Lactic Acid Bacteria as Antimicrobial Agents: Food Safety and Microbial Food Spoilage Prevention

In vitro effects of crocin on the possible anticancer properties of Lactococcus lactis against colorectal adenocarcinoma cells

Probiotics have been suggested to contribute to cancer prevention through various mechanisms. Additionally, recent studies have established a connection between diet, microbiota, and overall health. In this respect, the current study aims to understand the impact of crocin on possible anti-cancer and antibacterial effects of Lactococcus lactis (L. lactis) in colorectal cancer cells and pathogenic bacteria. The study involved collecting cell-free supernatants (CFSs) from untreated bacteria as a control group and bacteria treated with crocin, and then examining their ability to prevent the growth of HCT-116 colon cancer cells. It was demonstrated that L. lactis, when treated with crocin, can effectively combat against various types of pathogenic bacteria and can survive in acidic conditions. Both CFS and cro-CFS exhibited a dose-dependent inhibition of HCT-116 cell growth but crocin-treated bacteria showed more significant effects. The half-maximal inhibitory concentration (IC50) for cell growth inhibition was 97.41 µL/mL in CSF group and 72.07 µL/mL in cro-CFS group. The results of flow cytometry tests confirmed the MTT assay findings, showing that cro-CFS group had a significantly higher rate of apoptosis compared to CFS of control group. The results obtained from qPCR also showed that the Caspase 9 and BAX genes were upregulated, and the BCL-2 expression level was reduced in cells treated with cro-CFS compared to the CFS group. Overall, these findings suggest that crocin may alter the composition of CFS from probiotics that are present in the gut, potentially impacting their ability to combat cancer.

Food, Health, and Environmental Impact of Lactic Acid Bacteria: The Superbacteria for Posterity

Lactic acid bacteria (LAB) are Gram-positive cocci or rods that do not produce spores or respire. Their primary function is to ferment carbohydrates and produce lactic acid. The two primary forms of LAB that are currently recognized are homofermentative and heterofermentative. This review discusses the evolutionary diversity and the biochemical and biophysical conditions required by LAB for their metabolism. Next, it concentrates on the applications of these bacteria in gut health, cancer prevention, and overall well-being and food systems. There are numerous uses for LAB, including the food and dairy sectors, as probiotics to improve human and animal gut-health, as anti-carcinogenic agents, and in food safety as biopreservatives, pathogen inhibitors, and reducers of anti-nutrients in foods. The group included many genera, including Aerococcus, Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Streptococcus, Tetragenococcus, Vagococcus, and Weissella. Numerous species of Lactobacillus and Bifidobacterium genera as well as other microbes have been suggested as probiotic strains, or live microorganisms added to meals to improve health. LAB can colonize the intestine and take part in the host's physiological processes. This review briefly highlights the role of these bacteria in food safety and security as well as aspects of regulation and consumer acceptance. Finally, the recent innovations in LAB fermentations and the limitations and challenges of the applications of LAB in the food industry are discussed. Notwithstanding recent developments, the study of LAB and their functional components is still an emerging topic of study that has not yet realized its full potential.

Incorporation of probiotics in post-harvest wash treatments reduces Salmonella contamination and improves egg safety

Salmonella Enteritidis (SE) is a prevalent foodborne pathogen that is commonly transmitted through contaminated shell eggs. Therefore, decontamination of eggs is critical to food safety. Hence, this study determined the efficacy of incorporating probiotics in wash water to promote egg safety. Fresh eggs inoculated with a five-strain mix of SE (∼9 log CFU/egg) were washed using either a dip or spray method with one of the following treatments: Lactobacillus rhamnosus NRRL-B-442 (LR; ∼10 log CFU/ml), L. paracasei DUP 13076 (LP; ∼10 log CFU/ml), Hafnia alvei (HA; ∼10 log CFU/ml), chlorine (200 ppm), or tap water (Control). Eggs were sampled for surviving SE and probiotic populations immediately following wash and during refrigerated storage for 21 days. Three independent trials were conducted in a completely randomized design, and data were analyzed using GraphPad (Version 9.3.1) with significance set at P ≤ 0.05. Both dip and spray application of probiotics significantly reduced SE populations on eggshells and within internal contents throughout refrigerated storage (p ≤ 0.05). On the external surface SE populations in LP and LR groups were reduced to ∼4 log CFU/egg and ∼2 log CFU/egg on days 7 and 14 respectively, while ∼5.6 log CFU/egg and ∼4.8 log CFU/egg were still recovered from control and chlorine-treated samples. Similarly, only 10 % of probiotic-treated samples tested positive for SE in internal contents as opposed to 30-40 % positivity in the control and chlorine-treated samples. Overall, probiotic application by spraying or dipping significantly reduced SE populations on eggs (P ≤ 0.05) without impacting egg quality parameters including Haugh units and egg grade (P > 0.05). Although both washing modalities were effective, reduced water usage makes the spray method more environmentally friendly. Overall, incorporation of probiotics in wash water can be a safe, effective, and organic-friendly antimicrobial strategy to promote egg safety.

Formulation and evaluation of probiotic starter culture: impact on Ethiopian cottage cheese "Ayib" safety, stability, sensory acceptability and antioxidant potential

BACKGROUND

Ayib is a traditionally processed dairy product in Ethiopia that demonstrates significant variability in shelf life, sensory attributes, and safety, primarily own to the spontaneous fermentation of milk and differing household practices. This study aimed to develop mixed probiotic starter cultures from top seven previously isolated lactic acid bacteria to achieve a synergistic effect on sensory qualities consistent, enhanced safety, extended storage stability, and antioxidant potential.

METHODS

Nine mixed starter cultures were formulated using seven lactic acid strains that are known for their superior fermentation and probiotic capabilities. Pasteurized milk was inoculated with 5% of each starter culture and incubated at 37 ± 2 °C for 8 h. Fermented milk was then defatted by shaking at 100 rpm for 1 h. Following fat removal, buttermilk was heated to 50-60 °C for 40-50 min to facilitate curd (Ayib) formation. After cooling, the curd was separated from whey. A 200-g portion of the curd was wrapped in sterile cheesecloth and immersed in pasteurized whey inoculated with 8 log CFU/mL of the formulated starter cultures for 30 min before being re-drained for 1 h.

RESULTS

The physicochemical properties, consumer acceptability, and storage stability of the resulting products were evaluated, revealing total solids ranging from 20.67 to 22.89%, pH values between 3.89 and 4.49, and titratable acidity ranging from 0.63 to 0.93%. Sensory evaluation, conducted using a five-point hedonic scale, showed overall acceptability scores ranging from 3.31 for Ayib treated with (F9) to 4.03 for Ayib treated with (F2). Remarkably, the storage stability of the treated Ayib was enhanced by 2-9 times compared to the control sample. The antioxidant analysis demonstrated that among the isolates, the Lactobacillus curvatus (NZ-44) exhibited the highest individual antioxidant activity of 57.77%. Furthermore, the formulated mixtures, particularly (F6), displayed synergistically enhanced antioxidant activity of 99.27%.

CONCLUSIONS

These findings suggest that lactic acid bacteria strains can improve the nutritional value, safety, and storage stability of fermented dairy products, such as Ayib, with potential applications in both the food and pharmaceutical industries.

Influence of Silver Doping and Anodization Current Density on Aluminum Surface Properties and Surface Adhesion of Staphylococcus aureus and Escherichia coli

In this study, we investigated the influence of crystal structure, topography, and elemental composition of aluminum oxide surfaces on bacterial adhesion. The structural properties of the surfaces were systematically controlled by varying the current density (1.5, 2.0, and 2.5 A/dm2) and silver doping during the anodization process. The resulting changes in structural and morphological properties were examined by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), contact angle measurements, and profilometry. Using FE-SEM analysis, we evaluated the adhesion of model bacteria, Escherichia coli and Staphylococcus aureus, to surfaces exhibiting diverse morphologies and elemental compositions. The surface roughness and crystal size of the aluminum oxide increased proportionally with the applied current density and silver doping. According to the XRD results, the slip plane crystal structure of (311) increased proportionally to the current density but decreased with silver doping. Specifically, while stepped atomic alignment of (311) planes facilitates bacterial attachment, smoother (200) planes reduce the adhered bacteria population. Further analysis via XPS revealed that the oxide crystal structure of undoped surfaces shifted from the tetrahedral to octahedral form with increasing current density, while silver-doped surfaces exhibited the opposite trend. Additionally, increasing current density during the preparation of silver-doped surfaces diminished the ratio of ionic silver to metallic silver, suggesting a lowered propensity for bacterial adhesion. S. aureus adhesion to undoped surfaces increased 4.46-fold for surfaces prepared at 2.5 A/dm2 compared to that at 1.5 A/dm2. Moreover, E. coli adhesion was completely inhibited on silver-doped surfaces anodized at 1.5 A/dm2. Reducing the surface roughness and incorporating silver during the anodization of aluminum surfaces decrease the number of bacteria adhering to aluminum oxide surfaces.

Antibiofilm properties of lactic acid bacteria and their metabolites against Salmonella enterica serotype Enteritidis on eggshell surface

Salmonella enteritidis (SE) is a pathogenic bacterium commonly found on the surface of eggshells. In this study, we investigated the biofilm formation of a specific strain of S. enteritidis, CIDCA 115 (SE 115) on eggshells. Additionally, we examined the impact of Lentilactobacillus kefiri strains 83113 and 8321, as well as Lactiplantibacillus plantarum 83114, and their metabolites present in the supernatant on the biofilm formation of SE 115. Scanning electron microscopy revealed that SE 115 formed a mature biofilm structure on the eggshell. During co-incubation and pre-incubation, lactic acid bacteria strains significantly reduced the formation of SE 115 biofilm (p < 0.05 and p < 0.01, respectively) compared to SE 115 grown alone. The cell-free supernatants of lactic acid bacteria also exhibited a reduction in SE 115 biofilm formation and modified its structure. Co-incubation with SE 115 induced alterations in the composition of biofilm matrix components, notably in the levels of fimbria curli and cellulose. The qPCR analysis revealed that, after 48 h of incubation, the expression of the csgD gene, a critical regulator of biofilm formation, remained unchanged compared to planktonic cells. However, genes associated with the production of biofilm matrix components, curli (csgA) and cellulose (bcsA), exhibited heightened expression in the presence of lactic acid bacteria compared to the planktonic state. This study highlights the potential of lactic acid bacteria strains and their metabolites as innovative strategies for managing Salmonella biofilm formation in the context of poultry production.

