Potential Probiotic Candidates Research Articles

Lactobacillus-derived protoporphyrin IX and SCFAs regulate the fiber size via glucose metabolism in the skeletal muscle of chickens.

The gut microbiota contributes to skeletal muscle energy metabolism and is an indirect factor affecting meat quality. However, the role of specific gut microbes in energy metabolism and fiber size of skeletal muscle in chickens remains largely unknown. In this study, we first performed cecal microbiota transplantation from Chinese indigenous Jingyuan chickens (JY) to Arbor Acres chickens (AA), to determine the effects of microbiota on skeletal muscle fiber and energy metabolism. Then, we used metagenomics, gas chromatography, and metabolomics analysis to identify functional microbes. Finally, we validated the role of these functional microbes in regulating the fiber size via glucose metabolism in the skeletal muscle of chickens through feeding experiments. The results showed that the skeletal muscle characteristics of AA after microbiota transplantation tended to be consistent with that of JY, as the fiber diameter was significantly increased, and glucose metabolism level was significantly enhanced in the pectoralis muscle. L. plantarum, L. ingluviei, L. salivarius, and their mixture could increase the production of the microbial metabolites protoporphyrin IX and short-chain fatty acids, therefore increasing the expression levels of genes related to the oxidative fiber type (MyHC SM and MyHC FRM), mitochondrial function (Tfam and CoxVa), and glucose metabolism (PFK, PK, PDH, IDH, and SDH), thereby increasing the fiber diameter and density. These three Lactobacillus species could be promising probiotics to improve the meat quality of chicken.IMPORTANCEThis study revealed that the L. plantarum, L. ingluviei, and L. salivarius could enhance the production of protoporphyrin IX and short-chain fatty acids in the cecum of chickens, improving glucose metabolism, and finally cause the increase in fiber diameter and density of skeletal muscle. These three microbes could be potential probiotic candidates to regulate glucose metabolism in skeletal muscle to improve the meat quality of chicken in broiler production.

Antimicrobial Activity, Genetic Relatedness, and Safety Assessment of Potential Probiotic Lactic Acid Bacteria Isolated from a Rearing Tank of Rotifers (Brachionus plicatilis) Used as Live Feed in Fish Larviculture.

Aquaculture is a rapidly expanding agri-food industry that faces substantial economic losses due to infectious disease outbreaks, such as bacterial infections. These outbreaks cause disruptions and high mortalities at various stages of the rearing process, especially in the larval stages. Probiotic bacteria are emerging as promising and sustainable alternative or complementary strategies to vaccination and the use of antibiotics in aquaculture. In this study, potential probiotic candidates for larviculture were isolated from a rotifer-rearing tank used as the first live feed for turbot larvae. Two Lacticaseibacillus paracasei and two Lactiplantibacillus plantarum isolates were selected for further characterization due to their wide and strong antimicrobial activity against several ichthyopathogens, both Gram-positive and Gram-negative. An extensive in vitro safety assessment of these four isolates revealed the absence of harmful traits, such as acquired antimicrobial resistance and other virulence factors (i.e., hemolytic and gelatinase activities, bile salt deconjugation, and mucin degradation, as well as PCR detection of biogenic amine production). Moreover, Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR) analyses unveiled their genetic relatedness, revealing two divergent clusters within each species. To our knowledge, this work reports for the first time the isolation and characterization of Lactic Acid Bacteria (LAB) with potential use as probiotics in aquaculture from rotifer-rearing tanks, which have the potential to optimize turbot larviculture and to introduce novel microbial management approaches for a sustainable aquaculture.

Screening and evaluation of a novel nucleotide-degrading Levilactobacillus brevis grx821 with anti-hyperuricemia ability

Hyperuricemia seriously impacts our health and life quality. Probiotics play a vital role in ameliorating hyperuricemia through decrease urate production by purine substance assimilation. However, most research screened probiotics based on the assimilation of purine nucleoside, ignoring nucleotides. Nucleosides are derived from nucleotides. We hypothesized that lactic acid bacteria with the ability of nucleotides assimilation might be better to reduce intestinal absorption of dietary purine substances. In this study, a total of 235 strains of lactic acid bacteria were isolated from Chinese traditional fermented foods and evaluated for their purine nucleotides assimilation ability. A new potential candidate Levilactobacillus (L.) brevis grx821 isolated from naturally fermented soy whey Suanjiangshui, with a strong ability to degrade purine nucleotides and purine nucleosides, effectively reduced the serum levels of UA and creatinine in hyperuricemia mice by 20.76% and 14.38%. Based on the evaluation of antibiotic susceptibility, production of nitrite and biogenic amines, and hemolytic activity, L. brevis grx821 can be considered safe. L. brevis grx821 showed good gastrointestinal tolerance in vitro and cow milk fermentation characteristics, and could be a promising candidate of dietary supplements for prevention of hyperuricemia. This study suggests a novel way screening potential probiotic candidate for hyperuricemia, which has great guiding significance in the dealing with hyperuricemia.

