BackgroundGut lactobacilli can affect the metabolic functions of healthy humans. We tested whether a 1500 kcal/d diet supplemented with cheese containing the probiotic Lactobacillus plantarum TENSIA (Deutsche Sammlung für Mikroorganismen, DSM 21380) could reduce some symptoms of metabolic syndrome in Russian adults with obesity and hypertension.MethodsIn this 3-week, randomized, double-blind, placebo-controlled, parallel pilot study, 25 subjects ingested probiotic cheese and 15 ingested control cheese. Fifty grams of each cheese provided 175 kcal of energy. Blood pressure (BP), anthropometric characteristics, markers of liver and kidney function, metabolic indices (plasma glucose, lipids, and cholesterol), and urine polyamines were measured. Counts of fecal lactobacilli and L. plantarum TENSIA were evaluated using molecular methods. The data were analyzed by t-test for independent samples and Spearman’s partial correlation analysis.ResultsThe probiotic L. plantarum TENSIA was present in variable amounts (529.6 ± 232.5 gene copies) in 16/25 (64%) study subjects. Body mass index (BMI) was significantly reduced (p = 0.031) in the probiotic cheese group versus the control cheese group. The changes in BMI were closely associated with the water content of the body (r = 0.570, p = 0.0007) when adjusted for sex and age. Higher values of intestinal lactobacilli after probiotic cheese consumption were associated with higher BMI (r = 0.383, p = 0.0305) and urinary putrescine content (r = 0.475, p = 0.006). In patients simultaneously treated with BP-lowering drugs, similar reductions of BP were observed in both groups. A positive association was detected between TENSIA colonization and the extent of change of morning diastolic BP (r = 0.617, p = 0.0248) and a trend toward lower values of morning systolic BP (r = −0.527, p = 0.0640) at the end of the study after adjusting for BMI, age, and sex.ConclusionIn a pilot study of obese hypertensive patients, a hypocaloric diet supplemented with a probiotic cheese helps to reduce BMI and arterial BP values, recognized symptoms of metabolic syndrome.Trial registrationCurrent Controlled Trials ISRCTN76271778

BackgroundVaginal lactobacilli offer protection against recurrent urinary infections, bacterial vaginosis, and vaginal candidiasis.ObjectiveTo characterise the isolated vaginal lactobacilli strains for their probiotic properties and to compare their probiotic potential.MethodsThe Lactobacillus strains were isolated from vaginal samples by conventional culturing and identified by sequencing of the 16S rDNA fragment. Several functional properties were detected (production of hydrogen peroxide and lactic acid; antagonistic activity against Escherichia coli, Candida albicans, Candida glabrata, and Gardnerella vaginalis; auto-aggregation and adhesiveness) as well as safety (haemolytic activity, antibiotic susceptibility, presence of transferrable resistance genes).ResultsA total of 135 vaginal lactobacilli strains of three species, Lactobacillus crispatus (56%), Lactobacillus jensenii (26%), and Lactobacillus gasseri (18%) were characterised using several functional and safety tests. Most of L. crispatus (89%) and L. jensenii (86%) strains produced H2O2. The best lactic acid producers were L. gasseri (18.2±2.2 mg/ml) compared to L. crispatus (15.6±2.8 mg/ml) and L. jensenii (11.6±2.6 mg/ml) (p<0.0001; p<0.0001, respectively). L. crispatus strains showed significantly higher anti-E. coli activity compared to L. jensenii. L. gasseri strains expressed significantly lower anticandidal activity compared to L. crispatus and L. jensenii (p<0.0001). There was no significant difference between the species in antagonistic activity against G. vaginalis. Nearly a third of the strains were able to auto-aggregate while all the tested strains showed a good ability to adhere to HeLa cells. None of the tested lactobacilli caused haemolysis. Although phenotypical resistance was not found to ampicillin, chloramphenicol, erythromycin, gentamycin, tetracycline, and vancomycin, the erm(B), tet(M), and tet(K) were detected in some strains. All strains were resistant to metronidazole, trimethoprim/sulfamethoxazole, and kanamycin.ConclusionsOur study revealed that the production of different antimicrobial metabolites is highly strain-specific and that the metabolites are not correlated with each other. L. crispatus displays better antagonistic activity against E. coli and Candida spp. than L. gasseri and L. jensenii; therefore; a potential probiotic candidate could be found among L. crispatus strains.

