Antibacterial activity Lactobacillus plantarum isolated from fermented vegetables and investigation of the plantaricin genes

Unraveling the antimicrobial potential of Lactiplantibacillus plantarum strains TE0907 and TE1809 sourced from Bufo gargarizans: advancing the frontier of probiotic-based therapeutics

Introduction

In an era increasingly defined by the challenge of antibiotic resistance, this study offers groundbreaking insights into the antibacterial properties of two distinct Lactiplantibacillus plantarum strains, TE0907 and TE1809, hailing from the unique ecosystem of Bufo gargarizans. It uniquely focuses on elucidating the intricate components and mechanisms that empower these strains with their notable antibacterial capabilities.

Methods

The research employs a multi-omics approach, including agar diffusion tests to assess antibacterial efficacy and adhesion assays with HT-29 cells to understand the preliminary mechanisms. Additionally, gas chromatography-mass spectrometry (GC-MS) is employed to analyze the production of organic acids, notably acetic acid, and whole-genome sequencing is utilized to identify genes linked to the biosynthesis of antibiotics and bacteriocin-coding domains.

Results

The comparative analysis highlighted the exceptional antibacterial efficacy of strains TE0907 and TE1809, with mean inhibitory zones measured at 14.97 and 15.98 mm, respectively. A pivotal discovery was the significant synthesis of acetic acid in both strains, demonstrated by a robust correlation coefficient (cor ≥ 0.943), linking its abundance to their antimicrobial efficiency. Genomic exploration uncovered a diverse range of elements involved in the biosynthesis of antibiotics similar to tetracycline and vancomycin and potential regions encoding bacteriocins, including Enterolysin and Plantaricin.

Conclusion

This research illuminates the remarkable antibacterial efficacy and mechanisms intrinsic to L. plantarum strains TE0907 and TE1809, sourced from B. gargarizans. The findings underscore the strains' extensive biochemical and enzymatic armamentarium, offering valuable insights into their role in antagonizing enteric pathogens. These results lay down a comprehensive analytical foundation for the potential clinical deployment of these strains in safeguarding animal gut health, thereby enriching our understanding of the role of probiotic bacteria in the realm of antimicrobial interventions.

One Health Probiotics as Biocontrol Agents: One Health Tomato Probiotics

Tomato (Lycopersicon esculentum) is one of the most popular and valuable vegetables in the world. The most common products of its industrial processing in the food industry are juice, tomato paste, various sauces, canned or sun-dried fruits and powdered products. Tomato fruits are susceptible to bacterial diseases, and bacterial contamination can be a risk factor for the safety of processed tomato products. Developments in bioinformatics allow researchers to discuss target probiotic strains from an existing large number of probiotic strains for any link in the soil-plant-animal-human chain. Based on the literature and knowledge on the "One Health" concept, this study relates to the suggestion of a new term for probiotics: "One Health probiotics", beneficial for the unity of people, animals, and the environment. Strains of Lactiplantibacillus plantarum, having an ability to ferment a broad spectrum of plant carbohydrates, probiotic effects in human, and animal health, as well as being found in dairy products, vegetables, sauerkraut, pickles, some cheeses, fermented sausages, fish products, and rhizospheric soil, might be suggested as one of the probable candidates for "One Health" probiotics (also, for "One Health-tomato" probiotics) for the utilization in agriculture, food processing, and healthcare.

Probiotic Potentiality from Versatile Lactiplantibacillus plantarum Strains as Resource to Enhance Freshwater Fish Health

Dietary probiotic supplementation has the potential to enhance the health of fish and their disease resistance. In this study, some properties of ten Lactiplantibacillus plantarum strains have been evaluated, for their potential use as probiotics in freshwater fish diet. In particular, antimicrobial activity, antioxidant activity, the potentiality to survive the gastrointestinal transit and persist in the intestine, were evaluated in vitro. The experimental tests were carried out at 15 °C and 30 °C to determine the suitability of these lactic acid bacteria to be used as probiotics in the diet of fish grown at different temperatures. The results demonstrated that the evaluated Lp. plantarum strains, which often have significant differences among themselves, are characterized by important functional characteristics such as cell surface properties (auto-aggregation and hydrophobicity), ability to produce antioxidant substances, capacity to survive in the presence of 0.3% bile salts and acidic environment (2.5 pH), antagonistic activity against some fish opportunistic pathogens (A. salmonicida, Ps. aeruginosa, E. coli and C. freundii) and other unwanted bacteria present in fish products (S. aureus and L. innocua). The outcomes suggest that these Lp. plantarum strains may be candidates as probiotics in warm- and cold-water aquaculture.