Effect of marination with bioprotective culture-containing marinade on Salmonella spp. and Listeria monocytogenes in chicken breast meat

This study investigated the survival of Pseudomonas spp., Salmonella spp., and Listeria monocytogenes in chicken breast meat marinated with a marinade containing bioprotective lactic acid bacteria (Latilactobacillus curvatus, Latilactobacillus sakei, and Lactiplantibacillus plantarum) during storage at 4°C and 8°C. In the first phase, a natural, chemical-free marinade (pH 3.6) was evaluated over 7 days. In this marinade, Pseudomonas spp. did not survive, Salmonella spp. were inactivated within 7 days, L. monocytogenes counts showed negligible reduction, and bioprotective cultures remained stable. In the second phase, chicken breast meat contaminated with Salmonella spp. and L. monocytogenes was divided into control (non-marinated), marinated control (M-C), and marinated with a marinade containing mixture of bioprotective cultures (M-PC). Initial pH values were 5.99 (control), 5.24 (M-C), and 5.32 (M-PC). At 4°C, L. monocytogenes counts in the M-PC group were 4.4 log10 cfu/g lower than the control and 1.4 log10 cfu/g lower than the M-C group on Day 14 (p < 0.05). By Day 14, Pseudomonas spp. counts were 9.4, 7.3, and 5.7 log10 cfu/g in the control, M-C, and M - PC groups, respectively (p < 0.05). At 8°C, Salmonella spp. in the M-PC group fell below 1.0 log10 cfu/g by Day 12, and L. monocytogenes counts were significantly lower than in the M-C group (p < 0.05). Marinating with bioprotective cultures enhanced microbial safety and extended shelf life compared to marinating without them. This approach could offer significant potential for improving the preservation and safety of poultry products. PRACTICAL APPLICATION: Marinated poultry meat, whether prepared domestically by consumers or commercially produced by the poultry meat industry, is widely enjoyed for its flavor and convenience. In this study, bioprotective cultures were incorporated into the marinade as an alternative to chemical preservatives. The findings demonstrate that marinating chicken breast meat with a marinade composed entirely of natural ingredients and enriched with bioprotective cultures not only extends the product's shelf life but also significantly limits the survival of Pseudomonas spp., Salmonella spp. and Listeria monocytogenes. These results suggest that meat products marinated with bioprotective cultures, or ready-to-use marinades containing such cultures, can be effectively developed and marketed by the meat industry to meet consumer demand for safer, long-lasting, and naturally preserved food products.

Novel colored hydroxypropyl methyl cellulose/ magnetite carbon dots films for beef packaging with DFT calculations and molecular docking study

This study investigates the preparation and characterization of a novel HPMC-MCDs (Hydroxypropyl methylcellulose-magnetite carbon dots) composite film for potential applications in food safety monitoring. While carbon dots (CDs) offer promising sensing capabilities, their inherent lack of color limits direct visual detection, a limitation addressed in this work by incorporating magnetite (Fe3O4) to create a visually discernible sensor. Characterization techniques, including XRD, FTIR, and SEM, confirmed the successful integration of MCDs within the HPMC matrix. The incorporation of MCDs significantly reduced the film's surface roughness. The HPMC-MCDs composite exhibited a remarkably smooth surface. DFT calculations revealed enhanced stability of the HPMC-MCDs composite. Fluorescence studies demonstrated color change in the HPMC-MCDs upon interaction with Salmonella enterica and B. cereus, suggesting potential for bacterial detection. Furthermore, the HPMC-MCDs film exhibited pH-sensitive behavior, changing color in response to pH variations, making it a promising candidate for visual monitoring of beef meat spoilage. These findings suggest that HPMC-MCDs have the potential to serve as a multifunctional sensing platform for food safety applications.

Use of Selected Environmental Lactic Acid Bacteria During Industrial Production of Heat-Treated Nitrite-Free Organic Sausage

This study aimed to evaluate the potential of lactic acid bacteria (LAB) isolated from organic acid whey as an alternative to nitrites in heat-treated organic sausages. Eleven LAB strains were screened for their ability to develop sensory characteristics similar to traditionally cured meat. Based on the results, Lactiplantibacillus plantarum S21 was selected for further experiments. Four sausage treatments were produced: control cured (C), salted (S), salted with L. plantarum S21 at 107 CFU/g (LP), and salted with acid whey (AW). The pH value, oxidation-reduction potential (ORP), antioxidant activity of peptides (ABTS•+), thiobarbituric acid-reactive substance (TBARS), fatty acid profile, and microbiological quality were assessed post-production and after 14 days of cold storage. After production, the LP and AW sausages had a lower pH than the cured (C) and uncured (S) control samples. LP sausages exhibited a stable pink colour due to myoglobin conversion to nitrosylmyoglobin, comparable to the cured control. The LP sausages were similar in overall sensory quality to the cured (C) samples and were superior to the S and AW sausages after storage. The lowest ORP value was observed in treatment C after production, whereas after storage, no significant differences were found between the treatments. The highest antioxidant activity of peptides was observed in the LP sausages. It was shown that the LP and AW treatments had lower saturated fatty acid content and higher monounsaturated and polyunsaturated fatty acid content than the C and S treatments. Nevertheless, the C treatment had the lowest TBARS value. Lower total viable counts were found in the C and LP treatments than in the S and AW treatments after storage. Our research demonstrates the potential of L. plantarum S21 for producing heat-treated sausages without nitrites, assuming the implementation of additional anti-botulinum barriers. Nevertheless, further studies on the role of bacteria in meat oxidation processes are needed.

A Meta-Analysis on the In Vitro Antagonistic Effects of Lactic Acid Bacteria from Dairy Products on Foodborne Pathogens

Raw milk and traditional fermented foods such as artisanal cheese represent a natural source of lactic acid bacteria (LAB). They can produce antimicrobial compounds, such as bacteriocins and lactic acid, which may be exploited in dairy biopreservation. This study aimed to conduct a systematic review and meta-analysis to synthesize the inhibition diameter (ID) of LAB against L. monocytogenes, S. aureus, and Salmonella spp. Literature electronic searches were performed on PubMed, Scopus, and Web of Science, to identify articles that reported data on in-vitro antimicrobial activity by LAB isolated from dairy foods. A total of 1665 papers were retrieved, and 20 primary studies were selected according to the selection criteria, of which 397 observations were extracted. Random-effects meta-regression models were employed to describe the effects of LAB genus, pathogen concentration, susceptibility method, incubation time, inoculation volume, agar type and pH on the IDs for L. monocytogens, S. aureus, and Salmonella spp. L. monocytogens was the most susceptible pathogen (p < 0.05) to the LAB effects, followed by S. aureus and Salmonella spp. As a whole, LAB from the Lacticaseibacillus genus were the most effective (p < 0.05) in inhibiting L. monocytogens (21.49 ± 2.654 mm), followed by S. aureus (21.06 ± 2.056 mm). Salmonella spp. presented higher (p < 0.05) susceptibility to Lactobacillus genus (19.93 ± 2.456 mm). From the results, a general trend could be observed for the well-diffusion method to produce higher (p < 0.05) ID estimates than the spot and disk methods (30.73 ± 2.530 mm vs. 21.98 ± 1.309 mm vs. 13.39 ± 1.403 mm for L. monocytogenes; 22.37 ± 1.073 mm vs. 14.91 ± 2.312 mm vs. 20.30 ± 2.319 mm for Salmonella spp.), respectively. Among the tested moderators, the pathogen's inoculum concentration, the in vitro susceptibility assay itself, incubation time and inoculation volume on agar are determinant parameters to be looked at when designing a robust and reproducible experimental plan. The in vitro results reinforced that LAB can be useful in controlling the development of pathogenic bacteria frequently found in the dairy industry.

Harnessing the Power of Bacteriocins: A Comprehensive Review on Sources, Mechanisms, and Applications in Food Preservation and Safety

The Sustainable Development Goals (SDGs) emphasize the importance of food safety, prolonged shelf life, and reduced food waste, all of which rely on effective food preservation methods. Bacteriocins, natural antimicrobial substances produced by lactic acid bacteria (LAB), have potential applications in food preservation. This review highlights the role of LAB-derived bacteriocins in preserving food. Bacteriocins are highly effective against foodborne infections because they target cell membranes, break down enzymes, and interfere with cellular activities. The following study used molecular docking to understand the interaction of bacteriocins and their mode of action. With their natural origin and specific action, bacteriocins offer a promising strategy for preventing foodborne diseases and extending shelf life without impacting sensory characteristics. However, challenges such as stable manufacturing, regulatory hurdles, and cost effectiveness hinder the wide adoption of bacteriocins. Nevertheless, LAB-derived bacteriocins offer a safe and efficient approach to improving food preservation, enhancing food safety, and reducing reliance on artificial preservatives. Moreover, immobilized bacteriocins have the potential to be integrated into antimicrobial packaging films, providing a targeted way to reduce the risk of foodborne pathogen contamination and improve food safety. Exploring novel bacteriocins presents exciting opportunities for advancing food preservation and safety. The present study also highlights recent advancements in food preservation through bacteriocins.

