Unique Probiotic Properties and Bioactive Metabolites of Saccharomyces boulardii

Systematic Engineering for Efficient Uric Acid-Degrading Activity in Probiotic Yeast Saccharomyces boulardii

Hyperuricemia, caused by uric acid disequilibrium, is a prevalent metabolic disease that most commonly manifests as gout and is closely associated with a spectrum of other comorbidities such as renal disorders and cardiovascular diseases. While natural and engineered probiotics that promote catabolism of uric acid in the intestine have shown promise in relieving hyperuricemia, limitations in strain efficiency and the requirements for achieving high performance remain major hurdles in the practical application of probiotic-mediated prevention and management. Here, we employed a systematic strategy to engineer a high-efficiency uric acid catabolism pathway in S. cerevisiae. An uricase from Vibrio vulnificus, exhibiting high-level activity in S. cerevisiae, was identified as the uric acid-degrading component. The expression level and stability of urate transporter UapA were improved by constructing a chimera, enabling reliable uric acid import in S. cerevisiae. Additionally, constitutive promoters were selected and combinatorially assembled with the two functional components, creating a collection of pathways that confer varied levels of uric acid catabolic activity to S. cerevisiae. The best-performing pathway can express uric acid-degrading activity up to 365.32 ± 20.54 μmol/h/OD, requiring only simple cultivation steps. Eventually, we took advantage of the genetic similarity between model organism S. cerevisiae and probiotic S. boulardii and integrated the optimized pathway into identified high-expression integration loci in the S. boulardii genome. The activity can be stably maintained under high-density fermentation conditions. Overall, this study provided a high-potential hyperuricemia-managing yeast probiotic strain, demonstrating the capabilities of developing recombinant probiotics.

Clinical efficacy of probiotic supplementation in the treatment of knee osteoarthritis: a meta-analysis

Background

We aimed to systematically evaluate and analyze the clinical efficacy of oral probiotics in the treatment of knee osteoarthritis (KOA) based on the theory of "gut-joint axis."

Methods

We searched PubMed, The Cochrane Library, Embase, China Knowledge Network (CNKI), Wanfang Database, and Wipro Database (CQVIP) databases for clinical randomized controlled trials of oral probiotics for the treatment of KOA. The literature was organized by Note express software, and the quality of the included literature was evaluated according to the Cochrane systematic evaluation method, and meta-analysis was performed using RevMan 5.4 software.

Results

Five randomized controlled trials with 694 participants were included in this study, and the results of the meta-analysis showed that the observation group experienced significant reductions in the Western Ontario and McMaster Universities Osteoarthritis Index total score, visual analog score, and high-sensitivity C-reactive protein level compared to the control group, but did not show significant differences in improvement of stiffness and regulation of body weight.

Conclusion

Oral probiotics had an ameliorative effect on function, pain, and inflammatory response in patients with KOA, but our results need to be validated in future large-scale studies.

Systematic review registration

The website is https://www.crd.york.ac.uk/PROSPERO/.

Genomic, Probiotic, and Functional Properties of Bacteroides dorei RX2020 Isolated from Gut Microbiota

BACKGROUND/OBJECTIVES

Gut microbiota is essential for maintaining host immune homeostasis and has been confirmed to be closely related to some intestinal and extraintestinal diseases. Bacteroides, as the dominant bacterial genus in the human gut, has attracted great attention due to its excellent metabolic activity, but there are few studies on Bacteroides dorei species. In our previous study, a gut commensal strain, Bacteroides dorei RX2020 (B. dorei), was isolated from healthy human feces and exhibited superior flavonoid metabolic activity, prompting further analysis of its uncharacterized genomic features, probiotic potential, safety, and immunomodulatory activity.

