Review on Bifidobacterium bifidum BGN4: Functionality and Nutraceutical Applications as a Probiotic Microorganism

Bifidobacterium exopolysaccharides: new insights into engineering strategies, physicochemical functions, and immunomodulatory effects on host health

Bifidobacteria are a prominent type of bacteria that have garnered significant research attention for their exceptional probiotic properties and capacity to produce exopolysaccharides (EPSs). These compounds exhibit diverse physical, chemical, and biological characteristics, prompting numerous investigations into their potential applications. Researchers have noted their beneficial effects as immune modulators within the host's body across various industries. Extensive research has been conducted on the immunomodulatory effects of bifidobacteria-derived EPSs, with emerging engineering strategies aimed at enhancing their immune-modulating capabilities. Understanding the structure, physicochemical properties, and biological activities of these compounds is crucial for their effective utilization across different industries. Our review encompassed numerous studies exploring Bifidobacterium and its metabolites, including EPSs, across various sectors, drawing from diverse databases. The distinctive properties of EPSs have spurred investigations into their applications, revealing their potential to bolster the immune system, combat inflammation, and treat various ailments. Additionally, these compounds possess antioxidant and antimicrobial properties, making them suitable for incorporation into a range of products spanning food, health, and medicine.

The Potential Impact of Probiotics on Human Health: An Update on Their Health-Promoting Properties

Probiotics, known to be live microorganisms, have been shown to improve or restore the gut microbiota, which in turn has been linked to improved health. It is believed that probiotics are the modern equivalent of a panacea, with claims that they may treat or prevent different diseases both in children and adults (e.g., from colic in babies to cardiovascular disease, respiratory infection, and cancer in adults). Ever since the early 2000s, probiotic-based fermented foods have had a resurgence in popularity, mostly due to claims made regarding their health benefits. Fermented foods have been associated with the prevention of irritable bowel syndrome, lactose intolerance, gastroenteritis, and obesity, but also other conditions such as chronic diarrhea, allergies, dermatitis, and bacterial and viral infections, all of which are closely related to an unhealthy lifestyle. Recent and ongoing developments in microbiome/microbiota science have given us new research directions for probiotics. The new types, mechanisms, and applications studied so far, and those currently under study, have a great potential to change scientific understanding of probiotics' nutritional applications and human health care. The expansion of fields related to the study of the microbiome and the involvement of probiotics in its improvement foreshadow an era of significant changes. An expanding range of candidate probiotic species is emerging that can address newly elucidated data-driven microbial niches and host targets. In the probiotic field, new variants of microbiome-modulating interventions are being developed, including prebiotics, symbiotics, postbiotics, microbial consortia, live biotherapeutic products, and genetically modified organisms, with renewed interest in polyphenols, fibers, and fermented foods to ensure human health. This manuscript aims to analyze recent, emerging, and anticipated trends in probiotics (sources, doses, mechanism of action, diseases for which probiotics are administered, side effects, and risks) and create a vision for the development of related areas of influence in the field.

A comprehensive review of Bifidobacterium spp: as a probiotic, application in the food and therapeutic, and forthcoming trends

Recently, more consumers are interested in purchasing probiotic food and beverage products that may improve their immune health. The market for functional foods and beverages that include Bifidobacterium is expanding because of their potential uses in both food and therapeutic applications. However, maintaining Bifidobacterium's viability during food processing and storage remains a challenge. Microencapsulation technique has been explored to improve the viability of Bifidobacterium. Despite the technical, microbiological, and economic challenges, the market potential for immune-supporting functional foods and beverages is significant. Additionally, there is a shift toward postbiotics as a solution for product innovation, a promising postbiotic product that can be incorporated into various food and beverage formats is also introduced in this review. As consumers become more health-conscious, future developments in the functional food and beverage market discussed in this review could serve as a reference for researchers and industrialist.

Effects of Bifido, Yijunkang, Siliankang, and Golden Bifid on loperamide induced constipation

BACKGROUND

Constipation is a common gastrointestinal disorder and a risk factor for colorectal cancer. Probiotics are the most widely used microecological agents for the treatment of constipation in clinical practice. Common intestinal microecological drugs include Bifido, Yijunkang, Siliankang, Golden Bifid, etc. They have different composition and may have different therapeutic effects on constipation.

AIM

To compare the effects of the four microecological agents in a rat model of constipation and to assess the effects of these probiotics on constipation-related indicators.

METHODS

Rats were randomly divided into six groups: Control group, model group, Bifido group, Yijunkang group, Siliankang group, and Golden Bifid group, with 10 rats in each group. The body weight, fecal quantity, shape, and water content, and intestinal transit rate of rats in each group were measured. Hematoxylin-eosin staining was performed to observe the pathological changes in the intestine of rats in each group. The expression level of intestinal mucin was analyzed by Alcian blue staining.

RESULTS

There were no significant changes in body weight and fecal water content of rats in each group. Compared to the model group, the quantity of feces (P < 0.01), intestinal transit rate (P < 0.05), intestinal mucosal thickness (P < 0.01), and mucin expression level (P < 0.01) were significantly increased in the Bifido group. Intestinal transit rate (P < 0.05) and mucin expression (P < 0.001) were significantly increased in the Yijunkang group. Increased intestinal transit rate and mucin level were observed in the Siliankang group (P < 0.05), and increased mucin expression was observed in the Golden Bifid group (P < 0.01).

CONCLUSION

The four microecological preparations improve constipation to varying degrees, of which Bifido has the best effect. Bifido can significantly increase the quantity of feces and intestinal transit rate of constipation rats, increase the expression level of mucin, promote the secretion of intestinal mucus, improve gastrointestinal peristalsis, and relieve constipation related symptoms.

Gut microbiota indole-3-propionic acid mediates neuroprotective effect of probiotic consumption in healthy elderly: A randomized, double-blind, placebo-controlled, multicenter trial and in vitro study

BACKGROUND & AIMS

The beneficial effects of probiotic consumption on age-related decline in cerebral function have been previously reported in the literature; however, the mechanistic link between gut and brain interactions has not yet been fully elucidated. Therefore, this study aimed to identify the role of gut microbiota-derived metabolites in gut-brain interactions via blood metabolomic profiling analysis in clinical trials and in vitro mechanistic studies.

METHODS

A randomized, double-blind, placebo-controlled, multicenter clinical trial was conducted in 63 healthy elderly individuals (≥65 years of age). Participants were administered either placebo (placebo group, N = 31) or probiotic capsules (Bifidobacterium bifidum BGN4 and Bifidobacterium longum BORI; probiotics group, N = 32) for 12 weeks. Global and targeted metabolomic profiling analyses of their blood samples were then performed using ¹H nuclear magnetic resonance and liquid chromatography-mass spectrometry methods, both at baseline and at the end of the trial. Gut microbial analysis was conducted using the 16S ribosomal ribonucleic acid gene sequencing method. Subsequently, microglial BV2 cells were treated in vitro with indole-3-propionic acid (IPA) following lipopolysaccharide stimulation, and neuronal SH-SY5Y cells were treated with conditioned media from the BV2 cells. Finally, the levels of pro-inflammatory cytokines in BV2 cells and neurotrophins in SH-SY5Y cells were quantified using a real-time polymerase chain reaction or enzyme-linked immunosorbent assay.

RESULTS

The metabolomic profiling analyses showed that probiotic consumption significantly altered the levels of metabolites involved in tryptophan metabolism (P < 0.01). Among these metabolites, gut microbiota-produced IPA had a 1.91-fold increase in the probiotics group (P < 0.05) and showed a significant relation to gut bacterial profiles (P < 0.01). Elevated IPA levels were also positively associated with the level of serum brain-derived neurotropic factor (BDNF) in the probiotics group (r = 0.28, P < 0.05), showing an inverse trend compared to the placebo group. In addition, in vitro treatment with IPA (5 μM) significantly reduced the concentration of proinflammatory TNF-α in activated microglia (P < 0.05), and neuronal cells cultured with conditioned media from IPA-treated microglia showed a significant increase in BDNF and nerve growth factor production (P < 0.05).

CONCLUSIONS

These results show that gut microbiota-produced IPA plays a role in protecting the microglia from inflammation, thus promoting neuronal function. Therefore, this suggests that IPA is a significant mediator linking the interaction between the gut and the brain in the elderly with probiotic supplementation.

The Influence of Gut Microbial Species on Diabetes Mellitus

Diabetes mellitus (DM) is a metabolic disorder with an alarming incidence rate and a considerable burden on the patient's life and health care providers. An increase in blood glucose level and insulin resistance characterizes it. Internal and external factors such as urbanization, obesity, and genetic mutations could increase the risk of DM. Microbes in the gut influence overall health through immunity and nutrition. Recently, more studies have been conducted to evaluate and estimate the role of the gut microbiome in diabetes development, progression, and management. This review summarizes the current knowledge addressing three main bacterial species: Bifidobacterium adolescentis, Bifidobacterium bifidum, and Lactobacillus rhamnosus and their influence on diabetes and its underlying molecular mechanisms. Most studies illustrate that using those bacterial species positively reduces blood glucose levels and activates inflammatory markers. Additionally, we reported the relationship between those bacterial species and metformin, one of the commonly used antidiabetic drugs. Overall, more research is needed to understand the influence of the gut microbiome on the development of diabetes. Furthermore, more efforts are required to standardize the model used, concentration ranges, and interpretation tools to advance the field further.