Treatment with Lactobacillus paracasei L30 extract induces osteogenic differentiation of human bone marrow mesenchymal stem cells in vitro

Bone-related diseases such as osteoporosis pose a significant health economic burden to countries around the world and, because current treatments are insufficient, more effective therapies are desperately needed. This study explored the potential of Lactobacillus paracasei L30 extract to influence the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBM-MSCs). Our results showed that L30 extract significantly enhanced the expression of osteogenic markers in hBM-MSCs, including alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), and collagen type I alpha 1 (COL1A1). Mechanistic studies revealed that L30 extract activated the p38 MAPK and AKT signaling pathways, leading to phosphorylation of Glycogen synthase kinase-3 beta (GSK3β) and subsequent nuclear translocation of β-catenin. Conversely, inhibition of p38 MAPK, AKT, or knockdown of β-catenin significantly attenuated the osteogenic effects of L30 extract on hBM-MSCs. Furthermore, we found that L30 extract promoted osteogenic differentiation in primary osteoblast precursors isolated from mouse calvaria and enhances bone formation in ex vivo calvarial organ cultures. Therefore, the application of Lactobacillus paracasei L30 extract in such contexts could serve as a therapeutic approach for promoting bone formation. Collectively, our findings suggest a novel approach for the clinical management of bone-related disorders, with possible applications for treating diseases such as osteoporosis.

Fabrication and Characterization of Pectin-Chitosan Edible Coatings with a Cosmos caudatus Leaf Extract for Tomato Preservation

An edible coating based on pectin-chitosan and Cosmos caudatus leaf extract has been created. Cosmos caudatus leaf extract, which contains several bioactive compounds, aims to produce an edible coating with antibacterial properties. C. caudatus extract was incorporated at concentrations of 1, 2, and 3 g into a mixture of 1.5 g of pectin and 1 g of chitosan. The edible coating was applied to the tomatoes using the dipping method. The coated tomatoes were analyzed for 21 days at room temperature to determine the weight loss value. The edible coating was characterized, including FTIR analysis, X-ray diffraction, surface morphology, thermal stability, viscosity, and antibacterial activity. The research results reveal that C. caudatus extract contains anthocyanins with antibacterial properties, has an amorphous crystalline structure, and has a textured surface with partial aggregation. Thermal stability analysis using differential scanning calorimetry (DSC) shows a decrease in thermogravimetric (TG) values with increasing extract concentration. The optimal weight loss (6.18%) was found in the pectin-chitosan composition containing 3 g of C. caudatus extract. At this concentration, the inhibition zones against Escherichia coli and Staphylococcus aureus were 16.4 and 15.6 mm, respectively. These findings indicate that the C. caudatus leaf extract, particularly at 3 g, enhances the antibacterial properties of the edible pectin-chitosan coating, demonstrating its potential to extend the shelf life of tomatoes safely.

Probing the Limits of Reactant Concentration and Volume in Primitive Polyphenyllactate Synthesis and Microdroplet Assembly Processes

Polyester microdroplets have been investigated as primitive protocell models that can exhibit relevant primitive functions such as biomolecule segregation, coalescence, and salt uptake. Such microdroplets assemble after dehydration synthesis of alpha-hydroxy acid (αHA) monomers, commonly available on early Earth, via heating at mild temperatures, followed by rehydration in aqueous media. αHAs, in particular, are also ubiquitous in biology, participating in a variety of biochemical processes such as metabolism, suggesting the possible strong link between primitive and modern αHA-based processes. Although some primitive αHA polymerization conditions have been probed previously, including monomer chirality and reaction temperature, relevant factors pertaining to early Earth's local environmental conditions that would likely affect primitive αHA polymerization are yet to be fully investigated. Hence, probing the entire breadth of possible conditions that could promote primitive αHA polymerization is required to understand the plausibility of polyester microdroplet assembly on early Earth at the origin of life. In particular, there are numerous aqueous environments available on early Earth that could have resulted in varying volumes and concentrations of αHA accumulation, which would have affected subsequent αHA polymerization reactions. Similarly, there were likely varying levels of salt in the various aqueous prebiotic solutions, such as in the ocean, lakes, and small pools, that may have affected primitive reactions. Here, we probe the limits of the dehydration synthesis and subsequent membraneless microdroplet (MMD) assembly of phenyllactic acid (PA), a well-studied αHA relevant to both biology and prebiotic chemistry, with respect to reactant concentration and volume and salinity through mass spectrometry- and microscopy-based observations. Our study showed that polymerization and subsequent microdroplet assembly of PA appear robust even at low reactant concentrations, smaller volumes, and higher salinities than those previously tested. This indicates that PA-polyester and its microdroplets are very much viable under a wide variety of conditions, thus more likely participating in prebiotic chemistries at the origins of life.

From probiotic fermentation to functional drinks: a review on fruit juices with lactic acid bacteria and prebiotics

In recent years, the demand for probiotic beverages has surged, with dairy products traditionally serving as the primary sources of probiotics. However, many consumers face health issues such as lactose intolerance, milk allergies, and high cholesterol, which prevent them from consuming dairy products. This has led to the exploration of nondairy alternatives, particularly fruit juices, as carriers for probiotics. Lactic acid bacteria (LAB) have been identified as beneficial probiotics that can be incorporated into these beverages. The inclusion of prebiotics, such as inulin and galacto-oligosaccharides (GOS), in fruit juices has shown promise in enhancing the growth and activity of LAB, thereby creating functional beverages that support digestive health. Despite numerous studies on fruit juice fermentation, there is limited data on the optimal pairing of probiotics and prebiotics to develop stable, nondairy functional drinks. This review underscores the potential of lactic acid fermentation and the integration of prebiotics and probiotics in fruit juices, highlighting the necessity for further research to optimize these combinations for enhanced health benefits and improved beverage stability.

Antimicrobial Activity of Probiotic Bacteria Isolated from Plants: A Review

Lactic acid bacteria (LAB) constitute a heterogeneous group of bacteria isolated from fermented foods, animals, plants, and mammalian guts, with many health-promoting properties. Probiotics with antagonistic properties against human pathogens and foodborne bacteria have garnered significant attention from the scientific fraternity. A dedicated review focusing on plant-derived probiotic bacteria and their antagonistic properties has not been comprehensively reviewed. Thus, this review aimed at providing an overview of LAB isolates derived from several unconventional sources such as fruits, seeds, fruit pulp, leaves, roots, vegetables, grasses, and flowers and with their antibacterial, antifungal, and antiviral properties. This paper reviewed the antimicrobial properties of different genera, Lactobacillus, Leuconostoc, Weissella, Enterococcus, Pediococcus, Bacillus, and Fructobacillus, their postbiotics, and paraprobiotics. Several important mechanisms, including the secretion of bacteriocins, bacteriocin-like substances, reuterin, organic acids (lactic and acetic), peptides, exopolysaccharides, and hydrogen peroxide, have been attributed to their antimicrobial actions against pathogens. However, their precise mode of action is poorly understood; hence, further research should be conducted to reveal detailed mechanisms. Finally, the review discusses the summary and future implications. Given the significance, LAB and derived antimicrobial compounds can potentially be exploited in food preservation and safety or for medicinal applications after evaluating their safety.

Postbiotics in the Bakery Products: Applications and Nutritional Values

In recent years, the consumption of postbiotics has gained significant attention due to their potential health benefits. However, their application in the bakery industry remains underutilized. This review focuses on recent advances in the use of postbiotics, specifically the metabolites of lactic acid bacteria, in bakery products. We provide a concise overview of the multifaceted benefits of postbiotics, including their role as natural antioxidants, antimicrobials, and preservatives, and their potential to enhance product quality, extend shelf-life, and contribute to consumer welfare. This review combines information from various sources to provide a comprehensive update on recent advances in the role of postbiotics in bakery products, subsequently discussing the concept of sourdough as a leavening agent and its role in improving the nutritional profile of bakery products. We highlighted the positive effects of postbiotics on bakery items, such as improved texture, flavor, and shelf life, as well as their potential to contribute to overall health through their antioxidant properties and their impact on gut health. Overall, this review emphasizes the promising potential of postbiotics to revolutionize the bakery industry and promote healthier and more sustainable food options. The integration of postbiotics into bakery products represents a promising frontier and offers innovative possibilities to increase product quality, reduce food waste, and improve consumer health. Further research into refining techniques to incorporate postbiotics into bakery products is essential for advancing the health benefits and eco-friendly nature of these vital food items.

Investigation on L-rhamnose metabolism of Loigolactobacillus coryniformis subsp. coryniformis DSM 20001 and its propionate-containing fermentates

Propionate is an important short-chain carboxylic acid (SCCA) that serves as an effective antimicrobial agent for food preservation. Previous research has highlighted that few Lactobacillaceae can synthesize propionate by metabolizing deoxyhexoses via the fermentation intermediate 1,2-propanediol (1,2-PD). In this study, we investigated propionate production by Loigolactobacillus coryniformis subsp. coryniformis DSM 20001 while utilizing L-rhamnose as the primary carbon source. We cultivated L. coryniformis in small-scale anaerobic bioreactors at 30°C and pH 6.5 for 72 h and monitored the expression of key genes associated with deoxyhexose metabolism using quantitative PCR. In addition, we assessed the contribution of individual SCCA to the antimicrobial activity of the fermentate against common foodborne pathogens, including Escherichia coli, Salmonella enterica, Klebsiella oxytoca, Staphylococcus aureus, Candida albicans, Aspergillus niger, Penicillium roqueforti, and Penicillium purpurogenum using broth dilution assays. During cultivation, we observed the production of up to 16 mM propionate, alongside other metabolites such as lactate (26 mM), formate (2 mM), and acetate (4 mM), derived from 32 mM L-rhamnose. Genes related to L-rhamnose utilization were upregulated within the initial 48 h, while genes involved in 1,2-PD utilization remained highly transcribed throughout fermentation. Comparing the antimicrobial efficacy of the fermentates to synthetic SCCA mixtures, bacterial indicator strains were more sensitive than molds and yeast. Propionate was the primary SCCA responsible for inhibitory activity; inhibition was reduced if indicator strains were able to use lactate.IMPORTANCEWorldwide, approximately 30% of food produced is lost. Despite the application of complementary treatment methods, microbial food spoilage can occur along the entire value chain. The rising concern about food waste has led to increasing interest in natural preservation approaches. Lactobacillaceae fermentative systems produce a variety of short-chain carboxylic acid (SCCA) with antimicrobial potential, and we present here fundamental insight into the only recently discovered deoxyhexose metabolism of Loigolactobacillus coryniformis producing the antimicrobial SCCA propionate. We developed a bioprocess to produce propionate from L-rhamnose under controlled conditions as a first step toward the exploitation of L-rhamnose metabolism in the production of antimicrobial fermentates for use in the food industry, potentially replacing chemical alternatives. Our investigations highlight the major contribution of propionate in antimicrobial activity but also indicate the issue of co-occurring fermentable metabolites, which can affect the efficiency of fermentates.

