Inflammatory bowel disease (IBD) is a chronic immune-inflammatory disease. Gut microbes, intestinal immunity, and gut barrier function play a critical role in IBD. Growing evidence suggests that synbiotic may offer therapeutic benefits for individuals with colitis, suggesting an alternative therapy against colitis. With this in mind, we creatively prepared a new synbiotic combination consisting of a probiotic strain (Limosilactobacillus reuteri) along with one prebiotic chitooligosaccharides (COS). The protective effects of the synbiotic on DSS-induced colitis and the underlying mechanisms were investigated. We demonstrated that the synbiotic ameliorated colitis in mice, as evidenced by a significant remission in body weight loss and colon shortening, and a decreased disease activity index (DAI). Notably, synbiotic reduced the intestinal inflammation and injury by synergistically decreasing inflammatory factors, inhibiting TLR4/Myd88/NF-κB/NLRP3 signaling, preventing macrophage infiltration, and enhancing the integrity of the intestinal barrier. Moreover, synbiotic selectively promoted the growth of beneficial bacteria (e.g., Akkermansia, Lactobacillus) but decreased the pathogenic bacteria (e.g., Helicobacter). BugBase's analysis supported its ameliorated role in reducing pathogenic bacteria. Collectively, our findings revealed the novel synbiotic had a potential to treat colitis, which was associated with its anti-inflammatory and microbiota-balancing properties. This study will contribute to the development of functional synbiotic products for IBD therapy and will provide valuable insights into their mechanisms.

Lacticaseibacillus paracasei K56 (L. paracasei K56) is a probiotic with weight-loss effects. However, symbiosis research on the combined effects of Lacticaseibacillus paracasei K56 and prebiotics is lacking. Therefore, the aim of this study was to investigate the effects of L. paracasei K56, xylooligosaccharide (XOS), galactooligosaccharide (GOS), polyglucose (PG), and their synbiotic combinations (XOS + K56, GOS + K56, and PG + K56) on metabolism and gut composition in children with obesity, using an in vitro fermentation model. Fecal samples were collected from 14 children with obesity for in vitro fermentation, and the effects of the various treatments in gas production and short chain fatty acid synthesis (SCFAs) were assessed. Treatment with probiotics, prebiotics, and synbiotics regulated gut microbiota and metabolites in children with obesity. GOS and XOS had higher degradation rates than PG + K56 synbiotics in the gut microbiota of children with obesity. Moreover, treatment with XOS, GOS, and their synbiotic combinations, (XOS + K56) and (GOS + K56), significantly reduced the production of gas, propionic acid, and butyric acid compared with PG + K56 treatment. Treatments with GOS + K56 and XOS + K56 altered the composition of the gut microbiota, improved the abundance of Bifidobacteria and Lactobacilli, and reduced the abundance of Escherichia/Shigella. Overall, this study provides a theoretical foundation for the use of K56-based synbiotics.

Postharvest losses in fruits and vegetables exert substantial economic and environmental repercussions. Chemical interventions are being widely utilized for the past six decades which may lead to significant health complications. Bioprotection of fruits and vegetables is the need of the hour in which use of lactic acid bacteria (LAB) with GRAS status predominantly stands out. Incorporation of LAB in postharvest fruits and vegetables suppresses the growth of spoilage organisms by synthesizing various antimicrobial compounds such as bacteriocins, organic acids, hydrogen peroxide (HO), exopolysaccharides (EPS), and BLIS. For example, Pediococcus acidilactici, Lactobacillus plantarum, and Limosilactobacillus fermentum convert natural sugars in fruits and vegetables to lactic acid and create an acidic environment that do not favour spoilage organisms. LAB can improve the bioavailability of vitamins and minerals and enrich the phenolic profile and bioactivity components. LAB has remarkable physiological characteristics like resistance towards bacteriophage, proteolytic activity, and polysaccharide production which adds to the safety of foods. They modify the sensory properties and preserve the nutritional quality of fruits and vegetables. They can also perform therapeutic role in the intestinal tract as they tolerate low pH, high salt concentration. Thus application of LAB, whether independently or in conjunction with stabilizing agents as edible coatings, is regarded as an exceptionally promising methodology for ensuring safer consumption of fruits and vegetables. This review addresses the most recent research findings that harness the antagonistic property of lactic acid bacterial metabolites, formulations and coatings containing their bioactive compounds for extended shelf life of fruits and vegetables.

