Probiotic Candidates Research Articles

Safety assessment of probiotic Lactiplantibacillus plantarum MCC5231 and its persistence in gastrointestinal tract

Probiotics are the health beneficial microorganisms and suitable for food industry if found fit for human consumption. In the present study, Lactiplantibacillus plantarum MCC5231, a probiotic bacterium included in vegetable-based beverages, was evaluated for its safety characteristics and gastrointestinal survival using a combined in silico and in vitro approach. The strain was found to be devoid of hemolytic, lecithinase and gelatinase activities. Additionally, it does not consist any transferable antibiotic resistance genes. Further, whole genome sequence analysis revealed the presence of three intact prophages and 14 virulence-associated genes, however, none of them posed a pathogenic threat. Importantly, MCC5231 do not possess any gene associated with toxin production. The strain harbored a CRISPR system, enhancing defense against prophages. Survival assays under simulated gastric and intestinal fluid conditions demonstrated viability rates of 71.4 % and 83.3 %, respectively. Genetic analysis of the mucin binding protein indicated possession of a type II mucin binding domain, suggesting moderate adhesion to intestinal cells. Furthermore, L. plantarum MCC5231 exhibited the ability to produce exopolysaccharides and form biofilms, which may confer additional protection in the gastrointestinal tract. Based on these findings, L. plantarum MCC5231 appears to be a safe probiotic candidate suitable for commercial use in the food industry.

Bacillus paralicheniformis, an acetate-producing probiotic, alleviates ulcerative colitis via protecting the intestinal barrier and regulating the NLRP3 inflammasome

Ulcerative colitis (UC) presents a challenging scenario in digestive health, characterized by recurrent inflammation that is often hard to manage. Bacteria capable of producing short-chain fatty acids (SCFAs) play a pivotal role in mitigating UC symptoms, rendering them promising candidates for probiotic therapy. In this investigation, we assessed the impact of Bacillus paralicheniformis HMPM220325 on dextran sodium sulfate (DSS)-induced UC in mice. Genomic analysis of the strain revealed the presence of protease genes associated with acetate and butyrate synthesis, with acetic acid detected in its fermentation broth. Administration of B. paralicheniformis HMPM220325 to UC mice ameliorated pathological manifestations of the condition and restored intestinal barrier function. Furthermore, B. paralicheniformis HMPM220325 suppressed the activation of the NLRP3 inflammasome signaling pathway and modulated the composition of the intestinal microbiota. These findings shed significant light on the potential of B. paralicheniformis as a probiotic candidate, offering a novel avenue for the prevention and therapeutic intervention of colitis.

Potential probiotic and functional properties of Brettanomyces strains isolated from kombucha tea.

Kombucha, a beverage traditionally obtained through the fermentation of tea, is believed to have beneficial health properties. Therefore, characterizing the microorganisms responsible for this fermentation is essential to demonstrate its potential health benefits and to identify candidates for new probiotics. In this study, four probiotic yeast strains isolated from kombucha tea were identified, by the PCR-RFLP analysis of the ribosomal ITS region and the sequence of the D1/D2 domain of the 26S rDNA, as Brettanomyces bruxellensis (UVI55 and UVI56) and B. anomalus (UVI57 and UVI58). Properties relevant to probiotics were also studied in these strains. All of them showed excellent survival in simulated gastric (99%-100%) and duodenal (95%-100%) juices. The ability to self-aggregate (38%-100%), adhesion to xylene (15%-50%) and, above all, adhesion to Caco-2 cells (4%-21%), revealed its potential capacity to adhere to the intestinal epithelium. In addition, the tested strains showed excellent antioxidant capacity (82%-94%), antimicrobial activity against different pathogens (Escherichia coli, Staphylococcus aureus, Salmonella enterica, Listeria monocytogenes, and Bacillus cereus), as well as remarkable cytotoxic activity against colon, melanoma and ovarian tumor cell lines. Finally, using Caenorhabditis elegans as a model, strain UVI56 exhibited ability to both extend the lifespan of the nematode and protect it against infection by S. enterica. These results support the probiotic and functional properties of the analyzed strains. In conclusion, the study revealed that kombucha tea could be a source of potential probiotics that contribute to its health-promoting properties and that the characterized Brettanomyces strains could be exploited directly as probiotics or for the development of new functional foods.

