Potential Probiotic Strains Research Articles

Potential Functional Snacks: Date Fruit Bars Supplemented by Different Species of Lactobacillus spp.

The influence of the addition of four different potential probiotic strains, Lactiplantibacillus plantarum subsp. plantarum (L. plantarum), Lactobacillus delbruekii subsp. bulgaricus (L. bulgaricus), Lactobacillus acidophilus (L. acidophilus) and Lactinocaseibacillus rhamnosus (L. rhamnosus), in date fruit-based products was investigated in order to evaluate the possibility of producing a functional snack. All bacterial strains tested were able to grow in date fruit palp, reaching probiotic concentrations ranging from 3.1 × 109 to 4.9 × 109 colony-forming units after 48 h of fermentation, and the pH was reduced to 3.5–3.7 or below. The viability of inoculated probiotic bacteria after 4 weeks of storage at 4 °C was slightly reduced. Some biochemical features of the fermented snacks, such as the total phenolic content (TPC), antioxidant activity and detailed polyphenolic profile, were also evaluated. After fermentation, changes in the polyphenol profile in terms of increased free phenolic compounds and related activity were observed. These results may be attributed to the enzymatic activity of Lactobacillus spp. in catalyzing both the release of bioactive components from the food matrix and the remodeling of polyphenolic composition in favor of more bioaccessible molecules. These positive effects were more evident when the snack were fermented with L. rhamnosus. Our results suggest the use of lactic acid fermentation as an approach to enhance the nutritional value of functional foods, resulting in the enhancement of their health-promoting potential.

Screening of New Potential Probiotics Strains against Photobacterium damselae Subsp. piscicida for Marine Aquaculture.

Simple SummaryMarine aquaculture has been one of the fastest growing animal production sectors in the last thirty years worldwide. On intensive farms, 10% of the population dies exclusively from pathogen activity, and Photobacterium damselae subsp. piscicida is one of the major infectious agents causing marine fish mortality. The purpose of this study is to obtain potential probiotic strains against pasteurellosis, in order to limit the use of chemotherapy, avoiding the environmental impact generated by the abusive use of these products. Bacterial strains isolated from different fish species were characterized in vitro and in vivo to determine their probiotic properties. Of the total number of strains isolated, only one showed excellent results to continue its characterization in vivo against this marine pathogen. The use of this strain as a possible probiotic for marine aquaculture will be in progress in future studies.On intensive fish farms, 10% of the population dies exclusively from pathogens, and Photobacterium damselae subsp. Piscicida (Ph. damselae subsp. Piscicida), the bacteria causing pasteurellosis in marine aquaculture, is one of the major pathogens involved. The objective of this study was to obtain new probiotic strains against pasteurellosis in order to limit the use of chemotherapy, avoiding the environmental repercussions generated by the abusive use of these products. In this study, 122 strains were isolated from the gills and intestines of different marine fish species and were later evaluated in vitro to demonstrate the production of antagonistic effects, the production of antibacterial substances, adhesion and growth to mucus, resistance to bile and resistance to pH gradients, as well as its harmlessness and the dynamic of expression of immune-related genes by real-time PCR after administration of the potential probiotic in the fish diet. Only 1/122 strains showed excellent results to be considered as a potential probiotic strain and continue its characterization against Ph. damselae subsp. piscicida to determine its protective effect and elucidating in future studies its use as a possible probiotic strain for marine aquaculture.