RESULTS

The results showed that B. dorei exhibited intrinsic probiotic functionalities with preserved genomic and phenotypic stability, demonstrated safety profiles in murine models through in vivo assessments, and conferred antagonistic activity against enteric foodborne pathogens via competitive exclusion. The strain also demonstrated abundant metabolic activity and was involved in the metabolism of tryptophan and bile acids (BAs). Moreover, B. dorei can promote the production of IFNβ by dendritic cells (DCs) to inhibit the replication of influenza virus in epithelial cells, which may be achieved by regulating host metabolism.

CONCLUSIONS

This study reveals the potential of B. dorei as next-generation probiotics (NGPs), contributing to a broader understanding and application of these novel probiotics in health and disease management.

Effects of Long-Term Heavy Metal Exposure on the Species Diversity, Functional Diversity, and Network Structure of Oral Mycobiome

Oral fungal homeostasis is closely related to the state of human health, and its composition is influenced by various factors. At present, the effects of long-term soil heavy metal exposure on the oral fungi of local populations have not been adequately studied. In this study, we used inductively coupled plasma-mass spectrometry (ICP-MS) to detect heavy metals in agricultural soils from two areas in Gansu Province, northwestern China. ITS amplicon sequencing was used to analyze the community composition of oral buccal mucosa fungi from local village residents. Simultaneously, the functional annotation of fungi was performed using FUNGuild, and co-occurrence networks were constructed to analyze the interactions of different functional fungi. The results showed that the species diversity of the oral fungi of local populations in the soil heavy metal exposure group was lower than that of the control population. The relative abundance of Apiotrichum and Cutaneotrichosporon was higher in the exposure group than in the control group. In addition, Cutaneotrichosporon is an Animal Pathogen, which may lead to an increased probability of disease in the exposure group. Meanwhile, there were significant differences in the co-occurrence network structure between the two groups. The control group had a larger and more stable network than the exposure group. Eight keystone taxa were observed in the network of the control group, while none were observed in that of the exposure group. In conclusion, heavy metal exposure may increase the risk of diseases associated with Apiotrichum and Cutaneotrichosporon infection in the local populations. It can also lead to the loss of keystone taxa and the reduced stability of the oral fungal network. The above results illustrated that heavy metal exposure impairs oral fungal interactions in the population. This study extends our understanding of the biodiversity of oral fungi in the population and provides new insights for further studies on the factors influencing oral fungal homeostasis.

Identification of potential key metabolites in synbiotic yoghurt made with probiotic Saccharomyces cerevisiae var. boulardii CNCM I-745 and prebiotic inulin by non-targeted metabolomics analysis

Probiotic yeasts are attracting widespread attention due to their unique therapeutic properties and benefits to human health, but how they function in food system has been much less studied. Here, yoghurt was prepared using probiotic Saccharomyces cerevisiae var. boulardii CNCM I-745 with and without addition of prebiotic inulin, and the metabolic changes in yoghurt during 28 days of storage at 4 °C were analyzed by non-targeted metabolomics method. Potential functional metabolites that were differentially expressed in the synbiotic yoghurt added with inulin were identified, including hydroxyisocaproic acid, indolelactic acid, α-lactose, pelargonic acid, trehalose, 2-isopropylmalic acid, maltitol, D-glucuronic acid, raffinose, uric acid, and maltohexaose. These differential metabolites might play an important role in improving probiotic yeast survival and synbiotic yoghurt functionality through relevant metabolic pathways. This study promotes comprehension on the metabolic properties of the probiotic yeast in yoghurt with significance in exploring its applications in synbiotic dairy products.

