Bifidobacterium obtained from mother's milk and their infant stool; A comparative genotyping and antibacterial analysis

The preventive effects of native probiotic and postbiotic on inflammation and oxidative stress in DSS-induced colitis with normal diet: Which of these agents may offer greater advantages?

Background

Maintaining a well-rounded and healthy diet is essential to promote the well-being and optimal performance of the body, especially for those suffering from Inflammatory Bowel Disease (IBD). The objective of this study is to examine whether probiotics and postbiotics can modulate oxidative stress and inflammation, and to evaluate the properties of these compounds.

Methods

A total of eighty eight strains of Lactobacillus and Bifidobacterium were assessed for their antioxidant activities. C57BL/6 mice were allocated into four groups: normal diet (ND) + PBS, ND + DSS, ND + DSS + 10⁹ cfu/ml of probiotics, and ND + DSS + 10⁹ cfu/ml of postbiotics. Biochemical antioxidant assays, along with colitis indices, were evaluated. The ELISA assay was conducted to measure oxidant/antioxidant properties and cytokines. Additionally, the genes enrolled in NF-kB and Nrf2 signaling pathways was analyzed.

Results

In comparison to the groups exposed to DSS alone, mice that received our native agents in addition to DSS demonstrated an improvement in the negative effects induced by DSS on DAI and pathological scores, as well as on colon length and body weight. The levels of cytokines and antioxidant markers have also been normalized following the administration of our native agents, along with molecular markers. It should also be noted that our native postbiotic was able to develop more pronounced and significant anti-inflammatory and antioxidant effects in comparison to the probiotic strains.

Conclusion

In this study, our native postbiotic has demonstrated a more pronounced ability to exhibit antioxidant and anti-inflammatory effects. This finding is particularly important for individuals with impaired immune function, for whom the use of live bacteria could be risky. Therefore, the utilization of agents like probiotics and postbiotics, which come with minimal side effects in compared to chemical drugs, could be essential in managing symptoms in IBD patients.

The preventive and therapeutic role of Lactobacillus spp. in in vitro model of inflammation via affecting autophagy signaling pathway

BACKGROUND

Intestinal inflammation has various causes and leads to some inflammatory diseases, of which autophagy pathway dysfunction could be considered as one of them. Probiotics could have a positive effect on reducing inflammation by activating the autophagy pathway. To evaluate the precise effects of probiotics as preventive and therapeutic agents to control the symptoms of inflammatory diseases, we aimed to investigate the efficacy of Lactobacillus spp. in regulating the autophagy signaling pathway.

METHODS

A quantitative real-time polymerase chain reaction assay was used to analyze the expression of autophagy genes involved in the formation of phagophores, autophagosomes, and autolysosomes after exposing the HT-29 cell line to sonicated pathogens and adding Lactobacillus spp. before, after, and simultaneously with inflammation. A cytokine assay was also accomplished to evaluate the interleukin (IL)-6 and IL-1β level following the probiotic treatment.

RESULTS

Lactobacillus spp. generally increased autophagy gene expression and consumption of Lactobacillus spp. before, simultaneously, and after inflammation, ultimately leading to activate autophagy pathways. The proinflammatory cytokines including IL-6 and IL-1β decreased after probiotic treatment.

CONCLUSIONS

Our native probiotic Lactobacillus spp. showed beneficial effects on HT-29 cells by increasing autophagy gene expression and decreasing the proinflammatory cytokines production in all treatments. Therefore, this novel probiotic cocktail Lactobacillus spp. can prevent and treat inflammation-related diseases.

The effect of novel paraprobiotic cocktail on dextran sodium sulfate induced acute colitis control focusing on autophagy signaling pathway

PURPOSE

Paraprobiotics are a non-viable form of probiotics that are reported to provide significant health benefits. Nevertheless, little is known about the beneficial effects of paraprobiotics on inflammatory bowel disease. Although probiotics show potential as therapeutic agents for a range of diseases, including inflammatory bowel disease (IBD), there are certain risks associated with their use. These risks include toxin production, hemolytic potential, antibiotic resistance, and the need to analyze metabolic activities. Hence Using paraprobiotic with the lower aforementioned risk would therefore be the preferable option. Here, we conducted an in vivo study to evaluate the preventive effect of our native paraprobiotic cocktail against dextran sulfate sodium (DSS)-induced murine colitis by affecting the autophagy signaling pathway.

