Search Results (425)

Background/Objectives: This study evaluated the in vitro probiotic potential of Lactiplantibacillus plantarum Probio87 (Probio87), focusing on its physiological robustness, safety, antimicrobial properties, and anticancer activity, with relevance to vaginal and cervical health. Methods: Tests included acid and bile salt tolerance, mucin adhesion, and carbohydrate utilization. Prebiotic preferences were assessed using FOS, GOS, and inulin. Antibiotic susceptibility was evaluated per EFSA standards. Antimicrobial activity of the cell-free supernatant (CFS) was tested against Staphylococcus aureus, Escherichia coli, and Candida species. Effects on Lactobacillus iners and L. crispatus were analyzed. Anticancer properties were assessed in HeLa, CaSki (HPV-positive), and C-33A (HPV-negative) cervical cancer cell lines through proliferation, apoptosis, angiogenesis, and cell cycle assays. Results: Probio87 showed strong acid and bile tolerance, efficient mucin adhesion, and broad carbohydrate utilization, favoring short-chain prebiotics like FOS and GOS over inulin. It met EFSA antibiotic safety standards. The CFS exhibited potent antimicrobial activity, including complete inhibition of Candida albicans. Probio87 selectively inhibited L. iners without affecting L. crispatus, indicating positive modulation of vaginal microbiota. In cervical cancer cells, the CFS significantly reduced proliferation and angiogenesis markers (p < 0.05), and induced apoptosis and cell cycle arrest in HPV-positive cells, with minimal effects on HPV-negative C-33A cells. Conclusions: Probio87 demonstrates strong probiotic potential, with safe, selective antimicrobial and anticancer effects. Its ability to modulate key microbial and cancer-related pathways supports its application in functional foods or therapeutic strategies for vaginal and cervical health. Full article

Background/Objectives: Early gut colonization by bifidobacteria, occurring more favorably in vaginally born infants than in those delivered via C-section, is crucial for maintaining overall health. The study investigated the health-promoting properties of Limosilactobacillus vaginalis BC17 both as viable cells and as postbiotics (i.e., cell-free supernatant and heat-killed cells), with the purpose of developing oral formulations to support intestinal health. Methods: The safety, effects on the adhesion of bifidobacteria and enteropathogens to intestinal cells, and anti-inflammatory properties of L. vaginalis BC17 viable cells and postbiotics were evaluated. Fast-disintegrating tablets were formulated by freeze-drying cell-free supernatant in combination with heat-killed or viable cells alongside maltodextrins. Results: The formulations were shown to be non-genotoxic and compatible with intestinal cell lines (Caco-2 and HT-29). BC17 viable cells survived in co-culture with intestinal cells up to 48 h and exhibited moderate adhesion to the cell lines. Notably, both BC17 viable cells and postbiotics enhanced the adhesion of beneficial bifidobacteria to Caco-2 cells by up to 250%, while reducing enteropathogens adhesion by 40–70%. Moreover, they exerted significant anti-inflammatory effects, reducing nitric oxide production in macrophages by 40–50% and protecting intestinal cells from SDS-induced damage. The formulations allowed administration of at least 10⁹ BC17 cells in infants and adults through easy and rapid dispersion in milk or water, or directly in the oral cavity without chewing, and preserved their functional properties for up to 3 months of storage. Conclusions: L. vaginalis BC17 viable cells and postbiotics, as well as fast-disintegrating tablets, showed promising functional and safety profiles. Although further in vivo validation is needed, this approach represents a compelling strategy for promoting gut health. Full article

The production of fermented sausages from poultry meat using traditional technologies and natural maturation conditions is a major challenge. The aim of this study was to identify indigenous microbiota with antilisterial activity from an innovative, additive-free, traditionally fermented chicken sausage. Isolates (n = 88) of lactic acid bacteria (LAB) were collected during maturation and subjected to MALDI-TOF mass spectrometry identification. The capacity to combat Listeria was screened against five strains using the agar well diffusion method in 63 selected LAB isolates. MALDI-TOF mass spectrometry identified four different LAB genera, namely Enterococcus, Lactococcus, Leuconostoc and Lactobacillus, the proportions of which differed significantly during the production phases (p < 0.001). Enterococcus faecalis was the most prevalent LAB species in the initial sausage dough. The presence of lactococci (Lactococcus lactis) and enterococci was detected during the 14- and 30-day ripening period and was gradually displaced by leuconostocs and lactobacilli. Lactobacilli appeared to be abundant during the central and late maturation phases, and consisted of only two species—Latilactobacillus sakei and Latilactobacillus curvatus. In total, 38 LAB isolates (60%) showed antilisterial activity toward at least one Listeria indicator strain. The proportions of antilisterial LAB differed significantly during sausage maturation. Inhibitory activity against all indicator Listeria was detected in the neutralized cell-free supernatants of five strains of Enterococcus faecalis, two L. sakei strains and one Leuconostoc mesenteroides strain. The antilisterial activity observed in the indigenous LAB revealed the possible role of L. sakei as a bioprotective culture, as well as the role of Ln. mesenteroides and E. faecalis as bacteriocin producers, for practical applications. Full article