Multifunctional Lactiplantibacillus plantarum SQ1 from Baijiu Daqu: Application of histamine degradation and probiotic potential in yogurt production

Yogurt in this study is a milk drink with probiotics added during the fermentation process and has a variety of ingredients. To identify microorganisms capable of efficiently degrading histamine, thereby enhancing yogurt's quality and safety. This study focused on screening Lactiplantibacillus plantarum (L. plantarum) from Baijiu Daqu (saccharification starter for Baijiu brewing), which exhibits histamine-reducing properties through biological characterization and molecular biology techniques. The results indicated that the strain has an optimal growth temperature of 37 °C, can survive within a pH range of 3 to 9, and demonstrates tolerance levels for sugar (4 % to 12 %) and salt (1 % to 7 %). Additionally, it possesses notable surface hydrophobicity and self-aggregation capabilities, along with robust survival rates in gastrointestinal fluids and bile salts. This strain also produces more than 40 flavor compounds, including trimethylpyrazine, pyrrole, and phenylglyoxal; its metabolites inhibit certain pathogenic bacteria, such as Escherichia coli (E. coli) and Pseudomonas putida (P. putida). Following co-fermentation with this bacterium in yogurt, there was a significant reduction in histamine levels-achieving a degradation rate of (41.74 ± 1.86)%. In the study, genes related to histamine degradation, such as the multicopper oxidase gene (cueO, EC: 1.16.3.4) and glyceraldehyde-3-phosphate dehydrogenase (gapA, EC: 1.2.1.12), were found to be present L. plantarum SQ1 by whole genome sequencing. This research provides technical support for reducing histamine concentrations in the manufacturing process of high-histamine fermented foods such as yogurt or aged vinegar, thereby reducing the risk of adverse reactions to consumers and laying the theoretical foundation for safer and healthier dairy production.

Engineering Saccharomyces cerevisiae for medical applications

BACKGROUND

During the last decades, the advancements in synthetic biology opened the doors for a profusion of cost-effective, fast, and ecologically friendly medical applications priorly unimaginable. Following the trend, the genetic engineering of the baker's yeast, Saccharomyces cerevisiae, propelled its status from an instrumental ally in the food industry to a therapy and prophylaxis aid.

MAIN TEXT

In this review, we scrutinize the main applications of engineered S. cerevisiae in the medical field focusing on its use as a cell factory for pharmaceuticals and vaccines, a biosensor for diagnostic and biomimetic assays, and as a live biotherapeutic product for the smart in situ treatment of intestinal ailments. An extensive view of these fields' academic and commercial developments as well as main hindrances is presented.

CONCLUSION

Although the field still faces challenges, the development of yeast-based medical applications is often considered a success story. The rapid advances in synthetic biology strongly support the case for a future where engineered yeasts play an important role in medicine.

Antioxidant and Antimicrobial Properties of Probiotics: Insights from In Vitro Assays

Probiotics are microorganisms that provide health benefits at adequate doses and exhibit notable antioxidant and antimicrobial activities. These properties play crucial roles in combating chronic diseases linked to oxidative stress and antimicrobial resistance. This review aimed to summarize the antioxidant and antimicrobial properties of probiotics determined in in vitro studies and discuss mechanistic actions and analysis methods. The MEDLINE (PubMed), Web of Science, Scopus, Science Direct, and Embase databases were utilized. The included articles demonstrated the antioxidant and antimicrobial activities of both isolated and food matrix-associated probiotics, with the most common genera being Lactobacillus, Bifidobacterium, Saccharomyces, and Streptococcus. Antioxidant activity was the most studied property, yielding varied results attributed to evaluation tests and probiotic strain. Antibacterial activity was consistently reported in all studies. Additionally, fermentation with probiotic microorganisms improved the content and bioaccessibility of bioactive compounds. In conclusion, analysis results highlight the antioxidant and antimicrobial activity of probiotics reported in in vitro studies. They enhance bioactive content and bioaccessibility and produce novel beneficial metabolites during fermentation. These results reinforce the therapeutic promise of probiotics associated with plant matrices and indicate the need for clinical studies to confirm their efficacy in improving human health.

