Health Benefits of Consuming Foods with Bacterial Probiotics, Postbiotics, and Their Metabolites: A Review

Highly Potent New Probiotic Strains from Traditional Turkish Fermented Foods

Traditional Turkish fermented foods like boza, pickles, and tarhana are recognized for their nutritional and health benefits, yet the probiotic potential of lactic acid bacteria (LAB) strains isolated from them remains underexplored. Sixty-six LAB strains were isolated from fermented foods using bacterial morphology, Gram staining, and catalase activity. The isolates were differentiated at strain level by RAPD-PCR (Random Amplification of Polymorphic DNA-Polymerase Chain Reaction) and twenty-five strains were selected for further evaluation of acid and bile salt tolerance. Among these, ten strains exhibited high tolerance and were subsequently assessed for adhesion to Caco-2 colorectal carcinoma cells, antimicrobial activity, exopolysaccharide (EPS) production, lysozyme resistance, and hemolytic activity. Using k-means clustering, three strains: Lactiplantibacillus plantarum ES-3, Pediococcus pentosaceus N-1, and Enterococcus faecium N-2 demonstrated superior probiotic characteristics, including significant acid (100% survival at pH3.0) and 0.3% bile salt tolerance (57%, 64%, 67%), strong adhesion to intestinal cells (65%, 88%, 91%), high lysozyme resistance (88%, 88%, 77%), and produced high amounts of EPS. These strains show promising potential as probiotics and warrant further investigation to confirm their functional properties and potential applications.

Gut microbiota in Alzheimer's disease: Understanding molecular pathways and potential therapeutic perspectives

Accumulating evidence suggests that gut microbiota (GM) plays a crucial role in Alzheimer's disease (AD) pathogenesis and progression. This narrative review explores the complex interplay between GM, the immune system, and the central nervous system in AD. We discuss mechanisms through which GM dysbiosis can compromise intestinal barrier integrity, enabling pro-inflammatory molecules and metabolites to enter systemic circulation and the brain, potentially contributing to AD hallmarks. Additionally, we examine other pathophysiological mechanisms by which GM may influence AD risk, including the production of short-chain fatty acids, secondary bile acids, and tryptophan metabolites. The role of the vagus nerve in gut-brain communication is also addressed. We highlight potential therapeutic implications of targeting GM in AD, focusing on antibiotics, probiotics, prebiotics, postbiotics, phytochemicals, and fecal microbiota transplantation. While preclinical studies showed promise, clinical evidence remains limited and inconsistent. We critically assess clinical trials, emphasizing challenges in translating GM-based therapies to AD patients. The reviewed evidence underscores the need for further research to elucidate precise molecular mechanisms linking GM to AD and determine whether GM dysbiosis is a contributing factor or consequence of AD pathology. Future studies should focus on large-scale clinical trials to validate GM-based interventions' efficacy and safety in AD.

Physicochemical, Antioxidant Characteristics and Sensory Evaluation of Functional Pro-Biogenic Ice Cream

Pro-biogenic is a recent terminology widely used for products that combine biogenic materials and probiotics which has made progressive improvement in a new era of research on functional foods. This study aimed to develop functional ice cream with Bacillus coagulans and propolis extract (PE) as a biogenic part to develop ice cream's physiochemical and antioxidant characteristics. Five probiotic ice cream samples were prepared using different levels of PE powder (0%, 0.2%, 0.4%, 0.6%, and 0.8% w/w), and the physicochemical, total phenol content (TPC), antioxidant and sensory properties, and probiotic survival of the samples were examined. The study found that PE levels did not significantly impact fat, protein, carbohydrate, and ash content, overrun, melting rate, and adhesiveness of probiotic ice cream, but increased dry matter, apparent viscosity, and hardness. Adding PE to freeze-storage samples significantly (p < 0.05) reduced pH and improved TPC and antioxidant activity. The prepared ice cream containing probiotic bacteria and PE extracts, despite their darker and yellower color, were acceptable based on sensory evaluation. Furthermore, the survival of probiotic bacteria in the ice cream, with different levels of PE appeared to be in acceptable limits (107 CFU/g). The findings of the research indicated that the pro-biogenic ice cream has good functionality and incorporating a PE aside probiotic could improve physiochemical and antioxidant characteristics which can be used as a value-added ingredient in the formulation of functional pro-biogenic ice creams.

Antioxidant and Antimicrobial Properties of Probiotics: Insights from In Vitro Assays

Probiotics are microorganisms that provide health benefits at adequate doses and exhibit notable antioxidant and antimicrobial activities. These properties play crucial roles in combating chronic diseases linked to oxidative stress and antimicrobial resistance. This review aimed to summarize the antioxidant and antimicrobial properties of probiotics determined in in vitro studies and discuss mechanistic actions and analysis methods. The MEDLINE (PubMed), Web of Science, Scopus, Science Direct, and Embase databases were utilized. The included articles demonstrated the antioxidant and antimicrobial activities of both isolated and food matrix-associated probiotics, with the most common genera being Lactobacillus, Bifidobacterium, Saccharomyces, and Streptococcus. Antioxidant activity was the most studied property, yielding varied results attributed to evaluation tests and probiotic strain. Antibacterial activity was consistently reported in all studies. Additionally, fermentation with probiotic microorganisms improved the content and bioaccessibility of bioactive compounds. In conclusion, analysis results highlight the antioxidant and antimicrobial activity of probiotics reported in in vitro studies. They enhance bioactive content and bioaccessibility and produce novel beneficial metabolites during fermentation. These results reinforce the therapeutic promise of probiotics associated with plant matrices and indicate the need for clinical studies to confirm their efficacy in improving human health.