METHODS

Four-week-old male C57Bl/6 mice were randomly divided into three groups after a two-week acclimation period with normal standard laboratory food diet. Mice were administered PBS (PBS group as control), PBS along with DSS (DSS group, as a control), and a cocktail of paraprobiotics along with DSS (Para group). The severity of colitis, length and histopathology of the colon were evaluated. In addition, the expression of autophagy was assessed using real-time PCR.

RESULTS

The results showed that administration of the paraprobiotic cocktail to DSS-treated mice inhibited the severity of colitis symptoms, as evidenced by the inhibition of weight loss and DAI, as well as histopathological scores in the study colon, as well as shortening of colon length caused by DSS. In contrast to the DSS group, the cocktail was able to modulate inflammation through upregulation of autophagy-related genes (becline 1, atg5, atg7, atg12, and atg13).

CONCLUSION

Although there are some limitations in our investigation, such as the dosage and duration of treatments, our native paraprobiotic blend effectively prevented the advancement of colitis. This suggests that it plays a vital role in regulating inflammation and preventing colitis by promoting the autophagy mechanism in cases where the consumption of probiotics may have negative consequences.

Characterization of Antimicrobial Activities of Bifidobacterium lactis BB-12 and Their Inhibitory Effect Against Some Foodborne Pathogens

Bifidobacterium animalis subsp. lactis BB-12, a probiotic, has shown potential to promote health benefits and control pathogens. This study aimed to investigate the effectiveness of BB-12 and its cell-free supernatant (CFS) in inhibiting the growth of Listeria monocytogenes and Salmonella enterica serovar Typhimurium. To assess the antimicrobial activity of BB-12, agar well diffusion, disk diffusion, and minimum inhibitory concentration (MIC) tests were conducted. The bicinchoninic acid (BCA) assay was performed to measure the protein concentration in CFS. The study's results indicated that the BB-12 strain inhibited the pathogens' growth. The disk diffusion test using BB-12 showed inhibitory results ranging from 11 to 14 mm for both bacteria. The agar well diffusion test reported the zone of inhibition ranging from 11.6 to 16 mm for both bacteria. The MIC test was conducted as a confirmatory test, which demonstrated the highest inhibitory zone using 2 McFarland (6 × 108 CFU/mL) concentrations of probiotics on L. monocytogenes (44.98%) and S. Typhimurium (66.41%). The disk diffusion test revealed that the probiotic CFS had a significant inhibitory impact on S. Typhimurium with a 16.6 mm zone of inhibition. The BCA test findings indicated that the 24- and 48-h CFSs exhibited inhibitory properties against infections. Notably, the 24-h CFS, including a protein level of 78.47 μg/mL, demonstrated a more pronounced inhibitory impact on both pathogens. The findings highlight that utilizing the BB-12 strain and its CFS can serve as a viable approach to battle infections, enhancing food safety and public health.

Investigating the antimicrobial and anti-inflammatory effects of Lactobacillus and Bifidobacterium spp. on cariogenic and periodontitis pathogens

Background

The use of probiotics is emerging as an innovative approach to managing oral health issues and mediating the immune system. The current study assessed the in vitro impacts of non-orally isolated probiotics on periodontitis and tooth decay pathogens.

Methods

Briefly, the persistence of probiotics in exposure to oral cavity enzymes, hydrogen peroxide, and saliva samples was examined. It was also investigated the biofilm formation and aggregation ability of probiotics, the adherence of probiotics in human gingival fibroblast cell (HGFC) lines and molar teeth samples, and the potential of probiotics to co-aggregate with oral pathogens. Additionally, the current study evaluated the effects of live probiotics on virulence gene expression, biofilm production of main oral pathogens, and changes in inflammation markers.

Results

The probiotics remained alive when exposed to enzymes in the oral cavity, hydrogen peroxide, and saliva at baseline, 1, 3, and 5 h after incubation at 37°C (p-value <0.05). Probiotics demonstrated to produce biofilm and aggregation, as well as adherence to HGFCs and maxillary molars (p-value >0.05). They showed significant co-aggregation with oral pathogens, which were recorded as 65.57% for B. bifidum 1001 with S. mutans, 50.06% for B. bifidum 1005 with P. gingivalis, 35.6% for L. plantarum 156 with F. nucleatum, and 18.7% for B. longum 1044 with A. actinomycetemcomitans after 8 h of incubation. A balance between pro-inflammatory and anti-inflammatory cytokines, along with inhibition of biofilm formation and changes in virulence gene transcripts, were observed. However, most of these changes were not statistically significant (p-value >0.05).