Probiotic Potential of Yeasts Isolated from Fermented Beverages: Assessment of Antagonistic Strategies Against Salmonella enterica Serovar Enteritidis

Global concern about pathogenic resistance to antibiotics is prompting interest in probiotics as a strategy to prevent or inhibit infections. Fermented beverages are promising sources of probiotic yeasts. This study aimed to evaluate the antagonistic effects of Kluyveromyces marxianus, Wickerhamomyces anomalus, and Pichia manshurica strains from kefir and wine against Salmonella enterica serovar Enteritidis in intestinal epithelial cells. The ability of these yeasts to adhere to Caco-2/TC-7 cells was evaluated, as well as their influence on the ability of Salmonella to associate and invade these cells. The behavior of the pathogen was analyzed by (a) incubation of enterocytes with yeast before adding Salmonella, (b) co-incubation of Salmonella with yeast before contact with the enterocytes, and (c) incubation of Salmonella with yeast metabolites before contact with enterocytes. All yeast strains demonstrated adherence to Caco-2/TC-7 cells (33-100%) and effectively inhibited Salmonella invasion. Among the treatments, co-culture showed the greatest effect, reducing Salmonella association and invasion by more than 50%. Additionally, these yeasts modulated the epithelial immune response, significantly decreasing CCL20-driven luminescence by 60-81% (p < 0.0001). These results highlight the potential of yeasts from fermented beverages as probiotics to counteract Salmonella infections, offering a promising alternative in the fight against antibiotic resistance.

The Role of Gut Microbiota Modification in Nonalcoholic Fatty Liver Disease Treatment Strategies

One of the most common chronic liver diseases is nonalcoholic fatty liver disease (NAFLD), which affects many people around the world. Gut microbiota (GM) dysbiosis seems to be an influential factor in the pathophysiology of NAFLD because changes in GM lead to fundamental changes in host metabolism. Therefore, the study of the effect of dysbiosis on the pathogenicity of NAFLD is important. European clinical guidelines state that the best advice for people with NAFLD is to lose weight and improve their lifestyle, but only 40% of people can achieve this goal. Accordingly, it is necessary to provide new treatment approaches for prevention and treatment. In addition to dietary interventions and lifestyle modifications, GM modification-based therapies are of interest. These therapies include probiotics, synbiotics, fecal microbiota transplantation (FMT), and next-generation probiotics. All of these treatments have had promising results in animal studies, and it can be imagined that acceptable results will be obtained in human studies as well. However, further investigations are required to generalize the outcomes of animal studies to humans.

In Vitro Probiotic Characterization of Yeasts with their Postbiotics' Antioxidant Activity and Biofilm Inhibition Capacity

This study evaluated the in vitro probiotic potential and postbiotic properties of yeast strains isolated from traditional fermented foods, emphasizing antioxidant activity (AOA) and biofilm inhibition capacity (BIC). The yeasts were molecularly confirmed using start codon targeted polymorphisms as Kluyveromyces lactis (n = 17), Saccharomyces cerevisiae (n = 9), Pichia kudriavzevii (n = 6), P. fermentans (n = 4), Wickerhamomyces anomalus (n = 2), and Torulaspora delbrueckii (n = 1). The probiotic assessment of live cells included viability in simulated gastric and pancreatic juices, autoaggregation, hydrophobicity, and AOA, using S. boulardii MYA-796 as reference. Additionally, cell-free supernatants (CFS) were tested for AOA and BIC against Cronobacter sakazakii, Listeria monocytogenes, Pseudomonas aeruginosa, and Staphylococcus aureus. Several strains exhibited significantly higher in vitro probiotic characteristics compared to S. boulardii MYA-796 (P < 0.05), particularly in gastric and pancreatic survival, hydrophobicity, and AOA. Notably, CFS exhibited greater AOA than live cells and strong BIC, especially against L. monocytogenes and S. aureus. Multivariate analysis identified K. lactis TC11, S. cerevisiae M33T1-2, P. kudriavzevii S96, W. anomalus OB7Y1, and T. delbrueckii KY31 as having superior probiotic properties, attributed to enhanced gastric survival, autoaggregation, and AOA. CFS of S. cerevisiae M33T1-2 and T. delbrueckii KY31 demonstrated significant BIC, with over 60% inhibition across all tested pathogens.