Fermentation dynamics of millet beverages: Microbial interactions, nutritional enhancements, and health implications

Fermented millet beverages are gaining attention as a sustainable and nutritious alternative to traditional functional foods, combining the nutritional benefits of millets with the transformative effects of fermentation. This review explores the microbial dynamics, biochemical changes, and health benefits of these beverages. Fermentation boosts nutrient bioavailability, reduces anti-nutritional factors, and produces bioactive compounds like antioxidants and probiotics that support gut health, metabolism, and immunity. It also enhances the synthesis of vitamins, minerals, and peptides, offering potential benefits for managing chronic conditions. Key factors such as temperature, pH, oxygen levels, and substrate composition influence fermentation, with specific microorganisms enhancing both nutritional and sensory qualities. These beverages align with sustainability goals, as millets thrive in resource-limited environments, and their gluten-free nature caters to dietary needs, including those with celiac disease. The review highlights the cultural significance of millet beverages while advocating for their integration into modern health markets and commercial viability.

Effects of Kimchi-Derived Lactic Acid Bacteria on Reducing Biological Hazards in Kimchi

This study was performed to investigate the use of plant-based lactic acid bacteria (LAB) to reduce microbiological hazards in kimchi. Cell-free supernatants (CFS) from four LAB strains isolated from kimchi were tested for antimicrobial activity against five foodborne pathogens and two soft-rot pathogens. Each CFS showed antimicrobial activity against both foodborne and soft-rot pathogens. Washing salted kimchi cabbages inoculated with B. cereus with 5% CFS inhibited B. cereus to a greater extent than NaClO. The CFS from WiKim 83 and WiKim 87 exhibits inhibition rates of 25.09% and 24.21%, respectively, compared to the 19.19% rate of NaClO. Additionally, the CFS from WiKim 116 and WiKim 117 showed inhibition rates of 18.74% and 20.03%, respectively. Direct treatment of kimchi cabbage with soft-rot pathogens and CFS for five days inhibited the pathogens with similar efficacy to that of NaClO. To elucidate the antimicrobial activity mechanisms, pH neutralization, heat treatment, and organic acid analyses were performed. pH neutralization reduced the antimicrobial activity, whereas heat treatment did not, indicating that lactic, acetic, citric, and phenyllactic acids contribute to the thermal stability and antimicrobial properties of CFS. This study suggests that the four kimchi-derived LAB, which maintain a low pH through organic acid production, could be viable food preservatives capable of reducing biological hazards in kimchi.

Managing tomato bacterial wilt through pathogen suppression and host resistance augmentation using microbial peptide

The increasing health and environmental risks associated with synthetic chemical pesticides necessitate the exploration of safer, sustainable alternatives for plant protection. This study investigates a novel biosynthesized antimicrobial peptide (AMP) from Lactiplantibacillus argentoratensis strain IT, identified as the amino acid chain PRKGSVAKDVLPDPVYNSKLVTRLINHLMIDGKRG, for its efficacy in controlling bacterial wilt (BW) disease in tomato (Solanum lycopersicum) caused by Ralstonia solanacearum. Our research demonstrates that foliar application of this AMP at a concentration of 200 ppm significantly reduces disease incidence by 49.3% and disease severity by 45.8%. Scanning electron microscopy revealed severe morphological disruptions in the bacterial cells upon exposure to the AMP. Additionally, the AMP enhanced host resistance by elevating defense enzyme activities, leading to notable improvements in plant morphology, including a 95.5% increase in plant length, a 20.1% increase in biomass, and a 96.69% increase in root length. This bifunctional AMP provides dual protection by exerting direct antimicrobial activity against the pathogen and eliciting plant defense mechanisms. These findings underscore the potential of this biologically sourced AMP as a natural agent for combating plant diseases and promoting growth in tomato crops. To the best of our knowledge, this is the first study to demonstrate the use of a foliar spray application of a biosynthesized microbial peptide as biocontrol agent against R. solanacearum. This interaction not only highlights its biocontrol efficacy but also its role in promoting the growth of Solanum lycopersicum thereby increasing overall agricultural yield.

Untargeted metabolomics profiling for revealing water-soluble bioactive components and biological activities in edible bird's nest

Edible bird's nest (EBN) is a functional food renowned for its numerous health benefits. While its nutritional and therapeutic value is well-documented, the metabolites contributing to the bioactivities of EBN remain poorly understood. This study aimed to identify the metabolites present in EBN subjected to different treatments, including double-boiled EBN (EBNdb), EBN hydrolysate (EBNhydro), EBN fermented with Lactobacillus helveticus (EBNLH), Latilactobacillus curvatus (EBNLC), and Latilactobacillus sakei (EBNLS) using liquid chromatography-mass spectrometry (LC-MS) and correlate the identified bioactive metabolites with the bioactivities of EBN. It was found that the fermented EBNs exhibited the highest number of metabolites, with 76 tentatively identified, followed by EBNhydro (45) and EBNdb (37). Citric acid (1.97-4.48 g/kg) was present in all treated EBN samples, while L(+)-lactic acid (3.03-8.07 g/kg) and adipic acid (2.33-3.18 g/kg) were only found in fermented EBNs. Among the treated EBN samples, EBNLC demonstrated the significantly highest (p ≤ 0.05) antioxidative (22.34 ± 0.41 % 1,1-diphenyl-2-picrylhydrazil radical scavenging activity), antihypertensive (5.46 ± 0.26 % angiotensin-converting enzyme inhibitory activity), and antihyperglycemic activities (6.48 ± 0.34 % α-amylase inhibitory activity). A total of 18 metabolites, including citric acid, 4-sphingenin, N-acetylcitrulline, 4-aminophenol, L(+)-lactic acid, 2-oxoadipate, sildenafil, formylglycinamidin-RP, 11β,17α,21-α-5β-pregnane-3,20-dione, 2-ketobutyric acid, homoserine, benzaldehyde, 1-pyrroline4-hydroxy-2-carboxylate, nortriptyline, 1-methylguanine, 3-hydroxy-trimethyllysine, 3-phenylpropionate, and reserphine were predicted as bioactive metabolites using the partial least squares discriminant analysis (PLS-DA). This study provides valuable insights into the metabolites present in EBN and serves as fundamental data for future investigations into the bioactive compounds responsible for its specific health benefits, potentially leading to the development of enhanced EBN-based functional foods.

High-Throughput Sequencing Analysis of Microbiota and Enzyme Activities in Xiaoqu from Seven Provinces in Southern China

Xiaoqu, a pivotal starter in baijiu fermentation, provides the most microflora and enzymes to initiate and maintain baijiu brewing. This study aims to explore the differences in microbiota and enzyme activities among Xiaoqu samples from seven provinces in southern China using high-throughput sequencing, plate isolation, and activity detection. The analyses revealed significant differences in bacterial and fungal communities across the samples. A total of 22 bacterial species and 17 target fungal species were isolated and identified. Predominant bacteria included Bacillus (Bacillus subtilis) and lactic acid bacteria (LABs), while the fungal communities were primarily composed of yeasts (Saccharomyces cerevisiae) and various molds. The activities of α-amylase and glucoamylase varied significantly among the samples, and samples from HN1 and GZ2 exhibited the highest activities. Correlation analyses highlighted the pivotal role of LABs in maintaining acidity and the importance of molds and yeasts in the saccharification and fermentation processes. These findings shed light on the microbial composition and diversity of Xiaoqu and the critical role of microbes in baijiu production. Moreover, they suggested potential microbial resources for developing artificial Xiaoqu via synthetic microbial community in the future, enhancing baijiu fermentation efficiency and overall product quality.

Viability and functional impact of probiotic and starter cultures in salami-type fermented meat products

Salami, a well-known fermented meat product, is made from selected ground meat mixed with curing agents and spices. This work aimed to determine the viability of Lactiplantibacillus plantarum (as a starter), Lactobacillus acidophilus (probiotic microorganism), and their mixture during the fermentation and ripening of a salami-type product, evaluate the microbiological and physicochemical changes and assess the sensory acceptability of the final product. L. acidophilus has not been sufficiently explored as a probiotic in fermented meats, especially in terms of its effects on fermentation and sensory qualities. Salami-type products were formulated and fermented for 48 h at 32°C, and then ripening took place at 8°C for 13 days. pH, titratable acidity, Lactobacillus counts, and contaminating microbiota were analyzed during the process. Sensory evaluation was analyzed in the final products. The salami-type formulation served as an effective medium for growing microorganisms, with the populations of starter and probiotic cultures exceeding 108 CFU/g after fermentation and ripening for 15 days. The pH of the end products was ∼5.1, titratable acidity ∼2.5%, and aw ∼0.83. During fermentation and ripening, a significant reduction in total mesophilic aerobic bacteria (>7 logs), coliforms, and Staphylococcus aureus (>8-fold reductions) were observed. The sensory evaluation results indicate that the product's attributes are not influenced by the type of bacteria used, as no significant difference was found (p > 0.05). The results show that L. acidophilus, Lactiplantibacillus plantarum, or their mixture can be used as a starter culture in fermented meat products. Using L. acidophilus, whether alone or in combination, is a viable option that preserves the characteristics of the fermented product and may enhance the benefits of probiotic consumption.

