Role of Lactic Acid Bacteria in Food Preservation and Safety

Lactic acid bacterial fermentation as a biotransformation strategy to enhance the bioavailability of phenolic antioxidants in fruits and vegetables: A comprehensive review

Fruits and vegetables (FVs) are rich sources of macro and micro-nutrients crucial for a healthy diet. In addition to these nutrients, FVs also contain fibre and phytochemicals known for their antioxidant properties. Despite the growing evidence of the disease-preventive role of antioxidants in FVs, their bioavailability and bioaccessibility vary significantly and have not been adequately explored. Lactic acid bacterial (LAB) fermentation is considered the most appropriate and accessible biotechnological approach to maintain and enhance the safety, nutritional, sensory and shelf-life properties of perishable foods such as FVs. This review critically assesses how LAB fermentation could be utilised as a promising biotransformation strategy to enhance the bioavailability of antioxidants in FVs. Furthermore, it discusses the potential use of uniquely nutritious Australian native fruits as suitable candidates for LAB fermentation. Further research is essential to identify the beneficial properties of bioactive compounds and effective LAB-based biotransformation strategies to improve the bioavailability and bioaccessibility of antioxidants in FVs.

Lactic acid fermentation of non-conventional plant-based protein extract

The increasing demand for plant-based foods necessitates the development of effective preservation methods to ensure safety and quality. This study evaluated the effectiveness of biopreservation using eight plant-based protein extracts (PBPEs) (pea, faba, soy, potato, pumpkin, hazelnuts, rice, and hemp) fermented with 12 different lactic acid bacteria (LAB) strains from four species. The effectiveness of LAB biopreservation was assessed both at the endpoint and in real-time using impedometric analysis and was found to depend on both the matrix and the strain. Among the 12 LAB strains, Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus showed the highest adaptability, particularly in soy, faba, and hemp protein extracts, highlighting their potential as effective biopreservative agents for diverse PBPEs. Given the distinctive advantage of biopreservation in enhancing organoleptic properties, this aspect was also evaluated for the two most effective LAB strains. Fermentation with L. delbrueckii subsp. bulgaricus 1932 and L. plantarum 4193 significantly improved the aroma profile of fermented PBPEs (pea, faba, soy, pumpkin, rice, and hemp) where they exhibited the best adaptability. Notably, levels of hexanal and hexanoic acid, compounds often associated with off-flavors, were markedly reduced, enhancing the organoleptic properties of the final products. These findings emphasize the dual benefits of LAB fermentation as a natural preservative and flavor enhancer, with promising implications for its application in the food industry.

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.

Bioactive Compounds and Antioxidant Properties of Sheep's Milk Yogurt Enriched with a Postbiotic Extract from Lactiplantibacillus plantarum UCLM56: Effects of In Vitro Digestion and Fermentation

Lactic acid bacteria present in yogurts produce bioactive compounds, such as gamma-aminobutyric acid (GABA) and short-chain fatty acids (SCFAs). Sheep's milk yogurt is an excellent medium to enhance their bioactive properties. In this study, the impact of adding an extract derived from the GABA-producing strain Lactiplantibacillus plantarum UCLM56 to sheep's milk yogurt was evaluated in terms of its bioactive and antioxidant properties. Samples were subjected to in vitro digestion and fermentation to simulate the effects of the gastrointestinal tract. GABA, SCFAs, amino acids, biogenic amines, antioxidant capacity, and organic acid levels were analyzed. Yogurt enriched with UCLM56 postbiotic extract showed higher levels of GABA and propionic acid, with increases of more than 360 and 260%, respectively, along with an improved antioxidant capacity (FRAP and DPPH methods) compared to conventional yogurt. After in vitro fermentation, the levels of lactic and propionic acids were significantly higher in the enriched yogurt (50 and 41% increases, respectively), as well as the antioxidant capacity (more than 200% improvement). In conclusion, the use of Lactiplantibacillus plantarum UCLM56 extract enhances the bioactive properties of sheep's milk yogurt, making it a promising option for developing functional dairy products with added value.

Isolation and preliminary screening of lactic acid bacteria for antimicrobial potential from raw milk

Lactic acid bacteria (LAB) are widely recognized for their role in food preservation and their potential to produce bacteriocins, natural antimicrobial peptides effective against a broad spectrum of foodborne pathogens. This study focuses on the isolation and characterization of bacteriocin-producing LAB strains from raw milk samples collected in southern and Northern Morocco. Phenotypic and genotypic methods were used to identify the isolated strains, and their antimicrobial activity was evaluated against common foodborne pathogens, including Escherichia coli and Salmonella spp. The results revealed several LAB strains with significant bacteriocin production and strong inhibitory effects against the target pathogens. These findings highlight the potential applications of these strains in the food industry, particularly for enhancing the safety and shelf life of fermented food products. This study provides a foundation for future research on the biotechnological exploitation of LAB as natural food preservatives.

A Review on Recent Trends in Bacteriophages for Post-Harvest Food Decontamination

Infectious diseases resulting from unsafe food consumption are a global concern. Despite recent advances and control measures in the food industry aimed at fulfilling the growing consumer demand for high-quality and safe food products, infection outbreaks continue to occur. This review stands out by providing an overview of post-harvest food decontamination methods against some of the most important bacterial foodborne pathogens, with particular focus on the advantages and challenges of using phages, including their most recent post-harvest applications directly to food and integration into active food packaging systems, highlighting their potential in providing safer and healthier food products. The already approved commercial phage products and the numerous available studies demonstrate their antibacterial efficacy against some of the most problematic foodborne pathogens in different food products, reinforcing their possible use in the future as a current practice in the food industry for food decontamination. Moreover, the incorporation of phages into packaging materials holds particular promise, providing protection against harsh conditions and enabling their controlled and continuous release into the food matrix. The effectiveness of phage-added packaging materials in reducing the growth of pathogens in food systems has been well-demonstrated. However, there are still some challenges associated with the development of phage-based packaging systems that need to be addressed with future research.

Isolation and Characterization of Enterocin-Producing Enterococcus faecium Strains from Algerian Traditional Food "Dried Figs Marinated in Olive Oil": Functional and Safety Evaluations

The increasing consumer demand for natural and sustainable food preservation methods has highlighted the potential of lactic acid bacteria (LAB) and their bioactive metabolites, particularly bacteriocins, as effective antimicrobial agents. This study aimed to isolate and characterize Enterococcus faecium strains from Algerian traditional dried figs marinated in olive oil, a nutrient-dense and underexplored food matrix. Twelve isolates were identified as E. faecium using MALDI-TOF MS and 16S rRNA gene sequencing, ensuring precise taxonomic classification. Genotypic analyses (BOX-PCR, GTG-PCR, and ERIC-PCR) revealed substantial genetic diversity, with BOX-PCR demonstrating superior discriminatory power. Functional screening confirmed the presence of enterocin genes, including entA (100% of strains), entB (60%), and entL50A/B (20%), which correlated with inhibition zones against Enterococcus faecium VCY, Micrococcus luteus GPE 3001, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, and Acinetobacter lwoffii GPE 3002. Genotype-phenotype correlation analysis identified strain HFM7 as the most potent antimicrobial strain, exhibiting the largest inhibition zone (20.0 ± 1.0 mm) and harboring three enterocin genes (entA, entL50A, and entL50B). Protease sensitivity confirmed the proteinaceous nature of the antimicrobial compounds. Importantly, no virulence factors (esp, gelE, and hyl) or antibiotic resistance genes (vanA, vanB, ermA, ermB, and aac(6')-Ie-alph(2″)) were detected, underscoring the safety of these isolates for food applications. These findings suggest that E. faecium strains from traditional foods are promising candidates as natural biopreservatives and starter cultures in clean-label food systems. By bridging traditional food ecosystems and modern biotechnological advancements, this study provides a foundation for sustainable, minimally processed food preservation strategies with potential applications in enhancing food safety and shelf life.