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

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

Effect of Lactobacillus gasseri BIO6369 and Lacticaseibacillus rhamnosus BIO5326 on Gastric Carcinogenesis Induced by Helicobacter pylori Infection.

Helicobacter pylori infection-associated gastric adenocarcinoma is influenced by various factors, including the digestive microbiota. Lactic acid bacteria role in digestive carcinogenesis has been discussed, and some Lactobacillaceae family species have been shown to act against H. pylori-induced inflammation and colonization. However, their effects on H. pylori-related carcinogenesis have not yet been studied. Lactobacillaceae family effects on the epithelial-to-mesenchymal transition (EMT), emergence of cells with cancer stem cell (CSC) properties and the pro-inflammatory response of gastric epithelial cells to H. pylori infection were investigated. A co-culture model of AGS gastric epithelial cells infected with a carcinogenic strain of H. pylori associated with 18 different probiotic strains candidates were used. Different EMT indicators and CSC properties were studied, including quantification of the mesenchymal phenotype, tumorsphere formation, EMT marker expression, and tight junction evaluation with immunofluorescence microscopy. The effect of the strains on the pro-inflammatory response to H. pylori was also evaluated by quantifying interleukin-8 (IL-8) production using ELISA. Among the strains tested, Lactobacillus gasseri BIO6369 and Lacticaseibacillus rhamnosus BIO5326 induced a 30.6% and 38.4% reduction in the mesenchymal phenotype, respectively, caused a significant decrease in Snail and Zeb1 EMT marker expression and prevented the loss of tight junctions induced by H. pylori infection. A separate co-culture with a Boyden chamber maintained the effects induced by the two strains. H. pylori-induced IL-8 production was also significantly reduced in the presence of L. gasseri BIO6369 and L. rhamnosus BIO5326. Lactobacillus gasseri BIO6369 and L. rhamnosus BIO5326 strains decreased epithelial-to-mesenchymal transition and inflammation induced by H. pylori infection, suggesting that these species may have a protective effect against H. pylori-induced gastric carcinogenesis.

Exploring Weissella confusa W1 and W2 Strains Isolated from Khao-Mahk as Probiotic Candidates: From Phenotypic Traits to Genomic Insights.

Growing interest in probiotics has spurred research into their health benefits for hosts. This study aimed to evaluate the probiotic properties, especially antibacterial activities and the safety of two Weissella confusa strains, W1 and W2, isolated from Khao-Mahk by describing their phenotypes and genotypes through phenotypic assays and whole genome sequencing. In vitro experiments demonstrated that both strains exhibited robust survival under gastric and intestinal conditions, such as in the presence of low pH, bile salt, pepsin, and pancreatin, indicating their favorable gut colonization traits. Additionally, both strains showed auto-aggregation and strong adherence to Caco2 cells, with adhesion rates of 86.86 ± 1.94% for W1 and 94.74 ± 2.29% for W2. These high adherence rates may be attributed to the significant exopolysaccharide (EPS) production observed in both strains. Moreover, they exerted remarkable antimicrobial activities against Stenotrophomonas maltophilia, Salmonella enterica serotype Typhi, Vibrio cholerae, and Acinetobacter baumannii, along with an absence of hemolytic activities and antibiotic resistance, underscoring their safety for probiotic application. Genomic analysis corroborated these findings, revealing genes related to probiotic traits, including EPS clusters, stress responses, adaptive immunity, and antimicrobial activity. Importantly, no transferable antibiotic-resistance genes or virulence genes were detected. This comprehensive characterization supports the candidacy of W1 and W2 as probiotics, offering substantial potential for promoting health and combating bacterial infections.