Isolation and phenotypic and genotypic characterization of the potential probiotic strains of Lactobacillus from the Iranian population

Among different causes of inflammatory bowel disease (IBD), the imbalance of the gut microbiome (dysbiosis) is one of the main reasons for the development of the disease. Probiotics are live microorganisms that can maintain gut microbiota by different mechanisms. We aimed to isolate and characterize the potential probiotic strains of Lactobacillus from the Iranian population. This cross-sectional study was conducted on faecal samples of 83 volunteer individuals living in Guilan Province, North Iran. The primary identification of Lactobacillus strains was performed by standard microbiological tests and confirmed by amplification of 16s rRNA specific primers. The acid and bile salt tolerance were assessed for all recovered strains. Also, the presence of 3 bacteriocins encoding genes was investigated by the PCR method. Totally, 42 samples were positive for Lactobacillus species. Acid and bile resistance assay showed that 67% and 33% of strains were resistant to acid and bile salt stress, respectively. Therefore, we found out that 28% of our Lactobacillus strains have the ability for resistance to acid and bile conditions. PCR results revealed that the prevalence of gassericin A, plantaricin S, lactacin bacteriocin genes were 16.6%, 12%, and 9.5%, respectively. Meanwhile, 5 out of 12 Lactobacillus strains that were resistant to acid and bile conditions contained one of the gassericin or plantaricin bacteriocins. We isolated 42 potential probiotic strains of Lactobacillus, of which the results of 5 strains were more promising and can be considered as potential probiotics sources for future functional products.

English

Breast feeding has critical effects on the newborns and either mother’s health. Some of such health-improving effects of the mother’s milk is associated with the beneficial microbes, lactic acid bacteria (LAB), which are normally present in the mother’s milk. Thus, human milk-associated lactobacilli were isolated in this study and some of their probiotic properties was investigated. Afterwards, Lactobacillus strains were screened for low pH and bile acids tolerance. Molecular identification was carried out using 16SrDNA and polymerase chain reaction (PCR). Antibiotic resistance was evaluated with disk diffusion assay and the inhibitory effect of isolates on pathogenic bacteria was examined with well assay and zone inhibition. Isolation experiments resulted in 122 human milk- associated lactobacilli belonging to 12 species. The most dominant species was Lactobacillus casei followed by Lactobacillus fermentum, Lactobacillus plantarum and Lactobacillus gasser, respectively. Screening for probiotic properties showed that 19 isolates, belonging to, Lactobacillus, have interesting probiotic characteristics. The most prevalent antibiotic resistance was observed in case of vancomycin (63.15%) and no drug resistance was detected for chloramphenicol, penicillin, rifampin (0%). Three Lactobacillus strains, designated as L4, L14 and L16, were found as potential probiotic strains since they have indicated promising inhibitory effects against the studied pathogenic bacterial strains. Our results shed light on the considerable diversity of lactobacilli in human breast milk. Furthermore, the candidate probiotic strains detected in this research might be used as potential probiotic strains.   Key words: Breast milk, Lactobacillus, probiotics, inhibitory effect, polymerase chain reaction.

Evaluation of probiotic properties of Lysinibacillus macroides under in vitro conditions and culture of Cyprinus carpio on growth parameters.

Cyprinus carpio is an important freshwater fish in aquaculture. It was used for the isolation of potential probiotic strain for aquaculture applications. The most dominant strain was isolated on MRS agar from the gastrointestinal (GI) of C. carpio and identified as Lysinibacillus macroides using molecular marker 16S rRNA gene. Various probiotic properties such as acid and bile tolerance and antibiotic susceptibility were analysed under in vitro conditions. Further, formulate pelletized feed using probiotic (L. macroides) in different concentrations (2, 4, 6 and 8%). Rearing of C. carpio was carried out 45days and fed with formulated feed. The highest length (5.14 ± 0.07cm) and weight (3.56 ± 0.07g) of C. carpio fingerlings was recorded in the 8% LM probiotic pelletized feed, while in fingerlings fed with control showed lower in the length (3.02 ± 0.13cm) and the weight (0.92 ± 0.04g) on the 45th day of the experiment. Both percentage of weight gain (PWG) and specific growth rate (SGR) were significantly increased (P < 0.05) of C. carpio fingerlings fed with probiotic feed compared to control feed. Hence, the use of probiotic bacteria could be an encouraging alternative feed for future endeavours in the field of aquaculture. In conclusion, L. macroides can serve as probiotic for sustainable, competitive and promising beneficial bacteria to aquaculture industry.

