast supplementation of diets modifies redox conditions prevailing in the gut modifying microbial populations and helping piglets to overcome post-weaning growth check.

The EC 2019/187 shows the rules for the usage of ethyl alcohols to fortify wines. These must be obtained from products derived from agriculture and the use of alcohols of mineral or chemical origin is not authorized. The ethyl alcohols authorized for the fortification in the D.O. Sherry have wine origin. But, there are other alcohols that could be equally productive and at a lower economic cost, such as beet or sugar cane alcohol. The effect that different types of ethyl alcohols may have on the yeasts of flor remains unknown. Our goal was to analyze the effects of other alcohols (beet, sugar cane, etc.) on the development of the veil of flor. In this way, the yeasts that constitute the veil of flor of Fino wines were isolated and identified by microbiological techniques and characterized by molecular tools and by biochemical and microbiological tests such as cellular hydrophobicity, flocculation, acetic acid production, etc. Then, base wines were fortified with different distilled alcohols, such as malt brandy, tequila, among others. Biological aging under the veil of flor was monitored to later determine the volatile fractions. Alcohol from sugar cane could be a promising alternative to fortify Fino wines.

The objective was to evaluate the effects of feeding a stimbiotic, Signis (AB Vista), and fiber source, sugar beet pulp or wheat bran, on nursery performance. Pigs (n = 480; 5.87±1.10 kg) were assigned to treatments in a 2 x 3 factorial arrangement of Stimbiotic (0 or 100 mg/kg) and Fiber Source (control, sugar beet pulp, or wheat bran). For phase 1, wheat bran and sugar beet pulp were added at 6.0% and 3.5%, respectively. For phase 2, wheat bran and sugar beet pulp were added at 10% and 6.0%, respectively. There were 8 pens containing 10 pigs per treatment group. A 2-phase feeding program lasting 3 weeks each was used. Performance was monitored for 6 weeks. Fecal scores were recorded, and fecal samples were collected to determine apparent total tract nutrient (ATTD) digestibility. Full value pigs (FVP) were determined by subtracting mortality and removals from total number placed. Pen gain was calculated as difference of sum of BW at d 42 minus sum of BW at d 0. Data were analyzed by ANOVA using the fit model platform in JMP. Significance was accepted at P ≤ 0.05 and trends at P < 0.10. Phases 1 and 2 ADG, ADFI, gain:feed or d42 BW did not differ between treatment groups. There were effects of Stimbiotic and Fiber Source on FVP as there were increased FVP (P < 0.05) with Stimbiotic and decreased FVP (P < 0.05) for pigs fed wheat bran. Pen gain tended to increase (P = 0.06) in pigs fed Stimbiotic and was decreased (P < 0.05) for pigs fed wheat bran. Mean fecal scores were not affected by Fiber Source, but tended (P = 0.07) to be reduced by Stimbiotic. Stimbiotic tended (P ≤ 0.09) to increase ATTD of dry matter and energy. In conclusion, feeding a stimbiotic increased FVP, while feeding wheat bran decreased FVP. Further research is needed to explore the effects of fiber source in nursery diets and how it interacts with Stimbiotic.

IntroductionConventional or biologic disease-modifying anti-rheumatic drugs (DMARDs) are the mainstay of treatment for systemic autoimmune disease (SAD). Infectious complications are a major concern in their use.ObjectiveTo evaluate the clinical benefit of sublingual mucosal polybacterial vaccines (MV130 and MV140), used to prevent recurrent respiratory and urinary tract infections, in patients with SAD and secondary recurrent infections following conventional or biologic DMARDs.MethodsAn observational study in SAD patients with recurrent respiratory tract infections (RRTI) and/or recurrent urinary tract infections (RUTI) was carried out. All patients underwent mucosal (sublingual) vaccination with MV130 for RRTI or with MV140 for RUTI daily for 3 months. Clinical evaluation was assessed during 12 months of follow-up after the first dose, i.e., 3 months under treatment and 9 months once discontinued, and compared with the previous year.ResultsForty-one out of 55 patients completed 1-year follow-up. All patients were on either conventional or biologic DMARDs. A significant decrease in the frequency of RUTI (pS. pneumoniaeIgA and IgG antibodies following MV130 vaccination.ConclusionsSublingual polybacterial vaccines prevent recurrent infections in patients with SAD under treatment with immunosuppressant therapies, supporting a broad non-specific anti-infectious effect in these patients.

