Evaluation of the probiotic properties of new Lactobacillus and Bifidobacterium strains and their in vitro effect

Effects of dietary metabolizable energy level on hepatic lipid metabolism and cecal microbiota in aged laying hens

Lipid metabolic capacity, feed utilization, and the diversity of gut microbiota are reduced in the late laying stage for laying hens. This experiment aimed to investigate the effects of different levels of dietary metabolizable energy (ME) on hepatic lipid metabolism and cecal microbiota in late laying hens. The 216 Peking Pink laying hens (57-wk-old) were randomly assigned to experimental diets of 11.56 (HM = high ME), 11.14 (MM = medium ME), or 10.72 (LM = low ME) MJ of ME/kg, with each dietary treatment containing 6 replicates per group and 12 chickens per replicate. The HM group showed higher triglyceride (TG), total cholesterol (T-CHO), and low-density lipoprotein cholesterol (LDL-C) concentrations in the liver compared with the LM group; second, the HM group showed higher TG concentration and the LM group showed lower T-CHO concentration compared with MM group; finally, the HM group showed a lower hepatic lipase (HL) activity compared with the MM and LM groups (P < 0.05). There was a significant difference in the microbial community structure of the cecum between the HM and MM groups (P < 0.05). The decrease of dietary ME level resulted in a gradual decrease relative abundance of Proteobacteria. At the genus level, beneficial bacteria were significantly enriched in the LM group compared to the MM group, including Faecalibacterium, Lactobacillus, and Bifidobacterium, (linear discriminant analysis [LDA] >2, P <0.05). In addition, at the species level, Lactobacillus crispatus, Parabacteroides gordonii, Blautia caecimuris, and Lactobacillus johnsonii were significantly enriched in the LM group (LDA>2, P < 0.05). The HM group had a higher abundance of Sutterella spp. compared to the LM group (LDA>2, P <0.05). In conclusion, this research suggests that the reduction in dietary energy level did not adversely affect glycolipid metabolism or low dietary ME (10.72 MJ/kg). The findings can be helpful for maintaining intestinal homeostasis and increasing benefit for gut microbiota in late laying hens.

Who inhabits the built environment? A microbiological point of view on the principal bacteria colonizing our urban areas

Modern lifestyle greatly influences human well-being. Indeed, nowadays people are centered in the cities and this trend is growing with the ever-increasing population. The main habitat for modern humans is defined as the built environment (BE). The modulation of life quality in the BE is primarily mediated by a biodiversity of microbes. They derive from different sources, such as soil, water, air, pets, and humans. Humans are the main source and vector of bacterial diversity in the BE leaving a characteristic microbial fingerprint on the surfaces and spaces. This review, focusing on articles published from the early 2000s, delves into bacterial populations present in indoor and outdoor urban environments, exploring the characteristics of primary bacterial niches in the BE and their native habitats. It elucidates bacterial interconnections within this context and among themselves, shedding light on pathways for adaptation and survival across diverse environmental conditions. Given the limitations of culture-based methods, emphasis is placed on culture-independent approaches, particularly high-throughput techniques to elucidate the genetic and -omic features of BE bacteria. By elucidating these microbiota profiles, the review aims to contribute to understanding the implications for human health and the assessment of urban environmental quality in modern cities.

Positive modulation of a new reconstructed human gut microbiota by Maitake extract helpfully boosts the intestinal environment in vitro

The human gut is a complex environment where the microbiota and its metabolites play a crucial role in the maintenance of a healthy state. The aim of the present work is the reconstruction of a new in vitro minimal human gut microbiota resembling the microbe-microbe networking comprising the principal phyla (Bacillota, Bacteroidota, Pseudomonadota, and Actinomycetota), to comprehend the intestinal ecosystem complexity. In the reductionist model, we mimicked the administration of Maitake extract as prebiotic and a probiotic formulation (three strains belonging to Lactobacillus and Bifidobacterium genera), evaluating the modulation of strain levels, the release of beneficial metabolites, and their health-promoting effects on human cell lines of the intestinal environment. The administration of Maitake and the selected probiotic strains generated a positive modulation of the in vitro bacterial community by qPCR analyses, evidencing the prominence of beneficial strains (Lactiplantibacillus plantarum and Bifidobacterium animalis subsp. lactis) after 48 hours. The bacterial community growths were associated with the production of metabolites over time through GC-MSD analyses such as lactate, butyrate, and propionate. Their effects on the host were evaluated on cell lines of the intestinal epithelium and the immune system, evidencing positive antioxidant (upregulation of SOD1 and NQO1 genes in HT-29 cell line) and anti-inflammatory effects (production of IL-10 from all the PBMCs). Therefore, the results highlighted a positive modulation induced by the synergic activities of probiotics and Maitake, inducing a tolerogenic microenvironment.

The consequences of fermentation metabolism on the qualitative qualities and biological activity of fermented fruit and vegetable juices

Fermentation of fruit and vegetable juices with probiotics is a novel nutritional approach with potential health benefits. Lactic acid fermentation-based biotransformation results in changes in the profile and nature of bioactive compounds and improves the organoleptic properties, shelf life and bioavailability of vitamins and minerals in the fermented juices. This process has been shown to enrich the phenolic profile and bioactivity components of the juices, resulting in a new type of functional food with improved health benefits. Fruits and vegetables are the ideal substrate for microbial growth, and fruit and vegetable juice will produce rich nutrients and a variety of functional activities after fermentation, so that the high-quality utilization of fruits and vegetables is realized, and the future fermented fruit and vegetable juice products have a wide application market. This paper explores the typical fermentation methods for fruit and vegetable juices, investigates the bioactive components, functional activities, and the influence of fermentation on enhancing the quality of fruit and vegetable juices. The insights derived from this study carry significant implications for guiding the development of fermented fruit and vegetable juice industry.

Evaluation of immunomodulatory potential of probiotic conditioned medium on murine macrophages

Probiotics are a mixture of beneficial live bacteria and/or yeasts that naturally exist in our bodies. Recently, numerous studies have focused on the immunostimulatory effects of single-species or killed multi-species probiotic conditioned mediums on macrophages. This study investigates the immunostimulatory effect of commercially available active, multi-species probiotic conditioned medium (CM) on RAW264.7 murine macrophages. The probiotic CM was prepared by culturing the commercially available probiotic in a cell-culture medium overnight at 37 °C, followed by centrifugation and filter-sterilization to be tested on macrophages. The immunostimulatory effect of different dilution percentages (50%, 75%, 100%) of CM was examined using the MTT assay, proinflammatory cytokine (tumor necrosis factor TNF-alpha) production in macrophages, migration, and phagocytosis assays. For all the examined CM ratios, the percentages of cell viability were > 80%. Regarding the migration scratch, TNF-alpha and phagocytosis assays, CM demonstrated a concentration-dependent immunostimulatory effect. However, the undiluted CM (100%) showed a significant (p-value < 0.05) stimulatory effect compared to the positive and negative controls. The findings suggest that the secretions and products of probiotics, as measured in the CM, may be closely associated with their immune-boosting effects. Understanding this relationship between probiotic secretions and immune function is crucial for further exploring the potential benefits of probiotics in enhancing overall health and well-being.

