Cerevisiae Cell Wall Research Articles

Effects of three different strains of Bacillus-based probiotics and Saccharomyces cerevisiae-based prebiotic on performance, egg components and gene expression of laying hens during phase II of production

This study aimed to investigate the impacts of three strains of probiotics (Bacillus spp. (B.)) and one prebiotic based on Saccharomyces cerevisiae cell wall (SCCW) supplements on performance, egg quality and immune-related gene expression of laying hens. The experiment lasted 16 weeks (52–68 weeks), during which 450 Hisex white layers at 52 weeks were randomly allocated into five dietary regimens (five replications of 18 birds per floor pen): T1, basal diet; T2, basal + 0.5 g/kg B. subtilis (DSM17299); T3, basal + 0.5 g/kg B. subtilis (DSM 5750) and B. licheniformis (DSM 5749); T4, basal + 0.4 g/kg B. subtilis PB6; and T5, basal + 0.25 g/kg SCCW. The results showed that hen-day egg production (HDEP) improved in T4 and T5, egg mass (EM) improved in T3, T4 and T5, and feed conversion ratio (FCR) improved in T4 and T5 compared to T1 (p < .001). Relative wet and dry yolk weight were higher in hens received T2, T4 and T5 (p < .05) and T2, T3, T4 and T5 (p < .001), respectively, compared to T1. Moreover, T2, T4 and T5 had higher expression of GnRH-2 gene compared to T1 (p < .01). In conclusion, the dietary inclusion of SCCW-based prebiotic (T5) and Bacillus spp. probiotic strains, especially T4 B. subtilis PB6 improved production performance, egg components and GnRH-II gene expression of laying hens during phase II of the production cycle and hold a great promise for boosting productivity and supporting health status of layers raised on AGPs-free diets.

Study of the adjuvant properties of beta-glucans from &lt;i&gt;Saccharomyces Cerevisiae&lt;/i&gt; yeast

To increase the effectiveness and immunogenicity of modern vaccines, especially subunit ones, it is required to use adjuvants. Polysaccharides, due to their safety and biocompatibility, are desirable candidates for the creation of vaccine adjuvants. The aim of our study was to develop a method for obtaining beta-Glucans from the yeast Saccharomyces cerevisiae cell wall, and evaluate their adjuvant properties. The high purity and non-toxicity of the resulting preparation was achieved by using enzyme complexes of cellulase and protease in combination with ultrasound (22 kHz) at the purification stage. The developed scheme allows for the yield of beta-Glucans up to 2 g from 100 g of the biomass of wet cells. The adjuvant properties of beta-Glucans were studied in 50 male BALB/c mice, weighing 16–18 g. Immunization was performed twice, with a 14-day interval, intramuscularly, 200 μl per animal. The recombinant receptor-binding domain (RBD) of the surface S protein of the SARS-CoV-2 virus (Wuhan-Hu-1 and B.1.617.2 (Delta)) was used as an antigen, at a dose of 50 μg per animal. A positive control group was administered with the antigen combined with aluminum hydroxide. As a negative control, mice injected with the saline solution were used. The titers of specific antibodies in the blood sera were determined by ELISA assays. RBD (Wuhan-Hu-1 and Delta), and S protein (Wuhan-Hu-1, Delta and Omicron) were used as antigens. The titers of virus-neutralizing antibodies were measured in neutralization tests using SARS-CoV-2 virus strains Wuhan-Hu-1, Delta (B.1.617.2) and Omicron (B.1.1.529). The results of the study have shown that beta-Glucans have the ability to enhance the production of specific and virus-neutralizing antibodies in mice immunized with RBD. The titers of specific and virus neutralizing antibodies are comparable to their levels in the group immunized with RBD and Al(OH)₃. It has been found in the experiments in white outbred ICR mice that the preparation belongs to practically non-toxic substances. Therefore, it can be concluded that the use of beta-Glucans could become a preferable alternative to the conventional adjuvants based on aluminum salts, being biocompatible, biodegradable and non-toxic substances of low labor-intensive production.

The roles of Saccharomyces cerevisiae on the bioaccessibility of phenolic compounds.