Silk Fibroin Seed Coatings: Towards Sustainable Seed Protection and Enhanced Growth

Seed coating technology is vital in agriculture, enhancing seed protection and growth. However, conventional coatings often include chemical fungicides that pose environmental risks, highlighting the need for sustainable alternatives. This study explores silk fibroin (SF), a natural biopolymer with excellent film-forming properties, as a potential seed coating agent, addressing its antimicrobial limitations by combining it with the commercial agent CRUISER® and the antimicrobial peptide Nisin. Experimental methods included solution stability analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and growth assessments of wheat seeds. Findings reveal that silk fibroin-CRUISER® (SC) composites form stable β-sheet structures, enhancing the coating's mechanical strength. SF-based coatings improved seedling emergence rates (up to 1.65-fold), plant height (up to 1.05-fold), and root growth (up to 1.2-fold), especially under cold stress. The addition of Nisin further significantly boosted the antibacterial properties, providing sustained pathogen inhibition (p < 0.01). Identifying the optimal concentration of SF was essential for achieving a balance between protection and breathability, a key factor for industrial application. This research provides valuable insights into the development of eco-friendly seed coatings, presenting a viable and sustainable alternative to traditional chemical-based options in agricultural practices.

Valorization of Fruit By-Products Through Lactic Acid Fermentation for Innovative Beverage Formulation: Microbiological and Physiochemical Effects

The increase in food production is accompanied by an increase in waste, particularly agricultural by-products from cultivation and processing. These residues are referred to as agricultural by-products. To address this issue, biotechnological processes can be used to create new applications for these by-products. This study explored the use of LAB strains (Lactiplantibacillus plantarum, Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, and Limosilactobacillus fermentum) on by-products such as white grape pomace, cocoa bean shells, apple pomace, and defatted roasted hazelnut to develop yoghurt-style fruit beverages. Microbial load and pH changes were monitored during a 24 h fermentation and 14-day shelf life at 5 °C. Concentrations of sugars, organic acids, and volatile organic compounds were also analyzed using HPLC and GC-qMS. The results showed that optimizing the matrix led to significant bacterial growth, with viable microbes remaining under refrigeration. In particular, the strain of L. plantarum tested on the cocoa bean shell yielded the most promising results. After 24 h of fermentation, the strain reached a charge of 9.3 Log CFU/mL, acidifying the substrate to 3.9 and producing 19.00 g/100 g of lactic acid. Aromatic compounds were produced in all trials, without off-flavours, and characteristic fermented food flavours developed. Additionally, secondary metabolites produced by lactic acid bacteria may enhance the health benefits of these beverages.

Edible Coatings for Fish Preservation: Literature Data on Storage Temperature, Product Requirements, Antioxidant Activity, and Coating Performance-A Review

Fresh fish is among the most nutritive foodstuffs, but it is also the most perishable one. Therefore, huge efforts have been made to find the most suitable tools to deliver fish of the highest quality to exigent consumers. Scientific studies help the industry to exploit the newest findings to scale up emerging industrial technologies. In this review article, the focus is on the latest scientific findings on edible films used for fish coatings and storage. Since today's packaging processing and economy are governed by sustainability, naturality underpins packaging science. The synthesis of edible coatings, their components, processing advantages, and disadvantages are outlined with respect to the preservation requirements for sensitive fish. The requirements of coating properties are underlined for specific scenarios distinguishing cold and freezing conditions. This review raises the importance of antioxidants and their role in fish storage and preservation. A summary of their impact on physical, chemical, microbiological, and sensory alterations upon application in real fish is given. Studies on their influence on product stability, including pro-oxidant activity and the prevention of the autolysis of fish muscle, are given. Examples of lipid oxidation and its inhibition by the antioxidants embedded in edible coatings are given together with the relationship to the development of off-odors and other unwanted impacts. This review selects the most significant and valuable work performed in the past decade in the field of edible coatings whose development is on the global rise and adheres to food waste and sustainable development goals 2 (zero hunger), 3 (good health and well-being), and 12 (responsible consumption and production).

Biopreservation strategies using bacteriocins to control meat spoilage and foodborne outbreaks

Fresh meat is highly perishable, presenting challenges in spoilage mitigation and waste reduction globally. Despite the efforts, foodborne outbreaks from meat consumption persist. Biopreservation offers a natural solution to extend shelf life by managing microbial communities. However, challenges include the effective diffusion of bacteriocins through the meat matrix and the potential inhibition of starter cultures by bacteriocins targeting closely related lactic acid bacteria (LAB). LAB, predominant in meat, produce bacteriocins - small, stable peptides with broad antimicrobial properties effective across varying pH and temperature conditions. This review highlights the recent advances in the optimization of bacteriocin use, considering its structure and mode of action. Moreover, the strengths and weaknesses of different techniques for bacteriocin screening, including novel bioengineering methods, are described. Finally, we discuss the advantages and limitations of the modes of application of bacteriocins toward the preservation of fresh, cured, and novel meat products.

Research progress in the use of lactic acid bacteria as natural biopreservatives against Pseudomonas spp. in meat and meat products: A review

Meat and meat products represent excellent sources of key nutrients for human health, such as protein, essential amino acids, B vitamins, and minerals. However, they are recognized as highly perishable foods since they represent an ideal substrate for the growth of spoilage and pathogenic microorganisms. Meat spoilage is a complex process that involves multiple microorganisms and a combination of intrinsic and extrinsic ecological factors. One of the most common causative agents of meat spoilage is represented by species of the genus Pseudomonas. To prevent the development of such undesired microorganisms, chemical preservatives are usually exploited by the meat industry. However, the growing consumers' concerns about potential health issues linked to the consumption of chemical preservatives has prompted the food industry to develop alternative strategies to prevent microbial spoilage in meat and meat products. Besides to the application of physical strategies, the interest towards the use of natural preservatives, such as bioprotective microorganisms (e.g., lactic acid bacteria) and their metabolites, has rapidly grown. When used in meat and meat-based products, lactic acid bacteria exhibited a bioprotective activity against spoilage and even foodborne pathogens, thanks to the production of different inhibitory compounds including organic acids, bacteriocins, carbon dioxide, hydrogen peroxide, ethanol, N-diacetyl, and lactones. This bioprotective activity might justify the use of lactic acid bacteria or their metabolites as natural preservatives to extend the shelf-life of the products. However, the effectiveness of antimicrobial activity against Pseudomonas in meat and meat products still needs to be investigated to understand the influence of the type of end product, the type of packaging, and the storage conditions (time and temperature). Moreover, the antimicrobial activity of lactic acid bacteria must also be evaluated taking into consideration their ability to maintain the sensory features of fresh meat (whether whole or minced), without negatively affecting its sourness and acidity. Of note, the results herein discussed emphasize the challenges occurred in translating in vitro findings into practical applications due to the complex interactions between bacteria, antimicrobial compounds, and food matrices.

Linear-regression-based algorithms can succeed at identifying microbial functional groups despite the nonlinearity of ecological function

Microbial communities play key roles across diverse environments. Predicting their function and dynamics is a key goal of microbial ecology, but detailed microscopic descriptions of these systems can be prohibitively complex. One approach to deal with this complexity is to resort to coarser representations. Several approaches have sought to identify useful groupings of microbial species in a data-driven way. Of these, recent work has claimed some empirical success at de novo discovery of coarse representations predictive of a given function using methods as simple as a linear regression, against multiple groups of species or even a single such group (the ensemble quotient optimization (EQO) approach). Modeling community function as a linear combination of individual species' contributions appears simplistic. However, the task of identifying a predictive coarsening of an ecosystem is distinct from the task of predicting the function well, and it is conceivable that the former could be accomplished by a simpler methodology than the latter. Here, we use the resource competition framework to design a model where the "correct" grouping to be discovered is well-defined, and use synthetic data to evaluate and compare three regression-based methods, namely, two proposed previously and one we introduce. We find that regression-based methods can recover the groupings even when the function is manifestly nonlinear; that multi-group methods offer an advantage over a single-group EQO; and crucially, that simpler (linear) methods can outperform more complex ones.

Developmental Formulation Principles of Food Preservatives by Nanoencapsulation-Fundamentals, Application, and Challenges

The role of food additives is to preserve food by extending shelf life and limiting harmful microorganism proliferation. They prevent spoilage by enhancing the taste and safety of food by utilizing beneficial microorganisms and their antimicrobial metabolites. Current advances in food preservation and processing utilize green technology principles for green preservative formulation, enhancing nutrition and supplying essential micronutrients safely, while also improving quality, packaging, and food safety. Encapsulation is gaining attention for its potential to protect delicate materials from oxidative degradation and extend their shelf life, thereby ensuring optimal nutrient uptake. Nanoencapsulation of bioactive compounds has significantly improved the food, pharmaceutical, agriculture, and nutraceutical industries by protecting antioxidants, vitamins, minerals, and essential fatty acids by controlling release and ensuring delivery to specific sites in the human body. This emerging area is crucial for future industrial production, improving the sensory properties of foods like color, taste, and texture. Research on encapsulated bioactive compounds like bacteriocins, LAB, natamycin, polylysine, and bacteriophage is crucial for their potential antioxidant and antimicrobial activities in food applications and the food industry. This paper reviews nanomaterials used as food antimicrobial carriers, including nanoemulsions, nanoliposomes, nanoparticles, and nanofibers, to protect natural food antimicrobials from degradation and improve antimicrobial activity. This review discusses nanoencapsulation techniques for biopreservative agents like nisin, poly lysine, and natamycin, focusing on biologically-derived polymeric nanofibers, nanocarriers, nanoliposomes, and polymer-stabilized metallic nanoparticles. Nanomaterials, in general, improve the dispersibility, stability, and availability of bioactive substances, and this study discusses the controlled release of nanoencapsulated biopreservative agents.

