Adhesion Of Probiotics Research Articles

Ex-vivo investigation of probiotic bacterial adhesion to the intestinal mucus

Recent research has promoted considerable interest in the potential health benefits of the new generation of probiotics. Despite the abundance of probiotic supplements, their adhesion and thereby colonization in the intestinal tract of the host, a determining factor of probiotic efficacy, remains questionable. Indeed, the gastrointestinal tract, a multi-component and complex system, obscures the comprehensive understanding of the probiotic adhesion mechanism. This study aimed to investigate the adhesion capacity of probiotic bacteria using two ex-vivo approaches that were specifically developed to investigate the bacteria-mucus agglomeration and the viable adhesion to intestinal mucus. Five probiotic bacterial strains including Escherichia coli, Lactiplantibacillus plantarum, Faecalibacterium duncaniae, Bifidobacterium longum, and Bifidobacterium longum str. infantis were selected for the investigation. In that context, higher adhesion to mucus was demonstrated by E. coli, L. plantarum, and B. infantis, emphasizing strain-specific differences. While total agglomeration capacity ranged from 8 % to 82 %, actual viable adhesion to mucus remained rather low (0.6 %–2.9 %). SEM images revealed that morphological characteristics, chain and/or cluster forming ability, as well as the presence of surface exopolysaccharides, might have an impact on bacterial adhesion. This study contributes knowledge on probiotic adhesion as well as simple and effective ex-vivo approaches to investigate the bacterial adhesion to the intestinal mucus, which is prerequisite for further colonization in the gut of the host.

Study of Lactobacillus plantarum coated with Tremella polysaccharides to improve its intestinal adhesion.

The adhesion of probiotics to the intestine is crucial for their probiotic function. In previous studies, Tremella polysaccharides (TPS) (with sodium casein) have shown the potential to encapsulate probiotics and protect them in a simulated gastrointestinal tract. This study explored the effect of TPS (with sodium casein) on the adhesion of probiotics. Lactobacillus plantarum was coated with TPS and sodium casein in different proportions, and was freeze-dried. The rheological properties of the mixture of probiotics powder and mucin solution were determined by static and dynamic rheological analysis. Aqueous solutions of probiotic powder and mucin mixture exhibited pseudoplastic fluid rheological properties. The higher the proportion of TPS content, the higher the apparent viscosity and yield stress. The mixed bacterial powder and mucin fluid displayed thixotropy and was in accordance with the Herschel-Bulkley model. The TPS increased the bio-adhesive force of the probiotic powder and mucin. When using TPS as the only carbon source, the adhesion of L. plantarum to Caco-2 cells increased by 228% in comparison with glucose in vitro. Twelve adhesive proteins were also detected in the whole-cell proteome of L. plantarum. Among them, ten adhesive proteins occurred abundantly when grown with TPS as a carbon source. Tremella polysaccharides therefore possess probiotic properties and can promote the intestinal adhesion of L. plantarum. © 2024 Society of Chemical Industry.

Bacterial community of Parvocalanus crassirostris nauplii and the potential of nauplii as a vector for early probiotic supply to fish larvae

AbstractObjectiveThe copepod Parvocalanus crassirostris has recently increased its use as live food in marine fish hatcheries.MethodsTo investigate the bacterial community of P. crassirostris nauplii and explore the potential use of nauplii as a vector for probiotics, adult copepods were reared with or without a probiotic consortium (Bacillus spp. and Lactobacillus spp.). Nauplii from both treatments were either enriched with probiotics or not, resulting in four treatments: control rearing and nonenriched, control rearing and probiotic enriched, probiotic rearing and nonenriched, and probiotic rearing probiotic enriched. A next‐generation sequencing analysis of the 16S ribosomal RNA gene was performed.ResultThe bacterial community of nauplii without probiotics was dominated by the phyla Proteobacteria (mean ± standard deviation = 51.5 ± 8.0%) and Bacteroidetes (27.6 ± 6.7%); from these phyla, the most abundant orders were Rhodobacterales (21.8 ± 2.0%), Flavobacteriales (13.5 ± 9.4%), Chitinophagales (9.7 ± 1.8%), Alteromonadales (9.5 ± 4.0%), and Burkholderiales (3.8 ± 0.8%). Opportunistic pathogenic bacterial genera, such as Vibrio spp. and Pseudomonas spp., were detected at very low relative abundances (<1.2%), indicating that P. crassirostris nauplii could be considered a safe microbiological live feed. Furthermore, P. crassirostris nauplii were a good vector for probiotics delivery, as the adhesion of probiotics on the copepod exoskeleton was successful. Bacillus spp. abundance was 5–6× greater than the abundance of Lactobacillus spp. in P. crassirostris nauplii. The highest mean values of probiotics relative abundance (Bacillus spp. 41 ± 6.0%, Lactobacillus spp. 6.0 ± 3.0%) were observed in nauplii that were reared with probiotics and also enriched with probiotics.ConclusionParvocalanus crassirostris nauplii stages I–II appear to be good vectors to provide probiotics to first‐feeding fish larvae.