Novel Insights in the Application of Probiotic Yeast Saccharomyces boulardii in Dairy Products and Health Promotion

Probiotic organisms are increasingly being incorporated into foods in order to develop products to prevent and reduce many diseases. Saccharomyces boulardii, a probiotic yeast with unique properties, such as viability over a wide pH range, antibiotic resistance, and the ability to reach a steady state, has an advantage over bacterial probiotics. The present review highlights the potential application of S. boulardii in functional fermented dairy products and the genetic engineering of this probiotic microorganism as a therapeutic agent for the treatment of various infectious diseases. It was found that probiotic yeast stimulates the growth of lactic acid bacteria in dairy products, creating favorable conditions and positively affecting the product's sensory characteristics. Moreover, its viability of more than 106 cfu/mL at the end of the yogurt shelf life confirms its probiotic effect. On the other hand, there is a growing interest in the design of probiotic strains to improve their characteristics and fill existing gaps in their spectrum of action such as the inhibition of some bacterial toxins, as well as anti-inflammatory and immunomodulatory effects. The strengthening of immune functions and effective therapies against various diseases by S. boulardii was confirmed. However, considering this yeast species' potential, further research is necessary to accurately determine the functional properties in terms of incorporation into food matrices and from the aspect of health and well-being claims.

Probiotic Properties and Safety Evaluation in the Invertebrate Model Host Galleria mellonella of the Pichia kudriavzevii YGM091 Strain Isolated from Fermented Goat Milk

Potential probiotic yeast strains isolated from fermented food need to meet safe and beneficial conditions for the host's health. The Pichia kudriavzevii YGM091 strain isolated from fermented goat milk has outstanding probiotic characteristics, including: the high survival percentage in digestive system conditions (reaching up 247.13 ± 0.12 and 145.03 ± 0.06% at pH 3.0 and bile salt 0.5%, respectively); good tolerance to temperature, salt, phenol, ethanol; good surface properties such as high hydrophobicity percentage (> 60%), the high auto-aggregation percentage rate (66.56 ± 1.45% after 45 min of incubation) and the high co-aggregation percentage rate with pathogenic bacteria in a short time (> 40% after 2 h of incubation); biofilm forming after 24 h of incubation on abiotic surfaces; antioxidant activity reached excellent level after only 24 h of incubation (The percentage free radical scavenging and the Trolox equivalent reaching up 79.86 ± 0.70% and 92.09 ± 0.75 µg/mL after 72 h of incubation); extracellular enzymes production protease and cellulase with high activity, amylase and pectinase with moderate activity and non-lipase activity. Simultaneously, the YGM091 strain is the in vitro safety yeast: insensitive to antibiotics and fluconazole, negative for gelatinase, phospholipase, coagulase, and non-hemolysis activities. Furthermore, this strain is in vivo safety yeast with the dosages below 106 CFU/larva in the Galleria mellonella model with over 90% survival larvae and the yeast density reduced to just 102-103 CFU/larva after 72 h post-injection. Research results have demonstrated that the Pichia kudriavzevii YGM091 strain is a safe potential probiotic yeast and could become a candidate probiotic food to be used in the future.

