In vitro evaluation on HeLa cells of protective mechanisms of probiotic lactobacilli against Candida clinical isolates

Aims: To characterize in vitro the ability of human Lactobacillus strains to inhibit the adhesion, to displace and to compete with clinically isolated Candida strains. Methods and Results: Three types of assays were performed to determine the inhibitory effect of Lactobacillus plantarum 319, Lactobacillus rhamnosus IMC 501, Lactobacillus paracasei IMC 502 and a specific probiotic combination (SYNBIO) on adhesion of Candida pathogens to HeLa cells: blockage by exclusion (lactobacilli and HeLa followed by pathogens), competition (lactobacilli, HeLa and pathogens together) and displacement (pathogens and HeLa followed by the addition of lactobacilli). Bacterial adhesion to HeLa was quantified by microscopy after May-Grunwald/Giemsa stain. The inhibition results highlight a significant (P < 0.05) competition of the considered probiotics against all the Candida strains. The results suggest that the probiotic strains used in this study could prevent colonization of the urogenital tract by relevant pathogens such as Candida strains through barrier and interference mechanisms (mainly displacement and competition), but the degree of inhibition of adhesion was bacterial strain-dependent. Conclusions: The results support the potential of these Lactobacillus probiotic strains as anti-infective agents in the vagina and encourage further studies about their capacity to prevent and manage urogenital tract infections in females. Significance and Impact of the Study: To optimize the defensive properties of the vaginal microbiota, improving the health of many women by probiotic intervention

Impact of a probiotic diet on well-being of healthy senior: THE PROBIOSENIOR PROJECT

Aims: The aim of this work was to assess the effects of a probiotic diet on well-being of healthy seniors living in boarding and private homes in Marche Region, Italy. In particular, we focused on the modulation of high-sensitivity C-reactive protein (HsCRP), intestinal microbiota and short-chain fatty acids (SCFAs). Methods and Results: Ninety-seven healthy seniors took part in a double-blind, placebo-controlled feeding study (59 fed probiotics, 38 fed placebo) for 6&nbsp;months. Each volunteer ingested daily one food product or a dietary supplement enriched with Synbio® blend (Synbiotec Srl, Camerino, Italy) or the placebo (control group). Blood and faecal samples were collected before and at the end of the intervention period to perform biochemical and microbiological analyses. The serum HsCRP difference value after 6&nbsp;months of treatment was significantly higher in the probiotic group than placebo (p &lt; 0.05). After the intervention, a significant increase in faecal lactobacilli and a bifidobacteria increase in more participants were observed in the probiotic group. The 16S NGS analysis on the probiotic group showed a decreasing trend of Proteobacteria at the end of the treatment and conversely, an increasing trend of Actinobacteria and Verrucomicrobia phyla, to which the increase of Akkermansiaceae and Bifidobacteriaceae contributes at the family level. Finally, total short-chain fatty acids (SCFAs) and butyric acid were significantly higher in the probiotic group at the end of the treatment respect to the beginning. Conclusions: Overall, this study emphasizes the beneficial anti-inflammageing effect of a prolonged diet based on functional foods enriched with Synbio® through the modulation of the intestinal microbiota and the consequent increase in the SCFA production. Significance and Impact of the Study: Synbio® integration in elderly daily diet may be a preventive strategy to support healthy ageing

Evaluation of Commercial Probiotic Products

Although there is a vast number of probiotic products commercially available due to their acceptability and increasing usage, their quality control has continuously been a major concern. This study aimed to assess some commercially available probiotics on the UK market for content in relation to their label claim. Seven products were used for the study. The bacteria content were isolated, identified and enumerated on selective media. The results revealed that all products evaluated contained viable probiotic bacteria but only three out of the seven products (43%) contained the claimed culture concentration or more. None of the multispecies product contained all the labelled probiotic bacteria. Misidentification of some species occurred. The results concurred with previous studies and showed that quality issues with commercial probiotics remain. Since probiotic activity is linked with probiotic concentration and is strain specific, the need exist for a global comprehensive legislation to control the quality of probiotics whose market is gaining huge momentum

Non-target impact of fungicide tetraconazole on microbial communities in soils with different agricultural management

Effect of the fungicide tetraconazole on microbial community in silt loam soils from orchard with long history of triazole application and from grassland with no known history of fungicide usage was investigated. Triazole tetraconazole that had never been used on these soils before was applied at the field rate and at tenfold the FR. Response of microbial communities to tetraconazole was investigated during 28-day laboratory experiment by determination of changes in their biomass and structure (phospholipid fatty acids method—PLFA), activity (fluorescein diacetate hydrolysis—FDA) as well as changes in genetic (DGGE) and functional (Biolog) diversity. Obtained results indicated that the response of soil microorganisms to tetraconazole depended on the management of the soils. DGGE patterns revealed that both dosages of fungicide affected the structure of bacterial community and the impact on genetic diversity and richness was more prominent in orchard soil. Values of stress indices—the saturated/monounsaturated PLFAs ratio and the cyclo/monounsaturated precursors ratio, were almost twice as high and the Gram-negative/Gram-positive ratio was significantly lower in the orchard soil compared with the grassland soil. Results of principal component analysis of PLFA and Biolog profiles revealed significant impact of tetraconazole in orchard soil on day 28, whereas changes in these profiles obtained for grassland soil were insignificant or transient. Obtained results indicated that orchards soil seems to be more vulnerable to tetraconazole application compared to grassland soil. History of pesticide application and agricultural management should be taken into account in assessing of environmental impact of studied pesticides. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10646-016-1661-7) contains supplementary material, which is available to authorized users