Similarities and differences: species and diet impact gut microbiota of captive pheasants

The fecal microbiota plays an important role in maintaining animal health and is closely related to host life activities. In recent years, there have been an increasing number of studies on the fecal microbiota from birds. An exploration of the effects of species and living environments on the composition of gut microbiota will provide better protection for wildlife. In this study, non-injury sampling and 16S rDNA high-throughput sequencing were used to investigate the bacterial composition and diversity of the fecal microbiota in silver pheasants (Lophura nycthemera) and golden pheasants (Chrysolophus pictus) from Tianjin Zoo and Beijing Wildlife Park. The results showed that the abundance of Firmicutes was the highest in all fecal samples. At the genus level, Bacteroides was the common dominant bacteria, while there were some differences in other dominant bacteria genera. There were significant differences in fecal microbial composition between the golden pheasants from Tianjin Zoo and Beijing Wildlife Park. The metabolic analysis and functional prediction suggested that the gut microbiota composition and host metabolism were influenced by dietary interventions and living conditions. The results of this study provide the basis for further research of intestinal microbial of L. nycthemera and C. pictus, and valuable insights for conservation of related species.

Multi-omics analysis of the gut microbiome and metabolites associated with the psychoneurological symptom cluster in children with cancer receiving chemotherapy

BACKGROUND

Children with cancer receiving chemotherapy commonly report a cluster of psychoneurological symptoms (PNS), including pain, fatigue, anxiety, depression, and cognitive dysfunction. The role of the gut microbiome and its functional metabolites in PNS is rarely studied among children with cancer. This study investigated the associations between the gut microbiome-metabolome pathways and PNS in children with cancer across chemotherapy as compared to healthy children.

METHODS

A case-control study was conducted. Cancer cases were recruited from Children's Healthcare of Atlanta and healthy controls were recruited via flyers. Participants reported PNS using the Pediatric Patient-Reported Outcomes Measurement Information System. Data for cases were collected pre-cycle two chemotherapy (T0) and post-chemotherapy (T1), whereas data for healthy controls were collected once. Gut microbiome and its metabolites were measured using fecal specimens. Gut microbiome profiling was performed using 16S rRNA V4 sequencing, and metabolome was performed using an untargeted liquid chromatography-mass spectrometry approach. A multi-omics network integration program analyzed microbiome-metabolome pathways of PNS.

RESULTS

Cases (n = 21) and controls (n = 14) had mean ages of 13.2 and 13.1 years. For cases at T0, PNS were significantly associated with microbial genera (e.g., Ruminococcus, Megasphaera, and Prevotella), which were linked with carnitine shuttle (p = 0.0003), fatty acid metabolism (p = 0.001) and activation (p = 0.001), and tryptophan metabolism (p = 0.008). Megasphaera, clustered with aspartate and asparagine metabolism (p = 0.034), carnitine shuttle (p = 0.002), and tryptophan (p = 0.019), was associated with PNS for cases at T1. Gut bacteria with potential probiotic functions, along with fatty acid metabolism, tryptophan, and carnitine shuttle, were more clustered in cancer cases than the control network and this linkage with PNS needs further studies.

CONCLUSIONS

Using multi-omics approaches, this study indicated specific microbiome-metabolome pathways linked with PNS in children with cancer across chemotherapy. Due to limitations such as antibiotic use in cancer cases, these findings need to be further confirmed in a larger cohort.

Prophylactic application of vaginal lactic acid bacteria against urogenital pathogens and its prospective use in sanitary suppositories

Beneficial and pathogenic microbes coexist in the vaginal canal, where a diminishing population of lactic acid bacteria may cause recurring urogenital infections. Probiotic bacteria Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus vaginalis, and pathogenic microbes Enterococcus faecalis, Enterobacter cloacae, Shigella sp., Staphylococcus epidermidis, and Escherichia fergusonii were isolated from vaginal swabs. Lactobacillus sp. and their probiotic culture free supernatant (PCFS) inhibited the growth of the above-mentioned urogenital pathogens. L. crispatus produced both lactic acid and hydrogen peroxide, exhibiting the best antimicrobial potential against the studied pathogens. Lyophilized L. crispatus had a shelf life of 12 months and the lyophilized PCFS also retained its antibacterial property with a minimum inhibition concentration of 1 μg/μL. Carboxy-methyl cellulose-alginate, a green alternative to super-absorbent polymers, was encapsulated with L. crispatus cells. The probiotic in its encapsulated state retained its viability for 21 days, and the bead showed 30% solvent absorptive capacity. PCFS-laced non-woven fabric displayed antibacterial property with no change in its physicochemical properties. These probiotic and postbiotic formulations have excellent prophylactic potential for urogenital infections. Such formulations can be exploited as additives in sanitary suppositories to enhance vaginal health.

Efficacy of Lactiplantibacillus plantarum PBS067, Bifidobacterium animalis subsp. lactis BL050, and Lacticaseibacillus rhamnosus LRH020 in the Amelioration of Vaginal Microbiota in Post-Menopausal Women: A Prospective Observational Clinical Trial

The menopausal transition marks a significant physiological shift in women. Menopause-related symptoms can significantly affect a woman's quality of life and probiotics have emerged as a promising avenue. This study aims to investigate the benefits of probiotics in improving vaginal well-being and microbiota composition in post-menopausal women. A prospective observational clinical trial was carried out enrolling 50 post-menopausal healthy women, aged between 45 and 65 years old, taking a supplement containing Lactiplantibacillus plantarum PBS067, Bifidobacterium animalis subsp. lactis BL050, and Lacticaseibacillus rhamnosus LRH020 (3B CFU/day) for 28 days. Vaginal swabs were collected to evaluate microbiota fluctuation and the inflammatory pattern was recorded. A Vaginal Health Index was provided to evaluate vaginal well-being throughout the trial. Clinical outcomes revealed a decrease in menopausal symptoms. Significant improvements were observed across various parameters: a 50% enhancement in the VHI score (p < 0.0001), alongside substantial reductions in inflammatory cytokine levels. An 87.8% decrease in IL-6, 57.6% in IL-1β, and 40.8% in TNF-α was observed (p < 0.05). Moreover, the probiotic intervention facilitated the restoration of vaginal microbiota, evidenced by an increase in lactobacilli abundance. In conclusion, the combination of these specific probiotic strains, previously clinically tested in childbearing-age women, showed to be effective also for post-menopausal women.

Simulated spaceflight-induced cardiac remodeling is modulated by gut microbial-derived trimethylamine N-oxide

Spaceflight is physically demanding and can negatively affect astronauts' health. It has been shown that the human gut microbiota and cardiac function are affected by spaceflight and simulated spaceflight. This study investigated the effects of the gut microbiota on simulated spaceflight-induced cardiac remodeling using 10° of head-down bed rest (HDBR) in rhesus macaques and 30° of hindlimb unloading (HU) in mice. The gut microbiota, fecal metabolites, and cardiac remodeling were markedly affected by HDBR in macaques and HU in mice, cardiac remodeling in control mice was affected by the gut microbiota of HU mice and that of HU mice was protected by the gut microbiota of control mice, and there was a correlation between cardiac remodeling and the gut microbial-derived metabolite trimethylamine N-oxide. These findings suggest that spaceflight can affect cardiac remodeling by modulating the gut microbiota and fecal metabolites.

