Strain-Specificity and Disease-Specificity of Probiotic Efficacy: A Systematic Review and Meta-Analysis

Safety and tolerance of Lacticaseibacillus paracasei N1115 in caesarean-born young children: a randomised, placebo-controlled trial

The administration of probiotics may help to improve dysbiosis and related health problems in children delivered by caesarean section. However, the effects are strain specific, and safety combined tolerance are considered a priority. The aim of this study was to evaluate the safety and tolerance of Lacticaseibacillus paracasei N1115 in caesarean-born children aged 6-24 months via a randomised, placebo-controlled intervention study. In total, 101 children were included and randomised to receive either a sachet of L. paracasei N1115 (2×1010 cfu/g, 2 g/day) or placebo (maltodextrin, 2 g/day) per day for 12 weeks. Anthropometric parameters were measured by trained nurses, and defecation characteristics, gastrointestinal symptoms, (serious) adverse events ((s)AEs), crying patterns and lifestyle behaviours were recorded by parents or guardians. Neurocognitive development was assessed by the Ages and Stages Questionnaires-3 (ASQ-3) before and after the intervention. The only difference between groups regarding defecation characteristics was a significant treatment × time effect on stool frequency (P=0.007), as the number of defecations was significantly higher in the probiotic group (around 1.2-1.3 times/day) than in the placebo group (around 1.0 times/day) in the later intervention period (P=0.035 at week 9; P=0.048 at week 10; P=0.026 at week 12). The use of L. paracasei N1115 also reduced the incidence rate of constipation (Incidence rate ratio (IRR): 0.120; 95% confidence interval (CI): 0.015, 0.967; P=0.046) and abdominal pain (IRR: 0.562; 95% CI: 0.358, 0.882; P=0.012). Changes in anthropometric parameters, including weight, height and head circumference, did not differ significantly between groups, nor did measures of crying, sleep, outdoor activity, temper, appetite or the ASQ-3 scores. No adverse events associated with consumption of the probiotic were reported. Thus, the administration of L. paracasei N1115 is safe and well-tolerated in caesarean-born children aged 6-24 months. Furthermore, it may ameliorate gastrointestinal function to some extent.

Online information in Spanish on probiotics, yoghurt, kefir, kombucha, fibre and prebiotics: an analysis of the quality of information and the certainty of the evidence supporting health claims

OBJECTIVE

To examine the certainty of the evidence supporting health claims about probiotics, yoghurt, kefir, kombucha, fibre and prebiotics, and to assess the quality of online information in Spanish.

DESIGN

Content analysis.

METHODS

We compiled a data set of 114 web pages by searching six popular search phrases in Spanish relating to probiotics, yoghurt, kefir, kombucha, fibre and prebiotics on Google.es and coded them for typology and health claims. We examined the certainty of the evidence for health claims from systematic reviews. Information quality was assessed according to 10 criteria, where a web page: mentions scientific publications and reports their conclusions; quantifies relative and absolute effects; acknowledges some limitations; discusses certainty of evidence; reports the potential harms, alternatives and costs; and does not argue based on personal experiences.

RESULTS

Gastrointestinal health (86.0%), general health (57.9%), cardiovascular health (53.5%) and immune system health (50.9%) were the most widely mentioned topics. Half of claims (52.6%, 70/133) were supported by evidence from systematic reviews. Probiotics had the highest number of claims supported by evidence and kombucha the lowest. The highest certainty was found for antibiotic-associated diarrhoea, necrotising enterocolitis and otitis (moderate) in probiotics and yoghurt, infectious diarrhoea and hepatic encephalopathy (moderate) in prebiotics, and cardiovascular health (high to moderate) and colorectal cancer (moderate) in fibre. On a scale of 0-10, the median information quality score for all web pages was 3. Only 18.4% reported study conclusions, 7.9% quantified the effects, 28.9% acknowledged some limitations in the research and 42.1% reported potential harms.

CONCLUSIONS

Most online health claims for dietary interventions intended for improving health through the gut microbiome are supported by low or very low certainty of evidence. Online information does not align with the evidence and is incomplete or unbalanced.

Probiotics for the Prevention of Antibiotic-Associated Diarrhea

Several communities have started using probiotic-rich fermented foods as therapeutic options with presumed medicinal powers. We now know the importance of microbiome balance and how probiotics can restore imbalances in the microbiome. Probiotics have been tested for a number of clinical uses such as the prevention of antibiotic-associated diarrhea (AAD), the treatment of various diseases such as H. pylori infection, irritable bowel disease, vaginitis, the prevention of allergies, and necrotizing enterocolitis in newborns. AAD has been the most indicated therapeutic use for probiotics. AAD is a common side effect of antibiotic usage, which affects up to 30% of patients. The hypothesis behind using probiotics for AAD is that they help normalize an unbalanced flora. There are many potential mechanisms by which probiotics support intestinal health such as (i) boosting immunity, (ii) increasing gut barrier integrity, (iii) producing antimicrobial substances, (iv) modulating the gut microbiome, (v) increasing water absorption, and (vi) decreasing opportunistic pathogens. Many randomized-controlled trials including the strain-specific trials that use Lactobacillus and Saccharomyces and meta-analyses have shown the benefits of probiotics in addressing AAD. Although adverse events have been reported for probiotics, these are broadly considered to be a safe and inexpensive preventative treatment option for AAD and other gastrointestinal disorders.

Effects of Probiotics on Allergic Rhinitis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

BACKGROUND

The prevalence of allergic rhinitis has been estimated to range from 10 to 30% in adults and up to 40% in children. Probiotics have been tested as for this condition, but no census on which probiotic types are most effective.

OBJECTIVE

Our aim of this study was to provide probiotic strain-specific evaluation for the treatment of allergic rhinitis.

METHODS

Databases (PubMed, Google Scholar, and ScienceDirect) were searched (from inception to October 2020) to identify randomized controlled trials (RCTs) of probiotic treatments in allergic rhinitis patients. A systematic review was done comparing types of reported outcomes, clinical and immunological parameters and safety data. A meta-analysis was done for probiotics with at least two RCTs per probiotic strain(s) and sharing a common outcome.

RESULTS

A total of 13 randomized, double-blind, placebo-controlled trials (N = 1591 participants) were included in the systematic review. Overall, 8 of 9 probiotic types alleviated at least one clinical symptom of allergic rhinitis. The meta-analysis results showed that, neither L. paracasei Lp33 (SMD = -1.61, 95% CI -4.67, 1.45) nor L. rhamnosus GG (SMD = -1.00, 95% CI -3.01, 1.00) had significant efficacy for reducing nasal symptom scores.

CONCLUSIONS

Our analysis showed probiotics produced a slight improvement in some clinical and immunological measurements on allergic rhinitis. Due to the diversity of outcome measurements and lack of sufficient trials for each probiotic strain, future trials are needed with similar study design and uniform outcomes to better compare the effect of probiotics on allergic rhinitis.

New compound probiotic beverage protects against antibiotic-associated diarrhea in mice by modulating the microbiota

Probiotics and their products are the classic way to treat and prevent gastrointestinal diseases. In this study, the authors designed new combinations and doses of probiotic beverages for antibiotic-associated diarrhea. Group S1 was different from the other groups, including Lactobacillus rhamnosus HN001, Lactobacillus acidophilus NCFM and Bifidobacterium lactis BI-07. Its inulin content was higher than those of the other groups. Mice were induced with a 16-day administration of triple antibiotics in advance for 2 weeks prior to antibiotic treatment. In the experiment, the treatment group returned to normal more quickly than the placebo group. In group S1, the relative abundance of the phylum Firmicutes and genus Lactobacillus increased, and the structure of the microbiota was the closest to normal among all groups. In conclusion, the combinations of probiotic beverages effectively caused structural recovery of the gut and fecal microbiota against antibiotic-associated diarrhea, and the S1 formula showed the best efficacy.