The relationship between carbohydrate intake and sleep patterns

Background

A healthy dietary habit may contribute to good sleep quality. The present study investigates the correlation between the quality and quantity of daily carbohydrate consumption and poor sleep patterns.

Methods

The exposures of interest included low-and high-quality carbohydrate consumption and total daily carbohydrate consumption. Subjects were classified into four different carbohydrate consumption patterns: Pattern 1 was characterized by high-quality carbohydrates below the median and low-quality carbohydrates above the median; Pattern 2 included both high-and low-quality carbohydrates below the median; Pattern 3 was defined as high-and low-quality carbohydrates above the median; Pattern 4 referred to high-quality carbohydrates above the median and low-quality carbohydrates below the median. The comprehensive sleep patterns included three different sleep behaviors: sleep duration, daytime sleepiness, and snoring, which were used to score sleep patterns. A score ranging from 0 to 1 was classified as having a healthy sleep pattern, while a score between 2 and 3 showed poor sleep patterns. Survey-weighted multivariable logistic regression analyses were adopted.

Results

In the multivariate analysis, individuals who consumed more high-quality carbohydrates were linked to a decreased likelihood of experiencing poor sleep patterns [odds ratio (OR) 0.71; 95% confidence interval (CI) 0.62-0.81], while increased consumption of low-quality carbohydrates (OR 1.39; 95%CI 1.20-1.61) and total daily carbohydrates (OR 1.31; 95%CI 1.10-1.57) was related to an elevated risk of poor sleep patterns. Participants who adhered to carbohydrate intake pattern 4 exhibited a 36% lower risk of poor sleep patterns than those who followed carbohydrate intake pattern 1 (OR 0.64; 95%CI 0.56-0.74). There was a positive correlation between elevated added sugar consumption and an increased probability of developing poor sleep patterns. In contrast, an elevated intake of whole grains, fruits, or non-starchy vegetables was related to a decreased likelihood of experiencing poor sleep patterns.

Conclusion

The increased consumption of low-quality carbohydrates may heighten the susceptibility to poor sleep patterns, whereas the increased consumption of high-quality carbohydrates may mitigate the risk of developing poor sleep patterns.

Microalgae and cyanobacteria as microbial substrate and their influence on the potential postbiotic capability of a bacterial probiotic

Postbiotics are metabolic by-products from microorganisms that provide health benefits to the host. Their secretion can be influenced by various conditions affecting bacterial metabolism. This study presents a novel approach for producing potential postbiotics, specifically extracellular products (ECPs), from the probiotic strain Shewanella putrefaciens SpPdp11, grown under different culture conditions. These conditions include aquafeed media, with partial or total microalgae/cyanobacteria replacement as the microbial substrate, as well as variations in temperature and growth phase. The use of microalgae/cyanobacteria as substrates may represent a valuable strategy for generating novel postbiotics with unique properties. The ECPs assessed were evaluated for their in vitro cytotoxic, hydrolytic and antimicrobial activities. Three conditions (ECPs derived from aquafeed media with partial (FM2324 and FM1548) or total (M2324) microalgae/cyanobacteria replacement) were non-cytotoxic to various fish cell lines and hydrolysed key nutritional compounds (casein, lipids, amylase and gelatin). Proteomic analysis of these ECP conditions revealed common structural and regulatory DNA-associated proteins, while differentially expressed proteins were associated with amino acid metabolism and antioxidant system (FM2324 and FM1548) and chemotaxis system (M2324). The results highlight the potential of the selected postbiotics as feed additives for future in vivo studies, aligning with sustainable development for aquaculture.

Limosilactobacillus reuteri DSM 17938 relieves inflammation, endoplasmic reticulum stress, and autophagy in hippocampus of western diet-fed rats by modulation of systemic inflammation

The consumption of western diets, high in fats and sugars, is a crucial contributor to brain molecular alterations, cognitive dysfunction and neurodegenerative diseases. Therefore, a mandatory challenge is the individuation of strategies capable of preventing diet-induced impairment of brain physiology. A promising strategy might consist in the administration of probiotics that are known to influence brain function via the gut-brain axis. In this study, we explored whether Limosilactobacillus reuteri DSM 17938 (L. reuteri)-based approach can counteract diet-induced neuroinflammation, endoplasmic reticulum stress (ERS), and autophagy in hippocampus, an area involved in learning and memory, in rat fed a high fat and fructose diet. The western diet induced a microbiota reshaping, but L. reuteri neither modulated this change, nor the plasma levels of short-chain fatty acids. Interestingly, pro-inflammatory signaling pathway activation (increased NFkB phosphorylation, raised amounts of toll-like receptor-4, tumor necrosis factor-alpha, interleukin-6, GFAP, and Haptoglobin), as well as activation of ERS (increased PERK and eif2α phosphorylation, higher C/EBP-homologous protein amounts) and autophagy (increased beclin, P62-sequestosome-1, and LC3 II) was revealed in hippocampus of western diet fed rats. All these hippocampal alterations were prevented by L. reuteri administration, showing for the first time a neuroprotective role of this specific probiotic strain, mainly attributable to its ability to regulate western diet-induced metabolic endotoxemia and systemic inflammation, as decreased levels of lipopolysaccharide, plasma cytokines, and adipokines were also found. Therapeutic strategies based on the use of L. reuteri DSM17938 could be beneficial in reversing metabolic syndrome-mediated brain dysfunction and cognitive decline.