Overview of Glycometabolism of Lactic Acid Bacteria During Freeze-Drying: Changes, Influencing Factors, and Application Strategies

Lactic acid bacteria (LAB) play a vital role in food fermentation and probiotics microeconomics. Freeze-drying (FD) is a commonly used method for preserving LAB powder to extend its shelf life. However, FD induces thermal, osmotic, and mechanical stresses that can impact the glycometabolism of LAB, which is the process of converting carbohydrates into energy. This review explores the effect of FD on glycometabolism, factors influencing glycometabolism, and feasible strategies in the FD process of LAB. During the three stages of FD, freezing, primary drying or sublimation, and second drying, the glycolytic activity of LAB is disrupted in the freezing stage; further, the function of glycolytic enzymes such as hexokinase, phosphofructokinase, and pyruvate kinase is hindered, and adenosine triphosphate (ATP) production drops significantly in the sublimation stage; these enzyme activities and ATP production nearly cease and exopolysaccharide (EPS) synthesis alters during the secondary drying stage. Factors such as strain variations, pretreatment techniques, growth medium components, FD parameters, and water activity influence these changes. To counteract the effects of FD on LAB glycometabolism, strategies like cryoprotectants, encapsulation, and genetic engineering can help preserve their glycometabolic activity. These methods protect LAB from harsh FD conditions, safeguarding glycolytic flux and enzymatic processes involved in carbohydrate metabolism. A deeper understanding of these glycometabolic changes is essential for optimizing FD processes and enhancing the use of LAB in food, medicine, and biotechnology, ultimately improving their performance upon rehydration.

Leuconostoc lactis strain APC 3969 produces a new variant of cyclic bacteriocin leucocyclicin Q and displays potent anti-Clostridium perfringens activity

Clostridium perfringens is an important foodborne pathogen that produces diverse toxins and is often associated with foodborne gastroenteritis. In this sense, novel biopreservatives with anti-C. perfringens activity are of interest. Among them, bacteriocins produced by lactic acid bacteria stand out as potential candidates. This study describes leucocyclicin C, a novel variant of the bacteriocin leucocyclicin Q, capable of inhibiting C. perfringens. The bacteriocin comprises 61 amino acids, has a molecular mass of 6,081.44 Da, and is produced by the strain Leuconostoc lactis APC 3969. Like many circular bacteriocins, leucocyclicin C has a broad spectrum of activity, is protease resistant, and has high stability against thermic and pH stresses. The leucocyclicin C genetic cluster comprises ten genes instead of the five genes previously described for leucocyclicin Q. Also, this genetic cluster seems to be part of a putative composite transposon. Leucocyclicin C has a minimum inhibitory concentration (MIC) of 3.288 µM against C. perfringens, comparable with other antimicrobial peptides. These results suggest that leucocyclicin C has the potential as a biopreservative for controlling C. perfringens in food.

Antibacterial Activity, Probiotic Potential, and Biocontrol Efficacy of Two Lactic Acid Bacteria Against Penicillium expansum on Fresh Grapes

Lactic acid bacteria are commonly present in various sources and possess significant probiotic properties. They can inhibit pathogenic bacteria and fungi simultaneously, making them promising candidates as bio-preservatives. This study investigated two potential probiotic strains: Lactiplantibacillus plantarum LR5-2 (isolated from fermented meat products) and Lacticaseibacillus rhamnosus SQ63 (isolated from infant feces). The study evaluated their aggregation ability, anti-pathogenic activity, safety, and tolerance to gastrointestinal conditions, phenol, and bile salts. Additionally, their biological control potential against Penicillium expansum on fresh grapes was assessed. The results demonstrated that both strains exhibited high survival rates under extreme gastrointestinal conditions, enhanced Auto-aggregation, co-aggregation, and hydrophobicity. They displayed strong antioxidant activity and significant antibacterial effects against 11 pathogenic fungi and foodborne pathogens. Biosafety testing revealed that both strains are sensitive to most antibiotics, do not produce biogenic amines, and exhibit no hemolytic or DNase activity. In grapes, L. plantarum LR5-2 and L. rhamnosus SQ63 significantly reduced the incidence and disease index of P. expansum infection. In conclusion, the characterization analysis and bio-preservation experiments revealed that LR5-2 and SQ63 have strong potential as probiotics and bio-preservatives.

Analysis of Olive Oil Mill Wastewater from Conventionally Farmed Olives: Chemical and Microbiological Safety and Polyphenolic Profile for Possible Use in Food Product Functionalization

This study aimed to perform an in-depth investigation of olive oil mill wastewater (OOMW). Two OOMW samples (OOMW-A and OOMW-B) from conventionally farmed olives were collected from two different olive oil mills in Palermo province (Italy). Multiresidual analysis indicated that both OOMW samples were unsuitable for food production due to pesticide residues. Specifically, OOMW-A contained 4 active compounds totaling 5.7 μg/L, while OOMW-B had 16 analytes with a total content of 65.8 μg/L. However, polyphenol analysis in the OOMW revealed 23 compounds with high concentrations of hydroxytyrosol, secoiridoid derivatives, phenolic acids, flavones, and total polyphenol content ranging from 377.5 μg/mL (for OOMW-B) to 391.8 μg/mL (for OOMW-A). The microbiological analysis of OOMW samples revealed only detectable viable bacteria (102 CFU/mL) of the lactic acid bacteria (LAB) group. Two distinct LAB strains, Lactiplantibacillus plantarum OMW1 and Leuconostoc mesenteroides OMW23, were identified. These strains demonstrated notable acidification capabilities and produced antibacterial compounds. In conclusion, despite the high polyphenolic content and microbiological suitability of OOMW, the presence of micro-contaminants hinders their use in food production. Thus, further studies are underway to investigate OOMW from organically farmed olives for bakery product functionalization, employing the two selected LAB strains resistant to olive polyphenols as leavening agents.

LTX-315 is a novel broad-spectrum antimicrobial peptide against clinical multidrug-resistant bacteria

INTRODUCTION

Infections stemming from multidrug-resistant bacteria present a substantial threat to public health today. Discovering or synthesizing novel compounds is crucial to alleviate this pressing situation.

OBJECTIVE

The main purpose of this study is to verify the antibacterial activity of LTX-315 and explore its primary action mode.

METHODS

Through antibacterial phenotype assay screening, we obtained a potent compound named LTX-315 from diverse drug libraries, 10,926 compounds in total. Then, the bactericidal effect and its action mode were explored through biochemical and chemistry methods such as atime-killing curve, scanning electronic microscopy, isothermal titration calorimetry analysis, and nuclear magnetic resonance. Finally, the efficacy in vivo of LTX-315 against drug-resistant bacteria was proved through amice infection model.

RESULTS

In this study, LTX-315, an oncolytic peptide, was discovered to effectively eliminate gram-positive and gram-negative pathogens, even for those multidrug-resistant strains. Through strong electrostatic interactions, LTX-315 can bind to the membrane component phosphatidylglycerol (PG) with extremely high affinity (nanomolar level). Strikingly, in contrast to the typical electrostatic interactions of antibacterial peptides, the indole group of LTX-315, situated near the alkyl chain, exhibits significantly enhanced recognition and interaction with PG due to the hydrophobic effect of the alkyl chain. Furthermore, it exerts various impacts on cell membranes, including damaging integrity, increasing permeability, and decreasing membrane fluidity. Additionally, microscopy revealed significant cell disintegration. The influence, in turn, disrupts several physiological activities inside cells, such as increasing the reactive oxygen species level, ultimately leading to cell death. Finally, the efficacy of LTX-315 in vivo against multidrug-resistant and hypervirulent Klebsiella pneumoniae was demonstrated.