Characterisation of a potential probiotic strain Paracoccus marcusii KGP and its application in whey bioremediation.

Whey, the main by-product obtained from the manufacture of cheese, which contains a very high organic load (mainly due to the lactose content), is not easily degradable and creates concern over environmental issues. Hydrolysis of lactose present in whey and conversion of whey lactose into valuable products such as bioethanol, sweet syrup, and animal feed offers the possibility of whey bioremediation. The increasing need for bioremediation in the dairy industry has compelled researchers to search for a novel source of β-galactosidase with diverse properties. In the present study, the bacterium Paracoccus marcusii KGP producing β-galactosidase was subjected to morphological, biochemical, and probiotic characterisation. The bacterial isolate was found to be non-pathogenic and resistant to low pH (3 and 4), bile salts (0.2%), salt (10%), pepsin (at pH 3), and pancreatin (at pH 8). Further characterisation revealed that the bacteria have a good auto-aggregation ability (40% at 24h), higher hydrophobicity (chloroform-60%, xylene-50%, and ethyl acetate-40%) and a broad spectrum of antibiotic susceptibility. The highest growth of P. marcusii KGP was achieved at pH 7 and 28°C, and the yeast extract, galactose, and MgSO4 were the best for the growth of the bacterial cells. The bacterium KGP was able to utilise whey as a substrate for its growth with good β-galactosidase production potential. Furthermore, the β-galactosidase extracted from the isolate KGP could hydrolyse 47% whey lactose efficiently at 50°C. The study thus reveals the potential application of β-galactosidase from P. marcusii KGP in whey bioremediation.

Characterization and Selection of Lactobacillus plantarum and Lactobacillus paracasei for prevention of oral bacterial infections from Chinese pickle

The oral infections were mainly caused by Streptococci and Staphylococcus aureus. Antibiotic therapies can eliminate these harmful bacteria. However, it can break beneficial microbes and lead to the persistence of resistant strains. The objective of our study was to select potential probiotic strains for the prevention of oral bacterial infections and evaluate their potential probiotic properties in oral cavity. AR113 (Lactobacillus plantarum) and AR340 (Lactobacillus paracasei) with significantly antimicrobial β-hemolytic streptococci and Staphylococcus aureus activity were isolated from Chinese pickle through agar well diffusion assay. Through the analyses of probiotic properties in antibiofilm, lysozyme and hydrogen peroxide tolerance, bacterial surface properties, adherence ability, tooth degradation and anti-inflammatory activity, the AR113 and AR340 showed anti-adhesion activity of 45.2–71.1% and 20.3–56.8% against β-hemolytic streptococci and 15.4–52.6% and 30.7–65.9% against Staphylococcus aureus, respectively, at different concentration. The two strains with high hydrophobicity, autoaggregation and survival rate adhered strongly to FaDu cells. AR113 and AR340 exhibited low calcium released from teeth (0.04 μg/mL and 0.03 μg/mL, respectively). ELISA analysis showed that AR113 and AR340 significantly inhibited the LPS-induced increase of NO and TNF-α expression. Strains-fermented skim milk inhibited the growth of β-hemolytic streptococci or Staphylococcus aureus. AR113 and AR340 were considered as probiotic candidates because of their higher antibacterial activity against some oral pathogenic bacteria, no potential of primitive cariogenicity. These candidates were expected as new probiotics with potential oral health benefits and no harmful effects.

