Evaluation of Bacillus clausii CSI08, Bacillus megaterium MIT411 and a Bacillus cocktail on gastrointestinal health: a randomised, double-blind, placebo-controlled pilot study

In the present study, the safety, tolerance and impact of 1×10⁹ cfu Bacillus clausii CSI08, 1×10⁹ cfu Bacillus megaterium MIT411 and a probiotic cocktail containing Bacillus subtilis DE111^®, Bacillus megaterium MIT411, Bacillus coagulans CGI314, and Bacillus clausii CSI08 with a total count of 2.0×10⁹ cfu administered daily were assessed as compared with a maltodextrin containing placebo control. A total of 98 study participants received daily doses for 45 days, followed by a washout period of 2 weeks. A questionnaire to capture the incidence and duration of upper respiratory tract, urinary tract and/or gastrointestinal complaints and a diary to capture stool regularity and consistency was kept daily to record compliance throughout the 45 days. Faecal and blood samples were collected for microbiological and haematological analysis at the start and end of the treatment period. The probiotic cocktail significantly decreased the incidence of loose stools throughout the entire study. The recorded respiratory, urinary and gastrointestinal symptoms, defecation frequency and other stool consistency were not influenced. No clinically relevant changes in blood parameters, such as liver and kidney function and no serious adverse events appeared during and after administration. There were no changes in symptoms including sadness, irritability, energy, appetite, tension, stress, sleep, cardiovascular events, aches and pains, and dizziness as determined by a mood questionnaire administered to participants at baseline and at the end of the treatment period. Similarly, the measured inflammatory cytokines, antioxidant levels, cholesterol, triglycerides, free amino acids or minerals remained unaffected. There were no negative changes in alpha or beta diversity of the microbiota with any of the treatment groups. These promising data suggest that these treatments were safe and well tolerated, and further work with larger cohorts are justified to determine the efficacy of these potential probiotics in select demographic groups. Trial registration number with clinicaltrials.gov at NCT04758845.

Anti-obesity properties of the strain Bifidobacterium animalis subsp. lactis CECT 8145 in Zücker fatty rats

We evaluated the effect of oral administration of Bifidobacterium animalis subsp. lactis CECT 8145 strain in Zücker fatty rats. The Zücker fatty rats were randomly divided into two groups (n=10 each) and administered either B. animalis subsp. lactis CECT 8145 (1010 cfu/day) suspended in skim milk, or skim milk alone (control group). Each treatment was administered in drinking bottles from week 5 until week 17 of age. A lean Zücker rat group (standard group) was included to provide normal values for the Zücker strain. This group was administered skim milk in the drinking bottle for the same experimental period as Zücker fatty rats. Body weight gain was greater in the fatty control group than in the fatty rats treated daily with B. animalis subsp. lactis CECT 8145. Furthermore, dry and liquid food intake significantly decreased in the treated Zücker fatty group and these rats also showed decreased plasma ghrelin levels as compared with the Zücker fatty control group. B. animalis subsp. lactis CECT 8145 intake also decreased plasma tumour necrosis factor-α (a proinflammatory cytokine) and plasma malondialdehyde (a biomarker of oxidative stress). Moreover, the ratio plasma total cholesterol/plasma cholesterol transported by high-density lipoproteins, considered as an index for cardiovascular disease, also significantly decreased in the Zücker fatty rats treated with B. animalis subsp. lactis CECT 8145. By contrast, this bacterial strain significantly increased plasma adiponectin (an insulin-sensitising adipokine), but did not produce significant effects on triglyceride levels or glucose metabolism biomarkers. Although further research is required to confirm B. animalis subsp. lactis CECT 8145 is an efficient anti-obesity treatment in humans, the results obtained in this study are promising and point to the health and anti-obesity properties of this bacterial strain.

Probiotic administration improves sperm quality in asthenozoospermic human donors

The objective of this study is to analyse the effect of the ingestion of two selected antioxidant probiotics strains (Lactobacillus rhamnosus CECT8361 and Bifidobacterium longum CECT7347) on sperm quality parameters in asthenozoospermic males after three and six weeks of administration. Nine asthenozoospermic men without any medical treatment under similar diet conditions participated in the study. The quality of individual sperm samples was evaluated before (previous to ingestion), during (after 3 and 6 weeks of ingestion) and after probiotic administration (3 and 6 weeks after finishing the treatment). Sperm motility was evaluated by computer-assisted sperm analysis system, DNA fragmentation by sperm chromatin structure assay, cell viability by flow cytometry and measurement of intracellular H₂O₂ (reactive oxygen species; ROS) by flow cytometry using dichloro-dihydrofluorescein diacetate. Sperm motility was drastically improved after the treatment (approximately 6 fold change), DNA fragmentation was statistically reduced after probiotic administration from (approximately 1.2 fold change) and intracellular H₂O₂ level was decreased (approximately 3.5 fold change). Cell viability was not affected by the treatment. The significant improvement in sperm motility and the decrease in DNA fragmentation reported in this study provide preliminary evidence that probiotics could be administrated to improve motility and decrease DNA fragmentation and ROS levels in asthenozoospermic human males.