In Vitro Evaluation of Probiotic Properties of Two Novel Probiotic Mixtures, Consti-Biome and Sensi-Biome

Changes in the gut microbiome cause recolonization by pathogens and inflammatory responses, leading to the development of intestinal disorders. Probiotics administration has been proposed for many years to reverse the intestinal dysbiosis and to enhance intestinal health. This study aimed to evaluate the inhibitory effects of two newly designed probiotic mixtures, Consti-Biome and Sensi-Biome, on two enteric pathogens Staphylococcus aureus and Escherichia coli that may cause intestinal disorders. Additionally, the study was designed to evaluate whether Consti-Biome and Sensi-Biome could modulate the immune response, produce short-chain fatty acids (SCFAs), and reduce gas production. Consti-Biome and Sensi-Biome showed superior adhesion ratios to HT-29 cells and competitively suppressed pathogen adhesion. Moreover, the probiotic mixtures decreased the levels of pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-6 and IL-1β. Cell-free supernatants (CFSs) were used to investigate the inhibitory effects of metabolites on growth and biofilms of pathogens. Consti-Biome and Sensi-Biome CFSs exhibited antimicrobial and anti-biofilm activity, where microscopic analysis confirmed an increase in the number of dead cells and the structural disruption of pathogens. Gas chromatographic analysis of the CFSs revealed their ability to produce SCFAs, including acetic, propionic, and butyric acid. SCFA secretion by probiotics may demonstrate their potential activities against pathogens and gut inflammation. In terms of intestinal symptoms regarding abdominal bloating and discomfort, Consti-Biome and Sensi-Biome also inhibited gas production. Thus, these two probiotic mixtures have great potential to be developed as dietary supplements to alleviate the intestinal disorders.

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.

Novel Dietary Approach with Probiotics, Prebiotics, and Synbiotics to Mitigate Antimicrobial Resistance and Subsequent Out Marketplace of Antimicrobial Agents: A Review

Antimicrobial resistance (AMR) is a significant public health concern worldwide. The continuous use and misuse of antimicrobial agents have led to the emergence and spread of resistant strains of bacteria, which can cause severe infections that are difficult to treat. One of the reasons for the constant development of new antimicrobial agents is the need to overcome the resistance that has developed against existing drugs. However, this approach is not sustainable in the long term, as bacteria can quickly develop resistance to new drugs as well. Additionally, the development of new drugs is costly and time-consuming, and there is no guarantee that new drugs will be effective or safe. An alternative approach to combat AMR is to focus on improving the body's natural defenses against infections by using probiotics, prebiotics, and synbiotics, which are helpful to restore and maintain a healthy balance of bacteria in the body. Probiotics are live microorganisms that can be consumed as food or supplements to promote gut health and improve the body's natural defenses against infections. Prebiotics are non-digestible fibers that stimulate the growth of beneficial bacteria in the gut, while synbiotics are a combination of probiotics and prebiotics that work together to improve gut health. By promoting a healthy balance of bacteria in the body, these can help to reduce the risk of infections and the need for antimicrobial agents. Additionally, these approaches are generally safe and well tolerated, and they do not contribute to the development of AMR. In conclusion, the continuous development of new antimicrobial agents is not a sustainable approach to combat AMR. Instead, alternative approaches such as probiotics, prebiotics, and synbiotics should be considered as they can help to promote a healthy balance of bacteria in the body and reduce the need for antibiotics.

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.

Effects of Probiotic Supplementation on Exercise and the Underlying Mechanisms

Long-term, high-intensity exercise can trigger stress response pathways in multiple organs, including the heart and lungs, gastrointestinal tract, skeletal muscle, and neuroendocrine system, thus affecting their material and energy metabolism, immunity, oxidative stress, and endocrine function, and reducing exercise function. As a natural, safe, and convenient nutritional supplement, probiotics have been a hot research topic in the field of biomedical health in recent years. Numerous studies have shown that probiotic supplementation improves the health of the body through the gut-brain axis and the gut-muscle axis, and probiotic supplementation may also improve the stress response and motor function of the body. This paper reviews the progress of research on the role of probiotic supplementation in material and energy metabolism, intestinal barrier function, immunity, oxidative stress, neuroendocrine function, and the health status of the body, as well as the underlying mechanisms.

The Combined Effect of Potential Probiotic Bacillus licheniformis MCC 2514 and Bifidobacterium breve NCIM 5671 Towards Anti-inflammatory Activity on HT-29 Cell Lines

Probiotics are considered a natural source for treating many intestinal disorders, which deliver health benefits in different ways. The study aims to evaluate the immunomodulatory gene expression on HT-29 cell line using Bacillus licheniformis MCC 2514 and Bifidobacterium breve NCIM 5671 as a single culture and in combination. Upon inflammation induced by LPS, the combination of bacteria downregulated the pro-inflammatory cytokines IL-1α (13.4), IL-12 (14.6), IL-8 (2.6), and IL-6 (1.9), and in contrast, TNF-α (21.2) folds has upregulated. However, anti-inflammatory genes such as IL-4 (0.6), IL-10 (2.9), TGF-2 (92.2), and TGF-3 (85.8) folds were upregulated. The combination of bacteria against oxidative stress downregulated the pro-inflammatory cytokines such as IL-1α & β, IL-6, IL-8, IL-12, and IL-18, and upregulated the anti-inflammatory cytokines IL-10, IL-4, TGF-2, and TGF-3. On the introduction of Kocuria rhizophila, the pro-inflammatory cytokines were upregulated. On supplementation of B. licheniformis and B. breve, the upregulated pro-inflammatory cytokines were decreased, and anti-inflammatory cytokines such as IL-4 (6.2), IL-10 (23.5), TGF-2 (166), and TGF-3(28.4) folds were increased. However, gene expression of toll-like receptor-2 was found high (26 folds) upon introducing probiotic bacteria. ELISA results of Interferon-γ found that the expression was higher (7.19 ng/mL) on the introduction of both the bacteria in combination. The higher anti-inflammatory activity was observed when potential probiotic bacteria were used in combination compared to a single culture. Overall study indicates that the combination of aerobic B. licheniformis and anaerobic B. breve has an anti-inflammatory activity that can sustain an excellent gastrointestinal environment during pathogen invasion and inflammation.

