Screening Of Probiotics Research Articles

Screening and Characterization of Probiotics Isolated from Traditional Fermented Products of Ethnic-Minorities in Northwest China and Evaluation Replacing Antibiotics Breeding Effect in Broiler.

In this study, Lactobacillus fermentum DM7-6 (DM7-6), Lactobacillus plantarum DM9-7 (DM9-7), and Bacillus subtilis YF9-4 (YF9-4) were isolated from traditional fermented products. The survival rate of DM7-6, DM9-7, and YF9-4 in simulated intestinal gastric fluid reached 61.29%, 44.82%, and 55.26%, respectively. These strains had inhibition ability against common pathogens, and the inhibition zone diameters were more than 7 mm. Antioxidant tests showed these strains had good scavenging capacity for superoxide anion, hydroxyl radical and DPPH, and the total reduction capacity reached 65%. Then DM7-6, DM9-7 and YF9-4 were fed to broilers to study the effects on antioxidant capacity, immune response, biochemical indices, tissue morphology, and gut microbiota. 180 healthy broilers were allocated randomly into six experimental groups. SOD, GSH-Px, and T-AOC in broilers serum were detected, and the results showed probiotics significantly improve antioxidant capacity compared to CK group, while antibiotics showed the opposite result. Besides, IgA, IgM, IgG, TNF-α, and IL-2 indicated it could significantly improve immunity by adding probiotics in broilers diets. However, antibiotics reduced immunoglobulin levels and enhanced inflammation index. Biochemical indicators and tissue morphology showed probiotics had a protective effect on metabolic organs. Gut microbiota analysis proved antibiotics could significantly decrease microbial community diversity and increase the proportion of opportunistic pathogens, while probiotics could improve the diversity of gut microbiota and promote the colonization of beneficial microorganisms. In summary, probiotics DM7-6, DM9-7, and YF9-4 can improve the broiler's health by improving antioxidant capacity and immune function, regulating gut microbiota, and can be used as alternative probiotics for antibiotics-free breeding of broilers.

Screening and effects of intestinal probiotics on growth performance, gut health, immunity, and disease resistance of Nile tilapia (Oreochromis niloticus) against Streptococcus agalactiae

In the present study, 59 autochthonous bacteria were isolated from the intestine of tilapia. Following enzyme producing activity, antagonistic ability, hemolytic activity, drug sensitivity assessments, and in vivo safety evaluation, 7 potential probiotic strains were screened out: Bacillus tequilensis BT0825-2 (BT), Bacillus aryabhattai BA0829-3 (BA1), Bacillus megaterium BM0505-6 (BM), Bacillus velezensis BV0505-11 (BV), Bacillus licheniformis BL0505-18 (BL), B. aryabhattai BA0505-19 (BA2), and Lactococcus lactis LL0306-15 (LL). Subsequently, tilapia were fed basal diets (CT) and basal diets supplemented with 108 CFU/g of BT, BA1, BM, BV, BL, BA2 and LL, respectively. After 56 days of continuous feeding, the growth parameters (weight gain, final weight, and specific growth rate) showed significant improvement (p < 0.05) in both BM and BA2 groups. The total cholesterol and triglycerides of serum were significantly decreased in BV and LL groups (p < 0.05). The superoxide dismutase, glutathione reductase, and lysozyme of BV, BA2 and LL groups were increased, and the malondialdehyde of BV group was significantly decreased. The villous height and amylase of midgut were increased in BV, BA2 and LL groups. In addition, the expression levels of ZO-1 and occludin genes in the midgut of tilapia were enhanced in BM, BV, BA2 and LL groups. The supplementation of probiotics reduced the abundance of Cyanobacteria and increased the abundance of Actinobacteria at the phylum level. At the genus level, the addition of probiotics increased the abundance of Romboutsia. Furthermore, improvement in the expression of immune-related genes were observed, including interleukin 1β, interleukin 10, tumor necrosis factor alpha, and transforming growth factor beta (p < 0.05). After challenging with S. agalactiae, the survival rates of BV, BA2 and LL groups were significantly higher than CT group (p < 0.05). Above results indicated that BM, BA2, BV and LL improved growth performance, gut health or immunity of tilapia, which can be applied in tilapia aquaculture.

