Probiotic and Functional Characterization of Pediococcus acidilactici Isolated from Bhaati jaanr, Traditional Fermented Rice Porridge

Antibiotic Resistance Gene Expression in Veterinary Probiotics: Two Sides of the Coin

The rapid proliferation of antimicrobial resistance has emerged as one of the most pressing animal and public health challenges of our time. Probiotics, extensively employed in human and veterinary medicine, are instrumental in maintaining a balanced microbiome and mitigating its disruption during antibiotic therapy. While their numerous benefits are well documented, probiotics also present potential risks, notably the capacity to harbor antimicrobial resistance genes. This genetic reservoir could contribute to the emergence and spread of antimicrobial resistance by facilitating the horizontal transfer of resistance genes to pathogenic bacteria within the gut. This review critically examines the presence of antimicrobial resistance genes in commonly used probiotic strains, explores the underlying mechanisms of resistance, and provides a balanced analysis of the benefits and risks associated with their use. By addressing these dual aspects, this paper highlights the need for vigilant evaluation of probiotics to preserve their therapeutic potential while minimizing public health risks.

Comprehensive genomics, probiotic, and antibiofilm potential analysis of Streptococcus thermophilus strains isolated from homemade and commercial dahi

This study investigated the probiotic properties and antibiofilm potential of Streptococcus thermophilus strains obtained from homemade and commercial dahi. The S. thermophilus strain from homemade dahi had greater acid tolerance than the commercial strain, indicating a greater capacity to live in the acidic environments of the stomach. The commercial strain had increased survivability in bile salts and was more hydrophobic than the homemade strain. These findings suggest improved adaptability and increased colonization in the gut. The genomes of both strains included genes associated with probiotic characteristics implying that the two strains may provide unique probiotic advantages. These findings highlight the importance of cell-free supernatants (CFS) of these strains in reducing biofilm formation of pathogenic bacteria. Gas chromatography-mass spectrometry demonstrated that 2, 4-di-tert-butylphenol was a shared metabolite in the CFSs of both strains; however, 2-butanol was found only in the CFS of the homemade dahi strain. In-silico investigations revealed that compounds have drug-like characteristics, suggesting that they could be used for treating biofilm-associated diseases. This study highlights the health advantages of probiotics found in traditional dahi, but it also provides a way to develop natural antibacterial medicines.

Safety, Antagonistic Activity, and Probiotic Properties of Lactic Acid Bacteria Isolated from Jeotgal, Korean Fermented Seafoods

Probiotics are in high demand in the health functional food market as they effectively inhibit pathogens and improve host health. Therefore, in order to develop novel probiotic strains, new strains were isolated from various type of jeotgal, traditional Korean fermented seafood products, and their safety and probiotic properties have been evaluated. Based on 16S rRNA gene sequence analysis, six strains (JRD1, Pediococcus pentosaceus; JRD2, Lactiplantibacillus plantarum; JRD6, Pediococcus acidilactici; CLJ21, Lactiplantibacillus plantarum; CLJ24, Pediococcus pentosaceus; CLJ28, Leuconostoc mesenteroides subsp. dextranicum) were selected and subjected to further analysis. As a result, all six strains did not show hemolytic activity, antibiotics resistance, and cell cytotoxicity, confirming that they are safe for human use. Among them, JRD1, JRD6, and CLJ24 exhibited high survival rates under simulated gastrointestinal conditions. Additionally, these three strains demonstrated strong adhesion abilities on HT-29 cells, with values of 6.02, 5.77, and 5.86 log CFU/mL, respectively. Furthermore, JRD1, JRD6, and CLJ24 showed relatively high antagonistic activity against both Salmonella Typhimurium and Staphylococcus aureus through competition, exclusion, and displacement of their adhesion. Interestingly, cell-free supernatants (CFS) from three strains effectively inhibited the growth of both S. Typhimurium and S. aureus. Furthermore, CFS of CLJ24, JRD1, and JRD6 demonstrated anti-inflammatory effects in intestinal epithelial cells. The results suggest that CLJ24, JRD1, and JRD6 have potential to be development as functional probiotic strains with both antibacterial and anti-inflammatory activities.

