Adhesion and aggregation ability of probiotic strain Lactobacillus acidophilus M92

Encapsulated probiotic Lactiplantibacillus strains with promising applications as feed additives for broiler chickens

Lactic acid bacteria (LAB), particularly Lactobacilli strains, represent a widely studied and promising group of probiotics with numerous potential health benefits. In this study, we isolated LAB strains from fecal samples of healthy broiler chickens and characterized their probiotic properties. Out of 62 initial isolates, five strains were selected for further investigations based on their antibacterial activity against pathogenic bacteria. These selected strains were identified as Lactiplantibacillus species. They exhibited desirable probiotic traits, including non-hemolyis, non-cytotoxicity, lack of antibiotic resistance, acid tolerance, auto-aggregation, and antioxidative potential. Encapsulation of these strains in alginate beads enhanced their survival compared to free cells, in stomach (69-87 % vs. 34-47 %) and intestinal (72-100 % vs. 27-51 %) juices, after 120 min exposure. These findings suggest that encapsulated Lactiplantibacillus strains could be used as feed additives for broiler chickens. Nevertheless, further studies are needed to set on their probiotic potential in vivo.

Screening Probiotics for Anti-Helicobacter pylori and Investigating the Effect of Probiotics on Patients with Helicobacter pylori Infection

Probiotics are natural microbial agents with beneficial properties such as bacteriostatic and anti-infective properties. Lactobacillus plantarum Q21, Q25 and QA85, were isolated from the Chinese specialty fermented food "Jiangshui" and proved to be highly resistant to Helicobacter pylori (p < 0.0001). In vitro results showed that Q21, Q25 and QA85 strongly inhibited H. pylori and could specifically co-aggregate H. pylori in vitro (more than 56%). Strains have the potential to adhere to cells and hinder H. pylori colonization (p < 0.0001). To assess the anti-H. pylori efficacy of strains in vivo, volunteers were recruited and a self-controlled study of probiotic intervention was conducted. Compared to pre-probiotics, volunteers who took Q21, Q25 and QA85 for 1 month showed significant improvement in discomfort, a significant reduction in GSRS scores (p < 0.05), and modulation of inflammatory response (p < 0.05). Q21, Q25 and QA85 resulted in a decreasing trend of H. pylori load in volunteers (454.30 ± 327.00 vs. 328.35 ± 237.19, p = 0.06). However, the strains were not significantly effective in modulating the imbalance of the gut microbiota caused by H. pylori infection. In addition, strains affect metabolic pathways by increasing the levels of O-Phosphoethanolamine and other related metabolites, which may ameliorate associated symptoms. Therefore, Lactobacillus plantarum Q21, Q25 and QA85 can be regarded as a candidate probiotic preparation that exerts direct or indirect anti-H. pylori effects by inhibiting H. pylori activity and colonization, reducing inflammation and discomfort, maintaining homeostasis in the internal environment, affecting the metabolic pathways and repairing the body barrier. They can play a role in relieving H. pylori infection.

Putative Probiotic Ligilactobacillus salivarius Strains Isolated from the Intestines of Meat-Type Pigeon Squabs

This study aims to screen for potential probiotic lactic acid bacteria from the intestines of meat-type pigeon squabs. Ligilactobacillus salivarius YZU37 was identified as the best comprehensive performed strain. Being acid- and bile salt-tolerant, it displayed growth-inhibition activities against Staphylococcus aureus ATCC25923, Escherichia coli ATCC25922, and Salmonella typhimurium SL1344, exhibited sensitivity to 6 commonly used antibiotics, and endowed with good cell surface hydrophobicity, auto-aggregation property, and anti-oxidant activities. Results of in vitro experiments indicated that the bacteriostatic effects of this strain were related to the production of proteinaceous substances that depend on acidic conditions. Whole-genome sequencing of L. salivarius YZU37 was performed to elucidate the genetic basis underlying its probiotic potential. Pangenome analysis of L. salivarius YZU37 and other 212 L. salivarius strains available on NCBI database revealed a pigeon-unique gene coding choloylglycine hydrolase (CGH), which had higher enzyme-substrate binding affinity than that of the common CGH shared by L. salivarius strains of other sources. Annotation of the functional genes in the genome of L. salivarius YZU37 revealed genes involved in responses to acid, bile salt, heat, cold, heavy metal, and oxidative stresses. The whole genome analysis also revealed the absence of virulence and toxin genes and the presence of 65 genes distributed under 4 CAZymes classes, 2 CRISPR-cas regions, and 3 enterolysin A clusters which may confer the acid-dependent antimicrobial potential of L. salivarius YZU37. Altogether, our results highlighted the probiotic potential of L. salivarius YZU37. Further in vivo investigations are required to elucidate its beneficial effects on pigeons.

The Application of Probiotic Bacteria from Strawberry (Fragaria ananassa × Duch.) in the Fermentation of Strawberry Tree Fruit (Arbutus unedo L.) Extract

The search for unexplored plant resources that would provide a good basis for the development of novel probiotic functional foods is rapidly increasing. In this context, the strawberry tree fruit (Arbutus unedo L.) is particularly interesting, as it is rich in numerous antioxidant bioactive compounds that have been shown to be beneficial to health, but have not yet found industrial applications. In this work, the probiotic characterization of lactic acid bacteria strain Lactiplantibacillus plantarum DB2, isolated from strawberries (Fragaria ananassa × Duch.), was performed. The tested strain proved to be safe to use, displaying no antibiotic resistance or hemolytic activity. Due to its proven probiotic potential during simulated gastrointestinal transit, its antimicrobial activity, and its coaggregation with pathogens, it was selected for fermentation of an aqueous Arbutus unedo L. extract, which was subsequently microencapsulated and freeze-dried to extend its shelf life and preserve its functional properties. The antioxidant activity of the ferment obtained was maintained (80%), while after microencapsulation and freeze-drying, about 50% and 20% of the antioxidant activity was retained, respectively. In conclusion, this study demonstrates for the first time the application of probiotics isolated from strawberries in the fermentation of strawberry tree extract and monitors the antioxidant activity during post-fermentation formulation, paving the way for a potential industrial application of this underutilized plant.

Woodfordia fruticosa fermented with lactic acid bacteria impact on foodborne pathogens adhesion and cytokine production in HT-29 cells

Introduction

The study into the interplay between foodborne pathogens and human health, particularly their effects on intestinal cells, is crucial. The importance of lactic acid bacteria (LAB) in promoting a healthy balance of gut microbiota, inhibiting harmful bacteria, and supporting overall gastrointestinal health is becoming more apparent.

Methods

Our study delved into the impact of fermenting Woodfordia fruticosa (WF), a plant known for its antimicrobial properties against gastrointestinal pathogens, with LAB. We focused on the influence of this fermentation process on the binding of foodborne pathogens to the gut lining and cytokine production, aiming to enhance gut health and control foodborne infections in HT-29 cells.

Results and discussion

Post-fermentation, the WF exhibited improved antimicrobial effects when combined with different LAB strains. Remarkably, the LAB-fermented WF (WFLC) substantially decreased the attachment of pathogens such as L. monocytogenes (6.87%  ±  0.33%) and V. parahaemolyticus (6.07%  ±  0.50%) in comparison to the unfermented control. Furthermore, WFLC was found to upregulate IL-6 production in the presence of pathogens like E. coli O157:H7 (10.6%) and L. monocytogenes (19%), suggesting it may activate immune responses. Thus, LAB-fermented WF emerges as a potential novel strategy for fighting foodborne pathogens, although additional studies are warranted to thoroughly elucidate WF's phytochemical profile and its contribution to these beneficial outcomes.

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

BACKGROUND

The 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.

RESULTS

The 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.

CONCLUSION

This 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.