Novel method for screening probiotic candidates tolerant to human gastrointestinal stress

Tolerance to human gastrointestinal stressors is crucial for probiotics to exhibit their health benefits; however, there is no standardised method for screening their stress tolerance. In this study, we proposed a novel method for screening probiotic candidates tolerant to human gastrointestinal stress—gastrointestinal tolerance assay and culture (GTA-C) method—using black polyethylene terephthalate (PET) non-woven fabric as a scaffold to modify the specialized cellulose film (SCF) method. The modified SCF method showed excellent pH-based diffusion of medium components, had minimal effect on the growth of Escherichia coli K12, and improved the visibility of the colonies. Analysis of kimchi samples cultured using the SCF and modified SCF methods revealed that the modified method diversified the cultured bacteria. GTA in a simulated human fasting state using the modified SCF method showed that acid stress significantly affected the growth of four bacteria used as probiotics and that tolerance to acid stress may be species-dependent. Screening of probiotics in kimchi samples resulted in the identification of lactic acid bacteria tolerant to human gastrointestinal stress during fasting. Our results indicate that the modified SCF method (GTA-C method) is useful for screening probiotics resistant to the gastrointestinal environment during fasting.

Screening and identification of probiotics from the intestinal tract of largemouth bass (Micropterus salmoides) for use as a feed additive and bacterial infection control

Probiotics regulate the health of the host by influencing digestion and absorption, intestinal morphology, microbial composition, and the host's defense against infection. The genus Bacillus encompasses several known probiotics capable of surviving harsh feed processing and extended storage conditions. More importantly, these microbes can still confer probiotic benefits even when administered to animals in the form of spores. Therefore, the screening of Bacillus strains with probiotic potential holds significant importance for aquaculture. In our study, we screened a total of 75 Bacillus strains, leading to the identification of a promising candidate strain, Bacillus velezensis (BSG-2), which has the excellent performance of antagonism towards pathogenic bacteria including Aeromonas hydrophila, Edwardsiella piscicida, and Nocardia seriolae. Genome sequencing provided the evidence of the antibacterial-related genes and gene clusters associated with secondary metabolism. In addition, BSG-2 has a prominent ability to endure harsh environment and secret digestive enzymes, which indicated that BSG-2 has the potential to survive and promote digestion in the intestinal tract through the gastrointestinal tract. Importantly, feeding 56 days, BSG-2 increased activities of digestive and immune-related enzymes, and then promoted growth and decreased mortality and tissue damage of largemouth bass after Nocardia seriolae infection. Collectively, our findings demonstrate that Bacillus velezensis BSG-2 is a promising probiotic candidate offering multiple benefits for largemouth bass.

Analysis of gut microbiota of ladybug beetle (Harmonia axyridis) after feeding on different artificial diets

BackgroundHarmonia axyridis is an effective natural enemy insect to a variety of phloem-sucking pests and Lepidopteran larvae, such as aphids, scabies, and phylloxera, while its industrial production is limited due to unmature artificial diet. Insect intestinal microbiota affect host development and reproduction. The aim of this study is to understand intestinal microbiota composition of H. axyridis and screen effective probiotics on artificial diet. Considering the role of the components and composition of the diet on the structure and composition of the intestinal microbiome, four kinds of diets were set up: (1) aphid; (2) basic diet; (3) basic diet + glucose; (4) basic diet + trehalose. The gut microbiota of H. axyridis was detected after feeding on different diets.ResultsResults showed that the gut microbiota between artificial diet group and aphid groups were far apart, while the basic and glucose groups were clearly clustered. Besides, the glucose group and trehalose group had one unique phylum, Cryptophyta and Candidatus Saccharibacteria, respectively. The highest abundance of Proteobacteria was found in the aphid diet. The highest abundance of Firmicutes was found in the basic diet. However, the addition of glucose or trehalose alleviated the change. In addition, the relative abundance of Enterobacter, Klebsiella, Enterobacteriaceae_unclassified, Enterobacteriales_unclassified and Serratia in the aphid group was higher than other groups. Moreover, the function of gut genes in each group also showed clear differences.ConclusionThese results have offered a strong link between artificial diets and gut microbes, and also have provided a theoretical basis for the screening of synergistic probiotics in artificial diet.