Whole-Genome Sequencing of Three Lactiplantibacillus plantarum Strains Reveals Potential Metabolites for Boosting Host Immunity Safely

In response to the growing demand for immune-related products, this study evaluated the safety and immune-modulating potential of three newly discovered Lactiplantibacillus plantarum strains (GKM3, GKK1, and GKD7) through toxicity tests and whole-genome sequencing. Safety evaluations, including the analysis of antimicrobial resistance genes, virulence factors, plasmids, and prophages, classified these strains as safe for human consumption. Acute oral toxicity tests further supported their safety. To evaluate their immune-modulating potential, dendritic cells were exposed to these strains, and the secretion of key cytokines (IFN-β and IL-12) was measured. Among the strains, GKK1 exhibited the highest enhancement of IFN-β and IL-12 production, suggesting its potential as an immune-stimulating probiotic. Bioinformatics analysis revealed potential metabolic pathways and secondary metabolites, including predicted bacteriocins, associated with immune modulation. The presence of a nitrate reductase region in the GKK1 strain indicated its ability to produce nitric oxide, a critical molecule involved in immune regulation and host defense. The presence of glucorhamnan-related gene clusters in GKK1 also suggested immune-enhancing effects. Nitrate reductase expression was confirmed using qPCR, with the highest levels detected in GKK1. Moreover, this study is the first to show an anti-inflammatory effect of plantaricin A, linked to its presence in strain GKM3 and its potential therapeutic applications due to sequence similarity to known anti-inflammatory peptides. Overall, these three L. plantarum strains demonstrated a safe profile and GKK1 showed potential as an immunity-enhancing probiotic. However, additional investigation is required to confirm the involvement of specific metabolic pathways, secondary metabolites, and bacteriocins in immune responses.

Comparative Efficacy of Parenteral and Mucosal Recombinant Probiotic Vaccines Against SARS-CoV-2 and S. pneumoniae Infections in Animal Models

BACKGROUND

The accumulation of specific IgG antibodies in blood serum is considered a key criterion for the effectiveness of vaccination. For several vaccine-preventable infections, quantitative indicators of the humoral response have been established, which, when reached, provide a high probability of protection against infection. The presence of such a formal correlate of vaccine effectiveness is crucial, for example, in organizing preventive measures and validating newly developed vaccines. However, can effective protection against infection occur when the level of serum antibodies is lower than that provided by parenteral vaccination? Will protection be sufficient if the same vaccine antigen is administered via mucosal membranes without achieving high levels of specific IgG circulating in the blood?

METHODS

In this study, we compared the immunogenicity and protective efficacy of parenteral and mucosal forms of vaccines in experimental animals, targeting infections caused by the SARS-CoV-2 coronavirus and Streptococcus pneumoniae. We investigated the protective properties of a fragment of the coronavirus S1 protein administered intramuscularly with an adjuvant and orally as part of the probiotic strain Enterococcus faecium L3 in a Syrian hamster model. A comparative assessment of the immunogenicity and protective efficacy of a recombinant tandem (PSP) of immunogenic peptides from S. pneumoniae surface proteins, administered either parenterally or orally, was performed in a Balb/c mouse model.

RESULTS

Both models demonstrated significant differences in the immunogenicity of parenteral and oral vaccine antigens, but comparable protective efficacy.

Prebiotics enhance the immunomodulatory effect of Limosilactobacillus fermentum DALI02 by regulating intestinal homeostasis

The colonization ability of Limosilactobacillus fermentum DALI02 and the promoting effect of fermented prebiotics have been studied. This study aims to evaluate the systemic immunomodulatory effects of DALI02 and DALI02 + Prebiotics on cyclophosphamide-induced immunosuppressed rats. We found that DALI02 and DALI02 + Prebiotics, especially DALI02 + Prebiotics, exhibited significant restorative effects on the immunocompromised state in rats (p < .05). Specifically, both of them promoted the recovery of body weight and immune organ function, enhanced the proliferative capacity of immune cells, and effectively reduced the levels of interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α). Furthermore, both of them significantly reduced the levels of lipopolysaccharide (LPS) and D-lactic acid in the blood (p < .05). Principal coordinate analysis (PCoA), principal component analysis (PCA), and unsupervised cluster analysis revealed that DALI02 and DALI02 + Prebiotics group were more similar to the blank group at the genus level of the gut microbiota. At the level of short-chain fatty acids (SCFAs), DALI02 + Prebiotics and blank group belonged to Cluster 3. These results suggested that the intervention with DALI02 and DALI02 + Prebiotics effectively modulated the structure of the gut microbiota, and DALI02 + Prebiotics restored the dysregulation of SCFAs. In summary, DALI02 and DALI02 + Prebiotics possess immunomodulatory functions, with the latter showing superior effects.

Nutrient consumption patterns of Lactobacillus acidophilus

BACKGROUND

One of the greatest challenges in using Lactobacillus acidophilus as a probiotic is acid stress. The current research aimed to identify substances that help L. acidophilus resist acid stress; this was achieved through assessing its nutrient consumption patterns under various pH conditions.