Phenotypic Traits and Probiotic Functions of Lactiplantibacillus plantarum Y42 in Planktonic and Biofilm Forms

Bacteria in planktonic and biofilm forms exhibit different phenotypic properties. In this study, the phenotypic traits and probiotic functions of Lactiplantibacillus plantarum Y42 in planktonic and biofilm forms were assessed. After 36 h of static culture, scanning electron microscopy and confocal laser scanning microscopy showed that the L. plantarum Y42 bacterial cells contained interconnected adhesive matter on the surface, forming a ~18 μm layer of dense biofilms. The surface properties of L. plantarum Y42 in biofilm form, including autoaggregation ability, hydrophobicity, acid-base charge, and adhesiveness, were all higher than those in the planktonic form. Biofilm L. plantarum Y42 showed a higher tolerance to adverse environmental conditions and a higher survival rate, enzymatic activity, and integrity after vacuum lyophilization. And biofilm L. plantarum Y42 had higher adhesion to human enterocyte HT-29 cell monolayers, inhibited the expressions of proinflammatory factors IL-6 and TNF-α, and promoted the expressions of the anti-inflammatory factor IL-10 and barrier proteins Claudin-1 and Occludin. In addition, L. plantarum Y42 in biofilm form can inhibit the adhesion and invasion of Listeria monocytogenes ATCC 19115 to HT-29 cell monolayers and is more effective in relieving the inflammatory reactions and injuries of HT-29 cells caused by L. monocytogenes ATCC 19115. In conclusion, L. plantarum Y42 in biofilm form exhibited better probiotic functions compared to that in planktonic form. This indicated that L. plantarum Y42 can form biofilms to enhance its probiotic functions, which provided a theoretical basis for better development and utilization of L. plantarum Y42.

Genomic and metabolic properties of Staphylococcus gallinarum FCW1 MCC4687 isolated from naturally fermented coconut water towards GRAS assessment

Staphylococcus gallinarum FCW1 was isolated from naturally fermented coconut-water and identified by biochemical and molecular methods. Probiotic characterization and safety assessment were conducted through a series of in vitro tests. A high survival rate was observed when the strain was tested for resistance to bile, lysozyme, simulated gastric and intestinal fluid, phenol, and different temperature and salt concentrations. The strain showed antagonism against some pathogens, was susceptible to all antibiotics tested except penicillin, and showed no hemolytic and DNase activity. Hydrophobicity, autoaggregation, biofilm formation, and antioxidation tests indicated that the strain possessed a high adhesive and antioxidant ability. Enzymatic activity was used to evaluate the metabolic capacities of the strain. In-vivo experiment on zebrafish was performed to check its safety status. The whole-genome sequencing indicated that the genome contained 2,880,305 bp with a GC content of 33.23%. The genome annotation confirmed the presence of probiotic-associated genes and genes for oxalate degradation, sulfate reduction, acetate metabolism, and ammonium transport in the FCW1 strain, adding to the theory that this strain may be helpful in treating kidney stones. This study revealed that the strain FCW1 might be an excellent potential probiotic in developing fermented coconut beverages and treating and preventing kidney stone disease.

The probiotic and immunomodulation effects of Limosilactobacillus reuteri RGW1 isolated from calf feces

Introduction

Limosilactobacillus reuteri is a gut symbiont with multiple remarkable beneficial effects on host health, and members of L. reuteri are valuable probiotic agents. However, L. reuteri showed obvious host specificity.

Methods

In our study, a novel L. reuteri RGW1 was isolated from feces of healthy calves, and its potential as a probiotic candidate were assessed, by combining in vitro, in vivo experiments and genomic analysis.

Results and discussion

RGW1 was sensitive to all the antibiotics tested, and it did not contain any virulence factor-coding genes. This isolate showed good tolerance to acid (pH 3.0), 0.3% bile salt, and simulated gastric fluid. Moreover, this isolate showed a high hydrophobicity index (73.7 ± 4.6%) and was able to adhere to Caco-2 cells, and antagonize Escherichia coli F5. Treatment of LPS-induced mice with RGW1 elevated TGF-β and IL-10 levels, while RGW1 cell-free supernatant (RCS) decreased TNF-α levels in the sera. Both RGW1 and RCS increased the villus height and villus height/crypt depth ratio of colon. Genomic analysis revealed the mechanism of the probiotic properties described above, and identified the capacity of RGW1 to biosynthesize L-lysine, folate, cobalamin and reuterin de novo. Our study demonstrated the novel bovine origin L. reuteri RGW1 had multiple probiotic characteristics and immunomodulation effects, and provided a deeper understanding of the relationship between these probiotic properties and genetic features.

Efficacy of zinc oxide nanoparticles and Bifidobacterium bifidum Extraction on anaerobic bacteria isolated from patients with diarrhea

Infectious acute diarrhea may be prevented with probiotics; because they make up the majority of the colonic flora in breastfed newborns and are likely to contribute to the lower incidence of diarrhea in this population, Bifidobacteria are particularly appealing as probiotics agents. The present study was designed to identify anaerobic bacteria, especially C. difficile the main reason for dysentery associated with antibiotics. Detect the ability of each ZnoNPs and B. bifidum to inhibit bacterial growth. During the period from March to October 2019, (100) children and adults who came to Salah al-deen hospital in Tikrit city participated in the study under the supervision of a physician. All samples were transported using a carry Blair if late one or two hours after collection and culturing. The collected models were also cultured on Xylose Lysine Deoxycholate agar, Salmonella Shigella agar, Eosin methylene blue agar, and MacConkey agar. For initiated diagnoses of the Enterobacteriaceae, Blood agar is used to detect beta-hemolytic isolates, recover enteric bacteria other than Enterobacteriaceae, and evaluate the results of oxidase tests. To diagnose bacterium kinds, biochemical reactions and motility tests were used. Impact of ZnoNPs, and B. bifidum antibiotic In vitro. The results of 100 dysentery feces samples were obtained into (60%) samples for males and (40%) for females. Eighty-two positively impacted anaerobically on growth media like Clostridium complicate agar and MacConkey agar (18%) other than bacteria. In contrast, negative samples revealed 10 (55.56 percent) samples for males and 8 (44.44 percent) samples for females. The same stool samples were taken and cultured on Clostridium difficile agar and MacConkey agar under anaerobic and ideal incubation conditions. 15% and 67% of isolates appeared on MacConkey agar of the total number of samples, while 18% showed negative growth. Finally, Zn NPs showed their ability to inhibit Clostridium complicated segregate lean on the condensation 5 mg/ml, and it caused the inhibitory effect on Clostridium to complicate by 10-22 of the diameter of inhibition. The Inhibition Zone Dimeter ranged from 8 to 25 mm for isolates when condensation was utilized at 2.5 mg/ml. According to the findings, the widths of the inhibitory zones for isolates of C. difficile containing B. bifidum supernatant mg/ml ranged from 9 to 24 mm. Keywords: Zinc oxide nanoparticles, Probiotic, Bifidobacterium bifidum, Clostridium difficile

Can probiotics mitigate age-related neuroinflammation leading to improved cognitive outcomes?

Changes in brain structure and cognitive function are a natural part of aging; however, in some cases these changes are more severe resulting in mild cognitive impairment (MCI) or Alzheimer's disease (AD). Evidence is mounting to show that neuroinflammation is an underlying risk factor for neurodegenerative disease progression. Age-related neuroinflammation does not appear to occur in isolation and is part of increased systemic inflammation, which may in turn be triggered by changes in the gut associated with aging. These include an increase in gut permeability, which allows immune triggering compounds into the body, and alterations in gut microbiota composition leading to dysbiosis. It therefore follows that, treatments that can maintain healthy gut function may reduce inflammation and protect against, or improve, symptoms of age-associated neurodegeneration. The aim of this mini review was to evaluate whether probiotics could be used for this purpose. The analysis concluded that there is preliminary evidence to suggest that specific probiotics may improve cognitive function, particularly in those with MCI; however, this is not yet convincing and larger, multilocation, studies focus on the effects of probiotics alone are required. In addition, studies that combine assessment of cognition alongside analysis of inflammatory biomarkers and gut function are needed. Immense gains could be made to the quality of life of the aging population should the hypothesis be proven to be correct.