The supplementation of female dogs with live yeast Saccharomyces cerevisiae var. boulardii CNCM I-1079 acts as gut stabilizer at whelping and modulates immunometabolic phenotype of the puppies

Time around parturition is a stressful period for both bitches and their puppies. The use of probiotics has been proposed, e.g., in pigs, to improve health status of sows, their reproductive performances and in turn, the health and performance of their progeny. The objective of the present study was to evaluate the impact, on both dams and puppies, of a supplementation of bitches with the live yeast Saccharomyces cerevisiae var. boulardii CNCM I-1079 (SB-1079) during the second part of the gestation and the lactation period. A total of 36 bitches of medium and large-sized breeds were enrolled. They were divided into two groups, one of which received 1.3 × 109 colony forming units of live yeast per day. At dam's level, SB-1079 yeast shaped a different microbiota structure between the two groups just after whelping, impacted alpha diversity and some plasma metabolites related to energy metabolism. Regarding reproductive performances, SB-1079 improved gross energy of the colostrum (1.4 vs. 1.2 kcal of ME/g) as well as the concentration of protein in milk at Day 7 after parturition (10.4 vs. 7.6%). SB-1079 also reduced the odds of having low birth weight in the litter. At puppy's level, a modulation of immunometabolic phenotype is suggested by the observation of increased growth rates during the early pediatric period (i.e., between 21 and 56 days of life, 225 vs. 190%) and a decrease of the IL-8:IL-10 ratio after vaccination against rabies (4.2 vs. 16.9). Our findings suggest that SB-1079 supplementation during gestation and lactation has the potential to enhance health of bitches and in turn health of puppies through maternal programming.

Anticancer Properties of Saccharomyces boulardii Metabolite Against Colon Cancer Cells

Saccharomyces cerevisiae var. boulardii has been used as a probiotic yeast in the medical and food industries. Colon cancers have been known as the third most common cancer type worldwide. Nowadays, cell-free extract and metabolites of probiotics have been employed for the treatment or prevention of different cancer diseases. This study investigates the anticancer properties of S. boulardii metabolites against human colon carcinoma. We evaluated cytotoxicity, apoptosis induction, and suppression of survivin, IL-8, and NFƙB gene expression effects of SBM against caco-2 cells after 24 and 48 h. IC50 concentrations of SBM were measured at 815 and 1411 µg/mL for 24 and 48 h treatments, respectively. The total proportion of apoptotic caco-2 cells treated with SBM after 24 and 48 h were calculated at 62.23 and 88.7%, respectively. Also, relative expression of survivin, IL-8, and NFƙB genes were significantly suppressed in caco-2 cells treated with SBM after 24 and 48 h. In conclusion, we found that SBM induced apoptosis, inhibited the growth rate, and suppressed the expression of the survivin, IL-8, and NFƙB genes in human colorectal cancer cells and it can be considered as a perspective supplement or drug for the treatment or prevention of colon cancer in humans.

Injectable Living Probiotic Dressing Built by Droplet-Based Microfluidics and Photo-Cross-Linking to Prevent Pathogenic Infection and Promote Wound Repair

The treatment of infected wounds faces great challenges due to the emergence of antibiotic resistance and the lack of persistence in drug release. Here, a living probiotic dressing is constructed by integrating droplet-shearing and photo-cross-linking. Saccharomyces boulardii (S. boulardii), the only probiotic used clinically, is encapsulated and attached to a wound under light irradiation. A double-layer hydrogel provides a protective barrier for cell growth and proliferation while preventing the escape of S. boulardii. The living probiotic dressing shows superior biosafety with fibroblast cells. Strikingly, in vitro and in vivo experiments indicate that the living probiotic dressing not only inhibits bacterial survival and colonization, but also alleviates inflammation and accelerates wound closure. More significantly, the living probiotic dressing promotes collagen deposition and neovascularization, which accelerates wound healing. This work can provide new ideas for clinical wound treatment and widen the application of probiotics in tissue engineering.

