Probiotic Agents Research Articles

In vitro and in vivo evaluation of probiotic potential and safety assessment of Bacillus coagulans SKB LAB-19 (MCC 0554) in humans and animal healthcare

Bacillus coagulans is Gram positive, spore forming and high lactic acid producing bacteria; however, probiotic and safety assessment of the isolated strain need to be investigated for commercial applications. Current study aimed to screen SKB LAB-19 for potential probiotic characteristics viz. enzyme production, antimicrobial properties, pH/bile salt tolerance, temperature stability, antidiarrheal activity in Swiss albino mice and Wistar rats; and acute oral toxicity in mice. The results showed that, SKB LAB-19 produces eight potential enzymes, effective against E. coli and C. perfringensis, tolerant to bile salt (0.3%w/v)/gastric pH (2.5), stable at 40–90 °C and nontoxic to cells. SKB LAB-19 was found to be safe and displayed promising results to reverse E. coli and castor oil induced diarrhoea. Histopathological studies showed repair to damaged mucosal epithelium cells and improves integrity of the goblet cells of colon. SKB LAB-19 showed immunomodulatory effects with increased immunoglobulins in blood and augmented weight of spleen and thymus. In addition, SKB LAB-19 showed significant in-vitro antioxidant activity (82.93%), reducing capacity and ascorbate auto-oxidation inhibition effect (94.62%). These preliminary results suggested that, SKB LAB-19 was found to be safe and has the potential to be used as effective probiotic and anti-diarrhoeal agent in humans and animal healthcare.

The Effect of Fermentation Time on Product Quality of Cowpea (Vigna unguiculata L.Walp) Soft Cheese with Starter Culture of Lactobacillus plantarum B1765

This research was conducted to determine the effect of fermentation time on lactic acid bacteria (LAB), pH, total titrated acid (TTA) and organoleptic (taste, flavor, color and texture) of cowpea soft cheese (Vigna unguiculata L.Walp) with starter culture Lactobacillus plantarum B1765. L.plantarum B1765 had been studied has a probiotic characteristics. The fermentation time was 0, 6, 18 and 24 hours. The methods were total plate count (TPC) to measure the number of LAB, pH meter to measure pH, acid-base titration to measure TTA, and hedonic test for organoleptic. The results showed that the fermentation time affected the number of LAB, pH, TTA and organoleptic. The number of LAB increased by 3 log cycles from 8.7 x 106 CFU/mL to 5,3 x 109 CFU/mL. The pH value decreased from 6.53 to 3.69. The TTA value increased from 0.45% to 1.79%. The highest level of preference for taste, texture, color and flavor was at 18 hours of fermentation with a value of 3.17; 2.77; 2.70; 2.97 (likes). Cowpea soft cheese with starter L.plantarum B1765 could be improve potentially as vegetable cheese and probiotic agent.

Anti-Inflammatory Effects of Limosilactobacillus fermentum KGC1601 Isolated from Panax ginseng and Its Probiotic Characteristics.

We investigated the potential probiotic properties of Limosilactobacillus fermentum KGC1601 isolated from Panax ginseng. Ginseng cultivated in an experimental field of the Korea Ginseng Research Institute was fermented, followed by single colony selection from MRS agar. We performed 16s-rRNA sequencing and whole-genome analysis to identify L. fermentum and evaluate the biosafety parameters of this strain, respectively. We confirmed this strain was susceptible to six antibiotics, as proposed by the European Food Safety Authority, did not produce biogenic amines, and did not exhibit any hemolytic activity. Acid resistance and bile salt tolerance, which are essential properties of a probiotic agent, were investigated. Notably, distinguishing properties of this strain were that it exhibited excellent bile salt tolerance and anti-inflammatory effects. The excellent bile salt tolerance was confirmed by scanning electron microscopy. Through qRT-PCR and ELISA studies, it was revealed that L. fermentum KGC1601 pre-treatment up-regulates anti-inflammatory cytokines and down-regulates pro-inflammatory cytokines in RAW 264.7 cells. Consequently, we suggested that L. fermentum KGC1601 can be safely used as a potential anti-inflammatory functional probiotic agent.