Infectious complications are a major cause of morbidity and mortality in B-cell hematological malignancies (HM). Prophylaxis for recurrent infections in HM patients with antibody deficiency consists of first-line antibiotics and when unsuccessful, gammaglobulin replacement therapy (IgRT). Recent knowledge of trained immunity-based vaccines (TIbV), such as the sublingual polybacterial formulation MV130, has shown a promising strategy in the management of patients with recurrent infections. We sought to determine the clinical benefit of MV130 in a cohort of HM patients with recurrent respiratory tract infections (RRTIs) who underwent immunization with MV130 for 3 months. Clinical information included the frequency of infections, antibiotic use, number of visits to the GP and hospitalizations previous and after MV130 immunotherapy. Improvement on infection rate was classified as: clear (>60% reduction of infection), partial (26%–60%) and low (≤25%) improvement. Fifteen HM patients (aged 42 to 80 years; nine females) were included in the study. All patients reduced their infection rate. Analysis of paired data revealed that the median (range, min - max) of respiratory infectious rate significantly decreased from 4.0 (8.0–3.0) to 2.0 (4.0–0.0) (pp = 0.002) during 12 months after initiation of treatment with MV130. The number of infectious-related GP or emergency room visits declined from 4.0 (8.0–2.0) to 2.0 (3.0–0.0) (pp = 0.032). Regarding safety, no adverse events were observed. On the other hand, immunological assessment of serum IgA and IgG levels demonstrated an increase in specific antibodies to MV130-contained bacteria following MV130 immunotherapy. In conclusion, MV130 may add clinical benefit reducing the rate of infections and enhancing humoral immune responses in these vulnerable patients.

Farrowing and lactation periods require a high demand for nutrients. Superdose (≥1500 FTU/kg) of phytase may increase the nutritive value of diets and improve litter performance. The objective of this study was to determine whether the superdosing of phytase (Quantum Blue; AB Vista) in the peripartum diet affects sow and piglet productivity and serum biomarkers (urea, cortisol, and calcium). A total of 54 sows, Topigs TN70 (27 control group, 27 superdosing group) were blocked by parity and randomly assigned to the treatments. The control lactation diet was a mixed-cereal and soybean meal-based, formulated to meet sow’s requirement with 500 FTU/kg phytase inclusion. The superdosing diet, was supplemented with a further 2,000 FTU/kg phytase to give a total of 2,500 FTU/kg. Peripartum treatment diets were provided from 10 d before farrowing until 10 d after, after which a common standard lactation was fed. Piglets were weaned at 26 d of age. Data were analyzed with ANOVA evaluating the effects of phytase dose and parity using the fit model platform in JMP15.1. Significant treatment means were separated using Student’s t-tests, with significance accepted at P ≤ 0.05. Birth weights of piglets were significantly affected by parity, with piglets born from parity 1 or 4+ sows being around 180g lighter in weight (P < 0.01) than piglets born from parity 2 or 3. The superdosing treatment increased piglet weight at weaning by 490g/weaned piglet (P < 0.01). Cortisol levels were greater (3.7 vs. 1.3 µg/dl, P < 0.01) at farrowing compared with 10d post-farrowing. Urea concentrations were 37% higher in the superdosing treatment at farrowing compared with control (P = 0.02). It can be concluded that the use of phytase at superdosing levels can be used in peripartum diets to improve piglet weight gain during lactation which is linked with greater utilization of nutrients that has been associated with greater phytate breakdown.

The structural organization of chromosomes is a crucial feature that defines the functional state of genes and genomes. The extent of structural changes experienced by genomes of eukaryotic cells can be dramatic and spans several orders of magnitude. At the core of these changes lies a unique group of ATPases –the SMC proteins– that act as major effectors of chromosome behavior in cells. The Smc5/6 proteins play essential roles in the maintenance of genome stability, yet their mode of action is not fully understood. Here we show that the human Smc5/6 complex recognizes unusual DNA configurations and uses the energy of ATP hydrolysis to promote their compaction. Structural analyses reveal subunit interfaces responsible for the functionality of the Smc5/6 complex and how mutations in these regions may lead to chromosome breakage syndromes in humans. Collectively, our results suggest that the Smc5/6 complex promotes genome stability as a DNA micro-compaction machine.