Effects of p-coumaric acid on probiotic properties of Lactobacillus acidophilus LA-5 and lacticaseibacillus rhamnosus GG

Probiotics are defined as "live microorganisms that provide health benefits to the host when administered in adequate amounts." Probiotics have beneficial effects on human health, including antibacterial activity against intestinal pathogens, regulation of blood cholesterol levels, reduction of colitis and inflammation incidence, regulation of the immune system, and prevention of colon cancer. In addition to probiotic bacteria, some phenolic compounds found in foods we consume (both food and beverages) have positive effects on human health. p-coumaric acid (p-CA) is one of the most abundant phenolic compounds in nature and human diet. The interactions between these two different food components (phenolics and probiotics), resulting in more beneficial combinations called synbiotics, are not well understood in terms of how they will affect the gut microbiota by promoting the probiotic properties and growth of probiotic bacteria. Thus, this study aimed to investigate synbiotic relationship between p-CA and Lactobacillus acidophilus LA-5 (LA-5), Lacticaseibacillus rhamnosus GG (LGG). Probiotic bacteria were grown in the presence of p-CA at different concentrations, and the effects of p-CA on probiotic properties, as well as its in vitro effects on AChE and BChE activities, were investigated. Additionally, Surface analysis was conducted using FTIR. The results showed that treatment with p-CA at different concentrations did not exhibit any inhibitory effect on the growth kinetics of LA-5 and LGG probiotic bacteria. Additionally, both probiotic bacteria demonstrated high levels of antibacterial properties. It showed that it increased the auto-aggregation of both probiotics. While p-CA increased co-aggregation of LA-5 and LGG against Escherichia coli, it decreased co-aggregation against Staphylococcus aureus. Probiotics grown with p-CA were more resistant to pepsin. While p-CA increased the resistance of LA-5 to bile salt, it decreased the resistance of LGG. The combinations of bacteria and p-CA efficiently suppressed AChE and BChE with inhibition (%) 11.04-68.43 and 13.20-65.72, respectively. Furthermore, surface analysis was conducted using FTIR to investigate the interaction of p-coumaric acid with LA-5 and LGG, and changes in cell components on the bacterial surface were analyzed. The results, recorded in range of 4000 -600 cm-1 with resolution of 4 cm-1, demonstrated that p-CA significantly affected only the phosphate/CH ratio for both bacteria. These results indicate the addition of p-CA to the probiotic growth may enhance the probiotic properties of bacteria.

Geroprotective Effect of Levilactobacillus brevis and Weizmannia coagulans in Caenorhabditis elegans

The prophylactic use of lactic acid bacteria (LAB) to maintain human health is one of the most important research areas in recent times. LAB supplementation confers a wide range of health benefits to the host, but few studies have focused on their possible role in delaying the aging process. This study explored the health and life-promoting properties of two LAB, Levilactobacillus brevis and Weizmannia coagulans, using the Caenorhabditis elegans model. We found that L. brevis and W. coagulans enhanced the intestinal integrity and intestinal barrier functions without affecting the overall physiological functions of C. elegans. Wild-type worms preconditioned with LAB strains increased their survival under oxidative and thermal stress conditions by reducing intracellular reactive oxygen levels. Live L. brevis and W. coagulans significantly extended the lifespan of C. elegans under standard laboratory conditions independently of dietary restrictions. Genetic and reporter gene expression analysis revealed that L. brevis and W. coagulans extend lifespan via insulin/insulin-like growth factor-1 signaling and the p38 MAPK signaling axis. Furthermore, sirtuin, JNK MAPK, and mitochondrial respiratory complexes were found to be partially involved in W. coagulans-mediated lifespan extension and stress resilience. Preconditioning with LAB ameliorated age-related functional decline in C. elegans and reduced ectopic fat deposition in an NHR-49-dependent manner. Together, our findings indicated that L. brevis and W. coagulans are worth exploring further as "gerobiotic" candidates to delay aging and improve the healthspan of the host.

Therapeutic Potential of Bacteroides fragilis SNBF-1 as a Next-Generation Probiotic: In Vitro Efficacy in Lipid and Carbohydrate Metabolism and Antioxidant Activity

This study explores the potential of aerotolerant Bacteroides fragilis (B. fragilis) strains as next-generation probiotics (NGPs), focusing on their adaptability in the gastrointestinal environment, safety profile, and probiotic functions. From 23 healthy infant fecal samples, we successfully isolated 56 beneficial B. fragilis strains. Notably, the SNBF-1 strain demonstrated superior cholesterol removal efficiency in HepG2 cells, outshining all other strains by achieving a remarkable reduction in cholesterol by 55.38 ± 2.26%. Comprehensive genotype and phenotype analyses were conducted, including sugar utilization and antibiotic sensitivity tests, leading to the development of an optimized growth medium for SNBF-1. SNBF-1 also demonstrated robust and consistent antioxidant activity, particularly in cell-free extracts, as evidenced by an average oxygen radical absorbance capacity value of 1.061 and a 2,2-diphenyl-1-picrylhydrazyl scavenging ability of 94.53 ± 7.31%. The regulation of carbohydrate metabolism by SNBF-1 was assessed in the insulin-resistant HepG2 cell line. In enzyme inhibition assays, SNBF-1 showed significant α-amylase and α-glucosidase inhibition, with rates of 87.04 ± 2.03% and 37.82 ± 1.36%, respectively. Furthermore, the cell-free supernatant (CFS) of SNBF-1 enhanced glucose consumption and glycogen synthesis in insulin-resistant HepG2 cells, indicating improved cellular energy metabolism. This was consistent with the observation that the CFS of SNBF-1 increased the proliferation of HepG2 cells by 123.77 ± 0.82% compared to that of the control. Overall, this research significantly enhances our understanding of NGPs and their potential therapeutic applications in modulating the gut microbiome.

Probiotic potential and wound-healing activity of Pediococcus pentosaceus strain AF2 isolated from Herniaria glabra L. which is traditionally used to make yogurt

Probiotics have been a part of our lives for centuries, primarily through fermented foods. They find applications in various fields such as food, healthcare, and agriculture. Nowadays, their utilization is expanding, highlighting the importance of discovering new bacterial strains with probiotic properties suitable for diverse applications. In this study, our aim was to isolate new probiotic bacteria. Herniaria glabra L., a plant traditionally used for yogurt making in some regions and recognized in official medicine in many countries, was chosen as the source for obtaining probiotic bacteria. We conducted bacterial isolation from the plant, molecularly identified the isolated bacteria using 16S rRNA sequencing, characterized their probiotic properties, and assessed their wound-healing effects. As a result of these studies, we identified the bacterium isolated from the plant as Pediococcus pentosaceus strain AF2. We found that the strain AF2 exhibited high resistance to conditions within the gastrointestinal tract. Our reliability analysis showed that the isolate had γ-hemolytic activity and displayed sensitivity to certain tested antibiotics. At the same time, AF2 did not show gelatinase and DNase activity. We observed that the strain AF2 produced metabolites with inhibitory activity against E. coli, B. subtilis, P. vulgaris, S. typhimurium, P. aeruginosa, K. pneumoniae, E. cloacae, and Y. pseudotuberculosis. The auto-aggregation value of the strain AF2 was calculated at 73.44%. Coaggregation values against E. coli and L. monocytogenes bacteria were determined to be 56.8% and 57.38%, respectively. Finally, we tested the wound-healing effect of the strain AF2 with cell culture studies and found that the strain AF2 promoted wound healing.

The rumen-derived Lact. mucosae LLK-XR1 exhibited greater free gossypol degradation capacity during solid-state fermentation of cottonseed meal and probiotic potential

BACKGROUND

This study aimed to isolate the rumen-derived bacteria with the ability to degrade free gossypol (FG), and to evaluate the probiotic potential in vitro for ensuring safe utilization.

METHODS

The strains were anaerobically isolated from fresh rumen fluid of sheep with long-term fed cottonseed meal (CSM) with the screening agar medium containing gossypol as the sole carbon source. Afterwards, the isolated strain incubated with CSM was subjected to the determination of the FG degradation and in vitro evaluation of probiotic characteristics.

RESULTS

The target strain labeled Lact. mucosae LLK-XR1 [Accession number: OQ652016.1] was obtained, and its growth on MRS Liquid medium exhibited degradation efficiency of FG up to 69.5% which was significantly greater than its growth on Man-Rogosa-Sharpe medium with glucose free for 24 h (p < 0.01). Meanwhile, LLK-XR1 showed 40.652% degradation rate of FG for unautoclaved, non-pulverized, and no additional nutrients supplementation CSM. Furthermore, LLK-XR1 presented good survivability at pH 3.0 (above 88.6%), and 0.3% bile (78.5%). LLK-XR1 showed sensitivity to broad-spectrum antibiotics except Sulfamethoxazole, Ciprofloxacin and Gentamycin and significantly inhibited E. coli CICC 10,899, Staph. aureus CICC 21,600, and Salmonella. Typhimurium CICC 21,483. LLK-XR1 demonstrated good cell surface hydrophobicity and auto-aggregation ability.

CONCLUSIONS

Taken together, this study for the first time noted that rumen-originated Lact. mucosae LLK-XR1 with probiotic properties exhibited substantial FG degradation capacity when it was applied to the solid-state fermentation of CSM.

Potential of γ-Aminobutyric Acid-Producing Leuconostoc mesenteroides Strains Isolated from Kimchi as a Starter for High-γ-Aminobutyric Acid Kimchi Fermentation

γ-Aminobutyric acid (GABA)-producing Leuconostoc mesenteroides K1501 and K1627, isolated from kimchi, exhibited the highest GABA production in 1% monosodium glutamic acid. Both strains showed high survival rates of approximately 87% in artificial gastric juice (pH 3.0) and >80% in 0.1% artificial bile salt fluid. The survival rate was approximately 28% in 0.3% artificial bile salt fluid and 0% in 0.5% artificial bile salts. Both strains showed excellent adhesion to intestinal epithelial cells (>99%). Furthermore, it was observed that growth was not inhibited at 2% salt concentration; however, it was slightly retarded at salt concentrations of 3% and 4%. Moreover, L. mesenteroides K1501 and K1627 inhibited the growth of certain species of Lactobacillus, whose presence in kimchi fermentation is undesirable. Therefore, L. mesenteroides K1501 and K1627 have the potential to be used as starter organisms for functional GABA-rich kimchi.