Lactococcus lactis MA5 is a potential autochthonous probiotic for nutrient digestibility enhancement and bacterial pathogen inhibition in hybrid catfish (Ictalurus punctatus × I. furcatus)

With the emergence of diseases, the U.S. catfish industry is under challenge. Current trends prefer autochthonous bacteria as potential probiotic candidates owing to their adaptability and capacity to effectively colonize the host's intestine, which can enhance production performance and bolster disease resistance. The objective of this study was to isolate an autochthonous bacterium as probiotic for hybrid catfish. Initially, an analysis of the intestinal microbiota of hybrid catfish reared in earthen ponds was conducted for subsequent probiotic development. Twenty lactic acid bacteria were isolated from the digesta of overperforming catfish, and most of the candidates demonstrated probiotic traits, including proteolytic and lipolytic abilities; antagonistic inhibition of catfish enteric bacterial pathogens, negative haemolytic activity and antibiotic susceptibility. Subsequent to this screening process, an isolate of Lactococcus lactis (MA5) was deemed the most promising probiotic candidate. In silico analyses were conducted, and several potential probiotic functions were predicted, including essential amino acids and vitamin synthesis. Moreover, genes for three bacteriocins, lactococcin A, enterolysin A and sactipeptide BmbF, were identified. Lastly, various protectant media for lyophilization of MA5 were assessed. These findings suggest that Lactococcus lactis MA5 can be an autochthonous probiotic from hybrid catfish, holding promise to be further tested in feeding trials.

Staphylococcus aureus in Dairy Industry: Enterotoxin Production, Biofilm Formation, and Use of Lactic Acid Bacteria for Its Biocontrol

Staphylococcus aureus is a well-known pathogen capable of producing enterotoxins during bacterial growth in contaminated food, and the ingestion of such preformed toxins is one of the major causes of food poisoning around the world. Nowadays 33 staphylococcal enterotoxins (SEs) and SE-like toxins have been described, but nearly 95% of confirmed foodborne outbreaks are attributed to classical enterotoxins SEA, SEB, SEC, SED, and SEE. The natural habitat of S. aureus includes the skin and mucous membranes of both humans and animals, allowing the contamination of milk, its derivatives, and the processing facilities. S. aureus is well known for the ability to form biofilms in food processing environments, which contributes to its persistence and cross-contamination in food. The biocontrol of S. aureus in foods by lactic acid bacteria (LAB) and their bacteriocins has been studied for many years. Recently, LAB and their metabolites have also been explored for controlling S. aureus biofilms. LAB are used in fermented foods since in ancient times and nowadays characterized strains (or their purified bacteriocin) can be intentionally added to prolong food shelf-life and to control the growth of potentially pathogenic bacteria. Regarding the use of these microorganism and their metabolites (such as organic acids and bacteriocins) to prevent biofilm development or for biofilm removal, it is possible to conclude that a complex network behind the antagonistic activity remains poorly understood at the molecular level. The use of approaches that allow the characterization of these interactions is necessary to enhance our understanding of the mechanisms that govern the inhibitory activity of LAB against S. aureus biofilms in food processing environments.

Insights on the microbiology of Ethiopian fermented milk products: A review

Fermented milk products play a vital role in the diets of Ethiopians. They are produced from either spontaneous fermentation or back-slopping methods at the household level, in which lactic acid bacteria (LAB) and yeasts predominate. As a result, the processing steps are not standardized and overall safety is still of public health relevance. Therefore, quality and safety improvement, standardization of traditional manufacturing practices, and commercialization of products to a wider market are important. Hence, this systematic review aimed to provide a comprehensive overview of the microbiology of traditional Ethiopian fermented milk products, including ergo (spontaneously fermented whole milk), dhanaan (fermented camel milk), ititu (concentrated sour milk or spontaneously fermented milk curd), ayib (traditional cottage cheese), qibe (traditional butter), arrera (defatted buttermilk), and hazo (spiced fermented buttermilk). We followed the Preferred Reporting Items for Systematic Reviews and searched relevant databases and search engines, including the Web of Science, Google Scholar, Scopus, PubMed, ScienceDirect, and ResearchGate. Furthermore, the pertinent literature was checked individually and identified. Dairy fermentation provides shelf-life extension and improves the organoleptic quality of products. Nonetheless, the aforementioned Ethiopian fermented foods may be contaminated with Escherichia coli 0157: H7, Listeria monocytogenes, Salmonella spp., or Staphylococcus aureus due to inadequate processing and handling practices. This systematic review also revealed that these traditional milk products lack consistent quality and safety due to poor hygienic preparation techniques, non-controlled fermentation, and limited knowledge or awareness of small-holder dairy farmers. Therefore, the use of suitable procedures including good hygienic practices and controlled fermentation is recommended.

Bioprocessing strategies for enhanced probiotic extracellular vesicle production: culture condition modulation

Probiotic extracellular vesicles are biochemically active structures responsible for biological effects elicited by probiotic bacteria. Lactobacillus spp., which are abundant in the human body (e.g., gut), are known to have anti-inflammatory and antimicrobial properties, and are commonly used in food products, supplements, and in discovery research. There is increasing evidence that Lactobacillus-derived extracellular vesicles (LREVs) have potent immunomodulatory capacity that is superior to probiotics themselves. However, key mechanistic insights into the process that controls production and thus, the function of LREVs, are lacking. Currently, it is unknown how the probiotic culture microenvironment orchestrates the type, yield and function of LREVs. Here, we investigated how multifactor modulation of the biomanufacturing process controls the yield and biological functionality of the LREVs. To achieve this, we selected Lacticaseibacillus rhamnosus as the candidate probiotic, initially cultivated under traditional culture conditions, i.e., 100% broth concentration and pH 5.5. Subsequently, we systematically modified the culture conditions of the probiotic by adjusting three critical process parameters: (1) culture medium pH (pH 3.5, 5.5 and 7.5), (2) growth time (48 and 72 h), and (3) broth concentration (50% and 10% of original broth concentration). EVs were then isolated separately from each condition. The critical quality attributes (CQA) of LREVs, including physical characteristics (size, distribution, concentration) and biological composition (protein, carbohydrate, lipid), were analysed. Functional impacts of LREVs on human epidermal keratinocytes and Staphylococcus aureus were also assessed as CQA. Our findings show that the production of LREVs is influenced by environmental stresses induced by the culture conditions. Factors like broth concentration, pH levels, and growth time significantly impact stress levels in L. rhamnosus, affecting both the production and composition of LREVs. Additionally, we have observed that LREVs are non-toxicity for keratinocytes, the major cell type of the epidermis, and possess antimicrobial properties against S. aureus, a common human skin pathogen. These properties are prerequisites for the potential application of EVs to treat skin conditions, including infected wounds. However, the functionality of LREVs depends on the culture conditions and stress levels experienced by L. rhamnosus during production. Understanding this relationship between the culture microenvironment, probiotic stress response, and LREV characteristics, can lead to the biomanufacturing of customised probiotic-derived EVs for various medical and industrial applications.

Application of Natural Functional Additives for Improving Bioactivity and Structure of Biopolymer-Based Films for Food Packaging: A Review

The global trend towards conscious consumption plays an important role in consumer preferences regarding both the composition and quality of food and packaging materials, including sustainable ones. The development of biodegradable active packaging materials could reduce both the negative impact on the environment due to a decrease in the use of oil-based plastics and the amount of synthetic preservatives. This review discusses relevant functional additives for improving the bioactivity of biopolymer-based films. Addition of plant, microbial, animal and organic nanoparticles into bio-based films is discussed. Changes in mechanical, transparency, water and oxygen barrier properties are reviewed. Since microbial and oxidative deterioration are the main causes of food spoilage, antimicrobial and antioxidant properties of natural additives are discussed, including perspective ones for the development of biodegradable active packaging.

Synthetic microbial communities: Novel strategies to enhance the quality of traditional fermented foods

Consumers are attracted to traditional fermented foods due to their unique flavor and nutritional value. However, the traditional fermentation technique can no longer accommodate the requirements of the food industry. Traditional fermented foods produce hazardous compounds, off-odor, and anti-nutritional factors, reducing product stability. The microbial system complexity of traditional fermented foods resulting from the open fermentation process has made it challenging to regulate these problems by modifying microbial behaviors. Synthetic microbial communities (SynComs) have been shown to simplify complex microbial communities and allow for the targeted design of microbial communities, which has been applied in processing traditional fermented foods. Herein, we describe the theoretical information of SynComs, particularly microbial physiological processes and their interactions. This paper discusses current approaches to creating SynComs, including designing, building, testing, and learning, with typical applications and fundamental techniques. Based on various traditional fermented food innovation demands, the potential and application of SynComs in enhancing the quality of traditional fermented foods are highlighted. SynComs showed superior performance in regulating the quality of traditional fermented foods using the interaction of core microorganisms to reduce the hazardous compounds of traditional fermented foods and improve flavor. Additionally, we presented the current status and future perspectives of SynComs for improving the quality of traditional fermented foods.

Investigating lactic acid bacteria genus Lactococcus lactis properties: Antioxidant activity, antibiotic resistance, and antibacterial activity against multidrug-resistant bacteria Staphylococcus aureus

Background

Lactic acid bacteria (LAB) are utilized as a starter culture in the manufacturing of fermented dairy items, as a preservative for various food products, and as a probiotic. In our country, some research has been carried out, even if LAB plays a principal role in food preservation and improves the texture and taste of fermented foods, that is why we tried to evaluate their probiotic effect. The objective of this research was to determine the antibacterial activity of Lactococcus lactis (L. lactis) against Staphylococcus aureus (S. aureus) ATCC 29213, investigate their antioxidant activity, and characterize their sensitivity against 18 antibiotics.

Methods

A total of 23 LAB (L. lactis subsp. cremoris, L. lactis subsp. Lactis diacetylactis, L. lactis subsp. lactis) were isolated from cow's raw milk. The antibacterial activity was performed using two techniques, competition for nutrients and a technique utilizing components nature, using the disk diffusion method. The sensitivity of the studied LAB to different antibiotics was tested on Man rogosa sharp (MRS) agar using commercial antibiotic disks. All strains of LAB were examined for their antioxidant activity. The antioxidant activity of L. lactis was tested by 2,2-diphenyl-1 picrylhydrazyl (DPPH).