Microfluidic fabrication of encapsulated probiotic microspheres using cysteine-modified chitosan with dual functions of bacterial adhesion and intestinal mucosal adhesion

Compared with previous encapsulation methods, the emerging microfluidic approach has the potential of preparing monodispersed particles with considerable advantages, such as controlled size and morphology, stable yield, and enhanced repeatability. In addition to introducing probiotics to the intestine with high-viability, designing a novel carrier matrix to improve the mucoadhesion of probiotics in the intestine is imperative. Thus, in this study, the thiol groups of cysteine were grafted to chitosan to form disulfide bonds with the cysteine residues on the bacterial surface and mucus to achieve the dual function of probiotic adhesion and mucoadhesion. Upon examination, the adhesion rate of Bifidobacterium bifidum FL-276.1 (FL-276.1) to thiolated chitosan film increased by 1.33 times compared with non-modified chitosan film. Thiolated chitosan microspheres prepared by microfluidic method assisted by a crosslinking unit with a crosslinker of genipin had a uniform size distribution, high loading efficiency (80%) to FL-276.1, and improved resistance to simulated gastrointestinal digestion with a survival rate of FL-276.1 up to 92%. Moreover, the results of mucoadhesion test of thiolated chitosan microspheres demonstrated that the amount of thiolated chitosan microspheres adhered to the HT-29 cells was 2.27 times higher than that of chitosan microspheres. The monodispersed cysteine modified chitosan microspheres with dual adhesion function prepared by microfluidic technology has the potential to enhance the viability and function of probiotics after gastrointestinal digestion and intestinal adhesion.

Role of Surface Coverage of Sessile Probiotics in Their Interplay with Pathogen Bacteria Investigated by Digital Holographic Microscopy.

The adhesion of probiotics plays an important role in the gastrointestinal tract. Understanding the effect of the coverage of colonized probiotics on enteric pathogens is critical for the design of effective probiotic therapies. In the present work, we have investigated the adaptive behaviors of the intestinal pathogenic bacteria Enterobacter sakazakii (ES) near the surfaces coated with a probiotic─Lactobacillus rhamnosus GG (LGG) as a function of surface coverage ratio (CRLGG) by using a home-setup digital holographic microscopy. It shows that ES cells can adaptively sense LGG within a distance of 4.2 μm, even at CRLGG values as low as 0.05%. The growth inhibition of ES cells slightly varies with CRLGG, but the near-surface acceleration and accumulation of ES cells have much dependence on CRLGG. As CRLGG increases from 0.05 to 24.6%, the percentage of actively swimming ES, the motion bias, the acceleration, and the interplay duration do not linearly vary with CRLGG. Instead, each of them shows an extreme at CRLGG of 13.4%, corresponding to the chemotaxis behaviors of ES cells induced by diffusing stimuli (organic acids, bacteriocins, etc.) released from LGG, which showed an extreme concentration gradient at CRLGG = 13.4% by simulations. Our study clearly demonstrates that surface coverage of sessile probiotics profoundly influences their interplay with pathogen bacteria, which should be taken into account in designing probiotic therapies.

Effect of sturgeon protein in promoting the adhesion of Lactobacillus plantarum and Lactobacillus rhamnosus

Dietary protein could serve as primary nitrogen source for intestinal flora to enhance the intestinal environment by influencing probiotic adhesion. Our work aims to demonstrate a framework for probiotic activity guided isolation of potential effective fractions from the sturgeon protein. We confirmed the isolated fractions of sturgeon protein as having probiotic adhesion activity against Lactobacillus plantarum 45 (LP45) and Lactobacillus rhamnosus GG (LGG). Three protein fractions (0%, 40%, and 60% NaCl elution fractions) were obtained through anion exchange resin column. The molecular weights of the three fractions were identified by polyacrylamide gel electrophoresis in the ranges of 20.1–66.4 kDa (Fr1), 14.3–44.3 kDa (Fr2) and 14.3–97.2 kDa (Fr3), respectively. A detailed study was performed using an in vitro adhesion model to obtain the bioactive protein. In this model, probiotics were incubated on isolated intestinal segments of mice, and the adhesion effect of probiotics was evaluated through polysaccharide analysis, biofilm quantification, viable count measurement and electron microscopy. Notably, Fr2 was identified as the most effective fractions, significantly increasing the intestinal adhesion rates of LP45 and LGG by 144.8% and 53.7%, respectively. Ultimately, the primary structure of the protein 14.3 kDa in Fr2 was identified by mass spectrometry. Partial peptide amino acid sequences of the protein were confirmed to be W-W-Y-C-F (m/z = 804), K-N-H-D-I/L-Q-A-D-D-I/L-T-C (m/z = 1510) and Q-M-V-H-K-I/L-E-D-E-E-I/L-C-T-S-A-D-K-D (m/z = 2300). In conclusion, we found evidence that purified fractions of sturgeon protein facilitates the adhesion of intestinal probiotics and can be used as an active protein beneficial for intestinal health.

Homologous genes shared between probiotics and pathogens affect the adhesion of probiotics and exclusion of pathogens in the gut mucus of shrimp.