Conclusion

This study demonstrated the direct link between adhesiveness, aggregation, and biofilm formation with probiotic antibacterial activity. In addition to the careful selection of suitable probiotic strains, the concentration and origin of probiotic isolates should be considered.

The comparative anti-oxidant and anti-inflammatory efficacy of postbiotics and probiotics through Nrf-2 and NF-kB pathways in DSS-induced colitis model

IBD is a disorder which could be caused by oxidative stress. This investigation aims to determine if probiotics and postbiotics can control oxidative stress and inflammation and compare the effectiveness of these two probiotic and postbiotic mixtures of substances. 88 strains of Lactobacillus and Bifidobacterium were tested for antioxidant activity. Male wild-type C57BL/6 mice were divided into four experimental groups, namely high fat diet (HFD) + PBS, HFD + DSS, HFD + DSS + 109 cfu/ml of probiotics, and HFD + DSS + 109 cfu/ml of postbiotics. The phenotypical indices and pathological scores were assessed. The expression of genes related to NF-kB and Nrf2 signaling pathways and enzymes associated with oxidant/anti-oxidant activities, and proinflammatory/inflammatory cytokines were assessed. In contrast to the groups exposed to DSS, mice treated with probiotics mixture and postbiotics mixture alongside DSS displayed alleviation of DSS-induced adverse effects on phenotypical characteristics, as well as molecular indices such as the Nrf2 and NF-kB related genes, with a greater emphasis on the postbiotics component. In accordance with the findings of the present investigation, it can be inferred that even in using a high-fat dietary regimen as an inducer of oxidative stress, the emergence of inflammation can be effectively addressed through the utilization of probiotics and, more specifically, postbiotics.

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.

Isolation, identification, and in vitro probiotic characterization of forty novel Bifidobacterium strains from neonatal feces in Erzurum province, Türkiye

BACKGROUND

Neonatal feces are one of the most important sources for probiotic isolation. The purpose of this study was the isolation and identification of Bifidobacterium spp. from neonatal feces and the evaluation of in vitro probiotic properties of strains including safety tests.

RESULTS

A total of 40 isolates were obtained from 14 healthy newborns' feces in Erzurum province, Türkiye. By their rep-PCR patterns and 16S rRNA gene sequences, isolates were identified as 26 Bifidobacterium breve and 14 Bifidobacterium longum. Fifteen of the isolates tolerated bile salts and showed high resistance to simulated gastric juice. Isolates exhibited varying rates of auto-aggregation and hydrophobicity. In addition, most of the isolates displayed antibacterial activity against Escherichia coli O157:H7, Staphylococcus aureus ATCC 29213, Salmonella Typhimurium RSHMB 95091, and Pseudomonas aeruginosa ATCC 9027. However, only one strain showed bile salt hydrolase activity and two strains showed the ability to produce H2O2. Bifidobacterium strains were generally sensitive to the tested antibiotics and lacked kanamycin, gentamicin, and streptomycin resistance genes, and hemolytic and DNAse activities. On the other hand, it was determined that five strains had various virulence genes including gelE, esp, efaAfs, hyl, and ace.

CONCLUSION

Results of the present study suggested that B. longum BH28, B. breve BH4 and B. breve BH5 strains have the potential as probiotic candidates for further studies. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Investigating the crucial role of selected Bifidobacterium probiotic strains in preventing or reducing inflammation by affecting the autophagy pathway

Several studies have shown that probiotics can prevent and reduce inflammation in inflammation-related diseases. However, few studies have focused on the interaction between host and probiotics in modulating the immune system through autophagy. Therefore, we aimed to investigate the preventive and/or therapeutic effects of native potential probiotic breast milk-isolated Bifidobacterium spp. (i.e. B. bifidum, B. longum, and B. infantis) on the inflammatory cascade by affecting autophagy gene expression 24 and 48 h after treatment. Autophagy genes involved in different stages of the autophagy process were selected by quantitative polymerase chain reaction (qPCR). Gene expression investigation was accomplished by exposing the human colorectal adenocarcinoma cell line (HT-29) to sonicated pathogens (1.5 × 108 bacterial CFU ml-1) and adding Bifidobacterium spp. (MOI10) before, after, and simultaneously with induction of inflammation. An equal volume of RPMI medium was used as a control. Generally, our native potential probiotic Bifidobacterium spp. can increase the autophagy gene expression in comparison with pathogen. Moreover, an increase in gene expression was observed with our probiotic strains' consumption in all stages of autophagy. Totally, our selected Bifidobacterium spp. can increase autophagy gene expression before, simultaneously, and after the inflammation induction, so they can prevent and reduce inflammation in an in vitro model of inflammation.