Lactococcus lactis' Effect on the Intestinal Microbiota of Streptococcus agalactiae-Infected Zebrafish (Danio rerio)

Streptococcus agalactiae is a common pathogen in aquaculture that disrupts the balance of the intestinal microbiota and threatens fish health, causing enormous losses to the aquaculture industry. In this study, we isolated and screened a Lactococcus lactis KUST48 (LLK48) strain with antibacterial effect against S. agalactiae in vitro and used it as a potential probiotic to explore its therapeutic effect on zebrafish (Danio rerio) infected with S. agalactiae. This study divided zebrafish into 3 groups: control group, injected with phosphate-buffered saline; infection group, injected with S. agalactiae; and treatment group, treated with LLK48 after S. agalactiae injection. Then, the 16S rRNA gene sequences of the intestinal microbiota of these 3 groups were sequenced using Illumina high-throughput sequencing technology. The results showed that the relative abundance of intestinal bacteria was significantly decreased in the infection group, and a high relative abundance of S. agalactiae was observed. The relative abundance of the intestinal microbiota was increased in the treatment group, with a decrease in the relative abundance of S. agalactiae compared to that in the control group. In the Cluster of Orthologous Groups of proteins function classification, the relative abundance of each biological function in the infection group was significantly lower than that of the control and treatment groups, showing that LLK48 has a positive therapeutic effect on zebrafish infected with S. agalactiae. This study provides a foundation for exploring the pathogenic mechanism of S. agalactiae on fish and their intestinal symbionts, and also presents a new approach for the treatment of S. agalactiae infections in fish aquaculture systems. IMPORTANCE L. lactis KUST48 (LLK48) with a bacteriostatic effect against S. agalactiae was isolated from tilapia intestinal tracts. S. agalactiae infection significantly reduced the relative abundance of intestinal bacteria and various physiological functions in zebrafish intestines. LLK48 demonstrated infection and subsequent therapeutic effects on the S. agalactiae infection in the zebrafish intestine. Therefore, the potential probiotic LLK48 can be considered as a therapeutic treatment for S. agalactiae infections in aquaculture, which can reduce the use of antibiotics and help maintain fish health.

Exopolysaccharide of Enterococcus faecium L15 promotes the osteogenic differentiation of human dental pulp stem cells via p38 MAPK pathway

Background

Bone has important functions in the body. Several researchers have reported that the polysaccharides and lipopolysaccharide derived from microbes can promote osteogenic differentiation of stem cells. Enterococcus faecium, a lactic acid bacterium (LAB), produces several bioactive metabolites and has been widely applied in the food and nutraceutical industries. The exopolysaccharide (EPS) from LAB has also been extensively examined for its postbiotic effects and for its in vivo and in vitro functionalities. However, studies on promoting bone differentiation using polysaccharides from LAB are lacking. Therefore, the purpose of this study was to investigate the effect of E. faecium L15 extract and EPS on osteogenic differentiation of human dental pulp stem cells (hDPSCs) and to identify the underlying mechanisms.

Methods

hDPSCs were obtained from dental pulp tissue, and L15 extract and EPS were isolated from L15. Gene and protein expression of the osteogenic differentiation markers were analyzed with qPCR and western blotting and the possible signaling pathways were also investigated using western blotting. Osteogenic differentiation potential was examined by alkaline phosphatase (ALP) staining and alizarin red s (ARS) staining. In addition, osteogenic differentiation potential of L15 EPS was explored in ex vivo culture of neonate murine calvaria.

Results

The calcium deposition and ALP activity were enhanced by addition of L15 extract or EPS. The expression levels of RUNX2, ALP, and COL1A1 mRNA and the protein expression levels of RUNX2, ALP, and BMP4 were increased in hDPSCs treated with the L15 extract or EPS. The L15 EPS treatment enhanced phosphorylation of the p38 mitogen-activated protein kinase (MAPK). The L15 EPS-induced increases in RUNX2, ALP, and BMP4 expression were suppressed by the p38 MAPK inhibitor SB203580. The promoting effect of L15 EPS on osteogenic differentiation was not only seen in hDPSCs, but also in osteoblast precursors. ALP activity and the expression of RUNX2, ALP, and COL1A1 increased in the L15 EPS-treated osteoblast precursors. In addition, L15 EPS increased bone thickness of neonate murine calvaria in ex vivo culture.

Conclusions

The stimulatory effect of L15 extract and EPS on osteogenic differentiation occurred through the p38 MAPK pathway, and L15 EPS enhanced new bone formation in neonate murine calvaria. These data suggest that L15 EPS has therapeutic potential applicable to bone regeneration.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03151-0.

Insights into the Microbiological and Physicochemical Properties of Bio-Frozen Yoghurt Made with Probiotic Strains in Combination with Jerusalem Artichoke Tubers Powder

Frozen yoghurt is a refreshing and nutritious dessert, with or without the flavour that combines the texture of ice cream and yoghurt. Several previous studies have been conducted on Jerusalem artichoke tubers due to their components, which contain inulin compounds and other nutrients with beneficial properties of fresh yoghurt. However, limited studies explored the potential benefits of the addition of Jerusalem artichoke tuber powder as a fat replacer on the physicochemical properties and survival of probiotics in frozen yoghurt. In this respect, the aim of this study was to determine the effect of Jerusalem artichoke tuber powder (JATP) (0, 5, 10, 15, and 20% w/w) of the fat source used in the mix as a fat, and sugar replacer in frozen yoghurt production. The microbiological, physicochemical, textural, and sensory properties of frozen yoghurt were investigated. Samples with JATP contained viable counts of bifidobacterium bifidum BGN4 and Lactobacillus casei Lc-01 of 7 log cfu/g during 90 days of storage, as compared to the control sample. The highest viability of probiotics was obtained in the sample formulated with 10% JATP. The formulation of frozen yoghurt with JATP increased the acidity and enhanced the overrun. Compared with the control sample, the incorporation of JATP into frozen yoghurt increased the melting resistance, overrun, and viscosity of the frozen yoghurt. The addition of JATP up to 10% significantly increased sensory attributes. Collectively, the study concluded that the enrichment of frozen yoghurt with JATP up to 20% will provide consumers with health benefits and could be introduced to markets as functional frozen yoghurt.

Synergistic Effects of Probiotic Bifidobacterium Isolated from Chicken's Intestine in Combination with Polyvinylpyrrolidone on Reduction of Aflatoxin B1

Food contamination with aflatoxin is one of the most critical concerns of health professionals. One of the best ways to reduce aflatoxin content in food is probiotics. Therefore, this study was performed to isolate Bifidobacterium from the chick's intestine; evaluate its probiotic activities and its application with Polyvinylpyrrolidone (PVP) to reduce aflatoxin B₁ (AFB₁ ) in the medium were investigated. Samples were isolated from the chick's intestine, and Bifidobacterium was isolated and identified by biochemical and molecular methods. Next, the potential probiotic characterization was assessed. Afterward, the effect of selected isolate and PVP on reducing AFB₁ in the medium was studied using ELISA and HPLC. Biochemical and molecular evaluations indicated isolation of Bifidobacterium bifidum strain from chick's intestine. One of the B. bifidum strains was selected for the next steps, which showed potential probiotic characterization and the ability to reduce the concentration of AFB₁ in the medium (50% reduction). When used in combination with PVP showed synergistic effects in reducing the concentration of AFB₁ from the medium (up to 90%). In conclusion, it was found that selected B. bifidum strains and PVP could have synergistic effects in reducing AFB₁ toxin in a medium up to 90%.

A recombinant Bifidobacterium bifidum BGN4 strain expressing the streptococcal superoxide dismutase gene ameliorates inflammatory bowel disease

Background

Inflammatory bowel disease (IBD) is a gastrointestinal disease characterized by diarrhea, rectal bleeding, abdominal pain, and weight loss. Recombinant probiotics producing specific proteins with IBD therapeutic potential are currently considered novel drug substitutes. In this study, a Bifidobacterium bifidum BGN4-SK strain was designed to produce the antioxidant enzymes streptococcal superoxide dismutase (SOD) and lactobacillus catalase (CAT), and a B. bifidum BGN4-pBESIL10 strain was proposed to generate an anti-inflammatory cytokine, human interleukin (IL)-10. In vitro and in vivo efficacy of these genetically modified Bifidobacterium strains were evaluated for colitis amelioration.

Results

In a lipopolysaccharide (LPS)-stimulated HT-29 cell model, tumor necrosis factor (TNF)-α and IL-8 production was significantly suppressed in the B. bifidum BGN4-SK treatment, followed by B. bifidum BGN4-pBESIL10 treatment, when compared to the LPS-treated control. Synergistic effects on TNF-α suppression were also observed. In a dextran sodium sulphate (DSS)-induced colitis mouse model, B. bifidum BGN4-SK treatment significantly enhanced levels of antioxidant enzymes SOD, glutathione peroxidase (GSH-Px) and CAT, compared to the DSS-only group. B. bifidum BGN4-SK significantly ameliorated the symptoms of DSS-induced colitis, increased the expression of tight junction genes (claudin and ZO-1), and decreased pro-inflammatory cytokines IL-6, IL-1β and TNF-α.

Conclusions

These findings suggest that B. bifidum BGN4-SK ameliorated DSS-induced colitis by generating antioxidant enzymes, maintaining the epithelial barrier, and decreasing the production of pro-inflammatory cytokines. Although B. bifidum BGN4-pBESIL10 exerted anti-inflammatory effects in vitro, the enhancement of IL-10 production and alleviation of colitis were very limited.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12934-022-01840-2.