Multifunctional properties of the transmembrane LPxTG-motif protein derived from Limosilactobacillus reuteri SH-23

The LPxTG-motif protein is an important transmembrane protein with high hydrophilicity and stability, as evidenced by its stress tolerance and adhesion ability. In this study, a novel LPxTG-motif protein with esterase activity (LEP) was expressed, and the multifunctional properties such as adhesion properties and esterase activity were also investigated. When cocultured with Limosilactobacillus reuteri SH-23, the adhesion ability of L. reuteri SH-23 to HT-29 cells was improved, and this adhesion was further found relating to the potential target protein Pyruvate kinase M1/2 (PKM) of HT-29 cells. In addition, as a multifunctional protein, LEP can promote the hydrolysis of bovine milk lipids with its esterase activity, and the activity was enhanced in the presence of Zn2+ and Mn2+ at pH 7. Furthermore, the polyunsaturated fatty acids (PUFA) such as linoleic acid and eicosapentaenoic acid were found to increase during the hydrolyzing process. These unique properties of LEP provide a comprehensive understanding of the adhesion function and PUFA releasing properties of the multifunctional protein derived from L. reuteri SH-23 and shed light on the beneficial effect of this Lactobacillus strain on the colonization of the gastrointestinal tract.

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.

Effects and Mechanisms of Resveratrol on the Adhesion of Lactobacillus acidophilus NCFM

Based on the adhesion and surface properties of Lactobacillus acidophilus NCFM, five common polyphenols in fruits and vegetables, including resveratrol, epicatechin, quercetin, hesperidin, and caffeic acid, were screened, and the reasons for resveratrol promoting adhesion were systematically explained. The results showed that resveratrol could significantly enhance NCFM adhesion to mucin (1.73 fold), followed by epicatechin (1.47 fold), caffeic acid (1.30 fold), and hesperidin (0.99 fold), while quercetin had a certain degree of inhibition (0.84 fold). The effects of these polyphenols on surface hydrophobicity and auto-aggregation of NCFM were consistent with adhesion results. Then, how resveratrol promotes NCFM adhesion was further explored. The results of the proteomic analysis showed that resveratrol changed the surface layer proteins of NCFM, involving 4 up-regulated proteins and 12 down-regulated proteins. In addition, resveratrol promoted the expression of mucin genes and the glycosylation of mucins on the HT-29 cell surface. Our results indicate that resveratrol changes the surface layer proteins of NCFM to modify surface properties and adhere to mucins. Meanwhile, resveratrol promotes expression and glycosylation of mucins in HT-29 cells. Our findings provide theoretical support for an in-depth explanation of the interaction among resveratrol, NCFM, and the HT-29 cells.

Genomic and phenotypic-based safety assessment and probiotic properties of Streptococcus thermophilus FUA329, a urolithin A-producing bacterium of human milk origin

Streptococcus thermophilus FUA329, a urolithin A-producing bacterium, is isolated from human breast milk. The complete genome sequence of FUA329 did not contain any plasmids and at least 20 proteins were related to extreme environment resistance. Phenotypic assay results demonstrated that FUA329 was susceptible to 12 kinds of antibiotics and did not exhibit any hemolytic or nitrate reductase activity. Three free radical scavenging assays revealed that FUA329 have high antioxidant capability. FUA329 exhibited a cell surface hydrophobicity of 52.58 ± 1.17% and an auto-aggregation rate of 18.69 ± 2.48%. Moreover, FUA329 demonstrated a survival rate of over 60% in strong acid and bile salt environments, indicating that FUA329 may be stable colonization in the gastrointestinal tract. Additionally, we firstly found 3 potential proteins and 11 potential genes of transforming ellagic acid to urolithins in FUA329 genome. The above results indicate that FUA329 has credible safety and probiotic properties, as well as the potential to be developed as a new generation of urolithin A-producing probiotics.

Identification of four autochthonous yeasts from the intestines of goldfish, Carassius auratus with potential probiotic properties and their effects on the most common fish bacterial pathogens

In aquaculture, probiotic yeasts have gained particular interest because of their numerous health benefits for farmed fish. Many autochthonous yeasts have been isolated and identified from fish species with potential probiotic characteristics. In the present study, four autochthonous yeast strains were identified and characterized from the intestinal tracts of 16 healthy goldfish, Carassius auratus. Their in vitro probiotic properties were examined in terms of cell surface hydrophobicity, co-aggregation, and tolerability to different pH values and bile salt concentrations. These strains were identified by culture characters and sequence analysis of ITS (Internal Transcribed Spacer) gene regions. Four strains, namely Cutaneotrichosporon jirovecii isolate jpn01, Debaryomyces nepalensis isolate jpn02, Blastobotrys proliferans isolate jpn05, and Diutina catenulata isolate jpn06, were identified and added to the NCBI GenBank with accession numbers defined as MT584874.1, MT584873.1, MT649918.1, and MT501155.1, respectively. Results demonstrated the capability of these strains to co-aggregate with several fish-associated bacterial pathogens such as Lactococcus garvieae, Vagococcus salmoninarum, Vibrio anguillarum, Yersinia ruckeri, and Aeromonas hydrophila. Only the jpn05 strain did not co-aggregate with A. hydrophila. All identified yeast isolates could grow and tolerate low pH conditions (pH 2.0) and bile salt concentrations (up to 1.5%). Of interest, the hydrophobicity (%) of the yeast isolates was 80%, 94.0%, 80.6%, and 66.4% for jpn01, jpn02, jpn05, and jpn06 isolates, respectively. In this context, our data provide important in vitro evidence for the potential probiotic features of the yeast isolates. These strains could be considered candidate probiotic yeasts; however, their application in aquaculture nutrition necessitates further in vivo assays.

The Effect of Maternal Probiotic or Synbiotic Supplementation on Sow and Offspring Gastrointestinal Microbiota, Health, and Performance

The increasing prevalence of antimicrobial-resistant pathogens has prompted the reduction in antibiotic and antimicrobial use in commercial pig production. This has led to increased research efforts to identify alternative dietary interventions to support the health and development of the pig. The crucial role of the GIT microbiota in animal health and performance is becoming increasingly evident. Hence, promoting an improved GIT microbiota, particularly the pioneer microbiota in the young pig, is a fundamental focus. Recent research has indicated that the sow's GIT microbiota is a significant contributor to the development of the offspring's microbiota. Thus, dietary manipulation of the sow's microbiota with probiotics or synbiotics, before farrowing and during lactation, is a compelling area of exploration. This review aims to identify the potential health benefits of maternal probiotic or synbiotic supplementation to both the sow and her offspring and to explore their possible modes of action. Finally, the results of maternal sow probiotic and synbiotic supplementation studies are collated and summarized. Maternal probiotic or synbiotic supplementation offers an effective strategy to modulate the sow's microbiota and thereby enhance the formation of a health-promoting pioneer microbiota in the offspring. In addition, this strategy can potentially reduce oxidative stress and inflammation in the sow and her offspring, enhance the immune potential of the milk, the immune system development in the offspring, and the sow's feed intake during lactation. Although many studies have used probiotics in the maternal sow diet, the most effective probiotic or probiotic blends remain unclear. To this extent, further direct comparative investigations using different probiotics are warranted to advance the current understanding in this area. Moreover, the number of investigations supplementing synbiotics in the maternal sow diet is limited and is an area where further exploration is warranted.

Latilactobacillus curvatus FFZZH5L isolated from pickled cowpea enhanced antioxidant activity in Caenorhabditis elegans by upregulating the level of glutathione S-transferase

Latilactobacillus curvatus is a potential probiotic that possesses beneficial health properties and fermentation traits; however, the extent of understanding of the antioxidant activities of L. curvatus is limited. This study investigates the antioxidant activities of a new L. curvatus FFZZH5L strain. The strain exhibits broad tolerance to acids, bases and salts and demonstrated good adaption to the gastrointestinal environment, with a survival rate of 45% after 24 h of treatment in artificial gastrointestinal juice. Moreover, L. curvatus FFZZH5L exhibits inhibitory effects on Staphylococcus aureus, with a self-aggregation rate of 34.8% and a co-aggregation rate of 82.2%. In vitro, the DPPH radical scavenging ability and GSH-px enzyme activity of L. curvatus FFZZH5L reach 64.27% and 15.95 U mL-1, respectively. Treatment of C. elegans with L. curvatus FFZZH5L in vivo significantly extended the organism's lifespan. Furthermore, the activity of SOD, GSH-px and T-AOC was increased by 33.6%, 43.4% and 58.3%, respectively. Feeding C. elegans with L. curvatus FFZZH5L decreased the MDA, lipofuscin and ROS levels by 9%-36.4%. L. curvatus FFZZH5L effectively protected C. elegans against juglone-induced oxidative stress damage and led to a significant increase in the organism's survival under heat stress. The RT-qPCR analysis suggests that feeding C. elegans with L. curvatus FFZZH5L upregulates the expression levels of antioxidant-related genes including glutathione S-transferase 4 (gst-4), gst-1, gst-10, sod-3, sod-5, and sod-10 in C. elegans. Our investigation confirms the probiotic and antioxidant properties of L. curvatus, indicating its potential application in functional foods and the pharmaceutical industry.