Probiotic yeast Kluyveromyces marxianus CIDCA 8154 shows anti-inflammatory and anti-oxidative stress properties in in vivo models

Inflammatory bowel diseases (IBDs) are complex affections with increasing incidence worldwide. Multiple factors are involved in the development and maintenance of the symptoms including enhanced oxidative stress in intestinal mucosa. The conventional therapeutic approaches for IBDs are based on the use anti-inflammatory drugs with important collateral effects and partial efficacy. In the present work we tested the anti-inflammatory capacity of Kluyveromyces marxianus CIDCA 8154 in different models. In vitro, we showed that the pretreatment of epithelial cells with the yeast reduce the levels of intracellular reactive oxygen species. Furthermore, in a murine model of trinitro benzene sulfonic acid-induced colitis, yeast-treated animals showed a reduced histopathological score (P<0.05) and lower levels of circulating interleukin 6 (P<0.05). The capacity to modulate oxidative stress in vivo was assessed using a Caenorhabditis elegans model. The yeast was able to protect the nematodes from oxidative stress by modulating the SKN-1 transcription factor trough the DAF-2 pathway. These results indicate that K. marxianus CIDCA 8154 could control the intestinal inflammation and cellular oxidative stress. Deciphering the mechanisms of action of different probiotics might be useful for the rational formulation of polymicrobial products containing microorganisms targeting different anti-inflammatory pathways.

Sublethal injury and virulence changes in Listeria monocytogenes and Listeria innocua treated with antimicrobials carvacrol and citral

The aim of this study was to evaluate the effect of two antimicrobial substances, carvacrol and citral, on Listeria monocytogenes and Listeria innocua cells, as well as possible virulence changes in injured cells, using Caenorhabditis elegans as a model test. The results indicated that the percentage of sublethal damage was higher in L. monocytogenes than in L. innocua. The results of the study carried out by using C. elegans indicated that C. elegans fed in a lawn of L. monocytogenes previously treated with carvacrol showed a loss in life span (p ≤ 0.05) as compared with L. monocytogenes treated with citral, Escherichia coli OP50 as a negative control, and treated and untreated L. innocua. Egg laying was also affected: worms fed in a lawn of treated and untreated L. monocytogenes laid fewer eggs than those fed in a lawn of treated and untreated L. innocua or fed with OP50 as a negative control. Worms fed in a lawn of treated and untreated L. innocua also laid fewer eggs than those fed with OP50 as a negative control. A phenotype named bag of worms and an undescribed new one, "vulva inflammation", were also observed.

Enumeration and Identification of 4-Ethylphenol Producing Yeasts Recovered from the Wood of Wine Ageing Barriques after Different Sanitation Treatments

<p>Aims: This work was aimed at the evaluation of several sanitation procedures on the reduction of total microbial flora and of <em>D. bruxellensis</em> recovered from the inner layers of the barrique’s wood.</p> <p>Methods: A group of used oak barrels tainted by 4-ethylphenol and contaminated with <em>D. bruxellensis</em> were differently sanitized and, afterwards, were dismantled to analyse samples of shaves taken from wood surfaces at different depths. Microbial counts were obtained by the Most Probable Number Technique using broths of general purpose medium and of <em>Dekkera</em>/<em>Brettanomyces </em>differential medium (DBDM).</p> <p>Results: The least inefficient treatment included barrique steaming at low pressure. Uncontaminated samples were only detected under this treatment and in the upper level (0-2 mm) of the staves. With this treatment complete destruction of the contaminating flora was not achieved in any level of stave side surfaces and in grooves. The presence of <em>D. bruxellensis </em>was detected in depths up to 6-8 mm in the wood corresponding to the maximum level of wine penetration.</p> <p>Significance: this work demonstrated that even after current sanitation procedures barriques used in wine maturation pose a severe risk to wine stability due to the presence of <em>D. bruxellensis</em>.</p>

Rapid identification and enumeration of Saccharomyces cerevisiae cells in wine by real-time PCR

Despite the beneficial role of Saccharomyces cerevisiae in the food industry for food and beverage production, it is able to cause spoilage in wines. We have developed a real-time PCR method to directly detect and quantify this yeast species in wine samples to provide winemakers with a rapid and sensitive method to detect and prevent wine spoilage. Specific primers were designed for S. cerevisiae using the sequence information obtained from a cloned random amplified polymorphic DNA band that differentiated S. cerevisiae from its sibling species Saccharomyces bayanus, Saccharomyces pastorianus, and Saccharomyces paradoxus. The specificity of the primers was demonstrated for typical wine spoilage yeast species. The method was useful for estimating the level of S. cerevisiae directly in sweet wines and red wines without preenrichment when yeast is present in concentrations as low as 3.8 and 5 CFU per ml. This detection limit is in the same order as that obtained from glucose-peptone-yeast growth medium (GPY). Moreover, it was possible to quantify S. cerevisiae in artificially contaminated samples accurately. Limits for accurate quantification in wine were established, from 3.8 x 10(5) to 3.8 CFU/ml in sweet wine and from 5 x 10(6) to 50 CFU/ml in red wine.