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Bacterial vaginosis (BV) is a common vaginal disease associated with abnormal changes in the vaginal microbiome. Our previous study found that Lactobacillus rhamnosus has a good therapeutic effect on bacterial vaginosis by inhibiting the most prominent bacterium associated with BV, Gardnerella vaginalis. In this study, we show that acetic acid and lactic acid are the main substances in the cell-free supernatant (CFS) of L. rhamnosus that inhibit the growth of G. vaginalis. Further study on the mechanism showed that acetic acid and lactic acid alter the morphology of the G. vaginalis cells, eventually causing the cells to shrink or burst, resulting in exudation of their intracellular contents. In addition, these two organic acids also dissipate the membrane potential of bacterial cells, affecting their synthesis of ATP. A reduced activity of the Na+/K+-ATPase leads to abnormal ATP metabolism, and ultimately inhibits the growth and reproduction of G. vaginalis. Our study provides valuable information for the widespread application of L. rhamnosus in the treatment of bacterial vaginosis.

Hypercholesterolemia is a risk factor for cardiovascular diseases, and hence, reducing serum cholesterol levels could reduce the incidence. In this study, we ascertained the cholesterol-reducing potential of lactic acid bacteria (LAB) isolated from Korean fermented soybean paste. Live, resting, and dead cells of all the bacteria reduced cholesterol in liquid media in a strain-dependent manner. Live cells of Weissella cibaria SCCB2306, Pediococcus acidilactici SDL1402, P. acidilactici SDL1406, and Lactobacillus rhamnosus JDFM6 reduced the most cholesterol in liquid media by 78 ± 3%, 72 ± 3%, 76 ± 3%, 75 ± 5%, and 79 ± 2%, respectively. As the cholesterol levels in the media reduced, cell membrane lipids of P. acidilactici SDL1402, P. acidilactici SDL1406, and L. rhamnosus JDFM6 increased by 23.36 mg/mL, 6.53 mg/mL, and 8.14 mg/mL, respectively, indicating that cholesterol was incorporated into the bacteria cell membranes. All the bacteria displayed bile salt hydrolase activities in a strain-dependent manner. Though all four LAB significantly reduced cholesterol levels in Caenorhabditis elegans irrespective of the order of feeding, L. rhamnosus JDFM6 reduced the most cholesterol in vivo (up to 40% of ingested cholesterol). None of the four LAB hydrolyzed mucin or gelatin and none was toxic to C. elegans. The concentrations of phenylethylamine, putrescine, cadaverine, histamine, and tyramine produced by the LAB were below the toxic limits of biogenic amines set by the European Food Safety Authority. Taken together, our results demonstrate that Weissella cibaria SCCB2306, P. acidilactici SDL1402, P. acidilactici SDL1405, and L. rhamnosus JDFM6 could be safe cholesterol-reducing probiotic candidates for preventing or managing hypercholesterolemia.

Abnormal adipocyte growth, distinguished by an increase in cell numbers and cellular differentiation, is regarded as a major pathological characteristic of obesity. Thus, inhibition of adipogenic differentiation in adipocytes could prevent obesity. Recently, certain probiotic stains have been reported to regulate lipid metabolism in vitro and/or in vivo. In this backdrop, this study aimed to investigate basic probiotic properties and potential antiobesity characteristics of mouse 3T3-L1 preadipocytes. Six lactic acid bacteria (LAB) strains were prescreened for their cholesterol-lowering activity, antioxidant activity, and survival at low pH and in a solution containing bile salts. These six strains were investigated for antiadipogenic activity by employing 3T3-L1 mouse preadipocytes. 3T3-L1 cells were treated with selected strains during the differentiation process. Lactobacillus johnsonii 3121 and Lactobacillus rhamnosus 86 were found to be more capable of reducing triglyceride and lipid accumulation, as compared to control group, which are fully differentiated 3T3-L1 adipocytes. These strains also inhibited adipocyte differentiation by downregulating the adipogenic transcription factor in 3T3-L1 adipocytes. Taken together, these results indicate that L. johnsonni 3121 and L. rhamnosus 86 could potentially act as probiotic bacteria and prevent fat accumulation by regulating adipogenesis-related markers.

Obesity is one of the major causes of the development of metabolic diseases, particularly cardiovascular diseases and type-2 diabetes mellitus. Increased lipid accumulation and abnormal adipocyte growth, which is an increase in cell numbers and differentiation, have been documented as major pathological characteristics of obesity. Thus, the inhibition of adipogenic differentiation prevents and suppresses obesity. Recently, specific probiotic strains have been known to regulate lipid metabolism in vitro and/or in vivo. Previously, we demonstrated that Lactobacillus johnsonni 3121 and Lactobacillus rhamnosus 86 could act as novel probiotic strains and reduce cholesterol levels. Moreover, both strains significantly reduced lipid accumulation and inhibited adipocyte differentiation by downregulating the adipogenic transcription factor in 3T3-L1 adipocytes. Therefore, L. johnsonni 3121 and L. rhamnosus 86 were selected for in vivo evaluation of their anti-obesity effects using a high-fat diet-induced obese mouse model. Daily oral administration of L. johnsonni 3121 and L. rhamnosus 86 for 12 weeks significantly improved serum lipid profile and downregulated the expression of genes related to adipogenesis and lipogenesis in epididymal white adipose tissue of high-fat diet fed obese mice (p

Skin wounds are an important clinical problem which affects millions of people worldwide. The search for new therapeutic approaches to improve wound healing is needed. The present study aimed to evaluate the effects of the oral treatment with the skin-related probiotics Lactobacillus johnsonii LA1 (LJ), L. paracasei ST11 (LP), and L. rhamnosus LPR (LR) in a model of excisional skin wounds in Swiss mice. The animals received daily oral gavage of PBS or 1 × 107 colony-forming units of LJ, LP, or LR, singly, beginning just after the creation of wounds until euthanasia. Blood flow was evaluated by laser Doppler perfusion imaging. Myeloperoxidase and N-acetyl-β-D-glucosaminidase activities were used to assess the accumulation of neutrophils and macrophages, respectively. The wound tissue was also collected for histological analyses (H&E, Toluidine blue, and Picrosirius red staining). The macroscopic wound closure rate was faster only in mice treated with LR, but not with LJ and LP, when compared to mice treated with PBS. Histological evaluations showed that treatment with LR stimulated wound epithelization when compared to PBS. Further analyses showed that wounds from LR-treated mice presented a significant decrease in macrophage (p