GW4869, a cell-permeable, selective inhibitor of neutral sphingomyelinase is a pharmacological agent that blocks the production and release of extracellular vesicles (EVs). Our previous studies have shown that GW4869 inhibits flaviviral loads in tick, mosquito and mammalian cells, including murine cortical neurons. Yet the mechanism(s) of GW4869 inhibitor upon viral infections were not addressed. In the current study, we focused on how GW4869 interferes with Langat Virus (LGTV, a tick-borne flavivirus) replication in ISE6 tick cells. First, we found that GW4869 is neither cytotoxic at tested doses of 50, 100, and 150 µM in tick cells, nor does it directly bind to the free LGTV present in cell culture supernatants. When tick cells were treated with GW4869, followed by infection with viral stock at dilutions of 10⁻², 10⁻³, 10⁻⁴ (the infectious dose determination by viral dilution assay), it affected LGTV replication in tick cells. A reduction in viral burden was noted in GW4869-treated tick cells, which constituted more than half the amount of decrease when compared to the mock control. Next, GW4869 treatment not only resulted in decreased LGTV transcript levels in tick cells and EVs derived from these infected cells, but also revealed diminished EVs concentrations. Enhanced IsSMase transcripts in the LGTV-infected group was noted upon GW4869 treatment, thus suggesting a host response to perhaps inhibit virus replication. In addition, GW4869 treatment reduced LGTV loads in density gradient EVs fractions, which correlated with decreased EVs concentration in those fractions. These data not only indicate that GW4869 affects LGTV replication, but that it also interferes with EV secretion and release from tick cells. Lastly, we found that GW4869 inhibits LGTV replication in tick cells but does not directly affect the infectivity of LGTV viral particles. Overall, our study suggests that GW4869 is a potential therapeutic inhibitor in controlling tick-borne diseases. Full article

Gamma-aminobutyric acid (GABA) is a non-protein amino acid playing a significant role in the central nervous system and the gut–brain axis. This study investigated the potential to produce GABA by lactic acid bacteria (LAB) isolated from different varieties of organic tomatoes. The isolated LAB were taxonomically identified by 16S rRNA gene sequencing, the presence of the gadB gene (glutamate decarboxylase) was detected, and GABA production was quantified using HPLC. Levilactobacillus brevis CRAI showed the highest GABA production under optimised fermentation conditions with 4% monosodium glutamate (MSG). The genome sequencing of L. brevis CRAI revealed the presence of gadA and gadB isoforms and assessed the strain’s safety profile. The gene expression analysis revealed that the gadA and gadB genes were upregulated in the presence of 4% MSG. The probiotic potential of L. brevis CRAI was also assessed by functional assays. The strain showed strong antimicrobial activity against representative enteropathogens, i.e., Escherichia coli ETEC, Salmonella choleraesuis, and Yersinia enterocolitica, and anti-inflammatory effect, reducing nitric oxide production in LPS-stimulated RAW264.7 macrophages. In addition, its ability to adhere to intestinal epithelial Caco-2 cells was demonstrated. These results highlight L. brevis CRAI as a promising candidate for the development of GABA-enriched functional foods or probiotic supplements with the perspective to modulate the gut-brain axis. Full article

Probiotics have recently gained attention as modulators of the gut–brain axis in neurodegenerative diseases such as Alzheimer’s disease. In this study, we identified probiotic strains with neuroprotective effects and investigated their mechanisms and safety. We screened strains based on their ability to inhibit acetylcholinesterase (AChE) activity and protect cells against H₂O₂-induced damage. The cell-free supernatants (CFS) of Lactobacillus gasseri MG4247 and Lacticaseibacillus rhamnosus MG4644 inhibited AChE activity and reduced cell damage and reactive oxygen species generation. These effects were mediated through inhibition of the MyD88/NF-κB pathway and modulation of the JNK/Bax-dependent apoptotic pathway in neuronal cells treated with H₂O₂. Whole-genome sequencing and antibiotic susceptibility testing confirmed the identity and safety of both strains. These findings suggest that MG4247 and MG4644, as probiotics, may help protect neuronal cells from oxidative stress and inflammation. Full article