Live Yeast (Saccharomyces cerevisiae var. boulardii) Supplementation in a European Sea Bass (Dicentrarchus labrax) Diet: Effects on the Growth and Immune Response Parameters

The present study has been aimed at evaluating the effects of the dietary inclusion of the live yeasts, Saccharomyces cerevisiae var. boulardii (LSB) administered at increasing concentrations (0, 100, and 300 mg kg-1 of feed, here referred to as LSB 0, 100, 300) for 90 days, on the health conditions of European sea bass. The main zootechnical parameters, histological and morphological analyses, innate immunity response parameters (intestinal cytokine expression, lysozyme content, spontaneous hemolytic and hemagglutinating activities, antibacterial activities, and peroxidase activity) were measured as fish welfare parameters. LSB did not impair either growth parameters or the morphometric indexes. LSB down-regulated interleukin-1β transcription in the distal gut of fish treated with 5.4 × 105 CFU g-1 (LSB100) for 21 days. The interleukin-6 mRNA level decreased significantly in the proximal gut for both doses of yeast, after 21 days of feeding; the gene expression of interleukin-6 was significantly lower in the sea bass fed 10.81 × 105 CFU g-1 (LSB300) probiotic. The levels of TNF-α mRNA were not influenced by probiotic supplementation. Increases, although not significant, in the hematological and immunological parameters were also recorded. The data collected in the present study suggests that an LSB-supplemented diet acts on the gut immune system of sea bass by modulating the expression of the key inflammatory genes.

Antifungal bio-coating of endotracheal tube built by overexpressing the MCP1 gene of Saccharomyces boulardii and employing hydrogel as a "house" to antagonize Candida albicans

BACKGROUND

For some ICU patients, an artificial airway must be established with an endotracheal tube, but Candida albicans can easily adhere to the tube surface and form a biofilm, leading to potentially life threatening fungal infections. Therefore, it is urgent to prevent and reduce C. albicans infections introduced by the endotracheal tube. However, there are few antifungal drugs effective against C. albicans, and each of these drugs may have adverse effects on human cells. Saccharomyces boulardii is regarded as an alternative strategy to inhibit the adhesion of C. albicans, but it is affected by environmental stress. We hypothesized that it is feasible to strengthen the antagonistic ability of S. boulardii via encapsulating and genetically modification.

METHODS

In this study, a bioactive material carrying the overexpressed MCP1 gene of Saccharomyces boulardii was constructed based on one-step photo-crosslinking. This material achieved spatial growth control of S. boulardii by encapsulating each S. boulardii cell within a hydrogel pore. The bioactive material was coated on an endotracheal tube and tested for its ability to inhibit the adhesion of C. albicans. Additionally, the material's antagonistic activity towards C. albicans was evaluated by detecting intracellular Adenosine-triphosphate content, reactive oxygen species level and the activity of antioxidative enzymes. Tissue invasion experiment was executed to further evaluate the anti-adhesion ability of S. boulardii bio-coating.

RESULTS

Encapsulating the overexpression of MCP1 by S. boulardii in hydrogel pores enhanced the viability of probiotics in the presence of high salt and oxidation stress. When used as the coating of an endotracheal tube, the S. boulardii bioactive material efficiently inhibited the adhesion of C. albicans by impairing the activities of superoxide dismutase and catalase and disturbing mitochondrial functions. In vivo, the S. boulardii bioactive material coating displayed good biocompatibility and reduced the host tissue invasion and virulence of C. albicans.

CONCLUSIONS

The integration of genetic modification and immobilization model breaks the bottleneck of previous application of microorganisms, and provides a new way to prevent fungal infections introduced by endotracheal tubes.

Protective effects of Aureobasidium pullulans lysate on UV-damaged human skin fibroblasts and HaCaT cells

BACKGROUND

Aureobasidium pullulans (A. pullulans) has a wide range of applications. Ultraviolet (UV) rays from the sun can cause skin photoaging. In order to explore the protective effect and application potential of A. pullulans lysate on UV-damaged human skin fibroblasts (HSF) and HaCaT Cells, this study investigates the anti-aging and anti-inflammatory effects of A. pullulans lysate as well as the mechanism of anti-oxidative stress at the cellular and molecular levels through cytotoxicity experiments, enzyme-linked immunosorbent assays (ELISA), and real-time quantitative PCR (RT-qPCR).