Assessment of beneficial effects and identification of host adaptation-associated genes of Ligilactobacillus salivarius isolated from badgers

BACKGROUND

Ligilactobacillus salivarius has been frequently isolated from the gut microbiota of humans and domesticated animals and has been studied as a candidate probiotic. Badger (Meles meles) is known as a "generalist" species that consumes complex foods and exhibits tolerance and resistance to certain pathogens, which can be partly attributed to the beneficial microbes such as L. salivarius in the gut microbiota. However, our understanding of the beneficial traits and genomic features of badger-originated L. salivarius remains elusive.

RESULTS

In this study, nine L. salivarius strains were isolated from wild badgers' feces, one of which exhibited good probiotic properties. Complete genomes of the nine L. salivarius strains were generated, and comparative genomic analysis was performed with the publicly available complete genomes of L. salivarius obtained from humans and domesticated animals. The strains originating from badgers harbored a larger genome, a higher number of protein-coding sequences, and functionally annotated genes than those originating from humans and chickens. The pan-genome phylogenetic tree demonstrated that the strains originating from badgers formed a separate clade, and totally 412 gene families (12.6% of the total gene families in the pan-genome) were identified as genes gained by the last common ancestor of the badger group. The badger group harbored significantly more gene families responsible for the degradation of complex carbohydrate substrates and production of polysaccharides than strains from other hosts; many of these were acquired by gene gain events.

CONCLUSIONS

A candidate probiotic and nine L. salivarius complete genomes were obtained from the badgers' gut microbiome, and several beneficial genes were identified to be specifically present in the badger-originated strains that were gained in the evolution. Our study provides novel insights into the adaptation of L. salivarius to the intestinal habitat of wild badgers and provides valuable strain and genome resources for the development of L. salivarius as a probiotic.

Weissella confusa N17 Derived from Loach (Misgurnus anguillicaudatus) Exhibits Promising for Further Applications in Loach Aquaculture

The application of probiotics, in aquaculture, is becoming increasingly widespread and have had positive application effects. However, reports of loach-derived probiotics are quite limited. In this study, two representative strains of lactic acid bacteria with excellent traits, namely, Weissella confusa N17 and Lactobacillus saniviri N19, were screened from the intestine of healthy loaches. W. confusa N17 and L. saniviri N19 could inhibit different common various pathogenic bacteria, especially Aeromonas spp., and were sensitive to the most common antibiotics. The survival rate of the two strains exceeded 50% after 4 h of incubation in 10% loach bile. Moreover, the two strains showed significant tolerance to trypsin. Their autoaggregation capacity and hydrophobicity were greater than 30%. In addition, the aggregation ability of both strains was higher than 30% for both A. veronii TH0426 and A. hydrophila TPS. The two strains had a high biofilm-forming ability and strong adhesion to epithelioma papulosum cyprini (EPC) cells. Scanning electron microscopy results showed that the culture supernatants of the two strains had a significantly destructive effect on A. veronii TH0426 and A. hydrophila TPS. Overall, the traits of W. confusa N17 were better than those of L. saniviri N19. Genome sequencing and analysis demonstrated a lack of virulence factor-related or drug resistance-related genes in genome N17. The diet supplemented with the W. confusa N17 strain significantly improved the resistance of loaches to A. veronii infection, and the protection rate reached 57.1%. Therefore, W. confusa N17 exhibits promising for further applications in loach aquaculture.

Co-cultivation effects of Lactobacillus helveticus SNA12 and Kluveromyces marxiensis GY1 on the probiotic properties, flavor, and digestion in fermented milk

This study aimed to evaluate inoculating the lactic acid bacteria Lactobacillus helveticus SNA12 and the yeast Kluyveromyces marxiensis GY1 as starter cultures on milk fermentation. In this study, the probiotic properties of L. helveticus SNA12, K. marxiensis GY1 and co-culture of these two strains (L. helveticus SNA12-K. marxiensis GY1) were investigated, and the results showed that K. marxiensis GY1 had better gastrointestinal tolerance, aggregation, and cell adhesion properties than L. helveticus SNA12. After the co-cultivation of two strains, the presence of K. marxiensis GY1 significantly increased the gastrointestinal tolerance, aggregation, and adhesion characteristics of L. helveticus SNA12. In order to investigate the flavor changes, digestive characteristics, and antioxidant properties following co-cultivation fermentation, the optimal fermentation ratio of 8 %-2% (v/v) and fermentation temperature (37 °C) of L. helveticus SNA12-K. marxiensis GY1 were determined. The results of the electronic nose and electronic tongue showed that L. helveticus SNA12-K. marxiensis GY1 could increase the aroma components of fermented milk, such as terpenes and aromatic substances. Meanwhile, dynamic in vitro rat stomach-duodenum model was used to analyse the changes in the digestion of proteins and peptides (<10 kDa), and the results indicated that co-cultivation fermented milk could be digested faster compared to a single fermentation. Furthermore, the antioxidant capacity of co-cultivation fermented milk was higher than that of single fermentation.

Isolation of Bacillus subtilis and Bacillus pumilus with Anti-Vibrio parahaemolyticus Activity and Identification of the Anti-Vibrio parahaemolyticus Substance

The adoption of intensive farming has exacerbated disease outbreaks in aquaculture, particularly vibriosis caused by Vibrio parahaemolyticus. The use of probiotics to control V. parahaemolyticus is recognized as a good alternative to antibiotics for avoiding the development of antibiotic-resistant bacteria. In this study, two strains of B. HLJ1 and B. C1 with strong inhibitory activity on V. parahaemolyticus were isolated from aquaculture water and identified as Bacillus subtilis and Bacillus pumilus, respectively. Both B. HLJ1 and B. C1 lacked antibiotic resistance and virulence genes, suggesting that they are safe for use in aquaculture. In addition, these two strains can tolerate acid environments, produce spores, secrete extracellular enzymes, and co-aggregate as well as auto-aggregate with V. parahaemolyticus. B. HLJ1 and B. C1 produced the same anti-V. parahaemolyticus substance, which was identified as AI-77-F and belongs to amicoumacins. Both B. C1 and B. HLJ1 showed inhibitory activity against 11 different V. parahaemolyticus and could effectively control the growth of V. parahaemolyticus in simulated aquaculture wastewater when the concentration of B. C1 and B. HLJ1 reached 1 × 10⁷ CFU/mL. This study shows that B. HLJ1 and B. C1 have great potential as aquaculture probiotics.

Genome Sequence and Evaluation of Safety and Probiotic Potential of Lactiplantibacillus plantarum LPJZ-658

This study aims to systematically evaluate the safety of a novel L. plantarum LPJZ-658 explored on whole-genome sequence analysis, safety, and probiotic properties assessment. Whole genome sequencing results demonstrated that L. plantarum LPJZ-658 consists of 3.26 Mbp with a GC content of 44.83%. A total of 3254 putative ORFs were identified. Of note, a putative bile saline hydrolase (BSH) (identity 70.4%) was found in its genome. In addition, the secondary metabolites were analyzed, and one secondary metabolite gene cluster was predicted to consist of 51 genes, which verified its safety and probiotic properties at the genome level. Additionally, L. plantarum LPJZ-658 exhibited non-toxic and non-hemolytic activity and was susceptible to various tested antibiotics, indicating that L. plantarum LPJZ-658 was safe for consumption. Moreover, the probiotic properties tests confirm that L. plantarum LPJZ-658 also exhibits tolerance to acid and bile salts, preferably hydrophobicity and auto-aggregation, and excellent antimicrobial activity against both Gram-positive and Gram-negative gastrointestinal pathogens. In conclusion, this study confirmed the safety and probiotic properties of L. plantarum LPJZ-658, suggesting it can be used as a potential probiotic candidate for human and animal applications.

Harnessing the probiotic properties and immunomodulatory effects of fermented food-derived Limosilactobacillus fermentum strains: implications for environmental enteropathy

Introduction

Environmental enteropathy (EE), a chronic small intestine disease characterized by gut inflammation, is widely prevalent in low-income countries and is hypothesized to be caused by continuous exposure to fecal contamination. Targeted nutritional interventions using potential probiotic strains from fermented foods can be an effective strategy to inhibit enteric pathogens and prevent chronic gut inflammation.