Screening of oxalate-degrading probiotics and preventive effect of Lactiplantibacillus plantarum AR1089 on kidney stones.

Calcium oxalate stone is the main type of kidney stone, so far there is no specific drug treatment. Here, we screened for oxalate-degrading probiotics and evaluated the potential preventive effect of lactic acid bacteria in rats with hyperoxaluria-induced kidney stones. The oxalate degradation efficiencies of the probiotics were determined to be 5-20% by in vitro experiments, of which the degradation efficiencies of Lactiplantibacillus plantarum AR342 and L. plantarum AR1089 were 17.32% and 14.15%, respectively. Through animal experiments, we found that L. plantarum AR1089 significantly attenuated kidney injury, as demonstrated by improving renal dysfunction and renal fibrosis, lowering creatinine and urea nitrogen levels. L. plantarum AR1089 was also effective in decreasing the number of calcium oxalate crystals in the urine and kidneys as well as ameliorating oxidative stress as evidenced by lowering the level of MDA and decreasing the level of SOD and CAT. Moreover, supplementation of L. plantarum AR1089 inhibited renal crystalline deposition by down-regulating the expression of KIM-1, OPN and MCP-1, and prevented hyperoxaluria-induced kidney stones by regulating the gut microbiota. Taken together, the present study shows that oral administration of L. plantarum AR1089, by attenuating kidney injury and regulating gut microbiota, is a potential therapy to reduce calcium oxalate crystals and prevent the progression of kidney stones.

Screening of anti-allergic Lactiplantibacillus species by splenocyte sensitization model and evaluate their probiotic and postbiotic characteristics

Lactiplantibacillus species has garnered considerable attention due to its multifaceted probiotic properties, particularly its potential in alleviating food allergies. Despite numerous reports supporting this claim, scant research exists concerning the methodology for screening anti-allergic probiotics. Thus study sought to establish an in vitro splenocyte sensitization model for the purpose of screening potential anti-allergic Lactiplantibacillus strains. Through the splenocyte model, different Lactiplantibacillus strains were assessed for their ability to modulate the Th1/Th2 balance in sensitized splenocytes. The results showed that compared with the of positive control (IFN-γ/IL-4 value was 1.12) and LGG (IFN-γ/IL-4 value was 15.88), Lactiplantibacillus XJ 002, TLF 1-2 and TLF 5-3-2 had the greatest effect on improving IFN-γ/IL-4 value, which were 9.89, 15.81 and 9.72 respectively. The further results showed that the IL-10 levels of Lactiplantibacillus XJ 002, TLF 1-2 and TLF 5-3-2 reached 125.23, 147.44 and 113.16 ng/L, which were significantly higher than the positive control (84.95 ng/L, p < 0.05). Moreover, the IgE reduction rates of Lactiplantibacillus XJ 002, TLF 1-2 and TLF 5-3-2 were 82%, 72% and 40% respectively, which indicated that Lactiplantibacillus XJ 002 and TLF 1-2 showed the best regulatory ability. Subsequently, Lactiplantibacillus XJ 002 and TLF 1-2 were considered promising probiotic candidates following rigorous probiotic evaluation. Remarkably, the inactivated forms of these strains, functioning as postbiotics, exhibited similar anti-allergic effects to those of the live bacteria. Consequently, this study not only offers valuable insights into the screening of anti-allergic probiotics but also explores the potential applications of postbiotics.