CONCLUSION

The unique mechanism of LTX-315 involves high-affinity binding to PG and subsequent membrane disruption, providing a novel approach against multidrug-resistant bacteria compared to conventional antibiotics. As a potential candidate, it shows promise in effectively treating bacterial infections, particularly those caused by drug-resistant bacteria, thereby addressing the escalating challenge of antibiotic resistance worldwide.

Microbial Fermentation in Food and Beverage Industries: Innovations, Challenges, and Opportunities

Microbial fermentation is a primary method by which a variety of foods and beverages are produced. The term refers to the use of microbes such as bacteria, yeasts, and molds to transform carbohydrates into different substances. Fermentation is important for preserving, enhancing flavor, and improving the nutritional quality of various perishable foods. Historical records clearly show that fermented foods and drinks, such as wine, beer, and bread, have been consumed for more than 7000 years. The main microorganisms employed were Saccharomyces cerevisiae, which are predominantly used in alcohol fermentation, and Lactobacillus in dairy and vegetable fermentation. Typical fermented foods and drinks made from yogurt, cheese, beer, wine, cider, and pickles from vegetables are examples. Although there are risks of contamination and spoilage by pathogenic and undesirable microorganisms, advanced technologies and proper control procedures can mitigate these risks. This review addresses microbial fermentation and clarifies its past importance and contribution to food preservation, flavoring, and nutrition. It systematically separates yeasts, molds, and bacteria and explains how they are used in food products such as bread, yogurt, beer, and pickles. Larger producers employ primary production methods such as the artisanal approach, which are explored along with future trends such as solid-state fermentation, the potential of biotechnology in developing new products, and sustainability in new product development. Future research and development strategies can lead to innovations in methods that improve efficiency, product range, and sustainability.

The Role of Probiotics in Skin Care: Advances, Challenges, and Future Needs

The skin, being the largest organ in the human body, plays a pivotal role in safeguarding the body against invasive pathogens. Therefore, it is essential to reinforce and protect this vital organ. Current research supports the impact of probiotics on skin health and their ability to alleviate various skin disorders. However, the effectiveness and probable side effects of probiotics in skin care remain a subject of debate, necessitating further investigation and analysis. Hence, this study aims to highlight existing gaps and future needs in the current research on probiotics in skin care and pave the way for future investigations. Therefore, we scrutinized the effects of oral (fermented foods and dietary supplements) and non-oral/topical probiotics on skin care, and the mechanism of probiotics that affect skin health. The results of most studies showed that fermented foods containing probiotics, particularly dairy products, positively impact skin health. The research results regarding the efficacy of probiotic supplements and live strains in treating skin disorders show promising potential. However, safety evaluations are crucial, to identify any potential adverse effects. While research has identified numerous potential mechanisms by which probiotics may influence skin health, a complete understanding of their precise mode of action remains elusive. However, it seems that probiotics can exert their positive effects through the gut-skin and gut-skin-brain axis on the human body. Therefore, following the identification of safe probiotics, additional studies should be carried out to establish optimal dosages, potential side effects, suitable regulatory guidelines, and validation methods.

The Combined Use of High Pressure Processing and Lactic Acid Containing Fermentate on Inactivation of Salmonella, Shiga Toxin-producing E. coli, and Listeria monocytogenes in Raw Pet Foods

Raw meat pet foods can pose health risks to pets and humans. High-pressure processing (HPP) was used in a previous study to demonstrate its effectiveness in achieving a 5-log reduction of Salmonella, E. coli STEC, and L. monocytogenes in commercially available raw pet foods and maintaining the 5-log reduction throughout shelf-life with frozen storage being more effective than refrigerated. L. monocytogenes, being more HPP resistant, could potentially regrow when stored at refrigeration temperatures and required further optimization. Chicken-based raw diet pet food was inoculated with 7-8 log CFU/g cocktails of Salmonella spp., E. coli STEC, or L. monocytogenes and stored at 4 °C for 24 h before the addition of either 0.7% or 1.0% w/v lactic acid fermentate (LAF) and HPP treated at 586 MPa for 2, 3, and 4 min after 24 or 72 h storage at 4 °C. HPP-treated products were stored frozen (-10 to -16 °C) up to 21 days with microbiological analyses on days 1, 3, 5, 7, 14, and 21. All HPP-and LAF-treated samples demonstrated a 5-log reduction of Salmonella spp., E. coli STEC, and L. monocytogenes. Samples without LAF and HPP treated after 24 h storage at 4 °C resulted in an average 4.02 log cfu/g reduction of L. monocytogenes with 2 min HPP hold time while longer HPP hold times at 4 min improved L. monocytogenes reduction by 0.35 log cfu/g. E. coli was found to be more HPP resistant in this study than L. monocytogenes and the addition of LAF had a significant impact on the overall pathogen survival during post-HPP storage. Based on qualitative enrichment data for each pathogen, the use of LAF resulted in more complete inactivation compared to samples without LAF. The use of 1% LAF in combination with 586 MPa for 4 min was found to be most effective for the inactivation of Salmonella spp., E. coli STEC, and L. monocytogenes. The findings are significant as it provides both formulation and processing controls to ensure the safety of raw diet pet foods.

Effects of Lactiplantibacillus plantarum LM1215 on Candida albicans and Gardnerella vaginalis

PURPOSE

The aim of this study was to identify novel vaginal probiotics with the potential to prevent vulvovaginal candidiasis (VVC) and bacterial vaginosis (BV).

MATERIALS AND METHODS

Eighteen strains of Lactiplantibacillus plantarum were isolated from healthy Korean women, and their antimicrobial effects against Candida albicans and Gardnerella vaginalis were assessed. Three strains (L. plantarum LM1203, LM1209, and LM1215) were selected for further investigation, focusing on their growth inhibition, biofilm regulation, and cellular mechanisms against these vaginal pathogens. Additionally, electron microscopy revealed damage to G. vaginalis induced by L. plantarum LM1215, and genomic analysis was conducted on this strain.

RESULTS

L. plantarum LM1203, LM1209, and LM1215 showed approximately 1 and 2 Log CFU/mL growth reduction in C. albicans and G. vaginalis, respectively. These L. plantarum strains effectively inhibited biofilm formation and eliminated the mature biofilms formed by C. albicans. Furthermore, L. plantarum LM1215 decreased tricarboxylic acid cycle activity by 51.75 (p<0.001) and respiratory metabolic activity by 52.88% (p<0.001) in G. vaginalis. L. plantarum induced cellular membrane damage, inhibition of protein synthesis, and cell wall collapse in G. vaginalis. Genomic analysis confirmed L. plantarum LM1215 as a safe strain for vaginal probiotics.

CONCLUSION

The L. plantarum LM1215 is considered a safe probiotic agent suitable for the prevention of VVC and BV.