Phenolic compounds are a group of non-essential dietary compounds that are widely recognized for their beneficial health effects, primarily due to their bioactive properties. These compounds which found in a variety of plant-based foods, including fruits, vegetables, and grains are known to possess antimicrobial, antioxidant, anti-inflammatory, and anti-carcinogenic properties. However, the health effects of these compounds depend on their bioaccessibility and bioavailability. In recent years, there has been growing interest in the use of probiotics for promoting human health. Saccharomyces cerevisiae is a yeast with potential probiotic properties and beneficial health effects. Biosorption of phenolic compounds on Saccharomyces cerevisiae cell walls improves their bioaccessibility. This characteristic has also allowed the use of this yeast as a biosorbent in the biosorption process due to its low cost, safety, and easy availability. S. cerevisiae enhances the bioaccessibility of phenolic compounds as a delivery system under in vitro digestion conditions. The reason for this phenomenon is the protective effects of yeast on various phenolic compounds under digestion conditions. This article shows the role of S. cerevisiae yeast on the bioaccessibility of various phenolic compounds and contributes to our understanding of the potential impact of yeasts in human health.

Dietary supplementation of prebiotic yeast Saccharomyces cerevisiae cell wall promotes growth performance and intestinal health in broiler chickens challenged with Clostridium perfringens

ABSTRACT 1. This study evaluated the effectiveness of yeast (S accharomyces cerevisiae) cell wall (YCW) supplementation on the growth performance, carcase characteristics, serum biomarkers, liver function, ileal histology and microbiota of broiler chickens challenged with Clostridium perfringens (C. perfringens). 2. In a 35-d trial, 240 chicks aged 1-d-old were randomly assigned to one of four treatment groups, each with 10 replicates: control (CON) with no challenge or additives, challenged with C. perfringens (CHAL), CHAL and supplemented with YCW at either 0.25 g/kg (YCW0.25) or 0.5 g/kg (YCW0.5). 3. In comparison to CON, the CHAL birds had reduced growth performance, survival rate, dressing percentage, breast meat yield, levels of total protein (TP), globulin (GLO), glucose (GLU), total antioxidant capacity (T-AOC) and total superoxide dismutase (T-SOD), as well as a decreased Lactobacillus population (P < 0.01). Additionally, this group showed elevated levels of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), and C. perfringens count (P < 0.01). Compared to CHAL, the YCW0.25 or YCW0.5 groups had improved growth performance, survival rate, dressing percentage, breast meat yield, levels of TP, GLO, GLU, and T-AOC, as well as the activities of T-SOD, GOT, and GPT, villus height, villus surface area, villus height to crypt depth ratio, and the populations of both Lactobacillus and C. perfringens; (P < 0.01). 4. The data suggested that YCW supplementation at either 0.25 or 0.50 g/kg can restore the growth performance of broiler chickens during a C. perfringens challenge.

Effect of a Bacillus subtilis plus Yeast Cell Wall Synbiotic on Salmonella Enteritidis Colonization in Ceca of Layer Pullets

Salmonella Enteritidis (SE) is a major contamination concern in eggs and risk for Salmonellosis in humans. Strains of Bacillus subtilis and yeast cell wall can be used as substitutes for antibiotic substances in feed against Salmonella in poultry. The objective of this study was to assess the effect of BacPack® (Quality Technology International, Inc., Elgin, IL, USA) Q1+1 (BPQ11), a feed additive combination of a Bacillus subtilis strain and Saccharomyces cerevisiae cell wall, on SE cecal colonization in Lohmann LSL pullets. A control group (CON) and a test group (BPQ) were each randomly assigned 100-day-old chicks. CON was fed a corn–soybean meal-based vegetarian mash diet, and BPQ was fed the control diet supplemented with BPQ11 for the duration of the study. At 8 days of age, chicks were orally challenged with a nalidixic acid-resistant SE strain at a dose of 6.3 × 107 colony forming units (CFUs) per bird. At 7, 11, 15, and 19 days post-challenge (DPC), 25 birds per group were euthanized, and their cecal contents were collected and analyzed for SE. SE counts were 6.88, 7.98, 7.79, and 7.50 in CON and 7.18, 7.31, 6.35, and 6.30 log10 CFU/g in BPQ at 7, 11, 15, and 19 DPC, respectively. SE did not differ between CON and BPQ at 7 DPC; however, BPQ had lower (p &lt; 0.0001) SE at 11 (−0.67), 15 (−1.45), and 19 (−1.20 log10 CFU/g) DPC. Results indicate that synbiotic BPQ11 may be a useful dietary pre-harvest tool for SE management in layer birds.