Dietary intake of table olives exerts antihypertensive effects in association with changes in gut microbiota in spontaneously hypertensive rats

Arbequina table olive (AO) consumption lowers blood pressure (BP) in spontaneously hypertensive rats (SHR). This study evaluates whether dietary supplementation with AO induced changes in the gut microbiota that are consistent with the purported antihypertensive effects. Wistar-Kyoto rats (WKY-c) and SHR-c received water, while SHR-o were supplemented by gavage with AO (3.85 g kg^-1) for 7 weeks. Faecal microbiota was analysed by 16S rRNA gene sequencing. SHR-c showed increased Firmicutes and decreased Bacteroidetes compared to WKY-c. AO supplementation in SHR-o decreased BP by approximately 19 mmHg, and reduced plasmatic concentrations of malondialdehyde and angiotensin II. Moreover, reshaped faecal microbiota associated with antihypertensive activity by lowering Peptoniphilus and increasing Akkermansia, Sutterella, Allobaculum, Ruminococcus, and Oscillospira. Also promoted the growth of probiotic strains of Lactobacillus and Bifidobacterium and modified the relationship of Lactobacillus with other microorganisms, from competitive to symbiotic. In SHR, AO promotes a microbiota profile compatible with the antihypertensive effects of this food.

Evaluation of Antimicrobial, Antiadhesive and Co-Aggregation Activity of a Multi-Strain Probiotic Composition against Different Urogenital Pathogens

The urogenital microbiota is dominated by Lactobacillus that, together with Bifidobacterium, creates a physiological barrier counteracting pathogen infections. The aim of this study was to evaluate the efficacy of a multi-strain probiotic formulation (Lactiplantibacillus plantarum PBS067, Lacticaseibacillus rhamnosus LRH020, and Bifidobacterium animalis subsp. lactis BL050) to inhibit adhesion and growth of urogenital pathogens. The antimicrobial and antiadhesive properties of the probiotic strains and their mixture were evaluated on human vaginal epithelium infected with Candida glabrata, Neisseria gonorrheae, Trichomonas vaginalis, and Escherichia coli-infected human bladder epithelium. The epithelial tissue permeability and integrity were assessed by transepithelial/transendothelial electrical resistance (TEER). Co-aggregation between probiotics and vaginal pathogens was also investigated to elucidate a possible mechanism of action. The multi-strain formulation showed a full inhibition of T. vaginalis, and a reduction in C. glabrata and N. gonorrheae growth. A relevant antimicrobial activity was observed for each single strain against E. coli. TEER results demonstrated that none of the strains have negatively impaired the integrity of the 3D tissues. All the probiotics and their mixture were able to form aggregates with the tested pathogens. The study demonstrated that the three strains and their mixture are effective to prevent urogenital infections.

Synergistic Antioxidant Effect of Prebiotic Ginseng Berries Extract and Probiotic Strains on Healthy and Tumoral Colorectal Cell Lines

Oxidative stress caused by reactive oxygen species (ROS, O2•−, HO•, and H2O2) affects the aging process and the development of several diseases. A new frontier on its prevention includes functional foods with both specific probiotics and natural extracts as antioxidants. In this work, Panax ginseng C.A. Meyer berries extract was characterized for the presence of beneficial molecules (54.3% pectin-based polysaccharides and 12% ginsenosides), able to specifically support probiotics growth (OD600nm > 5) with a prebiotic index of 0.49. The administration of the extract to a probiotic consortium induced the production of short-chain fatty acids (lactic, butyric, and propionic acids) and other secondary metabolites derived from the biotransformation of Ginseng components. Healthy and tumoral colorectal cell lines (CCD841 and HT-29) were then challenged with these metabolites at concentrations of 0.1, 0.5, and 1 mg/mL. The cell viability of HT-29 decreased in a dose-dependent manner after the exposition to the metabolites, while CCD841 vitality was not affected. Regarding ROS production, the metabolites protected CCD841 cells, while ROS levels were increased in HT-29 cells, potentially correlating with the less functionality of glutathione S-transferase, catalase, and total superoxide dismutase enzymes, and a significant increase in oxidized glutathione.

Genomic and Biochemical Characterization of Bifidobacterium pseudocatenulatum JCLA3 Isolated from Human Intestine

Bifidobacteria have been investigated due to their mutualistic microbe-host interaction with humans throughout their life. This work aims to make a biochemical and genomic characterization of Bifidobacterium pseudocatenulatum JCLA3. By multilocus analysis, the species of B. pseudocatenulatum JCLA3 was established as pseudocatenulatum. It contains one circular genome of 2,369,863 bp with G + C content of 56.6%, no plasmids, 1937 CDSs, 54 tRNAs, 16 rRNAs, 1 tmRNA, 1 CRISPR region, and 401 operons predicted, including a CRISPR-Cas operon; it encodes an extensive number of enzymes, which allows it to utilize different carbohydrates. The ack gene was found as part of an operon formed by xfp and pta genes. Two genes of ldh were found at different positions. Chromosomally encoded resistance to ampicillin and cephalothin, non-hemolytic activity, and moderate inhibition of Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 6538 were demonstrated by B. pseudocatenulatum JCLA3; it can survive 100% in simulated saliva, can tolerate primary and secondary glyco- or tauro-conjugated bile salts but not in a mix of bile; the strain did not survive at pH 1.5-5. The cbh gene coding to choloylglycine hydrolase was identified in its genome, which could be related to the ability to deconjugate secondary bile salts. Intact cells showed twice as much antioxidant activity than debris. B. pseudocatenulatum JCLA3 showed 49% of adhesion to Caco-2 cells. The genome and biochemical analysis help to elucidate further possible biotechnological applications of B. pseudocatenulatum JCLA3.

Characterization of the Biological Activities of a New Polyphenol-Rich Extract from Cinnamon Bark on a Probiotic Consortium and Its Action after Enzymatic and Microbial Fermentation on Colorectal Cell Lines

Cinnamon polyphenols are known as health-promoting agents. However, their positive impact depends on the extraction method and their bioaccessibility after digestion. In this work, cinnamon bark polyphenols were extracted in hot water and subjected to an in vitro enzymatic digestion. After a preliminary characterization of total polyphenols and flavonoids (respectively 520.05 ± 17.43 µgGAeq/mg and 294.77 ± 19.83 µgCATeq/mg powder extract), the extract antimicrobial activity was evidenced only against Staphylococcus aureus and Bacillus subtilis displaying a minimum inhibition growth concentration value of 2 and 1.3 mg/mL, respectively, although it was lost after in vitro extract digestion. The prebiotic potential was evaluated on probiotic Lactobacillus and Bifidobacterium strains highlighting a high growth on the in vitro digested cinnamon bark extract (up to 4 × 10⁸ CFU/mL). Thus, the produced SCFAs and other secondary metabolites were extracted from the broth cultures and determined via GC-MSD analyses. The viability of healthy and tumor colorectal cell lines (CCD841 and SW480) was assayed after the exposition at two different concentrations (23 and 46 µgGAeq/mL) of the cinnamon extract, its digested, and the secondary metabolites produced in presence of cinnamon extract or its digested, showing positive protective effects against a tumorigenic condition.