Gut Microbial Diversity Analysis of Different Native Chickens and Screening of Chicken-Derived Probiotics

The gut microbiota plays a critical role in the growth, development, nutritional digestion, and overall health of chickens. Furthermore, certain probiotics isolated from poultry intestines have demonstrated the potential to enhance immune function and production performance in chickens. To investigate the differences in gut microbiota among chickens from various geographical environments and different breeds of broiler and laying hens, we conducted 16S rRNA sequencing on the fecal microbiota of 140 Chinese native chickens and ten Roman layers. In addition, we isolated and screened the potential probiotics to examine their biological characteristics, genome profiles, and functionality in animals. Our findings revealed the significant variations in gut microbiota composition and structure between Tibetan chickens (ZJ), which reside in high-altitude regions, and Meihua chickens (MH) and Xuhai chickens (XH), which inhabit low-altitude regions. Specifically, Cupriavidus and Candidatus_Bacilloplasma were identified as unique microbial communities in high and low altitudes, respectively. Notably, among regions with similar altitudes, Luning chickens (LN) exhibited the lowest α diversity, accompanied by a remarkably high relative abundance of Firmicutes and Lactobacillus. Conversely, Wugu chickens (WGs) and Yaoshan chickens (YSs) displayed similar gut microbiota profiles. Furthermore, distinctive gut microbiota patterns were observed between the different breeds of broilers and laying hens. Commercial Roman layers (LMs) exhibited significantly lower alpha diversity compared to native chickens, and broilers and laying hens predominantly harbored Firmicutes, Bacteroidota, and Proteobacteria. Of particular interest, the probiotics Lactobacillus agilis MH1 and Lactobacillus salivarius ZJ1, derived from chicken feces, exhibited favorable genomic profiles, and demonstrated anti-colitis effects and immunomodulatory functions. These findings provide a crucial theoretical foundation for native chicken research and offer insights for the future development and formulation of chicken-derived probiotics.

Multi-function screening of probiotics to improve oral health and evaluating their efficacy in a rat periodontitis model.

The oral cavity is the second most microbially rich region of the human body, and many studies have shown that there is a strong association between microorganisms and oral health. Some pathogenic bacteria produce biofilms and harmful metabolites in the mouth that may cause oral problems such as oral malodor, periodontitis, and dental caries. Altering the oral microbiota by using probiotics may alleviate oral health problems. Thus, using multi-function screening, we aimed to identify probiotics that can significantly improve oral health. The main parameters were the inhibition of pathogenic bacteria growth, inhibition of biofilm formation, reduction in the production of indole, H2S, and NH3 metabolites that cause halitosis, increase in the production of H2O2 to combat harmful bacteria, and co-aggregation with pathogens to prevent their adhesion and colonization in the oral cavity. Tolerance to cholic acid and choline was also assessed. Bifidobacterium animalis ZK-77, Lactobacillus salivarius ZK-88, and Streptococcus salivarius ZK-102 had antibacterial activity and inhibited biofilm production to prevent caries. They also improved the oral malodor parameter, H2S, NH3, and indole production. The selected probiotics (especially L. salivarius ZK-88) alleviated the inflammation in the oral cavity of rats with periodontitis. The analysis of the gingival crevicular fluid microbiome after probiotic intervention showed that B. animalis ZK-77 likely helped to restore the oral microbiota and maintain the oral microecology. Next, we determined the best prebiotics for each candidate probiotic in order to obtain a formulation with improved effects. We then verified that a probiotics/prebiotic combination (B. animalis ZK-77, L. salivarius ZK-88, and fructooligosaccharides) significantly improved halitosis and teeth color in cats. Using whole-genome sequencing and acute toxicity mouse experiments involving the two probiotics, we found that neither probiotic had virulence genes and they had no significant effects on the growth or development of mice, indicating their safety. Taking the results together, B. animalis ZK-77 and L. salivarius ZK-88 can improve oral health, as verified by in vivo and in vitro experiments. This study provides a reference for clinical research and also provides new evidence for the oral health benefits of probiotics.