Impact of Metabolites from Foodborne Pathogens on Cancer

Foodborne pathogens are microorganisms that cause illness through contamination, presenting significant risks to public health and food safety. This review explores the metabolites produced by these pathogens, including toxins and secondary metabolites, and their implications for human health, particularly concerning cancer risk. We examine various pathogens such as Salmonella sp., Campylobacter sp., Escherichia coli, and Listeria monocytogenes, detailing the specific metabolites of concern and their carcinogenic mechanisms. This study discusses analytical techniques for detecting these metabolites, such as chromatography, spectrometry, and immunoassays, along with the challenges associated with their detection. This study covers effective control strategies, including food processing techniques, sanitation practices, regulatory measures, and emerging technologies in pathogen control. This manuscript considers the broader public health implications of pathogen metabolites, highlighting the importance of robust health policies, public awareness, and education. This review identifies research gaps and innovative approaches, recommending advancements in detection methods, preventive strategies, and policy improvements to better manage the risks associated with foodborne pathogens and their metabolites.

Multifunctional Applications of Lactic Acid Bacteria: Enhancing Safety, Quality, and Nutritional Value in Foods and Fermented Beverages

Lactic Acid Bacteria (LAB) have garnered significant attention in the food and beverage industry for their significant roles in enhancing safety, quality, and nutritional value. As starter cultures, probiotics, and bacteriocin producers, LAB contributes to the production of high-quality foods and beverages that meet the growing consumer demand for minimally processed functional and health-promoting food products. Industrial food processing, especially in the fresh produce and beverage sector, is shifting to the use of more natural bioproducts in food production, prioritizing not only preservation but also the enhancement of functional characteristics in the final product. Starter cultures, essential to this approach, are carefully selected for their robust adaptation to the food environment. These cultures, often combined with probiotics, contribute beyond their basic fermentation roles by improving the safety, nutritional value, and health-promoting properties of foods. Thus, their selection is critical in preserving the integrity, quality, and nutrition of foods, especially in fresh produce and fruits and vegetable beverages, which have a dynamic microbiome. In addition to reducing the risk of foodborne illnesses and spoilage through the metabolites, including bacteriocins they produce, the use of LAB in these products can contribute essential amino acids, lactic acids, and other bioproducts that directly impact food quality. As a result, LAB can significantly alter the organoleptic and nutritional quality of foods while extending their shelf life. This review is aimed at highlighting the diverse applications of LAB in enhancing safety, quality, and nutritional value across a range of food products and fermented beverages, with a specific focus on essential metabolites in fruit and vegetable beverages and their critical contributions as starter cultures, probiotics, and bacteriocin producers.

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).

Fermentation for Revalorisation of Fruit and Vegetable By-Products: A Sustainable Approach Towards Minimising Food Loss and Waste

In a world increasingly focused on sustainability and integrated resource use, the revalorisation of horticultural by-products is emerging as a key strategy to minimise food loss and waste while maximising value within the food supply chain. Fermentation, one of the earliest and most versatile food processing techniques, utilises microorganisms or enzymes to induce desirable biochemical transformations that enhance the nutritional value, digestibility, safety, and sensory properties of food products. This process has been identified as a promising method for producing novel, high-value food products from discarded or non-aesthetic fruits and vegetables that fail to meet commercial standards due to aesthetic factors such as size or appearance. Besides waste reduction, fermentation enables the production of functional beverages and foods enriched with probiotics, antioxidants, and other bioactive compounds, depending on the specific horticultural matrix and the types of microorganisms employed. This review explores the current bioprocesses used or under investigation, such as alcoholic, lactic, and acetic acid fermentation, for the revalorisation of fruit and vegetable by-products, with particular emphasis on how fermentation can transform these by-products into valuable foods and ingredients for human consumption, contributing to a more sustainable and circular food system.

Recent Advancements in Harnessing Lactic Acid Bacterial Metabolites for Fruits and Vegetables Preservation

Postharvest losses in fruits and vegetables exert substantial economic and environmental repercussions. Chemical interventions are being widely utilized for the past six decades which may lead to significant health complications. Bioprotection of fruits and vegetables is the need of the hour in which use of lactic acid bacteria (LAB) with GRAS status predominantly stands out. Incorporation of LAB in postharvest fruits and vegetables suppresses the growth of spoilage organisms by synthesizing various antimicrobial compounds such as bacteriocins, organic acids, hydrogen peroxide (H2O2), exopolysaccharides (EPS), and BLIS. For example, Pediococcus acidilactici, Lactobacillus plantarum, and Limosilactobacillus fermentum convert natural sugars in fruits and vegetables to lactic acid and create an acidic environment that do not favour spoilage organisms. LAB can improve the bioavailability of vitamins and minerals and enrich the phenolic profile and bioactivity components. LAB has remarkable physiological characteristics like resistance towards bacteriophage, proteolytic activity, and polysaccharide production which adds to the safety of foods. They modify the sensory properties and preserve the nutritional quality of fruits and vegetables. They can also perform therapeutic role in the intestinal tract as they tolerate low pH, high salt concentration. Thus application of LAB, whether independently or in conjunction with stabilizing agents as edible coatings, is regarded as an exceptionally promising methodology for ensuring safer consumption of fruits and vegetables. This review addresses the most recent research findings that harness the antagonistic property of lactic acid bacterial metabolites, formulations and coatings containing their bioactive compounds for extended shelf life of fruits and vegetables.

Application of a Multi-Gas Detector for Monitoring Gas Composition in Minced Beef During Storage

This study aims to assess the capability of using a specially designed device to monitor changes in gas concentration (CO2, NH3, H2S, and O2) in the atmosphere above the minced beef meat, during storage at refrigerated temperature. With its array of sensing channels, the multi-gas detector device facilitates the detection of precise gas concentrations in sensitive environments, enabling the monitoring of various processes occurring within stored meat. To delve into the connection between microbial activity and gas emissions during storage, fluctuations in microbial populations in the meat were observed, focusing on prevalent meat microbiota such as lactic acid bacteria (LAB) and Enterobacteriaceae. A significant reduction of O2 content in the stored samples was observed after seven days (p < 0.05), while a significant release of CO2 was detected on the fourth day of storage. Significant changes (p < 0.05) in the gas content were tracked until the 11th day of storage followed by intensive microbial growth. NH3 and H2S levels remained undetectable throughout the experiment. The results showed a correlation between an increase in gas content in the headspace and an increase in the number of LAB and Enterobacteriaceae in meat. Modern multi-gas detector devices can indirectly determine microbial contamination in closed meat packaging.

Editorial for Special Issue "Role of Microorganisms and Their Metabolites in Agriculture, Food and the Environment"

Microorganisms and their metabolites play a crucial role in agriculture, food production, and environmental sustainability, offering solutions to challenges like soil degradation, pest management, and climate resilience [...].

Protective effect of Bifidobacterium animalis CGMCC25262 on HaCaT keratinocytes

Bifidobacteria are the most prevalent members of the intestinal microbiota in mammals and other animals, and they play a significant role in promoting gut health through their probiotic effects. Recently, the potential applications of Bifidobacteria have been extended to skin health. However, the beneficial mechanism of Bifidobacteria on the skin barrier remains unclear. In this study, keratinocyte HaCaT cells were used as models to evaluate the protective effects of the cell-free supernatant (CFS), heat-inactivated bacteria, and bacterial lysate of Bifidobacterium animalis CGMCC25262 on the skin barrier and inflammatory cytokines. The results showed that all the tested samples were able to upregulate the transcription levels of biomarker genes associated with the skin barrier, such as hyaluronic acid synthetase (HAS) and aquaporins (AQPs). Notably, the transcription of the hyaluronic acid synthetase gene-2 (HAS-2) is upregulated by 3~4 times, and AQP3 increased by 2.5 times when the keratinocyte HaCaT cells were co-incubated with 0.8 to 1% CFS. In particular, the expression level of Filaggrin (FLG) in HaCaT cells increased by 1.7 to 2.7 times when incubated with Bifidobacterial samples, reaching its peak at a concentration of 0.8% CFS. Moreover, B. animalis CGMCC25262 also decreased the expression of the proinflammatory cytokine RANTES to one-tenth compared to the levels observed in HaCaT cells induced with tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). These results demonstrate the potential of B. animalis CGMCC25262 in protecting the skin barrier and reducing inflammatory response.