Genomic Characterization of Lactobacillus delbrueckii Strains with Probiotics Properties

Probiotics are health-beneficial microorganisms with mainly immunomodulatory and anti-inflammatory properties. Lactobacillus delbrueckii species is a common bacteria used in the dairy industry, and their benefits to hosting health have been reported. This study analyzed the core genome of nine strains of L. delbrueckii species with documented probiotic properties, focusing on genes related to their host health benefits. For this, a combined methodology including several software and databases (BPGA, SPAAN, BAGEL4, BioCyc, KEEG, and InterSPPI) was used to predict the most important characteristics related to L. delbrueckii strains probiose. Comparative genomics analyses revealed that L. delbrueckii probiotic strains shared essential genes related to acid and bile stress response and antimicrobial activity. Other standard features shared by these strains are surface layer proteins and extracellular proteins-encoding genes, with high adhesion profiles that interacted with human proteins of the inflammatory signaling pathways (TLR2/4-MAPK, TLR2/4-NF-κB, and NOD-like receptors). Among these, the PrtB serine protease appears to be a strong candidate responsible for the anti-inflammatory properties reported for these strains. Furthermore, genes with high proteolytic and metabolic activity able to produce beneficial metabolites, such as acetate, bioactive peptides, and B-complex vitamins were also identified. These findings suggest that these proteins can be essential in biological mechanisms related to probiotics’ beneficial effects of these strains in the host.

Progress in application of probiotics, prebiotics, and synbiotics in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common functional bowel disorder characterized by recurrent abdominal pain accompanied by changes in defecation frequency and/or stool characteristics. The global incidence of IBS is increasing year by year. Intestinal symptoms caused by IBS (such as constipation, diarrhea, abdominal pain, and abdominal distension) and accompanying changes in general nervous system function can significantly reduce patients' quality of life and work efficiency, and lead to high medical costs. Therefore, finding safe, effective, and economical treatments has become a hot research topic in recent years. Studies have shown that the intestinal flora of patients with IBS is different from that of healthy subjects, and regulating the intestinal flora can treat IBS. The purpose of this review is to summarize the application and recent progress of probiotics, prebiotics, and synbiotics in the treatment of IBS by regulating the intestinal flora.

Travellers' diarrhoea - prevention, trends and role of microbiome

OBJECTIVES

In this review, we present a contemporary look at the management of travellers' diarrhoea (TD), and we discuss the potential role of a microbiome as well as the administration of live microorganisms in order to prevent TD.

METHODS

We performed a comprehensive search using the PubMed and Web of Science databases for the period 2014-2021, looking for original and review articles on travellers' diarrhoea.

RESULTS

TD belongs among the most frequent illnesses experienced by travellers. For the most part, it is manifested as an acute yet self limiting condition, and only in a few cases proceeds to a prolonged form. Epidemiological analyses have shown that the majority of TD cases are caused by bacterial infections. In practice, pharmacological therapy is often used in the prevention and treatment of TD, since patients naturally seek preventive measures against the development of its severe course and its impact on planned activities. Bismuth salicylate is a strongly recommended TD prophylaxis but is not available on all European Union markets. Although the antibiotic prophylaxis is not generally recommended in guidelines, some antibiotic or chemotherapeutic agents are accessible over-the-counter in certain countries, and travellers are routinely encouraged to use them preventively. This routine can alter the microbiome of the traveller and promote the spread of drug resistant bacteria in their place of residence. Probiotic administration is considered safe, although the quality of evidence in favour of its prophylactic use in TD is currently low.

CONCLUSIONS

The challenge for public health authorities is to educate personnel that can directly influence the behaviour of travellers through safe and effective pharmacological alternatives to antibiotics. Manipulation of the gut microbiome using specific probiotic strains can represent a safe and promising intervention.

Safety Assessment of Lactiplantibacillus plantarum TWK10 Based on Whole-Genome Sequencing, Phenotypic, and Oral Toxicity Analysis

Lactiplantibacillus plantarum TWK10 (TWK10), isolated from Taiwanese pickled cabbage, has been demonstrated to exert beneficial probiotic effects in both mice and humans. Here, we comprehensively assessed the safety of TWK10 using both in vivo and in vitro approaches, including whole-genome sequence analysis, an assessment of hemolytic activity, and performing an antimicrobial susceptibility test, the Ames bacterial reverse mutation assay, the chromosomal aberration test, a rodent peripheral blood micronucleus test, and the 28-day subacute oral toxicity assay. The results showed that there was no significant increase in the incidence of reverse mutations or chromosomal aberrations following exposure to TWK10. Moreover, no significant changes were detected either in the number of reticulocytes or the incidence of micronuclei in ICR mice, and no subacute toxicity was recorded in SD rats at the oral TWK10 dosage of 2000 mg/kg body weight/day repeated for 28 days. Additionally, TWK10 exhibited no hemolytic activity and was susceptible to all the antibiotics tested, except kanamycin. However, no antimicrobial resistance genes, virulence factors, or genes involved in biogenic amine synthesis were found in the genome of TWK10. Our findings demonstrated that TWK10 has high potential of being safe for human consumption as a probiotic.

Evaluation of IR Biotyper for Lactiplantibacillus plantarum Typing and Its Application Potential in Probiotic Preliminary Screening

IR Biotyper (IRBT), which is a spectroscopic system for microorganism typing based on Fourier transform infrared (FTIR) technology, has been used to detect the spread of clones in clinical microbiology laboratories. However, the use of IRBT to detect probiotics has rarely been reported. Herein, we evaluated the discriminatory power of IRBT to type Lactiplantibacillus plantarum isolates at the strain level and explored its application potential in probiotic preliminary selection. Twenty Lactiplantibacillus isolates collected from pickled radishes during successive fermentation were used to test the robustness of IRBT at the strain level. IRBT was then compared with genotyping methods such as whole-genome sequencing (WGS), pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST) to evaluate its discrimination power. IRBT distributed the 20 isolates into five clusters, with L. argentoratensis isolate C7-83 being the most distant from the other isolates, which belonged to L. plantarum. IRBT showed good reproducibility, although deviation in the discriminative power of IRBT was found at the strain level across laboratories, probably due to technical variance. All examined methods allowed bacterial identification at the strain level, but IRBT had higher discriminatory power than MLST and was comparable to the WGS and PFGE. In the phenotypic comparison study, we observed that the clustering results of probiotic physiological attributes (e.g., sensitivity to acid and bile salts, hydrophobicity of the cell surface, and resistance to antibiotics) were consistent with the typing results of IRBT. Our results indicated that IRBT is a robust tool for L. plantarum strain typing that could improve the efficiency of probiotic identification and preliminary screening, and can potentially be applied in probiotic traceability and quality control.

Best Practices for Probiotic Research in Athletic and Physically Active Populations: Guidance for Future Randomized Controlled Trials

Probiotic supplementation, traditionally used for the prevention or treatment of a variety of disease indications, is now recognized in a variety of population groups including athletes and those physically active for improving general health and performance. However, experimental and clinical trials with probiotics commonly suffer from design flaws and different outcome measures, making comparison and synthesis of conclusions difficult. Here we review current randomized controlled trials (RCTs) using probiotics for performance improvement, prevention of common illnesses, or general health, in a specific target population (athletes and those physically active). Future RCTs should address the key elements of (1) properly defining and characterizing a probiotic intervention, (2) study design factors, (3) study population characteristics, and (4) outcome measures, that will allow valid conclusions to be drawn. Careful evaluation and implementation of these elements should yield improved trials, which will better facilitate the generation of evidence-based probiotic supplementation recommendations for athletes and physically active individuals.

In vitro Evaluation of the Anti-hypercholesterolemic Effect of Lactobacillus Isolates From Various Sources

The anti-hypercholesterolemic effect of 11 Lactobacillus isolates was investigated in vitro by measuring remaining cholesterol in growth media, growth ability in media supplemented with cholesterol, and BSH activity. Among the selected isolates, DLBSH104, DLBSH122, and DLBSK207 have demonstrated outstanding potential as cholesterol-lowering cultures. The three isolates showed high cholesterol removal by growing cells, whereas resting and dead cells showed less cholesterol removal. Furthermore, visualization of those isolates in growing and non-growing states by SEM showed the ability of DLBSH104 to attach cholesterol to their cell surface. In contrast, alteration of DLBSH122 and DLBSK207 cells did not involve surface attachment of cholesterol. Thus, the isolates’ ability to remove cholesterol is mainly attributed to the cells’ metabolically active state that assimilates and incorporates cholesterol into the cell membrane as reflected by a significantly higher cholesterol removal in a growing state than a non-growing state. Only in DLBSH104 did cholesterol removal also involve attachment on the cell surface. Moreover, DLBSH104 has beneficially affected the host cell by a significant reduction of NPC1L1 mRNA levels that are responsible for intestinal cholesterol absorption. In hepatic cells, cell-free supernatant (CFS) from DLBSH104 and DLBSK207 were able to reduce LDLR and HMGCR mRNA at the transcription level. To sum up, L. helveticus DLBSH104 and L. plantarum DLBSK207 are confirmed as isolates with an anti-hypercholesterolemic effect.