Bifidobacterium spp. as functional foods: A review of current status, challenges, and strategies

Members of Bifidobacterium are among the first microbes to colonize the human intestine naturally, their abundance and diversity in the colon are closely related to host health. Recently, the gut microbiota has been gradually proven to be crucial mediators of various metabolic processes between the external environment and the host. Therefore, the health-promoting benefits of Bifidobacterium spp. and their applications in food have gradually been widely concerned. The main purpose of this review is to comprehensively introduce general features, colonization methods, and safety of Bifidobacterium spp. in the human gut, highlighting its health benefits and industrial applications. On this basis, the existing limitations and scope for future research are also discussed. Bifidobacteria have beneficial effects on the host's digestive system, immune system, and nervous system. However, the first prerequisite for functioning is to have enough live bacteria before consumption and successfully colonize the colon after ingestion. At present, strain breeding, optimization (e.g., selecting acid and bile resistant strains, adaptive evolution, high cell density culture), and external protection technology (e.g., microencapsulation and protectants) are the main strategies to address these challenges in food application.

Bifidobacterium bifidum BGN4 Paraprobiotic Supplementation Alleviates Experimental Colitis by Maintaining Gut Barrier and Suppressing Nuclear Factor Kappa B Activation Signaling Molecules

Inflammatory bowel diseases, including Crohn's disease and ulcerative colitis, are characterized by chronic gastrointestinal inflammation with continuous relapse-remission cycles. This study aimed to evaluate the protective effect of Bifidobacterium bifidum BGN4 as a probiotic or paraprobiotic against dextran sulfate sodium (DSS)-induced colitis in mice. Ten-week-old female BALB/c mice were randomly divided into five groups. The control (CON) and DSS groups received oral gavage of PBS, whereas the live B. bifidum (LIVE), heat-killed B. bifidum BGN4 (HEAT), and lysozyme-treated B. bifidum BGN4 (LYSOZYME) groups received live B. bifidum BGN4, heat-killed B. bifidum BGN4, and lysozyme-treated B. bifidum BGN4, respectively, for 10 days, followed by DSS supply to induce colitis. The paraprobiotic (HEAT and LYSOZYME) groups had less body weight loss and colon length shortening than the DSS or LIVE groups. The LYSOZYME group exhibited better preserved intestinal barrier integrity than the LIVE group by upregulating gap junction protein expression possibly through activating NOD-like receptor family pyrin domain containing 6/caspase-1/interleukin (IL)-18 signaling. The LYSOZYME group showed downregulated proinflammatory molecules, including p-inhibitor of kappa B proteins alpha (IκBα), cycloxygenase 2 (COX2), IL-1β, and T-bet, whereas the expression of the regulatory T cell transcription factor, forkhead box P3 expression, was increased. The paraprobiotic groups showed distinct separation of microbiota distribution and improved inflammation-associated dysbiosis. These results suggest that B. bifidum BGN4 paraprobiotics, especially lysozyme-treated BGN4, have a preventive effect against DSS-induced colitis, impacting intestinal barrier integrity, inflammation, and dysbiosis.

Recent Development of Probiotic Bifidobacteria for Treating Human Diseases

Bifidobacterium is a non-spore-forming, Gram-positive, anaerobic probiotic actinobacterium and commonly found in the gut of infants and the uterine region of pregnant mothers. Like all probiotics, Bifidobacteria confer health benefits on the host when administered in adequate amounts, showing multifaceted probiotic effects. Examples include B. bifidum, B. breve, and B. longum, common Bifidobacterium strains employed to prevent and treat gastrointestinal disorders, including intestinal infections and cancers. Herein, we review the latest development in probiotic Bifidobacteria research, including studies on the therapeutic impact of Bifidobacterial species on human health and recent efforts in engineering Bifidobacterium. This review article would provide readers with a wholesome understanding of Bifidobacteria and its potentials to improve human health.

Exploring the universal healthy human gut microbiota around the World

The human gut holds a special place in the study of different microbial environments due to growing evidence that the gut microbiota is related to host health. However, despite extensive research, there is still a lack of knowledge about the core taxa forming the gut microbiota and, moreover, available information is biased towards western microbiomes in both genome databases and most core taxa studies. To tackle these limitations, we tested a database enrichment strategy and analyzed public datasets of whole-genome shotgun data, generated from 545 fecal samples, comprising three gradients of westernization. The NT database was selected as a baseline of biological diversity, subsequently being combined with various studies of interest related to the human microbiota. This enrichment strategy made it possible to improve classification capacity, compared to the original unenriched database, regarding the various lifestyles and populations studied. The effects of incomplete-taxonomy metagenome-assembled genomes on genome database enrichment were also examined, revealing that, while they are helpful, they should be used with caution depending on the taxonomic level of interest. Moreover, in terms of high prevalence, the core analysis revealed a conserved set of bacterial taxa in the healthy human gut microbiota worldwide, despite apparent lifestyle differences. Such taxa show a set of traits, metabolic roles, and ancestral status, making them suitable candidates for a hypothetical phylogenetic core of mutualistic microorganisms co-evolving with the human species.

Probiotics partially attenuate the severity of acute kidney injury through an immunomodulatory effect

Background

A healthy microbiome helps maintain the gut barrier and mucosal immune tolerance. Previously, we demonstrated that acute kidney injury (AKI) provoked dysbiosis, gut inflammation, and increased permeability. Here, we investigated the renoprotective effects of the probiotic Bifidobacterium bifidum BGN4 and the underlying mechanisms thereof.

Methods

C57BL/6 mice were subjected to bilateral renal ischemia-reperfusion injury (IRI) or sham operation. In the probiotic-treated group, BGN4 was administered by gavage once daily, starting 2 weeks before injury.

Results

Administration of BGN4 significantly increased gut microbiome diversity and prevented expansion of the Enterobacteriaceae and Bacteroidetes that were the hallmarks of AKI-induced dysbiosis. Further, BGN4 administration also significantly reduced other IRI-induced changes in the colon microenvironment, including effects on permeability, apoptosis of colon epithelial cells, and neutrophil and proinflammatory macrophage infiltration. Mononuclear cells co-cultured with BGN4 expressed significantly increased proportions of CD103⁺/CD11c⁺ and CD4⁺ CD25⁺ Treg cells, suggesting a direct immunomodulatory effect. BGN4 induced Treg expansion in colon, mesenteric lymph nodes (MNL), and kidney. BGN4 also reduced CX₃CR₁^intermediateLy6C^high monocyte infiltration and interleukin (IL)-17A suppression in the small intestine, which may have attenuated AKI severity, kidney IL-6 messenger RNA expression, and AKI-induced liver injury.

Conclusion

Prior supplementation with BGN4 significantly attenuated the severity of IRI and secondary liver injury. This renoprotective effect was associated with increased Foxp3 and reduced IL-17A expression in the colon, MNL, and kidney, suggesting that BGN4-induced immunomodulation might contribute to its renoprotective effects. Probiotics may therefore be a promising strategy to reduce AKI severity and/or remote organ injury.

Probiotics as Therapeutic Tools against Pathogenic Biofilms: Have We Found the Perfect Weapon?

Bacterial populations inhabiting a variety of natural and human-associated niches have the ability to grow in the form of biofilms. A large part of pathological chronic conditions, and essentially all the bacterial infections associated with implanted medical devices or prosthetics, are caused by microorganisms embedded in a matrix made of polysaccharides, proteins, and nucleic acids. Biofilm infections are generally characterized by a slow onset, mild symptoms, tendency to chronicity, and refractory response to antibiotic therapy. Even though the molecular mechanisms responsible for resistance to antimicrobial agents and host defenses have been deeply clarified, effective means to fight biofilms are still required. Lactic acid bacteria (LAB), used as probiotics, are emerging as powerful weapons to prevent adhesion, biofilm formation, and control overgrowth of pathogens. Hence, using probiotics or their metabolites to quench and interrupt bacterial communication and aggregation, and to interfere with biofilm formation and stability, might represent a new frontier in clinical microbiology and a valid alternative to antibiotic therapies. This review summarizes the current knowledge on the experimental and therapeutic applications of LAB to interfere with biofilm formation or disrupt the stability of pathogenic biofilms.

The effect of probiotic supplementation on systemic inflammation in dialysis patients

Background

Emerging evidence suggests that intestinal dysbiosis contributes to systemic inflammation and cardiovascular diseases in dialysis patients. The purpose of this study was to evaluate the effects of probiotic supplementation on various inflammatory parameters in hemodialysis (HD) patients.

Methods

Twenty-two patients with maintenance HD were enrolled. These patients were treated twice a day with 2.0 ×1010 colony forming units of a combination of Bifidobacterium bifidum BGN4 and Bifidobacterium longum BORI for 3 months. The microbiome and fecal short-chain fatty acids (SCFAs) were analyzed. The percentages of CD14+ CD16+ proinflammatory monocytes and CD4+ CD25+ regulatory T-cells (Tregs) before and after probiotic supplementation were determined by flow cytometry. Serum levels of calprotectin and cytokine responses upon lipopolysaccharide (LPS) challenge were compared before and after probiotic supplementation.

Results

Fecal SCFAs increased significantly after probiotic supplementation. Serum levels of calprotectin and interleukin 6 upon LPS stimulation significantly decreased. The anti-inflammatory effects of probiotics were associated with a significant increase in the percentage of CD4+ CD25+ Tregs (3.5% vs. 8.6%, p < 0.05) and also with a decrease of CD14+ CD16+ proinflammatory monocytes (310/mm2 vs. 194/mm2, p < 0.05).