Phenotypic screening of novel probiotics with potential anti-neuroinflammation activity based on cell and zebrafish models

Neuroinflammation, a major pathological factor contributing to various neurodegenerative diseases, is closely associated with gut microbiota imbalance. The aim of this study was to establish a rapid and efficient screening method to obtain potential anti-neuroinflammatory strains. Firstly, 94 strains isolated from different sources were screened against neuroinflammation in lipopolysaccharide (LPS)-activated BV-2 cells model to identify potential strains quickly. In vitro cellular experiments revealed that 21 strains significantly inhibited nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) activity, which were selected for further evaluation of gastrointestinal tolerance and adhesion properties. Among them, 18 strains with promising probiotic properties were further confirmed for anti-neuroinflammatory effects in vivo using the CuSO4-induced zebrafish model. The results showed that eight strains significantly mitigated the migratory behavior of zebrafish neutrophils and the mRNA expression level of pro-inflammatory cytokines IL-1β compared to other strains. Additionally, Lactiplantibacillus plantarum and Limosilactobacillus fermentum were identified as the main species by sequencing their 16S rDNA. In conclusion, this cell-zebrafish model is promising for high-throughput screening of novel probiotics with potential anti-neuroinflammation activity.

Combination of Lycium barbarum L. and Laminaria japonica polysaccharides as a highly efficient prebiotic: Optimal screening and complementary regulation of gut probiotics and their metabolites

The combination of polysaccharides is an effective way to develop prebiotics with stable performance during processing and digestion for human wellness. However, there is little information on optimal screening and complementary regulation of compound polysaccharides. This study aimed to optimally select a combination of Lycium barbarum L. polysaccharide (LBP) and Laminaria japonica polysaccharide (LJP) as a highly efficient prebiotic to regulate the gut probiotics and their metabolites. Two LBPs characterized as rhamnogalacturonan I enriched pectins and two LJPs characterized as fucoidans were obtained by enzyme-assisted acid extraction at moderate and dramatic temperatures and combined in pairs to obtain 4 groups containing 4 proportional combinations. All combinations showed better prebiotic effects than individual LJP. The combination of LBP and LJP extracted at 50 °C at a ratio of 4:1 exhibited the strongest prebiotic effect. The optimal compound polysaccharide achieved superior effect and complementary function via LBP-targeted proliferation of Bifidobacterium, Lactobacillus, and Bacteroides and production of SCFAs and non-SCFA health-associated metabolites, LJP-targeted accumulation of butyrate-producing bacteria and corresponding metabolites, as well as synergistic effect of LJP and LBP at exact proportion. Our study provided theoretical and methodological guidance for optimal screening of compound polysaccharides as new prebiotics.

A Screening Model for Probiotics Against Specific Metabolic Diseases Based on Caco-2 Monolayer Membrane

Recent studies have revealed the potency of probiotics in alleviating metabolic diseases associated with intestinal barrier dysfunction. However, an efficient model for screening probiotic strains against specific metabolic diseases has not been well developed. In the present study, a Caco-2 cell monolayer membrane model treated with tumor necrosis factor (TNF-α) or alcohol was used to evaluate the effect of 139 Lactobacillus strains on intestinal barrier function in vitro . We then selected 11 Lactobacillus strains with different regulatory abilities on the gut barrier to determine their effect against ovariectomy-induced osteoporosis or chronic alcoholic liver injury in vivo . Our results showed that the Pearson coefficient between the data of cell and animal models were 0.82 and −0.97 for the protection of probiotics against osteoporosis and alcoholic liver disease, respectively, suggesting the reliability of the cell model to simulate the in vivo protective effects of probiotics. This study established a potential in vitro approach based on a Caco-2 cell monolayer membrane model for the efficient screening of potential probiotics against specific metabolic diseases such as osteoporosis and chronic alcoholic liver disease.