Genomic characterization and probiotic potential assessment of an exopolysaccharide-producing strain Pediococcus pentosaceus LL-07 isolated from fermented meat

BackgroundThe genomic information available for Pediococcus pentosaceus is primarily derived from fermented fruits and vegetables, with less information available from fermented meat. P. pentosaceus LL-07, a strain isolated from fermented meat, has the capability of producing exopolysaccharides (EPS). To assess the probiotic attributes of P. pentosaceus LL-07, we conducted whole-genome sequencing (WGS) using the PacBio SequelIIe and Illumina MiSeq platforms, followed by in vitro experiments to explore its probiotic potential.ResultsThe genome size of P. pentosaceus LL-07 is 1,782,685 bp, comprising a circular chromosome and a circular plasmid. Our investigation revealed the absence of a CRISPR/Cas system. Sugar fermentation experiments demonstrated the characteristics of carbohydrate metabolism. P. pentosaceus LL-07 contains an EPS synthesis gene cluster consisting of 13 genes, which is different from the currently known gene cluster structure. NO genes associated with hemolysis or toxin synthesis were detected. Additionally, eighty-six genes related to antibiotic resistance were identified but not present in the prophage, transposon or plasmid. In vitro experiments demonstrated that P. pentosaceus LL-07 was comparable to the reference strain P. pentosaceus ATCC25745 in terms of tolerance to artificial digestive juice and bile, autoaggregation and antioxidation, and provided corresponding genomic evidence.ConclusionThis study confirmed the safety and probiotic properties of P. pentosaceus LL-07 via complete genome and phenotype analysis, supporting its characterization as a potential probiotic candidate.

Evaluation of Probiotic Properties and Safety of Lactobacillus helveticus LH10 Derived from Vinegar through Comprehensive Analysis of Genotype and Phenotype.

The probiotic potential of Lactobacillus helveticus LH10, derived from vinegar Pei, a brewing mixture, was assessed through genotype and phenotype analyses. The assembled genome was comprised of 1,810,276 bp and predicted a total of 2044 coding sequences (CDSs). Based on the whole genome sequence analysis, two bacteriocin gene clusters were identified, while no pathogenic genes were detected. In in vitro experiments, L. helveticus LH10 exhibited excellent tolerance to simulated gastrointestinal fluid, a positive hydrophobic interaction with xylene, and good auto-aggregation properties. Additionally, this strain demonstrated varying degrees of resistance to five antibiotics, strong antagonistic activity against four tested pathogens, and no hemolytic activity. Therefore, L. helveticus LH10 holds great promise as a potential probiotic candidate deserving further investigation for its beneficial effects on human health.

Akkermansia muciniphila: a potential candidate for ameliorating metabolic diseases.

Metabolic diseases are comprehensive disease based on obesity. Numerous cumulative studies have shown a certain correlation between the fluctuating abundance of Akkermansia muciniphila and the occurrence of metabolic diseases. A. muciniphila, a potential probiotic candidate colonized in the human intestinal mucus layer, and its derivatives have various physiological functions, including treating metabolic disorders and maintaining human health. This review systematically explicates the abundance change rules of A. muciniphila in metabolic diseases. It also details the high efficacy and specific molecules mechanism of A. muciniphila and its derivatives in treating obesity, type 2 diabetes mellitus, cardiovascular disease, and non-alcoholic fatty liver disease.

Probiotic Characterization of LAB isolated from Sourdough and Different Traditional Dairy Products Using Biochemical, Molecular and Computational Approaches.