The Anti-Inflammatory Effect of a Probiotic Cocktail in Human Feces Induced-Mouse Model

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract due to altered interaction between the immune system and the gut microbiota. The aim of this study was to investigate the role of a probiotic cocktail in modulating immune dysregulation induced in mice. Mice were divided into 5 groups (n = 5/group), and inflammation was induced in two separate groups by fecal microbiota transplantation (FMT) from the stool of human with IBD and dextran sulfate sodium (DSS). In the other two groups, the cocktail of Lactobacillus spp. and Bifidobacterium spp. (108CFU/kg/day) was administered daily for a total of 28days in addition to inducing inflammation. A group as a contcxsrol group received only water and food. The alteration of the selected genera of gut microbiota and the expression of some genes involved in the regulation of the inflammatory response were studied in the probiotic-treated and untreated groups by quantitative real-time PCR. The selected genera of gut microbiota of the FMT and DSS groups showed similar patterns on day 28 after each treatment. In the probiotic-treated groups, the population of the selected genera of gut microbiota normalized and the abundance of Firmicutes and Actinobacteria increased compared to the DSS and FMT groups. The expression of genes related to immune response and tight junctions was positively affected by the probiotic. Changes in the gut microbiota could influence the inflammatory status in the gut, and probiotics as a preventive or complementary treatment could improve the well-being of patients with inflammatory bowel disease symptoms.

Investigation of the anti-inflammatory effects of native potential probiotics as supplementary therapeutic agents in an in-vitro model of inflammation

BACKGROUND

IBD is considered an inflammatory disease with abnormal and exaggerated immune responses. To control the symptoms, different theraputic agents could be used, however, utilizing the agents with the least side effects could be important. Probiotics as beneficial microorganisms are one of the complementory theraputic agents that could be used to modulate inflammatory signaling pathways. In the current study, we aimed to identify the precise molecular effects of potential probiotics on signaling pathways involved in the development of inflammation.

METHODS

A quantitative real-time polymerase chain reaction (qPCR) assay was used to analyze the expression of JAK /STAT (JAK1, JAK2, JAK3, TYK2, STAT1, STAT2, STAT3, STAT4, STAT5 and STAT6) and inflammatory genes (NEMO, TIRAP, IRAK, and RIP) after the HT -29 cell line treatment with the sonicated pathogens and potential probiotics. A cytokine assay was also used to evaluate IL -6 and IL -1β production after potential probiotic treatment.

RESULTS

The potential probiotic cocktail downregulated the JAK genes and TIRAP, IRAK4, NEMO, and RIP genes in the NF-kB pathway compared with cells that were treated with sonicated gram negative pathogens. The expression of STAT genes was different after potential probiotic treatment. The production of IL -6 and IL -1β decreased after potential probiotic treatment.

CONCLUSIONS

Considering the importance of controlling the symptoms of IBD to improve the life quality of the patients, using probiotic could be crucial. In the current study the studied native potential probiotic cocktails showed anti-inflammatory effects via modulation of JAK /STAT and NF-kB signaling pathways. This observation suggests that our native potential probiotics consumption could be useful in reducing intestinal inflammation.

Ameliorating inflammation in an in vitro model by screening the anti-inflammatory and immunomodulatory roles of putative probiotics in inflammatory bowel disease

IBD is considered a relapsing disease with relapsing phases. Probiotics are beneficial microorganisms that modulate inflammatory signaling pathways. Our aim was to identify the precise molecular effects of probiotics on inflammatory signaling pathways during the presence of inflammation. Evaluation of the expression of JAK/STAT and inflammatory genes after treatment of the HT -29 cell line with the sonicated pathogens and probiotics, simultaneously was performed by quantitative real-time polymerase chain reaction (qPCR) assay. The production of IL-6 and IL-1β after administration of probiotics was conducted by means of cytokine assay. The probiotic cocktail resulted in the downregulation of TIRAP, IRAK4, NEMO, and RIP genes in the NF-кB pathway compared with Sonicat-treated cells. The expression of JAK/STAT genes was various after probiotic treatment. The application of probiotics has been observed to result in a notable decrease in the production of IL-6 and IL-1β. The investigated probiotic cocktail, especially Bifidobacterium spp. showed anti-inflammatory effects on HT -29 cells via modulation of JAK/STAT and NF-кB signaling pathways. The use of probiotics with the least side effects could be considered a suitable treatment for patients with inflammatory bowel disease, even at the beginning of inflammation.