Effects of Inulin-Based Prebiotics Alone or in Combination with Probiotics on Human Gut Microbiota and Markers of Immune System: A Randomized, Double-Blind, Placebo-Controlled Study in Healthy Subjects

The gut microbiota is implicated in diverse interactions affecting human health. The present study reports a randomized, double-blind, placebo-controlled clinical study conducted by administering a new synbiotic formulation composed of two Lactobacillus strains (L. plantarum and L. acidophilus) and one Bifidobacterium strain (B. animalis subsp. lactis) and two types of fructans (fructo-oligosaccharides with a degree of polymerization of 3–5 and inulin-type fructans with 10 DP). The effects of this synbiotic were evaluated on healthy subjects for 28 days and the maintenance of its efficacy was evaluated at the end of a follow-up period of 28 days. The synbiotic treatment contributes to higher biodiversity of the gut microbiota, increasing the community richness with respect to the group with the prebiotics alone and the placebo group. Its positive effect is also reflected in the variation of microbial community structure favoring the beneficial short-chain fatty acids bacterial producers. The amelioration of the health status of the subjects was also established by the reduction of common infectious disease symptom incidence, the stimulation of the gut immune system showing a noteworthy variation of fecal β-defensin2 and calprotectin levels, and the modulation of the response of the respiratory tract’s immune system by salivary IgA as well as total antioxidant capacity biomarkers.

Assessment of the Effects of the Synbiotic Combination of Bifidobacterium longum subsp. infantis CECT 7210 and Oligofructose-Enriched Inulin Against Digestive Bacterial Infections in a Piglet Model

The use of bifidobacteria as probiotics has proven to be beneficial in gastroenteric infections. Furthermore, prebiotics such as inulin can enhance the survival and growth of these bacteria. Two trials were performed to evaluate the effects of the administration of Bifidobacterium longum subsp. infantis CECT 7210 and oligofructose-enriched inulin against Salmonella enterica serovar Typhimurium or enterotoxigenic Escherichia coli (ETEC) F4. A total of 72 (Salmonella trial) and 96 (ETEC F4 trial) weaned piglets were used in a 2 × 2 design (with or without synbiotic, inoculated or not with the pathogen). After adaptation, animals were orally inoculated. Performance and clinical signs were evaluated. On days 4 and 8 (Salmonella trial) and 3 and 7 (ETEC F4 trial) post-inoculation (PI), one animal per pen was euthanized. Blood, digestive content and tissue samples were collected and microbiological counts, fermentation products, serum inflammatory markers and ileum histomorphometry analysis were performed. Both challenges had an impact on faecal consistency (p < 0.001), including the faecal shedding of Salmonella and increased numbers of enterobacteria and coliforms. The synbiotic administration did not have any effect on pathogen loads but induced changes in the fermentation profile, such as increased valeric acid in both trials as well as decreased acetic acid, except for Salmonella-challenged animals. The effect on propionate varied among trials, increasing in challenged synbiotic-treated pigs and decreasing in non-challenged ones in the Salmonella trial (P interaction = 0.013), while the opposed occurred in the ETEC F4 trial (P interaction = 0.013). The administration of the synbiotic increased intraepithelial lymphocytes (IEL; p = 0.039) on day 8 PI in the Salmonella trial and a similar trend occurred in non-challenged pigs in the ETEC F4 trial (P interaction = 0.086). The results did not provide evidence of reduced pathogen load with the synbiotic, although a modulation in fermentative activity could be identified depending on the challenge. Consistent increases were found in IEL, suggesting that this synbiotic combination has some immunomodulatory properties.

Identification of a Novel Biosurfactant with Antimicrobial Activity Produced by Rhodococcus opacus R7

Rhodococcus members excrete secondary metabolites, especially compounds which act as biosurfactants. In this work, we demonstrated the ability of Rhodococcus opacus R7 to produce a novel bioactive compound belonging to the class of biosurfactants with antimicrobial properties during the growth on naphthalene. Chemical and biochemical analyses of the isolated compound demonstrated that the biosurfactant could be classified as a hydrophobic peptide. The ESI-full mass spectrometry revealed that the isolated biosurfactant showed a molecular weight of 1292 Da and NMR spectra evidenced the composition of the following amino acid residues: Ala, Thr, Asp, Gly, Ser. Surfactant activity of the R. opacus R7 compound was quantified by the critical micelle dilution (CMD) method and the critical micelle concentration (CMC) was estimated around 20 mg L⁻¹ with a corresponding surface tension of 48 mN m⁻¹. Moreover, biological assays demonstrated that R. opacus R7 biosurfactant peptide exhibited antimicrobial activity against Escherichia coli ATCC 29522 and Staphylococcus aureus ATCC 6538 with the minimum inhibition growth concentration (MIC) values of 2.6 mg mL⁻¹ and 1.7 mg mL⁻¹, respectively. In this study for the first time, a hydrophobic peptide with both biosurfactant and antimicrobial activity was isolated from a bacterium belonging to Rhodococcus genus.

Prebiotic Effect of Maitake Extract on a Probiotic Consortium and Its Action after Microbial Fermentation on Colorectal Cell Lines

Maitake (Grifola frondosa) is a medicinal mushroom known for its peculiar biological activities due to the presence of functional components, including dietary fibers and glucans, that can improve human health through the modulation of the gut microbiota. In this paper, a Maitake ethanol/water extract was prepared and characterized through enzymatic and chemical assays. The prebiotic potential of the extract was evaluated by the growth of some probiotic strains and of a selected probiotic consortium. The results revealed the prebiotic properties due to the stimulation of the growth of the probiotic strains, also in consortium, leading to the production of SCFAs, including lactic, succinic, and valeric acid analyzed via GC-MSD. Then, their beneficials effect were employed in evaluating the vitality of three different healthy and tumoral colorectal cell lines (CCD841, CACO-2, and HT-29) and the viability rescue after co-exposure to different stressor agents and the probiotic consortium secondary metabolites. These metabolites exerted positive effects on colorectal cell lines, in particular in protection from reactive oxygen species.

Prebiotics/Probiotics Mixture Induced Changes in Cecal Microbiome and Intestinal Morphology Alleviated the Loperamide-Induced Constipation in Rat

The aim of this study was to investigate the effect of a mixture of multi-strain probiotics and prebiotics on loperamide-induced constipation in Sprague-Dawley rats. A multi-strain probiotics alone (loperamide-induced group with multi-strain probiotics mixture group; Lop-Pro) and a mixture of multi-strain probiotics and prebiotics (loperamide-induced group with multi-strain probiotics and prebiotics mixture group; Lop-Pro/Pre) were administered orally after inducing constipation. The fecal water content was significantly higher (by 42%) in the Lop-Pro/Pre group (33.5%) than in the loperamide-induced group (Lop) (23.7%) (p<0.05). The intestinal mucosal thickness, crypt cell area, and interstitial cells of Cajal area were significantly higher in the Lop-Pro/Pre group compared to the Lop group by 16.4%, 20.6%, and 42.3%, respectively. Additionally, the total short-chain fatty acid content was significantly increased in the Lop-Pro and Lop-Pro/Pre groups by 56.4% and 54.2%, respectively, compared with the Lop group. The Lop-Pro and Lop-Pro/Pre groups recovered loperamide-induced alteration in Bacteroidetes and Verrucomicrobia abundance among intestinal microbiota, whereas the Lop-Pro/Pre group recovered Akkermansia, Lactobacillus, Clostridium, Bacteroides, and Oscillibacter abundance. Moreover, the relative abundance of Oscillibacter and Clostridium was significantly different in the Lop-Pro/Pre group compared to the Lop group. Collectively, administration of synbiotics rather than multi-strain probiotics alone is effective in alleviating constipation.