In this study, four lactic acid bacteria (LAB) strains demonstrating ciprofloxacin, bile salt, gastric fluid, and intestinal fluid tolerance as well as adhesion ability to Caco-2 and HT-29 cells were used to improve and recover the intestinal flora disorders caused by ciprofloxacin, among which, Lactobacillus brevis 505 exhibited excellent adhesion ability to two kinds of cells and colonization ability to mouse intestinal. After ciprofloxacin treatment, certain recovery effect on cecum caused by ciprofloxacin in the mice was found during natural recovery (group 5C2), but it was challenging to fully restore the intestinal integrity to the initial level. After L. brevis 505 intervention (group 5C5), the intestinal damage to the colon and ileum caused by ciprofloxacin in mice was significantly alleviated; the recovery effect was better than that of natural recovery. Additionally, L. brevis 505 could effectively regulate INF-γ, sIgA, and RegIIIγ increase induced by ciprofloxacin. Shannon and Simpson index of the intestinal flora of mice in 5C5 group were higher than those in other group, the relative abundance of Bifidobacterium and Lactobacillus in the mice in 5C5 group was increased, indicating that LAB can better restore the structure and abundance of intestinal microflora. Consequently, L. brevis 505 shows promise as a probiotic for gut microbiota restoration and rebuilding during antibiotic therapy.

The rapid increase in microbial antibiotic resistance in Clostridioides difficile (C. difficile) strains and the formation of hypervirulent strains have been associated with a global increase in the incidence of C. difficile infection (CDI) and subsequently, an increase in the rate of recurrence. These consequences have led to an urgent need to develop new and promising alternative strategies to control this pathogen. Engineered probiotics are exciting new bacterial strains produced by editing the genome of the original probiotics. Recently, engineered probiotics have been used to develop delivery vehicles for vaccines, diagnostics, and therapeutics. Recent studies have demonstrated engineered probiotics may potentially be an effective approach to control or treat CDI. This review provides a brief overview of the considerations for engineered probiotics for medicinal use, with a focus on recent preclinical research using engineered probiotics to prevent or treat CDI. We also address the challenges faced in the production of engineered strains and how they may be overcome in the application of these agents to meet patient needs in the future.

Antimicrobial peptides (AMPs) are favoured because of their broad-spectrum antimicrobial properties and because they do not easily develop microbial resistance. However, the low yield and difficult extraction processes of AMPs have become bottlenecks in large-scale industrial applications and scientific research. Microbial recombinant production may be the most economical and effective method of obtaining AMPs in large quantities. In this paper, we review the mechanism, summarize the current status of microbial recombinant production, and focus on strategies to improve the yield and activity of AMPs, in order to provide a reference for their large-scale production.

Clostridial infections, known for their severity and rapid progression, present significant challenges in both clinical and veterinary fields. These bacteria, which can survive without oxygen and produce protective spores, cause many diseases, ranging from simple gastrointestinal disorders to severe and potentially fatal infections including botulism, tetanus, and gas gangrene. The rising occurrence of antibiotic-resistant strains and the repetitive character of some Clostridial illnesses, including Clostridioides difficile infections (CDI), highlight the immediate need for alternate treatment approaches. Postbiotics, which are metabolites derived from probiotics, are showing great potential as effective agents against these diseases. The current study offers a comprehensive investigation of the potential of postbiotics as therapeutic agents for treating Clostridial infections, including C. difficile, Clostridium perfringens, Clostridium botulinum, and Clostridium tetani. It also examines the processes by which postbiotics exert their effects. Preliminary investigations have shown that postbiotics have promising antibacterial and antibiofilm properties, indicating their potential as adjunct agents in methods for controlling microbial growth. Nevertheless, more study is required to thoroughly demonstrate their medicinal uses.