The influence of two autochthonous lactobacilli strains with probiotic potential (Lactobacillus mucosae CNPC007 and Lactobacillus plantarum CNPC020) in comparison to a commercially available probiotic strain (Lactobacillus rhamnosus LR32) in non-fermented dairy desserts added with ingredients (syrup and hydroethanolic extract) derived from jabuticaba (Myrciaria cauliflora) peels was investigated. L. mucosae showed the best survivability and stability of the studied lactobacilli after processing and during storage, respectively, and also remarkably influenced the texture and sensory features of desserts in comparison to the other strains; L. plantarum achieved viability comparable with the commercial probiotic, above 6 log cfu/g up to the 21st day of the products refrigerated storage. The hydroethanolic extract and syrup from the jabuticaba peel contributed to the phenolic content of the dairy desserts (around 30 mg GAE/100 g) that showed to be able to scavenge DPPH radicals (around 300 g dessert/g DPPH). The different lactobacilli strains did not significantly influence the antioxidant capacity parameters of the desserts (p > 0.05), although the desserts’ color was not stable during storage and tended to reduce the acceptability scores of the three trials. Non-fermented dairy desserts with jabuticaba peel ingredients showed to be good sources of phenolic compounds with an antioxidant capacity, offering suitable conditions for the viability maintenance of the autochthonous lactobacilli cultures.

Lactic acid bacteria (LAB) are important microorganisms for the food industry due to their functional activity, as starters and potential probiotic strains. With that in mind, we explored the LAB diversity in raw buffalo milk, screening for novel potential probiotic strains. A total of 11 strains were identified by combination of MALDI-TOF and partial 16S rDNA sequencing and selected as potential probiotic candidates. Bacteria innocuity assessment was performed by determining antimicrobial susceptibility and the presence of virulence factors. Antagonism activity against Escherichia coli, Pseudomonas aeruginosa, Listeria monocytogenes and Staphylococcus aureus was assessed, as well as milk proteolytic activity and exopolysaccharides production. Seven strains were identified as innocuous and two of them, Lactobacillus rhamnosus LB1.5 and Lactobacillus paracasei LB6.4 were selected for further probiotic potential analyses. Both strains demonstrated adhesion ability to Caco-2 cells, coaggregated with S. aureus and E. coli and maintained cell viability after gastrointestinal simulation in vitro, suggesting their probiotic potential. Furthermore, the transcriptional response of Lact. rhamnosus LB1.5 and Lact. paracasei LB6.4 to in vitro acid stress was assessed by RT-qPCR targeting seven genes related to adhesion, aggregation, stress tolerance, DNA repair and central metabolism. The association between the transcriptional responses and the maintenance of cell viability after gastrointestinal simulation highlights the genetic ability as probiotic of the two selected strains. Finally, we have concluded that Lact. rhamnosus LB1.5 and Lact. paracasei LB6.4 are important probiotic candidates to further in vivo studies.

In this placebo-controlled, double-blind clinical trial, we have investigated the effect of multi-strain probiotic (Bacillus coagulans Unique IS2, Lactobacillus rhamnosus UBLR58, Bifidobacterium lactis UBBLa70, Lactobacillus plantarum UBLP40 (each of 2 billion CFU); Bifidobacterium breve UBBr01, Bifidobacterium infantis UBBI01 (each of 1 billion CFU)) capsule with glutamine (250 mg) on students facing examination stress. A total of 80 students (18-24 years) were enrolled and randomised to receive multi-strain probiotic or placebo capsules twice a day for 28 days (i.e. pre- and during examination). The stress was analysed at the baseline and the end of the treatment by using the perceived stress scale (PSS), depression anxiety stress scale (DASS), and state-trait anxiety inventory (STAI) questionnaire. The serum cortisol levels were also determined. As a result, at the end of the trial, a total of 74 students completed the study, and those who consumed probiotic capsules showed a significant reduction in PSS, DASS, and STAI scores, and serum cortisol levels from the baseline as compared with placebo. No adverse events were reported during the study. In conclusion, the multi-strain probiotic is effective in reducing stress associated with examination. CTRI/2019/03/018178.

In this study, we aimed to characterize lactic acid bacteria strains derived from infants’ feces, to evaluate the probiotic potential and explore the wide-spectrum antimicrobial activity. Of 800 isolates, 20 inhibited the growth of enterotoxigenic Escherichia coli K88 and Salmonella enterica ATCC 13076. On the basis of 16S rRNA sequence analysis, the 20 isolates were assigned to Lactobacillus casei (7), Lactobacillus paracasei (2), Lactobacillus plantarum (4), Lactobacillus rhamnosus (2), Enterococcus avium (3), Enterococcus faecium (1), and Enterococcus lactis (1) species. In addition, 12 strains with high antimicrobial activity were investigated for the presence of probiotic properties such as physiological-biochemical characteristics, antimicrobial susceptibility, hemolytic activity, hydrophobicity, and aggregation activity. Wide-spectrum antimicrobial activity analysis revealed that approximately all tested strains inhibited the ten pathogens, and four strains (ZX221, ZX633, ZX3131, and ZX3875) had good probiotic properties and survived after being exposed to simulated gastrointestinal tract conditions. Moreover, we investigated the influence of pH on the wide-spectrum antimicrobial activity and found that four strains inhibited most pathogens at pH 4.5 and pH 5, whereas only ZX633 had an inhibitory effect on Bacillus subtilis ATCC 6633 and Micrococcus luteus ATCC 4698 at pH 5.5. Overall, Lact. casei ZX633 had wide-spectrum antimicrobial activity and could be considered a potential probiotic.