Dectin-1 ligands produce distinct training phenotypes in human monocytes through differential activation of signaling networks

Cells of the innate immune system retain memory of prior exposures through a process known as innate immune training. β-glucan, a Dectin-1 ligand purified from the Candida albicans cell wall, has been one of the most widely utilized ligands for inducing innate immune training. However, many Dectin-1 ligands exist, and it is not known whether these all produce the same phenotype. Using a well-established in vitro model of innate immune training, we compared two commercially available Dectin-1 agonists, zymosan and depleted zymosan, with the gold standard β-glucan in the literature. We found that depleted zymosan, a β-glucan purified from Saccharomyces cerevisiae cell wall through alkali treatment, produced near identical effects as C. albicans β-glucan. However, untreated zymosan produced a distinct training effect from β-glucans at both the transcript and cytokine level. Training with zymosan diminished, rather than potentiated, induction of cytokines such as TNF and IL-6. Zymosan activated NFκB and AP-1 transcription factors more strongly than β-glucans. The addition of the toll-like receptor (TLR) ligand Pam3CSK4 was sufficient to convert the training effect of β-glucans to a phenotype resembling zymosan. We conclude that differential activation of TLR signaling pathways determines the phenotype of innate immune training induced by Dectin-1 ligands.

Covalent immobilization of Saccharomyces cerevisiae and Candida albicans cell walls for aflatoxin M1 bio‐detoxification

AbstractThe study compared the bio‐detoxification capabilities of Saccharomyces cerevisiae and Candida albicans cell walls for aflatoxin M1 (AFM1). The yeast cell walls were disrupted using thermal shock‐ultrasound, resulting in 75 nm particles, as confirmed by dynamic light scattering. These disrupted cell walls were then immobilized on nano‐zeolite and entrapped in ca‐alginate. SEM, FTIR &amp; XRD confirmed their physical absorption on the nano‐zeolite and entrapment in ca‐alginate. Samples were exposed to AFM1 for 15 min and 24 h, either in combination or free, before or after immobilization. HPLC analysis revealed significant variations in AFM1 reduction. The highest reduction of 89.49% was observed after 15 min with alginate treatment, while the immobilized‐entrapped C. albicans cell wall showed the lowest reduction of 24.77% after 24 h. Both free Candida cell walls and immobilized‐entrapped Saccharomyces cell walls showed impressive detoxification abilities. Additionally, immobilized‐entrapped cell walls are reusable and a sustainable choice for industrial use.

Defense-related gene expression in response to the application of biological control agents in banana

Black Sigatoka, caused by P. fijiensis, is the most important banana disease in Latin America as increasing applications of chemical fungicides used for its management result in both higher banana production costs and pathogen resistance. Spores of Bacillus subtilis, a proprietary Trichoderma sp., and a biological fermentation product composed of Saccharomyces cerevisiae cell walls and copper sulfate, were applied separately to evaluate potential defense responses in banana plants. The leaves were artificially inoculated with the pathogen, and the biological control agents were applied to the soil to avoid direct antagonism with the pathogen. Significantly lower (P < 0.05) area under disease progress curve values were observed among all treated plants compared with the control, with the lowest value measured in the treatment with a 5 % (w/v) concentration of a yeast cell wall product. In a second trial, the same biological control agents were applied to banana plants at 5 % (w/v) concentration to determine the relative expression of defense-related genes. Higher relative expression (P < 0.05) of PR3 and PR9 was observed at 3 and 24 h after application in the plants treated with B. subtilis and Trichoderma sp., respectively. In the plants treated with the yeast cell wall product, higher relative expression (P < 0.05) of PR3 was measured 48 h after application. The findings indicate that plant defenses may be activated by the biological control agents.