Protective effects of fermented Rosa roxburghii Tratt juice against ethanol‑induced hepatocyte injury by regulating the NRF2‑AMPK signaling pathway in AML‑12 cells

Alcohol‑related liver disease (ALD) is a major health concern worldwide. In recent years, there has been growing interest in natural products and functional foods for preventing and treating ALD due to their potential antioxidant and hepatoprotective properties. Rosa roxburghii Tratt, known for its rich content of bioactive compounds, has demonstrated promising health benefits, including anti‑inflammatory and antioxidant effects. Fermentation has been utilized as a strategy to enhance the bioavailability and efficacy of natural products. In the present study, using a mixture of Rosa roxburghii Tratt juice, lotus leaf extract and grape seed proanthocyanidins fermented by Lactobacillus plantarum HH‑LP56, a novel fermented Rosa roxburghii Tratt (FRRT) juice was discovered that can prevent and regulate ethanol‑induced liver cell damage. Following fermentation, the pH was significantly decreased, and the content of VC and superoxide dismutase (SOD) were significantly increased, along with a noticeable enhancement in hydroxyl and 2,2‑diphenyl‑1‑picrylhydrazyl free radical scavenging abilities. Alpha Mouse liver 12 cells were exposed to ethanol for 24 h to establish an in vitro liver cell injury model. The present study evaluated the effects of FRRT on cell damage, lipid accumulation and oxidative stress markers. The results revealed that FRRT pretreatment (cells were pre‑treated with 2.5 and 5 mg/ml FRRT for 2 h) significantly reduced lipid accumulation and oxidative stress in liver cells. Mechanistically, FRRT regulated lipid metabolism by influencing key genes and proteins, such as AMP‑activated protein kinase, sterol regulatory element binding transcription factor 1 and Stearyl‑CoA desaturase‑1. Furthermore, FRRT enhanced antioxidant activity by increasing SOD activity, glutathione and catalase levels, while reducing reactive oxygen species and malondialdehyde levels. It also reversed the expression changes of ethanol‑induced oxidative stress‑related genes and proteins. In conclusion, a novel functional food ingredient may have been discovered with extensive potential applications. These findings indicated that FRRT has antioxidant properties and potential therapeutic benefits in addressing ethanol‑induced liver cell damage through its effects on liver lipid metabolism and oxidative stress.

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.

Dellaglioa Algida Cell-Free Supernatant Inhibits Pseudomonas Fluorescence and Pseudomonas Fragi by Destroying Cell Membranes

The aim of this study was to examine the components of the cell-free supernatant (CFS) derived from a novel strain of psychrophilic Lactobacillus, Dellaglioa algida, and to further elucidate the impact of this CFS on various cellular processes. Specifically, we sought to understand its effects on the cell membrane, protein and DNA release, protease activity, and metabolites of Pseudomonas fluorescens and Pseudomonas fragi, thereby clarifying the antibacterial mechanism involved. The CFS components were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS), the Coomassie Brilliant Blue method, and the phenol-sulfuric acid method. The inhibitory effect of the CFS on Pseudomonas fluorescens and Pseudomonas fragi was assessed using the ethidium bromide (EB) assay, Oxford cup assay, and ultramicroassay. Additionally, we analyzed the metabolites produced by Pseudomonas fluorescens and Pseudomonas fragi when treated with the CFS. The findings reveal that the CFS of Dellaglioa algida contains 94 volatile components, with protein and sugar concentrations of 32.857 ± 0.9705 mg/mL and 98.250 ± 4.210 mg/L, respectively. The CFS induces varying degrees of damage to the cell membranes of both Pseudomonas fluorescens and Pseudomonas fragi, leading to the release of intracellular proteins and DNA. Furthermore, the CFS reduced the protease activity and metabolic capacity of Pseudomonas fluorescens and Pseudomonas fragi. These results enhance our understanding of the mechanism by which psychrophilic Dellaglioa algida inhibits Pseudomonas fluorescens and Pseudomonas fragi, confirming that its inhibitory effect predominantly occurs through damage to the biological cell membranes of Pseudomonas. Dellaglioa algida is a newly identified cold-adapted inhibitor of Pseudomonas, indicating that its CFS is an effective microbial inhibitor in cold environments. This discovery suggests potential applications in inhibiting the growth and reproduction of Pseudomonas fluorescens and Pseudomonas fragi in food, pharmaceuticals, perfumes, and other chemicals, providing a valuable new reference for industrial preservation.

Determination of Opium Alkaloid Content in Poppy Seeds Using Liquid Chromatography Coupled with a Mass Spectrometer with a Time-of-Flight Analyzer (UPLC-TOF-HRMS)

Opium poppy is a plant used in both the pharmaceutical and food industries. Substances found on the surface of dry poppy seeds belong to the group of opium alkaloids. However, the presence of these substances in food products poses a risk to consumer health, which is why new permissible levels for both substances in poppy seeds and derivative products have been introduced in Regulation (EU) 2023/915. This research aimed to analyze the content of all six opium alkaloids in poppy seeds provided directly by producers as well as those available on the local market in Poland. The research confirmed the presence of morphine in all examined poppy seed samples. The alkaloid content ranged from 12.46 to 102.86 mg/kg for seeds purchased in local markets and from 1.1 to 110.1 mg/kg for seeds obtained directly from producers. Both groups showed similar levels of morphine content as well as other OAs, which significantly exceeded the permissible limit of 20 mg/kg set by the European Commission (EU) 2023/915. These results indicate that the presence of morphine and other opium alkaloids in poppy seeds exceeds permissible levels, posing a serious health issue and necessitating further research and improvement in processing methods.

Optimisation ofLevilactobacillus brevis-fermented finger millet (Eleusine coracana) and evaluation of its effects on cancer cells (HCT116 and MDA-MB-231)

The objective of this study was to optimise the millet formulation using Levilactobacillus brevis and to evaluate its anticarcinogenic potential in vitro. The formula was developed in the course of the fermentation of finger millet (Eleusine coracana) using L. brevis MTTC 4460 and optimised by response surface methodology and validation by artificial neural networking (ANN). The optimised millet formulation could be obtained using 2 % of bacterial inoculum, 2 % of glucose, and a fermentation duration of 3.3 days with a yield of 5.98 mg/mL lactic acid and 3.38 log10 (CFU/mL) viable L. brevis with overall desirability value of 1. The fermented millet formulation exhibited antiproliferative and antimigratory effects on MDA-MB-231 and HCT116 cancer cell lines. In addition, the outcomes observed in western blot analysis revealed that the formulation elicited apoptotic responses mediated by the Bcl-2 family of proteins in MDA-MB-231 and HCT116 cell lines while demonstrating no discernible impact on HEK293 normal cells.

