Search Results (1,592)

Akkermansia muciniphila, a next-generation probiotic in the human intestinal mucus layer, exhibits significant health-promoting properties. However, traditional static culture systems fail to replicate the dynamic peristaltic environment of the gastrointestinal tract, limiting understanding of its metabolic characteristics. This study employed an improved gastrointestinal bioreactor simulating intestinal peristalsis to investigate A. muciniphila growth dynamics and metabolomic profiles under dynamic conditions. Dynamic cultivation significantly enhanced bacterial growth. Biomass reached 1.32 ± 0.03 g/L in bovine heart infusion (BHI) medium and 2.03 ± 0.05 g/L in BHI supplemented with 2.5 g/L porcine mucin. These values represent increases of 45.05% and 123.08% relative to static BHI cultures, respectively. Dynamic conditions markedly elevated short-chain fatty acid production (acetic, propionic, isobutyric, isovaleric acids). Untargeted metabolomics identified 1463 metabolites with 1294 showing significant differential expression. Dynamic cultivation substantially altered amino acid biosynthesis, fatty acid, purine, and pyrimidine metabolism. These findings advance the understanding of A. muciniphila physiology and provide insights into its metabolic characteristics under simulated intestinal conditions. Full article

Metabolic diseases are strongly associated with chronic systemic inflammation and oxidative stress, which disrupt the microbiota–gut–brain (MGB) axis and promote neuroinflammation. Dysbiosis favors the release of proinflammatory metabolites, reactive oxygen species (ROS), and lipopolysaccharides (LPS), increasing intestinal permeability and triggering systemic immune responses that reach the central nervous system (CNS) through a weakened blood–brain barrier (BBB). This review summarizes current knowledge on the pathophysiological mechanisms linking the MGB axis, metabolic disorders, and neuroinflammation, as well as the therapeutic potential of antioxidants. A literature search was conducted in PubMed, Web of Science, Scopus, and ScienceDirect and included original research articles, reviews, clinical trials, and meta-analyses related to microbiota, neuroinflammation, oxidative stress, and antioxidant interventions. Evidence indicates that dysbiosis exacerbates metabolic dysfunction by activating the nuclear factor kappa B (NF-κB) and NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathways, while excessive ROS production impairs mitochondrial function, neuronal survival, and cognitive processes. Antioxidant strategies, including polyphenols, omega-3 fatty acids, curcumin, vitamins C and E, and probiotics, can restore microbial diversity, reinforce intestinal and BBB integrity, and modulate oxidative and inflammatory signaling. In conclusion, supplements and bacteria with antioxidant properties show promising therapeutic effects by targeting oxidative stress mechanisms involved in metabolic diseases and their pathological consequences, such as dysbiosis and neuroinflammation. Full article

Fermented foods and probiotics represent complementary yet distinct components of human nutrition. Fermented foods are shaped by biochemical transformations driven by microbial metabolism, whereas probiotics are live microorganisms that may confer health benefits to the host. In both cases, bacteria, yeasts, and filamentous fungi mediate key metabolic activities that generate bioactive compounds and modulate host–microbiota interactions. During fermentation, microbial communities synthesize organic acids, peptides, exopolysaccharides, vitamins, and other metabolites that enhance food safety, sensory attributes, and potential health-promoting properties. Several microbial products, such as bacteriocins, reuterin, hydroxylated fatty acids, and exopolysaccharides, exhibit antimicrobial, immunomodulatory, antioxidant, and cholesterol-lowering activities. Advancing our understanding of microbial metabolism in fermented foods is essential for developing next-generation functional foods and nutraceuticals that leverage microbial biotransformations to support human health. Nonetheless, multiple challenges limit the translation of these advances into commercial products. Inadequately controlled fermentation may introduce microbiological or chemical hazards, regulatory frameworks governing microbial use in foods remain insufficiently defined, and standardized procedures for microbial strain handling and characterization are still lacking. This narrative review integrates current evidence on the nutraceutical properties of fermented foods and probiotics, while also examining the associated safety considerations and the technological factors that influence fermentation processes. Full article