RESULTS

The consumption rates of alanine, uracil, adenine, guanine, niacin, and manganese were consistently higher than 60% for L. acidophilus LA-5 cultured at pH 5.8, 4.9, and 4.4. The consumption rates of glutamic acid + glutamine and thiamine increased with decreasing pH and were higher than 60% at pH 4.9 and 4.4. The viable counts of L. acidophilus LA-5 were significantly increased under the corresponding acidic stress conditions (pH 4.9 and 4.4) through the appropriate addition of either alanine (3.37 and 2.81 mmol L-1), glutamic acid + glutamine (4.77 mmol L-1), guanine (0.13 and 0.17 mmol L-1), niacin (0.02 mmol L-1), thiamine (0.009 mmol L-1), or manganese (0.73 and 0.64 mmol L-1) (P < 0.05). The viable counts of L. acidophilus LA-5 cultured in a medium supplemented with combined nutritional factors was 1.02-1.03-fold of the counts observed in control medium under all acid conditions (P < 0.05).

CONCLUSION

Alanine, glutamic acid + glutamine, guanine, niacin, thiamine, and manganese can improve the growth of L. acidophilus LA-5 in an acidic environment in the present study. The results will contribute to optimizing strategies to enhance the acid resistance of L. acidophilus and expand its application in the fermentation industry. © 2024 Society of Chemical Industry.

Exploring the Potential of Postbiotics for Food Safety and Human Health Improvement

Food safety is a global concern, with millions suffering from foodborne diseases annually. The World Health Organization (WHO) reports significant morbidity and mortality associated with contaminated food consumption, and this emphasizes the critical need for comprehensive food safety measures. Recent attention has turned to postbiotics, metabolic byproducts of probiotics, as potential agents for enhancing food safety. Postbiotics, including organic acids, enzymes, and bacteriocins, exhibit antimicrobial and antioxidant properties that do not require live organisms, and this offers advantages over probiotics. This literature review critically examines the role of postbiotics in gut microbiome modulation and applications in the food industry. Through an extensive review of existing literature, this study evaluates the impact of postbiotics on gut microbiome composition and their potential as functional food ingredients. Research indicates that postbiotics are effective in inhibiting food pathogens such as Staphylococcus aureus, Salmonella enterica, and Escherichia coli, as well as their ability to prevent oxidative stress-related diseases, and they also show promise as alternatives to conventional food preservatives that can extend food shelf life by inhibiting harmful bacterial growth. Their application in functional foods contributes to improved gut health and reduced risk of foodborne illnesses. Findings suggest that postbiotics hold promise for improving health and preservation by inhibiting pathogenic bacteria growth and modulating immune responses.

Probiotic Functions in Fermented Foods: Anti-Viral, Immunomodulatory, and Anti-Cancer Benefits

Fermented foods can provide many benefits to our health. These foods are created by the action of microorganisms and help support our digestive health and immune system. Fermented foods include yogurt, kimchi, pickles, kefir, beer, wine, and more. Fermented foods contain probiotics, lactic acid bacteria (LAB), yeast, organic acids, ethanol, or antimicrobial compounds, which help balance the gut microbiome and improve digestive health. Fermented foods can also benefit your overall health by increasing the diversity of your gut microbiome and reducing inflammation. By routinely consuming fermented foods with these benefits, we can continue to improve our health. Probiotics from fermented foods are beneficial strains of bacteria that are safe for human health and constitute an important component of human health, even for children and the elderly. Probiotics can have a positive impact on your health, especially by helping to balance your gut microbiome and improve digestive health. Probiotics can also boost your immune system and reduce inflammation, which can benefit your overall health. Probiotics, which can be consumed in the diet or in supplement form, are found in many different types of foods and beverages. Research is continuing to investigate the health effects of probiotics and how they can be utilized. The potential mechanisms of probiotics include anti-cancer activity, preventing and treating immune system-related diseases, and slowing the development of Alzheimer's disease and Huntington's disease. This is due to the gut-brain axis of probiotics, which provides a range of health benefits beyond the digestive and gastrointestinal systems. Probiotics reduce tumor necrosis factor-α and interleukins through the nuclear factor-kappa B and mitogen-activated protein kinase pathways. They have been shown to protect against colon cancer and colitis by interfering with the adhesion of harmful bacteria in the gut. This article is based on clinical and review studies identified in the electronic databases PubMed, Web of Science, Embase, and Google Scholar, and a systematic review of clinical studies was performed.

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.

Daily Supplementation with Bifidobacterium longum KACC91563 Alleviates Allergic Contact Dermatitis in an Animal Model

Allergic contact dermatitis (ACD) is the most common chronic inflammatory skin disease (or immune-mediated disease), causing disruption to our psychological condition and life quality. In this study, the therapeutic properties of probiotic Bifidobacterium longum (B. longum) was investigated by using an ACD-induced animal model. For ACD induction, BALB/c mice ear and dorsal skin were sensitized with 240 µL of 1% (w/v) 2,4-dinitrochlorobenzene (DNCB) twice (3-day intervals). After a week of the first induction, the mice were re-sensitized by painting on their dorsal skin and ear with 0.4% (w/v) DNCB for a further three times (once per week). Before the ACD induction of 2 weeks and throughout the trial period, the BALB/c mice were supplemented daily with 1 mL of 1.0 × 109 CFU or 5.0 × 109 CFU B. longum using an intragastric gavage method. The ACD-induced mice without B. longum supplementation were used as a control. Results show that B. longum supplementation significantly alleviated ACD symptoms (e.g., ear swelling, epidermal damage) and immune response (e.g., reduced immune cell recruitment, serum IgE level, and cytokine production). The therapeutic efficiency of B. longum increased as the supplementation dose increased. Thus, daily supplementation with 5.0 × 109 CFU probiotic B. longum could be an effective method for the prevention and treatment of ACD.