In this paper we present interconnection and damping assignment passivity-based control (IDA-PBC) applied to a 2 degrees of freedom (DOFs) underactuated gyroscope. First, the equations of motion of the complete system (3-DOF) are presented in both Lagrangian and Hamiltonian formalisms. Moreover, the conditions to reduce the system from a 3-DOF to a 2- DOF gyroscope, by using Routh’s equations of motion, are shown. Next, the solutions of the partial differential equations involved in getting the proper controller are presented using a reduction method to handle them as ordinary differential equations. Besides, since the gyroscope has no potential energy, it presents the inconvenience that neither the desired potential energy function nor the desired Hamiltonian function has an isolated minimum, both being only positive semidefinite functions; however, by focusing on an open-loop nonholonomic constraint, it is possible to get the Hamiltonian of the closed-loop system as a positive definite function. Then, the Lyapunov direct method is used, in order to assure stability. Finally, by invoking LaSalle’s theorem, we arrive at the asymptotic stability of the desired equilibrium point. Experiments with an underactuated gyroscopic mechanical system show the effectiveness of the proposed scheme.

Utilizing different dietary fiber sources has been studied in piglets to help mitigate post-weaning diarrhea and improve post-weaning performance. An experiment was conducted to investigate the effect of adding sugar beet pulp or a stimbiotic (Signis; AB Vista) on nursery pig performance. Barrows (n = 216; average initial BW = 5.1kg) were randomly allotted to one of three dietary treatments and fed a 4 phase feeding program; 1) Control (Con), Insoluble/Soluble fibre ratio (I/S), P1; 4.47, P2; 5.84, P3; 5.82, P4; 7.08. 2) High Soluble (HS) with sugar beet pulp added at 5% (P1 and P2) and 2.5% (P3 and P4) giving the following I/S ratio; P1; 2.63, P2; 2.91, P3; 5.02 and P4; 5.42. 3) Control plus stimbiotic added at 100 g/t (SIG). Pen weight and feed disappearance were recorded weekly to calculate ADG, ADFI, and G:F. Fecal score was visually ranked by pen daily from wean to 35 days. Blanket water medications were not provided. Instead, individual pigs that needed treatment were identified and injected with individual antibiotic interventions, and the number of interventions per pig was recorded. Performance data were submitted to ANOVA using JMP with mean separation by Tukey test and a contingency analysis was used to compare antibiotic injections. At day 14, pigs had a Rotavirus A and B challenge. Addition of HS or SIG reduced (P < 0.05) individual antibiotic treatments by 56 and 32% compared to the CON, respectively. No differences were observed in scour scores or overall ADG. Overall intake was greater (P < 0.01) in HS (0.560 kg) than CON (0.491 kg) or SIG (0.492 kg). Pigs fed SIG (0.671) had a better (P = 0.011) G:F over SBP (0.602), with CON (0.649) being intermediate. In conclusion, HS increased intake where stimbiotic improved feed efficiency, and both decreased antibiotic treatments.