Extractable surface proteins of indigenous probiotic strains confer anti-adhesion knack and protect against methicillin-resistant Staphylococcus aureus induced epithelial hyperpermeability in HT-29 cell line

Probiotic intervention has been long believed to have beneficial effects on human health by curbing the intestinal colonization of pathogens. However, the application of live probiotics therapy may not be an ideal approach to circumvent the infections of superbug origin due to the risk of horizontal antibiotic resistance genes transfer. In this study, the anti-adhesion ability of extractable cell surface proteins from two indigenous potential probiotic strains (Lactiplantibacillus plantarum A5 and Limosilactobacillus fermentum Lf1) and two standard reference strains (Lactobacillus acidophilus NCFM and Lacticaseibacillus rhamnosus LGG) was evaluated against clinical isolates of Methicillin-Resistant Staphylococcus aureus (MRSA) on porcine gastric mucin and HT-29 cells. The surface proteins from the probiotic strains were extracted by treatment with 5 M lithium chloride. The surface protein quantification and SDS-PAGE profiling indicated that the yield and protein patterns were strain-specific. Surface proteins significantly hampered the mucoadhesion of MRSA isolates via protective, competitive, and displacement. Similarly, the treatment with surface proteins probiotic strains displayed anti-adhesion against MRSA isolates on HT-29 cells without affecting the viability of the cell line. Surface proteins treatment to the confluent monolayer of HT-29 cells maintained the epithelial integrity; however, MRSA isolates (109 cells/mL) showed considerable alteration in the epithelial integrity by exacerbating the FITC-dextran transflux. Contrarily, the co-treatment with surface proteins with MRSA isolates significantly lowered the FITC-dextran transflux across the differentiated HT-29 monolayer. Overall, the findings of this study suggest that probiotic-derived surface proteins could be the novel biotherapeutics to combat the MRSA colonization and their concomitant intestinal infections.

Determination of the biosafety of potential probiotic Enterococcus faecalis and Enterococcus faecium strains isolated from traditional white cheeses

The aims of this study were to characterize antibiotic resistance, determination of genotypic and phenotypic virulence characters; and to evaluate the safety of 12 Enterococcus faecalis and 8Enterococcus faecium strains isolated from Iranian and Turkish white cheeses. All strains were researched for production capability of cytolysin and gelatinase, biofilm formation and sensitivity against ten antibiotics. The presence of vancomycin resistance genes and virulence factors genes like cylA and cylB, esp, agg, asa1, EfaAfs, EfaAfm, cob, ccf, and hly were determined by polymerase chain reaction and sequence analysis. All the investigated strains were resistant to at least one class of antibiotic, and 40% of the strains were classified as multi drug resistant. E. faecalis RI 11, RI 17, RI 21 strains demonstrated both gelatinase and biofilm activities. Moreover, there was a significant correlation between gelatinase activity and the presence of gelE (P < 0.05). While ccf and asa1 genes were determined in all strains, efaAfm and clyB genes were not found in any strains. E. faecium RI 56, RI 58 and RI 59 strains were found to contain different molecular sizes of plasmid DNA. The phenotypic and genotypic characteristics of E. faecalis and E. faecium strains were determined in terms of functional and safety perspectives.

Characterization of Iturin V, a Novel Antimicrobial Lipopeptide from a Potential Probiotic Strain Lactobacillus sp. M31

Members of lactic acid bacteria group are known to produce various antimicrobial substances. Cyclic lipopeptides are one such potent class of amphipathic natural biosurfactants that exhibit bactericidal and immunomodulatory properties. In this study, we aimed to investigate antimicrobial and immunomodulatory activities of a lipopeptide secreted by a LAB isolate strain M31 identified as a member of the genus Lactobacillus. The lipopeptide that was purified using a combination of chromatographic techniques and matrix-assisted laser desorption/ionization-time of flight of pure lipopeptide displayed a molecular weight of 1002Da. MS/MS analysis confirmed the presence of 7 amino acids (Asp-Tyr-Asp-Val-Pro-Asp-Ser) and a C13 beta-hydroxy fatty acid. The amino acid composition assigned lipopeptide to iturin class. However, the replacement of Gln with Val revealed it to represent a novel iturin named as iturin V. Iturin V showed antibacterial activity and did not cause hemolysis or cytotoxicity upto 125µg/mL. It induced secretion of pro-inflammatory cytokines TNF-alpha and IL-12 in murine dendritic cells. Probiotic features of strain M31 coupled with notable activity of iturin V against species of the genera Pseudomonas and Vibrio suggest that strain M31 has potential application for pathogen intervention treatments in processing of aquatic food products.