The composition of intestinal microbiota and the Bifidobacterium group community in 20 allergic and 20 nonallergic 5-year-old children was visualized by PCR-denaturing gradient gel electrophoresis (DGGE). The number of dominant bands in the DGGE profiles was smaller in allergic children than in nonallergic children (P<0.001). Allergic children mainly formed a single group upon cluster analysis, whereas nonallergic children were divided between four different groups. In allergic children the Bifidobacterium adolescentis species prevailed, and in nonallergic children the Bifidobacterium catenulatum/pseudocatenulatum prevailed (P=0.01 and P=0.01, respectively). The less diverse composition of intestinal microbiota and prevalence of particular species of Bifidobacterium were characteristic of allergic children even at the age of 5 years.

Very few studies have analyzed how the composition of mother’s microbiota affects the development of infant’s gut and oral microbiota during the first months of life. Here, microbiota present in the mothers’ gut, vagina, breast milk, oral cavity, and mammary areola were compared with the gut and oral microbiota of their infants over the first six months following birth. Samples were collected from the aforementioned body sites from seven mothers and nine infants at three different time points over a 6-month period. Each sample was analyzed with 16S rRNA gene sequencing. The gut microbiota of the infants harbored distinct microbial communities that had low similarity with the various maternal microbiota communities. In contrast, the oral microbiota of the infants exhibited high similarity with the microbiota of the mothers’ breast milk, mammary areola and mouth. These results demonstrate that constant contact between microbial communities increases their similarity. A majority of the operational taxonomic units in infant gut and oral microbiota were also shared with the mothers’ gut and oral communities, respectively. The disparity between the similarity and the proportion of the OTUs shared between infants’ and mothers’ gut microbiota might be related to lower diversity and therefore competition in infants’ gut microbiota.

The present study aimed at assessing the counts and species distribution of intestinal lactobacilli and exploring if the data are associated with BMI and blood glucose level in healthy adults and elderly persons. The BMI (P,0·01), the level of fasting blood glucose (P,0·001) and the total counts of lactobacilli (P, 0·01 by bacteriology; P,0·001 by real-time PCR) were higher in the elderly. The number of species in adults was lower (P, 0·05), who were more often colonised with Lactobacillus acidophilus (P¼0·031) and L. helveticus (P, 0·001). In contrast, L. plantarum (P¼ 0·035), L. paracasei (P,0·001) and L. reuteri (P¼ 0·031) were more prevalent in the elderly. L. rhamnosus was detected in adults (P, 0·001), but not in any elderly person. BMI was associated with counts of lactobacilli, adjusted for age and sex (P¼ 0·008). The higher BMI in both groups of persons was associated with the presence of obligate homofermentative lactobacilli and L. sakei, both adjusted for age and sex. Plasma glucose values were positively correlated with BMI and negatively correlated with colonisation with L. paracasei (P¼ 0·0238) in adults and on the borderline with L. fermentum (P¼0·052) in the elderly. Thus, the species-specific PCR analysis of Lactobacillus sp. combined with viable plating data indicates substantial age-related structural differences in the intestinal lactobacilli communities. The higher counts of intestinal Lactobacillus sp. are associated with higher BMI and blood glucose content, while their specific fermentative groups and species of lactobacilli appear at different glucose levels both in adults and in the elderly.

Indigenous intestinal microflora (including lactobacilli) has an important role in protection against Clostridium difficile infection. To assess in vitro interaction between lactobacilli and C. difficile, antagonistic activity of 50 intestinal Lactobacillus spp. strains against 23 pathogenic C. difficile strains was determined. Phenotypic properties of C. difficile strains [production of short-chain fatty acids (SCFAs) and toxin A, and antimicrobial susceptibility] and lactobacilli (production of SCFAs and H 2 O 2 ) were investigated. Five lactobacilli (Lactobacillus paracasei and Lactobacillus plantarum species) were antagonistic to all C. difficile strains, 18 were antagonistic to some C. difficile strains and 27 showed no antagonistic activity. This antagonistic activity was strain-specific and seemed to correlate with H 2 O 2 and lactic acid production. C. difficile strains that were more sensitive to lactobacilli (n ¼ 9) usually produced higher toxin levels and more SCFAs, and were more resistant to antibiotics, than strains that were resistant to lactobacilli (n ¼ 14). Compatibility of C. difficile strain properties (resistance to lactobacilli or antibiotics) with intestinal microecological conditions (e.g. presence of antagonistic lactobacilli, concentration of antibiotics) may determine expression of disease.