Probiotics in Critically Ill Patients: An Umbrella Review

Objectives

Data sources

Study selection

Data extraction

Data synthesis

Conclusion

How to cite this article

Effects of Probiotic Supplementation on Exercise with Predominance of Aerobic Metabolism in Trained Population: A Systematic Review, Meta-Analysis and Meta-Regression

The scientific literature about probiotic intake and its effect on sports performance is growing. Therefore, the main aim of this systematic review, meta-analysis and meta-regression was to review all information about the effects of probiotic supplementation on performance tests with predominance of aerobic metabolism in trained populations (athletes and/or Division I players and/or trained population: ≥8 h/week and/or ≥5 workouts/week). A structured search was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA®) statement and PICOS guidelines in PubMed/MEDLINE, Web of Science (WOS), and Scopus international databases from inception to 1 November 2021. Studies involving probiotic supplementation in trained population and execution of performance test with aerobic metabolism predominance (test lasted more than 5 min) were considered for inclusion. Fifteen articles were included in the final systematic review (in total, 388 participants were included). After 3 studies were removed due to a lack of data for the meta-analysis and meta-regression, 12 studies with 232 participants were involved. With the objective of assessing the risk of bias of included studies, Cochrane Collaboration Guidelines and the Physiotherapy Evidence Database (PEDro) scale were performed. For all included studies the following data was extracted: authors, year of publication, study design, the size of the sample, probiotic administration (dose and time), and characteristics of participants. The random effects model and pooled standardized mean differences (SMDs) were used according to Hedges’ g for the meta-analysis. In order to determine if dose and duration covariates could predict probiotic effects, a meta-regression was also conducted. Results showed a small positive and significant effect on the performance test with aerobic metabolic predominance (SMD = 0.29; CI = 0.08−0.50; p < 0.05). Moreover, the subgroup analysis displayed significant greater benefits when the dose was ≥30 × 109 colony forming units (CFU) (SMD, 0.47; CI, 0.05 to 0.89; p < 0.05), when supplementation duration was ≤4 weeks (SMD, 0.44; CI, 0.05 to 0.84; p < 0.05), when single strain probiotics were used (SMD, 0.33; CI, 0.06 to 0.60; p < 0.05), when participants were males (SMD, 0.30; CI, 0.04 to 0.56; p < 0.05), and when the test was performed to exhaustion (SMD, 0.45; CI, 0.05 to 0.48; p < 0.05). However, with references to the findings of the meta-regression, selected covariates did not predict probiotic effects in highly trained population. In summary, the current systematic review and meta-analysis supported the potential effects of probiotics supplementation to improve performance in a test in which aerobic metabolism is predominant in trained population. However, more research is needed to fully understand the mechanisms of action of this supplement.

Genome Sequence and Assessment of Safety and Potential Probiotic Traits of Lactobacillus johnsonii CNCM I-4884

The probiotic strain Lactobacillus johnsonii CNCM I-4884 exhibits anti-Giardia activity in vitro and in vivo in a murine model of giardiasis. The aim of this study was the identification and characterization of the probiotic potential of L. johnsonii CNCM I-4884, as well as its safety assessment. This strain was originally classified as Lactobacillus gasseri based on 16S gene sequence analysis. Whole genome sequencing led to a reclassification as L. johnsonii. A genome-wide search for biosynthetic pathways revealed a high degree of auxotrophy, balanced by large transport and catabolic systems. The strain also exhibits tolerance to low pH and bile salts and shows strong bile salt hydrolase (BSH) activity. Sequencing results revealed the absence of antimicrobial resistance genes and other virulence factors. Phenotypic tests confirm that the strain is susceptible to a panel of 8 antibiotics of both human and animal relevance. Altogether, the in silico and in vitro results confirm that L. johnsonii CNCM I-4884 is well adapted to the gastrointestinal environment and could be safely used in probiotic formulations.

Outlook on next-generation probiotics from the human gut

Probiotics currently available on the market generally belong to a narrow range of microbial species. However, recent studies about the importance of the gut microbial commensals on human health highlighted that the gut microbiome is an unexplored reservoir of potentially beneficial microbes. For this reason, academic and industrial research is focused on identifying and testing novel microbial strains of gut origin for the development of next-generation probiotics. Although several of these are promising for the prevention and treatment of many chronic diseases, studies on human subjects are still scarce and approval from regulatory agencies is, therefore, rare. In addition, some issues need to be overcome before implementing their wide application on the market, such as the best methods for cultivation and storage of these oxygen-sensitive taxa. This review summarizes the most recent evidence related to NGPs and provides an outlook to the main issues that still limit their wide employment.

Promising Indicators in Probiotic-recommendations in COVID-19 and its Accompanying Diseases

Scientific data suggests the possible beneficial role of probiotics in treatments for COVID-19, but the species/strains-specificity and disease-specificity of probiotics need high attention in choosing the appropriate probiotic in diseases, in particularly in the COVID-19. We hope this review will raise awareness of the COVID-19 probiotic recommendations, highlighting the latest scientific information about virus/hydrogen peroxide/probiotics and the importance of finding out of a specific “criterion” for the probiotics’ recommendation in this disease.

Immunomodulatory potential of four candidate probiotic Lactobacillus strains from plant and animal origin using comparative genomic analysis

Probiotic strains from different origins have shown promise in recent decades for their health benefits, for example in promoting and regulating the immune system. The immunomodulatory potential of four Lactobacillus strains from animal and plant origins was evaluated in this paper based on their genomic information. Comparative genomic analysis was performed through genome alignment, average nucleotide identity (ANI) analysis and gene mining for putative immunomodulatory genes. The genomes of the four Lactobacillus strains show relative similarities in multiple regions, as observed in the genome alignment. However, ANI analysis showed that L. mucosae LM1 and L. fermentum SK152 are the most similar when considering their nucleotide sequences alone. Gene mining of putative immunomodulatory genes studied from L. plantarum WCFS1 yielded multiple results in the four potential probiotic strains, with L. plantarum SK151 showing the largest number of genes at around 74 hits, followed by L. johnsonii PF01 at 41 genes when adjusted for matches with at least 30 % identity. Looking at the immunomodulatory genes in each strain, L. plantarum SK151 and L. johnsonii PF01 may have wider activity, covering both immune activation and immune suppression, as compared to L. mucosae LM1 and L. fermentum SK152, which could be more effective in activating immune cells and the pro-inflammatory cascade rather than suppressing it. The similarities and differences between the four Lactobacillus species showed that there is no definitive trend based on the origin of isolation alone. Moreover, higher percentage identities between genomes do not directly correlate with higher similarities in potential activity, such as in immunomodulation. The immunomodulatory function of each of the four Lactobacillus strains should be observed and verified experimentally in the future, since some the activity of some genes may be strain-specific, which would not be identified through comparative genomics alone.

Locked Nucleic Acid Hydrolysis Probes for the Specific Identification of Probiotic Strains Bifidobacterium animalis subsp. lactis DSM 15954 and Bi-07™

Probiotic health benefits are now well-recognized to be strain specific. Probiotic strain characterization and identification is thus important in clinical research and in the probiotic industry. This is becoming especially important with reports of probiotic products failing to meet the declared strain content, potentially compromising their efficacy. Availability of reliable identification methods is essential for strain authentication during discovery, evaluation and commercialization of a probiotic strain. This study aims to develop identification methods for strains Bifidobacterium animalis subsp. lactis DSM 15954 and Bi-07 (Bi-07™) based on real-time PCR, targeting single nucleotide polymorphisms (SNPs). The SNPs were targeted by PCR assays with locked nucleic acid (LNA) probes, which is a novel application in probiotic identification. The assays were then validated following the guidelines for validating qualitative real-time PCR assays. Each assay was evaluated for specificity against 22 non-target strains including closely related Bifidobacterium animalis subsp. lactis strains and were found to achieve 100% true positive and 0% false positive rates. To determine reaction sensitivity and efficiency, three standard curves were established for each strain. Reaction efficiency values were 86, 91, and 90% (R square values > 0.99), and 87, 84, and 86% (R square values > 0.98) for B. animalis subsp. lactis DSM 15954 and Bi-07 assays, respectively. The limit of detection (LOD) was 5.0 picograms and 0.5 picograms of DNA for DSM 15954 and Bi-07 assays, respectively. Each assay was evaluated for accuracy using five samples tested at three different DNA concentrations and both assays proved to be highly repeatable and reproducible. Standard deviation of Cq values between two replicates was always below 1.38 and below 1.68 for DSM 15954 and Bi-07 assays, respectively. The assays proved to be applicable to mono-strain and multi-strain samples as well as for samples in various matrices of foods or dietary supplement ingredients. Overall, the methods demonstrated high specificity, sensitivity, efficiency and precision and broad applicability to sample, matrix and machine types. These methods facilitate strain level identification of the highly monophyletic strains B. animalis subsp. lactis DSM 15954 and Bi-07 to ensure probiotic efficacy and provide a strategy to identify other closely related probiotics organisms.