Lactobacillus reuteri TSR332 and Lactobacillus fermentum TSF331 stabilize serum uric acid levels and prevent hyperuricemia in rats.

BackgroundUric acid (UA) is the end product of purine metabolism in the liver and is excreted by the kidneys. When purine metabolism is impaired, the serum UA level will be elevated (hyperuricemia) and eventually lead to gout. During evolution, humans and some primates have lost the gene encoding uricase, which is vital in UA metabolism. With the advances of human society, the prevalence of hyperuricemia has dramatically increased because of the refined food culture. Hyperuricemia can be controlled by drugs, such as allopurinol and probenecid. However, these drugs have no preventive effect and are associated with unpleasant side effects. An increasing number of probiotic strains, which are able to regulate host metabolism and prevent chronic diseases without harmful side effects, have been characterized. The identification of probiotic strains, which are able to exert beneficial effects on UA metabolism, will provide an alternative healthcare strategy for patients with hyperuricemia, especially for those who are allergic to anti-hyperuricemia drugs.MethodsTo elicit hyperuricemia, rats in the symptom control group (HP) were injected with potassium oxonate and fed a high-purine diet. Rats in the probiotic groups received the high-purine diet, oxonate injection, and supplements of probiotic strains TSR332, TSF331, or La322. Rats in the blank control group (C) received a standard diet (AIN-93G) and oxonate injection.ResultsPurine-utilizing strains of probiotics were screened using high-pressure liquid chromatography (HPLC) in vitro, and the lowering effect on serum UA levels was analyzed in hyperuricemia rats in vivo. We found that Lactobacillus reuteri strain TSR332 and Lactobacillus fermentum strain TSF331 displayed significantly strong assimilation of inosine (90%; p = 0.00003 and 59%; p = 0.00545, respectively) and guanosine (78%; p = 0.00012 and 51%; p = 0.00062, respectively) within 30 min in vitro. Further animal studies revealed that serum UA levels were significantly reduced by 60% (p = 0.00169) and 30% (p = 0.00912), respectively, in hyperuricemic rats treated with TSR332 and TSF331 for 8 days. Remarkably, TSR332 ameliorated the occurrence of hyperuricemia, and no evident side effects were observed. Overall, our study indicates that TSR332 and TSF331 are potential functional probiotic strains for controlling the development of hyperuricemia.

Actinonin resistance of pathogenic Vibrio anguillarum in aquaculture

Drug-resistant bacteria are an increasingly serious threat to the aquaculture industry. In order to develop new methods to combat these bacteria, it is necessary to first understand their mechanisms of drug resistance. We previously isolated a potential probiotic strain, Streptomyces sp. NHF165, which produced cytotoxic actinonin against the aquaculture pathogen Vibrio anguillarum. In this study, a spontaneous V. anguillarum mutant with an eight-fold increased MIC for actinonin was characterized for elucidation of actinonin resistance mechanisms. Transcriptomic analysis revealed significant up-regulation of genes related to anaerobic respiratory (nap and tor) and down-regulation of genes involved in anaerobic respiration (nqr, sdh and frd) in mutant strains. Meanwhile, no mutations in bacterial respiration genes or translation initiation genes (the proposed actinonin targeted pathway) were detected by whole genome resequencing analysis. A series of experiments confirmed that actinonin-resistance in the mutant strain was associated with respiration. When aerobic respiration was chemically disrupted by CCCP, the growth of wild-type V. anguillarum changed significantly, with a 11.74-fold increase in cell density under actinonin treatment. For anaerobic respiration, an increased nitrate reductase activity was detected in mutant cells by addition of an exogenous electron donor. Noteworthy was the finding that nitrate inhibited the growth of the wild-type strain but promoted the growth of the mutant. Futhermore, the product of nitrate-dependent anaerobic respiration, nitrite, did not arrest the growth of mutant V. anguillarum, which was contrary to previous reports and might exacerbate the formation of vibriosis. Finally, we showed that chemical inhibition of nitrate reductase could restore the susceptibility of mutant V. anguillarum to actinonin. Together these data demonstrate that the combined use of an anaerobic-respiratory inhibitor and an antibiotic might be a promising approach for the treatment of drug-resistant bacteria in aquaculture.