Cecal inoculum collected from broilers fed a diet supplemented with xylanase showed increased gas production in an in vitro fermentation study with arabinoxylan-based substrates, indicating that intestinal microbiota can adapt to increase the capability to ferment arabinoxylans when pre-exposed to xylo-oligosaccharides (XOS) produced by xylanase. As the most abundant non-starch polysaccharides in a corn-soybean meal-based diet is arabinoxylan, this study tested the hypothesis that a blend of a xylanase and XOS will improve growth performance of pigs compared with those fed a diet supplemented with xylanase alone. One hundred twenty male crossbred (Landrace x Large white x Duroc) pigs (77 days average age; 30 kg average body weight -BW) were allocated to one of three treatments: CTR (control diet), XYL (CTR diet supplemented with 100 g/t of xylanase [Econase XT, AB Vista]) and XYL+XOS [CTR diet supplemented with 100 g/t of xylanase and XOS (Signis, AB Vista)]. Each treatment had ten replicates, with 4 animals each. The control diet was formulated with corn, soybean meal, DDGS and cassava meal as major ingredients. Pelleted diets were fed over 3 phases: grower (30–60 kg), finisher 1 (60–80 kg) and finisher 2 (80–100 kg). Average daily gain (ADG) and daily feed intake (ADFI) were measured from 30 to 100 kg and feed efficiency calculated (FCR). No treatment effects were observed on ADFI. Pigs offered the XYL+XOS had increased ADG (CTR = 1.058 vs XYL+XOS= 1.086 g/pig/d; P = 0.02) compared with those supplemented with xylanase alone (CTR = 1.058 vs XYL = 1.067 g/pig/d; P = 0.40). Feed efficiency was improved with XYL (2.65; P = 0.042) and XYL+XOS (2.60; P < 0.001) compared with CTR (2.71). These results suggest that xylanase in combination with XOS further improves daily gain and FCR compared with a xylanase alone. Interestingly the differences between XYL and XYL+XOS become more apparent in older animals, when the microbiome matures and possibly digests fiber more effectively.

Acetic and some lactic acid bacteria are the main reason for the loss of quality of musts and wines, giving rise to defects such as “vinegary”, “chopped” or preventing alcoholic and / or malolactic fermentation. The solution to this problem consists in the application of authorized bactericidal agents, such as sulfurous. The aim of this work is to isolate bacteriophages from musts and wines of different grape varieties, able to eliminate lactic and acetic acid bacteria spoilages. Musts obtained from grape-berries of Vitis vinifera cv. Chardonnay and Moscatel and a red wine made with the Tintilla de Rota variety were used to isolate bacteriophages. It were isolated by classical virology methods and identified by electron microscopy. Host bacteria used in the study were the lactic acid bacteria of the species Lactobacillus hilgardii, L. plantarum and Oenococcus oeni and the acetic bacteria Acetobacter aceti. A comparative study was performed on musts and wines, previously inoculated with bacteria, by phage titration and SO2 addition to study the effectiveness of bacteriophages against bacteria. Bacteriophages were obtained from all musts and wine, belonging to the order of Caudovirals and Tectivirals. The comparative study showed that a cocktail of bacteriophages at low concentration is as effective as sulfur.

The breakdown of long chain arabinoxylans into smaller chain xylo-oligomers by the use of xylanase results in a shift towards fiber utilizing bacteria resulting in production of small chain fatty acids and improved pig performance. The objective of this study was to evaluate the effect of xylanase (Econase XT; AB Vista) on finisher pig performance. A total of 598 pigs; (37.4 ± 1.0 kg) were fed a single-phase diet for 60 days. Pigs were assigned to two treatments; 0 (CTL) or 16,000 BXU/kg of xylanase (XYL) with 12 pen replicates and 24/25 pigs (mixed sex; gilts and boars) per treatment. The diet was based on wheat, barley, soybean meal, rapeseed meal, and wheat midds; SID Lys: 0.88%, NDF: 14.7%, and NE: 2090 kcal/kg. Average daily gain (ADG), feed intake (ADFI) and feed conversion ratio (FCR) were evaluated in phase 1 (0-26d), phase 2 (26-60d) and overall (0-60d). Liveability was measured per treatment. Data were analysed using JMP 12 using the standard least square platform and ANOVA was performed to determine significance at P < 0.05. The model included initial BW as a covariant. The results indicated that there was no effect of xylanase on liveweight, ADG or ADFI at any phase of the finisher period. The use of xylanase improved FCR in phase 2 (2.53 v 2.60: P < 0.05) and overall (2.44 v 2.49 P=0.03). No differences were seen in liveability (CTL; 96%; XYL 98%; P = 0.29). It can be concluded that the use of xylanase can be used in finisher feeds to improve FCR which is linked with greater energy utilisation that has been associated with greater fiber breakdown through xylanase use.