Probiotics are known to improve gut microbiota balance, enhance food digestion, and support overall health. Among these, Bacillus species are particularly promising due to their safety, spore-forming ability, environmental resilience, and diverse enzymatic activities. However, most Bacillus probiotics used in industry are of terrestrial origin, leaving marine-derived strains largely unexplored. Utilising the untapped potential of marine microbial biomass, this study presents a multi-stage methodology for identifying and evaluating marine-derived Bacillus strains with probiotic potential. A structured screening pipeline was applied to 67 microbial isolates from the Great Barrier Reef sponges. Initial selection focused on essential probiotic characteristics, including growth, stability, safety, and survival under gastrointestinal conditions. Strains meeting these criteria were then assessed for desirable properties, including digestive enzyme production and pathogen inhibition. Using this workflow, three marine-derived Bacillus strains were identified as potential probiotics, one of which demonstrated strong antimicrobial activity against Salmonella enterica at 5 and 10 mg/mL (p < 0.01). These findings demonstrate the capability of marine-associated Bacillus as novel bioproducts with functional antimicrobial properties. Full article

Kefir grains are a valuable source of exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) with potential applications in fermented dairy products. In this study, LAB isolated from kefir grains originating from five regions were screened for EPS production and probiotic-related properties. Three strains, Lactiplantibacillus plantarum XZ61, Lactobacillus kefiranofaciens EG10, and Lentilactobacillus kefiri EG12, were selected based on high EPS yield, antimicrobial activity, antioxidant capacity, and tolerance to acidic and bile salt conditions. After optimization, the highest EPS yield (539.57 μg/mL) was obtained from strain EG10.The purified EPS consisted of two molecular weight fractions (≈1.4 and 23~25 kDa) and was rich in mannose (33.38~61.58%). Among the three EPS, EG10-EPS exhibited superior emulsifying and flocculating properties comparable to commercial stabilizers, as well as notable ABTS^•+ and hydroxyl radical scavenging activities. Furthermore, co-fermentation of L. kefiranofaciens EG10 with conventional yogurt starter cultures significantly improved exopolysaccharide content, water-holding capacity, texture, and antioxidant activity of fermented milk, particularly in cow milk. These results demonstrate the potential of kefir-derived EPS-producing LAB as natural functional cultures for fermented dairy applications. Full article

This study investigated the biosynthesis of magnetite nanoparticles mediated by chia mucilage (CM-Fe₃O₄ NPs) and their application in the co-encapsulation of Lactobacillus rhamnosus GG (LGG) using spray drying. CM-Fe₃O₄ NPs were synthesized by combining CM extract with iron salts, in which hydroxyl and carbonyl groups of CM acted as natural ligands for Fe²⁺/Fe³⁺ ions. A response surface design was applied to optimize synthesis parameters, focusing on size distribution and zeta potential, and confirming the influence of pH on colloidal stability. Characterization by FE-SEM, DLS, XRD, UV-Vis, and FTIR revealed spherical particles with an inorganic core (50–300 nm) and a hydrated organic coating (600–900 nm), consistent with a spinel structure functionalized by CM. Spray-drying encapsulation tests showed that incorporating CM-Fe₃O₄ NPs did not compromise bacterial viability, maintaining optimal moisture content and survival. Growth curves and confocal microscopy corroborated the physiological compatibility of the nanoparticles, with no alterations in LGG morphology or growth dynamics. Under simulated gastrointestinal conditions, co-encapsulated microcapsules exhibited slightly improved survival in the gastric phase and significantly greater viability in the initial intestinal phase. These results suggest that CM-Fe₃O₄ NPs modulate matrix degradation and promote controlled release, ensuring therapeutic concentrations of LGG in the intestine. Overall, the CM-Fe₃O₄ nanocomposite system integrates the protective properties of biopolymers with the functional advantages of iron nanoparticles, offering dual functionality: probiotic stabilization and potential iron supplementation. This innovative, food-grade approach supports the development of next-generation functional foods with combined therapeutic and nutritional benefits. Full article