Screening of novel probiotics with intestinal peristalsis-promoting potential based on in vitro and in vivo investigations

Constipation is a widespread gastrointestinal issue. This work aimed to investigate anti-constipation capacities of 9 novel strains of Lactobacillus and Bifidobacterium using in vitro experiments for initial exploration and then further confirmed through in vivo models including both zebrafish and mice. The in vitro experimental results revealed that L. plantarum T34 and L. paracasei YJ10 could survive under the simulated gastrointestinal tract conditions as standard strain L. rhamnosus (LGG) did. L. paracasei YJ10 and L. casei Lc showed the highest 22 h's aggregation rate. L. rhamnosus W1 showed the highest coaggregation rate with E. coli and with S. aureus. T34 had the largest inhibition zones against S. typhimurium and L. Monocytogenes. The highest adhesion rates with HT-29 cells were L. casei Lc, LGG and W1. Principal component analysis (PCA) and Fuzzy synthetic evaluation (FSE) were performed to evaluate the in vitro probiotic potential of the 9 strains comprehensively. The order of scores on in vitro probiotic property from high to low was as follows: T34, W1, YJ10, Lc, LGG, SLT, SS, Lb, YN4 and LQSQ. The subsequent in vivo experiment of zebrafish further confirmed T34, W1 and YJ10 have better anti-constipation ability compared to other strains. Furthermore, T34 relieve loperamide-induced constipation by promoting gut transit in the mice model. In conclusion, T34 was demonstrated to prevent constipation and may be suggested for use in food and pharmaceutical goods.

Effects of Bifidobacteria bifidum strains on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced acute colitis and its potential mechanism

Microbiota-based therapies for improving symptoms of Crohn's disease (CD) are receiving increasing attention. Probiotics and second-generation probiotics can potentially prevent this disease. However, the therapeutic action and underlying molecular mechanisms of probiotics remain largely unknown. Efficient screening of probiotics is also challenging. In this study, we screened eight B. bifidum strains with CD-relieving potential using a 2,4,6-trinitrobenzene sulfonic acid (TNBS) colitis mouse model. We also observed that B. bifidum CJ238 could prevent but not cure the colitis-symptoms (weight loss, colon shortening and connective tissue hyperplasia) in mice model. The 16S rRNA sequencing data showed that supplementation with B. bifidum did not alter the composition of the intestinal microbiota. B. bifidum CJ238 administration also provided full protection against acute colitis in pseudo germ-free mice. Therefore, we infered that the protective effect of B. bifidum strains does not depend on their interaction with the gut microbiota. Furthermore, heat-killed (95 °C for 20min) B. bifidum cells (109 CFU/mouse) also protected mice against acute colitis. In-vitro adhesion and immunomodulatory activities of the B. bifidum strains were measured. Combined with the in-vivo results, the anti-colitis effect of B. bifidum was positively associated with its strong anti-inflammatory and adhesion capacity in-vitro. This study provides insights into the in-vitro screening and clinical application of probiotics in CD prevention.

The screening of probiotic lactic acid bacteria from honey of stingless bee from West Sumatra, Indonesia and using as starter culture

Abstract. Melia S, Aritonang SN, Juliyarsi I, Kurnia YF, Rusdimansyah, Hernita VO. 2022. The screening of probiotic lactic acid bacteria from honey of stingless bee from West Sumatra, Indonesia and using as starter culture. Biodiversitas 23: 6379-6385. This study aimed to isolate probiotic lactic acid bacteria (LAB) from stingless bee honey (Galo-galo) and apply it as a starter culture. This research used stingless bee honey (Galo-galo) from west Sumatra, Indonesia. There are 6 types of honey bees, namely Tetragonula sarawakensis (TS), Tetragonula testaceitarsis (TT), Tetragonula minangkabau (MK), Tetrigona binghami (TB), Geniotrigona thoracica (TR) and Heterotrigona itama (IT). The screening of probiotics was evaluated as the LAB isolates' ability to resist acid (pH 3), bile salts (0xgall 0.5%), and antimicrobial activity against pathogenic bacteria. Based on the probiotic selection, the TB1 isolate from Tetrigona binghami honey had an acid tolerance of 82.75%, bile salt tolerance of 94.44%, and the highest antimicrobial activity against pathogenic bacteria with more excellent resistance than antibiotics. The identification with 16S rRNA showed that the TB1 bacterial isolate had 100% similarity with Lactobacillus plantarum SN13TFurthermore, starter culture inoculated with 6% L.plantarum SN13T met the starter culture parameters, with a pH of 4.7, titratable acidity of 1.46%, and lactic acid bacteria counts of 9.0 x 109 CFU/mL. L.plantarum SN13T is a candidate probiotic bacteria isolated from the stingless bee honey (Tetrigona binghami). This bacteria has the potential to be developed as a starter for fermented milk processing in the food industry.