Interest in Saccharomyces and non-Saccharomyces yeasts as biotechnological agents is growing worldwide. Here, Kluyveromyces marxianus GBC2 and two Saccharomyces cerevisiae strains FBZ4 and FBK9 were isolated from pomegranate (Punica granatum) and fig (Ficus carica), respectively, and extensively characterized for their probiotic attributes and health benefits. Overall, these strains were found to be γ-hemolytic, non-cytotoxic against Caco-2 cells, and sensitive to therapeutic antifungals. In terms of probiotic characterization, the strains were able to survive at pH 2 and in 1% bile and had high hydrophobicity and self-aggregation properties, which could explain their ability to form biofilm on a polystyrene and adhere to Caco-2 cells. Adhesion rates of 23.52%, 14.05%, and 9.44% were recorded at 37 °C for K. marxianus GBC2, S. cerevisiae FBK9, and S. cerevisiae FBZ4, respectively. Furthermore, biological screening showed a cholesterol assimilation of 54.32% for K. marxianus GBC2 and almost 33% for both Saccharomyces, more than 73% α-amylase inhibition, and good antioxidant potential for all strains; however, only K. marxianus GBC2 showed antibacterial activity against Staphylococcus aureus ATCC 25923. In light of these findings, the strains could be potential candidates for the development of novel functional foods and for probiotic applications.

To evaluate the impact of Saccharomyces cerevisiae (SC) supplementation on pancreatic islet areas, alpha and beta cell populations, blood glucose levels, and lipid profiles in broilers, broilers were randomly assigned to two groups: a control group (T1) without SC and a treatment group (T2) supplemented with SC. Islet areas, alpha and beta cell counts, serum glucose and insulin levels, and lipid profiles were assessed. SC supplementation significantly decreased blood glucose levels compared to the control group. Additionally, HDL cholesterol levels were elevated in the SC-supplemented group. Although insulin levels remained unchanged, SC supplementation altered the correlation between pancreatic islet areas and alpha and beta cell populations, suggesting a potential influence on pancreatic islet function. Dietary supplementation with Saccharomyces cerevisiae can improve glycemic control and lipid profile in broilers. These findings highlight the potential benefits of using SC as a dietary additive in broiler production.

The occurrence and spread of antimicrobial resistance (AMR) pose a looming threat to human health around the world. Novel antibiotics are urgently needed to address the AMR crisis. In recent years, antimicrobial peptides (AMPs) have gained increasing attention as potential alternatives to conventional antibiotics due to their abundant sources, structural diversity, broad-spectrum antimicrobial activity, and ease of production. Given its significance, there has been a tremendous advancement in the research and development of AMPs. Numerous AMPs have been identified from various natural sources (e.g., plant, animal, human, microorganism) based on either well-established isolation or bioinformatic pipelines. Moreover, computer-assisted strategies (e.g., machine learning (ML) and deep learning (DL)) have emerged as a powerful and promising technology for the accurate prediction and design of new AMPs. It may overcome some of the shortcomings of traditional antibiotic discovery and contribute to the rapid development and translation of AMPs. In these cases, this review aims to appraise the latest advances in identifying and designing AMPs and their significant antimicrobial activities against a wide range of bacterial pathogens. The review also highlights the critical challenges in discovering and applying AMPs.

Candida albicans (C. albicans) is the primary etiologic agent of vaginal candidiasis. Lactobacillus species are predominant in the vaginal microbiome; they inhibit the development of vaginal candidiasis by producing antimicrobial agents, such as lactic acid and hydrogen peroxide. In this study, we investigated the effects of Limosilactobacillus fermentum (L. fermentum) KBL674 in a mouse model of vaginal candidiasis. L. fermentum KBL674 inhibited C. albicans hyphal growth. Moreover, oral administration of L. fermentum KBL674 significantly suppressed vaginal C. albicans infection and associated symptoms, including tissue thickness and immune cell infiltration. A substantial quantity of L. fermentum KBL674 was excreted by the mice within 6 h after oral administration, indicating that most L. fermentum KBL674 did not settle within the gastrointestinal tract. L. fermentum KBL674 modulated gut microbiome diversity, increasing abundances of the genera Akkermansia, Eubacterium, and Faecalibaculum and family Muribaculaceae. Abundances of these bacteria showed negative correlations with the vaginal C. albicans burden in the mouse model, suggesting links between the gut microbiome composition and the vaginal C. albicans burden. Therefore, L. fermentum KBL674 can reduce the vaginal C. albicans burden via direct or indirect inhibition and modulation of the gut microbiome composition preventively.

