Probiotic Yeast Research Articles

Advances in Yeast Probiotic Production and Formulation for Preventative Health

The use of probiotics has been gaining popularity in terms of inclusion into human diets over recent years. Based on properties exerted by these organisms, several benefits have been elucidated and conferred to the host. Bacteria have been more commonly used in probiotic preparations compared to yeast candidates; however, yeast exhibit several beneficial properties, such as the prevention and treatment of diarrhea, the production of antimicrobial agents, the prevention of pathogen adherence to intestinal sites, the maintenance of microbial balance, the modulation of the immune system, antibiotic resistance, amongst others. Saccharomyces boulardii is by far the most studied strain; however, the potential for the use of other yeast candidates, such as Kluyveromyces lactis and Debaryomyces hansenii, amongst others, have also been evaluated in this review. Furthermore, a special focus has been made regarding the production considerations for yeast-based probiotics and their formulation into different delivery formats. When drafting this review, evidence suggests that the use of yeasts, both wild-type and genetically modified candidates, can extend beyond gut health to support skin, the respiratory system, and overall immune health. Hence, this review explores the potential of yeast probiotics as a safe, effective strategy for preventative health in humans, highlighting their mechanisms of action, clinical applications, and production considerations.

Heterologous expressing melittin in a probiotic yeast to evaluate its function for promoting NSC-34 regeneration

Melittin is a bioactive peptide and the predominant component in bee venom (BV), studied for its many medical properties, such as antibacterial, anti-inflammatory, anti-arthritis, nerve damage reduction, and muscle cell regeneration. Melittin is primarily obtained through natural extraction and chemical synthesis; however, both methods have limitations and cannot be used for mass production. This study established a heterologous melittin expression system in the probiotic yeast Kluyveromyces marxianus. This yeast was selected for its advantages in stress tolerance and high secreted protein yields, simplifying purification. A > 95% high-purity melittin (MET) and its precursor promelittin (ProMET) were successfully produced and purified at 1.68 μg/mL and 3.33 μg/mL concentrations and verified through HPLC and mass spectrum. The functional test of the NSC-34 cell regeneration revealed that MET achieved the best activity compared to ProMET and the natural-extracted BV groups. Growth-related gene expressions were evaluated, including microtubule-associated protein 2 (MAP2), microtubule-associated protein Tau (MAPT), growth-associated protein 43 (GAP-43), choline acetyltransferase (ChAT), vesicular acetylcholine transporter (VAChT), and acetylcholine esterase (AChE). The results indicated that treating MET increased MAP2, GAP-43, and VAChT expressions, in which cholinergic signaling is related to neurological functions. A heterologously expressed melittin in a probiotic yeast and its potential for promoting NSC-34 regeneration described here facilitate commercial and therapeutic use.Key points• MET and its precursor ProMET were successfully hetero-expressed in K. marxianus• > 95% high-purity MET and ProMET were purified at 1.68 μg/mL and 3.33 μg/mL• MET has no cytotoxicity toward NSC-34 and significantly promotes NSC-34 growth

Does the Use of the Yeast Probiotic Saccharomyces cerevisiae Actisaf Sc 47 Reduce the Environmental Impacts of Beef Cattle? A Study Based on Life Cycle Assessment