Comparative genomics analysis of Bacillus velezensis LOH112 isolated from a nonagenarian provides insights into its biocontrol and probiotic traits

Bacillus velezensis has recently received increasing attention as a biological fungicide and a potential probiotic agent because of its broad spectrum of antibacterial and antifungal activities. Here, we evaluated the beneficial traits of a newly isolated B. velezensis strain LOH112 using comprehensive bioinformatics and comparative genomic analyses and in vitro experimental approaches. Whole genome sequencing and assembly results showed that the genome of LOH112 consists of a circular chromosome and a circular plasmid, which encodes proteins involved in important biological processes such as sporulation, quorum sensing, and antibiotic synthesis. LOH112 contains 13 secondary metabolism gene clusters responsible for the production of antimicrobial compounds. In vitro experiments showed that LOH112 effectively inhibits several fungi and Gram-positive pathogenic bacteria, hydrolyzes protein and cellulose, and is capable of forming strong adhesive biofilms. Furthermore, comparative genomics revealed that LOH112 contains 34 strain-specific orthologous gene clusters, including two caseinolytic protease P (clpP) genes responsible for proteomic homeostasis. Selective pressure analysis indicated that the transmembrane transporter and ATP-dependent alanine/valine adenylase genes were strongly positively selected, which may endow LOH112 with better biocontrol ability and potential probiotic properties. Collectively, these results not only provide insights into a deeper understanding of the genomic characterization of LOH112 but also imply the potential application of LOH112 as biocontrol and probiotic agents.

Antiviral Effects and Underlying Mechanisms of Probiotics as Promising Antivirals.

Probiotics exert a variety of beneficial effects, including maintaining homeostasis and the balance of intestinal microorganisms, activating the immune system, and regulating immune responses. Due to the beneficial effects of probiotics, a wide range of probiotics have been developed as probiotic agents for animal and human health. Viral diseases cause serious economic losses to the livestock every year and remain a great challenge for animals. Moreover, strategies for the prevention and control of viral diseases are limited. Viruses enter the host through the skin and mucosal surface, in which are colonized by hundreds of millions of microorganisms. The antiviral effects of probiotics have been proved, including modulation of chemical, microbial, physical, and immune barriers through various probiotics, probiotic metabolites, and host signaling pathways. It is of great significance yet far from enough to elucidate the antiviral mechanisms of probiotics. The major interest of this review is to discuss the antiviral effects and underlying mechanisms of probiotics and to provide targets for the development of novel antivirals.

Effect of Saccharomyces cerevisiae on Probiotic Properties of Goat Milk Kefir

Goat milk kefir is a fermented milk product with kefir grain, as a probiotic agent and contains bioactive compounds. Kefir grains consist of bacteria and yeast. One of these yeasts are Saccharomyces cerevisiae, its role in the kefir system can be enhanced by restructure of kefir grain with increased Saccharomyces cerevisiae population. The objectives of this research were to analysis effect of the Saccharomyces cerevisiae concentration levels on kefir, as antibacterial against Escherichia coli, Salmonella typhi. Klebsiella pneumoniae, antioxidant activity, β-galactosidase synthesis. The research method was true experiment by Completely Randomized Design consist of 5 kind Saccharomyces cerevisiae concentration levels (S0: control; S1: 0.10%; S2: 0,25%; S3: 0.5% and S4: 1.0% v/w) of kefir grain. The results showed that kefir inhibited Escherichia coli, Salmonella typhi and Klebsiella pneumoniae, able to produce β-galactosidase and antioxidant activity. Kefir is relevant as food functional development.

Plasmid-Based Gene Expression Systems for Lactic Acid Bacteria: A Review.