In the current study, we investigated the effect of a probiotic bacterium (Lactobacillus rhamnosus ATCC 7469) microencapsulated with alginate and hi-maize starch and coated with chitosan on improving growth factors, body composition, blood chemistry, and the immune response of rainbow trout (initial weight: 18.41 ± 0.32 g). Four experimental diets were formulated to feed fish for 60 days. They were control diet without any additive (C), diet added with beads without probiotic (E), a probiotic sprayed to the diet (L.r), and encapsulated probiotic supplemented diet (E-L.r). The results indicated that feeding with E-Lr significantly improved weight gain (84.98 g) and feed conversion ratio (0.95) compared to the other groups (P

Probiotic as a preventive medicine is emerging as an indispensable tool in addressing the foodborne infections or gastrointestinal disorders. The present study was sought to determine the in vitro prophylactic potential of probiotic Lactobacillus rhamnosus (LR: MTCC-5897) against Escherichia coli (ATCC 14948) induced impairment in intestinal barrier function using Caco-2 cells. Intestinal cells exposed to E. coli demonstrated significantly higher phenol red flux (p < 0.05) and concomitantly decreased TEER (0.69 ± 0.01) in contrast to control or L. rhamnosus (109 cfu/mL)-treated cells. However, E. coli-induced barrier hyperpermeability was restored to significant extents (p < 0.01) when E. coli were excluded, competed or displaced by probiotic LR. Similarly, exposure of Caco-2 cells to E. coli reduced the mRNA expression of key tight junction genes, viz. Zo-1, Claudin-1, Occludin and Cingulin which however were restored significantly (p < 0.05) with L. rhamnosus treatment during exclusion or competition than displacement assays. The protective behaviour of probiotic LR against E. coli can also be observed in immunofluorescent and electron micrograph where intact cellular morphology along with preserved distribution and localisation of key integrity proteins can be found in LR-treated cells in contrast to distorted and disorganised distribution observed with E. coli exposure. In conclusion, L. rhamnosus inhibited and re-established E. coli-impaired intestinal barrier function by improving the expression and distribution of key junction protein and hence could serve an essential food additive to address the various health complications especially those associated with gastrointestinal tract.

Growth media composition is a critical factor influencing the yield of bacterial exopolysaccharides (EPSs), which have attracted the interest of researchers around the world due to their diverse physicochemical and biological properties. This work presents the optimization of media for EPS synthesis by three Lactobacillus rhamnosus strains, namely ŁOCK 0943, ŁOCK 0935, and OM-1. The optimized media led to a more than 13-fold increase in EPS yield for L. rhamnosus ŁOCK 0943 (from 85 to 1138.2 mg/L), an almost 9-fold increase for L. rhamnosus ŁOCK 0935 (from 103.67 to 900 mg/L), and a more than 7-fold increase for L. rhamnosus OM-1 (from 133.67 to 987.84 mg/L) as compared to cultures in standard MRS medium (de Man, Rogosa, and Sharpe). It has been found that the main medium-related determinant of EPS synthesis by the studied L. rhamnosus strains are the carbon source—in this case, it was fructose and sucrose.

This study examined whether Lactobacillus rhamnosus GG (LGG) and Bifidobacterium bifidum TMC3115 (TMC3115) could morphologically or physiologically influence hippocampal neuronal development in vitro. Hippocampal neurons cultured in vitro were exposed to live or heat-inactivated LGG or TMC3115 for either 6 or 24 h. Neuronal morphological changes and drebrin (DRB) and synaptophysin (SYP) protein levels were monitored using immunofluorescence. And the levels of DRB, SYP, and brain-derived neurotrophic factor (BDNF), and cAMP-response element binding protein (CREB) mRNA were detected using RT-PCR. The BDNF, CREB, and phosphorylated-CREB (P-CREB) protein levels were detected by extraction-enzyme-linked immunosorbent assay (ELISA) or Western blot assays. Heat-inactivated LGG and TMC3115 could enhance neuron viability, DRB and SYP protein levels, and BDNF mRNA level were significantly altered after exposure to the tested bacteria with 6 h or 24 h. There were no significant differences in neuronal morphology or DRB, SYP, or CREB mRNA levels among the groups following bacterial exposure. However, following exposure of live TMC3115 for 24 h, the neuronal BDNF and P-CREB protein levels were both significantly up-regulated as detected by western blot assays. These results demonstrated that LGG and TMC3115 could affect neuronal viability, along with hippocampal synaptic and functional development, in a strain-dependent manner, which may also be closely associated with the physiological and culture conditions of each strain. Up-regulated P-CREB may be one of the underlying mechanisms by which the bacteria, especially neurons following exposure of live TMC3115 for 24 h, are able to regulate neuronal BDNF protein production.

According to FAO and WHO, probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Most probiotic bacteria used today belong to the genera Lactobacillus and Bifidobacterium and are of animal or human origin. The fundamental characteristic routinely evaluated in potential probiotics strains is their limited viability loss during gastrointestinal transit (GIT), but to date, no studies reported whether probiotics, besides viability, still also maintain their beneficial properties intact. To study this aspect, we considered two strains, Lactobacillus rhamnosus DTA 79 and L. paracasei DTA 83, previously characterised for the presence of some probiotic properties, isolated from faeces of 7- to 21-day-old babies. Here, we examined some additional properties, namely antibiotic resistance, resistance to lysozyme, presence of haemolytic activity and inhibition of pathogen biofilm formation. We then tested the effect of in vitro GIT on all these features and our results show evidence that this procedure had in some cases limited and in others no significant effects on them. Additionally, we examined the gastrointestinal resistance of the strains after skim milk fermentation and successive storage of the product for 20 and 40 days at refrigeration temperature, to see whether prolonged storage could weaken cell resistance to GIT. Our results demonstrate that a protracted refrigeration period before in vitro GIT did not affect or influenced very weakly this essential probiotic property.