Increasing animal protein, especially from beef, is necessary to satisfy the requirements of the growing global population. However, this is becoming increasingly challenging due to stakeholders prioritizing sustainable systems with low environmental impacts. To answer these challenges, the use of feed additives such as yeast probiotics seems to be an effective route for improvements in feed efficiency and growth performance. The current study was performed to quantify the environmental impacts of the production and use of a yeast probiotic (Actisaf® Sc 47) through an LCA method in four trials performed during the fattening period: France (French trial), Spain (Spanish trial), and Italy (Italian trials A and B). During each trial, two groups of animals with the same characteristics were compared during the fattening period: the control group without Actisaf® Sc 47 supplementation used as a baseline, and the experimental group with Actisaf® Sc 47 supplementation. The calves started the trial at the ages of 224, 92, and 186 days during the French, Spanish, and Italian trials A and B, respectively. Of the sixteen impact category indicators, nine were analyzed. In Italian trials A and B, the Spanish trial, and the French trial, the use of Actisaf® Sc 47 reduced CC by 4.8, 3.8, 6.6, and 5.4%; FE by 4.8, 3.9, 8.2, and 6.3%; ME by 4.9, 4.0, 6, and 6.4%; and TE by 5.3, 4.1, and 6.2%, respectively. Moreover, during the same trials, Actisaf® Sc 47 reduced AC by 6.0, 4.1, 6.3, and 7.1%; LU by 4.7, 3.9, 5.8, and 6.1%; WU by 4.5, 3.4, 5.2, and 5.9%; RU (fossils) by 4.8, 3.7, 7.3, and 4.8%; and PM by 5.2, 4.1, 6.3, and 7.1%, respectively. The use of Actisaf® Sc 47 has beneficial effects on the environment. Regarding Actisaf® Sc 47 production, the results showed that the production of 1 kg of Actisaf® Sc 47 emitted 2.1 kg of CO2 eq, 60% of which came from the fermentation process and 39% from drying. The results demonstrate the interest in using Actisaf® Sc during the fattening period for its multiple positive outcomes: improving performance and efficiency, while reducing the global carbon footprint.

Effect of yeast probiotics in lactation and yeast cell-wall prebiotic and Bacillus subtilis probiotic in nursery on lifetime growth performance, immune response, and carcass characteristics.

Twenty-eight mixed parity sows (Line 241; DNA) and their offspring were used to evaluate live yeast supplementation during lactation with or without a pre/probiotic combination during the nursery period on lactation performance, lifetime growth performance, and immune response. On d 110 of gestation, sows were allotted to a lactation diet with or without a live yeast probiotic (0.10% Actisaf Sc 47 HR+; Phileo by Lesaffre, Milwaukee, WI). At weaning, their offspring (350 pigs; initially 6.1 ± 0.02kg) were randomly assigned in a 2 × 2 factorial with main effects of sow treatment and nursery treatment consisting of a control diet or a diet with a yeast cell-wall prebiotic and Bacillus subtilis probiotic (0.10% YB; Phileo by Lesaffre, Milwaukee, WI) fed for 42 d followed by common diets fed until marketing. Two nursery pens were combined into 1 finishing pen, such that there were 5 and 10 pigs per pen with 17 or 18 and 8 or 9 replications per treatment during the nursery and finishing periods, respectively. There were no significant effects of yeast supplementation on lactation performance (P ≥ 0.079). There was a sow × nursery diet interaction (P = 0.024) on nursery ADG. Pigs from yeast fed sows had increased ADG when fed control nursery diets compared to pigs from control sows fed the control nursery diet with pigs fed pre/probiotic nursery diets intermediate, regardless of sow diet. Pigs from yeast fed sows tended (P = 0.067) to have greater final BW (d 165). A subset of pigs was sampled throughout their lifetime to determine serum porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae antibody sample-to-positive (S/P) ratios and percentage inhibition of Lawsonia intracellularis. There was a tendency for a PCV2 S/P ratio sow diet × day interaction (P = 0.097) where progeny from yeast fed sows had higher PCV2 S/P ratios at 101 d of age compared to control sow progeny (P = 0.046). There was a PCV2 S/P ratio nursery diet × day interaction (P = 0.036) where pigs fed a pre/probiotic combination had reduced S/P ratios at 66, 78, and 162 d of age (P ≥ 0.022); however, at 22 d of age pigs fed a pre/probiotic combination tended to have an increased S/P ratio (P = 0.051). In conclusion, effects of combining a yeast probiotic in lactation diets and a pre/probiotic in nursery diets were not additive. However, feeding a live yeast probiotic during lactation resulted in tendencies (P ≥ 0.10) for increased progeny final BW and HCW.