Relationship between Presentation, Attitude, and In-Flight Meal Food Healthiness: Moderating Role of Familiarity

This work focused on the perception of the food healthiness of in-flight meals. This work adopts presentation as the determinant. This work also employs attitude as the consequence of food healthiness. This research also examines the moderating effect of familiarity on the relationship between food presentation and food healthiness. This research used a survey, and survey participants were recruited via a Clickworker platform service. Survey participants were experienced with in-flight meals. The number of observations was 317. Moreover, this research tested the research hypotheses using the Hayes process macro Model 7. The results revealed that food healthiness is positively influenced by presentation and that food healthiness positively affects attitude. Moreover, the results revealed that the type of presentation has a positive influence on attitude. Familiarity was a significant moderating variable for the relationship between food presentation and food healthiness. This work sheds light on the literature by identifying the associations among four attributes of in-flight meals. Additionally, the results of this study could be used as a reference to develop better in-flight meals.

Anti-inflammatory, antioxidant effects, and antimicrobial effect of Bacillus subtilis P223

This study aimed to investigate the anti-inflammatory, antioxidant, and antimicrobial effects of Bacillus subtilis P223 which is known to have probiotic properties. B. subtilis P223 that had been killed by heat in LPS-induced RAW 264.7 cells decreased nitric oxide (NO) production. Furthermore, it inhibited the expression of proinflammatory cytokines such interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α). Heat-killed B. subtilis P223 also inhibited the expression of the nuclear factor (NF)-κB cellular signaling pathway, and it showed reactive oxygen species (ROS) reduction. In DPPH, ABTS, and SOD assay, B. subtilis P223 showed a high antioxidant capacity, and inhibited the growth of skin related pathogens including Staphylococcus aureus and Propionibacterium acnes. This study therefore demonstrated the various functional properties of B. subtilis P223 as probiotics, and suggested the potential for its application as functional material.

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.

The urinary microbiota composition and functionality of calcium oxalate stone formers

Background

Accumulated evidences indicate that dysbiosis of the urinary microbiota is associated with kidney stone formation. In the present study, we aimed to investigate the urinary microbiota composition and functionality of patients with calcium oxalate stones and compare it with those of healthy individuals.

Method

We collected bladder urine samples from 68 adult patients with calcium oxalate stones and 54 age-matched healthy controls by transurethral catheterization. 16S rRNA gene and shotgun sequencing were utilized to characterize the urinary microbiota and functionality associated with calcium oxalate stones.

Results

After further exclusion, a total of 100 subjects was finally included and analyzed. The diversity of the urinary microbiota in calcium oxalate stone patients was not significantly different from that of healthy controls. However, the urinary microbiota structure of calcium oxalate stone formers significantly differed from that of healthy controls (PERMANOVA, r = 0.026, P = 0.019). Differential representation of bacteria (e.g., Bifidobacterium) and several enriched functional pathways (e.g., threonine biosynthesis) were identified in the urine of calcium oxalate stone patients.

Conclusion

Our results showed significantly different urinary microbiota structure and several enriched functional pathways in calcium oxalate stone patients, which provide new insight into the pathogenesis of calcium oxalate stones.

Unraveling the Puzzle: Health Benefits of Probiotics-A Comprehensive Review

A growing number of probiotic-containing products are on the market, and their use is increasing. Probiotics are thought to support the health of the gut microbiota, which in turn might prevent or delay the onset of gastrointestinal tract disorders. Obesity, type 2 diabetes, autism, osteoporosis, and some immunological illnesses are among the conditions that have been shown to possibly benefit from probiotics. In addition to their ability to favorably affect diseases, probiotics represent a defense system enhancing intestinal, nutritional, and oral health. Depending on the type of microbial strain utilized, probiotics can have variable beneficial properties. Although many microbial species are available, the most widely employed ones are lactic acid bacteria and bifidobacteria. The usefulness of these bacteria is dependent on both their origin and their capacity to promote health. Probiotics represent a valuable clinical tool supporting gastrointestinal health, immune system function, and metabolic balance. When used appropriately, probiotics may provide benefits such as a reduced risk of gastrointestinal disorders, enhanced immunity, and improved metabolic health. Most popular probiotics, their health advantages, and their mode of action are the topic of this narrative review article, aimed to provide the reader with a comprehensive reappraisal of this topic matter.

Clinical trials of probiotics: Current outlook

The current investigation provides a summary of the available clinical trials using probiotics as therapeutic worldwide and their fate.

Microbiome Dynamics: A Paradigm Shift in Combatting Infectious Diseases

Infectious diseases have long posed a significant threat to global health and require constant innovation in treatment approaches. However, recent groundbreaking research has shed light on a previously overlooked player in the pathogenesis of disease-the human microbiome. This review article addresses the intricate relationship between the microbiome and infectious diseases and unravels its role as a crucial mediator of host-pathogen interactions. We explore the remarkable potential of harnessing this dynamic ecosystem to develop innovative treatment strategies that could revolutionize the management of infectious diseases. By exploring the latest advances and emerging trends, this review aims to provide a new perspective on combating infectious diseases by targeting the microbiome.