Hidden attributes of zymosan in the pathogenesis of inflammatory diseases: A tale of the fungal agent.

Inflammation triggers immune system-mediated actions that contribute to the development of multiple diseases. Zymosan, a polysaccharide derived from the Saccharomyces cerevisiae cell wall, is mainly made up of glucan and mannan residues and is used as an inflammatory agent. Zymosan is a fungal product that activates the immune system through the activation of inflammatory signaling pathways, and releases a variety of harmful chemicals including pattern recognition receptors, reactive oxygen species (ROS), and the excitatory amino acid glutamate, cytokines, adhesion molecules, etc. Furthermore, we will dive into the molecular mechanistic insights through which this fungal agent induces and influences various inflammatory diseases such as cardiovascular, neuroinflammation, diabetes, arthritis, and sepsis. Based on the evidence, zymosan appears to be a promising inflammatory-inducing agent. Nonetheless, more animal data is the need of the hour to catch a glimpse and unravel the capacity of zymosan.

Effect of Adding an Organic Binder on Health of Cows Fed with Mycotoxins Contaminated Diet

Mycotoxins contamination occurring in dairy cow's diet is responsible for devastating effects on livestock health. Among different strategies, using organic adsorbents is a promising approach to reduce the toxicity of mycotoxins. This study investigated the effects of an organic adsorbent containing Lactobacillus brevis TD4, Lactobacillus paracasei TD3, and Saccharomyces cerevisiae cell wall on milk production, somatic cell count, blood parameters (white blood cell [WBC], lymphocyte [LYM], neutrophil, basophil, monocyte, eosinophil, red blood cell, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin) and liver function (alanine transaminase [ALT], gamma-glutamyl transferase [GGT], aspartate transaminase [AST], alkaline phosphatase [ALP], urea, total protein, albumin) in dairy cows fed a naturally contaminated diet with Zearalenone and Deoxynivalenol. The amounts of mycotoxins Zearalenone (ZEA) and Deoxynivalenol (DON) in feed ingredients were measured using the HPLC method. Ten Holstein dairy cows received organic adsorbents daily in their diets for four weeks. Milk and blood samples were taken from cows before the start of feeding adsorbent (CTRL), during the feeding period (FP), and one week after removal of adsorbent from the diet (RP). Totally, the amount of measured ZEA and DON toxins in the diet were 389 and 1254.6 ppb, respectively. Feeding of organic adsorbent significantly increased milk production, total serum protein, and albumin compared to CTRL (P&lt;0.01). Also, numerically lower somatic cell count in their milk and a significant decrease (P&lt;0.01) in serum urea were resulted. Among examined blood parameters, the number of WBC and LYM significantly decreased (P&lt;0.01) after feeding with the organic binder in comparison to the control period. Furthermore, except for a significant increase in the level of AST (P&lt;0.05), the other liver function examined parameters were not affected. The consumption of feed containing low-cost organic adsorbent including Lactobacillus bacteria and yeast cell wall can improve the physical condition and health of dairy cows and reduce economic losses in livestock production.

The effect of deletions of genes encoding Pho3p and Bgl2p on the polyphosphate level, stress adaptation and attachment of these proteins in &lt;i&gt;Saccharomyces cerevisiae&lt;/i&gt; cell wall

Inorganic polyphosphates (polyP), according to literature data, are involved in the regulatory processes of molecular complex of the Saccharomyces cerevisiae cell wall (CW). The aim of the work was to reveal relationship between polyP, acid phosphatase Pho3p, and the major CW protein, glucanosyl transglycosylase Bgl2p, which is the main glucan-remodelling enzyme with amyloid properties. It has been shown that the yeast cells with deletion of the PHO3 gene contain more high molecular alkali-soluble polyP and are also more resistant to exposure to alkali and manganese ions compared to the wild type strain. This suggests that Pho3p is responsible for hydrolysis of the high molecular polyP on the surface of yeast cells, and these polyP belong to the stress resistance factors. The S. cerevisiae strain with deletion of the BGL2 gene is similar to the Δpho3 strain both in the level of high molecular alkali-soluble polyP and in the increased resistance to alkali and manganese. Comparative analysis of the CW proteins demonstrated correlation between the extractability of the acid phosphatase and Bgl2p, and also revealed a change in the mode of Bgl2p attachment to the CW of the strain lacking Pho3p. It has been suggested that Bgl2p and Pho3p are able to form a metabolon or its parts that connects biogenesis of the main structural polymer of the CW, glucan, and catabolism of an important regulatory polymer, polyphosphates.

