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Probiotics, in particular Lactobacillus (lactic acid bacteria, LAB) strains, are widely used in clinical practice. Despite that these probiotics have GRAS (generally regarded as safe) and qualified presumption of safety (QPS) statuses, the safety of particular strains still needs to be thoroughly studied. The aim of the study was to evaluate the safety of Lact. casei IMV B-7280 strain by investigating toxicity and the effects on gut microbiota in experimental animal model. Male BALB/c mice (7–8 weeks, weight 20–24 g) were treated with amounts of Lact. casei IMV B-7280 strain: 5 × 106, 5 × 108, or 5 × 109 CFU/animal once per day during 7 days, or in the amount of 1 × 1010 CFU/animal once per day during 3 days (most of the proposed probiotic doses for humans—from 108 to 109 CFU) and monitored during 14 days. Blood tests and serum biochemistry were conducted; the cecal content from mice of the experimental and control groups were freshly collected and analyzed. At the end of the experiments (15th day), the presence of LAB in the heart, liver, kidney, and mesenteric lymph nodes and peripheral blood was determined; histology of the brain, liver, heart, fragments of the small and large intestine, and mesenteric lymph nodes was conducted. Survival rate of BALB/c mice treated with Lact. casei IMV B-7280 strain in different concentrations in toxicity experiments during 14 days was 100%. We observed no signs of toxicity as changes in gait, lethargy, sleep, somatomotor activity as well as changes in fur, eyes, skin and mucous membranes, tremors, behavior pattern, convulsions, salivation, diarrhea, and local injuries in mice from all experimental groups. After administration of probiotic strain, the number of opportunistic bacteria in cecal contents, such as Staphylococcus spp., Candida spp., Pseudomonas spp., and total aerobic and optionally anaerobic bacteria decreased compared to controls; the population of beneficial bacteria such as lactobacilli increased in cecal contents of these mice. LAB were not detected in the peripheral blood, heart, liver, kidneys, and mesenteric lymph nodes after administration of this strain to intact mice. Lact. casei IMV B-7280 strain is safe at dose up to 1010 CFU/animal during 3- and 7-day oral administration to mice and has a positive effect on the gut microbiota composition; it could be potentially considered as safe probiotic for humans.

Aim. To provide practical recommendations on the use of probiotics for the treatment and prevention of gastroenterological diseases in adults.General provisions. Probiotics are living microorganisms that benefit the health of the host when administered in adequate amounts. The main functions of probiotics include the support for colonisation resistance, the metabolism of food substrates and utilisation of end metabolites, the production of substrates necessary for the macro-organism, as well as the regulation of local and adaptive immune responses. Probiotics can be registered in the Russian Federation as biologically active food additives (BAFA) or as pharmaceutical products (drugs) in accordance with the microbiological standards and legislative requirements of the Russian Federation. The probiotics registered in the Russian Federation as BAFA for adults include bacteria of the Lactobacillus, Bifidobacterium, Enterococcus, Pediococcus, Lactococcus, Streptococcus, Bacillus, and Escherichia genera, and fungi of the Saccharomyces genus; probiotics registered as drugs — bacteria of Lactobid, Lactobacid, Escherichia and Enterococcus genera and fungi of the Saccharomyces genus. Some probiotics registered in the Russian Federation include probiotic strains that have proved to be effective for the prevention and treatment of antibiotic-associated diarrhea, the prevention of C. difficile-associated disease, the eradication of H. pylori infection, as well as for the treatment of irritable bowel syndrome and functional constipation.Conclusions. The clinical efficacy of probiotics depends on the probiotic strains included in their composition and is confirmed by a comparative analysis of the results of appropriate clinical studies. Not all probiotics registered in the Russian Federation as BAFA or drugs contain bacterial or fungal strains; as a result, the expected clinical effect may not be achieved.