Prophylactic vs. Therapeutic Effect of Probiotics on the Inflammation Mediated by the NF-κB Pathway in Inflammatory Bowel Conditions

Probiotic supplements consumed adequately at the proper time can affect health by modulating inflammatory pathways in gastrointestinal epithelial cells and modifying the resultant inflammatory response. The current study applied in vitro models to investigate the effectiveness of probiotics in modulating inflammatory pathways and altering inflammatory gene expression in gastrointestinal epithelial cells, with the ultimate goal of promoting probiotic consumption as a therapeutic and preventive measure for chronic inflammatory bowel conditions. HT-29 cells were treated with Gram-negative bacteria to evaluate the changes in pathways related to inflammation activities before and after treatment with a Lactobacillus spp. cocktail (L. plantarum, L. rhamnosus, L. brevis, and L. ruteri) and a Bifidobacterium spp. cocktail (B. bifidum, B. langum, and B. breve) using the real-time PCR method and ELISA for IL-1β and IL-6 as pro-inflammatory cytokines. The results showed that the expression of NF-κB signaling pathway genes and IL-1β and IL-6 cytokines increased after exposure to Gram-negative components. In contrast, all probiotic combinations significantly decreased the expression of genes and the secretion of cytokines. However, this decrease was significantly smaller in cells that underwent probiotic treatment after inflammation induction. In addition, cocktails containing combined Lactobacillus and Bifidobacterium demonstrated robust anti-inflammatory activity relative to solo cocktails. Our observations confirm that probiotic consumption could positively impact inflammatory conditions and alleviate inflammatory symptoms; they can be particularly effective as a preventive measure. Our study provides preliminary evidence to support the lifetime consumption of probiotics.

The Role of Combining Probiotics in Preventing and Controlling Inflammation: A Focus on the Anti-Inflammatory and Immunomodulatory Effects of Probiotics in an In Vitro Model of IBD

OBJECTIVE

IBD is an inflammatory disease with abnormalities such as dysbiosis and abnormal immune system activity. Probiotics, as live beneficial microorganisms, play a role in maintaining health through various mechanisms, including the modulation of the immune system and the control of inflammation. Here, we aimed to investigate the efficacy of a probiotic mixture of Lactobacillus spp. and Bifidobacterium spp. in modulating JAK/STAT and NF-kB inflammatory signaling pathways.

METHOD

A quantitative real-time polymerase chain reaction (qPCR) assay was conducted to analyze the expression of JAK/STAT and inflammatory genes after treatment with the probiotic mixture before, after, and simultaneously with the sonicated pathogen in the HT-29 cell line. The production of IL-6 and IL-1β after probiotic treatment was investigated via cytokine assay.

RESULTS

Treatment with probiotics resulted in downregulation of TIRAP, IRAK4, NEMO, and RIP genes in the NF-kB pathway and JAK/STAT genes compared with sonicat-treated cells as inflammation inducers. The production of IL-6 and IL-1 decreased after probiotic treatment.

CONCLUSIONS

The probiotic mixture of Lactobacillus spp. and Bifidobacterium spp. showed anti-inflammatory effects by modulating JAK/STAT and NF-kB signaling pathways. The use of probiotics could be considered as an appropriate complementary treatment for patients with inflammatory bowel disease.

The potential role of Bifidobacterium spp. as a preventive and therapeutic agent in controlling inflammation via affecting inflammatory signalling pathways

Inflammatory bowel disease (IBD) is a chronic inflammatory disease with relapses and periods of remission. Forasmuch as, dysregulation of the immune system is one of the triggers of IBD, taking probiotics as one of the immunomodulators in the gut, could help to control inflammation and IBD via influencing signalling pathways. Here, we aimed to investigate the efficacy of five selected Bifidobacterium strains in modulating JAK/STAT and NF-kB inflammatory signalling pathways via using the in vitro assay. A quantitative real-time polymerase chain reaction assay was used to analyse the expression of JAK/STAT and inflammatory genes followed by potential probiotic treatments before, after and simultaneously with the inflammation induction (sonicated pathogen). The production of IL-6 and IL-1β after probiotic treatment was evaluated. Probiotic treatment resulted in the downregulation of TIRAP, IRAK4, NEMO and RIP genes in the NF-kB pathway, as well as JAK genes compared to sonicate-treated cells. The expression of STAT genes was different after our selected Bifidobacterium strains treatment. The production of IL-6 and IL-1β decreased after probiotic treatment. These strains of Bifidobacterium spp. showed anti-inflammatory effects on HT-29 cells via modulation of JAK/STAT and NF-kB signalling pathways. The use of Bifidobacterium spp. could be considered as a suitable preventive and complementary treatment for patients with inflammatory bowel disease.