Polar-Region Soils as Novel Reservoir of Lactic Acid Bacteria from the Genus Carnobacterium

Polar habitats offer excellent sites to isolate unique bacterial strains due to their diverse physical, geochemical, and biological factors. We hypothesize that the unique environmental conditions of polar regions select for distinct strains of lactic acid bacteria (LAB) with novel biochemical properties. In this study, we characterized ten strains of psychrotrophic LAB isolated from hitherto poorly described sources-High Arctic and maritime Antarctic soils and soil-like materials, including ornithogenic soils, cryoconites, elephant seal colonies, and postglacial moraines. We evaluated the physiological and biochemical properties of the isolates. Based on 16S rRNA and housekeeping genes, the four LAB strains were assigned to three Carnobacterium species: C. alterfunditum, C. maltaromaticum, and C. jeotgali. The remaining strains may represent three new species of the Carnobacterium genus. All isolates were neutrophilic and halophilic psychrotrophs capable of fermenting various carbohydrates, organic acids, and alcohols. The identified metabolic properties of the isolated Carnobacterium strains suggest possible syntrophic interactions with other microorganisms in polar habitats. Some showed antimicrobial activity against food pathogens such as Listeria monocytogenes and human pathogens like Staphylococcus spp. Several isolates exhibited unique metabolic traits with potential biotechnological applications that could be more effectively exploited under less stringent technological conditions compared to thermophilic LAB strains, such as lower temperatures and reduced nutrient concentrations. Analysis of extrachromosomal genetic elements revealed 13 plasmids ranging from 4.5 to 79.5 kb in five isolates, featuring unique genetic structures and high levels of previously uncharacterized genes. This work is the first comprehensive study of the biochemical properties of both known and new Carnobacterium species and enhances our understanding of bacterial communities in harsh and highly selective polar soil ecosystems.

Overview of cloning in lactic acid bacteria: Expression and its application of probiotic potential in inflammatory bowel diseases

Inflammatory bowel disease (IBD) imposes a significant impact on the quality of life for affected individuals. However, there was a current lack of a systematic summary regarding the latest epidemic trends and the underlying pathogenesis of IBD. This highlights the need for a thorough examination of both the epidemiological aspects of IBD and the specific mechanisms by which lactic acid bacteria (LAB) contribute to mitigating this condition. In developed countries, higher incidences and death rates of IBD have been observed, influenced by a combination of environmental and genetic factors. LAB offer significant advantages and substantial potential for enhancing IBD treatment. LAB's capabilities include the production of bioactive metabolites, regulation of gut immunity, protection of intestinal mechanical barriers, inhibition of oxidative damage, and restoration of imbalanced gut microbiota. The review suggests that screening effective LAB using cell models and metabolites, optimizing LAB intake through dose-effect studies, enhancing utilization through nanoencapsulation and microencapsulation, investigating mechanisms to deepen the understanding of LAB, and refining clinical study designs. These efforts aim to contribute to comprehending the epidemic trend, pathogenesis, and treatment of IBD, ultimately fostering the development of targeted therapeutic products, such as LAB-based interventions.

Fermentation of Rice, Oat, and Wheat Flour by Pure Cultures of Common Starter Lactic Acid Bacteria: Growth Dynamics, Sensory Evaluation, and Functional Properties

Recent consumer demand for non-dairy alternatives has forced many manufacturers to turn their attention to cereal-based non-alcoholic fermented products. In contrast to fermented dairy products, there is no defined and standardized starter culture for manufacturing cereal-based products. Since spontaneous fermentation is rarely suitable for large-scale commercial production, it is not surprising that manufacturers have started to adopt centuries-known dairy starters based on lactic acid bacteria (LABs) for the fermentation of cereals. However, little is known about the fermentation processes of cereals with these starters. In this study, we combined various analytical tools in order to understand how the most common starter cultures of LABs affect the most common types of cereals during fermentation. Specifically, 3% suspensions of rice, oat, and wheat flour were fermented by the pure cultures of 16 LAB strains belonging to five LAB species-Lacticaseibacillus paracasei, Lactobacillus delbrueckii, Lactobacillus helveticus, Streptococcus thermophilus, and Lactococcus lactis. The fermentation process was described in terms of culture growth and changes in the pH, reducing sugars, starch, free proteins, and free phenolic compounds. The organoleptic and rheological features of the obtained fermented products were characterized, and their functional properties, such as their antioxidant capacity and angiotensin-converting enzyme inhibitory activity, were determined.

Exopolysaccharide from Lacticaseibacillus paracasei alleviates gastritis in Helicobacter pylori-infected mice by regulating gastric microbiota

Introduction

Many probiotics have the ability to produce extracellular polysaccharides (EPS). EPS derived from these probiotics has been confirmed to regulate the host intestinal microecological balance and alleviate the symptoms of diseases caused by gastrointestinal microecological imbalance.

Results

Lactic acid bacteria (LAB) strain with good exopolysaccharide (EPS) producing ability, namely, Lacticaseibacillus paracasei ZFM54 (L. paracasei ZFM54) was screened. The fermentation conditions of L. paracasei ZFM54 for EPS production were optimized. The EPS54 was characterized by chemical component and monosaccharide composition determination, UV, FT-IR and NMR spectra analysis. Cango red, SEM, AFM and XRD analysis were conducted to characterize the structure of EPS54. The EPS54 effectively reduced the colonization of Helicobacter pylori to AGS cells and recovered the cell morphology. EPS54 could also effectively alleviate the gastritis in the H. pylori-infected mice by down-regulating the mRNA expression levels of pro-inflammatory cytokines IL-6, IL-8, IL-1β and TNF-α and up-regulating the mRNA expression of inflammatory cytokine IL-10 in gastric cells. EPS54 was also found to be able to positively regulate the structure of gastric microbiota.

Conclusion

The EPS 54 from L. paracasei ZFM54 can alleviate gastritis in H. pylori-infected mice by modulating the gastric microbiota.

Beyond Conventional Meat Preservation: Saddling the Control of Bacteriocin and Lactic Acid Bacteria for Clean Label and Functional Meat Products

Advancements in food science and technology have paved the way for the development of natural antimicrobial compounds to ensure the safety and quality of meat and meat products. Among these compounds, bacteriocin produced by lactic acid bacteria has gained considerable scientific attention for its ability to preserve the healthy properties of meat while preventing spoilage. This natural preservative is seen as a pioneering tool and a potent alternative to chemical preservatives and heat treatment, which can have harmful effects on the nutritional and sensory qualities of meat. Bacteriocin produced by lactic acid bacteria can be used in various forms, including as starter/protective cultures for fermented meats, purified or partially purified forms, loaded in active films/coatings, or established in encapsulate systems. This review delves into the downstream purification schemes of LAB bacteriocin, the elucidation of their characteristics, and their modes of action. Additionally, the application of LAB bacteriocins in meat and meat products is examined in detail. Overall, the use of LAB bacteriocins holds immense potential to inspire innovation in the meat industry, reducing the dependence on harmful chemical additives and minimizing the adverse effects of heat treatment on nutritional and sensory qualities. This review provides a comprehensive understanding of the potential of bacteriocin produced by lactic acid bacteria as a natural and effective meat preservative.

Electrospun Fibers Loaded with Probiotics: Fundamentals, Characterization, and Applications

Increasing demand for safe, efficient, and eco-friendly solutions for pharmaceutical and food industries has led researchers to explore new approaches to bacterial storage. Several advantages make electrospinning (ES) a promising technique for food systems, including simple manufacturing equipment, a relatively low spinning cost, a wide variety of spinnable materials, and a mild process that is easily controlled, which allows continuous fabrication of ultrafine polymeric fibers at submicron or nanoscales without high temperatures or high pressures. This review briefly describes recent advances in the development of electrospun fibers for loading probiotics (PRB) by focusing on ES technology, its efficiency for loading PRB into fibers (viability, digestive stability, growth rate, release, thermal stability, and interactions of fibers with PRB), and the application of PRB-loaded fibers as active packaging (spoilage/microbial control, antioxidant effect, shelf life). Based on the literature reviewed, the incorporation of PRB into electrospun fibers is both feasible and functional. However, several studies have been limited to proof-of-principle experiments and the use of model biological products. It is necessary to conduct further research to establish the industrial applicability of PRB-loaded fibers, particularly in the fields of food and medicine.