Aim to study antibacterial activity of benzydamine hydrochloride, against clinic isolated of bacteria, located in hospitals in Russia and compare this data to results of similar trail of Spanish isolates. Materials and method for this study were used clinical isolates of bacteria, which are counted as typical agents of infections in otorhinolaryngology and gynecology. Enterococcus spp., Escherichia coli, Klebsiella pneumoniae, Staphylococcus spp. and Streptococcus spp., isolated from patients in Russians hospitals; reference strains Escherichia coli, Staphylococcus aureus and Streptococcus agalactiae, from ATCC collection; and also, Lactobacillus acidophilus strain, isolated from probiotic drug «Lactobacterin». Antibacterial activity of benzydamine hydrochloride was evaluated with serial dilution method in agar. For comparison of results we used data of Spanish study of benzydamine activity against clinical isolates and reference strains. The Spanish Study was completed in microbiological department of San-Pau hospital in Barcelona in 2001. Results . It was indicated that minimum inhibitory concentration (MIC) of benzydamine hydrochloride for clinical isolates of gram-negative and gram-positive bacteria, isolated from Russian and Spanish hospitals is about the same level: for E. coli it was 640 – 1280 mg/l, for K. pneumoniae – 512–1280 mg/l, for S. aureus – 256–1280 mg/l, for S. agalactiae – 320–1280 mg/l, for S. pyogenes – 256–640 mg/l, for E. faecalis – 512 mg/l, for E. faecium – 256 mg/l, for S. mitis – 640 mg/l, for S. epidermidis 320 – 1280 mg/l, for S. pneumoniae – 40 mg/l, for S. viridans – 40 mg/l. The same data was obtained by assessment of sensitivity to benzydamine hydrochloride reference-strains from ATCC collection: for E. coli MIC was 512 – 640 mg/l, for S. aureus – 512 – 640 mg/l, for S. agalactiae – 320 mg/l, for S. pneumoniae – 640 mg/l. Probiotic strain L. acidophilus was resistant to benzydamine hydrochloride activity with MIC = 20000 mg/l. Conclusion : It was indicated that antimicrobial activity of benzydamine hydrochloride against clinical strains, isolated from the patients of hospitals in Russia and Spain. Also, resistance of probiotic strain of lactobacteria was detected to this drug, which indicates the possibility of benzydamine hydrochloride application in clinical practice in otorhinolaryngology and gynecology without risk of negative influence on normal lactobacterial flora.

Traditionally fermented fish and meat products are known for their probiotic values. An approach was made for the very first time to isolate and characterize novel indigenous probiotic bacterial strains from traditionally fermented fish and meat products of Assam, India, which is known as the biodiversity hotspot of the country with largely unexplored economically important microorganisms. The most potent probiotic isolate was identified as Staphylococcus sp. DBOCP6 (GenBank accession no. KR706310) on the basis of 16S rDNA sequencing technique. The new isolate was found to be non-hemolytic and nonpathogenic on the basis of its susceptibility against broad and narrow spectrum antibiotics. It shows antagonistic effect against E. coli MTCC 40. Its viability in presence of lysozyme, bile salt (4%), and a pH range of 1–10 signifies its ability to survive throughout the gastrointestinal tract. It also shows significant value of hydrophobicity (33.1%) along with a higher value of auto-aggregation (71.43%) indicates its ability to adhere to the intestinal wall on the basis of its cell surface traits. The high thermal death point of the isolate (100 °C) indicates its suitability for further commercial exploitation. Based on the above observations, it could be concluded that the novel Staphylococcus sp. strain DBOCP6 can serve as a potential probiotic candidate for industrial exploitation.

A large number of commensal bacteria inhabit the intestinal tract, and interbacterial communication among gut microbiota is thought to occur. In order to analyze symbiotic relationships between probiotic strains and the gut microbiota, a ring with a membrane filter fitted to the bottom was used for in vitro investigations. Test strains comprising probiotic nitto strains (Lactobacillus acidophilus NT and Bifidobacterium longum NT) and type strains (L. acidophilus JCM1132T and B. longum JCM1217T) were obtained from diluted fecal samples using the membrane filter to simulate interbacterial communication. Bifidobacterium spp., Streptococcus pasteurianus, Collinsella aerofaciens, and Clostridium spp. were the most abundant gut bacteria detected before coculture with the test strains. Results of the coculture experiments indicated that the test strains significantly promote the growth of Ruminococcus gnavus, Ruminococcus torques, and Veillonella spp. and inhibit the growth of Sutterella wadsworthensis. Differences in the relative abundances of gut bacterial strains were furthermore observed after coculture of the fecal samples with each test strain. Bifidobacterium spp., which was detected as the dominant strain in the fecal samples, was found to be unaffected by coculture with the test strains. In the present study, interbacterial communication using bacterial metabolites between the test strains and the gut microbiota was demonstrated by the coculture technique. The detailed mechanisms and effects of the complex interbacterial communications that occur among the gut microbiota are, however, still unclear. Further investigation of these relationships by coculture of several fecal samples with probiotic strains is urgently required.

Nocellara Etnea is one of the main Sicilian cultivars traditionally used to produce both olive oil and naturally fermented table olives. In the present study, the effect of different salt concentrations on physico-chemical, microbiological, sensorial, and volatile organic compounds (VOCs) formation was evaluated in order to obtain functional Nocellara Etnea table olives. The experimental design consisted of 8 treatments as follow: fermentations at 4, 5, 6, and 8% of salt with (E1-E4 samples) and without (C1-C4 samples) the addition of starters. All the trials were carried out at room temperature (18 +/- 2 degrees C) and monitored for an overall period of 120 d. In addition, the persistence of the potential probiotic Lactobacillus paracasei N24 at the end of the process was investigated. Microbiological data revealed the dominance of lactic acid bacteria (LAB), starting from the 7th d of fermentation, and the reduction of yeasts and enterobacteria in the final product inoculated with starters. VOCs profile highlighted a high amount of aldehydes at the beginning of fermentation, which significantly decreased through the process and a concomitant increase of alcohols, acids, esters, and phenols. In particular, esters showed an occurrence percentage higher in experimental samples rather than in control ones, contributing to more pleasant flavors. Moreover, acetic acid, ethanol, and phenols, which often generate off-flavors, were negatively correlated with mesophilic bacteria and LAB. It is interesting to note that salt content did not affect the performances of starter cultures and slightly influenced the metabolome of table olives. Sensory data demonstrated significant differences among samples registering the highest overall acceptability in the experimental sample at 5% of NaCl. The persistence of the L. paracasei N24 strain in experimental samples, at the end of the process, revealed its promising perspectives as starter culture for the production of functional table olives with reduced salt content.