Milk and Its Derivatives as Sources of Components and Microorganisms with Health-Promoting Properties: Probiotics and Bioactive Peptides

Milk is a source of many valuable nutrients, including minerals, vitamins and proteins, with an important role in adult health. Milk and dairy products naturally containing or with added probiotics have healthy functional food properties. Indeed, probiotic microorganisms, which beneficially affect the host by improving the intestinal microbial balance, are recognized to affect the immune response and other important biological functions. In addition to macronutrients and micronutrients, biologically active peptides (BPAs) have been identified within the amino acid sequences of native milk proteins; hydrolytic reactions, such as those catalyzed by digestive enzymes, result in their release. BPAs directly influence numerous biological pathways evoking behavioral, gastrointestinal, hormonal, immunological, neurological, and nutritional responses. The addition of BPAs to food products or application in drug development could improve consumer health and provide therapeutic strategies for the treatment or prevention of diseases. Herein, we review the scientific literature on probiotics, BPAs in milk and dairy products, with special attention to milk from minor species (buffalo, sheep, camel, yak, donkey, etc.); safety assessment will be also taken into consideration. Finally, recent advances in foodomics to unveil the probiotic role in human health and discover novel active peptide sequences will also be provided.

Gut-Liver Axis as a Therapeutic Target for Drug-Induced Liver Injury

Drug-induced liver injury (DILI) is a liver disease that remains difficult to predict and diagnose, and the underlying mechanisms are yet to be fully clarified. The gut-liver axis refers to the reciprocal interactions between the gut and the liver, and its homeostasis plays a prominent role in maintaining liver health. It has been recently reported that patients and animals with DILI have a disrupted gut-liver axis, involving altered gut microbiota composition, increased intestinal permeability and lipopolysaccharide translocation, decreased short-chain fatty acids production, and impaired bile acid metabolism homeostasis. The present review will summarize the evidence from both clinical and preclinical studies about the role of the gut-liver axis in the pathogenesis of DILI. Moreover, we will focus attention on the potential therapeutic strategies for DILI based on improving gut-liver axis function, including herbs and phytochemicals, probiotics, fecal microbial transplantation, postbiotics, bile acids, and Farnesoid X receptor agonists.

The effect of enterocin A/P dipeptide on growth performance, glutathione-peroxidase activity, IgA secretion and jejunal morphology in rabbits after experimental methicillin-resistant Staphylococcus epidermidis P3Tr2a Infection

The increasing frequency of methicillin-resistant (MR) staphylococci in humans and animals need special attention for their difficult treatment and zoonotic character, therefore novel antimicrobial compounds on a natural base against antibiotic-resistant bacteria are requested. Currently, bacteriocins/enterocins present a new promising way to overcome this problem, both in prevention and treatment. Therefore, the preventive and medicinal effect of dipeptide enterocin EntA/P was evaluated against MR Staphylococcus epidermidis SEP3/Tr2a strain in a rabbit model, testing their influence on growth performance, glutathione-peroxidase (GPx) enzyme activity, phagocytic activity (PA), secretory (s)IgA, and jejunal morphometry (JM). Eighty-eight rabbits (aged 35 days, meat line M91, both sexes) were divided into experimental groups S (SEP3/Tr2a strain; 1.0 × 105 CFU/mL; dose 500µL/animal/day for 7 days, between days 14 and 21 to simulate the pathogen attack), E (EntA/P; 50 µL/animal/day, 25,600 AU/mL in two intervals, for preventive effect between days 0 and 14; for medicinal effect between days 28 and 42), E + S (EntA/P + SEP3/Tr2a; preventive effect; SEP3/Tr2a + EntA/P; medicinal effect) and control group (C; without additives). Higher body weight was recorded in all experimental groups (p < 0.001) compared to control data. The negative influence/attack of the SEP3Tra2 strain on the intestinal immunity and environment was reflected as decreased GPx activity, worse JM parameters and higher sIgA concentration in infected rabbits. These results suggest the promising preventive use of EntA/P to improve the immunity and growth of rabbits, as well as its therapeutic potential and protective role against staphylococcal infections in rabbit breeding.

Complete genome analysis of Bacillus velezensis TS5 and its potential as a probiotic strain in mice

Introduction

In recent years, a large number of studies have shown that Bacillus velezensis has the potential as an animal feed additive, and its potential probiotic properties have been gradually explored.

Methods

In this study, Illumina NovaSeq PE150 and Oxford Nanopore ONT sequencing platforms were used to sequence the genome of Bacillus velezensis TS5, a fiber-degrading strain isolated from Tibetan sheep. To further investigate the potential of B. velezensis TS5 as a probiotic strain, in vivo experiments were conducted using 40 five-week-old male specific pathogen-free C57BL/6J mice. The mice were randomly divided into four groups: high fiber diet control group (H group), high fiber diet probiotics group (HT group), low fiber diet control group (L group), and low fiber diet probiotics group (LT group). The H and HT groups were fed high-fiber diet (30%), while the L and LT groups were fed low-fiber diet (5%). The total bacteria amount in the vegetative forms of B. velezensis TS5 per mouse in the HT and LT groups was 1 × 109 CFU per day, mice in the H and L groups were given the same volume of sterile physiological saline daily by gavage, and the experiment period lasted for 8 weeks.

Results

The complete genome sequencing results of B. velezensis TS5 showed that it contained 3,929,788 nucleotides with a GC content of 46.50%. The strain encoded 3,873 genes that partially related to stress resistance, adhesion, and antioxidants, as well as the production of secondary metabolites, digestive enzymes, and other beneficial nutrients. The genes of this bacterium were mainly involved in carbohydrate metabolism, amino acid metabolism, vitamin and cofactor metabolism, biological process, and molecular function, as revealed by KEGG and GO databases. The results of mouse tests showed that B. velezensis TS5 could improve intestinal digestive enzyme activity, liver antioxidant capacity, small intestine morphology, and cecum microbiota structure in mice.

Conclusion

These findings confirmed the probiotic effects of B. velezensis TS5 isolated from Tibetan sheep feces and provided the theoretical basis for the clinical application and development of new feed additives.