As probiotic microorganisms must remain viable at a certain level throughout the shelf life of fermented foods, various plant-based prebiotics are added to fermented dairy products. Pea (Pisum sativum L.) is a remarkable food source due to its prebiotic properties, high phenolic content and antioxidant capacity. In this study, fermented milks containing different proportions of pea fiber powder (0%, 0.5%, 1%, 1.5% and 2%) were produced using Limosilactobacillus reuteri ACC27, which has probiotic potential, and Streptococcus thermophilus 212S. The addition of pea fiber powder promoted the growth of Limosilactobacillus reuteri ACC27, increasing viable cell counts by approximately 1 log CFU/g compared to the control during storage. In addition, the fermentation time was shortened by approximately 30 min in samples containing pea fiber. Malic (84.07–175.58 mg/kg), lactic (11,670.45–13,791.66 mg/kg), acetic (145.12–240.53 mg/kg) and benzoic acids (17.07–20.34 mg/kg) were detected in all samples. Furthermore, pea fiber supplementation improved physicochemical properties by reducing syneresis and modifying water release behavior, while also increasing viscosity. The addition of pea fiber also enhanced total phenolic content and antioxidant capacity of the samples. The results of the principal component analysis revealed that the addition of pea fiber powder was associated with potentially improved functional attributes and enhanced probiotic viability under the studied conditions. Full article

Lactiplantibacillus plantarum LP28 (LP28), isolated from traditional Taiwanese dried tofu, has been demonstrated to have substantial probiotic potential because it increases the production of short-chain fatty acids (SCFAs) and strengthens anti-inflammatory responses. In this study, the safety of LP28 was assessed using both in vitro and in vivo approaches, including whole-genome sequence analysis, the Ames bacterial reverse mutation assay, a chromosomal aberration test, a rodent peripheral blood micronucleus test, a 28-day subacute oral toxicity assay, and an assessment of hemolytic activity. In vitro phenotypic evaluation revealed that LP28 exhibited no hemolytic activity and was susceptible to all the tested antibiotics except kanamycin. In vivo assessments revealed no significant alterations in reticulocyte counts or micronuclei incidence in ICR mice, and SD rats exhibited no subacute toxicity at an oral LP28 dosage of 2000 mg/kg body weight/day for 28 days. Moreover, a whole-genome sequence analysis of LP28 revealed the absence of antimicrobial resistance genes, harmful virulence factors, and genes associated with biogenic amine synthesis. Additionally, the presence of genes involved in stress responses (e.g., acid, bile salt, heat, osmotic, and oxidative stresses) and adhesion-related genes was confirmed. Furthermore, LP28 contains six genes (plnA, plnE, plnF, plnJ, plnK, and plnN) that encode bacteriocin precursor peptides, suggesting the potential for enhanced probiotic effects through the production of antimicrobial plantaricins. These findings highlight the potential of LP28 as a safe and effective probiotic for human consumption. Full article

Background/Objectives: Atopic dermatitis (AD) is associated with gut dysbiosis linked to early-life antibiotic use and Staphylococcus aureus colonization. Gum Arabic (GA), a prebiotic, may modulate this dysbiosis and influence AD-related microbial balance. This study evaluated whether GA could support AD-associated probiotics-Lactobacillus casei, Bifidobacterium bifidum, and Bifidobacterium infantis-under amoxicillin- or azithromycin-containing conditions, examined the response of S. aureus under the same screening conditions, and developed GA-phospholipid-based semisolid carriers for topical application. Methods: Probiotic strains were cultured with 1–5% GA in the presence and absence of antibiotics, and viable cell counts were assessed. Sixteen topical formulations containing propylene glycol or isopropyl myristate in a hydrogenated phosphatidylcholine base were prepared and screened for rheological properties and galactose release using in vitro release testing (IVRT) and HPLC-UV. Results: GA at 1–2% concentrations promoted probiotic growth in antibiotic-free conditions. GA preserved B. infantis viability under azithromycin exposure in this in vitro screening model. For S. aureus, numerical CFU differences were observed between antibiotic-only and GA-containing conditions; however, the present screening design was not intended to determine antibiotic interaction outcomes. Formulations F14 (2% GA + 7% IPM) and F15 (3% GA + 7% IPM) exhibited optimal spreadability. IVRT showed that 6 h cumulative galactose release varied by formulation (F6 > F10 > F14 > F15). Conclusions: GA demonstrated dose-dependent prebiotic activity and preserved B. infantis viability under azithromycin exposure in this in vitro screening model. For S. aureus, the observed CFU differences between antibiotic-only and GA-containing conditions should be considered exploratory only and do not allow for conclusions regarding interference with antibiotic efficacy. Optimized GA-HPC systems with suitable rheological and release characteristics represent promising candidates for further preclinical investigation. Full article