Silver nanoparticles are the most desirable nanoparticles broadly used in diverse fields. This study intends to investigate the anticancer properties of synthesized silver/Lactobacillus rhamnosus GG nanoparticles (Ag-LNPs) as a reducing and stabilizing agent in the synthesis process. To prepare silver/Lactobacillus rhamnosus GG nanoparticles, 1 mg/ml cell lysate of Lactobacillus rhamnosus GG and 1 mM silver nitrate solution were mixed and incubated for 72 h. XRD, FTIR, and TEM methods were used for nanoparticle characterization. MTT assay and annexin/PI staining were employed to analyze the toxicity and apoptotic cells levels of Ag-LNPs, respectively. TEM showed that these nanoparticles are spherical shaped about 233 nm in size. FTIR spectroscopy demonstrated that Ag-LNPs were functionalized with biomolecules. XRD pattern showed high purity and face-centered crystal structure of Ag-LNPs. MTT assay revealed that the percentages of HT-29 live cells significantly reduced in the high concentration of Ag-LNPs. Annexin/PI staining showed that these nanoparticles could lead HT-29 cells to apoptosis. This study showed the new Ag-LNP-synthesizing method using Lactobacillus rhamnosus GG as a cost-effective and efficient approach. Also, it showed that these nanoparticles can be considered as a potential active agent for biomedical applications and drug delivery due to their anticancer activities.

Lactobacillus paracasei SD1, Lactobacillus rhamnosus SD11, and Lactobacillus gasseri SD12 were proposed as potential probiotics for oral health. However, the effects of them on host physiology are still unknown. This study aimed to select strains that can promote host growth and development in monocolonized Drosophila model compared with axenic and the commercial Lactobacillus rhamnosus GG–treated flies. The morphogenesis and growth of axenic Drosophila melanogaster were assessed from embryo to adult stage when provided with each probiotic strain–supplemented food. The colonization and persistence of probiotic in fly gut were also evaluated. The results indicated that axenic condition caused the lowest adult weight and emergence rate. All probiotic groups had higher weight than axenic group. Lact. rhamnosus SD11 group presented high adult emergence rate equivalent to Lact. rhamnosus GG group, which is significantly higher than the others. However, Lact. gasseri SD12 group had significantly lower adult weight and emergence rate when compared with Lact. rhamnosus GG group. The gut probiotics levels were rapidly increased within the first day after receiving probiotics. After probiotic cessation, their number in gut decreased and was maintained at low level, except for Lact. gasseri SD12, which completely vanished since day one. In conclusion, Lact. paracasei SD1, Lact. rhamnosus SD11, and Lact. rhamnosus GG can affect morphogenesis and weight of flies when fed since immature stage and have short period gut colonization. The findings of this study could possibly imply comparable health-promoting effects between Lact. paracasei SD1 and Lact. rhamnosus SD11 to commercial strain in Drosophila model.

Tibial dyschondroplasia (TD) is a leg disorder caused by the abnormal development of the tibia in fast-growing poultry. Lactobacillus rhamnosus (L. rhamnosus) strains have been reported to have effects on increasing bone growth and improving osteoporosis in animals. However, whether L. rhamnosus JYLR-005 can improve bone growth in TD chickens remains unclear. In this study, we noted that L. rhamnosus JYLR-005 could not reduce the suppression of the production performance of TD broilers (p > 0.05) but had a slight protective effect on the broiler survival rate (χ2 = 5.571, p = 0.062). However, for thiram-induced TD broiler chickens, L. rhamnosus JYLR-005 could promote tibia growth by increasing tibia-related parameters, including the tibia weight (day 11, p = 0.040), tibia length (day 15, p = 0.013), and tibia mean diameter (day 15, p = 0.035). Moreover, L. rhamnosus JYLR-005 supplementation improved the normal growth and development of the tibial growth plate by maintaining the morphological structure of the chondrocytes and restored the balance of calcium and phosphorus. Taken together, these findings provide a proof of principle that L. rhamnosus JYLR-005 may represent a therapeutic strategy to treat leg disease in chickens.

Several species of eukaryotic organisms living in the high mountain areas of Armenia with naturally occurring levels of radiation have high adaptive responses to radiation. We speculate on the role of the gastrointestinal microbiota in this protection against radiation. Therefore, seventeen microorganisms with high antagonistic activities against several multi-drug-resistant pathogens were isolated from the human and animal gut microbiota, as well as from traditional Armenian fermented products. These strains were tested in vivo on Wistar rats to determine their ability to protect the eukaryotic host against radiation damages. The efficiency of the probiotics' application and the dependence on pre- and post-radiation nutrition of rats were described. The effects of Lactobacillus rhamnosus Vahe, isolated from a healthy breastfed infant, and Lactobacillus delbrueckii IAHAHI, isolated from the fermented dairy product matsuni, on the survival of irradiated rats, and their blood leucocyte and glucose levels, were considered to be the most promising, based on this study's results.

The antioxidant activities and probiotic properties of lactic acid bacteria (LAB) selected from traditional artisanal milk cheese from Northeast China were investigated in this study. Among the 322 isolates, 175 LAB were identified through probiotic characterizations. Twenty-three out of the 175 strains exhibited antibacterial activity against more than four enteropathogenic bacteria. The antioxidant action of 23 LAB was evaluated by different methods, including scavenging of hydroxide radicals, DPPH radicals, superoxide anions, and ABTS+ radical cation. The ability to resist hydrogen peroxide and superoxide dismutase activity was also studied. These strains significantly showed antioxidative capacity compared with a non-antioxidative strain, closely followed by the standard probiotic strain Lactobacillus rhamnosus GG or even better. Based on 16S ribosomal RNA-sequence analysis, the 23 isolates belonged to the species Lactobacillus plantarum (16), Lactobacillus paracasei (2), Enterococcus faecium (2), Lactobacillus helveticus (1), Weissella paramesenteroides (1), and Pediococcus pentosaceus (1). In addition, five out of the 23 strains were susceptible to most of the tested antibiotics, showed extremely high levels of hydrophobicity similar to or better than the reference strain L. rhamnosus GG, and did not exhibit any hemolytic activity. These five strains were also confirmed safe through bacterial translocation. Results suggest that at least five probiotic candidates can be explored as prospective antioxidants and used as a potential antioxidant strain to be utilized in the development of functional foods and new starter cultures.