Probiotic yeast characterization and fungal amplicon metagenomics analysis of fermented bamboo shoot products from Arunachal Pradesh, northeast India

This study investigates the diverse fungal community and their probiotic functions present in ethnic fermented bamboo shoots of Arunachal Pradesh. Among 95 yeast isolates, 13 demonstrated notable probiotic attributes. These included growth at pH 3, bile tolerance, autoaggregation, co-aggregation, hydrophobicity, lysozyme tolerance and antimicrobial activity. Confirmation of some of the probiotic properties through specific primers enabled the detection of genes associated with acid and bile tolerance, antimicrobial activity, and adhesion. Probiotic yeasts were finally identified based on D1 and D2 sequences of large ribosomal subunit as Meyerozyma guilliermondii (BEP1, KGM1_3, NHR3), Meyerozyma caribbica (GEP7), Candida orthopsilopsis (ES1_2, EB1_2, EEGM2_4, GEP2, NEK9), Candida parasilopsis (HD1_1), Pichia kudriavzevii (NHR12), Pichia fermentans (BEP2), and Saccharomyces cerevisiae (NEP2). Fungal amplicon sequencing highlighted the predominance of Ascomycetes, particularly Pestalotiopsis and Penicillium genera. In this study we have perfomed a culture dependent isolation and probiotic study of yeasts and culture independent analysis of the fungal community present during the fermentation of bamboo shoots of Arunachal Pradesh which provides information about the beneficial properties of bamboo shoots as the reservoir of probiotic microorganisms.

Assessment of Potential Probiotic Yeasts Isolated from The Small Intestines of Cattle in Thailand

Y easts are widely studied and considered good candidates for probiotics due to their numerous benefits. This study aimed to investigate potential probiotic attributes of yeasts isolated from the small intestines of cattle in Thailand. Growth at body temperature, resistance to low pH, auto-aggregation capability, hydrophobicity, growth under gastrointestinal tract (GIT) conditions, safety profiles, antimicrobial activity, and extracellular enzyme production of yeast strains were evaluated in vitro. The results of sequential screening indicated that 829 out of 1,025 yeast strains could grow at both 37 and 39 °C, 682 strains could resist acidity at pH 2 for 24 h, 252 strains revealed greater than 83% auto-aggregation capability, and 97 strains showed higher than 90% hydrophobicity. Sixty strains grew well under simulated GIT conditions in the presence of pepsin, pancreatin, and bile salts. Thirteen strains of Diutina rugosa showed negative results for hemolytic, gelatinase, and phospholipase activities, while seven strains of Pichia kudriavzevii also showed negative results for the above activities, except for phospholipase. Neither D. rugosa nor P. kudriavzevii inhibited Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Additionally, 12 strains of D. rugosa and four strains of P. kudriavzevii produced phytase and cellulase, while only D. rugosa PCD3-6 exhibited protease and phytase activities. Therefore, D. rugosa (strains PCD3-6, PCD93-19, PYJ93-7, PYJ93-16, PCJ94-4, PCJ94-6, PCJ94-10, PYD100-8, CTD93-1, CTD93-2, CTJ93-5, CTJ93-6, and YTJ97-4) and P. kudriavzevii (strains PYI3-3, PCI3-4, PCJ90-7, and PYI91-15) were proposed as potential probiotic yeasts. They may be beneficially applied as feed additives to improve nutritional value and quality, thereby enhancing animal performance and health. Moreover, this work indicated useful preliminary results that could be a baseline for future research in human probiotic applications.

Co-Encapsulation of Coffee and Coffee By-Product Extracts with Probiotic Kluyveromyces lactis.