Objective: an increasing number of studies that are using high-throughput molecular methods are rapidly extending our knowledge of gut microbial colonization in preterm infants whose immaturity and requirement for extensive treatment may result in altered colonization process. We aimed to describe the profile of gut microbiota in 50 extremely low birth weight (<1200 g) critically ill infants at three different time points during the first two months of life by using 16S rrNa gene specific sequencing.Patients and Methods: Stool samples were collected at the age of one week, one month and two months. Bacterial community profiling was done using universal amplification of 16S rrNa gene and 454 pyrosequencing.results: The diversity of gut microbiota in preterm neonates in the first week of life was low but increased significantly over two months. The gut microbiota was dominated by facultative anaerobic bacteria (Staphylococcus spp. and Enterobacteriaceae) and lacked colonization with bacteria known to provide resistance against pathogens (Bacteroides, Bifidobacterium, and Lactobacillus) throughout the study. Colonization of Escherichia coli and uncultured Veillionella was positively correlated with maturity. Infants born to mothers with chorioamnionitis had significantly higher bacterial diversity than those without.Conclusions: High prevalence and abundance of potentially pathogenic Enterobacteriaceae and Staphylococcaceae with low prevalence and abundance of colonization resistance providing taxa bifidobacteria, Bacteroides and lactobacilli may lead to high infection risk via microbial translocation from the gut. additionally, our data suggest that maternal chorioamnionitis may have an effect on the diversity of infants' gut microbiota; however, the mechanisms involved remain to be elucidated.

Safety of the probiotic Lactobacillus plantarum strain Tensia (DSM 21380) was tested in vitro, in semihard Edam-type cheese, in an animal model and after consumption of the probiotic cheese in double-blind randomized placebo-controlled human intervention studies with different age groups. The susceptibility of L. plantarum Tensia to 8 antibiotics, and the presence of tetracycline (tet M, S, O, K, L) genes and class 1 integron was assessed by applying epsilometer-test and PCR-based methods. Production of biogenic amines by the probiotic strain in decarboxylation medium containing 1% of l-histidine, l-glutamine, l-ornithine, l-arginine, or l-lysine and in cheese was tested by gas chromatography. The biosafety of L. plantarum Tensia was evaluated on National Institutes of Health-line mice fed cheese containing Tensia at a concentration of 9.6 log cfu/g for 30 consecutive days. In human intervention trials in adults and the elderly, the effects of different doses of Edam-type cheese and the probiotic bacterium on BW, gut functionality indices, and host metabolism were evaluated. The strain L. plantarum Tensia was susceptible to all tested antibiotics and did not possess the tetracycline resistance-determining genes tet(L), tet(S) and tet(O), nor did it contain the integron (Int1) gene. However, the strain was tet(K) and tet(M) positive. Lactobacillus plantarum Tensia did not produce potentially harmful biogenic amines, such as histamine or cadaverine. The amount of tyramine produced in the cheese environment during ripening and after 15 wk of storage was below the clinically significant content. In the animal model, no translocation of the administered strain or other microbes into the blood or organs of mice was detected. No harmful effect was observed on body mass index, inflammatory markers, or serum lipidograms during human intervention trials with different age groups at a daily dose of 10.3 or 8.17 log cfu/serving for 3 wk. No negative effect on gastrointestinal welfare was observed, but the consumption of 100g/d for 3 wk caused hard stools from the second week of the trial. The content of total lactobacilli increased in feces, and the presence of the ingested probiotic strain was confirmed after the consumption of cheese. Thus, L. plantarum strain Tensia is suitable for generally recognized as safe (GRAS) and qualified presumption of safety (QPS) criteria because it did not have any undesirable characteristics. The regular semihard Edam-type cheese (fat content of 26%) with the probiotic additive at a daily dose of 50 g or in excess (100g) and with a probiotic daily dose of 10 log cfu for 3 wk was safe.