Vibrio species are among the primary pathogenic bacteria affecting abalone aquaculture, posing significant threats to farming practices. Current clinical control predominantly relies on antibiotics, which can result in antibiotic residues in both abalone and the surrounding marine environments. Lactobacillus plantarum (LP) has been shown to release bioactive antagonistic substances and exhibits potent inhibitory effects against marine pathogenic bacteria. This study aimed to screen and characterize the probiotic properties of LP strains isolated from rice wine lees to develop a novel biocontrol strategy against Vibriosis in abalone. The methods employed included selective media cultivation, streak plate isolation, and single-colony purification for strain screening, followed by Gram staining, 16S rDNA sequencing, and phylogenetic tree construction using MEGA11 for identification. The resilience, antimicrobial activity, and in vivo antagonistic efficacy of the strains were evaluated through stress tolerance assays, agar diffusion tests, and animal experiments. The results demonstrated the successful isolation and purification of four LP strains (NDMJ-1 to NDMJ-4). Phylogenetic analysis revealed closer genetic relationships between NDMJ-3 and NDMJ-4, while NDMJ-1 and NDMJ-2 were found to be more distantly related. All strains exhibited γ-hemolytic activity, bile salt tolerance (0.3–3.0%), and resistance to both acid (pH 2.5) and alkali (pH 8.5), although they were temperature sensitive (inactivated above 45 °C). The strains showed susceptibility to most of the 20 tested antibiotics, with marked variations in hydrophobicity (1.91–93.15%) and auto-aggregation (13.29–60.63%). In vitro antibacterial assays revealed that cell-free supernatants of the strains significantly inhibited Vibrio parahaemolyticus, V. alginolyticus, and V. natriegens, with NDMJ-4 displaying the strongest inhibitory activity. In vivo experiments confirmed that NDMJ-4 significantly reduced mortality in abalone infected with V. parahaemolyticus. In conclusion, the LP strains isolated from rice wine lees (NDMJ-1 to NDMJ-4) possess robust stress resistance, adhesion capabilities, and broad antibiotic susceptibility. Their metabolites exhibit significant inhibition against abalone-pathogenic Vibrios, particularly NDMJ-4, which demonstrates exceptional potential as a candidate strain for developing eco-friendly biocontrol agents against Vibriosis in abalone aquaculture. Full article

The aims of the present study were to analyze the taxonomic profile and to evaluate the functional effects of sheep FF cultivable microbiota on prepubertal lamb oocytes PLOs developmental potential. Ovarian FFs were recovered from slaughtered adult sheep via the aspiration of developing follicles and used for microbiota propagation. Bacterial pellets underwent 16S rRNA gene sequencing and targeted culturomics, whereas cell-free supernatants were used as supplements for the in vitro maturation (IVM) of slaughtered PLOs. For the first time, bacteria presence in adult sheep FF was detected, with the first report of Streptococcus infantarius subsp. infantarius (as a species) and Burkholderia cepacia (as a genus and species) in either animal or human FF. The short- and long-term effects of bacterial metabolites on PLO maturation and embryonic development were demonstrated. As short-term effects, the addition of FF microbiota metabolites did not affect the oocyte nuclear maturation and mitochondria distribution pattern, except in one of the examined supernatants, which reduced all quantitative bioenergetic/oxidative parameters. As long-term effects, one of them reduced the total cleavage rate after in vitro embryo culture (IVC). In conclusion, microbiota/bacteria are present in adult sheep FF and may influence reproductive outcomes in vitro. Future studies may reveal the beneficial in vitro effects using the microbiome from preovulatory follicles. Full article