Vitreoscilla filiformis Extract for Topical Skin Care: A Review

The term probiotic has been defined by experts as live microorganisms, which when administered in adequate amounts, confer a health benefit on the host. Probiotics are, thus, by definition, live microorganisms, and the viability of probiotics is a prerequisite for certain benefits, such as the release of metabolites at the site or adhesion properties, for example. However, some semi-active or non-replicative bacterial preparations may retain a similar activity to the live forms. On cosmetic, lysates or fractions are generally used. Topically applied Vitreoscilla filiformis extract has shown to have some similar biological activity of probiotics in the gut, for example, regulating immunity by optimisation of regulatory cell function, protecting against infection, and helping skin barrier function for better recovery and resistance. Due to their mode of action and efficacy, V. filiformis extract (lysate including membrane and cytosol) may be considered as non-replicative probiotic fractions, and this review article presents all its properties.

Probiotics to HIV-Infected Immunological Nonresponders: Altered Mucosal Immunity and Microbial Diversity Restricted to Ileum

BACKGROUND

HIV-infected immunological nonresponders (INRs) have increased risk of non-AIDS morbidity and compromised gut barrier immunity. Probiotics are widely used to improve health. We assessed the effects of probiotics in INRs with a comprehensive analysis of gut immunity and microbiome in terminal ileum and sigmoid colon.

METHODS

The study involved clinical intervention with five-strain probiotic capsules (1.2 × 1010 CFUs/d) for 8 weeks in 20 INRs with CD4+ T-cell counts <400 cells/µL and plasma HIV RNA <50 copies/mL for more than 3.5 years. Colonoscopy with sampling of gut biopsies from terminal ileum and sigmoid colon and fecal and blood sampling were performed before and after the intervention. Flow cytometry (cytokine production, immune activation, and exhaustion), ELISA (inflammation, microbial translocation, and enterocyte damage), and 16S rRNA sequencing analyses were applied.

RESULTS

In the terminal ileum, increased alpha diversity, increased abundance of Bifidobacterium sp., and decreased frequencies of IL-22+ CD4+ T cells were observed. The increased abundance of Bifidobacterium sp. in the terminal ileum correlated with increased fraction of CD4+ T cells in the same compartment (r = 0.54, P = 0.05) and increased CD4/CD8 ratio in peripheral blood (r = 0.49, P = 0.05). There were no corresponding changes in the sigmoid colon and no changes in fecal microbiome. Probiotic intervention did not affect peripheral blood CD4 count, viral load, or soluble markers of inflammation and microbial translocation.

CONCLUSIONS

Probiotics induced segment-specific changes in the terminal ileum but did not affect systemic CD4 counts in INRs. Further clinical studies are warranted to recommend probiotics to INRs.

Multi-targeted properties of the probiotic saccharomyces cerevisiae CNCM I-3856 against enterotoxigenic escherichia coli (ETEC) H10407 pathogenesis across human gut models

Enterotoxigenic Escherichia coli (ETEC) is one of the most common causes of acute traveler's diarrhea. Adhesins and enterotoxins constitute the major ETEC virulence traits. With the dramatic increase in antibiotic resistance, probiotics are considered a wholesome alternative to prevent or treat ETEC infections. Here, we examined the antimicrobial properties of the probiotic Saccharomyces cerevisiae CNCM I-3856 against ETEC H10407 pathogenesis upon co-administration in the TNO gastrointestinal Model (TIM-1), simulating the physicochemical and enzymatic conditions of the human upper digestive tract and preventive treatment in the Mucosal Simulator of the Human Intestinal Microbial Ecosystem (M-SHIME), integrating microbial populations of the ileum and ascending colon. Interindividual variability was assessed by separate M-SHIME experiments with microbiota from six human individuals. The probiotic did not affect ETEC survival along the digestive tract. However, ETEC pathogenicity was significantly reduced: enterotoxin encoding virulence genes were repressed, especially in the TIM-1 system, and a lower enterotoxin production was noted. M-SHIME experiments revealed that 18-days probiotic treatment stimulate the growth of Bifidobacterium and Lactobacillus in different gut regions (mucosal and luminal, ileum and ascending colon) while a stronger metabolic activity was noted in terms of short-chain fatty acids (acetate, propionate, and butyrate) and ethanol production. Moreover, the probiotic pre-treated microbiota displayed a higher robustness in composition following ETEC challenge compared to the control condition. We thus demonstrated the multi-inhibitory properties of the probiotic S. cerevisiae CNCM I-3856 against ETEC in the overall simulated human digestive tract, regardless of the inherent variability across individuals in the M-SHIME.

Probiotics and Vitamin D/Vitamin D Receptor Pathway Interaction: Potential Therapeutic Implications in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) are chronic conditions of unknown etiology and immunomediated pathogenesis. In the last years, the comprehension of the complex mechanisms involved in the intestinal mucosal homeostasis, and the analysis of the alterations potentially leading to inflammatory pathologic states, has consistently increased. Specifically, the extraordinary impulse in the field of research of the intestinal microbiome has opened the door to the investigation of possible novel approaches to the diagnosis, management and therapeutic applications in IBD. In line with that, administration of probiotic bacteria has been intensely evaluated, leading to much more exciting results in experimental models than in clinical practice. Considering the consistent heterogeneity of the available studies on probiotics, the increased knowledge of the properties of the single bacterial species would ideally lead to unravel potential mechanisms of action that may bring therapeutic applications in specific pathologic condition. Among the relevant molecular pathways for mucosal homeostasis maintenance, the vitamin D/vitamin D receptor (VDR) pathway has been intensely studied in the very last years. In fact, besides osteometabolic functions, the vitamin D exerts important homeostatic effects in the organism at multiple levels, such as immunomodulation, inflammation control, and microbiota regulation, which are likely to play a relevant role in intestinal mucosa protection. In the present review, recent findings about probiotic applications in IBD and mechanisms of action linking vitamin D/VDR pathway to IBD are reported. Available evidence for probiotic effect on vitamin D/VDR are reviewed and potential future application in IBD patients are discussed. At present, many aspects of IBD pathogenesis are still obscure, and current therapeutic options for IBD treatment are at best suboptimal. The increasing comprehension of the different pathways involved in IBD pathogenesis will lead to novel findings ideally leading to potential clinical applications. Microbiota manipulation and vitamin/VDR pathway appear a promising field for future research and therapeutic developments.

Probiotics Evaluation in Oncological Surgery: A Systematic Review of 36 Randomized Controlled Trials Assessing 21 Diverse Formulations

BACKGROUND

Objectives were to evaluate probiotics safety and efficacy in oncological surgery.

METHODS

Systematic review methodology guided by Cochrane, PRISMA, SWiM, and CIOMS. Protocol registered on PROSPERO (CRD42018086168).

RESULTS

36 RCTs (on 3305 participants) and 6 nonrandomized/observational studies were included, mainly on digestive system cancers. There was evidence of a beneficial effect on preventing infections, with 70% of RCTs' (21/30) direction of effect favoring probiotics. However, five RCTs (17%) favored controls for infections, including one trial with RR 1.57 (95% CI: 0.79, 3.12). One RCT that changed (balanced) its antibiotics protocol after enrolling some participants had mortality risk RR 3.55 (95% CI: 0.77, 16.47; 7/64 vs. 2/65 deaths). The RCT identified with the most promising results overall administered an oral formulation of Lactobacillus acidophilus LA-5 + Lactobacillus plantarum + Bifidobacterium lactis BB-12 + Saccharomyces boulardii. Methodological quality appraisals revealed an overall substantial risk-of-bias, with only five RCTs judged as low risk-of-bias.