In the post-antibiotic era, the Bacillus-based direct-fed beneficial microorganisms are emerging as a cornerstone for sustainable animal farming. This study aimed to screen and evaluate Bacillus strains with probiotic potential for use as feed additives. A total of 394 Bacillus strains were initially screened based on their extracellular enzyme production (cellulase, protease, and amylase) and antibacterial activities against Escherichia coli, Staphylococcus aureus, and Salmonella enterica. Two strains, Bacillus velezensis FJAT-10508 and FJAT-13563, were selected and subsequently subjected to in vitro probiotic characterization, safety assessment, and whole-genome analysis. The results demonstrated that both strains exhibited α-hemolysis, acceptable antibiotic susceptibility profiles, absence of invasion and cytotoxicity effect on the Caco-2 cells, and no mobile virulence or antibiotic resistance genes, indicating their safety as probiotic candidates. High endospore-forming efficiencies (72.4–90.8%), strong auto-aggregation (74–85%) and co-aggregation abilities (52–82%) were observed. In addition, both strains showed considerable tolerance to simulated gastrointestinal conditions, with vegetative cell and endospore survival rates of 28.33–38.33% and 85–89.67% at pH 2.0, and 38.33–43.33% and 90.33–96.33% in 0.3% bile salts, respectively. Overall, B. velezensis FJAT-10508 and FJAT-13563 demonstrated robust in vitro probiotic properties, supporting their potential application as reliable Bacillus-based feed additives. Full article

Kombucha is a fermented beverage produced using a symbiotic consortium of acetic acid bacteria and yeasts, often marketed for its health-promoting properties. However, probiotic bacteria in kombucha are typically present at inconsistent levels and may not remain viable during fermentation. In this study, three Lactobacillus strains (Lacticaseibacillus rhamnosus ATCC 53103 (L. rhamnosus), Lactiplantibacillus plantarum subsp. plantarum ATCC 14917 (L. plantarum) and Lentilactobacillus hilgardii (L. hilgardii) isolate) were encapsulated in whey protein using the lyophilization method and added individually at the start of kombucha fermentation. Lactic acid bacteria (LAB)–enriched kombucha samples were evaluated for chemical composition (polyphenols, flavonoids, vitamin C and organic acids) and functional properties (antimicrobial, antiproliferative, antioxidant and anti-inflammatory activities) and compared to a traditionally obtained control kombucha, primarily demonstrating in vitro and experimental assessment. Encapsulation maintained LAB viability above 6–7 log CFU/mL throughout fermentation, producing kombucha with enhanced microbial stability. LAB–enriched samples exhibited increased L-lactic acid and antimicrobial activity. L. rhamnosus and L. hilgardii–enriched samples exhibited increased antiproliferative and anti-inflammatory activities, which may be associated with strain-dependent production of organic acids, polyphenol modulation and LAB-derived bioactive metabolites. Antioxidant activity varied depending on assay, and L. rhamnosus–enriched kombucha showed higher anti-inflammatory activity. These findings demonstrate that whey protein encapsulation can preserve LAB during fermentation, enhance specific bioactive properties and provide a platform for developing functional kombucha beverages with potential applications in the food industry. Full article

The diverse health benefits of lactic acid bacteria (LAB) have made them a focal point of research in the fields of food and health sciences. Furthermore, probiotics and postbiotics have been demonstrated to directly or indirectly influence food quality and human health. A substantial body of research has been dedicated to the antimicrobial activity of pro- and postbiotics; however, their antioxidant properties remain relatively unexplored. Although LAB are facultative anaerobes, there are several species that have the potential to undergo aerobic respiration, thereby being exposed to the action of reactive oxygen species (ROS). The resultant oxidative stress has been shown to damage all intracellular molecules, thus requiring the presence of antioxidants in order to counteract this effect. The present review discusses the peculiarities of respiration, the role of ROS, the antioxidant potential of LAB, and the mechanisms underlying their activity. Furthermore, the study explores the antioxidant capacity of probiotics and postbiotics, as well as their role in controlling oxidative stress. The objective of the present review is to provide an overview of the current research on the oxidative stress tolerance and antioxidant capacity of LAB and its impact on food. Full article