Conclusion

Probiotic supplementation reduced systemic inflammatory responses in HD patients and this effect was associated with an increase in Tregs and a decrease in proinflammatory monocytes. Hence, targeting intestinal dysbiosis might be a novel strategy for decreasing inflammation and cardiovascular risks in HD patients.

Effects of different initial pH values on freeze-drying resistance of Lactiplantibacillus plantarum LIP-1 based on transcriptomics and proteomics

The growth and the resistance to adverse environments of lactic acid bacteria would be affected by adjusting the initial pH of the medium. In order to explore the effect of changing the initial pH of culture medium on the freeze-drying survival rate of the Lactiplantibacillus plantarum LIP-1, the effect of initial pH on cell membrane fatty acid composition and key enzyme activity were mainly determined, and the internal mechanism was studied by transcriptomics and proteomics methods. We found that compared with initial pH 7.4 group, initial pH 6.8 group could improve the freeze-drying survival rate of the L. plantarum LIP-1. It was possibly due to the lactate dehydrogenase (LDH) was upregulated in the initial pH6.8 group, which led to a rapid decrease in culture pH. To reduce the inhibitory effect of long-term acid environment on growth, the strain upregulated the expression of fatty acid synthesis-related genes and proteins, promoted the relative content of cyclopropane and unsaturated fatty acids, improved integrity of the cell membranes. The adjustment of fatty acid composition maintained the integrity of the cell membrane in a freeze-drying environment to improve the freeze-drying survival rate of the initial pH6.8 group. In addition, the long-term acid environment stimulated a cross-stress tolerance mechanism that significantly upregulated the expression of a cold stress protein. The results indicated that the optimal initial pH of the medium could improve the ability of L. plantarum LIP-1 to resist freeze-drying.

Lysed and disrupted Bifidobacterium bifidum BGN4 cells promote anti-inflammatory activities in lipopolysaccharide-stimulated RAW 264.7 cells

Bifidobacterium bifidum BGN4 has been shown to improve the immune system by regulating interleukin (IL)-6 in RAW 264.7 macrophage cells. In this study, the dead cells of B. bifidum BGN4 were produced by enzymatic and physical processing to enhance the inhibition properties of pro-inflammatory cytokines using lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Notably, the secretion levels of cytokines such as interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α were decreased by the cell-wall disrupted extracts compared to heat-killed cells. The result suggests that the exposed interior-surface of B. bifidum BGN4 has a potential ability to regulate the immune-responses in the gastrointestinal tract due to major substances in inside-cell wall such as peptidoglycan and teichoic acids. In conclusion, the lysed and disrupted cells from the inside out of B. bifidum BGN4 have anti-inflammatory properties as paraprobiotic agents to control chronic inflammatory related-diseases.

Fabrication of fish gelatin / sodium alginate double network gels for encapsulation of probiotics

BACKGROUND

To improve the environmental resistance of probiotics, and particularly their survival in the gastrointestinal environment, a fish gelatin (FG) / sodium alginate (SA) double network gelation (FSDN) was developed to encapsulate them. Thermal treatment and calcium ion inducement were adopted to fabricate fish gelatin and sodium alginate gels. It was feasible to scale up this process. The effects of FG concentration (0-60 g/L) on FSDN properties, including morphology, water-holding capacity, and encapsulation efficiency were evaluated.

RESULTS

The results indicated that the addition of FG could improve the transparency, rehydration, and water-holding capacity of FSDN. Scanning electronic microscope (SEM) images revealed that FSDN had a denser and more complete structure than SA. Encapsulation efficiency improved from 15.85% to 91.91% as the FG concentration ranged from 0 to 50 g/L. Bifidobacterium longum embedded by FSDN showed better thermal stability than when it was free. Compared with bare probiotics (1.7%), the encapsulated ones exhibited higher viability (above 15%) in simulated gastric fluid.

CONCLUSION

In conclusion, interpenetrating FSDN is an effective barrier constituent and could achieve the targeted delivery of probiotics. It is a potential new delivery carrier for the oral administration of probiotics. © 2021 Society of Chemical Industry.

Colonization Ability and Impact on Human Gut Microbiota of Foodborne Microbes From Traditional or Probiotic-Added Fermented Foods: A Systematic Review

A large subset of fermented foods act as vehicles of live environmental microbes, which often contribute food quality assets to the overall diet, such as health-associated microbial metabolites. Foodborne microorganisms also carry the potential to interact with the human gut microbiome via the food chain. However, scientific results describing the microbial flow connecting such different microbiomes as well as their impact on human health, are still fragmented. The aim of this systematic review is to provide a knowledge-base about the scientific literature addressing the connection between foodborne and gut microbiomes, as well as to identify gaps where more research is needed to clarify and map gut microorganisms originating from fermented foods, either traditional or added with probiotics, their possible impact on human gut microbiota composition and to which extent foodborne microbes might be able to colonize the gut environment. An additional aim was also to highlight experimental approaches and study designs which could be better standardized to improve comparative analysis of published datasets. Overall, the results presented in this systematic review suggest that a complex interplay between food and gut microbiota is indeed occurring, although the possible mechanisms for this interaction, as well as how it can impact human health, still remain a puzzling picture. Further research employing standardized and trans-disciplinary approaches aimed at understanding how fermented foods can be tailored to positively influence human gut microbiota and, in turn, host health, are therefore of pivotal importance.

The Antioxidant, Anti-Diabetic, and Anti-Adipogenesis Potential and Probiotic Properties of Lactic Acid Bacteria Isolated from Human and Fermented Foods

In this study, lactic acid bacteria (LAB) strains derived from human and fermented food sources were examined to identify their properties related to obesity, as well as establish their safety and stability as probiotics. LAB (Lacticaseibacillus rhamnosus MG4502, Lactobacillus gasseri MG4524, Limosilactobacillus reuteri MG5149, and Weissella cibaria MG5285) exhibited antioxidant activity through DPPH (>26.1%) and ABTS (>40.1%) radical scavenging assays and α-glucosidase inhibitory activities (>60.3%), respectively. The LAB strains promoted anti-adipogenesis by reducing lipid accumulation in 3T3-L1 cells by Oil Red O staining (>70.3%). In addition, we found that these LAB strains were resistant to simulated gastric and intestinal fluids (pH 3, 4, 7, and 8) and showed potential for health promotion, based on hemolysis, cell adhesion, antibiotic susceptibility, and enzyme production. Thus, LAB may be used as probiotic ingredients with beneficial effects.

Fermentation Profile and Probiotic-Related Characteristics of Bifidobacterium longum MC-42

This article presents new data on Bifidobacterium longum MC-42—a strain that has been actively used for the preparation of commercial dairy products in Russia for almost 40 years. It was demonstrated that this strain possesses high activities of β-galactosidase, α-glucosidase, and leucine arylaminidase; inhibits the growth of pathogens such as Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli; and can efficiently remove cholesterol from the cultural medium. The resistance of B. longum MC-42 determined for 15 commonly used antibiotics was in agreement with those previously reported for Bifidobacterium spp. The absence of frequently transmittable antibiotic resistance genes in the genome and the lack of undesirable activity of β-glucuronidase proved the safe use of B. longum МС-42 as a probiotic and starter culture. Additionally, the impact of two growth-promoting additives—yeast extract or milk protein hydrolysate containing supplementation—on the B. longum MC-42 fermentation profile was assessed. The introduction of these additives increases the maximum attainable viable cell count by orders of magnitude, significantly changed the profile of aminopeptidase activities in extracellular extracts, and influenced the antioxidant and antihypertensive properties of the obtained fermented products.

Enterococcus faecium L-15 Extract Enhances the Self-Renewal and Proliferation of Mouse Skin-Derived Precursor Cells

Lactic acid bacteria (LAB) in the gastrointestinal tract have beneficial health effects. LAB activate the proliferation of intestinal stem cells and speed the recovery of damaged intestinal cells, but little is known about effect of LAB on other adult stem cells. In this study, a cell-free extract of Enterococcus faecium L-15 (L15) was exposed to mouse skin-derived precursor cells (SKPs), and the changes in characteristics associated with proliferation and self-renewal capacity were investigated. L15 increased the size of the spheres and the proliferation rate of SKPs. Cell cycle analysis revealed that cells in the S-phase increased after treatment with L15. In the L15-treated group, the total number of spheres significantly increased. The expression level of pluripotency marker genes also increased, while the mesenchymal lineage-related differentiation marker genes significantly decreased in the L15-treated group. The PI3K/Akt signaling pathway was activated by L15 in SKPs. These results indicate that L15 enhances proliferation and self-renewal of SKPs and may be used as a supplement for stem cell maintenance or application of stem cell therapy. This is the first report to investigate the functional effects of E. faecium on the proliferation and self-renewal capacity of SKPs.

Probiotics for the Chemoprotective Role Against the Toxic Effect of Cancer Chemotherapy

BACKGROUND

The processes of chemo- and radiation therapy-based clinical management of different types of cancers are associated with toxicity and side effects of chemotherapeutic agents. So, there is always an unmet need to explore agents to reduce such risk factors. Among these, natural products have generated much attention because of their potent antioxidant and antitumor effects. In the past, some breakthrough outcomes established that various bacteria in the human intestinal gut are bearing growth-promoting attributes and suppressing the conversion of pro-carcinogens into carcinogens. Hence, probiotics integrated approaches are nowadays being explored as rationalized therapeutics in the clinical management of cancer.