Probiogenomic analysis of Lactiplantibacillus plantarum SPS109: A potential GABA-producing and cholesterol-lowering probiotic strain

Lactiplantibacillus plantarum SPS109, an isolated strain of lactic acid bacteria (LAB) from fermented foods, showed remarkable potential as a probiotic with dual capabilities in γ-aminobutyric acid (GABA) production and cholesterol reduction. This study employs genomic and comparative analyses to search into the strain's genetic profile, safety features, and probiotic attributes. The safety assessment reveals the absence of virulence factors and antimicrobial resistance genes, while the genome uncovers bacteriocin-related elements, including sactipeptides and a cluster for putative plantaricins, strengthening its ability to combat diverse pathogens. Pangenome analysis revealed unique bacteriocin-related genes, specifically lcnD and bcrA, distinguishing SPS109 from four other L. plantarum strains producing GABA. In addition, genomic study emphasizes SPS109 strain distinctive features, two GABA-related genes responsible for GABA production and a bile tolerance gene (cbh) crucial for cholesterol reduction. Additionally, the analysis highlights several genes of potential probiotic properties, including stress tolerance, vitamin production, and antioxidant activity. In summary, L. plantarum SPS109 emerges as a promising probiotic candidate with versatile applications in the food and beverage industries, supported by its unique genomic features and safety profile.

Development and Evaluation of Bioconverted Milk with Anti-Microbial Effect against Periodontal Pathogens and α-Glucosidase Inhibitory Activity.

To decrease periodontal pathogens and increase the number of beneficial bacteria, probiotics and bioactive compounds made via microbial bioconversion are recently used. In addition, the interest regarding probiotics-mediated bioconversion with popular medicinal plants is increasing. Artemisia herba-alba, a type of wormwood, has recently been attention as a medicinal plant due to its various bioactive compounds. Therefore, we developed bioconverted milk containing A. herba-alba that effectively inhibited periodontal pathogens and α-glucosidase. To select the appropriate lactic acid bacteria for the probiotic candidate strain, 74 strains of lactic acid bacteria were screened. Among them, Lactiplantibacillus plantarum SMFM2016-RK was chosen as the probiotic due to its beneficial characteristics such as high acid and bile tolerance, antioxidant activity, and α-glucosidase inhibition. Based on the minimal bactericidal concentration against three periodontal pathogens, the following appropriate concentrations of Artemisia herba-alba extract were added to milk: 5 mg/mL of A. herba-alba ethanol extract and 25 mg/mL of A. herba-alba hot-water extract. Four bioconverted milks (BM), BM1, BM2, BM3, and BM4, were produced by combining L. plantarum SMFM2016-RK alone, L. plantarum SMFM2016-RK and ethanol extract, L. plantarum SMFM2016-RK and hot-water extract, and L. plantarum SMFM2016-RK with both extracts. As a result of antimicrobial activity, BM3 inhibited the growth of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis the most, and BM4 suppressed the growth of Fusobacterium nucleatum the most. In addition, bioconverted milk containing A. herba-alba (BM2, BM3, and BM4) inhibited α-glucosidase more effectively than BM1. The whole genome of L. plantarum SMFM2016-RK was obtained, and 3135 CDS, 67 tRNA, and 16 RNA were predicted. The genome annotation of L. plantarum SMFM2016-RK revealed 11 CDS related to proteolysis and amino acid metabolism and 2 CDS of phenolic acid-metabolizing enzymes. In conclusion, A. herba-alba-added milk bioconverted by L. plantarum SMFM2016-RK displayed both the growth inhibitory effect on periodontal pathogens and the α-glucosidase inhibitory activity; thus, it necessitates to evaluate the effects on the alleviation of periodontal diseases and glycemic control through future animal experiments.

Probiotics for oral health: a critical evaluation of bacterial strains.