Metagenomics reveals differences in the composition of bacterial antimicrobial resistance and antibiotic resistance genes in pasteurized yogurt and probiotic bacteria yogurt from China

Antimicrobial resistance has become a global public health concern, and antibiotic resistance genes (ARG) in food are a research focus. In China, probiotics and pasteurized yogurts are the 2 main types of commercially available yogurt, but the distribution and differences of antibiotic-resistant bacteria and gene types in these products are not well known. This study used a shotgun metagenomic approach to analyze 22 different types of yogurt collected from 9 main yogurt-producing areas in China; each type of yogurt included 8 different batches of samples. The abundance and diversity of bacteria identified in probiotic yogurt were significantly higher than those in pasteurized yogurt, with Acetobacter, Raoultella, and Burkholderia identified as unique and highly abundant genera in probiotic yogurt. Similarly, the abundance of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. was higher than that in pasteurized yogurt. A total of 1,149 ARG subtypes belonging to 16 ARG types were identified, with the highest abundance of rifampicin, multidrug efflux pumps, and quinolone resistance genes detected. Network analysis revealed significant nonrandom co-occurrence relationships between different types and subtypes of ARG in yogurt samples. A total of 44 ARG subtypes in pasteurized yogurt were potentially hosted by 36 bacterial genera, and in probiotic yogurt, 63 ARG were expected to be hosted by 86 bacterial species from 37 genera. These findings indicate potential safety issues in fermented dairy products and emphasize the need for a more hygienic environment when processing probiotic yogurt.

Immunomodulatory Activity on Human Macrophages by Cell-Free Supernatants to Explore the Probiotic and Postbiotic Potential of Lactiplantibacillus plantarum Strains of Plant Origin

Upon dietary administration, probiotic microorganisms can reach as live cells the human gut, where they interact with the microbiota and host cells, thereby exerting a beneficial impact on host functions, mainly through immune-modulatory activities. Recently, attention has been drawn by postbiotics, i.e. non-viable probiotic microbes, including their metabolic products, which possess biological activities that benefit the host. Lactiplantibacillus plantarum is a bacterial species that comprises recognised probiotic strains. In this study, we investigated in vitro the probiotic (and postbiotic) potential of seven L. plantarum strains, including five newly isolated from plant-related niches. The strains were shown to possess some basic probiotic attributes, including tolerance to the gastrointestinal environment, adhesion to the intestinal epithelium and safety. Besides, their cell-free culture supernatants modulated cytokine patterns in human macrophages in vitro, promoting TNF-α gene transcription and secretion, while attenuating the transcriptional activation and secretion of both TNF-α and IL-8 in response to a pro-inflammatory signal, and enhancing the production of IL-10. Some strains induced a high IL-10/IL-12 ratio that may correlate to an anti-inflammatory capacity in vivo. Overall, the investigated strains are good probiotic candidates, whose postbiotic fraction exhibits immunomodulatory properties that need further in vivo studies. The main novelty of this work consists in the polyphasic characterisation of candidate beneficial L. plantarum strains obtained from relatively atypical plant-associated niches, by an approach that explores both probiotic and postbiotic potentials, in particular studying the effect of microbial culture-conditioned media on cytokine pattern, analysed at both transcriptional and secretion level in human macrophages.

A Response Surface Methodological Approach for Large-Scale Production of Antibacterials from Lactiplantibacillus plantarum with Potential Utility against Foodborne and Orthopedic Infections

A variety of bacteria, including beneficial probiotic lactobacilli, produce antibacterials to kill competing bacteria. Lactobacilli secrete antimicrobial peptides (AMPs) called bacteriocins and organic acids. In the food industry, bacteriocins, but even whole cell-free supernatants, are becoming more and more important as bio-preservatives, while, in orthopedics, bacteriocins are introducing new perspectives in biomaterials technologies for anti-infective surfaces. Studies are focusing on Lactiplantibacillus plantarum (previously known as Lactobacillus plantarum). L. plantarum exhibits great phenotypic versatility, which enhances the chances for its industrial exploitation. Importantly, more than other lactobacilli, it relies on AMPs for its antibacterial activity. In this study, Response Surface Methodology (RSM) through a Box-Behnken experimental design was used to estimate the optimal conditions for the production of antibacterials by L. plantarum. A temperature of 35 °C, pH 6.5, and an incubation time of 48 h provided the highest concentration of antibacterials. The initial pH was the main factor influencing the production of antibacterials, at 95% confidence level. Thanks to RSM, the titer of antibacterials increased more than 10-fold, this result being markedly higher than those obtained in the very few studies that have so far used similar statistical methodologies. The Box-Behnken design turned out to be a valid model to satisfactorily plan a large-scale production of antibacterials from L. plantarum.

Impact of Lactic Acid Bacteria Fermentation on (Poly)Phenolic Profile and In Vitro Antioxidant and Anti-Inflammatory Properties of Herbal Infusions

Recently, the development of functional beverages has been enhanced to promote health and nutritional well-being. Thus, the fermentation of plant foods with lactic acid bacteria can enhance their antioxidant capacity and others like anti-inflammatory activity, which may depend on the variations in the total content and profile of (poly)phenols. The present study aimed to investigate the impact of fermentation with two strains of Lactiplantibacillus plantarum of several herbal infusions from thyme, rosemary, echinacea, and pomegranate peel on the (poly)phenolic composition and whether lacto-fermentation can contribute to enhance their in vitro antioxidant and anti-inflammatory effects on human colon myofibroblast CCD18-Co cells. HPLC-MS/MS analyses revealed that fermentation increased the content of the phenolics present in all herbal infusions. In vitro analyses indicated that pomegranate infusion showed higher antioxidant and anti-inflammatory effects, followed by thyme, echinacea, and rosemary, based on the total phenolic content. After fermentation, despite increasing the content of phenolics, the antioxidant and anti-inflammatory effects via reduction pro-inflammatory markers (IL-6, IL-8 and PGE2) were similar to those of their corresponding non-fermented infusions, with the exception of a greater reduction in lacto-fermented thyme. Overall, the findings suggest that the consumption of lacto-fermented herbal infusions could be beneficial in alleviating intestinal inflammatory disorders.

Highly active probiotic hydrogels matrixed on bacterial EPS accelerate wound healing via maintaining stable skin microbiota and reducing inflammation

Skin microbiota plays an important role in wound healing, but skin injuries are highly susceptible to wound infections, leading to disruption of the skin microbiota. However, conventional antibacterial hydrogels eliminate both probiotics and pathogenic bacteria, disrupting the balance of the skin microbiota. Therefore, it is important to develop a wound dressing that can fend off foreign pathogenic bacteria while preserving skin microbiota stability. Inspired by live bacteria therapy, we designed a probiotic hydrogel (HAEPS@L.sei gel) with high viability for promoting wound healing. Lactobacillus paracasei TYM202 encapsulated in the hydrogel has the activity of promoting wound healing, and the hydrogel matrix EPS-M76 has the prebiotic activity that promotes the proliferation and metabolism of Lactobacillus paracasei TYM202. During the wound healing process, HAEPS@L.sei gel releases lactic acid and acetic acid to resist the growth of pathogenic bacteria while maintaining Firmicutes and Proteobacteria balance at the phylum level, thus preserving skin microbiota stability. Our results showed that live probiotic hydrogels reduce the incidence of inflammation during wound healing while promoting angiogenesis and increasing collagen deposition. This study provides new ideas for developing wound dressings predicated on live bacterial hydrogels.