The impact of Lactobacillus and Bifidobacterium probiotic cocktail on modulation of gene expression of gap junctions dysregulated by intestinal pathogens

Probiotics are special bacterial strains with strain specific impacts. They can affect health condition in intestine by producing organic acid, competing with pathogens and maintaining cells homeostasis. Regarding to importance of cell junctions in cells transportation and the influence of pathogens in their functions which lead to inflammation, the impact of probiotic strains comprised of Lactobacillus and Bifidobacterium strains on two important members of gap junctions (Cx26 and Cx43) were assayed. The expressions of cell junction genes in contact with probiotic cocktail along with pathogenic components of enterotoxigenic Escherichia coli and Salmonella typhimurium on HT-29 cell line in different treatment orders were evaluated. Results analysis demonstrated downregulation of cx26 and cx43 along with pathogenic components while, probiotic cocktail could modulate their expression by upregulation. We concluded that Lactobacillus and Bifidobacterium strains were efficient probiotics, when they were used as one cocktail, impacted grater amount on the expression of cell junctions and this might lead to modulate homeostasis and reveal inflammation symptoms in intestine.

In vitro evaluation of probiotic properties and antioxidant activities of Bifidobacterium strains from infant feces in the Uyghur population of northwestern China

Purpose

Bifidobacterium is an important probiotic used in food and medicine production. The probiotic properties of bifidobacteria are strain specific, so it is necessary to evaluate the probiotic properties of bifidobacteria isolated from specific populations, especially when developing products suitable for specific populations. The objective of this study was to evaluate the probiotic potential and safety of bifidobacteria isolated from healthy Uyghur infants from northwestern China.

Methods

In this study, antimicrobial activity, antibiotic sensitivity, hemolytic, acid and bile tolerance, hydrophobicity, co-aggregation, auto-aggregation, and antioxidant activity were evaluated.

Results

Based on antagonistic activity spectrum against seven intestinal pathogenic bacteria, 14 excellent strains were initially selected. Among 14 strains, four bifidobacteria strains (BF17-4, BF52-1, BF87-3, and BF88-5) were superior to strain Lactobacillus rhamnosus GG in cell surface hydrophobicity and auto-aggregation percentages and close to strain GG in co-aggregation with Escherichia coli EPEC O127: K63 (CICC 10411). The antioxidant activities of each of the 14 bifidobacteria strains varied with the cell components. Most of the strains were sensitive to all the antimicrobials tested, except kanamycin and amikacin.

Conclusion

BF17-4 and BF52-1 are good candidates for further in vivo studies and further used in functional foods.

The effects of the probiotic cocktail on modulation of the NF-kB and JAK/STAT signaling pathways involved in the inflammatory response in bowel disease model

Background

Probiotics positively affect inflammatory responses, in part, through Janus kinase/signal transduction and activator of transcription (JAK/STAT) and inflammatory signaling pathways. To evaluate the precise effects of probiotics as protective treatment, we aimed to investigate the effectiveness of Lactobacillus spp., Bifidobacterium spp., and a mixture of these probiotics in modulating the JAK/STAT and inflammatory signaling pathways.

Methods

A quantitative real-time polymerase chain reaction (qPCR) assay was used to analyze the expression of JAK/STAT and inflammatory genes (TIRAP, IRAK4, NEMO, and RIP) following HT-29 cell line treatment with sonicated pathogens Lactobacillus spp., Bifidobacterium spp., and a mixed cocktail. A cytokine assay was also used to evaluate the IL-6 and IL-1β production following the probiotic treatment.

Results

The probiotic cocktail downregulated the JAK genes and TIRAP, IRAK4, NEMO, and RIP genes in the NF-kB pathway compared to sonicate pathogen treatment cells. The expression of STAT genes was variable following probiotic treatment. The IL-6 and IL-1β production decreased after probiotic treatment.

Conclusions

Our probiotic cocktail showed anti-inflammatory effects on HT-29 cells by modulating JAK/STAT and NF-kB pathways. Therefore, Lactobacillus spp. and Bifidobacterium spp. probiotics as nutritional supplements may reduce inflammation-associated diseases such as inflammatory bowel disease (IBD).