The present study shows that, from 300 Lactobacillus strains isolated from the oral cavity and large intestine of 600 healthy people, only 9 had high antagonistic activity against pathogens and opportunistic pathogens. All antagonistic strains of lactobacilli have been identified by 16S rRNA sequencing and assigned to four species: Lactobacillus fermentum, Lactobacillus rhamnosus, Lactobacillus plantarum, and Lactobacillus casei. In addition, these lactobacilli appeared to be nonpathogenic and had some probiotic potential: the strains produced lactic acid and bacteriocins, showed high sensitivity to broad-spectrum antibiotics, and were capable of forming biofilms in vitro. With the help of PCR and specific primers, the presence of genes for prebacteriocins in L. plantarum (plnEF, plnJ, plnN) and L. rhamnosus (LGG_02380 and LGG_02400) has been revealed. It was found that intestinal strains of lactobacilli were resistant to hydrochloric acid and bile. Lactobacilli isolated from the oral cavity were characterized by a high degree of adhesion, whereas intestinal strains were characterized by average adhesion. Both types of lactobacilli had medium to high rates of auto-aggregation and hydrophobicity and could coaggregate with pathogens and opportunistic pathogens. Additionally, the ability of the lactobacilli strains to produce gasotransmitters, CH4, CO2, C2H6, CO, and NH3, has been revealed.

The present study was to investigate the utilization of prebiotics by Lactobacillus rhamnosus NCDC 298 and its synergistic adversary effect on both population and production of heat-labile (LT) toxin in enterotoxigenic Escherichia coli (ETEC). To select suitable prebiotic in order to enhance functionality, its utilization and the prebiotic activity score was examined. Antivirulence effect on ETEC was inspected by its inactivation rate and heat-labile toxin production in presence of different synbiotic combination. L. rhamnosus NCDC 298 strain grown well on media supplemented with fructooligosaccharides (FOS) and galactooligosaccharides (GOS), whereas significant inactivation of ETEC was observed when FOS was added to the co-culture medium. Significant decrease in LT enterotoxin was seen through GM1 ganglioside enzyme linked immunoassay (GM1 ELISA), when ETEC has grown with L. rhamnosus NCDC 298 and FOS. Short-chain FOS proved to be the most effective substrate, improving antagonistic activity for L. rhamnosus NCDC 298. Both L. rhamnosus NCDC 298 with FOS can be used as an effective synbiotic combination for secretory antidiarrheal fermented dairy formulations.

Human feces were streaked onto MRS Agar adjusted to pH 2.5, 3.0, and 6.4, respectively, and medium supplemented with 1.0% (w/v) bile salts. Two aciduric strains, identified as Lactobacillus reuteri HFI-LD5 and Lactobacillus rhamnosus HFI-K2 (based on 16S rDNA and recA sequences), were non-hemolytic and did not hydrolyze mucin. The surface of Lactobacillus reuteri HFI-LD5 cells has a weak negative charge, whereas Lactobacillus rhamnosus HFI-K2 has acidic and basic properties, and produces exopolysaccharides (EPS). None of the strains produce bacteriocins. Both strains are resistant to several antibiotics, including sulfamethoxazole-trimethoprim and sulphonamides. The ability of Lactobacillus reuteri HFI-LD5 and Lactobacillus rhamnosus HFI-K2 to grow at pH 2.5 suggests that they will survive passage through the stomach. EPS production may assist in binding to intestinal mucus, especially in the small intestinal tract, protect epithelial cells, and stimulate the immune system. Lactobacillus reuteri HFI-LD5 and Lactobacillus rhamnosus HFI-K2 may be used as probiotics, especially in the treatment of small intestinal bacterial overgrowth (SIBO).

Diarrhea is considered as an important cause of morbidity and mortality, even though one of the main reasons of death following diarrhea is initiated by dysentery. In recent years, the consumption of probiotics has been proposed for the treatment of infectious diarrhea. Despite most of the studies on probiotics have focused on acute watery diarrhea, few studies in the field of dysentery have found beneficial effects of probiotics. This study is a randomized double-blind clinical trial. The patients were randomly placed into control and case groups. In the intervention group, the patients received probiotics in the form of Kidilact® sachet, which contained high amounts of 7-strain friendly bacteria strains of Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium infantis, Bifidobacterium breve, and Streptococcus thermophiles. On the other hand, the patients in the control group received placebo sachets on a daily basis for 5 days. It is notable that the treatment protocol of acute dysentery was done on both groups. The results of this study showed significant differences in the duration of blood in diarrhea between probiotic consumers (2.62 days) and the control group (3.16 days) (P value = 0.05). Additionally, significant differences in the average length of hospitalization in probiotic consumers (3.16 days) and control (3.66 days), (P value = 0.02) could be claimed that the consumption of probiotics is effective in reducing the duration of dysentery and diarrhea. The results of this study suggest that the use of probiotics can be effective in reducing the duration of blood in diarrhea. This study was also recorded in the Iran center of clinical trials registration database (IRCT2014060617985N1).

Multidrug resistance (MDR) is a serious health threat throughout the world resulting in reduced efficacy of antibacterial, antiparasitic, antiviral, and antifungal drugs. One of the most promising concepts that may represent a good alternative to antibiotics can be the use of bacteriocins obtained from lactic acid bacteria. The L. rhamnosus BTK 20-12 strain was isolated from traditional Armenian naturally fermented salted cheese. The probiotic potential of the strain was approved. It was shown that strain produced at less two bacteriocins (BCN 1 and BCN 2) with different molecular weight (1427 Da and 602.6 Da, respectively). Bacteriocins inhibited the growth of multidrug-resistant bacteria of different etiologies and belong to different taxonomic groups with diverse efficiency and it depends on properties of bacteriocins, as well as from isolation sources of pathogens. Thus, bacteriocins of L. rhamnosus BTK 20-12 have protein-like nature and a broad range of activity and are excellent candidates for the development of new prophylactic and therapeutic substances to complement or replace conventional antibiotics.