Lactic acid bacteria (LAB) play a very vital role in food production, preservation, and as probiotic agents. Some of these species can colonize and survive longer in the gastrointestinal tract (GIT), where their presence is crucially helpful to promote human health. LAB has also been used as a safe and efficient incubator to produce proteins of interest. With the advent of genetic engineering, recombinant LAB have been effectively employed as vectors for delivering therapeutic molecules to mucosal tissues of the oral, nasal, and vaginal tracks and for shuttling therapeutics for diabetes, cancer, viral infections, and several gastrointestinal infections. The most important tool needed to develop genetically engineered LABs to produce proteins of interest is a plasmid-based gene expression system. To date, a handful of constitutive and inducible vectors for LAB have been developed, but their limited availability, host specificity, instability, and low carrying capacity have narrowed their spectrum of applications. The current review discusses the plasmid-based vectors that have been developed so far for LAB; their functionality, potency, and constraints; and further highlights the need for a new, more stable, and effective gene expression platform for LAB.

Saccharomyces boulardii plus azithromycin is superior to azithromycin alone in reducing the duration of diarrhea in children with acute colitis: a double-blind randomized placebo-controlled trial

Introduction: Diarrheal disorders remain a major disease burden throughout the world in pediatrics that remains a health problem. Several treatment methods have been proposed to treat diarrhea, however each of them has some problems. Objectives: The aim of this study was the evaluation the effect of oral Saccharomyces boulardii on the duration and severity of colitis. Patients and Methods: This randomized clinical trial study included ninety-four patients with acute colitis were enrolled. The children were divided randomly into case and control groups. The control group received supportive treatment including intravenous or oral fluid therapy (ORS solution), antibiotic treatment with azithromycin suspension, and zinc sulfate syrup daily for five days. In addition to the mentioned treatments, the intervention group received S. boulardii as a probiotic capsule. Then, the duration and severity of diarrhea based on the Vesikari score were evaluated for all the patients for five first days. Results: The mean of Vesikari score after the first day in both groups was similar, while after the third and fifth day in the probiotic group this score was lower than the control group (5.11 ± 1.73 versus 6.13 ± 2.25, P=0.031 and 2.36 ± 1.16 versus 4.28 ±1.19, P<0.001, respectively). Furthermore, the number of diarrhea per day in the probiotic group was significantly lower after the first day in contrast to the control group, which remains significant at the end of the fifth day (2.32 ± 0.51 versus 2.83 ± 1.23, P=0.047). Moreover, we found that the diarrhea duration (P<0.001), fever duration (P=0.029), and duration of hospitalization (P=0.006) were statistically lower in the case group as compared to the control. Conclusion: Saccharomyces boulardii had a beneficial effect as a probiotic agent in reducing the severity and duration of diarrhea, which could be beneficial for the treatment of colitis. Trial Registration: The trial protocol was approved by the Iranian Registry of Clinical Trials (identifier: IRCT20161026030525N2); https://www.irct.ir/trial/24229; ethical code: IR.AJUMS.REC.1395.54.

Disease-associated dysbiosis and potential therapeutic role of Akkermansia muciniphila, a mucus degrading bacteria of gut microbiome.

The unique functionality of Akkermansia muciniphila in gut microbiota indicates it to be an indispensable microbe for human welfare. The importance of A. muciniphila lies in its potential to convert mucin into beneficial by-products, regulate intestinal homeostasis and maintain gut barrier integrity. It is also known to competitively inhibit other mucin-degrading bacteria and improve metabolic functions and immunity responses in the host. It finds a pivotal perspective in various diseases and their treatment. It has future as a promising probiotic, disease biomarker and therapeutic agent for chronic diseases. Disease-associated dysbiosis of A. muciniphila in the gut microbiome makes it a potential candidate as a biomarker for some diseases and can provide future theranostics by suggesting ways of diagnosis for the patients and best treatment method based on the screening results. Manipulation of A. muciniphila in gut microbiome may help in developing a novel personalized therapeutic action and can be a suitable next generation medicine. However, the actual pathway governing A. muciniphila interaction with hosts remains to be investigated. Also, due to the limited availability of products containing A. muciniphila, it is not exploited to its full potential. The present review aims at highlighting the potential of A. muciniphila in mucin degradation, contribution towards the gut health and host immunity and management of metabolic diseases such as obesity and type 2 diabetes, and respiratory diseases such as cystic fibrosis and COVID-19.