The aim of this study was to identify and isolate lactic acid bacteria (LAB) from indigenous sourdough and dairy samples in Iran, and to assess their probiotic properties in vitro. A total of 560 potential LAB isolates were examined, and 87 demonstrated high survival rates in artificial gastrointestinal fluids without hemolytic activity. The selected isolates exhibited significant auto-aggregation (18.35 to 79.42%) and co-aggregation abilities (20.16 to 71.26%). Additionally, the isolates displayed varying degrees of cell surface hydrophobicity (12.32 to 76.24%). Results indicated that 19 LAB isolates had cholesterol assimilation rates exceeding 30%. Moreover, forty strains tested negative for all twelve assessed pathogenic genes and exhibited good adhesion to human intestinal epithelial cells (13.47 to 49.12%). Furthermore, 24 isolates formed strong biofilms, 29 formed moderate biofilms, and 23 formed weak biofilms. Except for isolates ABRIIFBI-8, ABRIIFBI-16, ABRIIFBI-23, ABRIIFBI-43, ABRIIFBI-56, and ABRIIFBI-62, most isolates were capable of producing exopolysaccharides. Consequently, LAB strains naturally occurring in sourdough and traditional dairy samples were suggested as potential probiotic candidates for incorporation into functional foods.

Interpretation of vaginal metagenomic characteristics in different types of vaginitis.

Vaginitis is one of the most common gynecological diseases, mostly caused by infections of pathogens such as Candida albicans and Gardnerella vaginalis. In recent years, it has been found that the stability of the vaginal flora plays an important role in vaginitis. Furthermore, the abundant Lactobacillus-producing rich lactic acid in the vagina provides a healthy acidic environment such as Lactobacillus crispatus. The metabolites of Lactobacillus can inhibit the colonization of pathogens. Here, we collected the vaginal samples of patients with bacterial vaginitis (BV), vulvovaginal candidiasis (VVC), and BV combined with VVC to discover the differences and relationships among the different kinds of vaginitis by metagenomic sequencing. Furthermore, because of the importance of L. crispatus in promoting vaginal health, we isolated multiple strains from vaginal samples of healthy females and chose the most promising strain with potential probiotic benefits to provide clinical implications for treatment strategies.

Poultry Gastrointestinal-derived Lactic Acid Bacteria (pGIT-d-LAB) Inhibit Multiple Antibiotics Resistance Bacterial and Fungal Pathogens.

To develop a probiotic formulation for poultry feed, a few poultry gastrointestinal derived lactic acid bacteria (pGIT-d-LAB) were isolated from chicken intestinal specimens and in vitro experiment was performed to evaluate their efficacy as potential probiotic candidate. A total of 6 strains of LAB: Lactobacillus brevis (L. brevis), Lactobacillus acidophilus (L. acidophilus), Lactobacillus casei (L. casei), Pediococci spp, Lactobacillus fermentum (L. fermentum) and Lactobacillus plantarum (L. plantarum) were isolated and cultured for collection of Cell Free Supernatant (CFS). CFS collected was tested against pathogenic bacterial isolated from chicken feces as well as prevalent fungal pathogens, utilizing agar-well diffusion techniques. A preliminary investigation into the susceptibility of the pathogens to diverse antibiotics and antifungal drugs was conducted. Bacterial pathogens exhibiting resistance to a minimum of three classes of antibiotics were subsequently identified for pGIT-d-LAB CFS screening. The observed results revealed that the CFS derived from the isolates exhibited varying degrees of growth inhibition against different pathogens. Among the tested pGIT-d-LAB isolates, L. acidophilus demonstrated the most prominent zone of inhibition, measuring 18 mm against Klebsiella pneumoniae ZTAC 1233. Notably, Citrobacter diversus ZTAC 1255 showed resistance to all tested pGIT-d-LAB. Quantification of the metabolites produced was performed, and peak production levels was determined. L. acidophilus produced the highest amount of lactic acid (1.789g/l), Pediococci spp. produced the highest amount of diacetyl and H202 (1.918g/l) (0.0025g/l) at 48 hr peak values respectively. The test isolates are potential probiotic candidates for controlling pathogens in poultry.

In vitro safety and functional characterization of the novel Bacillus coagulans strain CGI314.