METHODS

Here, published literature was explored to review chemoprotective roles of probiotics against toxic and side effects of chemotherapeutics.

RESULTS

Apart from excellent anti-cancer abilities, probiotics are bearing and alleviate toxicity and side effects of chemotherapeutics, with a high degree of safety and efficiency.

CONCLUSION

Preclinical and clinical evidence suggested that due to the chemoprotective roles of probiotics against side effects and toxicity of chemotherapeutics, their integration in chemotherapy would be a judicious approach.

Anticancer effects of bifidobacteria on colon cancer cell lines

Background

Colorectal cancer (CRC), with a growing incidence trend worldwide, is resistant to apoptosis and has uncontrolled proliferation. It is recently reported that probiotic microorganisms exert anticancer effects. The genus Bifidobacterium, one of the dominant bacterial populations in the gastrointestinal tract, has received increasing attention because of widespread interest in using it as health-promoting microorganisms. Therefore, the present study aimed to assess the apoptotic effects of some bifidobacteria species on colon cancer cell lines.

Methods

The cytotoxicity evaluations performed using MTT assay and FACS-flow cytometry tests. Also, the effects of five species of bifidobacteria secretion metabolites on the expression level of anti- or pro-apoptotic genes including BAD, Bcl-2, Caspase-3, Caspase-8, Caspase-9, and Fas-R studied by real-time polymerase chain reaction (RT-PCR) method.

Results

The cell-free supernatant of all studied bifidobacteria significantly decreased the survival rates of colon cancer cells compared with control groups. Flow cytometric and RT-PCR results indicated that apoptosis is induced by bifidobacteria secretion metabolites and the mechanism for the action of bifidobacteria species in CRC prevention could be down-regulation and up-regulation of anti-apoptotic and, pro-apoptotic genes.

Conclusions

In the present study, different bifidobacteria species showed anticancer activity on colorectal cancer cells through down-regulation and up-regulation of anti-apoptotic and pro-apoptotic genes. However, further studies are required to clarify the exact mechanism of apoptosis induction by bifidobacteria species.

Probiotics in the dairy industry-Advances and opportunities

The past two decades have witnessed a global surge in the application of probiotics as functional ingredients in food, animal feed, and pharmaceutical products. Among food industries, the dairy industry is the largest sector where probiotics are employed in a number of dairy products including sour/fermented milk, yogurt, cheese, butter/cream, ice cream, and infant formula. These probiotics are either used as starter culture alone or in combination with traditional starters, or incorporated into dairy products following fermentation, where their presence imparts many functional characteristics to the product (for instance, improved aroma, taste, and textural characteristics), in addition to conferring many health-promoting properties. However, there are still many challenges related to the stability and functionality of probiotics in dairy products. This review highlights the advances, opportunities, and challenges of application of probiotics in dairy industries. Benefits imparted by probiotics to dairy products including their role in physicochemical characteristics and nutritional properties (clinical and functional perspective) are also discussed. We transcend the traditional concept of the application of probiotics in dairy products and discuss paraprobiotics and postbiotics as a newly emerged concept in the field of probiotics in a particular relation to the dairy industry. Some potential applications of paraprobiotics and postbiotics in dairy products as functional ingredients for the development of functional dairy products with health-promoting properties are briefly elucidated.

Antioxidant and Anti-Inflammatory Properties of Recombinant Bifidobacterium bifidum BGN4 Expressing Antioxidant Enzymes

Bifidobacterium bifidum BGN4-SK (BGN4-SK), a recombinant strain which was constructed from B. bifidum BGN4 (BGN4) to produce superoxide dismutase (SOD) and catalase, was analyzed to determine its antioxidant and anti-inflammatory properties in vitro. Culture conditions were determined to maximize the SOD and catalase activities of BGN4-SK. The viability, intracellular radical oxygen species (ROS) levels, intracellular antioxidant enzyme activities, and pro-inflammatory cytokine levels were determined to evaluate the antioxidant and anti-inflammatory activities of BGN4-SK in human intestinal epithelial cells (HT-29) and murine macrophage cells (RAW 264.7). Antioxidant enzymes (SOD and catalase) were produced at the highest levels when BGN4-SK was cultured for 24 h in a medium containing 500 μM MnSO₄ and 30 μM hematin, with glucose as the carbon source. The viability and intracellular antioxidant enzyme activities of H₂O₂-stimulated HT-29 treated with BGN4-SK were significantly higher (p < 0.05) than those of cells treated with BGN4. The intracellular ROS levels of H₂O₂-stimulated HT-29 cells treated with BGN4-SK were significantly lower (p < 0.05) than those of cells treated with BGN4. BGN4-SK more significantly suppressed the production of interleukin (IL)-6 (p < 0.05), tumor necrosis factor-α (p < 0.01), and IL-8 (p < 0.05) in lipopolysaccharide (LPS)-stimulated HT-29 and LPS-stimulated RAW 264.7 cells compared to BGN4. These results suggest that BGN4-SK may have enhanced antioxidant activities against oxidative stress in H₂O₂-stimulated HT-29 cells and enhanced anti-inflammatory activities in LPS-stimulated HT-29 and RAW 264.7 cells.

Production of biologically active human interleukin-10 by Bifidobacterium bifidum BGN4

BACKGROUND

Bifidobacterium spp. are representative probiotics that play an important role in the health of their hosts. Among various Bifidobacterium spp., B. bifidum BGN4 exhibits relatively high cell adhesion to colonic cells and has been reported to have various in vivo and in vitro bio functionalities (e.g., anti-allergic effect, anti-cancer effect, and modulatory effects on immune cells). Interleukin-10 (IL-10) has emerged as a major suppressor of immune response in macrophages and other antigen presenting cells and plays an essential role in the regulation and resolution of inflammation. In this study, recombinant B. bifidum BGN4 [pBESIL10] was developed to deliver human IL-10 effectively to the intestines.

RESULTS

The vector pBESIL10 was constructed by cloning the human IL-10 gene under a gap promoter and signal peptide from Bifidobacterium spp. into the E. coli-Bifidobacterium shuttle vector pBES2. The secreted human IL-10 from B. bifidum BGN4 [pBESIL10] was analyzed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), Western Blotting, and enzyme-linked immunosorbent assay (ELISA). More than 1,473 ± 300 ng/mL (n = 4) of human IL-10 was obtained in the cell free culture supernatant of B. bifidum BGN4 [pBESIL10]. This productivity is significantly higher than other previously reported human IL-10 level from food grade bacteria. In vitro functional evaluation of the cell free culture supernatant of B. bifidum BGN4 [pBESIL10] revealed significantly inhibited interleukin-6 (IL-6) production in lipopolysaccharide (LPS)-induced Raw 264.7 cells (n = 6, p < 0.0001) and interleukin-8 (IL-8) production in LPS-induced HT-29 cells (n = 6, p < 0.01) or TNFα-induced HT-29 cells (n = 6, p < 0.001).

CONCLUSION

B. bifidum BGN4 [pBESIL10] efficiently produces and secretes significant amounts of biologically active human IL-10. The human IL-10 production level in this study is the highest of all human IL-10 production reported to date. Further research should be pursued to evaluate B. bifidum BGN4 [pBESIL10] producing IL-10 as a treatment for various inflammation-related diseases, including inflammatory bowel disease, rheumatoid arthritis, allergic asthma, and cancer immunotherapy.

Probiotics and Gut Health in Athletes

PURPOSE OF REVIEW

To provide a focused analysis of the challenges to gut health in athletes and examine recent research aimed at determining the impact of probiotics on preventing gastrointestinal (GI) symptoms and loss of barrier function in athletes.

RECENT FINDINGS

Frequency and severity of GI symptoms during training or competition were reduced by approximately one-third in studies demonstrating efficacy. Improvement of GI symptoms with probiotic supplementation was measured in both single-strain Lactobacillus and multi-strain Lactobacillus and Bifidobacterim probiotics, while improvement in gut barrier function was only measured for multi-strain probiotics. Likelihood of efficacy increased with duration of supplementation. The greatest efficacy for reducing GI symptom frequency and severity, as well as improving or preserving gut barrier function during exercise training and competition, appears to be for multi-strain Lactobacillus and Bifidobacterium probiotic cocktails supplemented for at least 11 weeks.

Improving the freeze-drying survival rate of Lactobacillus plantarum LIP-1 by increasing biofilm formation based on adjusting the composition of buffer salts in medium

Lactic acid bacteria can improve their resistance to adverse environments through the formation of biofilm. This study found that adding different buffer salts in culture medium had a great impact on the freeze-drying survival rate of the Lactobacillus plantarum LIP-1, which could be linked to biofilm formation. Transcriptome data showed that potassium ions in buffer salt increased the expression of the luxS gene in the LuxS/autoinducer-2 (AI-2) quorum sensing system and increase synthesis of the quorum sensing signal AI-2. The AI-2 signal molecules up-regulated the cysE gene, which helps to promote biofilm formation. By adding a biofilm inhibitor, d-galactose, and performing a real-time quantitative polymerase chain reaction experiment, we found that d-galactose could down-regulated the luxS and cysE genes, reduced biofilm formation, and decreased the freeze-drying survival rate. The results of this study showed that promoting biofilm formation using appropriate buffer salts may lead to better freeze-drying survival rates.