Probiotic Properties and Immunomodulatory Activity of Lactobacillus Strains Isolated from Dairy Products

Lactobacilli species are an effective biotherapeutic alternative against bacterial infections and intestinal inflammatory disorders. However, it is important to evaluate their beneficial properties, before considering them as probiotics for medical use. In this study we evaluated some probiotic properties of Lactobacillus rhamnosus GG, Lactobacillus rhamnosus KLSD, Lactobacillus helveticus IMAU70129, and Lactobacillus casei IMAU60214 previously isolated from dairy products and as control Lactobacillus casei Shirota. Experimental evaluations revealed that all strains expressed hydrophobicity (25–40%), auto-aggregation (55–60%), NaCl tolerance (1–4%), adhesion to Caco-2 cells (25–33%), partial inhibition on adherence of Escherichia coli ATCC 35218, Salmonella Typhimurium ATCC 14028, and Staphylococcus aureus ATCC 23219. Cell-free supernatants (CFS) of Lactobacilli also inhibit growth of these pathogens. In immunomodulatory properties a reduction of interleukin-8 (IL-8) and nitric oxide (NO) release was observed in assays with Caco-2 cells stimulated with interleukin-1β (1 ng/mL), or lipopolysaccharide (0.1 µg/mL). On the other hand, the damage induced to Caco-2 cells with sodium dodecyl sulfate (SDS) was attenuated when the cultured cells were pretreated with L. rhamnosus KLDS, L. helveticus IMAU70129 and L. casei IMAU60214. These Lactobacilli possess probiotic properties determined by both an antagonistic activity on pathogenic bacteria and reduction in the inflammatory response of cells treated with SDS, a pro-inflammatory stimulant.

Whole genome and acid stress comparative transcriptome analysis of Lactiplantibacillus plantarum ZDY2013

Previous study has reported that Lactiplantibacillus plantarum ZDY2013 which was screened from traditional Chinese fermented soybeans has a strong acid resistance. The purpose of this study was to uncover the genes potentially related to its genetic adaptation and probiotic profiles, based on comparative genomic and comparative transcriptome analysis. We got the basic information about L. plantarum ZDY2013 and identified genes which are related to genetic adaptation and probiotic profiles, including carbohydrate transport and metabolism, cell wall/membrane/envelope biogenesis, proteolytic enzyme systems and amino acid biosynthesis, CRISPR adaptive immunity, stress responses, ability to adhere to the host intestinal wall, exopolysaccharide (EPS) biosynthesis, and bacteriocin biosynthesis. Comparative transcriptome showed CK group (normal MRS culture L. plantarum ZDY2013) and SCL group (pH 3.0 MRS culture L. plantarum ZDY2013) had 652 significant differentially expressed genes including 310 up-regulated genes and 342 down-regulated genes. Besides that, these genes had been classified through KEGG and GO functional annotation. In addition, we also found top 20 KEGG pathways adjusted to acid stress. Then, some genes were selected to verify the transcriptome analysis and explore the mechanism of how L. plantarum ZDY2013 tolerate acid stress. We found that some genes of ABC transporter, phosphotransferase system, oxidation reduction process, membrane transporter and phosphorylation metabolism process had a significant change. These results suggested that comparative characterization of the L. plantarum ZDY2013 genome and transcriptome provided the genetic basis for further elucidating the functional mechanisms of it.

Isolation and Genetic Identification of Endophytic Lactic Acid Bacteria From the Amazonian Açai Fruits: Probiotics Features of Selected Strains and Their Potential to Inhibit Pathogens

The açai palm (Euterpe oleracea) is native to the Amazon basin, a humid tropical forest. High levels of total mesophilic bacteria with high diversity have been consistently reported in açai fruits. As local consumers have few digestive problems, the results of the present study reveal the lactic acid bacteria (LAB) recovered from açai fruits with characteristics that suggest they are possible candidates for probiotics and antagonistic potential against pathogens for the first time. Açai fruits were sampled from five different locations in the Eastern Amazonia floodplains. Sixty-six isolates were recovered from fruits and tested for some probiotic characteristics following FAO/WHO guidelines. Approximately 65% of the isolates showed no catalase or oxidase activity, Gram-positive staining or cocci and bacilli cell morphology. Furthermore, 48% of the isolates demonstrated preliminary characteristics that suggest safety for use, as they presented no coagulase enzyme activity or gamma-hemolysis. These strains were identified as belonging to the genera Lactiplantibacillus and Pediococcus, and 32 strains also presented resistance to vancomycin, ciprofloxacin and streptomycin. In addition, 28 isolates showed a survival rate, expressed as log cycle reduction, higher than 0.9 under gastric conditions (pH 2). All strains tested positive in bile salts deconjugation tests and showed a survival rate higher than 0.8 in the presence of this salt. Regarding antimicrobial activity against pathogens, all strains were able to inhibit Salmonella Typhimurium (ATCC^® 14028^TM) and 97% were capable of inhibiting Escherichia coli (ATCC^® 25922^TM). Concerning the results of in vitro antagonistic assays, three isolates (B125, B135, and Z183 strains) were selected for antagonistic tests using açai juice contaminated with these two pathogens. All tested LAB strains were able to inhibit pathogen growth in açai juice. In summary, açai fruits are a potential source of LAB isolates to be investigated as probiotics.

Characterization of the Intestinal Microbiota of Broiler Breeders With Different Egg Laying Rate

The gastrointestinal microbiota plays a pivotal role in maintaining animal health, immunity and reproductive performances. However, literature about the relationship between microbiota and reproductive performance is limited. The aim of the present study was to determine differences in the intestinal microbiota of broiler breeders with different egg laying rate. A total of 200 AA+ parent broiler breeders (41-week-old) were separated into two groups according to their different egg laying rate [average egg laying rate group (AR: 78.57 ± 0.20%) and high egg laying rate group (HR: 90.79 ± 0.43%). Feed conversion ratio (FCR), ovary cell apoptosis rate (ApoCR) and relative abdominal fat weight were lower (p = 0.01), while the hatchability rate of qualified egg was higher (p = 0.04) in HR group than that in AR group. Phascolarctobacterium abundance were lower (p = 0.012) in ileum of HR birds. Romboutsia (genus) in ileum was negatively related to the feed efficiency (r = -0.58, p < 0.05), Firmicutes (phylum) and Lactobacillus (genus) abundances in cecum were positively related to the egg laying rate (ELR) (r = 0.35 and 0.48, p < 0.05), feed efficiency (r = 0.42 and 0.43, p < 0.05), while Spirochaetes (phylum) and Sphaerochaeta (genus) abundances in cecum were negatively related to the ELR (r = -0.43 and -0.70, p < 0.05), feed efficiency (r = 0.54 and 0.48, p < 0.05), and positively related to ApoCR (r = 0.46 and 0.47, p < 0.05). Our results suggested that microbiota, such as Firmicutes (phylum) and Lactobacillus (genus) have positive relationship, while Spirochaetes (phylum) and Romboutsia (genus) abundances exert negative relationship with broiler breeders' reproductive performances.