Bacillus coagulans species have garnered much interest in health-related functional food research owing to their desirable probiotic properties, including pathogen exclusion, antioxidant, antimicrobial, immunomodulatory and food fermentation capabilities coupled with their tolerance of extreme environments (pH, temperature, gastric and bile acid resistance) and stability due to their endosporulation ability. In this study, the novel strain Bacillus coagulans CGI314 was assessed for safety, and functional probiotic attributes including resistance to heat, gastric acid and bile salts, the ability to adhere to intestinal cells, aggregation properties, the ability to suppress the growth of human pathogens, enzymatic profile, antioxidant capacity using biochemical and cell-based methods, cholesterol assimilation, anti-inflammatory activity, and attenuation of hydrogen peroxide (H2O2)-induced disruption of the intestinal-epithelial barrier. B. coagulans CGI314 spores display resistance to high temperatures (40°C, 70°C, and 90°C), and gastric and bile acids [pH 3.0 and bile salt (0.3%)], demonstrating its ability to survive and remain viable under gastrointestinal conditions. Spores and the vegetative form of this strain were able to adhere to a mucous-producing intestinal cell line, demonstrated moderate auto-aggregation properties, and could co-aggregate with potentially pathogenic bacteria. Vegetative cells attenuated LPS-induced pro-inflammatory cytokine gene expression in HT-29 intestinal cell lines and demonstrated broad antagonistic activity toward numerous urinary tract, intestinal, oral, and skin pathogens. Metabolomic profiling demonstrated its ability to synthesize several amino acids, vitamins and short-chain fatty acids from the breakdown of complex molecules or by de novo synthesis. Additionally, B. coagulans CGI314's strong antioxidant capacity was demonstrated using enzyme-based methods and was further supported by its cytoprotective and antioxidant effects in HepG2 and HT-29 cell lines. Furthermore, B. coagulans CGI314 significantly increased the expression of tight junction proteins and partially ameliorated the detrimental effects of H2O2 induced intestinal-epithelial barrier integrity. Taken together these beneficial functional properties provide strong evidence for B. coagulans CGI314 as a promising potential probiotic candidate in food products.

Identification of new yeast strains, Candida zeylanoidesY12‐3 and Hyphopichia pseudoburtoniiY12‐1, from the intestinal tract of rainbow trout, Oncorhynchus mykiss, with potential probiotic characteristics

AbstractIn this study, 2 yeasts, Candida zeylanoides isolate Y12‐3 (MN073455.1) and Hyphopichia pseudoburtonii isolate Y12‐1 (MN073489.1), were isolated from rainbow trout hindguts. Their identity was confirmed by amplification of internal transcribed spacer (ITS) gene regions. Their in vitro probiotic properties showed that they were hydrophobic and did not inhibit bacterial growth. However, they displayed positive co‐aggregation with several bacterial pathogens. It was interesting that Y12‐1 and Y12‐3 isolates survived and grew well in bile salt concentrations ranging from 0.6% to 1.5% and at low pH conditions. After a 35‐day feeding trial, the results of dietary incorporation of the yeast isolates showed that serum myeloperoxidase activity was unchanged in the treated and control groups. Meanwhile, serum lysozyme activity in yeast groups was decreased significantly compared to the control. However, fish fed with Y12‐1 had higher total protein, albumin, and globulin than other groups. Total cholesterol levels were decreased significantly in yeast groups compared to the control. Interestingly, the Y12‐1 and Y12‐3 groups showed higher survival (69.05% and 80.95%) after the challenge with Lactococcus garvieae compared to the control (45.24%). In brief, the aforementioned findings showed that Y12‐1 and Y12‐3 strains could be potential probiotic candidates for use in rainbow trout farming.

Karakterisasi dan Uji Aktivitas Antimikroba Bakteri Kandidat Probiotik dari Terasi Udang Rebon

Probiotics are live microorganisms that are widely used to help maintain a healthy digestive system. Some compounds secreted by these bacteria have a bactericidal effect on pathogenic and putrefactive bacteria. Various types of probiotic bacteria can be obtained from fermented foods and drinks. This research aims to characterize bacteria from rebon shrimp paste in Macajah Village, Tanjung Bumi District, Bangkalan Regency, East Java Province which have potential as probiotics and test their antimicrobial activity against pathogenic bacteria. Bacteria were isolated using the Pour Plate technique using de Man Rogosa Sharpe Agar media. The bacterial isolates were then characterized by observing colony morphology, cells and biochemical properties. Next, antibacterial activity was tested using the well diffusion method. The results showed that the four bacteria obtained from the samples were gram positive, round and rod shaped, catalase negative, homofermentative, grew at a temperature of 37-45°C, survived at NaCl concentrations of 4 and 6.5%, low pH, and bile salts. According to the characterization results, three bacterial isolates belonged to the genus Enterococcus and one other isolate belonged to the genus Bacillus. Bacillus isolate is a potential probiotic candidate, because it has inhibitory activity against Escherichia coli and Staphylococcus aureus.