The extensive use of synthetic fertilizers and pesticides has negative consequences in terms of soil microbial biodiversity and environmental contamination. Faced with this growing concern, a proposed alternative agricultural method is the use of microorganisms as biofertilizers. Many works have been focused on bacteria, but the limited literature on yeasts and their potential ability to safely promote plant growth is gaining particular attention in recent years. Thus, the objective of this review is to highlight the application of yeasts as biological agents in different sectors of sustainable agricultural practices through direct or indirect mechanisms of action. Direct mechanisms include the ability of yeasts to provide soluble nutrients to plants, produce organic acids and phytohormones (indole-3-acetic acid). Indirect mechanisms involve the ability for yeasts to act as biocontrol agents through their high antifungal activity and lower insecticidal and herbicidal activity, and as soil bioremediating agents. They also act as protective agents against extreme environmental factors by activating defense mechanisms. It is evident that all the aspects that yeasts offer could be useful in the creation of quality biofertilizers and biopesticides. Hence, extensive research on yeasts could be promising and potentially provide an environmentally friendly solution to the increased crop production that will be required with a growing population.

Fino wine is one of the most important Sherry wines and it is obtained through a complex and dynamic biological aging system. In this study, wine and veil of flor samples from fifty-two barrels with different aging levels and distributed in three different wineries from the Jerez-Xeres-Sherry winemaking area have been analyzed during two years. Some of the wine compounds most deeply involved in flor yeast metabolism were analyzed to take into account the blending effect of this system. On the other hand, veil of flor was analyzed by molecular methods, finding five different species: S. cerevisiae, W. anomalus, P. membranaefaciens, P. kudriavzevii and P. manshurica, being the first time that the three last species have been reported in this biological aging system. Since S. cerevisiae was the vast majority of the isolates, its intraspecies variability was also analyzed by the simultaneous amplification of three microsatellite loci, obtaining nine different S. cerevisiae genotypes, also differentiated according to their physiological properties. Biodiversity analysis showed there were significant differences between the three wineries in the three aging scales, although the overall diversity was relatively low. Moreover, variations in the relative frequency of the different S. cerevisiae genotypes were found to be seasonal-dependent.

This study investigated whether the inclusion of a stimbiotic (STB) can improve performance, influence intestinal microbiota and fermentation activity, and reduce pro-inflammatory cytokines in piglets fed a low zinc oxide diet without antimicrobial growth promotors compared to fructo-oligosaccharide (FOS) and mannan-oligosaccharide (MOS) when housed either in good sanitary (GS) or poor sanitary (PS) environments. One hundred forty-four male pigs (28-day-old) were sorted by initial body weight (BW) and allocated to one of six experimental treatments: 1) GS environment without any additive (GS-CTR); 2) GS environment with 0.01% stimbiotic (GS-STB); 3) PS environment (without cleaning and disinfection of a previously populated room) without any additive (PS-CTR); 4) PS environment with 0.01% STB (PS-STB); 5) PS environment with 0.1% MOS (PS-MOS); and 6) PS environment with 0.2% FOS (PS-FOS). Each treatment had six replicates, with four animals each. Three feeding phases, based on corn, wheat, and soybean meal were available ad libitum for the 42-days of the study. Housing piglets under PS conditions negatively influenced performance, increased plasma tumor necrosis factor alpha (TNF-α), affected the fecal microbial populations and increased concentrations of branched-chain fatty acids (BCFA) compared to GS. Stimbiotic improved 42-d-BW under PS conditions (P < 0.05) whereas MOS or FOS had no effect. On d35, plasma TNF-α was reduced with STB in PS (P < 0.05). The ratio between VFA:BCFA increased (P < 0.05) with STB, MOS or FOS in PS, and under GS condition, STB also increased the ratio. Stimbiotic increased the proportion of Clostridiales Family XIII Incertae Sedis and Clostridiaceae, while MOS and FOS increased Selenomonadaceae, Catabacteriaceae and Fibrobacteraceae. These results indicate that STB shifted the intestinal microbiome to favor fiber fermentation which likely contributed to reduced inflammatory response and improved performance, particularly in piglets reared in PS conditions.