Application of Lactobacillus plantarum and Pediococcus lactis on Lipid Metabolism, Anti-Inflammatory, and Fecal Microbiota in Cats

Probiotics have been used in functional foods and dietary supplements, and in recent years, they have become more widely used in pets. In our previous experiment, Lactobacillus plantarum L-27-2 and Pediococcus lactis L-14-1 were isolated from cat feces and proved to have positive effects on lipid metabolism in mice. To further discuss their possible effects in cats, a total of 12 healthy cats (British Shorthair) were randomly divided into two groups. One group was fed Pediococcus lactis L-14-1 (1 × 109 CFU/kg/d, n = 6), and the other group was fed Lactobacillus plantarum L-27-2 (1 × 109 CFU/kg/d, n = 6), and the experiment was conducted for 28 days. Blood and feces were collected on days 0 and 28 separately. ELISA was used to detect blood biochemical indexes in cats. The results showed that L-27-2 and L-14-1 could reduce the content of TG (triglyceride, p < 0.05) and LDL-C (low-density lipoprotein cholesterol, p < 0.01) in the blood, increase the content of HDL-C (high-density lipoprotein, p < 0.01), and L-27-2 could significantly reduce the content of IL-6 (p < 0.01). The diversity of feces microbiota was also tested. On the phylum level, there was no significance in the phylum level of Firmicutes and Bacteroidetes (p > 0.05), but on the genus level, in the L-14-1 group, the abundance of Lantiplantibacillus and Cetobacterium was increased (p < 0.05), and the abundance of Ruminococcus, Olsenella, and Labanicoccus was decreased (p < 0.05), while in the L-27-2 group, the abundance of Libanicoccus was also decreased in L-14-1 (p < 0.05). Above all, L-27-2 and L-14-1 can be considered potential probiotics to improve cat gut health and lipid metabolism.

Metagenomic insights into traditional fermentation of rice-based beverages among ethnic tribes in southern Assam, Northeast India

Introduction

Traditional fermented foods have long been recognized for their numerous health benefits along with their potential to aid in the treatment of gastrointestinal disorders. These fermented foods have been shown to promote gut health and contribute to a longer, healthier life.

Methods

The high-throughput sequencing using the Illumina MiSeq platform was employed to investigate the microbiome communities of rice-based fermented beverages consumed by ethnic tribes in Southern Assam, namely Zeme Naga, Dimasa Kachari, Hmar, Karbi and Tea tribes.

Results

The fermented rice-based beverages were highly predominated by Firmicutes, Bacteroides, Proteobacteria, and Actinobacteria exhibiting the highest relative abundance across all tribes. At genus level, significant abundance of pediococcus, lactobacillus, bacillus, leuconostoc, acetobacter, staphylococcus, delftia, erwinia, klebsiella and chrysebacterium were found amongst these ethnic tribes.

Discussion

Understanding the fermented food microbiome will help to know the relationships between microbial communities and their effect on health of humans amongst the tribes. Furthermore, the use of these fermented products could provide enhanced health benefits to southern Assam region of India.

Exploring diversity and functional traits of lactic acid bacteria in traditional vinegar fermentation: A review

Vinegar has been used for centuries as a food preservative, flavor enhancer, and medicinal agent. While commonly known for its sour taste and acidic properties due to acetic acid bacteria metabolism, vinegar is also home to a diverse community of lactic acid bacteria (LAB). The main genera found during natural fermentation include Lactobacillus, Lacticaseibacillus, Lentilactobacillus, Limosilactbacillus, Leuconostoc, and Pedicoccus. Many of the reported LAB species fulfill the probiotic criteria set by the World Health Organization (WHO). However, it is crucial to acknowledge that LAB viability undergoes a significant reduction during vinegar fermentation. While containing LAB, none of the analyzed vinegar met the minimum viable amount required for probiotic labeling. To fully unlock the potential of vinegar as a probiotic, investigations should be focused on enhancing LAB viability during vinegar fermentation, identifying strains with probiotic properties, and establishing appropriate dosage and consumption guidelines to ensure functional benefits. Currently, vinegar exhibits substantial potential as a postbiotic product, attributed to the high incidence and growth of LAB in the initial stages of the fermentation process. This review aims to identify critical gaps and address the essential requirements for establishing vinegar as a viable probiotic product. It comprehensively examines various relevant aspects, including vinegar processing, total and LAB diversity, LAB metabolism, the potential health benefits linked to vinegar consumption, and the identification of potential probiotic species.