Characterization of potential probiotic strain, L. reuteri B2, and its microencapsulation using alginate-based biopolymers

In this study, Lactobacillus reuteri B2 was isolated from the feces of C57BL/6 mice and assessed on probiotic activity. L. reuteri B2 was identified by 16S rDNA sequencing, which the cell viability in acidic conditions at pH 2.0 was 64% after 2 h, and in the presents of 0.30% of the bile salts, after 6 h, was 37%. Antimicrobial assay with L. reuteri B2 showed maximum diameters against Klebsiela oxytoca J7 (12.5 ± 0.71 mm). We further hypothesized if L. reuteri B2 strain in the free form can survive all conditions in the gastrointestinal tract (GIT) then the utilization of the appropriate biomaterials would ameliorate its stability and viability in GIT. L. reuteri B2 was microencapsulated into sodium alginate-(Na-alg) and different content of Na-alg and sodium maleate (SM) beads. Characterization materials enveloped their thermal characteristics (TGA/DTA analysis) and structure using: scanning electron microscopy (SEM), FTIR, and particle size distribution. The high survival rate of L. reuteri B2 at low pH from 2.0 to 4.0 and in the presence of the bile salts, at concentrations up to 0.30%, was obtained. L. reuteri B2 showed strong antimicrobial activity and the best protection microencapsulated with Na-alg + SM in simulated gastric juices (SGJ).

Probiogenomics of Lactobacillus delbrueckii subsp. lactis CIDCA 133: In Silico, In Vitro, and In Vivo Approaches.

Lactobacillus delbrueckii subsp. lactis CIDCA 133 (CIDCA 133) has been reported as a potential probiotic strain, presenting immunomodulatory properties. This study investigated the possible genes and molecular mechanism involved with a probiotic profile of CIDCA 133 through a genomic approach associated with in vitro and in vivo analysis. Genomic analysis corroborates the species identification carried out by the classical microbiological method. Phenotypic assays demonstrated that the CIDCA 133 strain could survive acidic, osmotic, and thermic stresses. In addition, this strain shows antibacterial activity against Salmonella Typhimurium and presents immunostimulatory properties capable of upregulating anti-inflammatory cytokines Il10 and Tgfb1 gene expression through inhibition of Nfkb1 gene expression. These reported effects can be associated with secreted, membrane/exposed to the surface and cytoplasmic proteins, and bacteriocins-encoding genes predicted in silico. Furthermore, our results showed the genes and the possible mechanisms used by CIDCA 133 to produce their beneficial host effects and highlight its use as a probiotic microorganism.

Screening of intestinal probiotics and the effects of feeding probiotics on the digestive enzyme activity, immune, intestinal flora and WSSV resistance of Procambarus clarkii