CONCLUSIONS

This large evidence synthesis found encouraging results from most formulations, though this was contrasted by potential harms from a few others, thus validating the literature that "probiotics" are not homogeneous microorganisms. Given microbiome developments and infections morbidity, further high-quality research is warranted using those promising probiotics identified herein.

Probiotics and synbiotics show clinical efficacy in treating gestational diabetes mellitus: A meta-analysis

BACKGROUND

This study performed a systematic and meta-analysis of randomized controlled trials (RCTs) to explore the efficacy of probiotic- and symbiotic-based supplements in the treatment of gestational diabetes mellitus (GDM).

METHODS

We performed a meta-analysis to evaluate the efficacy of probiotics/synbiotics in GDM treatment, following a systematic search in Web of Science, PubMed, Cochrane Library, and EBSCO databases for articles published up to July 2020.

RESULTS

In total, 12 RCTs comprising 894 participants, were analyzed. Compared to the placebo, patients administered with probiotic and synbiotic supplements benefited more with regards to glucose and lipid metabolism as well as anti-inflammation and antioxidant capacity including insulin of change (WMD: 3.57, 95%CI: -5.26, -1.88), very-low-density lipoprotein (VLDL) (WMD: -5.03, 95%CI: -8.26, -1.79), nitric oxide (NO) at the end of trial (WMD: 2.31, 95%CI: 0.91, 3.70), total antioxidant capacity (TAC) at the end of trial (SMD: 0.74, 95%CI: 0.21, 1.27), high-sensitivity C-reactive protein (hsCRP) at the end of trial (SMD: -1.23, 95%CI: -1.97, -0.49). Besides, probiotic and synbiotic supplements improved outcomes on fetal hyperbilirubinemia risk (RR: 0.26, 95%CI: 0.12, 0.55), fetal macrosomia risk (RR: 0.47, 95%CI: 0.27, 0.83) and newborn weight (SMD: -0.29, 95%CI: -0.50, -0.09).

CONCLUSIONS

Findings from this work demonstrate that probiotic/symbiotic-based interventions improve glucose and lipid metabolism, anti-inflammatory and antioxidant ability in diet-controlled GDM patients, and exert beneficial outcomes on fetal hyperbilirubinemia, fetal macrosomia, and newborn weight.

Lactobacillus rhamnosus Strain LRH05 Intervention Ameliorated Body Weight Gain and Adipose Inflammation via Modulating the Gut Microbiota in High-Fat Diet-Induced Obese Mice

SCOPE

This study aims to investigate the underlying mechanism of a specific probiotic strain on suppression of adipogenesis and inflammatory response in white adipose tissue (WAT) of high-fat diet (HFD)-fed mice.

METHODS AND RESULTS

Eight strains are screened in vitro for candidates of potential probiotics. Lactobacillus rhamnosus LRH05 (LRH05) and Lactobacillus reuteri LR47 (LR47) are screened out with lower triglyceride expression in vitro. The mice are fed a control diet (CD), HFD, or HFD supplemented with a dose of LRH05 or LR47 at 10⁹ CFU per mouse per day for 10 weeks (n = 8), respectively. The results demonstrate that LRH05, but not LR47, significantly reduce body weight gain and the weight of WAT, as well as improve hepatic steatosis and glucose intolerance. LRH05 regulates the Mogat1, Igf-1, Mcp-1, and F4/80 mRNA expression and decreases macrophage infiltration in WAT. LRH05 shows an increase in butyric and propionic acid-producing bacteria, including Lachnoclostridium, Romboutsia, and Fusobacterium that is coincident with the increased fecal propionic acid and butyric acid levels.

CONCLUSION

LRH05 shows a strain-specific effect on ameliorating the pro-inflammatory process by reducing inflammatory macrophage infiltration and the expression of inflammation-related genes in mice. Thus, LRH05 can be considered a potential probiotic strain to prevent obesity.

Development of a Probiotics Practice E-Reference Database for Health Care Professionals

PURPOSE

Currently available references provide evidence on the efficacy of probiotics strains but exclude product-specific information, making it challenging for health care professionals (HCPs) to provide consumers with suitable recommendations on probiotics. An online probiotics e-reference database was developed to assist HCPs in delivering evidence-based recommendations on probiotics to consumers. The usability and applicability of the database in health care practice were evaluated.

METHODS

Information on the efficacy of probiotics and probiotic products was collated using a PubMed literature search, and from local pharmacies and online supplement stores. A web database was compiled using various programming scripts and uploaded onto a web server. The database was beta-tested using an online self-administered questionnaire for community-based pharmacists, and responses were analyzed using descriptive statistics.

FINDINGS

The database comprised 584 clinical study excerpts, 449 probiotic products, and 1879 unique product-study links. Users can search for suitable probiotics based on their indication profile or for a specific probiotic product. Information provided includes the probiotic constituents, dosage regimen, and indications of the product, with supporting clinical evidence. Overall, all participants of the beta-test indicated that they were satisfied with the database and were willing to use it again (both, 13 participants [100%]). In addition, all participants indicated that they found the database intuitive to use and smooth functioning, without inconsistencies (both, 13 [100%]). The majority also indicated that they found the information provided to be clear, comprehensive, and useful in health care practice (12 [92.3%] each).

IMPLICATIONS

The probiotics e-reference database is an integrated resource that is user-friendly, and provides HCPs with ready access to clear and comprehensive information on probiotic products and clinical studies, so that HCPs can provide consumers with relevant and evidence-based recommendations on probiotics.

Strain-specific and outcome-specific efficacy of probiotics for the treatment of irritable bowel syndrome: A systematic review and meta-analysis

BACKGROUND

Consistent guidance for choosing an appropriate probiotic for the treatment of irritable bowel syndrome is lacking.

METHODS

Literature databases searched included: PubMed, Google Scholar and NIH registry of clinical trials from inception to June 2021. Inclusion criteria: randomized controlled trials (RCTs) enrolling adult or pediatric IBS patients comparing probiotics against controls and ≥ 2 RCTs with common IBS outcome measures within each type of probiotic. Five common measures of IBS symptoms (changes in global Irritable Bowel Syndrome Severity Scoring System or IBS-SSS scores, frequency of global responders, changes in bloating or abdominal pain scores and frequency of abdominal pain relief) were used. This study was registered at Prospero (#CRD42018109169).

FINDINGS

We screened 521 studies and included 42 randomized controlled trials (45 treatment arms, N = 3856). Four probiotics demonstrated significant reduction in abdominal pain relief: B. coagulans MTCC5260 (RR= 4.9, 95% C.I. 3.3, 7.3), L. plantarum 299v (RR= 4.6, 95% CI 1.9, 11.0), S. boulardii CNCM I-745 (RR= 1.5, 95% C.I. 1.1, 2.1) and S. cerevisiae CNCM I-3856 (RR= 1.3, 95% C.I. 1.04, 1.6). Mild-moderate adverse events were reported in 51% of the trials, none were more associated with the probiotic compared to controls.

INTERPRETATION

Although the analysis of probiotic efficacy was limited by the diversity of IBS outcomes used in trials and lack of confirmatory trials for some strains, six single-strain probiotics and three different types of probiotic mixtures showed significant efficacy for at least one IBS outcome measure. These results might be relevant to clinical practice and policy.

Functional fermented meat products with probiotics-A review

Fermentation has been an important strategy in the preservation of foods. The use of starter cultures with probiotic activity has gained the attention of researchers to produce functional fermented meat products. This review aims to overview the main strengths, weakness, opportunities and threats of fermented meat products with probiotics. Fermented meat products can be considered as a relevant matrix for the delivery of probiotics with potential health benefits. Moreover, fermented meat products produced by traditional methods are sources of probiotics that can be explored in the production of functional meat products. However, some barriers are limit the progression with these products: the complex selection process to obtain new and tailored probiotic strains, the current perception of healthiness associated with meat and meat products, and the limited application of probiotic to fermented sausages. Promising opportunities to improve the value of functional fermented meat products have been developed by exploring new meat products as functional fermented foods, improving the protection of probiotics with microencapsulation and improving the quality of meat product (reducing nitrate and nitrate salts, adding dietary fibre, and exploring the inherent antioxidant and cardioprotective activity of meat products). Attention to potential threats is also indicated such as the unclear future changes in meat and meat products consumption due to changes in consumer preferences and the presence of competitors (dairy, fruit and vegetable-based products, for instance) in more advanced stages of development and commercialization. SIGNIFICANCE AND IMPACT OF STUDY: This review provides an overview of the Strengths, Weakness, Opportunities and Threats related to the development of functional fermented meat products with probiotics. Internal and external factors that explain the current scenario and strategies to advance the production are highlighted.