Methods

We isolated potential strains from fermented rice water and lemon pickle and investigated their cell surface properties, antagonistic properties, adhesion to HT-29 cells, and inhibition of pathogen adherence to HT-29 cells. Bacteriocin-like inhibitory substances (BLIS) were purified, and in vivo, survival studies in Caenorhabditis elegans infected with Salmonella enterica MW116733 were performed. We further checked the expression pattern of pro and anti-inflammatory cytokines (IL-6, IL8, and IL-10) in HT-29 cells supplemented with strains.

Results

The strains isolated from rice water (RS) and lemon pickle (T1) were identified as Limosilactobacillus fermentum MN410703 and MN410702, respectively. Strains showed probiotic properties like tolerance to low pH (pH 3.0), bile salts up to 0.5%, simulated gastric juice at low pH, and binding to extracellular matrix molecules. Auto-aggregation of T1 was in the range of 85% and significantly co-aggregated with Klebsiella pneumoniae, S. enterica, and Escherichia coli at 48, 79, and 65%, respectively. Both strains had a higher binding affinity to gelatin and heparin compared to Bacillus clausii. Susceptibility to most aminoglycoside, cephalosporin, and macrolide classes of antibiotics was also observed. RS showed BLIS activity against K. pneumoniae, S. aureus, and S. enterica at 60, 48, and 30%, respectively, and the protective effects of BLIS from RS in the C. elegans infection model demonstrated a 70% survival rate of the worms infected with S. enterica. RS and T1 demonstrated binding efficiency to HT-29 cell lines in the 38-46% range, and both strains inhibited the adhesion of E. coli MDR and S. enterica. Upregulation of IL-6 and IL-10 and the downregulation of IL-8 were observed when HT-29 cells were treated with RS, indicating the immunomodulatory effects of the strain.

Discussion

The potential strains identified could effectively inhibit enteric pathogens and prevent environmental enteropathy.

Novel yeasts with potential probiotic characteristics isolated from the endogenous ferment of artisanal Minas cheese

Artisanal Minas cheese (QMA) is traditionally elaborate using raw milk and endogenous ferment (pingo - whey or rala - grated ripened cheese). In the present study, 91 yeast strains were isolated and identified from pingo and rala. Eight yeast species were identified by the MALDI-TOF mass spectrometry and confirmed by sequencing of the ITS region. The yeasts' protease and lipase activities were evaluated in addition to probiotic properties such as tolerance to low pH and bile salts, hydrophobicity, autoaggregation, co-aggregation with pathogens, and antimicrobial susceptibility. The rala ferment showed a greater variety of species. Yarrowia lipolytica was the dominant specie (52.7% of isolates), followed by the Kluyveromyces lactis and Kodamaea ohmeri (9.9 and 6.6%, respectively). From the total yeasts evaluated, 74 strains showed positive enzymatic activity: 52 strains showed lipolytic (51 Y. lipolytica and one Trichosporon japonicum) and 44 proteolytic activities (18 Y. lipolytica, 13 K. ohmeri, 11 K. lactis, and 2 Wickerhamiella sp.). All evaluated isolates demonstrated tolerance to pH 2.0, and 69 isolates supported the presence of bile salts. From them, 12 isolates showed the capacity of autoaggregation (> 30%) and hydrophobicity (> 90.0%) and were then selected for co-aggregation and antibiotic resistance assays. All selected isolates showed co-aggregation with Salmonella Enteritidis, Escherichia coli, and Listeria monocytogenes greater than 30%. None of the yeast showed sensibility to the evaluated antibiotics and antagonistic activity against the evaluated pathogens. The results demonstrated that pingo and rala have different yeast composition with different enzymatic activity, which may affect the characteristics of the cheese. Furthermore, some yeast strains: Y. lipolytica (9 strains isolated from rala) and K. ohmeri (3 strains isolated from pingo) demonstrated attractive probiotic potential.

Assessing the efficacy of probiotics in augmenting bovine reproductive health: an integrated in vitro, in silico, and in vivo study

The aim of this study was to isolate and characterize bovine-vaginal probiotics genotypically and phenotypically using in silico and evaluate their in vivo performance in buffaloes with endometritis. For the in vitro isolation and characterization, vaginal swabs were collected from 34 cows and 17 buffaloes, and 709 primary bacterial isolates with probiotic activity were obtained using MRS agar media. Two isolates Lactiplantibacillus plantarum KUGBRC (LPKUGBRC) and Pediococcus pentosaceus GBRCKU (PPGBRCKU) demonstrated optimum in vitro probiotic activities as compared to Lacticaseibacillus rhamnosus GG including, acid production, secretion of fatty acids and exopolysaccharide, cell surface hydrophobicity, self-aggregating and co-aggregating capacity with pathogens, anti-microbial activity and bacteriocin-like compounds against pathogens Escherichia coli and Staphylococcus aureus in cell-free supernatant and absence of hemolytic activity. Their phenotypic capacity was confirmed by analyzing the whole genome sequencing data and identifying genes and pathways associated with probiotic properties. These probiotic isolates have shown no virulence genes were discovered in their genomic study. In vivo study of 92 buffaloes suffering from clinical endometritis with purulent cervico-vaginal mucus (CVM) were randomly allocated 40 × 10⁸ CFU/ml LPKUGBRC and PPGBRCKU and 40 ml Normal saline. The LPKUGBRC reduced the duration between administration of probiotic to induction of healthy estrus significantly. However, no effect was observed on pregnancy rate. These results suggest that LPKUGBRC and PPGBRCKU probiotic bacteria demonstrate probiotic efficiency and adaptability. Further sourced from the same niche as the targeted infection, they offer a distinct advantage in targeting the specific microbial population associated with endometritis. The findings of this study highlight the potential of LPKUGBRC and PPGBRCKU probiotics in treating endometritis and suggest further exploration of their clinical applications.

Celebrating 50 years of microbial granulation technologies: From canonical wastewater management to bio-product recovery

Microbial granulation technologies (MGT) in wastewater management are widely practised for more than fifty years. MGT can be considered a fine example of human innovativeness-driven nature wherein the manmade forces applied during operational controls in the biological process of wastewater treatment drive the microbial communities to modify their biofilms into granules. Mankind, over the past half a century, has been refining the knowledge of triggering biofilm into granules with some definite success. This review captures the journey of MGT from inception to maturation providing meaningful insights into the process development of MGT-based wastewater management. The full-scale application of MGT-based wastewater management is discussed with an understanding of functional microbial interactions within the granule. The molecular mechanism of granulation through the secretion of extracellular polymeric substances (EPS) and signal molecules is also highlighted in detail. The recent research interest in the recovery of useful bioproducts from the granular EPS is also emphasized.

Whole Genome Sequencing of the Novel Probiotic Strain Lactiplantibacillus plantarum FCa3L

Lactiplantibacillus plantarum is best known for its significant adaptive potential and ability to colonize different ecological niches. Different strains of L. plantarum are widely used as probiotics. To characterize the probiotic potential of the novel L. plantarum FCa3L strain isolated from fermented cabbage, we sequenced its whole genome using the Illumina MiSeq platform. This bacterial isolate had a circular chromosome of 3,365,929 bp with 44.3% GC content and a cyclic phage phiX174 of 5386 bp with 44.7% GC content. The results of in vitro studies showed that FCa3L was comparable with the reference probiotic strain L. plantarum 8PA3 in terms of acid and bile tolerance, adhesiveness, H₂O₂ production, and acidification rate. The strain 8PA3 possessed higher antioxidant activity, while FCa3L demonstrated superior antibacterial properties. The antibiotic resistance of FCa3L was more relevant to the probiotic strain than that of 8PA3, although a number of silent antibiotic resistance genes were identified in its genome. Genomic evidence to support adhesive and antibacterial properties, biosynthesis of bioactive metabolites, and safety of FCa3L was also presented. Thus, this study confirmed the safety and probiotic properties of L. plantarum FCa3L via complete genome and phenotype analysis, suggesting its potential as a probiotic, although further in vivo investigations are still necessary.

Different cellular fatty acid pattern and gene expression of planktonic and biofilm state Listeria monocytogenes under nutritional stress

Listeria monocytogenes is a Gram-positive bacterium frequently involved in food-borne disease outbreaks and is widely distributed in the food-processing environment. This work aims to depict the impact of nutrition deficiency on the survival strategy of L. monocytogenes both in planktonic and biofilm states. In the present study, cell characteristics (autoaggression, hydrophobicity and motility), membrane fatty acid composition of MRL300083 (Lm83) in the forms of planktonic and biofilm-associated cells cultured in TSB-YE and 10-fold dilutions of TSB-YE (DTSB-YE) were investigated. Additionally, the relative expression of related genes were also determined by RT-qPCR. It was observed that cell growth in different bacterial life modes under nutritional stress rendered the cells a distinct phenotype. The higher autoaggression (AAG) and motility of the planktonic cells in DTSB-YE is associated with better biofilm formation. An increased proportion of unsaturated fatty acid/saturated fatty acid (USFA/SFA) indicates more fluidic biophysical properties for cell membranes of L. monocytogenes in planktonic and biofilm cells in DTSB-YE. Biofilm cells produced a higher percentage of USFA and straight fatty acids than the corresponding planktonic cells. An appropriate degree of membrane fluidity is crucial for survival, and alteration of membrane lipids is an essential adaptive response. The adaptation of bacteria to stress is a multifactorial cellular process, the expression of flagella-related genes fliG, fliP, flgE and the two-component chemotactic system cheA/Y genes of planktonic cells in DTSB-YE significantly increased compared to that in TSB-YE (p < 0.05). This study provides new information on the role of the physiological adaptation and gene expression of L. monocytogenes for planktonic and biofilm growth under nutritional stress.