Immunometabolism, Micronutrients, and Bariatric Surgery: The Use of Transcriptomics and Microbiota-Targeted Therapies

BACKGROUND

Obesity is associated with the gut microbiota and decreased micronutrient status. Bariatric surgery is a recommended therapy for obesity. It can positively affect the composition of the gut bacteria but also disrupt absorption of nutrients. Low levels of micronutrients can affect metabolic processes, like glycolysis, TCA cycle, and oxidative phosphorylation, that are associated with the immune system also known as immunometabolism.

METHODS

MEDLINE, PUBMED, and Google Scholar were searched. Articles involving gut microbiome, micronutrient deficiency, gut-targeted therapies, transcriptome analysis, micronutrient supplementation, and bariatric surgery were included.

RESULTS

Studies show that micronutrients play a pivotal role in the intestinal immune system and regulating immunometabolism. Research demonstrates that gut-targeting therapies may improve the microbiome health for bariatric surgery populations. There is limited research that examines the role of micronutrients in modulating the gut microbiota among the bariatric surgery population.

CONCLUSIONS

Investigations are needed to understand the influence that micronutrient deficiencies have on the gut, particularly immunometabolism. Nutritional transcriptomics shows great potential in providing this type of analysis to develop gut-modulating therapies as well as more personalized nutrition recommendations for bariatric surgery patients.

The Potential Effects of Probiotics and ω-3 Fatty Acids on Chronic Low-Grade Inflammation

Chronic low-grade inflammation negatively impacts health and is associated with aging and obesity, among other health outcomes. A large number of immune mediators are present in the digestive tract and interact with gut bacteria to impact immune function. The gut microbiota itself is also an important initiator of inflammation, for example by releasing compounds such as lipopolysaccharides (LPS) that may influence cytokine production and immune cell function. Certain nutrients (e.g., probiotics, ω-3 fatty acids [FA]) may increase gut microbiota diversity and reduce inflammation. Lactobacilli and Bifidobacteria, among others, prevent gut hyperpermeability and lower LPS-dependent chronic low-grade inflammation. Furthermore, ω-3 FA generate positive effects on inflammation-related conditions (e.g., hypertriglyceridemia, diabetes) by interacting with immune, metabolic, and inflammatory pathways. Ω-3 FA also increase LPS-suppressing bacteria (i.e., Bifidobacteria) and decrease LPS-producing bacteria (i.e., Enterobacteria). Additionally, ω-3 FA appear to promote short-chain FA production. Therefore, combining probiotics with ω-3 FA presents a promising strategy to promote beneficial immune regulation via the gut microbiota, with potential beneficial effects on conditions of inflammatory origin, as commonly experienced by aged and obese individuals, as well as improvements in gut-brain-axis communication.

Effects of spaceflight on the composition and function of the human gut microbiota

Interaction between humans and the gut microbiota is important for human physiology. Here, the gut microbiota was analyzed via metagenomic sequencing, and the fluctuations in the gut microbiota under the conditions of spaceflight were characterized. The composition and function of the gut microbiota were substantially affected by spaceflight; however, individual specificity was uncompromised. We further confirmed the species fluctuations and functional genes from both missions. Resistance and virulence genes in the gut microbiota were affected by spaceflight, but the species attributions remained stable. Spaceflight markedly affected the composition and function of the human gut microbiota, implying that the human gut microbiota is sensitive to spaceflight.

The mechanisms and safety of probiotics against toxigenic clostridium difficile

INTRODUCTION

Toxigenic Clostridium difficile (C. difficile) is the main cause of antibiotic-associated diarrhea and can induce pseudomembranous colitis and infrequent toxic megacolon, which are potentially fatal. The standard antibiotic therapy for C. difficile infection (CDI) is limited by antibiotics' broad spectrum and further disruptive effects on indigenous microbiota. Probiotics may offer a prospective and alternative strategy for the prevention and treatment of CDI.

AREAS COVERED

In this article, the mechanisms implying the probiotic effect against C. difficile and the safety profile highlighting the patient groups with inappropriate application of probiotics were reviewed from 2015 to 2020.

EXPERT OPINION

Although many strains with ability against C. difficile have been reported, the usage of probiotics for CDI prevention and/or treatment is scarce since the number of clinical trials is not sufficient to prove probiotics' efficacy and safety in CDI treatment, especially for premature infant and immunocompromised patient. Especially, there are few well-defined clinical studies supporting safety of probiotics for CDI. A few strains from Lactobacillus and Saccharomyces genus have been studied more extensively than other probiotic strains through clinical trials for CDI. Thus, more clinical intervention studies regarding the benefit and the comprehensive safety assessments of probiotics for CDI are needed.

Bifidobacteria cell wall-derived exo-polysaccharides, lipoteichoic acids, peptidoglycans, polar lipids and proteins - their chemical structure and biological attributes

A variety of health benefits has been documented to be associated with the consumption of probiotic bacteria, namely bifidobacteria and lactobacilli. Thanks to the scientific advances in recent years we are beginning to understand the molecular mechanisms by which bacteria in general and probiotic bacteria in particular act as host physiology and immune system modulators. More recently, the focus has shifted from live bacteria towards bacteria-derived defined molecules, so called postbiotics. These molecules may represent safer alternative compared to the live bacteria while retaining the desired effects on the host. The excellent source of effector macromolecules is the bacterial envelope. It contains compounds that are pivotal in the adhesion phenomenon, provide direct bacteria-to-host signaling capacity and the associated physiological impact and immunomodulatory properties of bacteria. Here we comprehensively review the structure and biological role of Bifidobacterium surface and cell wall molecules: exopolysaccharides, cell wall polysaccharides, lipoteichoic acids, polar lipids, peptidoglycans and proteins. We discuss their involvement in direct signaling to the host cells and their described immunomodulatory effects.

An examination of data from the American Gut Project reveals that the dominance of the genus Bifidobacterium is associated with the diversity and robustness of the gut microbiota

Bifidobacterium and Lactobacillus are beneficial for human health, and many strains of these two genera are widely used as probiotics. We used two large datasets published by the American Gut Project (AGP) and a gut metagenomic dataset (NBT) to analyze the relationship between these two genera and the community structure of the gut microbiota. The meta-analysis showed that Bifidobacterium, but not Lactobacillus, is among the dominant genera in the human gut microbiota. The relative abundance of Bifidobacterium was elevated when Lactobacillus was present. Moreover, these two genera showed a positive correlation with some butyrate producers among the dominant genera, and both were associated with alpha diversity, beta diversity, and the robustness of the gut microbiota. Additionally, samples harboring Bifidobacterium present but no Lactobacillus showed higher alpha diversity and were more robust than those only carrying Lactobacillus. Further comparisons with other genera validated the important role of Bifidobacterium in the gut microbiota robustness. Multivariate analysis of 11,744 samples from the AGP dataset suggested Bifidobacterium to be associated with demographic features, lifestyle, and disease. In summary, Bifidobacterium members, which are promoted by dairy and whole-grain consumption, are more important than Lactobacillus in maintaining the diversity and robustness of the gut microbiota.