High association of COVID-19 severity with poor gut health score in Lebanese patients

Background

Coronavirus disease 2019 (COVID-19) has affected millions of lives globally. However, the disease has presented more extreme challenges for developing countries that are experiencing economic crises. Studies on COVID-19 symptoms and gut health are scarce and have not fully analyzed possible associations between gut health and disease pathophysiology. Therefore, this study aimed to demonstrate a potential association between gut health and COVID-19 severity in the Lebanese community, which has been experiencing a severe economic crisis.

Methods

This cross-sectional study investigated SARS-CoV-2 PCR-positive Lebanese patients. Participants were interviewed and gut health, COVID-19 symptoms, and different metrics were analyzed using simple and multiple logistic regression models.

Results

Analysis of the data showed that 25% of participants were asymptomatic, while an equal proportion experienced severe symptoms, including dyspnea (22.7%), oxygen need (7.5%), and hospitalization (3.1%). The mean age of the participants was 38.3 ±0.8 years, and the majority were males (63.9%), married (68.2%), and currently employed (66.7%). A negative correlation was found between gut health score and COVID-19 symptoms (Kendall’s tau-b = -0.153, P = 0.004); indicating that low gut health was associated with more severe COVID-19 cases. Additionally, participants who reported unhealthy food intake were more likely to experience severe symptoms (Kendall’s tau-b = 0.118, P = 0.049). When all items were taken into consideration, multiple ordinal logistic regression models showed a significant association between COVID-19 symptoms and each of the following variables: working status, flu-like illness episodes, and gut health score. COVID-19 severe symptoms were more common among patients having poor gut health scores (OR:1.31, 95%CI:1.07–1.61; P = 0.008), experiencing more than one episode of flu-like illness per year (OR:2.85, 95%CI:1.58–5.15; P = 0.001), and owning a job (OR:2.00, 95%CI:1.1–3.65; P = 0.023).

Conclusions

To our knowledge, this is the first study that showed the impact of gut health and exposure to respiratory viruses on COVID-19 severity in Lebanon. These findings can facilitate combating the pandemic in Lebanon.

The characteristics of intestinal flora in overweight pregnant women and the correlation with gestational diabetes mellitus

OBJECTIVE

To investigate the characteristics of intestinal flora in overweight pregnant women and the correlation with gestational diabetes mellitus (GDM).

METHODS

A total of 122 women were enrolled and divided into four groups according to their pre-pregnancy BMI and the presence of GDM: group 1 (n = 71) with a BMI <24 kg/m2, without GDM; group 2 (n = 27) with a BMI <24 kg/m2, with GDM; group 3 (n = 17) with a BMI ≥24 kg/m2, without GDM; and group 4 (n = 7) with a BMI ≥24 kg/m2 with GDM. Feces were collected on the day that the oral glucose tolerance test was conducted. The V3-V4 variable region of 16S rRNA was sequenced using the Illumina Hiseq 2500 platform, and a bioinformatics analysis was conducted.

RESULTS

There were differences between the four groups in the composition of intestinal flora, and it was significantly different in group 4 than in the other three groups. Firmicutes accounted for 36.4% of the intestinal flora in this group, the lowest among the four groups, while Bacteroidetes accounted for 50.1%, the highest among the four groups, making ratio of these two bacteria approximately 3:5, while in the other three groups, this ratio was reversed. In women with a BMI <24 kg/m2, the insulin resistance index (homeostatic model assessment for insulin resistance (HOMA-IR)) in pregnant women with GDM was higher than in those without (P3 = 0.026).

CONCLUSION

The composition of the intestinal flora of pregnant women who were overweight or obese before pregnancy and suffered from GDM was significantly different than women who were not overweight or did not suffer from GDM.

Probiotic lactobacilli in formulas and hygiene products for the health of the urogenital tract

Lactobacilli are the predominant microorganisms of the healthy human vagina. A novel alternative for the prevention and treatment of female urogenital tract infections (UGTI) is the inclusion of these microorganisms as active pharmaceutical ingredients in probiotic formulas, and more recently in female hygienic products. Probiotics are defined as “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.” A list of requirements must be considered during the development of probiotic product/formula for the female urogenital tract (UGT). This review aims to resume the requirements, probiotic characteristics, and clinical trial applied to determine the effect of probiotic and potentially probiotic strains on different woman’s physiological and pathological conditions, and in preterm birth prevention. A revision of female hygienic products available in the world market is included, together with novel studies applying nanotechnology for Lactobacillus incorporation in hygienic products. Further studies and well‐designed clinical trials are urgently required to complement the current knowledge and applications of probiotics in the female UGT. The use of probiotic formulas and products will improve and restore the ecological equilibrium of the UGT microbiome to prevent and treat UGTI in women under different conditions.

Untargeted LC-QTOF-MS/MS based metabolomics approach for revealing bioactive components in probiotic fermented coffee brews

Amidst trends in non-dairy probiotic foods and functional coffees, we recently developed a fermented coffee brew containing high live counts of the probiotics Lacticaseibacillus rhamnosus GG and Saccharomyces boulardii CNCM-I745. However, probiotic fermentation did not alter levels of principal coffee bioactive components based on targeted analyses. Here, to provide therapeutic justification compared to other non-fermented coffee brews, we aimed to discover postbiotics in coffee brews fermented with L. rhamnosus GG and/or S. boulardii CNCM-I745. By using an untargeted LC-QTOF-MS/MS based metabolomics approach coupled with validated multivariate analyses, 37 differential metabolites between fermentation treatments were putatively annotated. These include the production of postbiotics such as 2-isopropylmalate by S. boulardii CNCM-I745, and aromatic amino acid catabolites (indole-3-lactate, p-hydroxyphenyllactate, 3-phenyllactate), and hydroxydodecanoic acid by L. rhamnosus GG. Overall, LC-QTOF based untargeted metabolomics can be an effective approach to uncover postbiotics, which may substantiate additional potential functionalities of probiotic fermented foods compared to their non-fermented counterparts.

In vitro Inhibition of respiratory pathogens by lactobacillus and alpha haemolytic streptococci from Aboriginal and Torres Strait Islander children

AIMS

To explore the in vitro ability of alpha haemolytic streptococcus (AHS) and lactobacilli (LBs), from Indigenous Australian children, to inhibit the growth of respiratory pathogens (Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis), also from Indigenous Australian children.

METHODS AND RESULTS

The bacterial interference of 91 isolates, from Indigenous Australian children both with and without otitis media (OM) or rhinorrhoea, was investigated using agar overlay and cell-free supernatant. Promising isolates underwent whole genome sequencing to investigate upper respiratory tract tropism, antibiotic resistance and virulence. Antibiotic susceptibility was examined for ampicillin, amoxicillin +clavulanic acid and azithromycin. Differences in the strength of bacterial inferences in relation to OM was examined using a case series of three healthy and three children with OM. LBs readily inhibited the growth of pathogens. AHS were less effective, although several isolates inhibited S. pneumoniae. One L. rhamnosus had genes coding for pili to adhere to epithelial cells. We detected antibiotic resistance genes coding for antibiotic efflux pump and ribosomal protection protein. LBs were susceptible to antimicrobials in vitro. Screening for virulence detected genes encoding for two putative capsule proteins. Healthy children had AHS and LB that were more potent inhibitors of respiratory pathogens in vitro than children with OM.

CONCLUSIONS

L. rhamnosus from remote Indigenous Australian children are potent inhibitors of respiratory pathogens in vitro.

SIGNIFICANCE AND IMPACT OF STUDY

Respiratory/ear disease are endemic in Indigenous Australians. There is an urgent call for more effective treatment/prevention; beneficial microbes have not been explored. L. rhamnosus investigated in this study are potent inhibitors of respiratory pathogens in vitro and require further investigation.