Coffee and coffee by-products contain several chemical compounds of great relevance, such as chlorogenic acid (CGA), trigonelline, and caffeine. Furthermore, yeasts have been the target of studies for their use as probiotics because of their interesting biochemical characteristics. The combined administration of probiotic microorganisms with components that provide health benefits mediated by alginate encapsulation is an alternative that ensures the stability of cells and chemical compounds. In this context, the aim of this work was to co-encapsulate the probiotic yeast Kluyveromyces lactis B10 and extracts of green coffee beans, coffee silverskin, and PVA (black, green or immature, and sour coffee beans). The bioactive composition, antioxidant and antimicrobial activities of the extracts, microcapsule morphological characteristics and encapsulation efficiency, ability of the encapsulation to protect the yeast cells subjected to gastrointestinal conditions, and antioxidant activity of the microcapsules were evaluated. All the evaluated extracts showed antioxidant activity, of which PVA showed 75.7% and 77.0%, green coffee bean showed 66.4% and 45.7%, and coffee silverskin showed 67.7% and 37.4% inhibition of DPPH and ABTS•+ radicals, respectively, and antimicrobial activity against the pathogenic bacteria E. coli, Salmonella, and S. aureus, with high activity for the PVA extract. The microcapsules presented diameters of between 1451.46 and 1581.12 μm. The encapsulation efficiencies referring to the yeast retention in the microcapsules were 98.05%, 96.51%, and 96.32% for green coffee bean, coffee silverskin, and PVA, respectively. Scanning electron microscopy (SEM) showed that the microcapsules of the three extracts presented small deformations and irregularities on the surface. The K. lactis cells encapsulated in all treatments with the extracts showed viability higher than 8.59 log CFU/mL, as recommended for probiotic food products. The addition of green coffee bean, coffee silverskin, and PVA extracts did not reduce the encapsulation efficiency of the alginate microcapsules, enabling a safe interaction between the extracts and the K. lactis cells.

Assessment of selenium-enriched deactivated probiotic yeast efficiency in patulin detoxification in apple juice

Patulin (PAT) contamination in fruits, particularly apples and their products, poses a significant health hazard. This research aimed to eliminate PAT from simulated juice solution and actual apple juice using live and ultrasonically deactivated (D) probiotic yeasts, specifically Saccharomyces cerevisiae (S.c) and Saccharomyces boulardii (S.b) yeasts enriched with selenium (Se). The Se-enriched yeasts were analyzed using various techniques including Fourier transform infrared spectrometer (FT-IR), energy-dispersive X-ray analysis (EDX), scanning electron microscopy (SEM), and Inductively coupled plasma–optical emission spectroscopy (ICP-OES). The study assessed the effects of yeast type, contact time (2–18 h), ultrasound treatment, and initial concentration of PAT (50–150 μg.L−1) on PAT adsorption. The most effective treatment involved the Se-S.b-D yeast strain, with an initial PAT concentration of 50 μg.L−1 for 10 h, exhibiting notable toxin removal percentages in both the apple juice simulator (98.27% reduction equivalent to 49.135 μg.L−1) and real apple juice (87.19%). The detoxification outcomes were consistent with pseudo-second-order kinetic and Langmuir isotherm models, indicating that Se-S.b-D is a biocompatible and low-cost strain with high efficiency to remove PAT in aqueous solutions.