Prevalence and genetic diversity of Giardia duodenalis in pet dogs from Zhengzhou, central China and the association between gut microbiota and fecal characteristics during infection

As a common zoonotic intestinal parasite, Giardia duodenalis could infect humans and various mammals worldwide, including pet dogs, leading to giardiasis. This study detected the infection of G. duodenalis in asymptomatic pet dogs in Zhengzhou, and evaluated the possibility of zoonosis and the relationship between gut microbiota and fecal characteristics. We randomly collected 448 fresh fecal samples from Zhengzhou, and G. duodenalis was screened based on the beta-giardin (bg), glutamate dehydrogenase (gdh), and triose phosphate isomerase (tpi) genes. The difference of gut microbiota between five G. duodenalis-positive and five G. duodenalis-negative samples was investigated by 16S rRNA gene sequencing. The overall prevalence of G. duodenalis was 7.1% (32/448) based on bg, gdh, and tpi locus, two G. duodenalis assemblages (C = 13, D = 14) and five (15.6%) mixed infection (C + D) were identified. Moreover, compared with the G. duodenalis-negative group, the diversity of gut microbiota increased in G. duodenalis-positive group. The decrease of Lactobacillus spp. and considerable increase of Prevotella spp. were associated with the fecal characteristics. These results show that the transmission of zoonotic giardiasis between humans and pet dogs is rare in Zhengzhou, central China, and support the use of Lactobacillus spp. as a potential probiotic agent to improve intestinal health in dogs, or even humans, by treating G. duodenalis. Therefore, the public health significance of G. duodenalis to humans, companion animals, and the environment should be further evaluated from One Health perspective.

Antagonistic activity and mechanism of Lactobacillus rhamnosus SQ511 against Salmonella enteritidis.

Salmonella enteritidis is an important food-borne pathogen. The use of antibiotics is a serious threat to animal and human health, owing to the existence of resistant strains and drug residues. Lactic acid bacteria, as a new alternative to antibiotics, has attracted much attention. In this study, we investigated the antibacterial potential and underlying mechanism of Lactobacillus rhamnosus SQ511 against S. enteritidis ATCC13076. The results revealed that L. rhamnosus SQ511 significantly inhibited S. enteritidis ATCC13076 growth or even caused death. Laser confocal microscopic imaging revealed that the cell-free supernatant (CFS) of L. rhamnosus SQ511 elevated the reactive oxygen species level and bacterial membrane depolarization in S. enteritidis ATCC13076, leading to cell death. Furthermore, L. rhamnosus SQ511 CFS had severely deleterious effects on S. enteritidis ATCC13076, causing membrane destruction and the release of cellular materials. In addition, L. rhamnosus SQ511 CFS significantly reduced the expression of virulence, motility, adhesion, and invasion genes in S. enteritidis ATCC13076 (P < 0.05), and considerably inhibited motility and biofilm formation capacity (P < 0.05). Thus, antimicrobial compounds produced by L. rhamnosus SQ511 strongly inhibited S. enteritidis growth, mobility, biofilm formation, membrane disruption, and reactive oxygen species generation, and regulated virulence-related gene expressions, presenting promising applications as a probiotic agent.

Dietary supplementation of Bacillus velezensis improves Vibrio anguillarum clearance in European sea bass by activating essential innate immune mechanisms

Bacillus spp. supplementation as probiotics in cultured fish diets has a long history of safe and effective use. Specifically, B. velezensis show great promise in fine-tuning the European sea bass disease resistance against the pathogenicity caused by several members of the Vibrio family. However, the immunomodulatory mechanisms behind this response remain poorly understood. Here, to examine the inherent immune variations in sea bass, two equal groups were fed for 30 days with a steady diet, with one treatment supplemented with B. velezensis. The serum bactericidal capacity against live cells of Vibrio anguillarum strain 507 and the nitric oxide and lysozyme lytic activities were assayed. At the cellular level, the phagocytic response of peripheral blood leukocytes against inactivated Candida albicans was determined. Moreover, head-kidney (HK) total leukocytes were isolated from previously in vivo treated fish with LPS of V. anguillarum strain 507. Mechanistically, the expression of some essential proinflammatory genes (interleukin-1 (il1b), tumor necrosis factor-alpha (tnfa), and cyclooxygenase 2 (cox2) and the sea bass specific antimicrobial peptide (AMP) dicentracin (dic) expressions were assessed. Surprisingly, the probiotic supplementation significantly increased all humoral lytic and cellular activities assayed in the treated sea bass. In addition, time-dependent differences were observed between the control and probiotic treated groups for all the HK genes markers subjected to the sublethal LPS dose. Although the il1b was the fastest responding gene to a significant level at 48 h post-injection (hpi), all the other genes followed 72 h in the probiotic supplemented group. Finally, an in vivo bacteria challenge against live V. anguillarum was conducted. The probiotic fed fish observed a significantly higher survival. Overall, our results provide clear vertical evidence on the beneficial immune effects of B. velezensis and unveil some fundamental immune mechanisms behind its application as a probiotic agent in intensively cultured European sea bass.