Role of probiotics in patients with colorectal cancer: a systematic review protocol of randomised controlled trial studies

INTRODUCTION

Colorectal cancer is one of the leading causes of cancer-related morbidity worldwide and it has been reported to be associated with poor lifestyle habits which include excess tobacco and alcohol intake as well as genetics and age factors. Probiotics such as the lactic acid bacteria and Bifidobacterium as well as probiotic containing foods (kombucha, kefir, miso etc) have received lots of attention as anticancer agents for prevention and treatment. The effects of the administration of probiotics to patients with colorectal cancer is the primary goal of this systematic review. The overall aim is to assess how the use of probiotics in patients with colorectal cancer helps in the management of colorectal cancer and its effect on the diversity of gut microbiota. The final systematic review will provide a comprehensive evidence base for the use and efficacy of probiotics in patient with colorectal cancer care.

METHODS AND ANALYSIS

The systematic review, will be conducted by extensively searching different databases such as PubMed, Web of Science, Scopus, Wiley and ProQuest to identify randomised controlled trials (with no time frame) which relate to the administration of probiotics to patients with colorectal cancer. The search strategy will include words like colorectal cancer, probiotics, Bifidobacterium, clinical trials etc. A systematic search of databases was performed between 17 and 20 January 2020. Two reviewers will independently review the studies and also search the reference lists of the eligible studies to obtain more references. Data will be extracted from the eligible studies using standardised data extraction form. After assessing the risk of bias, qualitative analysis will be used to synthesise the systematic review.

ETHICS AND DISSEMINATION

This is a protocol for a systematic review; therefore, it doesn't require any ethics approval. We intend to disseminate the protocol in a peer reviewed journal.

Whole genome sequence analysis and in vitro probiotic characteristics of a Lactobacillus strain Lactobacillus paracasei ZFM54

AIM

The aim was to identify a Lactobacillus strain with potential probiotic characteristics by whole-genome sequence analysis and in vitro experimental studies.

METHODS AND RESULTS

The whole-genome sequencing was carried out using PacBio RSII sequencing method and Illumina's paired-end sequencing technology. Gene prediction and annotation were achieved using GlimmerVersion 3.02 and NCBI prokaryotic Genome Annotation Pipeline. Identification was done by biochemical tests and 16S rRNA sequence analysis. mega 6 software was used to build phylogenetic tree. Antagonism against pathogen was determined by agar well diffusion method. Resistance and stability to bile, simulated gastric acid, different salt concentration and thermostability were investigated. Hydrophobicity assay, aggregation assay and anti-oxidation assay were performed to check further probiotic traits. Finally antibiotic susceptibility and acute oral toxicity of the strain in mice were investigated to check its safety status. The strain showed >99% similarity to Lactobacillus paracasei which was further confirmed by biochemical tests. It significantly inhibited pathogens in agar well diffusion assay. It showed tolerance to simulated gastric acid (pH 3), 0·3% bile salt and 10% NaCl. Significant hydrophobic, aggregation and anti-oxidizing activities were observed. No resistance to antibiotics tested was observed and no adverse effects during acute oral toxicity in mice were detected.

CONCLUSIONS

Lactobacillus paracasei ZFM 54, a new and safe Lactobacillus strain was identified with numerous probiotic-associated genes and characteristics confirmed by experimental studies.

SIGNIFICANCE AND IMPACT OF THE STUDY

A new probiotic strain has been identified which is highly stable, safe and suitable to be used in health and food industries.

Recent Advancements in the Development of Modern Probiotics for Restoring Human Gut Microbiome Dysbiosis

A healthy gut is predominantly occupied by bacteria which play a vital role in nutrition and health. Any change in normal gut homeostasis imposes gut dysbiosis. So far, efforts have been made to mitigate the gastrointestinal symptoms using modern day probiotics. The majority of the probiotics strains used currently belong to the genera Lactobacillus, Clostridium, Bifidobacterium and Streptococcus. Recent advancements in culturomics by implementing newer techniques coupled with the use of gnotobiotic animal models provide a subtle ground to develop novel host specific probiotics therapies. In this review article, the recent advances in the development of microbe-based therapies which can now be implemented to treat a wide spectrum of diseases have been discussed. However, these probiotics are not classified as drugs and there is a lack of stringent law enforcement to protect the end users against the pseudo-probiotic products. While modern probiotics hold strong promise for the future, more rigorous regulations are needed to develop genuine probiotic products and characterize novel probiotics using the latest research and technology. This article also highlights the possibility of reducing antibiotic usage by utilizing probiotics developed using the latest concepts of syn and ecobiotics.

In vivo evaluation of the anti-obesity effects of combinations of Monascus pigment derivatives

The prevention and treatment of obesity using naturally derived compounds is desirable in terms of marketing and safety in the nutraceutical and functional food markets. One of the noticeable effects of Monascus pigment derivatives is the inhibition/deactivation of lipid metabolism. Our earlier studies reported that threonine (Thr), tryptophan (Trp), and 2-(p-tolyl)-ethylamine (TEA) derivatives of Monascus pigment showed cholesterol-lowering, lipase-inhibitory, and adipogenic differentiation-inhibitory activities, respectively. In this work, we investigated the in vivo anti-obesity effects of a combination of Thr, Trp and TEA derivatives. C57BL/6 mice were fed a high-fat diet (HFD) and simultaneously administered one of three 1 : 1 mixtures of Thr, Trp, and TEA derivatives. After 10 weeks of feeding, the weight gains of mice fed with three combined derivatives decreased by 20.3-37.9%, compared to mice fed the HFD. The epididymal adipose tissue (EAT) weights of mice fed with the combined derivatives decreased by 42.3-60.5% compared to the HFD group, and their EAT size decreased. Transverse micro-CT imaging revealed reduction of the subcutaneous and visceral fat layers of test mice. Our results confirm that Monascus-fermented pigment derivatives have in vivo anti-obesity effects and their combinations provide a higher efficacy in the reduction of body weight and EAT weights as well as lipid accumulation in mice. The key to accomplishing high anti-obesity effect was combining Thr and Trp derivatives, which provide higher effectiveness than other combined derivatives. These observations offer a potential use of Monascus pigment derivatives as a therapeutic approach to prevention and/or treatment of obesity.

The Combined Usage of β-Cyclodextrin and Milk Proteins in Microencapsulation of Bifidobacterium bifidum BB-12

The present study aimed to determine the effects of combined usage of β-cyclodextrin with whey protein isolate and sodium caseinate on the microencapsulation of Bifidobacterium bifidum-BB12 by spray drying.From the results, the highest count of B. bifidum was provided by whey protein isolate as 8.62 log CFU/g. The increasing concentration of β-cyclodextrin considerably increases gastric and intestinal resistance to B. bifidum cells. In the gastric and intestinal test, the highest protection was determined in whey protein isolate substituted with 10% β-cyclodextrin with reduction rates of 0.98 and 3.30%, respectively. Moreover, free cells did not survive in the same gastric conditions. The lowest hygroscopicity was determined in whey protein isolate as 8.57%. It must be noted that increasing β-cyclodextrin concentration in carrier material combination led to an increase in hygroscopicity of microcapsules. In general, substitution with β-cyclodextrin increased the particle size of microparticles, and microcapsules produced with whey protein isolate had a smaller size than that of sodium caseinate.

Modification of Immunological Parameters, Oxidative Stress Markers, Mood Symptoms, and Well-Being Status in CFS Patients after Probiotic Intake: Observations from a Pilot Study

The present study discusses about the effects of a combination of probiotics able to stimulate the immune system of patients affected by Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). To this purpose, patients diagnosed according to Fukuda's criteria and treated with probiotics were analyzed by means of clinical and laboratory evaluations, before and after probiotic administrations. Probiotics were selected considering the possible pathogenic mechanisms of ME/CFS syndrome, which has been associated with an impaired immune response, dysregulation of Th1/Th2 ratio, and high oxidative stress with exhaustion of antioxidant reserve due to severe mitochondrial dysfunction. Immune and oxidative dysfunction could be related with the gastrointestinal (GI) chronic low-grade inflammation in the lamina propria and intestinal mucosal surface associated with dysbiosis, leaky gut, bacterial translocation, and immune and oxidative dysfunction. Literature data demonstrate that bacterial species are able to modulate the functions of the immune and oxidative systems and that the administration of some probiotics can improve mucosal barrier function, modulating the release of proinflammatory cytokines, in CFS/ME patients. This study represents a preliminary investigation to verifying the safety and efficacy of a certain combination of probiotics in CFS/ME patients. The results suggest that probiotics can modify the well-being status as well as inflammatory and oxidative indexes in CFS/ME patients. No adverse effects were observed except for one patient, which displayed a flare-up of symptoms, although all inflammatory parameters (i.e., cytokines, fecal calprotectin, ESR, and immunoglobulins) were reduced after probiotic intake. The reactivation of fatigue symptoms in this patient, whose clinical history reported the onset of CFS/ME following mononucleosis, could be related to an abnormal stimulation of the immune system as suggested by a recent study describing an exaggerated immune activation associated with chronic fatigue.