In this experiment, a potential probiotic strain A23 with high antimicrobial activity against common aquatic pathogens and extracellular enzyme production was isolated from the intestine of healthy Procambarus clarkii. Biochemical and 16S rDNA sequencing analysis identified A23 as Bacillus amyloliquefaciens, and a haemolytic test and antibiotic susceptibility test were carried out on strain A23 to determine its safety. First, the whole genome of B. amyloliquefaciens A23 was determined to explore its mechanism of action. The results showed that the total length of the genome was 3,974,398 bp, the GC content was 46.56%, and 3843 genes were encoded, including 27 rRNA operons and 86 transfer RNA genes. Three bacilysin-related genes and 10 antimicrobial peptide (AMP)-related genes were found through manual inspection. Second, we evaluated the beneficial effects of strain A23 in P. clarkii by performing in vivo feeding experiments. The results showed that probiotic supplementation could effectively enhance the intestinal digestive enzyme activities, innate immune enzyme activities and white spot syndrome virus (WSSV) resistance of P. clarkii. Finally, the intestinal microbial community and diversity of crayfish were compared and analyzed by high-throughput sequencing. At the phylum level, the abundance of Proteobacteria decreased with 108 CFU/g probiotics supplement, while the abundance of Firmicutes and Bacteroides increased. The Shannon index of the intestinal microorganism community of the 108 CFU/g probiotic supplementation group was significantly higher than that of the control group, indicateding that 108 CFU/g probiotic supplementation enhanced intestinal microbial diversity. The results from this study demonstrated that B. amyloliquefaciens A23 is a promising probiotic candidate that provides multiple benefits for crayfish cultivation.

Emmer-Based Beverage Fortified with Fruit Juices

Nowadays, there is a growing consumer demand for non-dairy functional foods due to several health issues related to milk and dairy consumption and increasing vegetarianism. Following that trend, in the present study emmer-based beverages were developed after flour gelatinization, fortification with fruit juices (blueberry, aronia, and grape) and fermentation with the potential probiotic strain Lactiplantibacillus plantarum 2035. The produced beverages were subjected to a 4-week storage at 4 °C. The addition of juices significantly affected the physicochemical characteristics of the beverages, while resulting in increased red color. Total phenolic content (22.3–31.9 mg gallic acid equivalents 100 g−1) and antioxidant activity (94–136 μmol Trolox equivalents 100 g−1) were significantly higher in the case of aronia juice followed by blueberry and grape juice. All beverages showed high values of apparent viscosity and water-holding capacity. Lactiplantibacillus plantarum 2035 retained high viable counts during storage especially in beverages with fruit juices (&gt;108 cells g−1 up to 21st day) revealing a positive effect of the juices. The obtained results show that emmer-based beverages fortified with fruit juices (aronia, blueberry, and grape) have a great potential as carriers of probiotics, prebiotics and other functional compounds and may be served as an ideal alternative to dairy products.

Lozenges with probiotic strains enhance oral immune response and health.

Probiotics participate in regulating oral microbiota and reducing the prevalence of oral diseases; however, clinical research on probiotics is insufficient. Therefore, in this study, we performed in vitro screening of potential oral protective probiotic strains and then evaluated the clinical efficacy of the selected strains on maintaining oral health. Fifty healthy individuals were recruited and randomly assigned into the placebo group and probiotics group, which included three strains of probiotics, Lactobacillus salivarius subs. salicinius AP-32, Lactobacillus paracasei ET-66, and Lactobacillus plantarum LPL28. Each group was blindly administered placebo or probiotics for four weeks. Next-generation sequencing results showed that the oral microbiota of Lactobacillus salivarius in the oral cavity were significantly increased in subjects supplemented with mixed probiotic lozenges. The anti-bacterial activities of viable probiotics were observed within two weeks. Both IgA levels and Lactobacillus and Bifidobacterium abundances in the oral cavity were significantly increased in the experimental groups, along with a reduced formation of plaque. Most participants reported that their oral health conditions and intestinal symptoms had improved. Overall, our clinical study suggests that oral probiotic lozenges may enhance oral immunity, modulate oral microbiota, and improve oral health.