Helicobacter pylori, a pathogenic bacterium responsible for multiple gastrointestinal disorders, has emerged as a major global concern due to rise in antibiotic resistance. Unwanted side effects of antibiotics therapy are further complicating the treatment strategies. Consequently, an alternative approach, using probiotics has emerged as a promising solution for treating H. pylori infections. Probiotics have shown considerable potential in increasing the cure rate and reducing the side effects through diverse mechanisms. Among the widely employed probiotics, Lactobacillus spp. has garnered particular attention in this review. After reviewing the studies on effects of Lactobacillus spp. on H. pylori, it is evident that several Lactobacillus spp. have demonstrated their potential efficacy against H. pylori infection, when administered alone or in conjunction with antibiotics, in a strain-specific manner. Furthermore, the inclusion of Lactobacillus spp. in the treatment regimen has also been associated with a reduction in the side effects related to antibiotic-based therapies. Future research may focus on identifying optimal strains and treatment regimens, understanding the long-term impacts of use, and determining their role in preventing H. pylori infection in various populations.

A major growing concern in the human and animal health sector is the emergence of antibiotic-resistant pathogenic bacteria due to the indiscriminate use of antibiotics. The exogenous application of bacteriophage endolysins causes abrupt lysis of the bacterial cell wall, which computes them as alternatives to antibiotics. Although naturally occurring endolysins may display limitations in solubility, lytic activity, and narrow lytic spectrum, novel strategies like developing chimeric endolysins and using endolysins in synergism with other antimicrobial agents are required to improve the lytic activity of natural endolysins. The modular structure of endolysins led to the development of novel chimeric endolysins via shuffling enzymatic and cell wall binding domains of different endolysins, using endolysins in a synergistic approach, and their applications in various in vitro and in vivo experiments and different applicable areas. This article aims to review the role of chimeric endolysins and their use in synergistic mode with other biofilm-reducing agents to control biofilm formation and deteriorating pre-formed biofilms in food, dairy, and medical industries. Promoting further development of phage technology and innovation in antibiotic therapy can achieve long-term sustainable development and economic returns.

In the present study, twenty-seven (27) lactobacilli strains, isolated from the vagina of healthy Italian women of reproductive age, were screened for probiotic properties. The strains were evaluated for antagonistic activity against pathogens, adhesion abilities, and potential to displace and/or inhibit the adhesion of previously adhered pathogens as a primary strain selection criterion. Overall, all the tested lactobacilli inhibited at least three pathogens, and the majority of them exhibited antimicrobial activity against Enterobacter cloacae DSM 30054, Pseudomonas aeruginosa DSM 3227, and Pseudomonas aeruginosa DSM 1117. The complete neutralization of antimicrobial activity after cell-free supernatant (CFS) neutralization suggested a pivotal role for lactic acid or other organic acids secreted by the lactobacilli. The strains showed variability in their adhesion levels, but all tested strains adhered to both human colonic epithelial cells (HT-29) and vaginal cells (VK2/E6E7) with adhesion percentages exceeding 1%. The ability to displace or inhibit pathogens was dependent on the pathogen and the lactobacilli strain; the pathogen displacement levels ranged from 9 to 82%, while pathogen exclusion levels varied from 1 to 99%. In conclusion, this study demonstrates the protective effect of vaginal lactobacilli against pathogens and confirms the suitability of the vaginal microbiota as a source of potential probiotic strains. The selected lactobacilli hold promise for the formulation of supplements to enhance genitourinary tract health.

Ensuring the viability and efficacy of probiotic microorganisms during manufacturing and gastrointestinal transit remains challenging, particularly for sensitive strains such as certain lactic acid bacteria and bifidobacteria. This has led to increased interest in spore-forming bacteria, such as Heyndrickxia coagulans (formerly Bacillus coagulans), which can endure environmental stresses through their endospore forms. This study presents a comprehensive analysis of the probiotic potential of strain LMG S-24828, originally isolated from healthy human feces. The genomic analysis confirmed the strain's taxonomic placement within the species H. coagulans and revealed no extrachromosomal plasmid DNA, suggesting genetic stability. Safety assessments demonstrated that LMG S-24828 does not produce D-lactate, deconjugate bile salts, or exhibit hemolytic activity, and it lacks transmissible antibiotic resistances. Phenotypic tests showed the strain's metabolic versatility, including its ability to hydrolyze complex carbohydrates and adhere to intestinal epithelial cells. Moreover, LMG S-24828 exhibited robust survival and germination during in vitro and in vivo gastrointestinal simulations, with evidence of significant spore germination in the human gut. These findings suggest that H. coagulans LMG S-24828 possesses several advantageous traits for probiotic applications, warranting further clinical evaluation to confirm its health benefits.