This investigation has been performed to show the efficacy of Lactobacillus rhamnosus GG (LGG) together with milk-free diet in patients with cow’s milk protein allergy (CMPA). This multicentre prospective investigation has been performed in 0–12 months of age children diagnosed as CMPA clinically and biochemically. Patients have been randomly divided in to two groups. Infants in probiotic group were received with cow’s milk protein free diet and per oral (p.o.) daily 1X109 CFU LGG and in placebo group with milk-free diet and placebo. Mothers of all breast-fed patients have been put on milk-free diet and all patients fed with formula, offered to extensively hydrolysed formula. Symptoms like diarrhoea, vomiting, mucousy or bloody stool, abdominal pain or distension, constipation, dermatitis and restiveness were recorded at the beginning and weekly during the receiving dietary by the investigator. One-hundred infants diagnosed CMPA were included in this double-blind placebo controlled study. Forty-eight infants placed in probiotic group and 52 in placebo group. After 4 weeks of receiving dietary, infants in probiotic group have showed statistically significant improvement in symptoms of bloody stool, diarrhoea, restiveness and abdominal distension (p ≤ 0.001). Whilst statistically significant improvement was also observed in symptoms of mucousy stool (p = 0.038) and vomiting (p = 0.034), no significant improvement were observed in abdominal pain (p = 0.325), constipation (p = 0.917) and dermatitis (p = 0.071). In this study we observed significant improvement in symptoms of infants diagnosed CMPA receiving dietary LGG with cow’s milk-free diet.

The present study was designed to envisage the antigiardial efficacy of killed probiotic and probiotic protein (PP) of Lactobacillus rhamnosus GG in murine giardiasis. Experimentally, it was observed that animal administered either with probiotic protein emulsified with adjuvant (PP(E) + Giardia) or killed probiotic (killed probiotic (i/p) + Giardia) had significantly reduced Giardia cycle with respect to observed severity and duration of giardiasis compared with Giardia-infected mice. Further, it was found that animals belonging to PP(E) + Giardia and killed probiotic (i/p) + Giardia had significantly high levels of antigiardial IgA antibody and nitric oxide both in serum and in intestinal fluid compared with Giardia-infected and counter control mice. Histopathologyically, also animals belonging to PP(E) + Giardia and killed probiotic (i/p) + Giardia animals had intact mucosal epithelium lining, basal crypts, and normal villi along with increased goblet cells compared with severe microvillus atrophy, vacuolated epithelial cells, and ileitis in Giardia-infected mice. This is the first-ever study to demonstrate that prior administration of either killed probiotics or probiotic protein of effective probiotic reduced both the severity and the duration of giardiasis mainly by modulating the gut microbiome and morphology along with mucosal immunity, but animals belonging to PP(E) + Giardia had better response than killed probiotic (i/p) + Giardia suggesting that probiotic components do have adjuvant potential and may be used as the vaccine candidate for gastrointestinal diseases.

Lactobacillus rhamnosus GG (L. rhamnosus GG) cells were encapsulated in buttermilk proteins by spray drying, alone (E), or with Agave tequilana fructans (CEF). Buttermilk proteins acted as a thermo-protector for the probiotic cells undergoing the spray-dried process. The addition of Agave fructans in CEF microcapsules significantly enhanced storage stability and survival to in vitro simulated gastrointestinal conditions, compared to E capsules. After 14 days storage at − 20 °C, the number of living cells in CEF microcapsules was in the order of 7.7 log CFU • mL−1 and the survivability in simulated gastrointestinal environment was 73.23%. Spray-dried microparticles were cultured in goat milk to study biomass production. Agave fructans offered a favorable microenvironment and better growth substrate. The population of CEF viable cells reached 1.08 ± 0.02 × 1010 CFU • mL−1 after 18 h of fermentation. In contrast, the population of E viable cells were 3.0 ± 0.01 × 109 CFU • mL−1. The generation time of CEF, L. rhamnosus GG was 15% faster than E, L. rhamnosus GG. Encapsulation with buttermilk proteins in the presence of Agave fructans by spray drying could be suitable for preservation of probiotic powders and may be for a more effective application of probiotics in goat dairy products.

In this study, we report on the formation and resilience of Lactobacillus reuteri HFI-LD5 and Lactobacillus rhamnosus HFI-K2 biofilms cultivated in a CO2 evolution measurement system (CEMS) and exposed to biologically relevant, fasting-state gastrointestinal fluids under continuous flow conditions. For comparative purposes, planktonic and sessile populations of L. reuteri HFI-LD5 and L. rhamnosus HFI-K2 were each exposed to fasting-state gastric fluid (FSGF, pH 2.0) for 2 h, fasting-state intestinal fluid (FSIF, pH 7.5) for 6 h, and simulated colonic fluid (SCoF, pH 7.0) for 24 h. Planktonic cell numbers of L. reuteri HFI-LD5 declined from 6.6 log10 CFU/mL to 3.2 log10 CFU/mL and L. rhamnosus HFI-K2 from 6.6 log10 CFU/mL to undetectable levels after exposure to FSGF. Limited loss in viability was observed when free-floating cells were exposed to FSIF and SCoF. Sessile populations of both strains survived and recovered from the sequential exposure to all three gastric fluids despite observed detachment of biofilm biomass and a temporary decrease in metabolic activity to below detection limits, as recorded by changes in whole-biofilm CO2 production rates. The planktonic cell-focused gut microbiome-related research has most likely caused an underestimation in the overall survival ability of microorganisms in the gastrointestinal tract. Sessile cells of L. reuteri HFI-LD5 were metabolically inactive when exposed to gastric (FSGF) and intestinal (FSIF) fluids, suggesting that biofilms are formed in the small intestinal tract as survival mechanism. In the case of L. rhamnosus HFI-K2, cells were released from biofilms when suddenly exposed to pH 2.0.