Probiotic Properties and Anti-inflammatory Activity of Bacillus spp. Isolated from Ethnically Fermented Soybean

Bacillus spp. probiotics used as feed additives can form spores and tolerate the harsh conditions of the human digestive system and are beneficial for the treatment of inflammatory bowel syndrome. Since reports on probiotics and anti-inflammatory properties of Bacillus spp. isolated from the fermented food of Northeast India have not been explored much. The present study focused on Bacillus spp. BN5, AY5, and AN8, possessing these desired properties. In the probiotics study, the isolates were screened for their tolerance to acid and bile salt, auto-aggregation, hydrophobicity, cholesterol assimilation, antibiotic resistance, and antagonistic properties. It was found that these isolates possessed the desirable probiotic traits. The Bacillus spp. culture and their supernatant were also screened for their ability to reduce LPS-induced inflammation in murine macrophage (RAW 264.7) cells. All the Bacillus spp. culture and their supernatant treatments were found to reduced the Nitric oxide (NO) production by LPS-induced cell lines. The supernatant of LPS-induced cell lines were also analyzed to measure the level of inflammatory cytokine production. It was found that the levels of TNF-α, IL-6, and IL-1β were reduced after co-treatment with LPS and Bacillus spp. culture or LPS and Bacillus spp. supernatant. Results suggested that the Bacillus spp. are potential probiotic candidates with anti-inflammatory properties.

Ligilactobacillus salivarius CNCM I-4866, a potential probiotic candidate, shows anti-inflammatory properties in vitro and in vivo

IntroductionThe aim of this work was to characterize a new strain of Ligilactobacillus salivarius (CNCM I-4866) (CNCM I-4866) to address its potential as probiotic with a special focus on intestinal inflammation. Potential anti-inflammatory abilities of this strain were evaluated through in vivo and in vitro experiments.MethodsFirstly, the strain was tested in a murine acute inflammation colitis model induced by DNBS. In vitro characterization was then performed with diverse tests: modulation capability of intestinal permeability; study of the impact on immunity profile through cytokines dosage; capacity to inhibit pathogens and adhere to intestinal cells lines. Production of metabolites, antibiotic resistance and survival to gastro-intestinal tract conditions were also tested.ResultsIn vitro assay has shown a reduction of colonic damage and markers of inflammation after treatment with CNCM I-4866. Transcriptomic analysis performed on colons showed the capacity of the strain to down-regulate pro-inflammatory cytokines. L. salivarius CNCM I-4866 exerted anti-inflammatory profile by reducing IL-8 production by TNF-α stimulated cell and modulated cytokines profile on peripheral blood mononuclear cells (PBMC). It protected intestinal integrity by increasing trans-epithelial electrical resistance (TEER) on Caco-2 TNF-α inflamed cells. Additionally, L. salivarius CNCM I-4866 displayed inhibition capacity on several intestinal pathogens and adhered to eukaryotic cells. Regarding safety and technical concerns, CNCM I-4866 was highly resistant to 0.3% of bile salts and produced mainly L-lactate. Finally, strain genomic characterization allowed us to confirm safety aspect of our strain, with no antibiotic gene resistance found.DiscussionTaken together, these results indicate that L. salivarius CNCM I-4866 could be a good probiotic candidate for intestinal inflammation, especially with its steady anti-inflammatory profile.

Deciphering the probiotic properties and safety assessment of a novel multi-stress-tolerant aromatic yeast Pichia kudriavzevii HJ2 from marine mangroves

With the increasing demand for diversified health, the characteristic probiotics species resources need to be expanded. Here, a novel marine multi-stress-tolerant aromatic yeast Pichia kudriavzevii HJ2 was identified from marine mangrove. Based on the characterization of probiotic properties in vivo and in vitro, the yeast could assimilate multiple carbon sources, and generate volatile flavor metabolites, achieved a 79.98% cholesterol removal rate with efficient in vivo survival and adhesion capabilities, and showed a strong antioxidant capacity. HJ2 also released hydrolase and fermented dietary fiber to yield SCFAs, contributing to disease prevention and treatment. Then, the safety was assessed according to phenotype and whole genome-sequencing analysis. No virulence genes or ARGs were annotated in the HJ2 genome. A few biogenic amines (BA)-related genes were observed, but the production of various BA and total BA were far below the food-defined thresholds. HJ2 did not produce virulence enzymes such as DNase, phospholipase, gelatinase, or coagulase, and exhibited sensitivity to amphotericin B and anidulafungin without β-hemolysis. An in vivo acute toxicity test conducted on mice demonstrated that HJ2 is safe. In conclusion, HJ2 could be considered safe and be further used as a potential probiotic candidate for further clinical trials.