Whole β-glucan particle attenuates AOM/DSS-induced colorectal tumorigenesis in mice via inhibition of intestinal inflammation.

Yeast β-glucan is a polysaccharide purified from the Saccharomyces cerevisiae cell wall, and its multiple biological activities are essential for immune regulation. However, the effect of β-glucan on the intestinal immune response during colitis-associated colorectal cancer (CAC) is unclear. Here, we explore the possible role of β-glucan in the development of CAC. Wild type (WT) mice with CAC induced by azoxmethane (AOM) and dextran sodium sulfate (DSS) had fewer tumors than untreated mice after oral β-glucan because of increased antitumor dendritic cells (DCs) in the tumor microenvironment, resulting in more CD8+ T cells and the production of related cytokines. β-glucan also increased resistance to DSS-induced chronic colitis by reshaping the inflammatory microenvironment. These data suggest that β-glucan improves experimental intestinal inflammation and delays the development of CAC. Therefore, β-glucan is feasible for treating chronic colitis and CAC in clinical practice.

Effect of Deletions of the Genes Encoding Pho3p and Bgl2p on Polyphosphate Level, Stress Adaptation, and Attachments of These Proteins to Saccharomyces cerevisiae Cell Wall.

Inorganic polyphosphates (polyP), according to literature data, are involved in the regulatory processes of molecular complex of the Saccharomyces cerevisiae cell wall (CW). The aim of the work was to reveal relationship between polyP, acid phosphatase Pho3p, and the major CW protein, glucanosyltransglycosylase Bgl2p, which is the main glucan-remodelling enzyme with amyloid properties. It has been shown that the yeast cells with deletion of the PHO3 gene contain more high molecular alkali-soluble polyP and are also more resistant to exposure to alkali and manganese ions compared to the wild type strain. This suggests that Pho3p is responsible for hydrolysis of the high molecular polyP on the surface of yeast cells, and these polyP belong to the stress resistance factors. The S. cerevisiae strain with deletion of the BGL2 gene is similar to the Δpho3 strain both in the level of high molecular alkali-soluble polyP and in the increased resistance to alkali and manganese. Comparative analysis of the CW proteins demonstrated correlation between the extractability of the acid phosphatase and Bgl2p, and also revealed a change in the mode of Bgl2p attachment to the CW of the strain lacking Pho3p. It has been suggested that Bgl2p and Pho3p are able to form a metabolon or its parts that connects biogenesis of the main structural polymer of the CW, glucan, and catabolism of an important regulatory polymer, polyphosphates.

Pharmacological effect of T-NilPlus® and Synertox®, commercial anti-mycotoxins, on broiler chickens in Egypt

The present study was carried out to investigate the potential ameliorative effect of two commercial anti-mycotoxins, containing Saccharomyces cerevisiae cell wall as prebiotic (T-Nil Plus®) and Bacillus subtilis as probiotic (Synertox®) on performance and some biochemical parameters of broilers. One hundred and twenty chicks one day old chicks were divided into 3 equal groups. 1st group was served as control, 2nd group was given T-Nil Plus®. The 3rd group was given Synertox®. Chicken’s performance was estimated. Serum samples obtained from each group for biochemical analysis. Tissues samples were collected for histopathological examination. The obtained results revealed that, T-Nil plus® induced a marked reduction in body weight gain and an elevation in Feed consumption, moreover, a marked elevation in, alanine aminotransferase (ALT), creatinine and malondialdehyde (MDA) and a marked reduction in aspartate aminotransferase (AST) was detected. While Synertox® caused a significant decrease in body weight, body weight gain and no change in feed conversion rate (FCR) and a marked elevation in ALT, creatinine and a marked reduction in AST and nitric oxide (NO) and it caused a significant reduction in serum glucose level of the birds. In conclusion, Synertox® induced a powerful effect comparing to T-Nil Plus®, as it induces a good FCR and increases the response of the birds against oxidative stress.