Probiotic potential of Saccharomyces cerevisiae GILA with alleviating intestinal inflammation in a dextran sulfate sodium induced colitis mouse model

Recently, several probiotic products have been developed; however, most probiotic applications focused on prokaryotic bacteria whereas eukaryotic probiotics have received little attention. Saccharomyces cerevisiae yeast strains are eukaryotes notable for their fermentation and functional food applications. The present study investigated the novel yeast strains isolated from Korean fermented beverages and examined their potential probiotic characteristics. We investigated seven strains among 100 isolates with probiotic characteristics further. The strains have capabilities such as auto-aggregation tendency, co-aggregation with a pathogen, hydrophobicity with n-hexadecane,1,1-diphenyl-2-picrylhydrazyl scavenging effect, survival in simulated gastrointestinal tract conditions and the adhesion ability of the strains to the Caco-2 cells. Furthermore, all the strains contained high cell wall glucan content, a polysaccharide with immunological effects. Internal transcribed spacer sequencing identified the Saccharomyces strains selected in the present study as probiotics. To examine the effects of alleviating inflammation in cells, nitric oxide generation in raw 264.7 cells with S. cerevisiae showed that S. cerevisiae GILA could be a potential probiotic strain able to alleviate inflammation. Three probiotics of S. cerevisiae GILA strains were chosen by in vivo screening with a dextran sulfate sodium-induced colitis murine model. In particular, GILA 118 down-regulates neutrophil-lymphocyte ratio and myeloperoxidase in mice treated with DSS. The expression levels of genes encoding tight junction proteins in the colon were upregulated, cytokine interleukin-10 was significantly increased, and tumor necrosis factor-α was reduced in the serum.

Evaluation of Bacillus paramycoides Strains Isolated from Channa Fish sp. on Growth Performance of Labeo rohita Fingerlings Challenged by Fish Pathogen Aeromonas hydrophila MTCC 12301

Probiotics play vital roles in improving growth, survival, and immune responses and inhibit the growth of pathogenic bacteria in freshwater fish. This study was conducted to isolate potential probiotics from Channa punctatus and Channa striatus and to evaluate their effect on Labeo rohita fingerlings. Among the isolates, Bacillus paramycoides PBG9D and BCS10 (1) exhibited antimicrobial activity against the fish pathogen Aeromonas hydrophila. Both strains showed tolerance to acidic and alkaline pH (2, 3, 4, 7, and 9) and bile salts (0.3%) and exhibited strong adhesion capacity. After in-vitro assessment, these strains were evaluated on the growth performances of rohu fingerlings challenged by Aeromonas hydrophila for 4 weeks. The study consisted of six groups, each containing 6 fish. Group (I) was the control, fed a basal diet; group (II) contained a pathogen and was also fed a basal diet; group (III & IV) was given a probiotic supplemented experimental diet; Fourth group (V & VI) contained a pathogen and was given a probiotic supplemented experimental diet. After the 12th day of experiment, rohu fingerlings of pathogen (II) and probiotic + pathogen (V & VI) groups were intraperitoneally injected with 0.1 mL of Aeromonas hydrophila. After 4 weeks, no significant differences in weight gain, weight gain %, and feed conversion ratio were observed in probiotic (III & IV)- fed groups compared to control. However, the specific growth rate was significantly improved in probiotic fed groups compared to other groups. Survival rate and condition factor were significantly similar in all groups. After injection, abnormal swimming, loss of appetite and weight loss were observed in the pathogen (II) group, while no such symptoms were found in the probiotic + pathogen (V & VI)- groups, confirming the effects of probiotics. The overall results of the study revealed that dietary supplementation with Bacillus paramycoides strains could improve the specific growth rate and disease resistance against Aeromonas hydrophila in Labeo rohita.

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.

Hormonal drugs: Influence on growth, biofilm formation, and adherence of selected gut microbiota

Many studies have reported the influence of hormonal drugs on gut microbiota composition. However, the underlying mechanism of this interaction is still under study. Therefore, this study aimed to evaluate the possible in vitro changes in selected members of gut bacteria exposed to oral hormonal drugs used for years. Selected members of gut bacteria were Bifidobacterium longum, Limosilactobacillus reuteri, Bacteroides fragilis, and Escherichia coli representing the four main phyla in the gut. Selected hormonal drugs used for a long time were estradiol, progesterone, and thyroxine. The effect of intestinal concentrations of these drugs on the selected bacterial growth, biofilm formation, and adherence to Caco-2/HT-29 cell line was assessed. Short-chain fatty acids (SCFAs) have been included in host functions including the gut, immune and nervous functions; thus, the drug’s effects on their production were assayed using High- Performance Liquid Chromatography. Sex steroids significantly increased the growth of all tested bacteria except B. longum, similarly, thyroxine increased the growth of tested Gram-negative bacteria however reducing that of tested Gram-positive bacteria. The effect of drugs on biofilm formation and bacterial adherence to cell lines cocultures was variable. Progesterone decreased the biofilm formation of tested Gram-positive bacteria, it nevertheless increased L. reuteri adherence to Caco-2/HT-29 cell line cell lines coculture. By contrast, progesterone increased biofilm formation by Gram-negative bacteria and increased adherence of B. fragilis to the cell lines coculture. Moreover, thyroxine and estradiol exhibited antibiofilm activity against L. reuteri, while thyroxine increased the ability of E. coli to form a biofilm. Moreover, hormones affected bacterial adherence to cell lines independently of their effect on hydrophobicity suggesting other specific binding factors might contribute to this effect. Tested drugs affected SCFAs production variably, mostly independent of their effect on bacterial growth. In conclusion, our results showed that the microbiota signature associated with some hormonal drug consumption could be the result of the direct effect of these drugs on bacterial growth, and adherence to enterocytes besides the effect of these drugs on the host tissue targets. Additionally, these drugs affect the production of SCFAs which could contribute to some of the side effects of these drugs.

In vitro evaluation of probiotic properties of Lactobacillus acidophilus AD125 and antagonism against Escherichia coli O157:H7 adhesion to Caco-2 cell

This study investigated the in vitro antibacterial activity of Lactobacillus acidophilus AD125 against Escherichia coli (E. coli) O157:H7 and its probiotic properties: gastrointestinal tolerance, surface hydrophobicity, autoaggregation, coaggregation, and adhesion to Caco-2 cells. In addition, the action mode of the strain's antagonism against adhesion of E. coli O157:H7 to Caco-2 cells was analyzed, and related substances were also determined. Results showed that L. acidophilus AD125 had stronger antibacterial activity (inhibition zone of 20.47 ± 0.43 for AD125 culture solution and 14.55 ± 1.12 for cell-free supernatant) against E. coli O157:H7 than other Lactobacillus spp. Also, this strain had higher gastrointestinal tolerance, autoaggregation percentage (26.51 ± 0.71%), and coaggregation percentage (23.97 ± 0.44%) with E. coli O157:H7. High surface hydrophobicity of toluene and xylene (83.59 ± 2.54% and 93.45 ± 1.24%) was also observed. Bacterial adhesion counts were 1176.54 100 per cells, indicating good adhesion to Caco-2 cells. Furthermore, the exclusion, competition, and antibacterial effect of AD125 may have driven its antagonism against E. coli O157:H7 adhesion. Finally, surface-layer proteins, extracellular polysaccharides, and thermosensitive substances all participated in the antagonism against E. coli O157:H7, with surface-layer proteins the main related substances. These results show that Lactobacillus acidophilus AD125 is promising for inhibiting E. coli O157:H7 and preventing and treating intestinal diseases induced by E. coli O157:H7.