Effects of potential probiotic strains LBKV-3 on Immune Cells responses in Malnutrite children: a double-blind, randomized,Controlled trial

ABSTRACT This study investigated the phagocytic cell response in malnourished children after oral feeding of a fermented product containing clinically proven probiotic strains of Lactobacillus acidophilus, LBKV-3. The bacterial strain is used as a probiotic for humans to test its effect on immune cell activity in undernourished children below 8 years of age. To study the immune cell activity, implantation abilities of the culture in the GI tract of malnourished children, forty-five children of 6–7 and 7–8 years were randomly selected and distributed in three groups, each comprising 15 children in each of the age group. The test group of the children was receiving 100 g product volunteers/day of freshly prepared probiotic acidophilus milk containing 107 cfu/g of culture. The control group was receiving 100 g freshly prepared ”dahi” containing 107 cfu/g of the LAB while the blank group of the volunteers was receiving thermal processed (85° C/30 min) buffalo milk containing 5% fat and 10% SNF at the rate of 100 ml/day/volunteer. Feeding trial was continued for 12 weeks. Blood samples were collected at W2, W4, W8, and W12. The blood serum samples were analyzed for monocytes, neutrophils, basophils, and lymphocytes by BC-3000 + Auto Hematology Analyzer. In conclusion, consumption of PAM increased the proportion of immune cells, including monocytes, neutrophils, basophils, and lymphocytes, as well as their phagocytic activity in all age groups but proportion was significant in the test group of 7–8 years. The effects were higher during W12 compared to W2, W4, and W8, which suggest regulation of the immune system.

Functional Annotation Genome Unravels Potential Probiotic Bacillus velezensis Strain KMU01 from Traditional Korean Fermented Kimchi.

Bacillus velezensis strain KMU01 showing γ-glutamyltransferase activity as a probiotic candidate was isolated from kimchi. However, the genetic information on strain KMU01 was not clear. Therefore, the current investigation was undertaken to prove the probiotic traits of B. velezensis strain KMU01 through genomic analysis. Genomic analysis revealed that strain KMU01 did not encode enterotoxin genes and acquired antibiotic resistance genes. Strain KMU01 genome possessed survivability traits under extreme conditions such as in the presence of gastric acid, as well as several probiotic traits such as intestinal epithelium adhesion and the production of thiamine and essential amino acids. Potential genes for human health enhancement such as those for γ-glutamyltransferase, nattokinase, and bacteriocin production were also identified in the genome. As a starter candidate for food fermentation, the genome of KMU01 encoded for protease, amylase, and lipase genes. The complete genomic sequence of KMU01 will contribute to our understanding of the genetic basis of probiotic properties and allow for the assessment of the effectiveness of this strain as a starter or probiotic for use in the food industry.

Isolation of Probiotic Lactobacilli from Indigenous Yogurt and Cheese and Their Antagonistic Roles Against Foodborne Pathogens

Background: Probiotic bacteria are one of the useful dietary supplements for human health. The main reason for selecting probiotics is the lack of prolonged side effects. Objectives: This study aimed to isolate lactobacilli from traditional yogurt and cheese samples collected in Neyshabur city, Khorasan Razavi, Iran, and to characterize them using specific biochemical and molecular assays. Methods: The probiotic potency of bacteria was tested by resistance to acid, bile, NaCl, and organic acid production. Moreover, the antagonistic effects of the isolates were investigated against enteric pathogenic bacteria using the well diffusion method. Bacteriocin production was also investigated using the microtiter plate assay. Results: Four Lactobacillus spp. with &gt; 99% homology to L. reuteri, L. plantarum, and L. acidophilus, were isolated with probiotic potency. The quantitative measurements used in the study with the statistical analysis resulted in the interpretation of good effects against Clostridium perfringens, Salmonella typhi, Staphylococcus aureus, and Listeria monocytogenes. Our isolates exhibited bile salt hydrolase activity, excellent NaCl and acid tolerance (pH = 3), and bacteriocin production. Conclusions: Our results showed that Lactobacillus strains isolated from Neyshabur traditional cheese could be considered good potential probiotic strains and had more antagonistic activity against human pathogens when compared to other samples. Their antibacterial activity was associated with both bacteriocin and organic acids production, but they should be further investigated for their human health benefits.