Results

The results showed that the MRS medium was more adapted than Muller Hinton Agar (MHA) to investigate the antibacterial activity of L. lactis against S. aureus ATCC 29213. Also, L. lactis exhibited a notable degree of antibacterial activity against S. aureus ATCC 29213. L. Lactis subsp. Lactis displayed higher antibacterial activities, followed by L. lactis ssp. lactis biovar. diacetylactis, and lastly, L. lactis ssp. cremoris against S. aureus ATCC 29213. Lc 26 among all strains of L. lactis showed a high potential antibacterial activity reaching 40 ± 3 mm against S. aureus ATCC 29213. All strains of L. lactis showed a slightly moderate antioxidant activity (10.56 ± 1.28%-26.29 ± 0.05 %). The results of the antibiotic resistance test indicate that all strains of L. lactis were resistant to cefotaxime, sulfamethoxazole-trimethoprim, and streptomycin and were sensitive to Ampicillin, Amoxicillin, Penicillin G, Teicoplanin, Vancomycin, Gentamicin 500, Tetracycline, and Chloramphenicol. These test results indicate that this strain falls within the criteria of not posing any harmful effects on human health. The important antibacterial properties recorded for all L. Lactis strains were derived from the production of antibacterial active metabolites, such as protein, diacetyl, hydrogen peroxide, and lactic acid, together with the fight for nutrients.

Conclusion

This study suggests that the strains of L. lactis could be added as an antibacterial agent against S. aureus ATCC 29213 and can provide an important nutritional property for their antioxidant potential.

Contribution of Microbiota to Bioactivity Exerted by Bee Bread

Bee-collected pollen (BCP) and bee bread (BB) are honey bee products known for their beneficial biological properties. The main goal of this study was to investigate BB microbiota and its contribution to bioactivity exerted by BB. The microbiota of BB samples collected at different maturation stages was investigated via culture-independent (Next Generation Sequencing, NGS) and culture-dependent methods. Microbial communities dynamically fluctuate during BB maturation, ending in a stable microbial community structure in mature BB. Bee bread bacterial isolates were tested for phenotypes and genes implicated in the production and secretion of enzymes as well as antibacterial activity. Out of 309 bacterial isolates, 41 secreted hemicellulases, 13 cellulases, 39 amylases, 132 proteinases, 85 Coomassie brilliant blue G or R dye-degrading enzymes and 72 Malachite Green dye-degrading enzymes. Furthermore, out of 309 bacterial isolates, 42 exhibited antibacterial activity against Staphylococcus aureus, 34 against Pseudomonas aeruginosa, 47 against Salmonella enterica ser. Typhimurium and 43 against Klebsiella pneumoniae. Artificially fermented samples exerted higher antibacterial activity compared to fresh BCP, strongly indicating that BB microbiota contribute to BB antibacterial activity. Our findings suggest that BB microbiota is an underexplored source of novel antimicrobial agents and enzymes that could lead to new applications in medicine and the food industry.

Leuconostoc gelidum Is the Major Species Responsible for the Spoilage of Cooked Sausage Packaged in a Modified Atmosphere, and Hop Extract Is the Best Inhibitor Tested

Cooked sausages packaged in a modified atmosphere (MAP: 20% CO2, 70% N2, <0.2% O2) with evident yellow stains were analyzed. The aims of this work were to study the microbial cause of the spoilage and to evaluate different antimicrobial compounds to prevent it. Leuconostoc gelidum was identified as the primary cause of the yellow coating in spoiled cooked sausage, as confirmed by its intentional inoculation on slices of unspoiled sausage. Leuconostoc gelidum was the main bacteria responsible for the yellow coating in spoiled cooked sausage, as confirmed by its intentional inoculation on slices of unspoiled sausage. The yellow color was also evident during growth in the model system containing cooked sausage extract, but the colonies on MRS agar appeared white, demonstrating that the food substrate stimulated the production of the yellow pigment. The spoilage was also characterized by different volatile compounds, including ketones, ethanol, acetic acid, and ethyl acetate, found in the spoiled cooked sausage packages. These compounds explained the activity of Leuc. gelidum because they are typical of heterofermentative LAB, cultivated either on food substrates or in artificial broths. Leuc. gelidum also produced slight swelling in the spoiled packages. The efficacy of different antimicrobials was assessed in model systems composed of cooked sausage extract with the antimicrobials added at food product concentrations. The data showed that sodium lactate, sodium acetate, and a combination of sodium lactate and sodium diacetate could only slow the growth of the spoiler-they could not stop it from occurring. Conversely, hop extract inhibited Leuc. gelidum, showing a minimal inhibitory concentration (MIC) of approximately 0.008 mg CAE/mL in synthetic broth and 4 mg CAE/kg in cooked sausage slices. Adding hop extract at the MIC did not allow Leuc. gelidum growth and did not change the sensorial characteristics of the cooked sausages. To our knowledge, this is the first report of the antimicrobial activities of hop extracts against Leuc. gelidum either in vitro or in vivo.

Probiotic Potential and Application of Indigenous Non-Starter Lactic Acid Bacteria in Ripened Short-Aged Cheese

There are massive sources of lactic acid bacteria (LAB) in traditional dairy products. Some of these indigenous strains could be novel probiotics with applications in human health and supply the growing needs of the probiotic industry. In this work, were analyzed the probiotic and technological properties of three Lactobacilli strains isolated from traditional Brazilian cheeses. In vitro tests showed that the three strains are safe and have probiotic features. They presented antimicrobial activity against pathogenic bacteria, auto-aggregation values around 60%, high biofilm formation properties, and a survivor of more than 65% to simulated acid conditions and more than 100% to bile salts. The three strains were used as adjunct cultures separately in a pilot-scale production of Prato cheese. After 45 days of ripening, the lactobacilli counts in the cheeses were close to 8 Log CFU/g, and was observed a reduction in the lactococci counts (around -3 Log CFU/g) in a strain-dependent manner. Cheese primary and secondary proteolysis were unaffected by the probiotic candidates during the ripening, and the strains showed no lipolytic effect, as no changes in the fatty acid profile of cheeses were observed. Thus, our findings suggest that the three strains evaluated have probiotic properties and have potential as adjunct non-starter lactic acid bacteria (NSLAB) to improve the quality and functionality of short-aged cheeses.

Microbiological and physicochemical profile of Italian steak tartare and predicting growth potential of Listeria monocytogenes

In the present study, growth potential of Listeria monocytogenes in steak tartare samples taken at retail and belonging to 13 brands marketed in Northern Italy was investigated. The samples were submitted to microbiological and chemical-physical characterization. The data obtained were used as inputs for the application of the predictive microbiology software FSSP that allows the estimation of the growth of L. monocytogenes during the shelf-life. Lactic acid bacteria, the main component of the microflora, gave variable counts among the brands (from 3.38 to 6.24 log CFU/g). pH and aw values were always higher than 5.3 and 0.96, respectively, thus they could not be considered as single efficient hurdles to prevent the growth of L. monocytogenes according to the EC Reg. 2073/2005; the same was observed for salt content (constantly <2 %) and nitrites (not quantifiable in all the samples, even if declared in some labels). Nevertheless, the combination of all the hurdles, evaluated by predictive microbiology using critical development factors, resulted in an estimated growth <0.5 log CFU/g throughout the shelf life; this output allowed us to consider all the steak tartare analysed as unfavourable substrate for L. monocytogenes growth. The information obtained could be useful for tartare producers as well as for competent authority to evaluate the effective risk concerning these typology of products.

Harnessing the Health and Techno-Functional Potential of Lactic Acid Bacteria: A Comprehensive Review

This review examines the techno-functional properties of lactic acid bacteria (LABs) in the food industry, focusing on their potential health benefits. We discuss current findings related to the techno-functionality of LAB, which includes acidification, proteolytic and lipolytic features, and a variety of other biochemical activities. These activities include the production of antimicrobial compounds and the synthesis of exopolysaccharides that improve food safety and consumer sensory experience. LABs are also known for their antioxidant abilities, which help reduce oxidative reactions in foods and improve their functional properties. In addition, LABs' role as probiotics is known for their promising effects on gut health, immune system modulation, cholesterol control, and general wellbeing. Despite these advantages, several challenges hinder the effective production and use of probiotic LABs, such as maintaining strain viability during storage and transport as well as ensuring their efficacy in the gastrointestinal tract. Our review identifies these critical barriers and suggests avenues for future research.

Valorization of Dairy and Fruit/Berry Industry By-Products to Sustainable Marinades for Broilers' Wooden Breast Meat Quality Improvement

The study aims to improve the quality of wooden breast meat (WBM) via the use of newly developed marinades based on selected strains of lactic acid bacteria (LAB) in combination with the by-products of the dairy and fruit/berry industries. Six distinct marinades were produced based on milk permeate (MP) fermented with Lacticaseibacillus casei (Lc) and Liquorilactobacillus uvarum (Lu) with the addition of apple (ApBp) and blackcurrant (BcBp) processing by-products. The microbiological and acidity parameters of the fermented marinades were evaluated. The effects of marinades on the microbiological, technical, and physicochemical properties of meat were assessed following 24 and 48 h of WBM treatment. It was established that LAB viable counts in marinades were higher than 7.00 log10 colony-forming units (CFU)/mL and, after 48 h of marination, enterobacteria and molds/yeasts in WBM were absent. Marinated (24 and 48 h) WBM showed lower dry-matter and protein content, as well as water holding capacity, and exhibited higher drip loss (by 8.76%) and cooking loss (by 12.3%) in comparison with controls. After WBM treatment, biogenic amines decreased; besides, the absence of spermidine and phenylethylamine was observed in meat marinated for 48 h with a marinade prepared with Lu. Overall, this study highlights the potential advantages of the developed sustainable marinades in enhancing the safety and quality attributes of WBM.