Probiotic lactobacilli inhibit early stages of Candida albicans biofilm development by reducing their growth, cell adhesion, and filamentation

We evaluated the inhibitory effects of the probiotic Lactobacillus species on different phases of Candida albicans biofilm development. Quantification of biofilm growth and ultrastructural analyses were performed on C. albicans biofilms treated with Lactobacillus rhamnosus, Lactobacillus casei, and Lactobacillus acidophilus planktonic cell suspensions as well as their supernatants. Planktonic lactobacilli induced a significant reduction (p\ua0\ua00.05), but significantly reduced the early stages of Candida biofilm formation (p\ua

Probiotic characterization of Lactobacillus isolates from canine faeces

Aims: There is interest in using probiotics such as Lactobacillus species to control canine intestinal infections. The bacterial species should be of canine intestinal origin exhibiting host specificity. Bacterial strains were isolated from dog faecal samples and characterized to select specific probiotics as dietary supplements in feed, promoting health status. Methods and Results: Bacterial strains have been screened for their probiotic properties including survival to gastric and pancreatic juices and bile salts, resistance to antibiotics and antipathogenicity. Five of 14 isolated Lactobacillus strains were tolerant to gastric stress. They were also resistant to clindamycin and with a significant antimicrobial capacity towards the pathogenic strains tested, variable according to the strain. They were identified by morphological and molecular characterization comparing the 16S rRNA gene sequence with the blast database. Three strains were identified as Lactobacillus reuteri and two as Lactobacillus johnsonii. Sugar fermentation profiles and adhesion to HT29 epithelial cells have been in&nbsp;vitro verified on L. reuteri AI, chosen as probiotic candidate. Resistance to freeze-drying, production and subsequent in&nbsp;vivo administration evaluating strain permanence, were also performed. No loss of vitality has been recorded due to the freeze-drying process. The average value of recovery percentage of L. reuteri AI at the end of the administration period and after 1&nbsp;week of follow-up was respectively 26·7 and 17·4% of the total Lactobacillus sp. Conclusions: Among several selected probiotic strains, L. reuteri AI proved to be the best probiotic candidate to use as a supplement for dogs. Significance and Impact of the Study: Control of intestinal pathogenic micro-organisms in dogs is a growing concern and the selection of autochthonous probiotic bacterial strains to overcome some of the gut problems associated with the modern domestication of animals is a valuable tool

Effect of buckwheat flour and oat bran on growth and cell viability of the probiotic strains Lactobacillus rhamnosus IMC 501®, Lactobacillus paracasei IMC 502® and their combination SYNBIO®, in synbiotic fermented milk

Fermented foods have a great significance since they provide and preserve large quantities of nutritious foods in a wide diversity of flavors, aromas and texture, which enrich the human diet. Originally fermented milks were developed as a means of preserving nutrients and are the most representatives of the category. The first aim of this study was to screen the effect of buckwheat flour and oat bran as prebiotics on the production of probiotic fiber-enriched fermented milks, by investigating the kinetics of acidification of buckwheat flour- and oat bran supplemented milk fermented by Lactobacillus rhamnosus IMC 501®, Lactobacillus paracasei IMC 502® and their 1:1 combination named SYNBIO®. The probiotic strains viability, pH and sensory characteristics of the fermented fiber-enriched milk products, stored at 4 °C for 28 days were also monitored. The results showed that supplementation of whole milk with the tested probiotic strains and the two vegetable substrates results in a significant faster lowering of the pH. Also, the stability of L. rhamnosus IMC 501®, L. paracasei IMC 502® and SYNBIO® during storage at 4 °C for 28 days in buckwheat flour- and oat bran-supplemented samples was remarkably enhanced. The second aim of the study was to develop a new synbiotic product using the best combination of probiotics and prebiotics by promoting better growth and survival and be acceptable to the consumers with high concentration of probiotic strain. This new product was used to conduct a human feeding trial to validate the fermented milk as a carrier for transporting bacterial cells into the human gastrointestinal tract. The probiotic strains were recovered from fecal samples in 40 out of 40 volunteers fed for 4 weeks one portion per day of synbiotic fermented milk carrying about 10E9 viable cells

Lactobacillus strains treatment on commercial packaging paper as preliminary study for extending the shelf-life of chicken meat

Lactobacillus plantarum IMC 509 and SYNBIO® (1:1 combination of Lact. rhamnosus IMC 501® and Lact. paracasei IMC 502®), were investigated as natural anti-spoilage agents sprinkled on commercial packaging, polyethylene (PE) laminated paper sheet, to extend raw chicken breast meat shelf-life at 4°C. Slices of chicken breast meat, wrapped in commercial packaging papers sheet sprayed by Lactobacillus cell suspensions, were analyzed at 0, 2, 5, 7 days of storage. Total aerobic mesophilic bacteria, pH value, sensory changes and biogenic amines (BAs) production were checked. Lactobacillus strains viability on paper packaging was also monitored. The best ability of preserving meat parameters was observed in Lactobacillus sprayed PE laminated papers compared to control paper. The BAs extracted from meat preserved into Lact. plantarum IMC 509 sprayed PE laminated paper sheet were significantly less than other samples. Lact. plantarum IMC 509 showed a high stability, keeping its viability in all paper surfaces. It reduced both spoilage microbial growth and BAs accumulation, providing further evidence for its suitability to be used in packaging application. Lactobacillus strains may be assumed as bio-preservatives applied on papers sheet to extend chicken meat shelf-life without affecting the flavor