RESULTS

The experimental results have shown that the A. pullulans lysate can effectively reduce the loss of extracellular matrix components (EMC), such as collagen and hyaluronic acid (HA). It is also capable of scavenging excess reactive oxygen species (ROS) from the body, thereby increasing the activity of catalase, decreasing the overexpression of intracellular matrix metalloproteinases (MMPs), enhancing the gene expression of metalloproteinase inhibitors (TIMPs), and decreasing the level of inflammatory factors, reducing UV-induced apoptosis of HaCaT cells. Meanwhile, oxidative stress homeostasis is also regulated through the Nrf2/Keap1 and MAPK signaling pathways.

CONCLUSIONS

This study shows that the A. pullulans lysate has the potential to resist photoaging.

Investigating the Efficacy of Saccharomyces boulardii in Metabolic Syndrome Treatment: A Narrative Review of What Is Known So Far

Metabolic syndrome (MetS) is characterized by complex metabolic changes involving a cluster of co-occurring conditions, such as abdominal obesity, high blood pressure, high fasting plasma glucose, high serum triglycerides, and high LDL cholesterol levels or low HDL cholesterol levels. The incidence and risk factors of MetS occurrence increase every year. It is estimated that MetS affects approximately 30% of the population of some countries. Therefore, novel strategies are being studied to reduce the negative impact of having an unbalanced diet and a lack of physical activity. One of these strategies is the administration of probiotic microorganisms, such as the yeast Saccharomyces boulardii, which has been associated with several beneficial health effects (including modulation of the intestinal microbiota and improvement of the inflammatory, antioxidant, antibacterial, antitumor, and anti-inflammatory profiles). Thus, the objective of this study was to review the risk factors of MetS occurrence and the beneficial effects of S. boulardii ingestion in the treatment of MetS. Here, we critically evaluate the treatment necessary to promote these benefits. Using the pre-established inclusion criteria, eight studies were reviewed, including five animal and three human studies. The results reported the regulation of the lipid profile, modulation of the intestinal microbiota and gene expression, and a decrease in mass gain as positive results when S. boulardii was administered. Although more experiments are needed to validate these results, especially using human models, there is a trend toward improvement in MetS and a reduction in its risk factors with the administration of S. boulardii.

Promising Probiotic Properties of the Yeasts Isolated from Rabilé, a Traditionally Fermented Beer Produced in Burkina Faso

In recent years, research on yeasts as probiotics has gained more and more interest, which will allow the development of "new" products in the probiotics market. In this context, seventeen yeast strains isolated from Rabilé, a traditional beer produced in Burkina Faso, were assessed for their probiotic attributes. The yeast identification was performed by molecular methods, including PCR-RFLP and 5.8S-ITS region sequencing. Saccharomyces cerevisiae (14 strains) was the predominantly identified species, followed by Pichia kudriavzevii (2 strains) and Rhodotorula mucilaginosa (1 strain). Except for R. mucilaginosa, all yeast strains grew well at human temperature. The yeast strains showed high resistance when they were exposed to simulated gastrointestinal conditions. Auto-aggregation ability was between 70.20 ± 10.53% and 91.82 ± 1.96%, while co-aggregation with E. coli ranged from 24.92 ± 3.96% to 80.68 ± 9.53% and with S. enterica serovar Typhimurium from 40.89 ± 8.18% to 74.06 ± 7.94%. Furthermore, the hydrophobicity of isolated strains toward n-hexane was in the range from 43.17 ± 5.07% to 70.73 ± 2.42%. All yeast strains displayed high antioxidant capabilities, and the strains did not show hemolysis halos, such that they can be considered safe. Additionally, S. cerevisiae strains strongly inhibited the growth of foodborne pathogens. This is the first preliminary study to identify and characterize the yeast strains isolated from Rabilé with interesting probiotic properties.