Effects of probiotic interventions on production efficiency, survival rate, and immune responses of Macrobrachium rosenbergii (de Man) prawns: A meta-analysis and meta-regression

Probiotics are widely used in commercial shrimp aquaculture, but responses are variable. The objectives of this study were to quantitatively review using meta-analysis the production, survival, and immune responses of Macrobrachium rosenbergii to probiotics and to identify sources of residual variation. A total of 58 comparisons from 16 experiments (full text articles) were included in the final meta-analyses. Classical meta-analysis was used to analyse differences in responses by weighted mean difference (WMD) and standardised mean difference (SMD). Estimates were pooled using DerSimonian and Laird random effects models (D&L); nesting of treatment comparisons within experiment were accounted for by robust regression models (RR). The RR were also used to assess the influence of covariables: initial body weight (BW), method of delivery (feed or water), number of days of probiotic delivery, developmental stage (juvenile or post-larval), probiotic concentration, probiotic genus (Bacillus or Lactobacillus), and diet on the outcomes. Probiotics increased final BW by 1.87 SMD (95% CI = 0.28 to 3.46) and weight gain percent by 1.57 SMD (95% CI = 0.14 to 3.00), compared to the reference prawns. Feed to gain was improved with probiotics by 0.53 g/g (16.7%) or − 1.61 SMD (95% CI = −2.63 to −0.60) with greater efficiency for Bacillus probiotics compared to Lactobacillus (SMD = −3.40; 95% CI = −4.66 to −2.14). Specific growth rate was increased by 0.21% per d (95% CI = 0.09 to 0.32), an improvement of 11.2% or 1.32 SMD (95% CI = 0.38 to 2.25) and survival rate by 1.03 SMD (95% CI = 0.21 to 1.85). Probiotics influenced immune and haemolymph measures by D&L evaluation but not RR, suggesting more experiments are required in this field. The outcomes were considerably heterogeneous, indicating a large amount of residual variation was attributable to study conduct. The variance for RR models was low signifying that accounting for the effects of comparison within experiment explained much of the variance. Covariables rarely explained the variation and were not consistent across outcomes. In summary, interventions with probiotics in M. rosenbergii improved growth performance and survival, may be influenced by probiotic agent, and are likely to lead to economic benefits for industry.

Effect of Bacell-M probiotic supplementation on the residual amount of antibiotics in milk

This article describes the use of the prophylactic effectiveness of probiotic preparation Bacell-M in obstetric-gynecological diseases and mastitis in cows. Duration of recording of residual amount of antibiotic in milk with combined application of Bacell-M with antibiotics is established. The effect of probiotic supplement on milk quality indicators was studied. This probiotic Bacell-M supplement at a dose of 60 g. per head prevents the incidence of cows of obstetric and gynecological pathology. The number of follow-up detention is reduced by 6.7%, subinvolution of the uterus by 13.3% compared to the control group. Postpartum animals (post-calving follow-up) were not recorded in both trial groups, and 6.6% and 13.3% of cows were diagnosed in control groups, respectively. The incidence of acute endometritis in both the experimental and control groups was diagnosed in one percent, but in the experimental groups it was 6.6% lower. The incidence of mastitis in the control groups ranged from 26.6 to 33.3%. However, the use of the probiotic supplement Bacell-M reduced the incidence by 13.3 and 26.7%, respectively. The use of an antibacterial preparation against the background of the use of probiotic agents reduces the time of antibiotic registration in milk by 19,6 hours. Based on the obtained data, the positive effect is confirmed by the use of a fodder probiotic supplement as an agent for the prevention of gynecological diseases and mastitis in cows. Reduced time of antibiotic presence in cow milk and beneficial effect on milk quality are proved.