In-vitro and in-vivo antibacterial activity of potential probiotic Lactobacillus paracasei against Staphylococcus aureus and Escherichia coli

Previous studies documented that Lactobacillus paracasei has obvious in vitro cholesterol-lowering abilities. In this study, initially, L. paracasei was tested in terms of antibacterial properties as well as antibiogram profile. Then, the safety of the mentioned strain was evaluated in rats. Evaluation of antibiotic susceptibility revealed that the L. paracasei strain had high antibiotic resistance to several antibiotics as well as a great ability to autoaggregation. After identification of the probiotic aptitude, six groups of six rats from both sexes were used (three groups of each sex). L. paracasei was administered to the experimental groups via drinking water for 28 days (1 × 108 and 1 × 109, respectively). The negative control group received only tap water during this period. Hematological indicators, serum liver enzyme activity including (alanine transaminase (ALT), alkaline phosphatase (ALP), and aspartate transaminase (AST)) as well as serum creatinine and urea were evaluated at the end of 28 days. The blood and serum factors were not changed significantly during the 28 days. The only noticeable difference was the increase of blood urea in both sexes which was in a normal range. Furthermore, the evaluation of antagonistic properties revealed that L. paracasei had antibacterial aptitude against Escherichia coli and Staphylococcus aureus. In conclusion, this strain has good cholesterol-lowering and antibacterial properties and is a safe supplement in Wistar rats.

Gut microbiota modulation via short-term administration of potential probiotic kefir yeast Kluyveromyces marxianus A4 and A5 in BALB/c mice

Kefir yeast, Kluyveromyces marxianus, has been evaluated for its potential probiotic properties-survivability, non-pathogenicity, and antioxidant and anti-microbial activities. However, host gut microbiota modulation of kefir yeasts remains unclear. Here, we compared kefir yeast strains K. marxianus A4 (Km A4) and K. marxianus A5 (Km A5) with Saccharomyces boulardii ATCC MYA-796 (Sb MYA-796) by investigating their adherence to colorectal adenocarcinoma (Caco-2) cells and gut microbiota modulation in BALB/c mice. The kefir yeast strains exhibited higher intestinal cell adhesion than Sb MYA-796 (p < 0.05). Bacteroidetes, Bacteroidales, and Bacteroides were more abundant in the 1 × 108 CFU/mL of Km A4 treatment group than in the control group (p < 0.05). Moreover, 1 × 108 CFU/mL of Km A5 increased Corynebacteriales and Corynebacterium compared to the 1 × 108 CFU/mL of Km A4 treatment group (p < 0.01). The results showed that Km A4 and Km A5 had good Caco-2 cell adhesion ability and modulated gut microbiota upon short-term administration in healthy mice.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01268-3.

Fish Probiotics: Cell Surface Properties of Fish Intestinal Lactobacilli and Escherichia coli

The properties of intestinal bacteria/probiotics, such as cell surface hydrophobicity (CSH), auto-aggregation, and biofilm formation ability, play an important role in shaping the relationship between the bacteria and the host. The current study aimed to investigate the cell surface properties of fish intestinal bacteria and probiotics. Microbial adhesion to hydrocarbons was tested according to Kos and coauthors. The aggregation abilities of the investigated strains were studied as described by Collado and coauthors. The ability of bacterial isolates to form a biofilm was determined by performing a qualitative analysis using crystal violet staining based on the attachment of bacteria to polystyrene. These studies prove that bacterial cell surface hydrophobicity (CSH) is associated with the growth medium, and the effect of the growth medium on CSH is species-specific and likely also strain-specific. Isolates of intestinal lactobacilli from fish (Salmo ischchan) differed from isolates of non-fish/shrimp origin in the relationship between auto-aggregation and biofilm formation. Average CSH levels for fish lactobacilli and E. coli might were lower compared to those of non-fish origin, which may affect the efficiency of non-fish probiotics use in fisheries due to the peculiarities of the hosts’ aquatic lifestyles.

Probiotic Potential and Safety Assessment of Type Strains of Weissella and Periweissella Species

Although numerous strains belonging to the Weissella genus have been described in the last decades for their probiotic and biotechnological potential, others are known to be opportunistic pathogens of humans and animals. Here, we investigated the probiotic potential of two Weissella and four Periweissella type strains belonging to the species Weissella diestrammenae, Weissella uvarum, Periweissella beninensis, Periweissella fabalis, Periweissella fabaria, and Periweissella ghanensis by genomic and phenotypic analyses, and performed a safety assessment of these strains. Based on the results of the survival to simulated gastrointestinal transit, autoaggregation and hydrophobicity characteristics, as well as adhesion to Caco-2 cells, we showed that the P. beninensis, P. fabalis, P. fabaria, P. ghanensis, and W. uvarum type strains exhibited a high probiotic potential. The safety assessment, based on the genomic analysis, performed by searching for virulence and antibiotic resistance genes, as well as on the phenotypic evaluation, by testing hemolytic activity and antibiotic susceptibility, allowed us to identify the P. beninensis type strain as a safe potential probiotic microorganism. IMPORTANCE A comprehensive analysis of safety and functional features of six Weissella and Periweissella type strains was performed. Our data demonstrated the probiotic potential of these species, indicating the P. beninensis type strain as the best candidate based on its potential probiotic features and the safety assessment. The presence of different antimicrobial resistance profiles in the analyzed strains highlighted the need to establish cutoff values to perform a standardized safety evaluation of these species, which, in our opinion, should be mandatory on a strain-specific basis.

Limosilactobacillus fermentum 3872 That Produces Class III Bacteriocin Forms Co-Aggregates with the Antibiotic-Resistant Staphylococcus aureus Strains and Induces Their Lethal Damage

LF3872 was isolated from the milk of a healthy lactating and breastfeeding woman. Earlier, the genome of LF3872 was sequenced, and a gene encoding unique bacteriocin was discovered. We have shown here that the LF3872 strain produces a novel thermolabile class III bacteriolysin (BLF3872), exhibiting antimicrobial activity against antibiotic-resistant Staphylococcus aureus strains. Sequence analysis revealed the two-domain structural (lysozyme-like domain and peptidase M23 domain) organization of BLF3872. At least 25% residues of this protein are expected to be intrinsically disordered. Furthermore, BLF3872 is predicted to have a very high liquid-liquid phase separation. According to the electron microscopy data, the bacterial cells of LF3872 strain form co-aggregates with the S. aureus 8325-4 bacterial cells. LF3872 produced bacteriolysin BLF3872 that lyses the cells of the S. aureus 8325-4 mastitis-inducing strain. The sensitivity of the antibiotic-resistant S. aureus collection strains and freshly isolated antibiotic-resistant strains was tested using samples from women with lactation mastitis; the human nasopharynx and oral cavity; the oropharynx of pigs; and the cows with a diagnosis of clinical mastitis sensitive to the lytic action of the LF3872 strain producing BLF3872. The co-cultivation of LF3872 strain with various antibiotic-resistant S. aureus strains for 24 h reduced the level of living cells of these pathogens by six log. The LF3872 strain was found to be able to co-aggregate with all studied S. aureus strains. The cell-free culture supernatant of LF3872 (CSLF3872) induced S. aureus cell damage and ATP leakage. The effectiveness of the bacteriolytic action of LF3872 strain did not depend on the origin of the S. aureus strains. The results reported here are important for the creation of new effective drugs against antibiotic-resistant strains of S. aureus circulating in humans and animals.

Isolation and Identification of Limosilactobacillus reuteri PSC102 and Evaluation of Its Potential Probiotic, Antioxidant, and Antibacterial Properties

We isolated and characterized Limosilactobacillus reuteri PSC102 and evaluated its probiotic, antioxidant, and antibacterial properties. We preliminarily isolated 154 candidates from pig feces and analyzed their Gram nature, morphology, and lactic acid production ability. Based on the results, we selected eight isolates and tested their ability to produce digestive enzymes. Finally, we identified one isolate using 16S rRNA gene sequencing, namely, L. reuteri PSC102. We tested its probiotic properties in vitro, including extracellular enzyme activities, low pH and bile salt tolerance, autoaggregation and coaggregation abilities, adhesion to Caco-2 cells, antibiotic susceptibility, and hemolytic and gelatinase activities. Antioxidant activity was determined using 1-diphenyl-2-picrylhydrazyl and 2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging and reducing power assays. The antibacterial activity of this strain and its culture supernatant against enterotoxigenic Escherichia coli were evaluated using a time-kill assay and disk diffusion method, respectively. L. reuteri PSC102 exhibited tolerance toward low pH and bile salt and did not produce harmful enzymes or possess hemolytic and gelatinase activities. Its intact cells and cell-free extract exhibited potential antioxidant activities, and significantly inhibited the growth of enterotoxigenic E. coli. Our results demonstrate that L. reuteri PSC102 is a potential probiotic candidate for developing functional feed.