Identification of a new probiotic strain, Lactiplantibacillus plantarum VHProbi® V38, and its use as an oral health agent.

Probiotics can be used to treat oral diseases such as dental caries, gingivitis, periodontitis, and halitosis. This study screened for strains capable of inhibiting Streptococcus mutans,one of the primary pathogenic bacteria responsible for dental caries by agar diffusion in different samples. Strain identification was performed by 16S rDNA sequencing and the API 50CH system. The potential functions of the strains in terms of oral health properties were also tested by agglutination assays, growth inhibition assays, adhesion assays, biofilm removal assays and inhibition of adhesion in human primary gingival epithelial (HPGE) cells assays. This study identified a probiotic strain from fermented cabbages that has a strong inhibitory effect on Streptococcus mutans. The API 50CH system and 16S rDNA sequencing verified that this was a new strain and it was given the name, Lactiplantibacillus plantarum VHProbi®V38. Agglutination, growth inhibition and adhesion, and biofilm removal tests indicated that L. plantarum VHProbi® V38 inhibited and reduced S. mutans. This probiotic was shown to have a broad antibacterial spectrum, simultaneously inhibiting the growth of periodontal pathogenic bacteria such as Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum. After 2 hours of co-cultivation with these pathogens, L. plantarum VHProbi® V38 was able to significantly reduce pathogens adhesion on human primary gingival epithelial (HPGE) cells. These findings suggest that L. plantarum VHProbi® V38 could potentially prevent and treat periodontal diseases caused by these pathogenic bacteria. L. plantarum VHProbi® V38 also adheres strongly to HPGE cells and thus has potential as an oral probiotic. This study describes new methods that can be used to aid the screening and identification of oral probiotics.

Screening of antagonistic bacteria against Flavobacterium columnus and its effects on growth performance and immune function of Carassius auratus

With the popularization of modern intensive farming models, aquatic animals are more prone to outbreaks of various diseases. Due to the abuse of antibiotics, drug resistance among pathogenic bacteria and the deterioration of the water environment continue to occur. Therefore, it is essential to find probiotics that can effectively resist the erosion of pathogenic microorganisms, enhance fish's immunity, and promote fish's growth as an alternative to antibiotics.In this experiment, two strains of probiotic bacteria antagonistic to Flavobacterium columnar were isolated from pond water samples. They were identified as Bacillus amyloliquefaciens and Acinetobacter johnsonii by 16S rRNA gene sequence analysis. To further analyze the physiological function of the two probiotics, we added Bacillus amyloliquefaciens, Acinetobacter johnsonii and two strain mixtures to the base feed and fed crucian carp separately. The results found that after 40 days of feeding, the growth performance of wild crucian carp and total protein(TP), globulin(GLO), albumin(ALB) and total bile acid(TBA) had no significant effect. However, Bacillus amyloliquefaciens could significantly reduce total bilirubin(TBiL), direct bilirubin(DBiL), indirect bilirubin(IBiL) and hypersensitive C-reactive protein(hs-CRP) in the serum of crucian carp. The addition of Acinetobacter johnsonii significantly reduced the content of indirect bilirubin(IBiL), acetonitrile/glutamate(A/G) and hs-CRP in the serum of wild crucian carp, which could effectively increase the range of superoxide dismutase(SOD) and reduce the production of malondialdehyde(MDA). After adding the mixed bacteria, Immunoglobulin M(IgM) in the serum of wild crucian carp increased significantly. In addition, the detection of intraperitoneal injection at 24 h, 48 h and 96 h was found to have no significant effect on the serum biochemical indicators of wild crucian carp.The above results show that adding Acinetobacter johnsonii can enhance crucian carp's anti-inflammatory, immunity and antioxidant properties. Therefore, the two bacteria can be used as potential probiotics for wild crucian carp. The research on this topic is of great significance for the screening of water probiotics, improving the water environment, optimizing the intestinal flora of fish, and improving the immunity of fish. At the same time, it provides new ideas for promoting healthy fish farming.