Probiotic-rich foods are consumed without much restriction. We report here, a case of septic shock caused by yogurt derived Lactobacillus species in a 54-year-old male patient with acute promyelocytic leukemia, in second complete remission, and who was an autologous stem cell transplantation recipient. He received high dose chemotherapy and autologous peripheral blood stem cell transplantation. He ingested commercially available probiotic-enriched yogurt because of severe diarrhea. One week later, he developed septic shock, and the pathogen was determined by strain-specific PCR analysis as Lactobacillus rhamnosus GG (ATCC 53103), which was found to be identical with the strain in the yogurt he consumed. Thus, because even low virulent Lactobacilli in the probiotic products can be pathogenic in the compromised hosts, ingestion of such products should be considered with caution in neutropenic patients with severe diarrhea, such as stem cell transplantation recipients.

This study aimed to investigate the probiotic potential of lactic acid bacteria (LAB) strains isolated from De'ang pickled tea, a traditional food consumed by the De'ang nationality of Yunnan, China. Twenty-six LAB strains isolated from De'ang pickled tea were subjected to identification based on 16S rRNA gene sequence analysis. Twenty-four belonged to Lactobacillus plantarum, one belonged to Enterococcus casseliflavus, and one belonged to Lactobacillus acidophilus. Eighteen out of 26 LAB strains which showed a higher capability to tolerate simulated gastrointestinal juices were chosen to further evaluate their probiotic properties. Varied adhesive abilities and auto-aggregative capacities of selected LAB strains were dependent on species and even strains. All tested LAB strains were resistant to kanamycin, streptomycin, gentamycin, and vancomycin and sensitive to tetracycline and chloramphenicol. Ten out of the 18 strains are resistant to ampicillin, and the remaining strains are sensitive to ampicillin; 4 out of the 18 strains showed resistance to erythromycin. Compared to reference strain Lactobacillus rhamnosus strain GG, these LAB strains had a greater or comparative antimicrobial activity against Salmonella typhimurium or Escherichia coli. In contrast, eight out of the 18 strains suppressed growth of Shigella flexneri. Two L. plantarum strains, ST and STDA10, not only exhibited good probiotic properties but also showed a good ability of scavenging DPPH and ABTS+. This study suggests that L. plantarum ST and STDA10 could be used as potential probiotics applied in functional foods.

The high rate of vaginal Candida albicans recurrence is attributed to azole resistance rates as high as 15 %. The aim of this study was to determine the clinical and microbiological efficacy of standard azole therapy for treatment of vaginal C. albicans infection alone and in combination with local probiotic as well as the effects on vaginal microbiota. This study included 436 women with vaginal candidiasis randomly assigned to two treatment groups. The first group, with 207 patients (12 dropouts), was administered 150 mg fluconazole and a single vaginal globule of fenticonazole (600 mg) on the same day. The second group of 209 patients (8 dropouts) followed the same treatment schedule; however, ten applications of a vaginal probiotic containing Lactobacillus acidophilus, L. rhamnosus, Streptococcus thermophilus, and L. delbrueckii subsp. bulgaricus were also administered beginning the fifth day after azole treatment. Microbiological analysis of the therapy efficacy in the first treatment group showed C. albicans resistance in over 30 % of patients. Clinical complaints persisted after treatment administration in 79.7 % (n = 165) of women in this group. Clinical complaints in the second group decreased to 31.1 % (n = 65) and microbiological efficacy also improved among investigated parameters, from 93.7 % (n = 193) to 95.2 % (n = 198). The local application of probiotics after administration of combined azoles for treatment of vaginal C. albicans infections increases therapy efficacy and could prevent relapse.

The present study is utilizing the targeted therapeutic approach and antioxidant potential of selected probiotic biomass in mitigating toxic side effects of chemotherapeutic agents. Multicomponent carrier system consisting of 5-fluorouracil (5-FU) and selected probiotic strain with higher free radical scavenging activity was prepared using spray drying technique. Prepared spray dried microparticles were characterized for various physical, pharmaceutical, and biopharmaceutical properties including particle size, moisture content, entrapment efficiency, in vitro drug release, DSC, XRD, cell uptake, histopathology, and pharmacokinetic studies. In addition to the above, optimized formulation was subjected to in vivo targeting efficacy studies using radiographic technique. Optimized formulation meets the necessary physical requirement for pharmaceutical powder. X-ray studies revealed that the prepared spray dried formulations are able to target the colon. Pharmacokinetic endpoints with an extended t 1/2 and lower C max indicate lower systemic toxicity. Intact nature of colonic epithelium in experimental formulation clearly demonstrates the protective role of Lactobacillus rhamnosus in minimizing the harmful consequence induced by 5-FU. Existing outcomes provide the basis for a combination of targeted therapeutic approach with natural antioxidant capacity of potential probiotic strain which could help to mitigate the problems associated with traditional chemotherapy.