First isolation of a probiotic candidate Enterococcus mundtii from Herniaria glabra L. and evaluation of its wound healing activity

In this study focused on probiotic properties of bacterium isolated from Herniaria glabra L. is a medicinal plant. The bacterium was isolated from H. glabra, and it was identified using the molecular method as Enterococcus mundtii AF-1 strain. Antibiotic sensitivity tests showed that AF-1 strain was sensitive to streptomycin, tobramycin, gentamicin, imipenem, erythromycin, and ciprofloxacin. The strain exhibited γ-haemolytic activity. These results show that the strain can be considered safe. The AF-1 strain showed inhibitory activity against some pathogens, including Bacillus subtilis, Klebsiella pneumoniae, and Yersinia pseudotuberculosis. Additionally, AF-1 strain exhibited high tolerance to low pH, pepsin, pancreatin, and bile salts. These properties showed that the strain may survival under the gastrointestinal conditions. The strain showed 40% DPPH free radical scavenging activity. The autoaggregation rate of the strain was 72.46% and the strain exhibited the high coaggregation rate (70.77% with Escherichia coli, and 63.78% with Listeria monocytogenesis). AF-1 strain showed 38.10% adhesion towards n-hexane, and 47.62% adhesion toward chloroform. It has been found to have moderate hydrophobicity. These results demonstrated the beneficial colonization ability of the strain in the gut. Furthermore, it was observed that living cells of AF-1 strain showed healing activity in the artificial wound area. Result of studies, it is seen that AF-1 strain might be excellent a probiotic candidate.

Evaluation of Antimicrobial, Antiadhesive and Co-Aggregation Activity of a Multi-Strain Probiotic Composition against Different Urogenital Pathogens

The urogenital microbiota is dominated by Lactobacillus that, together with Bifidobacterium, creates a physiological barrier counteracting pathogen infections. The aim of this study was to evaluate the efficacy of a multi-strain probiotic formulation (Lactiplantibacillus plantarum PBS067, Lacticaseibacillus rhamnosus LRH020, and Bifidobacterium animalis subsp. lactis BL050) to inhibit adhesion and growth of urogenital pathogens. The antimicrobial and antiadhesive properties of the probiotic strains and their mixture were evaluated on human vaginal epithelium infected with Candida glabrata, Neisseria gonorrheae, Trichomonas vaginalis, and Escherichia coli-infected human bladder epithelium. The epithelial tissue permeability and integrity were assessed by transepithelial/transendothelial electrical resistance (TEER). Co-aggregation between probiotics and vaginal pathogens was also investigated to elucidate a possible mechanism of action. The multi-strain formulation showed a full inhibition of T. vaginalis, and a reduction in C. glabrata and N. gonorrheae growth. A relevant antimicrobial activity was observed for each single strain against E. coli. TEER results demonstrated that none of the strains have negatively impaired the integrity of the 3D tissues. All the probiotics and their mixture were able to form aggregates with the tested pathogens. The study demonstrated that the three strains and their mixture are effective to prevent urogenital infections.

Bioprospecting of the probiotic potential of yeasts isolated from a wine environment

Autochthonous yeasts of oenological origin are adapted to highly stressful and selective environments, which makes them potential candidates for probiotics. The objective of the present study was to explore the probiotic potential of 96 native yeasts of oenological origin, their biosafety, resistance to gastrointestinal tract conditions and adhesion properties. Regarding biosafety, 66 isolates shown negative hemolytic activity, negative urease activity and susceptibility to 3 or more antifungals. After the gastrointestinal resistance test, 15 isolates were selected that showed growth at different temperatures, tolerance to low pH and the presence of bile salts in in vitro tests. In general, survival after simulated conditions of the gastrointestinal tract was high and more restrictive was the duodenal. The results of the adhesion properties showed highly variable hydrophobicity and a high percentage of autoaggregation at 24 h. The maximum production of biofilm was detected in the Pichia strains. Of a total of 96 yeast strains, 15 non-Saccharomyces yeasts presented suitable properties as probiotic candidates. The native winemaking strains performed better than the reference probiotic strain, Saccharomyces cerevisiae var. boulardii CNCM I-745, which reaffirms that these strains are promising probiotic candidates and further studies are necessary to confirm their probiosis.

Red ginseng dietary fiber promotes probiotic properties of Lactiplantibacillus plantarum and alters bacterial metabolism

Korean red ginseng has been widely used as an herbal medicine. Red ginseng dietary fiber (RGDF) is a residue of the processed ginseng product but still contains bioactive constituents that can be applied as prebiotics. In this study, we evaluated changes on fermentation profiles and probiotic properties of strains that belong to family Lactobacillaceae with RGDF supplementation. Metabolomic analyses were performed to understand specific mechanisms on the metabolic alteration by RGDF and to discover novel bioactive compounds secreted by the RGDF-supplemented probiotic strain. RGDF supplementation promoted short-chain fatty acid (SCFA) production, carbon source utilization, and gut epithelial adhesion of Lactiplantibacillus plantarum and inhibited attachment of enteropathogens. Intracellular and extracellular metabolome analyses revealed that RGDF induced metabolic alteration, especially associated with central carbon metabolism, and produced RGDF-specific metabolites secreted by L. plantarum, respectively. Specifically, L. plantarum showed decreases in intracellular metabolites of oleic acid, nicotinic acid, uracil, and glyceric acid, while extracellular secretion of several metabolites including oleic acid, 2-hydroxybutanoic acid, hexanol, and butyl acetate increased. RGDF supplementation had distinct effects on L. plantarum metabolism compared with fructooligosaccharide supplementation. These findings present potential applications of RGDF as prebiotics and bioactive compounds produced by RGDF-supplemented L. plantarum as novel postbiotic metabolites for human disease prevention and treatment.

The Emerging Role of Probiotics and their Derivatives against Biofilm-Producing MRSA: A Scoping Review

Background

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the main bacterial pathogens causing chronic infections, mainly because of its capacity to produce biofilm. Biofilm production is one of the underlying strategies for antibacterial drug resistance. Accordingly, preventing and attenuating biofilm production has become an emerging approach to controlling persistent infections. Therefore, this scoping review is aimed at surveying the published literature describing the usage of probiotics and their derivatives against biofilm-producing MRSA.

Methods

Updated literature searches were conducted across seven electronic databases including Web of Science, PubMed, Scopus, Cochrane Library, ProQuest, Embase, and Google Scholar to identify all original published articles about probiotics against MRSA. In this regard, studies were summarized and analyzed in the present review.

Results

In the reviewed studies, various microorganisms and compounds were used as probiotics as follows: Lactobacillus species (8 studies), Enterococcus species (4 studies), Bacillus species (2 studies), Streptomyces species (2 studies), Saccharomyces cerevisiae (1 study), Corynebacterium accolens (1 study), and Lactococcus lactis derived Nisin (3 studies). Based on our comprehensive search, 21 studies with eligibility criteria were included in the present review including 12 studies on clinical strains, 6 studies on ATCC, 2 studies simultaneously on clinical and standard strains, and finally 1 study on food sample.

Conclusions

Our study showed that there was an increasing trend in the number of publications reporting probiotics against biofilm-producing MRSA. The results of this scoping review could use to guide the undertaking of the subsequent systematic reviews. In summary, probiotics with antimicrobial and antibiofilm properties can use as an embedded agent in food products or as a biopharmaceutical in the prevention and treatment of MRSA infections.

The Human Milk Microbiota Produces Potential Therapeutic Biomolecules and Shapes the Intestinal Microbiota of Infants

Human milk not only provides a perfect balance of nutrients to meet all the needs of the infant in the first months of life but also contains a variety of bacteria that play a key role in tailoring the neonatal faecal microbiome. Microbiome analysis of human milk and infant faeces from mother-breastfed infant pairs was performed by sequencing the V1-V3 region of the 16S rRNA gene using the Illumina MiSeq platform. According to the results, there is a connection in the composition of the microbiome in each mother-breastfed infant pair, supporting the hypothesis that the infant's gut is colonised with bacteria from human milk. MiSeq sequencing also revealed high biodiversity of the human milk microbiome and the infant faecal microbiome, whose composition changes during lactation and infant development, respectively. A total of 28 genetically distinct strains were selected by hierarchical cluster analysis of RAPD-PCR (Random Amplified Polymorphic DNA-Polymerase Chain Reaction) electrophoresis profiles of 100 strains isolated from human milk and identified by 16S RNA sequencing. Since certain cellular molecules may support their use as probiotics, the next focus was to detect (S)-layer proteins, bacteriocins and exopolysaccharides (EPSs) that have potential as therapeutic biomolecules. SDS-PAGE (Sodium Dodecyl-Sulfate Polyacrylamide Gel Electrophoresis) coupled with LC-MS (liquid chromatography-mass spectrometry) analysis revealed that four Levilactobacillus brevis strains expressed S-layer proteins, which were identified for the first time in strains isolated from human milk. The potential biosynthesis of plantaricin was detected in six Lactiplantibacillus plantarum strains by PCR analysis and in vitro antibacterial studies. ¹H NMR (Proton Nuclear Magnetic Resonance) analysis confirmed EPS production in only one strain, Limosilactobacillus fermentum MC1. The overall microbiome analysis suggests that human milk contributes to the establishment of the intestinal microbiota of infants. In addition, it is a promising source of novel Lactobacillus strains expressing specific functional biomolecules.