The rising prevalence of antibiotic-resistant bacteria demands exploration of alternative antimicrobials. Antimicrobial peptides (AMPs) are a promising group of compounds naturally produced by microorganisms and could serve as potent agents against resistant pathogens. In this study, we evaluated the antimicrobial potential of the cell-free supernatant obtained from Pedobacter silvilitoris—a bacterium originally isolated from decomposing wood—and performed comprehensive genomic screening to uncover novel AMP-encoding genes. The supernatant showed strong inhibitory effects against a diverse selection of pathogens. Scanning electron microscopy (SEM) revealed extensive membrane damage, including pore formation in target bacterial cells, suggesting AMP-mediated activity. A genomic analysis identified 11 candidate AMP genes, named PS_AMP1 to PS_AMP11, based on the significant sequence similarity with known AMPs. Transcriptomic profiling further indicated that several candidates are expressed differentially between the logarithmic and stationary growth phases. Functional assays via gene cloning and peptide synthesis confirmed antimicrobial activity against both Gram-stain-negative and Gram-stain-positive bacteria, with PS_AMP11 emerging as the most effective candidate. Our findings demonstrate that AMPs derived from P. silvilitoris hold substantial promise as alternative antimicrobial agents. Nonetheless, additional structural optimizations may be necessary to fine-tune specificity and to reduce potential host toxicity before clinical deployment. Full article

PLA2G16 is a member of the phospholipase A2 family that catalyzes the generation of lysophosphatidic acids (LPAs) and free fatty acids (FFAs) from phosphatidic acid. Previously, PLA2G16 was found to be a host factor for picornaviruses. Here, we discovered that the Foot-and-Mouth Disease Virus (FMDV) infection led to an elevation in PLA2G16 transcription. We established PLA2G16 overexpression and knockdown cell lines in PK-15 cells to investigate the potential role of PLA2G16 in FMDV infection. Our findings revealed that during FMDV infection, PLA2G16-overexpressing cells had increased levels of phosphorylated STAT1 and the interferon-stimulating factors ISG15 and ISG56. In PLA2G16-overexpressing cells, p-STAT1 was observed at higher levels and earlier than in wild-type cells. Subsequent research demonstrated that PLA2G16 specifically promoted an antiviral innate immune response against FMDV. The host could detect the early release of FMDV viral nucleic acid in PLA2G16-overexpressing cells and trigger the interferon signaling pathway. Additionally, we discovered that the supernatants of PLA2G16-overexpressing cells stimulated the production of higher levels of ISG56 and phosphorylated STAT1. This suggests that PLA2G16-overexpressing cells can activate the innate immune pathway of uninfected cells after FMDV infection. Full article

The search for probiotics to help limit antibiotic resistance is a major scientific challenge. The exploration of Lactobacillus postbiotics represents a promising approach to prevent pathogen invasion. With this aim, Limosilactobacillus fermentum Lf53, with a broad-spectrum of antagonistic activity, was characterized as a candidate probiotic strain with promising transit tolerance and broad spectrum of activity. A study on growth and postbiotic production in modified MRS broth with different carbohydrates and its vegan variant was carried out. This study presents a comprehensive approach to characterizing the anti-virulence properties of postbiotics derived from Lf53. The promising antibacterial, antibiofilm, and anti-quorum sensing activities of the cell-free supernatants (CFS) were assessed as part of the probiotic’s barrier mechanisms. Biofilm inhibition of P. aeruginosa revealed remarkable suppressive effects exerted by the three tested postbiotics, two of which (nCFS and aCFS) exhibited over 50% inhibition and more than 60% for lysates. The postbiotics’ influence on the production of violacein and pyocyanin pigments of Chromobacterium violaceum and Pseudomonas aeruginosa, which are markers for quorum sensing, highlighted their potential in regulating pathogenic mechanisms. The Lf53 lysates showed the most significant inhibition of violacein production across multiple assays, showing 29.8% reduction. Regarding pyocyanin suppression, the postbiotics also demonstrated strong activity. These are the first reported data on complex postbiotics (metabiotics and parabiotics) demonstrating their potential as anti-virulence agents to help combat pathogens associated with antibiotic-resistant infections. Full article

The global market for fresh, ready-to-eat products has grown rapidly, leading to some microbiological safety concerns. Lactic acid bacteria (LAB), along with their metabolites, represent a green alternative to chemical preservatives. For this purpose, the cell-free supernatant of LAB strains previously isolated from fruits and their potential antibacterial effects against pathogens commonly found in minimally processed fruit were evaluated. Based on the preliminary results, a mix of cell-free supernatants (CFSs) was applied as a postbiotic solution in minimally processed orange slices packed in a passive atmosphere. Different pathogenic strains were intentionally inoculated to evaluate their antimicrobial effect, and their trend was monitored. Microbiological and physico-chemical analyses were carried out at different times (3, 8, and 10 days) during cold storage. The CFSs obtained from Lactiplantibacillus plantarum and Leuconostoc mesenteroides strains highlighted an antibacterial activity against Escherichia coli and Staphylococcus aureus in both in vitro and in vivo tests, showing a reduction of 1 Log CFU/mL for E. coli and the disappearance of vital S. aureus. In conclusion, the CFSs can be proposed as an eco-friendly biopreservative for orange slices with a clean label, although their stability needs to be evaluated and their limits of application need to be ruled by specific legislation. Full article