33 Beyond bacteria: Impact of live yeast as a probiotic on the intestinal health of dogs

Abstract Inactivated yeast and yeast-based products are commonly used in pet food to improve palatability, contribute to dietary protein content, and improve gastrointestinal functionality. However, the use of viable yeast Saccharomyces as a probiotic may contribute to additional beneficial effects on dogs and cats. Considering that, in this presentation, we will focus on the use of viable yeast as a probiotic for dogs. A study conducted at the Federal University of Parana, Brazil, observed that Beagle dogs supplemented with a probiotic yeast presented reduced fecal concentrations of total biogenic amines, ammonia, and aromatic compounds and greater fecal concentrations of butyrate. The supplemented dogs also presented an improvement in dysbiosis index, a greater abundance of Bifidobacterium and Turicibacter, and a reduced abundance of Escherichia coli in feces. In addition, control group dogs presented upregulation in microbial genes related to virulence factors (such as lipopolysaccharide export system), antibiotic resistance, and osmotic stress, compared with the probiotic group. These results may indicate a possible protective effect of the yeast probiotic against potential pathogenic bacteria in the gut. The mechanisms by which yeast probiotics may contribute to gastrointestinal functionality in dogs and cats are not fully elucidated. However, they are usually attributed to the stimulation of brush edge disaccharidases; competition for adhesion sites against potential pathogens; stimulation of nonspecific immunity; neutralization of toxins; and direct effect against potentially pathogenic microorganisms. Many of these mechanisms are influenced directly by yeast cell wall components, such as mannans and beta-glucans. One of the main mechanisms of action of mannans is the elimination of bacteria with pathogenic potential that present type-1 fimbriae, such as some strains of E. coli and Salmonella, preventing their adhesion and colonization to the host mucosa. This may also contribute to the establishment of beneficial bacteria in the gut. We can conclude that viable yeast Saccharomyces as a probiotic may have promising beneficial effects on intestinal functionality of dogs.

235 Impact of yeast cell wall and probiotics on gut microbiota, immunity, and growth in weaned piglets

Abstract This study investigates the effect of yeast cell wall (YCW) supplementation and multispecies probiotics as alternatives to antibiotic growth promoters (AGPs) on the gut microbiota, immune function, and growth performance in weaned piglets. We utilized a randomized complete block design involving 160 piglets across four treatments during the nursery phase. The treatments administered throughout the experimental period were as follows: CONT+ = basal diet with Halquinol (AGP); YCW = basal diet with Saccharomyces cerevisiae yeast cell wall at 1 kg/MT; SIM+ = basal diet with YCW at 0.5 kg/MT + multispecies probiotic (Bacillus subtilis 2.0 x 10^9 CFU/g, Bacillus coagulans 5.0 x 10^8 CFU/g, Clostridium butyricum 5.0 x 10^7 CFU/g, and Bacillus licheniformis 2.0 x 10^9 CFU/g) at 0.6 kg/MT; SIM- = basal diet with YCW at 0.5 kg/MT + multispecies probiotic at 0.3 kg/MT. Methodologies include daily feed intake, body weight gain measurement, feed conversion ratio (FCR), diarrhea scoring, serum cytokine and chemokine concentration, and microbiome analysis. Throughout the study period (21 to 63 d), only FCR showed differences (P = 0.0076). CONT+ and YCW demonstrated better FCRs, at 1.543 and 1.585 respectively, without significant variation between them, while SIM- lagged with the least favorable outcome at 1.654 (Table 1). At 35 d, IL-10 concentrations were greatest in the SIM- group, showing a 271.25% increase compared with other treatments (Figure 2). At 49 d, IL-8 was least in the YCW group, with a 247% reduction compared with CONT+, while SIM+ and SIM- showed no significant differences compared with other treatments (Figure 1). The Firmicutes/Bacteroidota (F/B) ratio shows that the CONT+ treatment was inferior compared with the YCW, SIM+, and SIM- treatments (Figure 3). The Lactobacillaceae family differed between CONT+ and the YCW, SIM+, and SIM- treatments, with the greatest abundance in the SIM+ treatment, followed by SIM- and YCW (Figure 4). The genera Lactobacillus differed between the CONT+ treatment compared with the YCW, SIM+, and SIM- treatments. Prebiotics, whether used alone or combined with probiotics, serve as effective substitutes for AGPs, boosting the health and performance of piglets throughout the nursery phase.

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.

Encapsulation of Saccharomyces spp. for Use as Probiotic in Food and Feed: Systematic Review and Meta-analysis.