Novel albendazole-glucan particles for enhancing intestinal absorption and improving hepatic targeting.

Glucan particles (GPs) are derived from the Saccharomyces cerevisiae cell wall. The hollow particles composed of β-1,3-D-glucan have been extensively studied in terms of immune regulation and macrophage-targeted drug delivery. Albendazole (ABZ) is a benzimidazole drug with good anti-parasitic activity and is the drug recommended by the World Health Organization for the first-line treatment of hydatid disease. A dynamic light scatterometer, scanning electron microscope, and transmission electron microscope were used to characterize the ABZ-GPs. High-performance liquid chromatography (HPLC), laser scanning confocal microscope (LSCM) and an in vivo small animal imaging system were used to evaluate theability of ABZ-GPs to be recognized by macrophages, whether ABZ-GPs are more readily absorbed and eliminated in the blood than the original ABZ drug in rats, and the ability of ABZ-GPs to target the mouse liver. The ABZ-GPs were successfully constructed to achieve fluorescence, magnetic resonance imagining, and laser confocal microscopy imaging. The glucan shell effectively protects ABZ from enzymatic degradation and from being pumped out in the gastrointestinal tract. The analysis of ABZ and its major metabolite albendazole sulfoxide in the rat plasma and mouse liver showed that compared to the ABZ suspension group, the degradation of ABZ-GPSs in the blood was low, and the targeting of ABZ-GPSs in the liver was significantly enhanced. In the oral treatment of hepatic hydatid disease, GPs can be used as carriers to achieve the targeted transport of ABZ, which in turn can be used for the targeted therapy of liver echinococcosis. Thus, ABZ-GPs may be a promising form of targeted therapy.

The synbiotic mixture of Bacillus licheniformis and Saccharomyces cerevisiae extract aggravates dextran sulfate sodium induced colitis in rats

BackgroundUncertain effects of probiotics and/or prebiotics have been reported in experimental and clinical colitis. This study aims to examine the effects of a synbiotic combination comprising Bacillus licheniformis DSM 17236 and Saccharomyces cerevisiae cell wall extract on dextran sulfate sodium (DSS)-induced colitis in Sprague Dawley rats.MethodsAcute colitis was induced in rats by oral administration of DSS 3.5% for 7 days. Fifty rats were divided equally into five groups; one control group and the other groups were induced with colitis and treated with or without the tested synbiotic, mixed with diet, for 28 days and sulfasalazine (100 mg/kg) via intragastric tube once daily for 14 days.ResultsSymptomatically, the synbiotic administration raised the disease activity index (DAI) to comparable scores of the DSS group, specially from the 2nd to 7th days post DSS intoxication. It also induced a significant (p < 0.05) amplification of WBCs, myeloperoxidase (MPO), malondialdehyde (MDA), nuclear factor kappa B (NF-kB) expression and proinflammatory cytokines tumor necrosis factor alpha (TNFα), interferon gamma (INFγ), and interleukin-1 beta (IL-1β) while depressed the antioxidant enzymes glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD) when compared with the DSS and control groups. The DSS intoxicated and Synbiotic+DSS groups showed desquamations of the covering epithelium, noticeable diffuse leukocytic infiltrations, sever catarrhal enteritis, ischemic colitis with diffuse coagulative necrosis of the entire colonic mucosa. Contrarily, sulfasalazine proved to be effective in the reduction of the tested inflammatory markers and the pathological degenerative changes of the DSS ulcerative colitis.ConclusionThe examined synbiotic did not ameliorate but aggravated the DSS-induced colitis, so it should be subjected to intensive experimental and clinical testing before their use in animals and human.

Limosilactobacillus fermentum Strain 3872: Antibacterial and Immunoregulatory Properties and Synergy with Prebiotics against Socially Significant Antibiotic-Resistant Infections of Animals and Humans.