Functional meat products: Trends in pro-, pre-, syn-, para- and post-biotic use

In recent years, many studies have been conducted to develop functional meat products, focusing on strategies to maximize health-promoting compounds and reduce the presence of those that may cause negative impacts on the consumer's health. As such, the use of prebiotic, probiotic, and synbiotic agents in meat products has grown considerably. In addition, the use of new generation probiotics in meat products is a novel field that can be explored. With the most recent paraprobiotics/postbiotics update, several components could be tested in meat products. Some interventional studies using meat products added with biotic agents have shown great potential as functional foods by reducing the formation of nitrous compounds in the gut and improving the functionality of the gut microbiota. Although there are few studies focusing on synbiotic meat products, the results are also very promising in this field. As such, this review seeks to describe how probiotics, prebiotics, paraprobiotics and postbiotics can be employed in meat products to give them functional properties, as well as some of the major issues that may arise when using these agents.

Effect of Prebiotics and Synbiotics Carried by Food over Irritable Bowel Syndrome Symptoms: A Systematic Review

Irritable bowel syndrome (IBS) is a chronic condition that affects 11.2% of the world’s population. The management of gut microbiota using probiotic and synbiotic agents might be a valid alternative to assist in the treatment of IBS. The focus of this study was to evaluate the effects of prebiotic and synbiotic compounds carried by different foods on major symptoms of IBS through a systematic literature review. MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and LILACS were accessed during July 2021. The studies included in this review were the ones that tested volunteers older than 16 years of age and were conducted using a randomized, controlled clinical trial. The risk of bias was assessed by using the Cochrane risk-of-bias tool for randomized trials (RoB2). Furthermore, the data found were qualitatively evaluated due to the studies’ differences. Two papers were able to fit the criteria, with a total sample size of 280 participants. No datum was found regarding the use of prebiotics in the treatment of IBS. Synbiotic agents, however, had a positive effect on gastrointestinal symptoms and the participants’ overall bowel satisfaction; however, it was not possible to reach a consensus on which effects. Further studies regarding the use of synbiotics and prebiotics must be carried out to determine which effects are the most significant in the treatment of IBS.

The growth performance of Peking ducks fed with rations containing probiotic agents and waste products of leubiem fish (Chanthidermis maculatus)

The purpose of this study was to evaluate the growth performance of Peking ducks fed with rations containing waste products of leubiem fish (Chanthidermis maculatus) and probiotic agents. The study was conducted experimentally using 96 Peking ducks, within an age range of about 1 to 8 weeks, and a Completely Randomized Design (CRD), which consisted of four treatment rations and four replications. The treatment rations used in this research included treatment R0, which was the basal diet, serving as the control ration, and also treatment R1, R2, and R3, which consisted of 10% concentration of leubiem fish skin, head, and bone, respectively, as well as 1% of a probiotic agent. The observed variables included the rate of feed consumption, body weight gain, final body weight, feed conversion ratio, and mortality were then analysed using Analysis of Variance (ANOVA). The results showed that the use of leubiem fish components and probiotic agents in rations at 10% and 1%, respectively, had a significant effect (p<0.05) on the rate of feed consumption, body weight gain, feed conversion ratio and final body weight. However, there was no significant effect on the mortality of Peking ducks. Therefore, this study concluded that the use of rations containing leubiem fishbone and probiotic agents at 10% and 1%, respectively, were able to accelerate the growth performance of Peking ducks.

Lactobacillus salivarius HHuMin-U Activates Innate Immune Defense against Norovirus Infection through TBK1-IRF3 and NF-κB Signaling Pathways.