Bifidobacteria Strain Typing by Fourier Transform Infrared Spectroscopy

Fourier transform infrared (FTIR) spectroscopy, a technology traditionally used in chemistry to determine the molecular composition of a wide range of sample types, has gained growing interest in microbial typing. It is based on the different vibrational modes of the covalent bonds between atoms of a given sample, as bacterial cells, induced by the absorption of infrared radiation. This technique has been largely used for the study of pathogenic species, especially in the clinical field, and has been proposed also for the typing at different subspecies levels. The high throughput, speed, low cost, and simplicity make FTIR spectroscopy an attractive technique also for industrial applications, in particular, for probiotics. The aim of this study was to compare FTIR spectroscopy with established genotyping methods, pulsed-field gel electrophoresis (PFGE), whole-genome sequencing (WGS), and multilocus sequence typing (MLST), in order to highlight the FTIR spectroscopy potential discriminatory power at strain level. Our study focused on bifidobacteria, an important group of intestinal commensals generally recognized as probiotics. For their properties in promoting and maintaining health, bifidobacteria are largely marketed by the pharmaceutical, food, and dairy industries. Strains belonging to Bifidobacterium longum subsp. longum and Bifidobacterium animalis subsp. lactis were taken into consideration together with some additional type strains. For B. longum subsp. longum, it was possible to discriminate the strains with all the methods used. Although two isolates were shown to be strictly phylogenetically related, constituting a unique cluster, based on PFGE, WGS, and MLST, no clustering was observed with FTIR. For B. animalis subsp. lactis group, PFGE, WGS, and MLST were non-discriminatory, and only one strain was easily distinguished. On the other hand, FTIR discriminated all the isolates one by one, and no clustering was observed. According to these results, FTIR analysis is not only equivalent to PFGE, WGS, and MLST, but also for some strains, in particular, for B. animalis subsp. lactis group, more informative, being able to differentiate strains not discernible with the other two methods based on phenotypic variations likely deriving from certain genetic changes. Fourier transform infrared spectroscopy has highlighted the possibility of using the cell surface as a kind of barcode making tracing strains possible, representing an important aspect in probiotic applications. Furthermore, this work constitutes the first investigation on bifidobacterial strain typing using FTIR spectroscopy.

In Silico Prediction of Novel Probiotic Species Limiting Pathogenic Vibrio Growth Using Constraint-Based Genome Scale Metabolic Modeling

The prevalence of bacterial diseases and the application of probiotics to prevent them is a common practice in shrimp aquaculture. A wide range of bacterial species/strains is utilized in probiotic formulations, with proven beneficial effects. However, knowledge of their role in inhibiting the growth of a specific pathogen is restricted. In this study, we employed constraint-based genome-scale metabolic modeling approach to screen and identify the beneficial bacteria capable of limiting the growth of V. harveyi, a common pathogen in shrimp culture. Genome-scale models were built for 194 species (including strains from the genera Bacillus, Lactobacillus, and Lactococcus and the pathogenic strain V. harveyi) to explore the metabolic potential of these strains under different nutrient conditions in a consortium. In silico-based phenotypic analysis on 193 paired models predicted six candidate strains with growth enhancement and pathogen suppression. Growth simulations reveal that mannitol and glucoronate environments mediate parasitic interactions in a pairwise community. Furthermore, in a mannitol environment, the shortlisted six strains were purely metabolite consumers without donating metabolites to V. harveyi. The production of acetate by the screened species in a paired community suggests the natural metabolic end product's role in limiting pathogen survival. Our study employing in silico approach successfully predicted three novel candidate strains for probiotic applications, namely, Bacillus sp 1 (identified as B. licheniformis in this study), Bacillus weihaiensis Alg07, and Lactobacillus lindneri TMW 1.1993. The study is the first to apply genomic-scale metabolic models for aquaculture applications to detect bacterial species limiting Vibrio harveyi growth.

Phenotypic Traits and Immunomodulatory Properties of Leuconostoc carnosum Isolated From Meat Products

Twelve strains of Leuconostoc carnosum from meat products were investigated in terms of biochemical, physiological, and functional properties. The spectrum of sugars fermented by L. carnosum strains was limited to few mono- and disaccharides, consistently with the natural habitats of the species, including meat and fermented vegetables. The strains were able to grow from 4 to 37°C with an optimum of approximately 32.5°C. The ability to grow at temperatures compatible with refrigeration and in presence of up to 60 g/L NaCl explains the high loads of L. carnosum frequently described in many meat-based products. Six strains produced exopolysaccharides, causing a ropy phenotype of colonies, according to the potential involvement on L. carnosum in the appearance of slime in packed meat products. On the other side, the study provides evidence of a potential protective role of L. carnosum WC0321 and L. carnosum WC0323 against Listeria monocytogenes, consistently with the presence in these strains of the genes encoding leucocin B. Some meat-based products intended to be consumed without cooking may harbor up to 10⁸ CFU/g of L. carnosum; therefore, we investigated the potential impact of this load on health. No strains survived the treatment with simulated gastric juice. Three selected strains were challenged for the capability to colonize a mouse model and their immunomodulatory properties were investigated. The strains did not colonize the intestine of mice during 10 days of daily dietary administration. Intriguingly, despite the loss of viability during the gastrointestinal transit, the strains exhibited different immunomodulatory effect on the maturation of dendritic cells in vivo, the extent of which correlated to the production of exopolysaccharides. The ability to stimulate the mucosal associated immune system in such probiotic-like manner, the general absence of antibiotic resistance genes, and the lack of the biosynthetic pathways for biogenic amines should reassure on the safety of this species, with potential for exploitation of selected starters.

Effects of Bifidobacterium Lactis BS01 and Lactobacillus Acidophilus LA02 on cognitive functioning in healthy women

A growing body of research studies the relationship between probiotic bacteria in the gut and the host organism, including the impact on cognitive functioning. Data from human studies are scarce; however, recent studies point toward the beneficial role of probiotics for cognitive functioning. One of the mechanisms involved in this relationship is the probiotic's ability to influence inflammation and immune response. The aim of this initial study was to investigate the effects of probiotic supplementation with Bifidobacterium Lactis BS01 and Lactobacillus Acidophilus LA02 on cognitive functioning in healthy, young adult females. A total of 53 participants aged 19-31 were enrolled, and 38 completed the trial. A 6-week probiotic or placebo treatment was conducted. Five measures of cognitive functioning were applied pre- and post-treatment. Both groups showed general improvement at the second assessment. Contrary to our hypothesis, the placebo group improved slightly, but significantly, in four out of five measures of cognitive functioning, with the exception of the Wisconsin Card Sorting Test (WCST). The supplementation group improved significantly in two measures of the WCST, compared to the placebo group. Similar results have been previously reported. Probiotic supplementation, while not harmful, might not be beneficial for cognition in the healthy population, or at least not universally.

Probiotics in the Management of Gingivitis and Periodontitis. A Review

In the management of intestinal health problems, the targeted use of probiotic microorganisms is a common therapeutic measure with a long-standing tradition. In clinical dentistry however, probiotics-based therapy is still a rather new and developing field, whose usefulness for the control of gingivitis and periodontitis has been questioned by recent meta-analyses and systematic reviews. The purpose of the subsequent descriptive review is to provide an introduction to the concept of probiotic microorganisms and their multifaceted health-promoting interactions with the human host and microbial competitors, followed by a detailed comparison of the results of available controlled clinical trials assessing the use of probiotics in the control of gingival and periodontal inflammations. It aims at contributing to a deeper understanding of the unique capabilities of probiotics to resolve chronic plaque-induced inflammation even in the absence of mechanical plaque control and will discuss how possible misconceptions about the rationale for using probiotics may have led to the present controversies about their usefulness as a therapeutic option.