Identification, Characterization, and Antioxidant Potential of Bifidobacterium longum subsp. longum Strains Isolated From Feces of Healthy Infants

Increasing evidence has indicated that oxidative stress is associated with the health of infants. Bifidobacterium, especially B. longum subsp. longum strains, are abundant in the gut microbiota of infants, which may have the potential to ameliorate oxidative damage. Thus, this study aimed to isolate and screen B. longum subsp. longum strains with probiotic characters and antioxidant properties as infants’ dietary supplements. In this study, 24 B. longum subsp. longum strains were isolated from 15 healthy infants identified via 16S rRNA and heat shock protein 60 (hsp60) sequences. B. longum subsp. longum B13, F2, K4, K5, K10, K13, and K15 strains were selected based on high values obtained from autoaggregation, hydrophobicity, and adhesion assays to HT-29 cells. Among these seven strains, B. longum subsp. longum F2, K5, K10, and K15 were selected according to the high tolerance of gastrointestinal tract conditions compared to Bifidobacterium animalis subsp. lactis BB-12. Among these four strains, B. longum subsp. longum K5 was susceptible to common antibiotics and showed the highest intestinal epithelial cell proliferation of CCD 841 CoN. Additionally, B. longum subsp. longum K5 showed a strong antioxidant capacity, and its supernatant exhibited better activity of reducing power, hydroxyl radical scavenging, and DPPH radical scavenging than that of the intact cells with cell-free extracts. The findings indicated that B. longum subsp. longum K5 could be used as a probiotic candidate in infant nutrition.

The effect of improved formulation of chitosan-alginate microcapsules of Bifidobacteria on serum lipid profiles in mice

BACKGROUND

Probiotics have been associated with many beneficial effects in human digestive physiology. The aim of this study was to evaluate the effect of improved formulation of chitosan-alginate microcapsules of Bifidobacterium strains on serum triglycerides, cholesterol, HDL, and LDL in mice.

METHODS

Five approved probiotic strains of Bifidobacterium were tested for anti-proliferative effect and interleukin-8 induction on HT-29 cell lines. Bifidobacterium strains plus five approved Lactobacillus were encapsulated in chitosan-alginate microcapsules and tested for its survival in simulated gastrointestinal conditions. These microcapsules were administered to 4 groups of mice (including 1. Bif (Bifidobacterium strains), 2. Lac (Lactobacillus strains), 3. Bif-Lac (Bifidobacterium plus Lactobacillus strains) and 4. Control) for 8 days. At eighth day, the blood of mice were taken and serum levels of triglycerides, cholesterol, HDL, and LDL of them were determined.

RESULTS

All of the Bifidobacterium strains significantly (P < 0.001) reduced secretion of IL-8 in HT-29 cells as well as maximum antiproliferative effects (P < 0.001). In addition, all microcapsules showed impressive survival rate in bile (>%94.1) and gastrointestinal (>%78.28) conditions (P < 0.05). Only Bif-Lac group displayed significantly lower serum cholesterol and LDL levels than control group (P < 0.05). Besides, all groups indicate statistically significant weight loss of mice during the 8 days in comparison with the control group (P < 0.05).

CONCLUSION

The results of this study showed that the microencapsulated probiotics with alginate and chitosan had an effective mean of delivery of viable bacterial cells and non-pharmacological interventions use to reduce serum cholesterol and LDL levels in in-vivo condition.

Anti-cancer effects of Bifidobacterium species in colon cancer cells and a mouse model of carcinogenesis

INTRODUCTION

Probiotics are suggested to prevent colorectal cancer (CRC). This study aimed to investigate the anticancer properties of some potential probiotics in vitro and in vivo.

MATERIALS AND METHODS

Anticancer effects of the following potential probiotic groups were investigated in LS174T cancer cells compared to IEC-18 normal cells. 1. a single strain of Bifidobacterium. breve, 2. a single strain of Lactobacillus. reuteri, 3. a cocktail of 5 strains of Lactobacilli (LC), 4. a cocktail of 5 strains of Bifidobacteria (BC), 5. a cocktail of 10 strains from Lactobacillus and Bifidobacterium (L+B). Apoptosis rate, EGFR, HER-2 and PTGS-2 (COX-2 protein) expression levels were assessed as metrics of evaluating anticancer properties. Effect of BC, as the most effective group in vitro, was further assessed in mice models.

RESULTS

BC induced ~21% and only ~3% apoptosis among LS174T and IEC-18 cells respectively. BC decreased the expression of EGFR by 4.4 folds, HER-2 by 6.7 folds, and PTGS-2 by 20 folds among the LS174T cells. In all these cases, BC did not interfere significantly with the expression of the genes in IEC-18 cells. This cocktail has caused only 1.1 folds decrease, 1.8 folds increase and 1.7 folds decrease in EGFR, HER-2 and PTGS-2 expression, respectively. Western blot analysis confirmed these results in the protein level. BC significantly ameliorated the disease activity index, restored colon length, inhibited the increase in incidence and progress of tumors to higher stages and grades.