Isolation and characterization of high exopolysaccharide-producing Weissella confusa VP30 from young children's feces

Background

Lactic acid bacteria (LAB) are known to have a significant ability to colonize the human intestinal tract and adhere to the surface of intestinal epithelial cells. Among the various lactic acid bacteria, exopolysaccharide (EPS) producing strains are known to provide a variety of health benefits for their hosts (e.g. anti-inflammatory, antioxidant, antitumor and stress tolerant effects). Recently, EPSs and EPS-producing lactic acid cultures have gained interest within the food industry and are playing important roles as biothickeners and texturizing agents due to their hydrocolloidal nature. In this study, 156 lactic acid bacterial strains isolated from fecal samples of healthy young children were screened and evaluated for active EPS-production capability.

Results

Among the various human origin lactic acid flora isolated, Weissella confusa VP30 showed the highest EPS productivity and its EPS producing properties were characterized under various cultural conditions in this research. To document the safety of W. confusa VP30, antibiotic resistance, hemolytic, and ammonia production properties were evaluated in addition. No significant negative results were observed. The maximum EPS production by W. confusa VP30 was 59.99 ± 0.91 g/l after 48 h of cultivation in media containing 10% sucrose, far exceeding EPS production by other bacterial strains reported elsewhere. Based on gel permeation chromatography (GPC), the molecular weight of EPS produced by W. confusa VP30 was 3.8 × 10⁶ Da. Structural analysis of the released EPS fraction by ¹³C and ¹H nuclear magnetic resonance (NMR) spectroscopy revealed that W. confusa VP30 can produce dextran with glucose units linked with 96.5% α (1 → 6) glycosidic bonds and 3.5% α (1 → 3) branches.

Conclusion

The high EPS production capability and safety of W. confusa VP30 justify food industry consideration of this cell strain for further evaluation and potential industrial use.

Safety Evaluation of Oral Care Probiotics Weissella cibaria CMU and CMS1 by Phenotypic |and Genotypic Analysis

Weissella cibaria CMU and CMS1 are known to exert beneficial effects on the oral cavity but have not yet been determined to be generally recognized as safe (GRAS), although they are used as commercial strains in Korea. We aimed to verify the safety of W. cibaria CMU and CMS1 strains through phenotypic and genotypic analyses. Their safety was evaluated by a minimum inhibitory concentration assay for 14 antibiotics, DNA analysis for 28 antibiotic resistance genes (ARGs) and one conjugative element, antibiotic resistance gene transferability, virulence gene analysis, hemolysis, mucin degradation, toxic metabolite production, and platelet aggregation reaction. W. cibaria CMU showed higher kanamycin resistance than the European Food Safety Authority (EFSA) cut-off, but this resistance was not transferred to the recipient strain. W. cibaria CMU and CMS1 lacked ARGs in chromosomes and plasmids, and genetic analysis confirmed that antibiotic resistance of kanamycin was an intrinsic characteristic of W. cibaria. Additionally, these strains did not harbor virulence genes associated with pathogenic bacteria and lacked toxic metabolite production, β-hemolysis, mucin degradation, bile salt deconjugation, β-glucuronidase, nitroreductase activity, gelatin liquefaction, phenylalanine degradation, and platelet aggregation. Our findings demonstrate that W. cibaria CMU and CMS1 can achieve the GRAS status in future.

Bifidogenic properties of cell-free extracts derived from probiotic strains of Bifidobacterium bifidum and Lactobacillus reuteri

Comprehensive study of the biological activity of structural components and metabolites of “beneficial” microorganisms opens the prospects of efficient and rational use of their biotechnological potential in the correction of microecological and related disorders. The study tested proliferative activity and biofilm formation by Bifidobacterium bifidum probiotic strain under the influence of cell-free extracts containing structural components and metabolites of the probiotic strains of B. bifidum and Lactobacillus reuteri. Cell-free extracts were obtained by disintegrating suspensions of probiotic cells by cyclic freezing-thawing, cultivating probiotic microorganisms in their own disintegrates and subsequent filtration of the obtained disintegrates and cultures. The proliferative activity and biofilm formation of the probiotic test culture were studied by spectrophotometric microtiter plate method with 10%vol, 30%vol and 50%vol content of cell-free extracts in the cultivation medium. All investigated extracts showed a significant concentration-dependent stimulatory effect on the proliferative activity of B. bifidum. According to the degree of stimulatory effect on the B. bifidum proliferation, cell-free extracts arranged in ascending order: MLG (filtrate of L. reuteri culture, grown in L. reuteri disintegrate supplemented with 0.8 M glycerol and 0.4 M glucose) < MB (filtrate of В. bifidum culture, grown in В. bifidum disintegrate) < B (filtrate of В. bifidum disintegrate) < ML (filtrate of L. reuteri culture, grown in L. reuteri disintegrate) < L (filtrate of L. reuteri disintegrate). With the same content in the culture medium, filtrates of disintegrates had a more pronounced stimulatory effect than filtrates of cultures grown in their own disintegrates. Cell-free extracts from L. reuteri (L and ML) exerted a more pronounced stimulatory effect than cell-free extracts from B. bifidum. Not all studied cell-free extracts stimulated the biofilm formation by B. bifidum. The effect of cell-free extracts on this process depended on their type and concentration. Extract L had a predominantly inhibitory effect on biofilm formation by B. bifidum. The most pronounced stimulatory effect on biofilm formation by B. bifidum came from extract MLG. ML, B and MB extracts stimulated this process approximately equally. The detection of significant bifidogenic effect of the studied cell-free extracts may contribute to their pharmaceutical applications. Cell-free extracts can be used as metabiotics or prebiotics for increasing the survival of the injected probiotic, facilitating its inoculation in the gastrointestinal tract when used together. The obtained data encourage further careful study of the biochemical composition of cell-free extracts and efforts to clarify the mechanism of their action.

Improvement of electroporation-mediated transformation efficiency for a Bifidobacterium strain to a reproducibly high level

Bifidobacteria are representative probiotics which are defined as live microorganisms that confer a health benefit on the host. Because of their safety and healthfulness when applied to humans, bifidobacteria are suitable as genetically engineered bacteria for applications to benefit human physiology and pathology. However, molecular biological studies of bifidobacteria have been limited due to insufficient genetic tools including effective transformation methods. The aim of this study is to improve the electroporation-mediated transformation efficiency of bifidobacteria to a reproducibly high level. The crucial factors that determine electroporation efficiency are the restriction-modification system, together with the cell wall and cell membrane structure of the bacteria. We optimized the bifidobacterial electroporation conditions by focusing on these factors as well as the amount of plasmid DNA used, the electrical parameters and the bacterial growth phase. As a result, the electroporation efficiency of B. bifidum BGN4 drastically and consistently increased from 10³ to 10⁵ CFU / μg DNA. The most significant factor for increasing the electroporation efficiency was the cell wall weakening mediated by NaCl, which improved the electroporation frequency by 20 times. Because the optimized electrotransformation conditions reported here should be widely applicable to other Bifidobacterium species, these could promote the extensive genetic manipulation of the various Bifidobacterium species in future studies.

Production of Selenomethionine-Enriched Bifidobacterium bifidum BGN4 via Sodium Selenite Biocatalysis

Selenium is a trace element essential for human health that has received considerable attention due to its nutritional value. Selenium’s bioactivity and toxicity are closely related to its chemical form, and several studies have suggested that the organic form of selenium (i.e., selenomethionine) is more bioavailable and less toxic than its inorganic form (i.e., sodium selenite). Probiotics, especially Bifidobacteriium and Lactobacillus spp., have received increasing attention in recent years, due to their intestinal microbial balancing effects and nutraceutical benefits. Recently, the bioconversion (a.k.a biotransformation) of various bioactive molecules (e.g., minerals, primary and secondary metabolites) using probiotics has been investigated to improve substrate biofunctional properties. However, there have been few reports of inorganic selenium conversion into its organic form using Bifidobacterium and Lactobacillus spp. Here we report that the biosynthesis of organic selenium was accomplished using the whole cell bioconversion of sodium selenite under controlled Bifidobacterium bifidum BGN4 culture conditions. The total amount of organic and inorganic selenium was quantified using an inductively coupled plasma-atomic emission spectrometer (ICP-AES). The selenium species were separated via anion-exchange chromatography and analyzed with inductively coupled plasma-mass spectrometry (ICP-MS). Our findings indicated that the maximum level of organic selenium was 207.5 µg/g in selenium-enriched B. bifidum BGN4. Selenomethionine was the main organic selenium in selenium-enriched B. bifidum BGN4 (169.6 µg/g). Considering that B. bifidum BGN4 is a commercial probiotic strain used in the functional food industry with clinically proven beneficial effects, selenium-enriched B. bifidum BGN4 has the potential to provide dual healthy functions as a daily supplement of selenium and regulator of intestinal bacteria. This is the first report on the production of organic selenium using B. bifidum spp.