Investigating the antidiabetic efficacy of dairy-derived Lacticaseibacillus paracasei probiotic strains: modulating α-amylase and α-glucosidase enzyme functions

The current study aims to evaluate and characterize the probiotic andantidiabetic properties of lactic acid bacteria (LAB) obtained from milk and other dairy-based products. The strains were tested physiologically, biochemically, and molecularly. Based on biochemical tests and 16S rRNA gene amplification and sequencing, all three isolates RAMULAB18, RAMULAB19, and RAMULAB53 were identified as Lacticaseibacillus paracasei with homology similarity of more than 98%. The inhibitory potential of each isolate against carbohydrate hydrolysis enzymes (α-amylase and α-glucosidase) was assessed using three different preparations of RAMULAB (RL) isolates: the supernatant (RL-CS), intact cells (RL-IC), and cell-free extraction (RL-CE). Additionally, the isolate was evaluated for its antioxidant activity against free radicals (DPPH and ABTS). The strain's RL-CS, RL-CE, and RL-IC inhibited α-amylase (17.25 to 55.42%), α-glucosidase (15.08-59.55%), DPPH (56.42-87.45%), and ABTS (46.35-78.45%) enzymes differently. With the highest survival rate (>98%) toward tolerance to gastrointestinal conditions, hydrophobicity (>42.18%), aggregation (>74.21%), as well as attachment to an individual's colorectal cancer cell line (HT-29) (>64.98%), human buccal and chicken crop epithelial cells, all three isolates exhibited extensive results. All three isolates exhibited high resistance toward antibiotics (methicillin, kanamycin, cefixime, and vancomycin), and other assays such as antibacterial, DNase, hemolytic, and gelatinase were performed for safety assessment. Results suggest that the LAB described are valuable candidates for their significant health benefits and that they can also be utilized as a beginning or bio-preservative tradition in the food, agriculture, and pharmaceutical sectors. The LAB isolates are excellent in vitro probiotic applicants and yet additional in vivo testing is required.

Gut microbiota-derived short-chain fatty acids regulate gastrointestinal tumor immunity: a novel therapeutic strategy?

Tumor immune microenvironment (TIME), a tumor-derived immune component, is proven to be closely related to the development, metastasis, and recurrence of tumors. Gut microbiota and its fermented-metabolites short-chain fatty acids (SCFAs) play a critical role in maintaining the immune homeostasis of gastrointestinal tumors. Consisting mainly of acetate, propionate, and butyrate, SCFAs can interact with G protein-coupled receptors 43 of T helper 1 cell or restrain histone deacetylases (HDACs) of cytotoxic T lymphocytes to exert immunotherapy effects. Studies have shed light on SCFAs can mediate the differentiation and function of regulatory T cells, as well as cytokine production in TIME. Additionally, SCFAs can alter epigenetic modification of CD8⁺ T cells by inhibiting HDACs to participate in the immune response process. In gastrointestinal tumors, the abundance of SCFAs and their producing bacteria is significantly reduced. Direct supplementation of dietary fiber and probiotics, or fecal microbiota transplantation to change the structure of gut microbiota can both increase the level of SCFAs and inhibit tumor development. The mechanism by which SCFAs modulate the progression of gastrointestinal tumors has been elucidated in this review, aiming to provide prospects for the development of novel immunotherapeutic strategies.