Oral health is critical for total body health and well-being; however, little improvement in oral health status has occurred in the U.S. over the past 20 years. Tooth decay and gum disease remain highly prevalent, with more than 90% and 50% of adults suffering from these conditions, respectively. To combat this lack of improvement, alternative approaches to dental care are now being suggested. One such alternative therapy is probiotics for oral care. In the oral cavity, probiotic strains have been shown to reduce levels of oral pathogens, inhibit the formation of dental caries, and reduce the levels of bacteria that cause halitosis. However, as the oral care probiotic market expands, many products contain bacterial species and strains with no documented health benefits leading to confusion and mistrust among consumers and clinicians. This confusion is enhanced by the regulatory status of probiotic products which puts the onus of safety and efficacy on the manufacturer rather than a central regulatory body. The overarching goal of this review is to provide consumers and clinicians with documented evidence supporting (or refuting) the health benefits of oral care probiotics marketed for sale in the United States. This includes defining what constitutes an oral care probiotic product and a strain level analysis of candidate probiotics from the genera Streptococcus, Lactobacillus, Bifidobacterium, and Bacillus. Additionally, prebiotics and postbiotics will be discussed. Finally, a set of considerations for consumers and clinicians is provided to empower probiotic product decision making. Together, this review will improve understanding of oral care probiotics marketed in the US for dental professionals and consumers.

In vitro investigations on interference of selected probiotic candidates with Campylobacter jejuni adhesion and invasion of primary chicken derived cecal and Caco-2 cells

BackgroundCampylobacter (C.) jejuni is one of the most important bacterial foodborne pathogens worldwide. Probiotics such as Lactobacillus or Bacillus species are considered one option for reducing the colonization rate and magnitude in poultry, the most frequent source of human infections. Due to the lack of suitable avian in vitro models such as chicken intestinal cell lines, especially those derived from the cecum, most in vitro studies on C. jejuni host interaction have been conducted with human intestinal cell lines. In this study, we compared C. jejuni-cell interactions between primary chicken cecal cells and the human intestinal cell line Caco-2, which is derived from colorectal adenocarcinoma, and investigated possible interfering effects of selected probiotic candidates.ResultsWe detected differences in adhesion and invasion between the two tested gut cell types and between different C. jejuni strains. The probiotic inhibition of C. jejuni adhesion and invasion of human and avian gut cells was affected by host cell type, investigated C. jejuni strain and time points of probiotic treatment. Additionally, our results suggest a possible correlation between C. jejuni invasion and the detected increase in IL-6 mRNA expression.ConclusionsOur results indicate distinct differences between avian and human gut cells in their interaction with C. jejuni. Therefore, data obtained in one host species on C. jejuni-host interaction may not easily be transferrable to another one. The factors influencing the variable efficacy of probiotic intervention in chicken and human derived cells should be investigated further.

Re-processing of pharmaceutical herb residues using isolated probiotics from plant sources and their beneficial effects on diarrhea

This study aims to use hot aqueous extract of herbal residue (HRE) to enhance bacterial growth and possess anti-diarrheal effects. In this study, lactobacillus species L. brevis (SAM-1), Lactobacillus plantarum (SAM-2), and Lactobacillus herbinensis (SAM-3) were isolated from date palm sap (collected in winter season). Square Pharmaceuticals PLC, Bangladesh provided herbal residues ‘Adovas’ which is non-sedating herbal cough syrup with sixteen common herbs including Adhatoda vasica. In our observation, HRE increased the number of colonies in MRS media. In the anti-diarrheal study by castor oil and magnesium sulphate-induced diarrheal mouse model, SAM-1 and 2 with or without HRE showed almost similar results. After initial morphological characterization, tests such as resistance to low pH, bile salt and survival capability in gastric simulated fluid (GSF) were performed to confirm them as a probiotic candidate. All three isolates were gram-positive bacteria and could grow in a mesophilic range of temperatures. The isolates were catalase-negative and were able to coagulate milk after overnight incubation. As the isolates exhibited resistance to low pH and could tolerate bile salts, they may survive in the stomach and intestine, thus making them a promising probiotic candidate. The isolated probiotics and HRE inhibited diarrheal and restored the body's electrolytes. Interestingly, SAM-2 showed higher efficacy than the standard drug (Loperamide), while SAM-1 showed a similar effect and SAM-3, had less effect than Loperamide. The findings suggest that probiotics and herbal residue could contribute to diarrhoeal disease prevention, which might be an alternative to a synthetic standard drug (Loperamide).