Bacillus coagulans GBI-30, 6086 is a safe strain, already available on the market, and characterized by certified beneficial effects. The draft genome sequence presented here constitutes the first pillar toward the identification of the molecular mechanisms responsible for its positive features and safety.

Lactobacillus reuteri strain ATCC 55730 (LB BIO) was isolated as a pure culture from a Reuteri tablet purchased from the BioGaia company. This probiotic strain produces a soluble glucan (reuteran), in which the majority of the linkages are of the α-(1→4) glucosidic type (∼70%). This reuteran also contains α-(1→6)- linked glucosyl units and 4,6-disubstituted α-glucosyl units at the branching points. The LB BIO glucansucrase gene ( gtfO ) was cloned and expressed in Escherichia coli , and the GTFO enzyme was purified. The recombinant GTFO enzyme and the LB BIO culture supernatants synthesized identical glucan polymers with respect to linkage type and size distribution. GTFO thus is a reuteransucrase, responsible for synthesis of this reuteran polymer in LB BIO. The preference of GTFO for synthesizing α-(1→4) linkages is also evident from the oligosaccharides produced from sucrose with different acceptor substrates, e.g., isopanose from isomaltose. GTFO has a relatively high hydrolysis/transferase activity ratio. Complete conversion of 100 mM sucrose by GTFO nevertheless yielded large amounts of reuteran, although more than 50% of sucrose was converted into glucose. This is only the second example of the isolation and characterization of a reuteransucrase and its reuteran product, both found in different L. reuteri strains. GTFO synthesizes a reuteran with the highest amount of α-(1→4) linkages reported to date.

Lactobacillus reuteri strain ATCC 55730 (LB BIO) was isolated as a pure culture from a Reuteri tablet purchased from the BioGaia company. This probiotic strain produces a soluble glucan (reuteran), in which the majority of the linkages are of the α-(1→4) glucosidic type (∼70%). This reuteran also contains α-(1→6)-linked glucosyl units and 4,6-disubstituted α-glucosyl units at the branching points. The LB BIO glucansucrase gene (gtfO) was cloned and expressed in Escherichia coli, and the GTFO enzyme was purified. The recombinant GTFO enzyme and the LB BIO culture supernatants synthesized identical glucan polymers with respect to linkage type and size distribution. GTFO thus is a reuteransucrase, responsible for synthesis of this reuteran polymer in LB BIO. The preference of GTFO for synthesizing α-(1→4) linkages is also evident from the oligosaccharides produced from sucrose with different acceptor substrates, e.g., isopanose from isomaltose. GTFO has a relatively high hydrolysis/transferase activity ratio. Complete conversion of 100 mM sucrose by GTFO nevertheless yielded large amounts of reuteran, although more than 50% of sucrose was converted into glucose. This is only the second example of the isolation and characterization of a reuteransucrase and its reuteran product, both found in different L. reuteri strains. GTFO synthesizes a reuteran with the highest amount of α-(1→4) linkages reported to date. Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Lactobacillus reuteri strain ATCC 55730 (LB BIO) was isolated as a pure culture from a Reuteri tablet purchased from the BioGaia company. This probiotic strain produces a soluble glucan (reuteran), in which the majority of the linkages are of the α-(1→4) glucosidic type (∼70%). This reuteran also contains α-(1→6)-linked glucosyl units and 4,6-disubstituted α-glucosyl units at the branching points. The LB BIO glucansucrase gene (gtfO) was cloned and expressed in Escherichia coli, and the GTFO enzyme was purified. The recombinant GTFO enzyme and the LB BIO culture supernatants synthesized identical glucan polymers with respect to linkage type and size distribution. GTFO thus is a reuteransucrase, responsible for synthesis of this reuteran polymer in LB BIO. The preference of GTFO for synthesizing α-(1→4) linkages is also evident from the oligosaccharides produced from sucrose with different acceptor substrates, e.g., isopanose from isomaltose. GTFO has a relatively high hydrolysis/transferase activity ratio. Complete conversion of 100 mM sucrose by GTFO nevertheless yielded large amounts of reuteran, although more than 50% of sucrose was converted into glucose. This is only the second example of the isolation and characterization of a reuteransucrase and its reuteran product, both found in different L. reuteri strains. GTFO synthesizes a reuteran with the highest amount of α-(1→4) linkages reported to date. Copyright © 2005, American Society for Microbiology. All Rights Reserved.