Isolation and screening of lactic acid bacteria producing anti-Edwardsiella from the gastrointestinal tract of wild catfish (Clarias gariepinus) for probiotic candidates

Abstract Introduction Members of lactic acid bacteria (LAB) have been well known for their antimicrobial activities against various bacterial pathogens in aquaculture species. Thus, the present study aimed at isolating LAB members from the intestinal tract of wild-caught catfish, Clarias gariepinus, and screening them for antimicrobial production against one of the most common bacterial pathogens, Edwardsiella ictaluri. Material and methods LAB were isolated from the intestinal tract of wild catfish caught at the Brantas River, East-Java Indonesia. Then, LAB were screened for antimicrobial activity against E. ictaluri by in vitro assays and further assessed for probiotic candidates. Results A total of 29 LAB were successfully isolated and further screened for anti-edwarsiella activities. Of the 29, six isolates had strong anti-edwardsiella activity (diameter of inhibition zone, >10 mm). Based on their 16 s rRNA gene sequences, these LABs were identified as Lactococcus lactis, Enterococcus hirae, Weissella confusa, Weissella cibaria, and Enterococcus faecalis (two isolates). Further in vitro assays indicated that E. faecalis, L. lactis, W. confusa, and W. cibaria had good viability in the intestinal tract condition, having good adhesion capacity to intestinal mucus, and being harmless to catfish. However, two species (E. faecalis and W. cibaria) were resistant to novobiocin and enrofloxacin, respectively. Conclusion Three LAB species (E. faecalis, L. lactis, and W. confusa) are potential probiotic candidates in aquaculture to prevent enteric septicemia of catfish disease. However, further studies are needed to evaluate the use of probiotics in vivo.

Probiotic potential of gluten degrading Bacillus tequilensis AJG23 isolated from Indian traditional cereal-fermented foods as determined by Multiple Attribute Decision-Making analysis

The present study reported the characterization of gluten hydrolyzing strains of Bacillus sp. from fermented cereal dough. The strains were characterized for probiotic as well as technological attributes. A total of 45 presumptive gluten degrading isolates were obtained on gliadin agar plate assay. Based on hemolytic and antibiotic susceptibility pattern, only six isolates were considered safe which also indicated gliadinase activity on zymography. All the six strains were able to resist the pH 2.0, 0.25% bile and also possessed ability to adhere to the organic solvents and mucin. The cell free supernatant of five strains exhibited antimicrobial activities against Gram-positive and Gram-negative pathogens. A more than 50% survival of the isolated strains was obtained at a salt concentration of 2%, phenol concentration of 0.1% and temperature upto 45 °C. All the strains exhibited antioxidant activities and biofilm forming ability. Furthermore, the ranking of strains based on probiotic as well as other functional attributes was determined using multidimensional Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). A matrix of multidimensional indicators was prepared using alternatives and criteria, the analysis indicated the strain Bacillus tequilensis AJG23 as the potential probiotic candidate based on all screening criteria. Further work still needs to be done about the protective role of the potential strain against gluten sensitivity using in vitro models.

Molecular Assessment and Validation of the Selected Enterococcal Strains as Probiotics.