Saccharomyces boulardii (S. boulardii) has attracted widespread attention due to its antimicrobial and anti-inflammatory properties. In this study, we prepared postbiotics from the heat-inactivated cells (HIC) and cell-free supernatant (CFS) of S. boulardii, with the important component L-arginine (Arg) from the metabolic products included as one of the experimental groups. The results showed that in LPS-stimulated Caco-2 cells, HIC, CFS, and Arg protect intestinal epithelial barrier integrity by inhibiting the expression of TNF-α, IL-1β, and IL-6 while enhancing the expression of occludin and ZO-1 proteins. In dextran sulfate sodium (DSS)-induced colitis mice, HIC, CFS, and Arg alleviate symptoms such as weight loss and colonic damage while suppressing the upregulation of pro-inflammatory factors and the downregulation of tight junction proteins. Moreover, these postbiotics help restore the gut microbiota composition and functionality in colitis mice, with potentially superior regulatory effects compared to sulfasalazine (SASP). Overall, HIC and CFS protect the intestinal barrier function and improve DSS-induced colitis, supporting the development of functional food supplements. Full article

The increasing interest in fermented foods stems from their health benefits, mediated by foodborne microorganisms. This study aimed to characterize the fermentative microbiota of Pecorino di Picinisco, a traditional Italian cheese made from ovine raw milk, and to evaluate the probiotic and technological potential of selected lactic acid bacteria strains. Three strains representative of the different species found (Lactococcus lactis, Lactiplantibacillus plantarum and Latilactobacillus curvatus) were chosen and analyzed. All three strains were able to adhere to human intestinal Caco-2 cells, were resistant to simulated in vitro digestion and significantly prolonged the lifespan of Caenorhabditis elegans, used as a simplified in vivo model, with respect to the commercial probiotic strain Lacticaseibacillus rhamnosus GG. The L. plantarum Pic37.4 strain was particularly promising; therefore, its cell-free supernatant was employed to evaluate the antimicrobial activity against indicator strains of foodborne and intestinal pathogens or spoilage bacteria. The results demonstrated the effectiveness of the supernatant against all strains tested, with the strongest effect on the intestinal pathogen enterotoxigenic Escherichia coli K88. In addition, the inhibitory effect on pathogen adhesion to intestinal mucosa was investigated on Caco-2 cells, resulting in a significant reduction in adhesion mediated by the L. plantarum Pic37.4 supernatant. The antimicrobial properties of the L. plantarum strain were confirmed in vivo in C. elegans. These promising results lay the ground for further investigations aimed at substantiating the probiotic and technological potential of the L. plantarum Pic37.4 investigated in this work. Full article

Background/Objectives: Kiperin Postbiotics, defined as non-viable metabolic products derived from probiotics, have gained attention as potential modulators of cellular responses involved in tissue repair. This study aimed to evaluate the effects of a postbiotic supplement (PS)—composed of inactivated strains of Escherichia coli, Lacticaseibacillus rhamnosus, and Lactiplantibacillus plantarum—on fibroblast function, particularly in the context of bacterial secretomes from common pathogenic strains. Methods: Human fibroblast cell lines (HFF-1 and CCD-18Co) were treated with cell-free supernatants (CFS) from E. coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212, either alone or in combination with the PS. Assessments included cell count, migration (via scratch assay), oxidative stress levels, and expression of immune-related genes (IL-6, IL-10, TNF-α, DRD4). Results: CFS from E. faecalis significantly increased fibroblast counts, whereas E. coli and S. aureus CFS reduced cell counts and elevated oxidative stress. Co-treatment with PS reversed these effects in a strain-dependent manner by lowering oxidative stress and partially restoring cell proliferation. Scratch assays demonstrated enhanced migration in PS-treated fibroblasts. Gene expression analyses revealed no statistically significant changes, though variable trends were observed across treatment groups. Conclusions: PS may mitigate the harmful effects of certain bacterial secretomes while preserving or enhancing beneficial ones. Its ability to reduce oxidative stress and promote fibroblast proliferation and migration suggests a potential pro-regenerative role in vitro. Although gene expression changes were limited, the results offer initial insights into the underlying molecular responses influenced by postbiotic supplementation. Full article