Extraction and Characterization of Inulin-Type Fructans from Artichoke Wastes and Their Effect on the Growth of Intestinal Bacteria Associated with Health

Globe artichoke is an intriguing source of indigestible sugar polymers such as inulin-type fructans. In this study, the effect of ultrasound in combination with ethanol precipitation to enhance the extraction of long chain fructans from artichoke wastes has been evaluated. The inulin-type fructans content both from bracts and stems was measured using an enzymatic fructanase-based assay, while its average degree of polymerization (DP) was determined by HPLC-RID analysis. Results show that this method provides artichoke extracts with an inulin-type fructans content of 70% with an average DP between 32 and 42 both in bracts and in stems. The prebiotic effect of long chain inulins from artichoke extract wastes was demonstrated by its ability to support the growth of five Lactobacillus and four Bifidobacterium species, previously characterized as probiotics. Besides, we considered the possibility to industrialize the process developing a simpler method for the production of inulin-type fructans from the artichoke wastes so that the artichoke inulin preparation could be suitable for its use in synbiotic formulations in combination with different probiotics for further studies including in vivo trials.

Identification of a bacteriocin-like compound from Lactobacillus plantarum with antimicrobial activity and effects on normal and cancerogenic human intestinal cells

In this paper, we demonstrate that the antimicrobial activity of L. plantarum PBS067 strain against antagonist microorganisms was mediated by the production of a bacteriocin-like compound secreted at the stationary phase of the growth. The novel bacteriocin-like compound, designed plantaricin P1053, was identified by using sorption–desorption method, butanol extraction and SEC-HPLC. The molecular mass of plantaricin P1053 was shown to be 1053 Da by ESI-MS analysis. Plantaricin P1053 exhibited a broad-spectrum antimicrobial activity against Gram-positive bacteria as S. aureus and Gram-negative bacteria as E. coli. In addition to the antimicrobial activity, the isolated bacteriocin-like compound showed effects on normal and cancerogenic epithelial intestinal cell lines through an enhancing of viability of healthy cells and a proliferation reduction of cancer cells. Moreover, in this paper we demonstrate that the isolated bacteriocin-like compound acts on healthy cells through the epidermal growth factor receptor (EGFR) pathways. In conclusion, plantaricin P1053 isolated from L. plantarum PBS067 strain could represent one of the first multifunctional bacteriocin-like compound acting on human epithelial intestinal cells.

In vitro fermentation of oligosaccharides obtained from enzymatic hydrolysis of Opuntia streptacantha mucilage

BACKGROUND

Among Cactaceae, the genus Opuntia is widely known for the use of its biomass as cattle fodder and in human nutrition (e.g. species such as Opuntia ficus indica and Opuntia streptacantha). In particular, O. streptacantha (OS) produces abundant mucilage and, hence, the characterization of its properties and nutritional value is important. Accordingly, determination of the dietary fiber content of the OS mucilage and the fermentability of its hydrolysis products (oligosaccharides, OLI) is important for developing new uses of the crop as a functional food.

RESULTS

The values for insoluble dietary fiber and soluble dietary fiber in the mucilage were 204.6 and 371.6 g kg^-1 , respectively. After hydrolysis of OS mucilage with α-amylase, three purified fractions of OLI were evaluated (OLI-A, OLI-B and OLI-C). OLI (1% w/v) stimulated the growth of the commercial probiotic strains (Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium animalis subsp. lactis) in vitro, showing behaviors similar to those of commercial inulin. The production of short chain fatty acids (SCFAs) in the fermentation broth was also determined. The final pH of the fermentation broth as well as the identification and concentrations of SCFA depended on the type of OLI and probiotic used.

CONCLUSION

The OS mucilage is an unconventional fiber source and can be used to produce non-digestible OLI as functional compounds. This knowledge will be useful for proposing new sustainable ways of processing cacti crops for food and industrial purposes. © 2018 Society of Chemical Industry.

Probiotic Lactobacillus spp. act Against Helicobacter pylori-induced Inflammation

The bacterial species, Helicobacter pylori, is associated with several gastrointestinal diseases, and poses serious health threats owing to its resistance to antibiotics. Lactobacillus spp., on the other hand, possess probiotic activities that have beneficial effects in humans. However, the mechanisms by which Lactobacillus spp. harbor favorable functions and act against H. pylori infection remain to be explored. The aim of this study was to investigate the ability of bacterial strains, Lactobacillus rhamnosus and Lactobacillus acidophilus, termed GMNL-74 and GMNL-185, respectively, to inhibit H. pylori growth and inflammation. Our results showed that GMNL-74 and GMNL-185 possess potent antimicrobial activity against multidrug resistant (MDR)-H. pylori. In addition, an in vitro cell-based model revealed that the inhibition of H. pylori adhesion and invasion of gastric epithelial cells and interleukin-8 production were significantly decreased by treatment with both the Lactobacillus strains. In vivo studies demonstrated that colonization of H. pylori and induced inflammation in the mouse stomach were also alleviated by these Lactobacillus strains. Furthermore, the abundance of beneficial gut bacteria, including Bifidobacterium spp. and Akkermansia muciniphilia, were significantly increased in H. pylori-infected mice treated with GMNL-74 and GMNL-185. These results demonstrate that Lactobacillus spp. ameliorate H. pylori-induced inflammation and supports beneficial gut specific bacteria that act against H. pylori infection.

Effects of nanobubble water on the growth ofLactobacillus acidophilus1028 and its lactic acid production

Nanobubbles (NBs) in the culture medium may offer a new way of accelerating bacterial growth in the lag and logarithmic phases.

POSTOPERATIVE CHANGES IN INTESTINAL MICROBIOTA AND USE OF PROBIOTICS IN ROUX-EN-Y GASTRIC BYPASS AND SLEEVE VERTICAL GASTRECTOMY: AN INTEGRATIVE REVIEW

Introduction:

Studies suggest that weight loss induced by bariatric surgery and the remission of some comorbidities may be related to changes in the microbiota profile of individuals undergoing this procedure. In addition, there is evidence that manipulation of the intestinal microbiota may prove to be a therapeutic approach against obesity and metabolic diseases.

Objective:

To verify the changes that occur in the intestinal microbiota of patients undergoing bariatric surgery, and the impact of the usage of probiotics in this population.

Methods:

Articles published between 2007 and 2017 were searched in Medline, Lilacs and Pubmed with the headings: bariatric surgery, microbiota, microbiome and probiotics, in Portuguese, English and Spanish. Of the 166 articles found, only those studies in adults subjected to either Roux-en-Y gastric bypass or sleeve vertical gastrectomy published in original articles were enrolled. In the end, five studies on the change of intestinal microbiota composition, four on the indirect effects of those changes and three on the probiotics administration on this population were enrolled and characterized.

Conclusion:

Bariatric surgery provides changes in intestinal microbiota, with a relative increase of the Bacteroidetes and Proteobacteria phyla and reduction of Firmicutes. This is possibly due to changes in the gastro-intestinal flux, coupled with a reduction in acidity, in addition to changes in eating habits. The usage of probiotics seems to reduce the gastro-intestinal symptoms in the post-surgery, favor the increase of vitamin B12 synthesis, as well as potentiate weight loss.