Probiotics are live microorganisms which confer health benefits to the host. Lactic acid bacteria (LAB) are used as probiotics since decades. Enterococci being the member of LAB have proven probiotic strains; therefore, this study was aimed at finding out the potential probiotic candidates from the pool of locally isolated strains. For initial screening, one hundred and twenty-two strains were selected and subjected to different confirmatory and phenotypic tests to choose the best strains that have potential probiotic criteria, i.e., no potential virulence traits, antibiotic resistance, and having tolerance properties. Keeping this criterion, only eleven strains (n = 11) were selected for further assessment. All virulence traits such as production of hemolysin, gelatinase, biofilm, and DNase were performed and not found in the tested strains. The molecular assessment indicates the presence of few virulence-associated genes in Enterococcus faecalis strains with variable frequency. The phenotypic and genotypic assessments of antibiotic resistance profile indicate that the selected strain was susceptible to ten commonly used antibiotics, and there were no transferrable antibiotic resistance genes. The presence of CRISPR-Cas genes also confirmed the absence of antibiotic resistance genes. Various enterocin-producing genes like EntP, EntB, EntA, and EntQ were also identified in the selected strains which make them promising probiotic lead strains. Different tolerance assays like acid, NaCl, and gastric juice tolerance that mimic host conditions was also evaluated by providing artificial conditions. Cellular adhesion and aggregation properties like auto- and co-aggregation were also checked and their results reflect all in the favor of lead probiotic strains.

Utilizing dietary probiotics can boost amberjack (Seriola dumerili) lysozyme activity, antioxidant capacity, and gut microbiota

In aquaculture, natural and eco-friendly resources are prioritized over synthetic inputs (e.g., antibiotics), and optimizing sustainable production methods is necessary. Probiotics have been well known for various potential functions in animal performance and health when supplemented as a single or mix of strain (s) in the diet. Consuming the right probiotic blend (synergistic types) is more advantageous than using each kind individually due to combining each species' functions. The present trial aimed to examine the potential impacts of two probiotic mixtures on the performance and well-being of amberjack juveniles (5.63 ± 0.04 g; Number = 300) for a 60-day feed trial. Three experimental diets (43.5 ± 0.50% total protein and 12.55 ± 0.17% total lipid) were formulated with no probiotics supplement for the control (CD1) or with probiotics mixture supplement. Probiotic mixtures were supplemented at 2 g/kg diet for groups D2 [Bacillus amyloliquefaciens TOA5001 (BA) + Streptococcus faecalis T-110 (SF)] and D3 [Bacillus amyloliquefaciens, Streptococcus faecalis T-110, Lactobacillus plantarum TO-A, Bacillus mesentericus TO-A] respectively. The analysis revealed no difference in all means of growth parameters, feed utilization, survival rate, biometric indices, whole-body composition, and blood parameters between control and probiotic-supplemented diet groups. Liver lysozyme activity, superoxide dismutase, peroxidase activity, and biological antioxidant (BAP) were significantly improved in fish fed D2 compared to CD1 (P < 0.05). The higher (P < 0.05) content of intestinal lactic acid bacteria was noted in fish group fed diet D2, with an improved intestinal histological structure such as increased villi length, cryptal depth, and goblet cells compared to those provided with CD1 and D3 diets. In conclusion, incorporating a mix of probiotic bacteria [BA+SF] at a 2 g/kg diet has remarkable effects on intestinal health, immune responses, and oxidative status of amberjack, S. dumerili, suggesting a potential probiotic candidate for this species.

Probiotic Yeasts and How to Find Them-Polish Wines of Spontaneous Fermentation as Source for Potentially Probiotic Yeasts.

One approach towards maintaining healthy microbiota in the human gastrointestinal tract is through the consumption of probiotics. Until now, the majority of probiotic research has focused on probiotic bacteria, but over the last few years more and more studies have demonstrated the probiotic properties of yeast, and also of species besides the well-studied Saccharomyces cerevisiae var. boulardii. Probiotic strains have to present the ability to survive in harsh conditions of the host body, like the digestive tract. Must fermentation might be an example of a similar harsh environment. In the presented study, we examined the probiotic potential of 44 yeast strains isolated from Polish wines. The tested isolates belonged to six species: Hanseniaspora uvarum, Pichia kluyveri, Metschnikowia pulcherrima, Metschnikowia ziziphicola, Saccharomyces cerevisiae and Starmerella bacillaris. The tested strains were subjected to an assessment of probiotic properties, their safety and their other properties, such as enzymatic activity or antioxidant properties, in order to assess their potential usefulness as probiotic yeast candidates. Within the most promising strains were representatives of three species: H. uvarum, M. pulcherrima and S. cerevisiae. H. uvarum strains 15 and 16, as well as S. cerevisiae strain 37, showed, among other features, survivability in gastrointestinal tract conditions exceeding 100%, high hydrophobicity and autoaggregation, had no hemolytic activity and did not produce biogenic amines. The obtained results show that Polish wines might be a source of potential probiotic yeast candidates with perspectives for further research.