Probiotics, particularly yeasts from the genus Saccharomyces, are valuable for their health benefits and potential as antibiotic alternatives. To be effective, these microorganisms must withstand harsh environmental conditions, necessitating advanced protective technologies such as encapsulation to maintain probiotic viability during processing, storage, and passage through the digestive system. This review and meta-analysis aims to describe and compare methods and agents used for encapsulating Saccharomyces spp., examining operating conditions, yeast origins, and species. It provides an overview of the literature on the health benefits of nutritional yeast consumption. A bibliographic survey was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. The meta-analysis compared encapsulation methods regarding their viability after encapsulation and exposure to the gastrointestinal tract. Nineteen studies were selected after applying inclusion/exclusion criteria. Freeze drying was found to be the most efficient for cell survival, while ionic gelation was best for maintaining viability after exposure to the gastrointestinal tract. Consequently, the combination of freeze drying and ionic gelation proved most effective in maintaining high cell viability during encapsulation, storage, and consumption. Research on probiotics for human food and animal feed indicates that combining freeze drying and ionic gelation effectively protects Saccharomyces spp.; however, industrial scalability must be considered. Reports on yeast encapsulation using agro-industrial residues as encapsulants offer promising strategies for preserving potential probiotic yeasts, contributing to the environmental sustainability of industrial processes.

Identification of potentially probiotic yeasts from Thayir prepared by Backslopping

Identification of potentially probiotic yeasts from Thayir prepared by Backslopping

Epiphytic Yeasts from South Romania for Preventing Food Microbial Contamination.

Epiphytic yeasts represent an important source for the development of novel strategies aiming to combat food microbial contamination. The present study deals with the characterization of nine yeast strains belonging to Starmerella, Candida, Metschinikowia, Lachancea, Kodamaea and Pichia genera, isolated from the surface of plants from the Botanical Garden "Dimitrie Brandza" (Bucharest, Romania) for use as antimicrobial and probiotic agents. The tests involved the determination of the safe status, cell growth under stress conditions, and activity against pathogenic Candida and bacteria strains, respectively, as well as phytopathogenic filamentous fungi and lipolytic activity. None of the nine strains showed all the characteristics for virulence and pathogenicity, with the rare positive results being explained rather by their adaptability to the habitats of origin. The strains Lachancea thermotolerans CMGB-ST12 and Kodamaea ohmeri CMGB-ST19 grew at 37 °C; Metschnikowia reukaufii CMGB-ST21.2, M. reukaufii CMGB-ST.8.1 and M. reukaufii CMGB ST10 grew in the presence of 10% NaCl, while L. thermotolerans CMGB-ST12 and K. ohmeri CMGB-ST19 tolerated both acidic and alkaline pH values well (3.0 to 12.0). The studied yeast strains showed good antimicrobial activity against Candida krusei, Candida albicans and Gram-negative bacterial strains, with K. ohmeri CMGB-ST19 and Pichia membranaefaciens CMGB-ST53 inhibiting up to 100% the development of filamentous fungi. All the strains produced lipases for tributyrin hydrolysis, the best producer being Starmerella bombi CMGB-ST1, and only Candida magnoliae CMGB-ST8.2 tested positive against other probiotic yeasts. Overall, our nine yeast strains show high potential for industrial applications, for obtaining probiotic products and for preventing the development of a wide range of microbial food contaminants.

Probiotics as a Therapeutic Approach for Non-infectious Gastric Ulcer Management: a Comprehensive Review.