Lactiplantibacillus plantarum 299v (LP299V®): three decades of research

This review aims to provide a comprehensive overview of the in vitro, animal, and clinical studies with the bacterial strain Lactiplantibacillus plantarum 299v (L. plantarum 299v; formerly named Lactobacillus plantarum 299v) published up until June 30, 2020. L. plantarum 299v is the most documented L. plantarum strain in the world, described in over 170 scientific publications out of which more than 60 are human clinical studies. The genome sequence of L. plantarum 299v has been determined and is available in the public domain (GenBank Accession number: NZ_LEAV01000004). The probiotic strain L. plantarum 299v was isolated from healthy human intestinal mucosa three decades ago by scientists at Lund University, Sweden. Thirty years later, a wealth of data coming from in vitro, animal, and clinical studies exist, showing benefits primarily for gastrointestinal health, such as reduced flatulence and abdominal pain in patients with irritable bowel syndrome (IBS). Moreover, several clinical studies have shown positive effects of L. plantarum 299v on iron absorption and more recently also on iron status. L. plantarum 299v is safe for human consumption and does not confer antibiotic resistance. It survives the harsh conditions of the human gastrointestinal tract, adheres to mannose residues on the intestinal epithelial cells and has in some cases been re-isolated more than ten days after administration ceased. Besides studying health benefits, research groups around the globe have investigated L. plantarum 299v in a range of applications and processes. L. plantarum 299v is used in many different food applications as well as in various dietary supplements. In a freeze-dried format, L. plantarum 299v is robust and stable at room temperature, enabling long shelf-lives of consumer healthcare products such as capsules, tablets, or powder sachets. The strain is patent protected for a wide range of indications and applications worldwide as well as trademarked as LP299V^®.

Antimicrobial susceptibilities and comparative whole genome analysis of two isolates of the probiotic bacterium Lactiplantibacillus plantarum, strain ATCC 202195

A synbiotic containing Lactiplantibacillus plantarum [American Type Culture Collection (ATCC) strain identifier 202195] and fructooligosaccharide was reported to reduce the risk of sepsis in young infants in rural India. Here, the whole genome of two isolates of L. plantarum ATCC 202195, which were deposited to the ATCC approximately 20 years apart, were sequenced and analyzed to verify their taxonomic and strain-level identities, identify potential antimicrobial resistant genes and virulence factors, and identify genetic characteristics that may explain the observed clinical effects of L. plantarum ATCC 202195. Minimum inhibitory concentrations for selected antimicrobial agents were determined using broth dilution and gradient strip diffusion techniques. The two L. plantarum ATCC 202195 isolates were genetically identical with only three high-quality single nucleotides polymorphisms identified, and with an average nucleotide identity of 99.99%. In contrast to previously published reports, this study determined that each isolate contained two putative plasmids. No concerning acquired or transferable antimicrobial resistance genes or virulence factors were identified. Both isolates were sensitive to several clinically important antibiotics including penicillin, ampicillin and gentamicin, but resistant to vancomycin. Genes involved in stress response, cellular adhesion, carbohydrate metabolism and vitamin biosynthesis are consistent with features of probiotic organisms.

Probiotics, Prebiotics, and Synbiotics in the Irritable Bowel Syndrome Treatment: A Review

Irritable bowel syndrome is not a life-threatening disease, yet it significantly affects the quality of life and contributes to economic loss. It is estimated that even up to 45% of the world's population can suffer from the disease. The first attempts to diagnose irritable bowel syndrome were made at the end of the 19th century; however, establishing appropriate diagnostic criteria and treatment methods is still ongoing. To date, little is known about the etiology of irritable bowel syndrome; however, growing attention is drawn to the intestinal microbiota as a factor in the disease development. For this reason, researchers have conducted many studies on therapies that modulate the microbiota, among which probiotics, prebiotics, and synbiotics are widely studied. To date, most studies have examined probiotics; however, there are also several studies demonstrating the efficacy of prebiotics and synbiotics. The aim of this review was to summarize findings on the usefulness of probiotics, prebiotics, and synbiotics in the treatment of irritable bowel syndrome.

Does probiotic supplementation aid weight loss? A randomized, single-blind, placebo-controlled study with Bifidobacterium lactis BS01 and Lactobacillus acidophilus LA02 supplementation

PURPOSE

Probiotic supplements are gaining popularity worldwide. This trend is especially present in females, and a common motivation for consumption is weight loss, no matter the BMI. The aim of this study was to investigate the effects of probiotic supplementation on weight loss in healthy, young adult females and to put claims made by manufacturers of such products to the test.

METHODS

The study utilizes a randomized, single-blind, placebo-control design. 53 females aged 19-33 were enrolled, and 38 completed the trial. A 6 week supplementation with Bifidobacterium lactis BS01 and Lactobacillus acidophilus LA02 or placebo was conducted. Anthropometric measures (body mass, BMI, body fat percentage, arm skinfold fat, waist circumference, and WHR) were applied pre and post-treatment.

RESULTS

No significant changes in anthropometric measures were observed in both supplementation and placebo groups.

CONCLUSION

The results of this investigation do not support claims made by probiotic products manufacturers, that they aid weight loss. Our results seem to support an argument that weight loss is mostly associated with food habits and dietary behaviors, not probiotic intake. It is possible that probiotic supplementation may play a facilitating weight loss but has no effect without dietary intervention. Another possible explanation is that due to strain specificity-bacteria strains used in this study are not effective for weight loss.

LEVEL OF EVIDENCE

I: randomized controlled trial.

Specific Probiotics for the Treatment of Pediatric Acute Gastroenteritis in India: A Systematic Review and Meta-Analysis

Pediatric acute gastroenteritis (PAGE) is a significant cause of morbidity, mortality and healthcare costs in many countries, but differences in PAGE vary from country-to-country; thus, we limited our analysis to 1 country. Probiotics have been recommended as an adjunct to standard treatment, but the choice of probiotic is unclear. PubMed, Google Scholar, and reviews were searched from inception to May 2020 for randomized controlled trials (RCTs) in India using probiotics for a treatment for PAGE. Meta-analyses using subgroups of identical probiotic types (≥2 RCT/type) were conducted for primary outcomes (duration of diarrhea, cured by day 3, rapidity of response, and length of hospital stay). Twenty-two RCTs were included in the systematic review (N = 4059 participants) including 5 single-strained probiotics and 3 multi-strained mixtures. For the meta-analyses, 17 RCT (20 treatment arms) were included. Saccharomyces boulardii CNCM I-745 had the strongest effect on shortening the duration of diarrhea (standardized mean difference, -1.86 d; 95% confidence interval, -2.8 to -0.9), while both Lactobacillus rhamnosus GG and a mixture of 4 Bacillus clausii strains (O/C, SIN, N/R, T) significantly reduced the duration of diarrhea (-1.7 and -1.4 d, respectively). S. boulardii and L. rhamnosus GG significantly reduced hospital stays (-1.8 and -1.1 d, respectively), while B. clausii had no effect. The frequency of stools/day was significantly reduced by day 4 for S. boulardii and by day 5 for L. rhamnosus GG. In India, 2 types of probiotics (S. boulardii CNCM I-745 and L. rhamnosus GG) significantly shortened both the duration of diarrhea and hospitalization stays in pediatric patients with PAGE. While these 2 probiotic strains were safe and effective for children in India, further research is needed to confirm if other probiotic strains or mixtures may be effective.

Lactobacillus plantarum PS128 Promotes Intestinal Motility, Mucin Production, and Serotonin Signaling in Mice

Lactobacillus plantarum PS128 has been reported as a psychobiotic to improve mental health through the gut–brain axis in experimental animal models. To explore its mechanism of action in the gut, this study aimed to analyze the effects of L. plantarum PS128 ingestion on naïve and loperamide (Lop)-induced constipation mice. We found that, in the two mouse models, the weight, number, and water content of feces in the L. plantarum PS128 group were higher than those in the vehicle control group. Histological observation revealed that L. plantarum PS128 increased the level of colonic mucins including the major mucin MUC2. In addition, the charcoal meal test showed that L. plantarum PS128 significantly increased the small intestine transit in naïve mice, but not in the Lop-treated mice. Since intestinal serotonin has been found to modulate motility, we further analyzed the expression of genes related to serotonin signal transduction in the small intestine of naïve mice. The results showed that L. plantarum PS128 significantly altered the expression levels of Tph1, Chga, Slc6a4, and Htr4, but did not affect the expression levels of Tph2, Htr3a, and Maoa. Furthermore, immunohistochemistry revealed that L. plantarum PS128 significantly increased the number of serotonin-containing intestinal cells in mice. Taken together, our results suggest that L. plantarum PS128 could promote intestinal motility, mucin production, and serotonin signal transduction, leading to a laxative effect in mice.