The composition of commensal bacteria plays a critical role in controlling immune responses in the intestine. Studies have shown that specific bacterial strains may have the capacity to enhance host immune defense against gastrointestinal viral infections. While norovirus is known to be the most common cause of gastroenteritis, leading to an estimated 200,000 deaths every year, identification of bacterial strains with protective effects against norovirus infection remains elusive. Here, we discovered Lactobacillus salivarius HHuMin-U (HHuMin-U) as a potent antiviral strain against norovirus infection. HHuMin-U significantly suppressed murine norovirus replication and lowered viral RNA titers in macrophages. The transcriptome sequencing (RNA sequencing) analysis revealed that HHuMin-U markedly enhanced the expression level of antiviral interferon-stimulated genes compared to mock treatment. HHuMin-U treatment dose-dependently induced type I interferons (IFN-α and IFN-β) and tumor necrosis factor-α production in mouse and human macrophages, promoting antiviral innate responses against norovirus infection. Investigation on the molecular mechanism demonstrated that HHuMin-U can activate nuclear factor κB and TANK-binding kinase 1 (TBK1)-interferon regulatory factor 3 signaling pathways, leading to the phosphorylation of signal transducer and activator of transcription 1 and signal transducer and activator of transcription 2, the key mediators of interferon-stimulated genes. Finally, oral administration of HHuMin-U increased IFN-β levels in the ileum of mice and altered the gut microbiome profile. These results suggest the species/strain-specific importance of gut microbial composition for antiviral immune responses and the potential use of HHuMin-U as a probiotic agent.

Antidiabetic potential of polysaccharides from Brasenia schreberi regulating insulin signaling pathway and gut microbiota in type 2 diabetic mice

This study aimed to investigate the hypoglycemic activities and gut microbial regulation effects of polysaccharides from Brasenia schreberi (BS) in diabetic mice induced by high-fat diet and streptozotocin. Our data indicated that BS polysaccharides not only improved the symptoms of hyperglycemia and relieved metabolic endotoxemia-related inflammation but also optimized the gut microbiota composition of diabetic mice with significantly decreased Firmicutes/Bacteroidetes ratios. More importantly, altered gut microbiota components may affect liver glycogen and muscle glycogen by increasing the mRNA expression of phosphatidylinositol-3-kinase (PI3K) and protein kinase B (Akt) in the liver of mice through modulated the abundance of beneficial bacteria (Lactobacillus). Altogether, our findings, for the first time, demonstrate that BS polysaccharides may be used as a beneficial probiotic agent that reverses gut microbiota dysbiosis and the hypoglycemic mechanisms of BS polysaccharides may be related to enhancing the abundance of Lactobacillus to activate PI3K/Akt-mediated signaling pathways in T2DM mice.

The Integrated Probiotic Database: a genomic compendium of bifidobacterial health-promoting strains.

Background: The World Health Organization defines probiotics as "live microorganisms, which when administered in adequate amounts confer a health benefit on the host". In this framework, probiotic strains should be regarded as safe for human and animal consumption, i.e., they should possess the GRAS (generally recognized as safe) status, notified by the local authorities. Consistently, strains of selected Bifidobacterium species are extensively used as probiotic agents to prevent and ameliorate a broad spectrum of human and/or animal gastrointestinal disorders. Even though probiotic properties are often genus- or species-associated, strain-level differences in the genetic features conferring individual probiotic properties to commercialized bifidobacterial strains have not been investigated in detail. Methods: In this study, we built a genomic database named Integrated Probiotic DataBase (IPDB), whose first iteration consists of common bifidobacterial strains used in probiotic products for which public genome sequences were available, such as members of B. longum subsp. longum, B. longum subsp. infantis, B. bifidum, B. breve, and B. animalis subsp. lactis taxa. Furthermore, the IPDB was exploited to perform comparative genome analyses focused on genetic factors conferring structural, functional, and chemical features predicted to be involved in microbe-host and microbe-microbe interactions. Results and conclusion: Our analyses revealed strain-level genetic differences, underlining the importance of inspecting the strain-specific and outcome-specific efficacy of probiotics. In this context, IPDB represents a valuable resource for obtaining genetic information of well-established bifidobacterial probiotic strains.