CONCLUSIONS

BC was the most efficient treatment in this study. It had considerable "protective" anti-cancer properties and concomitantly down regulated EGFR, HER-2 and PTGS-2 (COX-2), while having significant anti-CRC effects on CRC mice models. In general, this potential probiotic could be considered as a suitable nutritional supplement to treat and prevent CRC.

Breast Milk, a Source of Beneficial Microbes and Associated Benefits for Infant Health

Human breast milk is considered the optimum feeding regime for newborn infants due to its ability to provide complete nutrition and many bioactive health factors. Breast feeding is associated with improved infant health and immune development, less incidences of gastrointestinal disease and lower mortality rates than formula fed infants. As well as providing fundamental nutrients to the growing infant, breast milk is a source of commensal bacteria which further enhance infant health by preventing pathogen adhesion and promoting gut colonisation of beneficial microbes. While breast milk was initially considered a sterile fluid and microbes isolated were considered contaminants, it is now widely accepted that breast milk is home to its own unique microbiome. The origins of bacteria in breast milk have been subject to much debate, however, the possibility of an entero-mammary pathway allowing for transfer of microbes from maternal gut to the mammary gland is one potential pathway. Human milk derived strains can be regarded as potential probiotics; therefore, many studies have focused on isolating strains from milk for subsequent use in infant health and nutrition markets. This review aims to discuss mammary gland development in preparation for lactation as well as explore the microbial composition and origins of the human milk microbiota with a focus on probiotic development.

Characterization of bacteriocin production in Lactobacillus spp. isolated from mother's milk

The purpose of the present study was to isolate Lactobacillus bacteria from mother's milk and to assess their probiotic potential. Sixty breast milk samples were collected from the volunteered mothers aged from 19 to 35 and from rural areas of Lorestan and Markazi Provinces, Iran. At first, 970 bacill-shaped bacterial colonies were isolated from these samples and stored in proper condition. Two hundred isolates were randomly selected and investigated for their ability to tolerate acidic condition and to tolerate bile salt as well. Only 33 isolates could withstand the exposure to low pH and bile salt. The isolates were identified using PCR primer specific to Lactobacillus and it was demonstrated that eighteen of thirty-three isolates were belonged to the Lactobacillus. Among the isolates, 16 and 2 of them were Lactobacillus reuteri and L. gasseri, respectively. In addition, the antibiotic resistance of the isolates was determined using disc diffusion method and all of the isolates were shown to be sensitive to eight out of the twelve investigated antibiotics. Moreover, the antagonistic effect of the isolates was inspected on ten indicator pathogens. Interestingly, all of the pathogenic bacteria were inhibited by Lactobacillus isolates. In addition, to partially understand the nature of inhibition mechanism, well diffusion deployed for two randomly-selected indicator bacteria and the resulting halos of three isolates were statistically significant compared to other lactobacillus (p < 0.05). Subsequently, bacteriocin genes (plnS, Laf, gasA) were identified by PCR among the isolates. The results showed that only 2 isolates possessed the gasA gene which were in accordance with well diffusion test. Consequently, eighteen Lactobacillus isolated from breast milk samples which all of them were able to tolerate low pH and bile salt. Similarly, all of the Lactobacillus isolates were proved to inhibit the growth of pathogen strains and two of them possess a bacteriocin-related gene.

Impact of gut-associated bifidobacteria and their phages on health: two sides of the same coin?

Bifidobacteria are among the first microbial colonisers of the human infant gut post-partum. Their early appearance and dominance in the human infant gut and the reported health-promoting or probiotic status of several bifidobacterial strains has culminated in intensive research efforts that focus on their activities as part of the gut microbiota and the concomitant implications for human health. In this mini-review, we evaluate current knowledge on the genomics of this diverse bacterial genus, and on the genetic and functional adaptations that have underpinned the success of bifidobacteria in colonising the infant gut. The growing interest in functional genomics of bifidobacteria has also created interest in the interactions of bifidobacteria and their (bacterio)phages. While virulent phages of bifidobacteria have yet to be isolated, the incidence of integrated (pro)phages in bifidobacterial genomes are widely reported and this mini-review considers the role of these so-called bifidoprophages in modulating bifidobacterial populations in the human gastrointestinal tract and the implications for existing and future development of probiotic therapies.