A gastric ulcer is a stomach lining or nearby intestine disruption caused by acid and pepsin. Helicobacter pylori (H. pylori) and NSAIDs are the primary culprits behind stomach infections that can lead to gastric ulcers and other digestive disorders. Additionally, lifestyle choices such as alcohol consumptionand cigarette smoking, stress, and exposure to cold environments can also contribute to non-infectious gastric ulcers. Various treatments are available for gastric ulcers, including antibiotics, anticholinergics, and antacids. However, potential concerns include antibiotic resistance, side effects, and treatment failure. Considering this, there is a need for an alternative approach to manage it. Fortunately, probiotics, typically Lactobacillus and Bifidobacterium, show potential for healing gastric ulcers, offering a non-invasive alternative to conventional treatments. A notable concern arises from applying probiotic bacteria stemming from the propensity of pathogenic bacteria to develop antimicrobial resistance in response to antibiotic therapies. Therefore, the use of yeast becomes more imperative due to its natural resistance to antibacterial antibiotics for antibacterial-treated patients. Probiotic bacteria and yeasts could heal gastric ulcers by regulating the immune response, reducing inflammation, and restoring the balance between defensive and aggressive factors of the gastric layer. This comprehensive review provides an in-depth analysis of the benefits of probiotics and their potential as a therapeutic treatment for non-infectious gastric ulcers, along with other probiotic options. In particular, this review provides a succinct summary of multiple literature studies on probiotics, emphasising the distinctive properties of yeast probiotics, as well as their (bacteria and yeasts) application in the management of non-infectious gastric ulcers.

Potential of Non-Saccharomyces Yeasts as Probiotics and Alternatives to Antibiotics in Animal Production.

Probiotics are live yeast or bacterial organisms that have beneficial effects on the host. Several microorganisms exhibit probiotic properties, the most common types being lactic acid bacteria, Bifidobacteria, spore-forming bacteria, and some yeast strains. Saccharomyces cerevisiae var. boulardii is the most important probiotic yeast species. However, another group of foodborne microorganisms, the so-called non-Saccharomyces yeasts (NSYs), has recently been re-evaluated and shown to have enormous potential in various fields of application, ranging from food fermentation to human and animal applications. NSYs are able to produce a range of bioactive compounds such as antimicrobials, mannoproteins, enzymes, polyunsaturated fatty acids, essential amino acids, vitamins, and β-glucans, which increases their potential applications as a new class of probiotics and/or alternatives to antibiotics in animal husbandry. In this review, we aim to highlight the potential and benefits of NSYs as probiotics and natural antimicrobials to improve animal health. Furthermore, the use of NSYs as biological alternatives to antibiotics to control foodborne pathogens in animal production is discussed.

Probiotic and Functional Attributes of Yeasts Isolated from Different Traditional Fermented Foods and Products.

Though numerous bacteria have been used as probiotics by industries, at present, Saccharomyces boulardii and Saccharomyces cerevesiae are the only yeast probiotics which are industrially exploited. In view of this, yeast probiotics were isolated from traditional fermented foods and products collected from different parts of Karnataka, India. In this work, we have studied the probiotic attributes of ten yeast isolates isolated from different traditionally fermented foods and products. About 73 yeast isolates were initially isolated by serially diluting the samples and plating on the Potato Dextrose Agar (PDA) plates. The spot assay was performed to screen the yeast isolates against test pathogens. Ten isolates were selected based on their significant antimicrobial activity. These isolates were subjected to biochemical characterization and then assessed for probiotic properties. The ability of probiotics to endure at pH 2.0 and tolerate bile conditions (0.3%) are crucial attributes for the survival in the gastrointestinal tract (GIT). The yeast isolates were also assessed for cell surface hydrophobicity and autoaggregation capabilities. All the ten isolates showed endurance in GIT tract and > 40% of adhesion. The study further examined cholesterol assimilation, antioxidant and antagonistic properties of the yeasts. Subsequently, the molecular characterization was performed by isolating the DNA of yeast isolates by phenol-chloroform method and identified molecularly through sequencing of D1/D2 regions. The isolates tested negative for gelatinase and DNase and were non-haemolytic indicating they are safe for consumption. Among ten isolates, Meyerozyma guillermondii (MYSY23), Meyerozyma caribbica (MYSY22) and Meyerozyma guillermondii (MYSY19) showed significant results for all probiotic and functional characteristics with greater than 65% survivability in GIT tract and > 50% of antagonistic activity against test pathogens and also proved non-cytotoxic and safe. These findings suggest that yeasts with significant probiotic attributes could be recommended for various probiotic application.