Limosilactobacillus fermentum strain 3872 (LF3872) was originally isolated from the breast milk of a healthy woman during lactation and the breastfeeding of a child. The high-quality genome sequencing of LF3872 was performed, and a gene encoding a unique bacteriocin was discovered. It was established that the bacteriocin produced by LF3872 (BLF3872) belongs to the family of cell-wall-degrading proteins that cause cell lysis. The antibacterial properties of LF3872 were studied using test cultures of antibiotic-resistant Gram-positive and Gram-negative pathogens. Gram-positive pathogens (Staphylococcus aureus strain 8325-4 and S. aureus strain IIE CI-SA 1246) were highly sensitive to the bacteriolytic action of LF3872. Gram-negative pathogens (Escherichia coli, Salmonella strains, and Campylobacter jejuni strains) were more resistant to the bacteriolytic action of LF3872 compared to Gram-positive pathogens. LF3872 is a strong co-aggregator of Gram-negative pathogens. The cell-free culture supernatant of LF3872 (CSLF3872) induced cell damage in the Gram-positive and Gram-negative test cultures and ATP leakage. In the in vitro experiments, it was found that LF3872 and Actigen prebiotic (Alltech Inc., Nicholasville, KY, USA) exhibited synergistic anti-adhesive activity against Gram-negative pathogens. LF3872 has immunoregulatory properties: it inhibited the lipopolysaccharide-induced production of proinflammatory cytokines IL-8, IL-1β, and TNF-α in a monolayer of Caco-2 cells; inhibited the production of IL-12 and stimulated the production of IL-10 in immature human dendritic cells; and stimulated the production of TGF-β, IFN-γ, and IgA in the immunocompetent cells of intestinal Peyer’s patches (PPs) in mice. These results indicate the possibility of creating a synbiotic based on LF3872 and a prebiotic derived from Saccharomyces cerevisiae cell wall components. Such innovative drugs and biologically active additives are necessary for the implementation of a strategy to reduce the spread of antibiotic-resistant strains of socially significant animal and human infections.

Non-classical monocytes contribute to innate immune training in cattle.

Innate immune training is defined as a property of innate immune cells to react stronger to a secondary contact with pathogens. Induction of innate immune training has been reported for a variety of pathogens and selected pattern recognition receptor-ligands, such as β-glucans (βG). We examined whether Saccharomyces cerevisiae cell wall component βG induces training in bovine monocytes in vitro based on a heightened TNF secretion after stimulation by trained monocyte-derived macrophages with Escherichia coli LPS. Sorted CD14-expressing monocytes (classical and intermediate monocytes), as well as single populations of sorted classical, intermediate and non-classical monocytes could not be trained by βG, whereas macrophages derived from plastic-adherent mononuclear cell preparations displayed features of a trained function. The hypothesis, that non-classical monocytes need to be present in a mixed monocyte population in order to be trained by βG could be verified by a successful training of positively sorted whole monocyte populations (CD14CD16/M) containing all three monocyte subpopulations. The trainability depended on conditions favoring M1 polarization of macrophages. Altogether, innate immune training of bovine monocytes seems to depend on the presence of non-classical monocytes. This adds new information to the role of this monocyte subpopulation in the bovine immune system.

Dissection and enhancement of prebiotic properties of yeast cell wall oligosaccharides through metabolic engineering

Saccharomyces boulardii is a yeast clinically used for treating various symptoms of gastrointestinal dysbiosis. Despite their genomic relatedness, S. boulardii has a distinctive cell wall oligosaccharide composition compared to baker's yeast S. cerevisiae, such as higher mannan content. Here we explore the beneficial effects of S. boulardii cell wall oligosaccharides through metabolic engineering. We increased the production of guanosine diphosphate (GDP)-mannose, the substrate for cell wall mannan biosynthesis, by perturbing glycolysis flux and overexpressing the enzymes in the GDP-mannose biosynthesis pathway. Combined with overexpression of a cell wall mannoprotein and dolichol phosphate mannose synthase, the cell wall mannan content of S. boulardii increased up to 52%. The identical engineering resulted in marginal changes in the S. cerevisiae cell wall. S. boulardii showed a higher adhesive capacity against Salmonella enterica Typhimurium than S. cerevisiae, and yeast-bacteria sedimentation rates were positively correlated with cell wall mannan contents. Besides, S. boulardii biomass selectively proliferated Bacteroides thetaiotaomicron over Clostridioides difficile more efficiently than S. cerevisiae, and the selectivity was further enhanced by amplifying the cell wall mannan. Collectively, we report the important prebiotic roles of cell wall oligosaccharides in the protective functions of S. boulardii and present a unique metabolic engineering approach to modulate the functions.