Exploration and Molecular Identification of Proteolytic Bacteria as Probiotic Candidates from Shrimp Ponds in West Sumatra, Indonesia.

<b>Background and Objective:</b> The existence of intensive shrimp aquaculture faces serious challenges in the form of a decrease in pond water quality due to overfeeding. Efforts are needed to improve pond water quality by utilizing proteolytic bacterial isolates to break down suspended or accumulated feed on the pond bottom. The research aims to find proteolytic bacterial isolates from pond sediments and the digestive tract of shrimp (<i>Litopenaeus vannamei</i>). <b>Materials and Methods:</b> The materials needed are pond sediment samples, shrimp digestive tract, seawater complete agar (SWCA) medium and skim milk agar medium (SMA). The study used survey methods to determine sampling locations and continued with experimental methods in the laboratory. Nine isolates were obtained from pond sediments and two bacterial isolates were from the shrimp digestive tract. <b>Results:</b> The proteolytic potency test showed that two isolates from pond sediments and one isolate from the digestive tract of shrimp were positive for proteolytic. The largest proteolytic index value reached 6.357. Molecular identification by analyzing the <i>16S rRNA</i> gene sequence shows that PC23 isolate is closely related to the bacterium <i>Exiguobacterium indicum </i>strain KR6 with percent identity 99.44-99.58% and PU32 isolate with <i>Bacillus cereus</i> strain 125 with percent identity 100%. <b>Conclusion:</b> The bacteria obtained can be used as probiotic candidates for the future are <i>Exiguobacterium indicum</i> strain KR6 and <i>Bacillus cereus</i> strain 125.

Screening of Probiotic Candidates Bacteria as Biocontrol of Aeromonas Hydrophila Pathogen Isolated from Mina Padi Cultivation Area

The agricultural activities in rice-farming system can have an impact on fish farming and the characteristics of bacterial community, especially pathogenic bacteria. Utilization of probiotics as environmentally friendly biotechnology products can be used to improve environmental quality and suppress the presence of pathogenic bacteria. This study aimed to select bacteria as probiotic agents from aquaculture ponds with the Rice-fish farming system. A total of 22 bacterial isolates were isolated from the water and sediment contained in the culture ponds. Based on the screening results, 15 isolates were confirmed as general non-pathogenic bacteria (Aeromonas sp.), 9 isolates had antibacterial activity against Aeromonas hyrophylla and 4 isolates showed high antibiotic sensitivity and were able to synergize. The results showed the Proteus mirabilis, Proteus penneri, Kurthia gibsonii and Bacillus cereus strains. Bacillus cereus strain LB8 has antibacterial activity that can inhibit the pathogen Aeromonas hydrophila with an inhibition zone of 8mm and has a very high sensitivity to antibiotics. These four isolates are able to work together synergistically and can be used as consortium probiotic bacterial agents to suppress the growth of pathogens.

Bacteria of healthy periodontal tissues as candidates of probiotics: a systematic review

ObjectivesThe use of probiotics could promote the balance of the subgingival microbiota to contribute to periodontal health. This study aimed to identify the potential of bacteria commonly associated with healthy periodontal tissues as probiotic candidates.Material and methodsA systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed, Scopus, Science Direct, ProQuest, and Ovid databases as well as the combination of Medical Subject Headings (MeSH) and non-MeSH terms. Based on the selection criteria, original studies published in English and identifying the microorganisms present in the periodontium of healthy individuals and patients with periodontitis using the high-throughput 16S ribosomal gene sequencing technique were included.ResultsOut of 659 articles, 12 met the criteria for this review. These articles were published from 2012 to 2020 and mainly originated from the United States, China, and Spain. Most of these studies reported adequate criteria for selecting participants, using standardized clinical criteria, and compliance with quality based on the tools used. In periodontal healthy tissue were identified species like Actinomyces viscosus, Actinomyces naeslundii, Haemophilus parainfluenzae, Rothia dentocariosa, Streptococcus sanguinis, Streptococcus mitis, Streptococcus oralis, Streptococcus gordonii, Streptococcus intermedius, and Prevotella nigrescens which have recognized strains with a capacity to inhibit periodontopathogens.ConclusionsS. sanguinis, S. oralis, S. mitis, and S. gordonii are among the bacterial species proposed as potential probiotics because some strains can inhibit periodontopathogens and have been reported as safe for humans.