Assessment of Probiotic and Antioxidant Potential of Indigenous Lactobacillus Strains Isolated from Human Faecal Samples

This study aimed to isolate and characterize probiotic Lactobacilli from human faecal samples of Jammu region of India and evaluation of their antioxidative properties. A total of 29 Lactobacillus strains were isolated and tested for their ability to withstand different pH levels, high concentrations of bile salt and lysozyme along with their adhesion ability to different hydrocarbons and auto-aggregation. Selected probiotic Lactobacillus isolates were further examined for their antioxidant potential using ABTS, DPPH methods, and the ability to scavenge superoxide and hydroxyl radicals. The results showed that Lactobacillus LpJ1 (7.93 ± 0.23) and LpJ5 (7.93 ± 0.59) had the highest cell viability at a pH of 2.5, while Lactobacillus LpJ16 (7.91 ± 0.48) had the highest resistance to bile salts. Many of the isolates also demonstrated good tolerance to lysozyme. The adhesion abilities of these isolates were characterized by cell surface hydrophobicity and auto aggregation which ranged between 50.32% to 77.8% and 51.02% to 78.95% respectively. In addition, Lactobacillus LpJ5 and LpJ8 showed excellent antioxidant activity. Based on these findings, the selected probiotic strains could be potential candidates for use in functional food to reduce oxidative stress.

Graphical abstract

Association of dietary live microbe intake with abdominal aortic calcification in US adults: a cross-sectional study of NHANES 2013-2014

OBJECT

To explore the potential association between dietary live microbe intake and abdominal aortic calcification (AAC).

METHODS

We conducted a cross-section study based on the National Health and Nutrition Examination Survey (NHANES). We categorized the participants into three groups (low, medium, and high dietary intake of live microbes) according to Sanders's dietary live microbe classification system and participants' 24-h dietary recall data. AAC was quantified by using dual-energy X-ray absorptiometry (DXA) and diagnosed by using the Kauppila AAC-24 score system. The analyses utilized weighted logistic regression and weighted linear regression.

RESULTS

A total of 2,586 participants were included. After the full adjustment for covariates, compared to participants with a low dietary live microbe intake, participants with a high dietary live microbe intake had a significantly lower risk of severe AAC (OR: 0.39, 95% CI: 0.22, 0.68, p = 0.003), and the AAC score was also significantly decreased (β:-0.53, 95% CI: -0.83, -0.23, p = 0.002).

CONCLUSION

In this study, more dietary live microbial intake was associated with lower AAC scores and a lower risk of severe AAC. However, more research is needed to verify this.

Recent advances in probiotication of fruit and vegetable juices

Probiotics are live bacteria beneficial to health when consumed adequately. Health professionals now recommend probiotics on regular diets due to their positive effects on human health. The probiotics that are usually consumed from the market through food products are mostly dairy-based. Fruit and vegetables are gaining popularity as preferred matrices for probiotic carriers to the human body, owing to their high cholesterol content and the lactose intolerance of dairy products. On the other hand, fruits and vegetable juices are rich in nutrient content such as vitamins, minerals, and antioxidants and do not contain a starter culture that can compete with the nutrients. The probiotication of fruit and vegetable juices (apple, carrot, citrus fruit, pome-granate, watermelon, tomato, and pineapple) are performing as efficient probiotic bacteria carriers. This review covers the previous works that highlighted the variety of probiotic fruit and vegetable juices as well as the viability of each probiotic in various products after proper fermentation and storage. In addition, physicochemical and sensory changes that occurred during the processing and storage period have been discussed. Furthermore, strategies (microencapsulation, adding prebiotics, antioxidant addition, maintaining optimum pH, temperature, adaptation with resistance, and good packaging) to improve the stability of probiotic bacteria are outlined, as it is difficult to maintain the stability of probiotic bacteria during storage. Finally, the manuscript discusses the effect of probiotic fruit and vegetable juices on human health.

Characterization and anti-inflammatory effect of selenium-enriched probiotic Bacillus amyloliquefaciens C-1, a potential postbiotics

A patented strain of Bacillus amyloliquefaciens C-1 in our laboratory could produce functional sodium selenite (Na2SeO3) under optimized fermentation conditions. With the strong stress resistance and abundant secondary metabolites, C-1 showed potential to be developed as selenium-enriched postbiotics. C-1 has the ability to synthesize SeNPs when incubated with 100 μg/ml Na2SeO3 for 30 h at 30 °C aerobically with 10% seeds-culture. The transformation rate from Na2SeO3 into SeNPs reached to 55.51%. After selenium enrichment, there were no significant morphology changes in C-1 cells but obvious SeNPs accumulated inside of cells, observed by scanning electron microscope and transmission electron microscope, verified by energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. SeNPs had antioxidant activity in radical scavenge of superoxide (O2-), Hydroxyl radical (OH-) and 1,1-diphenyl-2-picryl-hydrazine (DPPH), where scavenging ability of OH- is the highest. Selenium-enriched C-1 had obvious anti-inflammatory effect in protecting integrity of Caco-2 cell membrane destroyed by S. typhimurium; it could preventing inflammatory damage in Caco-2 stressed by 200 μM H2O2 for 4 h, with significantly reduced expression of IL-8 (1.687 vs. 3.487, P = 0.01), IL-1β (1.031 vs. 5.000, P < 0.001), TNF-α (2.677 vs. 9.331, P < 0.001), increased Claudin-1 (0.971 vs. 0.611, P < 0.001) and Occludin (0.750 vs. 0.307, P < 0.001). Transcriptome data analysis showed that there were 381 differential genes in the vegetative growth stage and 1674 differential genes in the sporulation stage of C-1 with and without selenium-enrichment. A total of 22 ABC transporter protein-related genes at vegetative stage and 70 ABC transporter protein-related genes at sporulation stage were founded. Genes encoding MsrA, thiol, glutathione and thioredoxin reduction were significantly up-regulated; genes related to ATP synthase such as atpA and atpD genes showed down-regulated during vegetative stage; the flagellar-related genes (flgG, fliM, fliL, and fliJ) showed down-regulated during sporulation stage. The motility, chemotaxis and colonization ability were weakened along with synthesized SeNPs accumulated intracellular at sporulation stage. B. amyloliquefaciens C-1 could convert extracellular selenite into intracellular SeNPs through the oxidation-reduction pathway, with strong selenium-enriched metabolism. The SeNPs and selenium-enriched cells had potential to be developed as nano-selenium biomaterials and selenium-enriched postbiotics.