Application of Probiotics for Environmentally Friendly and Sustainable Aquaculture: A Review

Aquaculture plays an important role in food production for the world population and at the same time for the livelihood of the most needed globally. The concerns about sustainability and ecological health are growing in this extremely diversified sector just like in the whole agriculture industry. The use of probiotics in aquaculture already has a long history and has served from the beginning the goals of more sustainable production; however, the expansion of intensive systems along with global climate change produces new challenges. The present work aims to provide an overview of the most relevant literature. Firstly, the microbiome of aquatic animals and its functioning is surveyed followed by the aims and methods of probiotic application. The screening and testing of novel probiotics are also assessed as well as the scientific and technical novelties in probiotics research. The mainstream development in probiotic research aims to serve the sustainability of aquaculture in all respects including traditional animal health, feed efficiency, and environmental issues. New state-of-the-art techniques may lead to a future paradigm change in aquaculture under the aegis of the Blue Revolution.

Screening of Lactobacillus from breast milk and infant feces and evaluation of their bile salt tolerance

The intestinal bile salt concentration of infants is lower than that of adults, and the necessary bile salt tolerance of probiotics for infants remains unclear. In this study, Lactobacillus strains were isolated from breast milk and infant feces. The strains with better bile salt tolerance were screened, and their bile salt tolerance was compared with Lactobacillus strains from the adult intestine. The results showed that the bile salt concentration had a better distinguishing effect when it was 0.075 and 0.1%. Among the 28 strains of Lactobacillus with better bile salt tolerance, there were 16 strains of Lactobacillus plantarum, among which eight strains had greater than 70% survival under 0.075% bile salt and two strains had more than 50% survival under 0.1% bile salt. L. plantarum strains isolated from breast milk and infant feces had a significantly lower survival rate than those isolated from the adult intestine (P &lt; 0.05) under 0.1% bile salt, while there was no significant difference in the survival rate under 0.075% bile salt (P &gt; 0.05). Therefore, the demands for bile salt tolerance of probiotics for infants might be lower than that for adults. It is suggested that the standard for the screening of probiotics from breast milk and infant feces should differ from adults.

Challenging Approaches of lactic acid bacteria for the preservation of selected fruits

Edible fruits and vegetables are easily degraded or denatured by several reasons especially from environmental factors. Due that the shelf life of plant materials are drastically reduced. It may affect the economic value of individual persons. From this research work was undertaken few selected curd samples, tomato samples and grapes from various areas for selecting significant lactic acid bacteria (LAB). Screening of probiotics was done by the detection of antagonistic activities, acid and bile salt tolerance test, antibiotic resistance test and sensitivity pattern and antimicrobial activity study. In the present studies, total 52 fruit flora bacterial cultures were isolated from two different site oriented tomato and grapes.LAB colonies in 10-5 dilution were expressed good loading capacity in curd sample, grapes and tomato. In antagonistic activity, Lactobacillus delburecki and Lactobacillus sp. were observed highest zone against Shigella sp. From this, Lacto bacillus delburecki and Lactobacillus sp. were actively preserved the selected vegetables. They were increased the shelf-life and reduced the degradation of the samples