Whole-genome analysis, evaluation and regulation of in vitro and in vivo GABA production from Levilactobacillus brevis YSJ3

Gamma-aminobutyric acid (GABA) produced by lactic acid bacteria (LAB) is safe and has several health benefits. Levilactobacillus brevis YSJ3 was selected from 110 LAB. It exhibited the highest in vitro GABA production level of 970.10 μg/mL. Whole-genome analysis revealed that L. brevis YSJ3 contained gadR, gadC, gadB and gadA. Furthermore, the Luedeking–Piret model was fitted, which indicated that GABA production was divided into three stages. The gadR 0079, gadC 0080, and gadB 0081 were confirmed to promote GABA synthesis. Moreover, 55 metabolites, particularly those involved in arginine metabolism, were significantly different at 6 and 20 h of cultivation. Notably, L. brevis YSJ3 significantly improved sleep in mice and increased GABA levels in the mice's gut compared with the control group. This suggests that the oral administration of L. brevis YSJ3 improves sleep quality, probably by increasing intestinal GABA levels. Overall, L. brevis YSJ3 was confirmed as a GABA-producing strain in vitro and in vivo, making it a promising probiotic candidate for its application in food and medicine.

Monitoring probiotic properties and safety evaluation of antilisterial Enterococcus faecium strains with cholesterol-lowering potential from raw Cow's milk

Enterococci are an important member of lactic acid bacteria due to their presence in fermented foods, tolerance to low pH and bile salts, bile salt hydrolase (BSH) activity, reducing cholesterol, and producing bacteriocin. However, probiotic and safety issues of enterococci are still debated. It is important to investigate probiotic properties and safety evaluation of these genus because they are intentionally or unintentionally present in foods. In this study, probiotic properties (tolerance to bile salts and simulated gastric juice, antimicrobial and BSH activity, cholesterol lowering potential, auto/co-aggregation, and cell surface hydrophobicity) and safety evaluation (antibiotic resistance, virulence factor, haemolysis and DNase activity, Galleria mellonella infection model, gelatinase activity, and biofilm formation) of Enterococcus faecium (E. faecium) BH04, BH12, BH84, and BH99 isolated raw cow's milk were determined. All strains had high tolerance to bile salts (47.70%–103.84%) and simulated gastric juice (76.80%–82.05%), and antimicrobial activity on L. monocytogenes ATCC 7644 by protein-like substances such as bacteriocin. The strains had strong BSH property and reduced cholesterol by 69.47%–95.00%. The strains were resistant only to gentamicin, kanamycin, and streptomycin and did not have haemolysis and DNase activity. Only gelE and esp genes were detected in some strains. According to the results, it is thought that the E. faecium strains could be possible probiotic candidates. Moreover, this study is the first report on Enterococcus faecium strains isolated from raw cow's milk, which tolerate to bile salt and simulated gastric juice, have BSH potential and antimicrobial activity by protein-like substances, and reduce cholesterol level.

Probiotic Insights from the Genomic Exploration of Lacticaseibacillus paracasei Strains Isolated from Fermented Palm Sap.

This study focused on L. paracasei strains isolated from fermented palm sap in southern Thailand that exhibit potential probiotic characteristics, including antibiotic susceptibility, resistance to gastrointestinal stresses, and antimicrobial activity against various pathogens. However, a thorough investigation of the whole genome sequences of L. paracasei isolates is required to ensure their safety and probiotic properties for human applications. This study aimed to sequence the genome of L. paracasei isolated from fermented palm sap, to assess its safety profile, and to conduct a comprehensive comparative genomic analysis with other Lacticaseibacillus species. The genome sizes of the seven L. paracasei strains ranged from 3,070,747 bp to 3,131,129 bp, with a GC content between 46.11% and 46.17% supporting their classification as nomadic lactobacilli. In addition, the minimal presence of cloud genes and a significant number of core genes suggest a high degree of relatedness among the strains. Meanwhile, phylogenetic analysis of core genes revealed that the strains possessed distinct genes and were grouped into two distinct clades. Genomic analysis revealed key genes associated with probiotic functions, such as those involved in gastrointestinal, oxidative stress resistance, vitamin synthesis, and biofilm disruption. This study is consistent with previous studies that used whole-genome sequencing and bioinformatics to assess the safety and potential benefits of probiotics in various food fermentation processes. Our findings provide valuable insights into the potential use of seven L. paracasei strains isolated from fermented palm sap as probiotic and postbiotic candidates in functional foods and pharmaceuticals.