Exploring probiotic effector molecules and their mode of action in gut-immune interactions

Probiotics, live microorganisms that confer health benefits when consumed in adequate amounts, have gained significant attention for their potential therapeutic applications. The beneficial effects of probiotics are believed to stem from their ability to enhance intestinal barrier function, inhibit pathogens, increase beneficial gut microbes, and modulate immune responses. However, clinical studies investigating the effectiveness of probiotics have yielded conflicting results, potentially due to the wide variety of probiotic species and strains used, the challenges in controlling the desired number of live microorganisms, and the complex interactions between bioactive substances within probiotics. Bacterial cell wall components, known as effector molecules, play a crucial role in mediating the interaction between probiotics and host receptors, leading to the activation of signaling pathways that contribute to the health-promoting effects. Previous reviews have extensively covered different probiotic effector molecules, highlighting their impact on immune homeostasis. Understanding how each probiotic component modulates immune activity at the molecular level may enable the prediction of immunological outcomes in future clinical studies. In this review, we present a comprehensive overview of the structural and immunological features of probiotic effector molecules, focusing primarily on Lactobacillus and Bifidobacterium. We also discuss current gaps and limitations in the field and propose directions for future research to enhance our understanding of probiotic-mediated immunomodulation.

Lactobacillus fermentum HY7302 Improves Dry Eye Symptoms in a Mouse Model of Benzalkonium Chloride-Induced Eye Dysfunction and Human Conjunctiva Epithelial Cells

(1) We investigated the effects of the Lactobacillus fermentum HY7302 (HY7302) in a mouse model of benzalkonium chloride (BAC)-induced dry eye, and the possibility of using HY7302 as a food supplement for preventing dry eye. (2) The ocular surface of Balb/c mice was exposed to 0.2% BAC for 14 days to induce dry eye (n = 8), and the control group was treated with the same amount of saline (n = 8). HY7302 (1 × 10⁹ CFU/kg/day, 14 days, n = 8) was orally administered daily to the mice, and omega-3 (200 mg/kg/day) was used as a positive control. To understand the mechanisms by which HY7302 inhibits BAC-induced dry eye, we performed an in vitro study using a human conjunctival cell line (clone-1-5c-4). (3) The probiotic HY7302 improved the BAC-induced decreases in the corneal fluorescein score and tear break-up time. In addition, the lactic acid bacteria increased tear production and improved the detached epithelium. Moreover, HY7302 lowered the BAC-induced increases in reactive oxygen species production in a conjunctival cell line and regulated the expression of several apoptosis-related factors, including phosphorylated protein kinase B (AKT), B-cell lymphoma protein 2 (Bcl-2), and activated caspase 3. Also, HY7302 alleviated the expression of pro-inflammatory cytokines, such as interleukin-1β (IL-1β), IL-6, and IL-8, and also regulated the matrix metallopeptidase-9 production in the conjunctival cell line. (4) In this study, we showed that L. fermentum HY7302 helps prevent dry eye disease by regulating the expression of pro-inflammatory and apoptotic factors, and could be used as a new functional food composition to prevent dry eye disease.

Effects of Probiotic Saccharomyces boulardii Supernatant on Viability, Nano-Mechanical Properties of Cytoplasmic Membrane and Pro-Inflammatory Gene Expression in Human Gastric Cancer AGS Cells

BACKGROUND

Gastric cancer has been recognized as the second most probable cause of death in humans from cancer diseases around the world. Postbiotics, supernatant, and metabolites from probiotic microorganisms have recently been used widely to prevent and treat cancer diseases in humans, without any undesirable side effects. This study explores the antiproliferative and antitumor activities of the probiotic Saccharomyces cerevisiae var. boulardii supernatant (SBS) against AGS cancer cells, a human gastric adenocarcinoma cell line.

METHODS

We evaluated cell growth inhibitory and mechanical properties of the cytoplasmic membrane and the downregulation of survivin and proinflammatory genes in AGS cells treated with SBS after 24 and 48 h.

RESULTS

SBS significantly inhibits the AGS cell growth, and the concentrations with IC₅₀ values after 24 and 48 h treatments are measured as 2266 and 1956 µg/mL, respectively. Regarding the AFM images and Young`s modulus analysis, SBS significantly induces morphological changes in the cytoplasmic membrane of the treated AGS cells. Expression of survivin, NFƙB, and IL-8 genes is significantly suppressed in AGS cells treated with SBS.

CONCLUSIONS

Considering the antitumor activities of SBS on AGS cell line, it can be regarded as a prospective therapeutic and preventive strategy against human stomach cancer disease.