Comparative Genomics Reveals Genetic Diversity and Variation in Metabolic Traits in Fructilactobacillus sanfranciscensis Strains

Fructilactobacillus sanfranciscensis is a significant and dominant bacterial species of sourdough microbiota from ecological and functional perspectives. Despite the remarkable prevalence of different strains of this species in sourdoughs worldwide, the drivers behind the genetic diversity of this species needed to be clarified. In this research, 14 F. sanfranciscensis strains were isolated from sourdough samples to evaluate the genetic diversity and variation in metabolic traits. These 14 and 31 other strains (obtained from the NCBI database) genomes were compared. The values for genome size and GC content, on average, turned out to 1.31 Mbp and 34.25%, respectively. In 45 F. sanfranciscensis strains, there were 162 core genes and 0 to 51 unique genes present in each strain. The primary functions of core genes were related to nucleotide, lipid transport, and amino acid, as well as carbohydrate metabolism. The size of core genes accounted for 41.18% of the pan-genome size in 14 F. sanfranciscensis strains, i.e., 0.70 Mbp of 1.70 Mbp. There were genetic variations among the 14 strains involved in carbohydrate utilization and antibiotic resistance. Moreover, exopolysaccharides biosynthesis-related genes were annotated, including epsABD, wxz, wzy. The Type IIA & IE CRISPR-Cas systems, pediocin PA-1 and Lacticin_3147_A1 bacteriocins operons were also discovered in F. sanfranciscensis. These findings can help to select desirable F. sanfranciscensis strains to develop standardized starter culture for sourdough fermentation, and expect to provide traditional fermented pasta with a higher quality and nutritional value for the consumers.

A selection process based on the robustness of anti-Listeria monocytogenes activity reveals two strains of Carnobacterium maltaromaticum with biopreservation properties in cheese

Biopreservation is an approach consisting of using microorganisms as protective cultures and/or their metabolites to optimize the microbiological quality and shelf life of food by ensuring safety or reducing food waste. Biopreservation strain selection pipelines mainly focus on inhibition strength to identify strains of interest. However, in addition to inhibition strength, inhibition activity must be able to be expressed despite significant variations in food matrix properties. In this study, the anti-Listeria monocytogenes EGDelux properties of a collection of 77 Carnobacterium maltaromaticum strains were investigated by high throughput competition assays under varying conditions of co-culture inoculation level, time interval between inoculation with C. maltaromaticum and L. monocytogenes, pH, and NaCl, resulting in 1309 different combinations of C. maltaromaticum strains and culture conditions. This screening led to the selection of two candidate strains with potent and robust anti-L. monocytogenes activities. Deferred growth inhibition assays followed by halo measurements, and liquid co-culture followed by colony counting, revealed that these two strains exhibit a wide anti-Listeria spectrum. Challenge tests in Camembert and Saint-Nectaire cheese revealed both strains were able to inhibit a cocktail of five strains of L. monocytogenes with high potency and high reproducibility. These results highlight the importance of including the robustness criterion in addition to potency when designing a strain selection process for biopreservation applications.

Metabolite profiling and bioactivity guided fractionation of Lactobacillaceae and rice bran postbiotics for antimicrobial-resistant Salmonella Typhimurium growth suppression

Probiotic-fermented supplements (postbiotics) are becoming increasingly explored for their activity against antibiotic-resistant enteropathogens. Prebiotics are often incorporated into postbiotics to enhance their efficacy, but due to strain differences in probiotic activity, postbiotic antimicrobial effects are poorly understood. To improve postbiotic antimicrobial efficacy, we investigated and compared metabolite profiles of postbiotics prepared with three lactic acid bacteria strains (L. fermentum, L. paracasei, and L. rhamnosus) cultured with and without rice bran, a globally abundant, rich source of prebiotics. At their minimum inhibitory dose, L. fermentum and L. paracasei postbiotics + rice bran suppressed S. Typhimurium growth 42-55% more versus their respective probiotic-alone postbiotics. The global, non-targeted metabolome of these postbiotics identified 109 metabolites increased in L. fermentum and L. paracasei rice bran postbiotics, including 49 amino acids, 20 lipids, and 12 phytochemicals metabolites. To identify key metabolite contributors to postbiotic antimicrobial activity, bioactivity-guided fractionation was applied to L. fermentum and L. paracasei rice bran-fermented postbiotics. Fractionation resulted in four L. fermentum and seven L. paracasei fractions capable of suppressing S. Typhimurium growth more effectively versus the negative control. These fractions were enriched in 15 metabolites that were significantly increased in the global metabolome of postbiotics prepared with rice bran versus postbiotic alone. These metabolites included imidazole propionate (enriched in L. fermentum + rice bran, 1.61-fold increase; L. paracasei + rice bran 1.28-fold increase), dihydroferulate (L. fermentum + rice bran, 5.18-fold increase), and linoleate (L. fermentum + rice bran, 1.82-fold increase; L. paracasei + rice bran, 3.19-fold increase), suggesting that they may be key metabolite drivers of S. Typhimurium growth suppression. Here, we show distinct mechanisms by which postbiotics prepared with lactic acid bacteria and rice bran produce metabolites with antimicrobial activity capable of suppressing S. Typhimurium growth. Probiotic strain differences contributing to postbiotic antimicrobial activity attract attention as adjunctive treatments against pathogens.

Harnessing the dual nature of Bacillus (Weizmannia) coagulans for sustainable production of biomaterials and development of functional food

Bacillus coagulans, recently renamed Weizmannia coagulans, is a spore-forming bacterium that has garnered significant interest across various research fields, ranging from health to industrial applications. The probiotic properties of W. coagulans enhance intestinal digestion, by releasing prebiotic molecules including enzymes that facilitate the breakdown of not-digestible carbohydrates. Notably, some enzymes from W. coagulans extend beyond digestive functions, serving as valuable biotechnological tools and contributing to more sustainable and efficient manufacturing processes. Furthermore, the homofermentative thermophilic nature of W. coagulans renders it an exceptional candidate for fermenting foods and lignocellulosic residues into L-(+)-lactic acid. In this review, we provide an overview of the dual nature of W. coagulans, in functional foods and for the development of bio-based materials.

In-vitro selection of lactic acid bacteria to combat Salmonella enterica and Campylobacter jejuni in broiler chickens

Campylobacter and Salmonella are the two most prominent foodborne zoonotic pathogens reported in the European Union. As poultry is one of the major sources of these pathogens, it is imperative to mitigate the colonization of these pathogens in poultry. Many strains of lactic acid bacteria (LAB) have demonstrated anti-Salmonella and anti-Campylobacter characteristics to varying degrees and spectrums which are attributed to the production of various metabolites. However, the production of these compounds and consequent antimicrobial properties are highly strain dependent. Therefore, the current study was performed to select a potent LAB and determine its causal attribute in inhibiting Salmonella enterica and Campylobacter jejuni, in-vitro. Six LAB (Lactiplantibacillus plantarum (LP), Lacticaseibacillus casei (LC), Limosilactobacillus reuteri (LR), Lacticaseibacillus rhamnosus (LRh), Leuconostoc mesenteroides (LM) and Pediococcus pentosaceus (PP)) and three serovars of Salmonella enterica (Typhimurium, Enterica and Braenderup) and Campylobacter jejuni were used in the current study. Spot overlays, well diffusion, co-culture and co-aggregation assays against Salmonella and well diffusion assays against Campylobacter jejuni were performed. Organic acid profiling of culture supernatants was performed using HPLC. The results indicated that LRh, LM and PP had the most significant anti-Salmonella effects while LP, LC, LM and PP displayed the most significant anti-Campylobacter effects. Lactic acid and formic acid detected in the culture supernatants seem the most likely source of the anti-Salmonella and anti-Campylobacter effects exhibited by these LAB. In conclusion, Leuconostoc mesenteroides displayed the most significant overall anti-pathogenic effects when compared to the other LAB strains studied, indicating its potential application in-vivo.

Anaerobic flora, Selenomonas ruminis sp. nov., and the bacteriocinogenic Ligilactobacillus salivarius strain MP3 from crossbred-lactating goats

This study aimed to examine the distribution of anaerobic bacteria in the rumen fluid of Thai crossbred goats and to screen potential probiotic strains capable of producing antimicrobial compounds and inhibiting bacteria that cause milk fat depression. Thirty-four strains of bacteria from the rumen fluid were divided into 13 groups within 12 genera based on 16S rRNA gene sequences. The RF1-5 and RF5-12 were identified as Streptococcus luteliensis and Bacillus licheniformis, respectively, and demonstrated non-ropy exopolysaccharide. Furthermore, mPRGC5T was closely related to Selenomonas caprae JCM 33725 T (97.8% similarity) based on 16S rRNA gene sequences. It exhibited low average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values with related type strains ranging from 84.9 to 86.0%, 21.3 to 21.8%, and 73.8 to 76.1%, respectively. The genotypic and phenotypic characteristics of mPRGC5T strongly support this strain as a new species of the genus Selenomonas for which the name Selenomonas ruminis mPRGC5T was proposed. The type strain is mPRGC5T (= JCM 33724 T = KCTC 25177 T). Ligilactobacillus salivarius MP3 showed antibacterial activity against Cutibacterium acnes subsp. acnes DSM 1897 T and Kocuria rhizophila MIII. The enterolysin A cluster gene was identified in its genome. The auto-aggregation of L. salivarius MP3 was 93.6 ± 0.2%. Additionally, co-aggregation of L. salivarius MP3 with C. acnes DSM 1897 T and K. rhizophila MIII had 92.2 ± 3.4% and 87.3 ± 4.5%, respectively. The adhesion capacity of strain MP3 was 76.11 ± 2.2%. Probiogenomic analysis revealed that L. salivarius MP3 was nonhazardous to animal supplementation and included acid- and bile-tolerant ability. However, strain MP3 contained three antibiotic resistance genes. Thus, the supplementation of L. salivarius MP3 could increase the milk fat content by suppressing C. acnes DSM 1897 T with antibiotic resistance gene horizontal transfer awareness.