While the number of scientific publications related to health-promoting bacteria and antimicrobials of proteinaceous nature is growing, there is an obvious need for a better comprehension of what these studies actually provide the community and which directions these studies should be taking. With no intention of neglecting fundamental science (in which true knowledge helps separate fact from fiction, and eventually finds its practicality), I would still like to step on a dangerous path and speculate on the near-future progress in the aforementioned field of science with emphasis on possible beneficial outcomes. The number of marketed food products and dietary supplements labeled as ‘‘probiotics’’ or ‘‘containing probiotic bacteria’’ is virtually incalculable. In 2010, the global probiotic market was estimated at $22.6 billion and is projected to reach $28.8 billion by 2015 [1]. Very few microorganisms have been subjected to thorough in vitro studies confirming their specific health-promoting activity, and even fewer were subsequently subjected to and passed the appropriate human trials. A few studies of interest include those which investigated the strains Lactobacillus plantarum 299v, Lactobacillus casei Shirota, Lactobacillus rhamnosus GG should probably be mentioned—yet even the latter was reported on several occasions as associated with bacterial sepsis (for review see: [2]). Additionally, probiotics can be truly dangerous, posing as a wolf in the sheep’s clothing: They have been linked to an increase in mortality rate if administered to severely immunocompromised patients [3]. Those interested in ‘‘legal’’ probiotics may consider looking at the list of so-called ‘‘Commercial Strains Sold As Probiotics’’ [4] where the phrase ‘‘sold as’’ is perhaps the most telling in indicating the less that firm certainty about these strains being large-scale human trialproven as delivering measurable benefits. Still, there is WHO guidance on probiotics [5] and a brief overview of the claims discussed as required and sufficient for placing a microorganism into a group of ‘‘good fellows’’ [6]. Finally, NIH Grant 5R01HG005171-02 resulted in a document entitled ‘‘Federal Regulation of Probiotics: An Analysis of the Existing Regulatory Framework and Recommendations for Alternative Frameworks’’ [7] which only confirms the murky reality of less than stringent and frequently disconnected regulations currently being observed. As of December 14, 2012, the European Food Safety Authority (EFSA) posed serious and soundly justified [8] restrictions on labeling food products containing probiotics—the matter was strongly opposed by the major world manufacturers of microorganism-fermented/containing food products and by the large-scale manufacturers of microbial cultures [9]. Currently, there are two (European and North American) different statuses resulting in two different approaches addressing the real problem: how to separate the truly beneficial microorganisms from the crowd of overall harmless but ‘‘indifferent’’ bugs broadly used to make some products attractive to the consumers [10]. All of these leave a few questions and hopefully some answers. The diversity and multiplicity of the human microbiota cannot be ignored. While broad generalizations can be made concerning the frequency of certain species in our body’s ecological niches, they are genetically variable [11]. Certainly, the common strains associated with healthy human subjects should do no harm when ingested with a food product or administered otherwise. The additional health benefits are somewhat doubtful; why should they deliver anything in addition to what they already provide? M. L. Chikindas (&) School of Environmental and Biological Sciences, Rutgers State University, New Brunswick, NJ 08901, USA e-mail: tchikindas@AESOP.Rutgers.edu

Estimation of bile tolerance, endurance to gastric and intestinal environment and adhesion potential to intestinal cells are significant selection criteria for probiotic lactic acid bacteria (LAB). In this paper, the probiotic potential of native bacteriocin-producing LAB isolated previously from indigenous source has been determined through quantitative approaches. Among fifteen anti-listerial bacteriocin-producing native LAB, ten strains were found to be bile tolerant. The presence of bile salt hydrolase (bsh) gene in native Lactobacillus plantarum strains was detected by PCR and confirmed by nucleic acid sequencing of a representative amplicon. Interestingly, three native LAB strains exhibited significant viability in simulated gastric fluid, analogous to the standard LAB Lactobacillus rhamnosus GG, while an overwhelming majority of the native LAB strains demonstrated the ability to survive and remain viable in simulated intestinal fluid. Quantitative adhesion assays based on conventional plating method and a fluorescence-based method revealed that the LAB isolates obtained from dried fish displayed significant in vitro adhesion potential to human adenocarcinoma HT-29 cells, and the adhesion level was comparable to some of the standard probiotic LAB strains. The present study unravels putative probiotic attributes in certain bacteriocin-producing LAB strains of non-human origin, which on further in vivo characterization could find specific applications in probiotic food formulations targeted for health benefits.

The effect of two putative probiotic strains, Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74, on the control of cholesterol efflux in enterocytes was assessed by focusing on the promotion of ATP-binding cassette sub-family G members 5 and 8 (ABCG5 and ABCG8). Differentiated Caco-2 enterocytes were treated with live bacteria, heat-killed bacteria, a bacterial cell wall fraction, and metabolites and were subjected to cholesterol uptake assay, mRNA analysis, and protein analyses. Following LXR-transfection by incubation with CHO-K1 cells in DNA-lipofectin added media, the luciferase assay was conducted for LXR analysis. Treatment of Caco-2 cells with L. rhamnosus BFE5264 (isolated from traditional fermented Maasai milk) and L. plantarum NR74 (isolated from Korean kimchi) resulted in the up-regulation of LXR, concomitantly with the elevated expression of ABCG5 and ABCG8. This was associated with the promotion of cholesterol efflux at significantly higher levels compared to the positive control strain L. rhamnosus GG (LGG). The experiment with CHO-K1 cells confirmed up-regulation of LXR-beta by the test strains, and treatment with the live L. rhamnosus BFE5264 and L. plantarum NR74 strains significantly increased cholesterol efflux. Heat-killed cells and cell wall fractions of both LAB strains induced the upregulation of ABCG5/8 through LXR activation. By contrast, LAB metabolites did not show any effect on ABCG5/8 and LXR expression. Data from this study suggest that LAB strains, such as L. rhamnosus BFE5264 and L. plantarum NR74, may promote cholesterol efflux in enterocytes, and thus potentially contribute to the prevention of hypercholesterolemia and atherosclerosis.

Although the detection of viable probiotic bacteria following their ingestion and passage through the gastrointestinal tract (GIT) has been well documented, their mucosal attachment in vivo is more difficult to assess. In this study, we investigated the survival and mucosal attachment of multi-strain probiotics transiting the rat GIT. Rats were administered a commercial mixture of the intestinal probiotics Lactobacillus acidophilus LA742, Lactobacillus rhamnosus L2H and Bifidobacterium lactis HN019 and the oral probiotic Streptococcus salivarius K12 every 12 h for 3 days. Intestinal contents, mucus and faeces were tested 6 h, 3 days and 7 days after the last dose by strain-specific enumeration on selective media and by denaturing gradient gel electrophoresis. At 6 h, viable cells and DNA corresponding to all four probiotics were detected in the faeces and in both the lumen contents and mucus layers of the ileum and colon. Viable probiotic cells of B. lactis and L. rhamnosus were detected for 7 days and L. acidophilus for 3 days after the last dose. B. lactis and L. rhamnosus persisted in the ileal mucus and colon contents, whereas the retention of L. acidophilus appeared to be relatively higher in colonic mucus. No viable cells of S. salivarius K12 were detected in any of the samples at either day 3 or 7. The study demonstrates that probiotic strains of intestinal origin but not of oral origin exhibit temporary colonisation of the rat GIT and that these strains may have differing relative affinities for colonic and ileal mucosa.