Rhizospheric Lactobacillus plantarum (Lactiplantibacillus plantarum) strains exhibit bile salt hydrolysis, hypocholestrolemic and probiotic capabilities in vitro

Lactobacillus plantarum (renamed as Lactiplantibacillus plantarum) has been isolated from many sources but very rarely from rhizospheric soil. This is the first report on isolation and assessment of probiotic capabilities of L. plantarum strains isolated from rhizospheric soil. The isolates were confirmed by 16S rRNA gene sequencing and named as NS14, NS16 and NGG. All the isolates were evaluated for bile salt hydrolysis, hypocholestrolemic potential and probiotic attributes. Our results indicated that all the strains harboured bsh and showed in vitro cholesterol assimilation capabilities which increased when bile salts were also present in the culture medium. Also, all the strains remained viable at high temperatures and in the presence of NaCl, lysozyme, simulated gastric juice, bile salts and, exhibited auto- and co-aggregation capabilities. Additionally, L. plantarum strain NS14 survived in the presence of phenols, acidic environment (pH 2-3) and was resistant to many clinically relevant antibiotics. Since, L. plantarum NS14 exhibited most of the desirable and essential characteristics of a probiotic it should be further investigated as a potent probiotic with an additional benefit as a hypocholesterolemic biotherapeutic. Moreover, rhizosphere can be explored as a useful ecological niche for isolating microorganisms with biotechnological and probiotic potential.

Rhizospheric Lactobacillus plantarum (Lactiplantibacillus plantarum) strains exhibit bile salt hydrolysis, hypocholestrolemic and probiotic capabilities in vitro

Lactobacillus plantarum (renamed as Lactiplantibacillus plantarum) has been isolated from many sources but very rarely from rhizospheric soil. This is the first report on isolation and assessment of probiotic capabilities of L. plantarum strains isolated from rhizospheric soil. The isolates were confirmed by 16S rRNA gene sequencing and named as NS14, NS16 and NGG. All the isolates were evaluated for bile salt hydrolysis, hypocholestrolemic potential and probiotic attributes. Our results indicated that all the strains harboured bsh and showed in vitro cholesterol assimilation capabilities which increased when bile salts were also present in the culture medium. Also, all the strains remained viable at high temperatures and in the presence of NaCl, lysozyme, simulated gastric juice, bile salts and, exhibited auto- and co-aggregation capabilities. Additionally, L. plantarum strain NS14 survived in the presence of phenols, acidic environment (pH 2–3) and was resistant to many clinically relevant antibiotics. Since, L. plantarum NS14 exhibited most of the desirable and essential characteristics of a probiotic it should be further investigated as a potent probiotic with an additional benefit as a hypocholesterolemic biotherapeutic. Moreover, rhizosphere can be explored as a useful ecological niche for isolating microorganisms with biotechnological and probiotic potential.

Design and preparation of antimicrobial meat wrapping nanopaper with bacterial cellulose and postbiotics of lactic acid bacteria

Lyophilized postbiotics of Lactobacillus plantarum was prepared and impregnated in bacterial nanocellulose (BNC) by ex-situ method to develop an antimicrobial ground meat wrapping nanopaper. The postbiotics incorporated BNC (P-BNC) films were optimized by response surface methodology and their antimicrobial activity against Listeria monocytogenes were examined. The BNC with postbiotics at 21.21% concentration and 28 min impregnation time was chosen as an optimized P-BNC film. The FTIR results confirmed the immobilization of postbiotics in BNC. The P-BNC film represented a significant reduction (~5 log cycles) in L.monocytogenes counts in ground meat at the end of the storage period (9 days at 4 °C). Meat wrapped by P-BNC film displayed a significant decrease in total mesophilic and psychrophiles count and TBA values than the controls. BNC can be considered as a proper carrier for development of antimicrobial film using postbiotics of LAB for food application.