Enterococcus spp. are common but not predominant commensal bacteria that inhabit the gastrointestinal tracts of humans and animals and are widely distributed in various environmental matrices and diverse food sources. Multiple strains of beneficial enterococci are increasingly utilized as protective cultures, alternatives to antibiotics, and probiotics for controlling pathogens, mitigating disease, modulating the microbiome, and supporting overall host health. They also support food fermentation and safety, enhance sensory properties, and produce bioactive compounds such as bacteriocins with strong pathogen-inhibitory activity and multifarious health benefits. Despite their advantages in health and agrifood systems, their association with healthcare-associated infections and the spread of antimicrobial resistance raises concerns about their safety. These risks underscore the need for stringent safety evaluations before their use as probiotics, alternatives to antibiotics, or protective cultures. Here, we provide a comprehensive atlas of the multifaceted probiotic and antimicrobial potential, as well as safety considerations of beneficial enterococci. This would provide a valuable resource for future research, regulatory assessments, and applications in the agrifood system and healthcare. Full article

Water kefir is a non-dairy fermented beverage that has received increasing scientific attention due to its complex microbial composition and its suitability for individuals with dietary restrictions. This review critically examines the current body of scientific evidence addressing the functional properties and potential health-related effects of water kefir. A systematic literature search was conducted using the PubMed and Scopus databases, focusing on studies published over the past decade. Experimental evidence derived from in vitro assays and in vivo studies in animal models suggests that water kefir and its derived components may exhibit antioxidant, anti-inflammatory, antibacterial, detoxifying, and gut microbiota-modulating activities. Several studies have also reported probiotic-related characteristics among microorganisms isolated from water kefir, as well as beneficial effects in experimental models of chronic conditions, including type 2 diabetes, colitis, and liver injury. Reported microbiota-associated effects include increased bacterial diversity, enrichment of beneficial genera such as Lactobacillus spp. and Bifidobacterium spp., and reductions in potentially pathogenic taxa including Escherichia spp. and Shigella spp. Nevertheless, the available evidence is largely preclinical, and substantial variability in microbial composition, fermentation conditions, and experimental design limits direct comparison across studies. Well-designed human clinical trials are therefore required to validate these findings, establish efficacy and safety, and clarify the relevance of water kefir as a functional fermented food in human health. Full article

Alternative substrates to traditional Camellia sinensis tea are increasingly investigated to diversify kombucha and enhance its functional properties. This review synthesizes evidence (2020–2025) on how non-tea substrates influence microbial ecology, metabolite composition, and bioactivity of kombucha. A semi-systematic search of PubMed, Scopus, Web of Science, and publisher platforms identified studies on fruit, vegetable, herbal, algal, cereal, dairy, and food-industry by-product substrates reporting compositional or functional outcomes. Extracted data included substrate characteristics, fermentation conditions, SCOBY features, analytical methods, and reported antioxidant, anti-inflammatory, metabolic, probiotic, and dermatological effects. Fermentation often leads to an increase in total phenolic content and antioxidant capacity. These effects are highly dependent on fermentation conditions, particularly duration and substrate composition. In some cases, prolonged fermentation may result in phenolic degradation or transformation, leading to reduced levels of certain compounds. Fruit- and hibiscus-based systems enhanced anthocyanin-driven antioxidant and anti-inflammatory activity. Vegetable and cereal substrates supplied phenolic acids and β-glucans associated with metabolic regulation and gut health, whereas by-products and algal fermentations supported waste valorization and enrichment in chlorogenic acids, pigments, fibers, and peptides. Despite promising functionality, substantial inter-study variability and limited in vivo validation and the lack of standardized fermentation protocols constrain translational application. In addition, the inherent variability in SCOBY microbial composition represents a major source of inconsistency, as differences in microbial communities can significantly influence fermentation dynamics, metabolite profiles, and functional outcomes. Full article