Flexible AC transmission systems (FACTS) are a modern technology to increase controllability in power systems. This work presents an analysis of Interline Power Flow Controller (IPFC) which is a FACTS device. This device control and manage power flow in transmission lines. Supplementary damping controller is installed on IPFC Proportional Integral (PI) control. Power Oscillation Damping (POD) and Power System Stabilizers (PSS) contribute to power system stability. This works represents the electric power system and Interline Power Flow Controller FACTS device by a current sensitivity model (CSM). This work focuses on small-signal stability studies using an Adaptive Genetic Algorithm and Hyper-mutation (AGAH) to design simultaneously controller parameters. Adaptive Genetic Algorithm aims to find optimal controller parameters to enhance greatly stability of the power system. This paper considers two areas 14 bus symmetrical system in order to assess proposed algorithm. Simulations are carried out in MatLab platform in order to compare genetic algorithm with proposed algorithm performance. Results show AGAH outweighed AG by time convergence and accuracy.

Small-magnitude disturbances happen to produce electro-mechanical oscillations which should be damped as quickly as possible to ensure reliability and stability of electrical power system (EPS). Flexible AC transmission systems (FACTS) are a modern technology to increase controllability in power systems. This paper presents an analysis of Interline Power Flow Controller (IPFC), which is a FACTS device based on Voltage Source Controller (VSC). The electric power system and IPFC FACTS device get represented by a current sensitivity model (CSM). This work focuses on small-signal stability studies using an Adaptive Genetic Algorithm with Hyper-mutation (AGAH) for tuning Power System Stabilizers (PSS) and IPFC with Power Oscillation Damping (POD) controllers in a coordinated way. AGAH aims to find optimal controller parameters to enhance poor damping of local and inter-area low frequency oscillations. Two areas 14 bus symmetrical system is considered in order to assess proposed algorithm. Simulations are carried out in MatLab platform in order to compare genetic algorithm (GA) with proposed algorithm performance. Results show AGAH yields more accurate damping value and gets convergence faster than the simple GA.

The increasing level of hazardous residues in the environment and food chains has led the European Union to restrict the use of chemical fungicides. Thus, exploiting new natural antagonistic microorganisms against fungal diseases could serve the agricultural production to reduce pre- and post-harvest losses, to boost safer practices for workers and to protect the consumers' health. The main aim of this work was to evaluate the antagonistic potential of epiphytic yeasts against Botrytis cinerea, Aspergillus carbonarius, and Penicillium expansum pathogen species. In particular, yeast isolation was carried out from grape berries of Vitis vinifera ssp sylvestris populations, of the Eurasian area, and V. vinifera ssp vinifera cultivars from three different farming systems (organic, biodynamic, and conventional). Strains able to inhibit or slow the growth of pathogens were selected by in vitro and in vivo experiments. The most effective antagonist yeast strains were subsequently assayed for their capability to colonize the grape berries. Finally, possible modes of action, such as nutrients and space competition, iron depletion, cell wall degrading enzymes, diffusible and volatile antimicrobial compounds, and biofilm formation, were investigated as well. Two hundred and thirty-one yeast strains belonging to 26 different species were isolated; 20 of them, ascribed to eight species, showed antagonistic action against all molds. Yeasts isolated from V. vinifera ssp sylvestris were more effective (up to 50%) against B. cinerea rather than those isolated from V. vinifera ssp vinifera. Six strains, all isolated from wild vines, belonging to four species (Meyerozyma guilliermondii, Hanseniaspora uvarum, Hanseniaspora clermontiae, and Pichia kluyveri) revealed one or more phenotypical characteristics associated to the analyzed modes of antagonistic action.

Yeasts involved in veil formation during biological ageing of Sherry wines are mainly Saccharomyces cerevisiae, and they have traditionally been divided into four races or varieties: beticus, cheresiensis, montuliensis and rouxii. Recent progress in molecular biology has led to the development of several techniques for yeast identification, based on similarity or dissimilarity of DNA, RNA or proteins. In view of the latest yeast taxonomy, there are no more races. However, molecular techniques are not enough to understand the real veil-forming yeast diversity and dynamics in Sherry wines. We propose a reliable method, using a microtiter reader, to evaluate the fermentation and assimilation of carbon and nitrogen sources, the osmotolerance and the antibiotic resistance, using 18 S. cerevisiae and 5 non-Saccharomyces yeast strains, to allow correct identification and classification of the yeast strains present in the velum of flor complex.