The surge in bacterial growth and the escalating resistance against a multitude of antibiotic drugs have burgeoned into an alarming global threat, necessitating urgent and innovative interventions. In response to this peril, scientists have embarked on the development of advanced biocompatible antibacterial materials, aiming to counteract not only bacterial infections but also the pervasive issue of food spoilage resulting from microbial proliferation. Protein-based biopolymers and their meticulously engineered composites are at the forefront of this endeavor. Their potential in combating this severe global concern presents an approach that intersects the domains of biomedicine and environmental science. The present review article delves into the intricate extraction processes employed to derive various proteins from their natural sources, unraveling the complex biochemical pathways that underpin their antibacterial properties. Expanding on the foundational knowledge, the review also provides a comprehensive synthesis of functionalized proteins modified to enhance their antibacterial efficacy, unveiling a realm of possibilities for tailoring solutions to specific biomedical and environmental applications. The present review navigates through their antibacterial applications; from wound dressings to packaging materials with inherent antibacterial properties, the potential applications underscore the versatility and adaptability of these materials. Moreover, this comprehensive review serves as a valuable roadmap, guiding future research endeavors in reshaping the landscape of natural antibacterial materials on a global scale.

Lactic acid bacteria (LAB) are widely known for the production of secondary metabolites such as organic acids and other bioactive compounds such as bacteriocins. Finding a broad application in food and healthcare, bacteriocins have received increased attention due to their inherent antimicrobial properties. However, the extraction of bacteriocins is often plagued with low yields due to the complexity of the extraction processes and the diversity of bacteriocins themselves. Here, we review the current knowledge related to bacteriocin extraction on the different extraction techniques for isolating bacteriocins from LAB. The advantages and disadvantages of each technique will also be critically appraised, taking into account factors such as extraction efficiency, scalability and cost-effectiveness. This review aims to guide researchers and professionals in selecting the most suitable approach for bacteriocin extraction from LAB by illuminating the respective advantages and limitations of various extraction techniques.

The aim of the study was the preliminary genetic and phenotypic characterization of a potential probiotic strain of Lactiplantibacillus pentosus (strain krglsrbmofpi2) obtained from traditionally fermented rice. Genome sequencing revealed that the strain has a 3.7-Mb genome with a GC content of 46 and a total of 3192 protein-coding sequences. Using bioinformatic methods, we have successfully identified phage genes, plasmids, pathogenicity, antibiotic resistance and a variety of bacteriocins. Through comprehensive biochemical and biophysical analyses, we have gained valuable insights into its auto-aggregation, co-aggregation, antibiotic resistance, hydrophobicity, antioxidant activity and tolerance to simulated gastrointestinal conditions. The safety evaluation of the isolated L. pentosus was performed on the basis of its haemolytic activity. Our studies have shown that this strain has a strong antagonistic activity against the priority pathogens identified by the World Health Organization such as Vibrio cholerae, Clostridium perfringens, Salmonella enterica subsp. enterica ser. Typhi, Escherichia coli, Listeria monocytogenes and Staphylococcus aureus. It is essential to fully understand the genetic and functional properties of the L. pentosus strain before considering its use as a useful probiotic in the food industry.