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

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

Investigation of the marine bacterial community along the coastline of the Gulf of Thailand

The Gulf of Thailand provides many services to the Thai population, and human activities may influence the diversity of microorganisms in the seawater. Information of the microorganisms’ profile which inhabit the coastline can be used to monitor the water quality. This study aimed to investigate the bacterial community in the waters along the coastline provinces, including Rayong, Chonburi, Prachuap Kiri Khan, and Nakhon Sri Thammarat. Seawater samples were collected at each site, and the conductivity, pH, salinity, temperature, and turbidity were measured. The samples were subjected to whole DNA extraction, 16S rRNA amplification, next-generation sequencing, and statistical analysis to identify the bacterial diversity and analyse the effects of water parameters on the bacterial community. The dominant bacterial phyla found were Proteobacteria, Bacteroidota, and Cyanobacteria. Spearman rank correlation analysis revealed a high correlation of Pseudoalteromonas, the NS5 marine group, Lachnospiraceae, Marinobacterium, Mariviven, and Vibrio with the seawater parameters. The predatory bacteria Peredibacter and Halobacteriovorax were reported among these bacterial communities for the first time in the Gulf of Thailand. Interestingly, Akkermansia, a novel candidate for next-generation probiotics to improve human health, was also found in the sample from Nakhon Sri Thammarat Province. Although the rich-ness and diversity of the bacterial communities differed among sampling sites, it is a possible source of many valuable bacteria for future use.

Lactobacillus-derived protoporphyrin IX and SCFAs regulate the fiber size via glucose metabolism in the skeletal muscle of chickens.

The gut microbiota contributes to skeletal muscle energy metabolism and is an indirect factor affecting meat quality. However, the role of specific gut microbes in energy metabolism and fiber size of skeletal muscle in chickens remains largely unknown. In this study, we first performed cecal microbiota transplantation from Chinese indigenous Jingyuan chickens (JY) to Arbor Acres chickens (AA), to determine the effects of microbiota on skeletal muscle fiber and energy metabolism. Then, we used metagenomics, gas chromatography, and metabolomics analysis to identify functional microbes. Finally, we validated the role of these functional microbes in regulating the fiber size via glucose metabolism in the skeletal muscle of chickens through feeding experiments. The results showed that the skeletal muscle characteristics of AA after microbiota transplantation tended to be consistent with that of JY, as the fiber diameter was significantly increased, and glucose metabolism level was significantly enhanced in the pectoralis muscle. L. plantarum, L. ingluviei, L. salivarius, and their mixture could increase the production of the microbial metabolites protoporphyrin IX and short-chain fatty acids, therefore increasing the expression levels of genes related to the oxidative fiber type (MyHC SM and MyHC FRM), mitochondrial function (Tfam and CoxVa), and glucose metabolism (PFK, PK, PDH, IDH, and SDH), thereby increasing the fiber diameter and density. These three Lactobacillus species could be promising probiotics to improve the meat quality of chicken.IMPORTANCEThis study revealed that the L. plantarum, L. ingluviei, and L. salivarius could enhance the production of protoporphyrin IX and short-chain fatty acids in the cecum of chickens, improving glucose metabolism, and finally cause the increase in fiber diameter and density of skeletal muscle. These three microbes could be potential probiotic candidates to regulate glucose metabolism in skeletal muscle to improve the meat quality of chicken in broiler production.