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.

Reformulation of Tunisian Sun-Dried Merguez with Camel Meat: Characterization of Physicochemical and Compositional Changes in Organic Acids, Fatty Acids, Volatile Compounds, and Minerals

Traditional sun-dried merguez is an authentic Tunisian dried sausage made with a large number of spices and herbs, which was reformulated in this study with camel meat and hump fat and dried as in the artisanal process. This research studied the physicochemical, microbiological, and chemical compositional changes that occurred in fresh camel merguez (FCM) after 12 days of drying to achieve traditional dried camel merguez (DCM). The results showed significant weight loss (54.1%), as well as significant decreases in pH (5.20-4.97), moisture (60.5-12.3%), and water activity (0.986-0.673). These results and the acceptable microbiological quality of DCM can explain the safety of traditionally practiced long-term storage at room temperature. All chemical compositions increased upon drying. The composition of DCM included several organic acids, mainly lactate (2820 mg.kg-1); diverse unsaturated fatty acids, in particular oleic acid (33.2%); and various minerals, specifically iron (8 mg per 100 g), in addition to volatile compounds impacted by herbs and spices rich in terpenes (56.3%). These results can be useful for investing in indigenous products and promoting the exploitation of camel meat.

Current situation, trend, and prospects of research on functional components from by-products of baijiu production: A review

In the present scenario marked by energy source shortages and escalating concerns regarding carbon dioxide emissions, there is a growing emphasis on the optimal utilization of biomass resources. Baijiu, as the Chinese national spirit, boasts remarkably high sales volumes annually. However, the production of baijiu yields various by-products, including solid residues (Jiuzao), liquid wastewater (Huangshui and waste alcohol), and gaseous waste. Recent years have witnessed dedicated research aimed at exploring the composition and potential applications of these by-products, seeking sustainable development and comprehensive resource utilization. This review systematically summarizes recent research, shedding light on both the baijiu brewing process and the bioactive compounds present baijiu production by-products (BPBPs). The primary focus lies in elucidating the potential extraction methods and applications of BPBPs, offering a practical approach to comprehensive utilization of by-products in functional food, medicine, cosmetic, and packaging fields. These applications not only contribute to enhancing production efficiency and mitigating environmental pollution, but also introduce innovative concepts for the sustainable advancement of associated industries. Future research avenues may include more in-depth compositional analysis, the development of utilization technologies, and the promotion of potential industrialization.

The effect of sourdough, turnips, and butternut squash on the physicochemical and nutritional properties of Doowina functional food during fermentation

The dairy-cereal-based food, known as Doowina, is one of the traditional fermented foods in Iran. We aimed to improve the health-promoting properties of Doowina by using turnips, butternut squash, and sourdough as a new functional food with high nutritional value and antioxidant activity. Therefore, the physicochemical, microbial, and sensory properties of samples with nutritional supplements (8% turnip and 8% butternut squash) and different concentrations of sourdough (0, 0.5, and 1%) were studied during 0, 3, 6, and 9 days of fermentation time. The results showed that there was no significant difference (p < .05) in the moisture and ash content between the different formulations of Doowina. There was also no significant difference (p < .05) in the phenolic compound content and antioxidant activity of the Doowina samples during the fermentation period. However, the number of lactic acid bacteria (LAB) increased significantly (p < .05) until the 6th day of fermentation, and the protein content decreased significantly (p < .05) in all samples during the fermentation period. According to the results, the samples with butternut squash and sourdough had the highest total phenolic content, the highest antioxidant activity, the highest linoleic acid content, and the highest sensory rating of all samples.

Comprehensive Review on the Biocontrol of Listeria monocytogenes in Food Products

Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a group of human illnesses that appear more frequently in countries with better-developed food supply systems. This review discusses the efficacy of actual biocontrol methods combined with the main types of food involved in illnesses. Comments on bacteriophages, lactic acid bacteria, bacteriocins, essential oils, and endolysins and derivatives, as main biological antilisterial agents, are made bearing in mind that, using them, food processors can intervene to protect consumers. Both commercially available antilisterial products and solutions presented in scientific papers for mitigating the risk of contamination are emphasized. Potential combinations between different types of antilisterial agents are highlighted for their synergic effects (bacteriocins and essential oils, phages and bacteriocins, lactic acid bacteria with natural or synthetic preservatives, etc.). The possibility to use various antilisterial biological agents in active packaging is also presented to reveal the diversity of means that food processors may adopt to assure the safety of their products. Integrating biocontrol solutions into food processing practices can proactively prevent outbreaks and reduce the occurrences of L. monocytogenes-related illnesses.

Fermented foods, their microbiome and its potential in boosting human health

Fermented foods (FFs) are part of the cultural heritage of several populations, and their production dates back 8000 years. Over the last ~150 years, the microbial consortia of many of the most widespread FFs have been characterised, leading in some instances to the standardisation of their production. Nevertheless, limited knowledge exists about the microbial communities of local and traditional FFs and their possible effects on human health. Recent findings suggest they might be a valuable source of novel probiotic strains, enriched in nutrients and highly sustainable for the environment. Despite the increasing number of observational studies and randomised controlled trials, it still remains unclear whether and how regular FF consumption is linked with health outcomes and enrichment of the gut microbiome in health-associated species. This review aims to sum up the knowledge about traditional FFs and their associated microbiomes, outlining the role of fermentation with respect to boosting nutritional profiles and attempting to establish a link between FF consumption and health-beneficial outcomes.

Fusarium biocontrol: antagonism and mycotoxin elimination by lactic acid bacteria

Mycotoxins produced by Fusarium species are secondary metabolites with low molecular weight formed by filamentous fungi generally resistant to different environmental factors and, therefore, undergo slow degradation. Contamination by Fusarium mycotoxins in cereals and millets is the foremost quality challenge the food and feed industry faces across the globe. Several types of chemical preservatives are employed in the mitigation process of these mycotoxins, and they help in long-term storage; however, chemical preservatives can be used only to some extent, so the complete elimination of toxins from foods is still a herculean task. The growing demand for green-labeled food drives to evade the use of chemicals in the production processes is getting much demand. Thus, the biocontrol of food toxins is important in the developing food sector. Fusarium mycotoxins are world-spread contaminants naturally occurring in commodities, food, and feed. The major mycotoxins Fusarium species produce are deoxynivalenol, fumonisins, zearalenone, and T2/HT2 toxins. Lactic acid bacteria (LAB), generally regarded as safe (GRAS), is a well-explored bacterial community in food preparations and preservation for ages. Recent research suggests that LAB are the best choice for extenuating Fusarium mycotoxins. Apart from Fusarium mycotoxins, this review focuses on the latest studies on the mechanisms of how LAB effectively detoxify and remove these mycotoxins through their various bioactive molecules and background information of these molecules.

Complete genome sequences of Lactococcus lactis D1_2, a bacterium with antimicrobial properties isolated from peat soil

Lactococcus lactis is a beneficial lactic acid bacterium commonly studied for its probiotic properties and role in dairy production. Here, we present a complete genome of Lactococcus lactis D1_2, isolated from peat swamp forests. To discover the potential antimicrobial properties, the complete genome of the strain was sequenced and analyzed.