Effect of a Mycotoxin Binder (MMDA) on the Growth Performance, Blood and Carcass Characteristics of Broilers Fed Ochratoxin A and T-2 Mycotoxin Contaminated Diets.

Simple SummaryThe contamination of feed with mycotoxins is a global concern, resulting in adverse effects on productivity and animal health and, therefore, a great economic loss. Ochratoxin A and T-2 mycotoxins are among the mycotoxins that contaminate animal feed. These mycotoxins could adversely affect the health of broilers, and the most effective method to mitigate the toxic effects of mycotoxins is the use of detoxifying agents. In the present experiment, broiler chickens were allotted into five groups. Group 1 received a non-contaminated diet; group 2 received a non-contaminated diet + 3 g/kg of a mycotoxin binder (MMDA); group 3 received a non-contaminated diet + 0.5 mg/kg OTA + 1 mg/kg T-2 toxin; group 4 received a non-contaminated diet + 0.5 mg/kg OTA + 1 mg/kg T-2 toxin + 1 g/kg MMDA; and group 5 received a non-contaminated diet + 0.5 mg/kg OTA + 1 mg/kg T-2 toxin + 3 g/kg MMDA for 35 days. The results revealed that OTA and T-2 toxin negatively affected the productive parameters and some blood and carcass characteristics of broiler chickens. The addition of the detoxifying agent (MMDA at 1 or 3 g/kg feed) to contaminated diets alleviated the adverse effects observed on productivity and the broilers heath related parameters. The present study was conducted to evaluate the efficacy of the feed additive, a novel multicomponent mycotoxin detoxifying agent (MMDA) containing modified zeolite (clinoptilolite), Bacillus subtilis, B. licheniformis, Saccharomyces cerevisiae cell walls, and silymarin, as detoxifiers of 0.5 mg/kg (0.5 ppm) ochratoxin A (OTA) and 1 mg/kg (1 ppm) T-2 toxin on broiler chickens. A total of 240 1-old broiler chickens (Ross 308) were randomly distributed into five different dietary treatments: (1) control (non-contaminated diet); (2) non contaminated diet + 3 g/kg of MMDA; (3) non-contaminated diet + 0.5 mg/kg OTA + 1 mg/kg T-2 toxin; (4) non-contaminated diet + 0.5 mg/kg OTA + 1 mg/kg T-2 toxin + 1 g/kg MMDA; and (5) non-contaminated diet + 0.5 mg/kg OTA + 1 g/kg T-2 toxin + 3 g/kg MMDA. The results showed that, in the starter period, from 1 to 10 days, the presence of OTA and T-2 mycotoxins reduced the consumption of feed and the growth of the broilers, and no effects of the detoxifying product were observed in the productivity of the chickens, at any of the doses tested, compared to the contaminated control (treatment 3). However, in the growing period, the same negative effect of mycotoxins was registered, but a recovery was observed in the consumption of feed and in the weight of the broilers that consumed 3 g/kg of the MMDA mycotoxin binder, reaching similar values to those of chickens fed uncontaminated control diets. The presence of mycotoxins in feed led to a reduction in the concentration of total proteins and albumin in blood compared to controls, and the presence of the detoxifying product partially reversed this effect. The breast yield of the chickens fed with mycotoxins was lower than that of the animals fed with the control feed and was not affected by the presence of the product tested, at 1 or 3 g/kg. The weight of the different organs (liver, gizzard, kidneys, or spleen), the intestinal pH, the histology of the small intestine, and oral lesions were not affected by the experimental treatments. In summary, the productive parameters and some blood and carcass characteristics of broiler chickens were impaired by the dietary presence of OTA and T-2 toxin. The tested product included at 1 or 3 g/kg feed in contaminated diets improved performance and seems to be effective in partly counteracting the deleterious effects of the tested mycotoxins.