Xylanases are commonly used to improve nutrient digestibility and performance in pig diets. Xylo-oligosaccharides (XOS) are degraded in the gut primarily by Bifidobacteria, leading to an increase in butyrate production. The objective of this study was to determine the effect of a blend of a xylanase and XOS (Signis, AB Vista) on growth performance and intestinal microbiota profile of weaning piglets. A total of 168 mixed sex PIC weaned piglets weighting between 4.5 and 6.7 kg (5.3 kg average weight) were allocated to 28 pens with 6 animals each and 14 pens per diet blocked by initial weight. Diets consisted of a control (based on corn-SBM) without and with 100 g/tonne Signis. The mash diets were fed over 2 phases: pre-starter (6-11 kg) and starter (11-25 kg). Feed samples were collected for xylanase activities analyses, and results were as expected. Liveability, average daily gain and feed intake were recorded, and feed conversion ratio (FCR) calculated. Colon digesta samples were collected after 6 weeks of Signis supplementation for bacterial identification through 16S rRBA rRNA (V3-V4) sequencing. Results are presented as the relative operational taxonomic units (OTU) values for each bacteria sequenced. Overall, inclusion of Signis reduced (P = 0.05) FCR by 9 points (1.79 vs. 1.88; SEM=0.025) at 42 days post-weaning. No differences in the OTU values were observed between treatments, with Firmicutes making up the largest proportion of the colon microbiota, followed by Actinobacteria and Proteobacteria. Bacteroidetes tended (P < 0.10) to be higher in the Signis group (0.06 vs 0.22; SEM=0.058). Piglets supplemented with Signis had a trend (P < 0.10) to have higher concentration of uncultured Clostridium spp, which are involved in the fermentation of fiber. This suggests that Signis stimulates the development of a fibrolytic microbiome and thus piglet performance.

Biological ageing occurs after fermentation of the grape must and it is due to the appearance of a biofilm on the surface of the wine called “veil of flor”. Yeast involved in veil formation are mainlySaccharomyces cerevisiaeand they have traditionally been divided into four races according to their ability to metabolize different sugars. The growth of flor yeasts depends on different factors, such as the aerobic assimilation of the wine ethanol, since the medium is deficient in both sugars and nitrogen. Actually, flor yeast metabolism is different from wineS. cerevisiaeyeast, but it hasn't been analysed yet. Thus, the aim of this work is to study the diversity of flor yeast strains and to analyse the composition and the structure of the veil of flor in Jerez-Xérés-Sherry D.O. The results of this work revealed 14 different genotypes ofS. cerevisiaestrains using multiplex-microsatellite PCR and these strains showed 8 different biochemical profiles using a similar procedure than traditionally. In addition, mannose and glucose were found in veil of flor complex using UHPLC-MS.

Adaptation to changes in osmolarity is fundamental for the survival of living cells, and has implications in food and industrial biotechnology. It has been extensively studied in the yeast Saccharomyces cerevisiae, where the Hog1 stress activated protein kinase was discovered about 20 years ago. Hog1 is the core of the intracellular signaling pathway that governs the adaptive response to osmotic stress in this species. The main endpoint of this program is synthesis and intracellular retention of glycerol, as a compatible osmolyte. Despite many details of the signaling pathways and yeast responses to osmotic challenges have already been described, genome-wide approaches are contributing to refine our knowledge of yeast adaptation to hypertonic media. In this work, we used a quantitative fitness analysis approach in order to deepen our understanding of the interplay between yeast cells and the osmotic environment. Genetic requirements for proper growth under osmotic stress showed both common and specific features when hypertonic conditions were induced by either glucose or sorbitol. Tolerance to high-glucose content requires mitochondrial function, while defective protein targeting to peroxisome, GID-complex function (involved in negative egulation of gluconeogenesis), or chromatin dynamics, result in poor survival to sorbitol induced osmotic stress. On the other side, the competitive disadvantage of yeast strains defective in the endomembrane system is relieved by hypertonic conditions. This finding points to the Golgi-endosome system as one of the main cell components negatively affected by hyperosmolarity. Most of the biological processes highlighted in this analysis had not been previously related to osmotic stress but are probably relevant in an ecological and evolutionary context., This work was supported by grant AGL2015-63629-R (MINECO/FEDER, UE) and the project P10_AGR6544 (Junta de Andalucía, Spain).