A Saccharomyces boulardii-derived antioxidant protein, thioredoxin, ameliorates intestinal inflammation through transactivating epidermal growth factor receptor

Saccharomyces boulardii (Sb) is a probiotic yeast for the treatment of gastrointestinal disorders, including inflammatory bowel disease (IBD). Little is known about the modulatory capacity of the Sb in IBD. Here, we found that oral gavage of Sb supernatant (SbS) alleviated gut inflammation, protected the intestinal barrier, and reversed DSS-induced down-regulated activation of epidermal growth factor receptor (EGFR) in colitis. Mass spectrum analysis showed that thioredoxin (Trx) is one of the critical secreted soluble proteins participating in EGFR activation detected in SbS. Trx exerted an array of significant effects on anti-inflammatory activity, including alleviating inflammation, protecting gut barrier, suppressing apoptosis, as well as reducing oxidative stress. Mechanistically, Trx promoted EGFR ligand gene expression and transactivated EGFR in a concentration-dependent manner. EGFR kinase inhibitor could block Trx-mediated preventive effects of intestinal epithelial injury. Our data suggested that Sb-derived soluble protein Trx could serve as a potential prophylactic, as a novel postbiotic against colitis, which provides a new strategy for the precision prevention and treatment of IBD.

Chemical profiling and probiotic viability assessment in Gueuze-style beer: Fermentation dynamics, metabolite and sensory characterization, and in vitro digestion resistance

Probiotic viability, metabolite concentrations, physicochemical parameters, and volatile compounds were characterized in Gueuze beers formulated with probiotic lactic acid bacteria (LAB) and yeast. Additionally, the sensory profile of the beers and the resistance of the probiotics to digestion were determined. The use of 2 International Bitterness Units resulted in high concentrations of probiotic LAB but a decline in probiotic yeast as pH decreased. Secondary fermentation led to the consumption of maltose, citric acid, and malic acid, and the production of lactic and propionic acids. Carbonation and storage at 4 °C had minimal impact on probiotic viability. The addition of probiotic LAB resulted in a distinct aroma profile with improved sensory characteristics. Our results demonstrate that sour beers produced with probiotic LAB and a probiotic yeast, and fermented using a two-step fermentation process, exhibited optimal physicochemical parameters, discriminant volatile compound profiles, promising sensory characteristics, and high probiotic concentrations after digestion.

Protective role of wood hemicelluloses: Enhancing yeast probiotics survival in spray drying and storage

Wood hemicelluloses, specifically galactoglucomannans (GGM) and glucuronoxylans (GX) are investigated for their efficacy in spray-dried microencapsulation of Saccharomyces cerevisiae subsp. boulardii (SB). This study demonstrated that GGM and GX effectively protected SB during spray drying at feed concentrations of 15 and 20 % and inlet air temperatures of 105 and 140 °C, ensuring survival rates over 90 %, comparable to gum Arabic, with all achieving over 108 cfu/g in the microcapsules. However, GGM and GX were unable to sustain SB viability when the microcapsules were stored at 33 and 75 % RH (22 °C), beyond 21 and 7 days, respectively. When stored at 4 °C, GX demonstrated a greater ability to protect SB than GGM, with log-cycle reductions of 3 and 6, respectively, after two months. Microstructure analyses showed almost all SB were entrapped by wall materials, with many microcapsules having a wall thickness of 1 − 2 µm. Overall, GX is effective for stable yeast probiotic powders, enabling the development of new probiotic enhanced formulations with prolonged viability and stability.