We previously observed that supplementation with antimicrobial peptides facilitated the average daily weight gain, net meat, and carcass weights of Holstein bulls. To expand our knowledge of the possible impact of antimicrobial peptides on cecum microbiota, further investigations were conducted. In this study, 18 castrated Holstein bulls with insignificant weight differences and 10 months of age were split randomly into two groups. The control group (CK) was fed a basic diet, whereas the antimicrobial peptide group (AP) was supplemented with 8 g of antimicrobial peptides for 270 days. After slaughter, metagenomic and metabolomic sequencing analyses were performed on the cecum contents. The results showed significantly higher levels of amylase, cellulase, protease, and lipase in the CK than in the AP group (P ≤ 0.05). The levels of β-glucosidase and xylanase (P ≤ 0.05), and acetic and propionic acids (P ≤ 0.01), were considerably elevated in the AP than in the CK group. The metagenome showed variations between the two groups only at the bacterial level, and 3258 bacteria with differences were annotated. A total of 138 differential abundant genes (P < 0.05) were identified in the CAZyme map, with 65 genes more abundant in the cecum of the AP group and 48 genes more abundant in the cecum of the CK group. Metabolomic analysis identified 68 differentially expressed metabolites. Conjoint analysis of microorganisms and metabolites revealed that Lactobacillus had the greatest impact on metabolites in the AP group and Brumimicrobium in the CK group. The advantageous strains of the AP group Firmicutes bacterium CAG:110 exhibited a strong symbiotic relationship with urodeoxycholic acid and hyodeoxycholic acid. This study identified the classification characteristics, functions, metabolites, and interactions of cecal microbiota with metabolites that contribute to host growth performance. Antimicrobial peptides affect the cecal microorganisms, making the use of nutrients more efficient. The utilization of hemicellulose in the cecum of ruminants may contribute more than cellulose to their production performance.

The administration of probiotics for the treatment of different diseases has gained interest in recent years. However, few studies have evaluated their effects on reproductive traits. The objective of this study was to examine the effect of two mixtures of probiotics, a commercial probiotic (Vivomixx®) and a mix of Lacticaseibacillus rhamnosus GG and Faecalibacterium duncaniae A2-165, on sperm quality in a mouse model. Adult male mice (8 months old) were used for two experimental and one control groups (n = 5 each). The probiotics or physiological serum (control) was administered orally, twice a week, during 5 weeks. Sperm were collected from the cauda epididymis, and their total number, motility, kinematics, morphology, and acrosome integrity were assessed in recently collected samples and after a 60-min in vitro incubation. Results showed a higher percentage of normal sperm in both experimental groups, with fewer head abnormalities than in the control. Differences were found among groups in the morphometry of sperm heads, being more elongated in mice treated with probiotics. Sperm from probiotic-treated mice showed similar total motility when compared to the controls, although the proportion of progressively moving sperm and their vigor of motility were lower. Sperm swimming descriptors were measured with a CASA system. Velocity parameters were similar among groups whereas linearity was higher in mice treated with the commercial probiotic. These results suggest that the administration of probiotics may increase the proportion of sperm with normal morphology and lead to modifications in sperm head shape that may enhance sperm swimming. Studies using a longer administration period would be useful in further characterizing the effect of these probiotic mixtures on sperm quality and fertilization capacity.

Direct-fed microorganisms (DFM) are recognized as an alternative to antibiotic-based growth promoters in poultry production due to their health benefits. DFM, however, should undergo rigorous safety testing to ensure they meet the criteria to be "Generally Recognized as Safe." This study assessed eight bacterial consortia (BC) isolated from the ileal and cecal intestinal regions of wild-type chickens, subjecting them to probiotic tests. Subsequently, they were spray- and freeze-dried to evaluate their storage stability for 30 days. BC5-I and BC7-I, isolated from the ileum, emerged as promising DFM, displaying a high content of Lactobacillales using a selective medium and higher susceptibility to Gram-positive and Gram-negative antibiotics. These BC showed a high tolerance to temperature (> 90%), pH > 4 (88-98%), and antagonist effects against Escherichia coli and Salmonella. BC5-I exhibited superior survival in the simulated gastric conditions and satisfactory intestine mucus adhesion. Freeze-drying was the best method to obtain BC5-I and BC7-I powders, with a survival efficiency of 80.3% and 73.2%, respectively, compared to the beginning of storage. BC5-I presented the lowest cell death rate and prolonged half-life through survival storage kinetics. BC5-I only contained Lactobacillus, and Limosilactobacillus reuteri was the predominant species in liquid (78.3%) and freeze-dried (59.8%) forms. BC5-I stands out as a promising Lactobacillus-based DFM that could improve chicken intestinal health and enhance meat and egg production.