Clarifying mechanisms underlying the selective adhesion of probiotics and competitive exclusion of pathogens in the intestine is a central theme for shrimp health. Under experimental manipulation of probiotic strain (i.e., Lactiplantibacillus plantarum HC-2) adhesion to the shrimp mucus, this study tested the core hypothesis that homologous genes shared between probiotic and pathogen would affect the adhesion of probiotics and exclusion of pathogens by regulating the membrane proteins of probiotics. Results indicated that the reduction of FtsH protease activity, which significantly correlated with the increase of membrane proteins, could increase the adhesion ability of L. plantarum HC-2 to the mucus. These membrane proteins mainly involved in transport (glycine betaine/carnitine/choline ABC transporter choS, ABC transporter, ATP synthase subunit a atpB, amino acid permease) and regulation of cellular processes (histidine kinase). The genes encoding the membrane proteins were significantly (p < 0.05) up-regulated except those encoding ABC transporters and histidine kinases in L. plantarum HC-2 when co-cultured with Vibrio parahaemolyticus E1, indicating that these genes could help L. plantarum HC-2 to competitively exclude pathogens. Moreover, an arsenal of genes predicted to be involved in carbohydrate metabolism and bacteria-host interactions were identified in L. plantarum HC-2, indicating a clear strain adaption to host's gastrointestinal tract. This study advances our mechanistic understanding of the selective adhesion of probiotics and competitive exclusion of pathogens in the intestine, and has important implications for screening and applying new probiotics for maintaining gut stability and host health.

Crypt-like patterned electrospun nanofibrous membrane and probiotics promote intestinal epithelium models close to tissues.

In vitro intestinal epithelium models have drawn great attention to investigating intestinal biology in recent years. However, the difficulty to maintain the normal physiological status of primary intestinal epithelium in vitro limits the applications. Here, we designed patterned electrospun polylactic acid (PLA) nanofibrous membranes with crypt-like topography and mimic ECM fibrous network to support crypt culture and construct in vitro intestinal epithelium models. The patterned electrospun PLA nanofibrous membranes modified with Matrigels at 0°C showed high biocompatibility and promoted cell growth and proliferation. The constructed duodenum epithelium models and colon epithelium models on the patterned electrospun PLA nanofibrous membranes expressed the typical differentiation markers of intestinal epithelia and the gene expression levels were close to the original tissues, especially with the help of probiotics. The constructed intestinal epithelium models could be used to assess probiotic adhesion and colonization, which were verified to show significant differences with the Caco-2 cell models due to the different cell types. These findings provide new insights and a better understanding of the roles of biophysical, biochemical, and biological signals in the construction of in vitro intestinal epithelium models as well as the potential applications of these models in the study of host-gut microbes interactions. KEY POINTS: • Patterned electrospun scaffold has crypt-like topography and ECM nanofibrous network. • Matrigels at 0°C modify scaffolds more effectively than at 37°C. • Synergy of biomimic scaffold and probiotics makes in vitro model close to tissue.

Adjunctive role of Q10 with Ligilactobacillus salivarius, and Lactiplantibacillus plantarum probiotic Bacteria on the HEp-2 cells viability and adhesion of Streptococcus mutans.

Various studies have indicated the application of Coenzyme Q10 and probiotic bacteria such as Ligilactobacillus salivarius (L. salivarius) and Lactiplantibacillus plantarum (L. plantarum) in combating periodontal disease. Considering the positive effect of these two on oral health, and the destructive effect of S. mutans, in this study, we investigate the outcomes of the administration of probiotics and Q10 on infected HEp-2 cell viability and S. mutans adhesion in different settings. A 3-week-old human epidermoid laryngeal (HEp-2) cell line was cultured and exposed to two different probiotics and 3 different doses of Q10 doses. Samples were contaminated by S. mutans immediately (therapeutic setting) and after 3 hours (preventive setting). Eventually, the viability of HEp-2 cells was investigated by MTT. Also, the number of adhered S. mutans was explored by direct and indirect adhesion assays. L. plantarum and L. salivarius protect epithelial cells against S. mutans in both therapeutic and preventive settings, albeit not fully. In contrast, Q10 completely preserves the viability of infected Her HEp-2 cells at all concentrations. The effects of the coexistence of Q10 and probiotics were not quite equal, among which L. salivarius and 5 μg of Q10 form the best results. The microscopic adherence assay of S. mutans revealed that samples containing Q10 had significantly lower adhesion of probiotics and S. mutans to HEp-2 cells. Similarly, plates containing L. salivarius with 5μg or L. plantarum with 1μg Q10 or sole presence of L. salivarius had the lowest S. mutans adherence among others. Also, L. salivarius with 5μg Q10 had one of the highest probiotic adherences. In conclusion, co-administration of Q10 and probiotics especially in presence of L. salivarius with 5μg Q10 could have remarkable effects on HEp-2 cell viability, S. mutans, and probiotic adherence. Nevertheless, our study, for the first time, showed that Q10 might have an anti-bacterial activity by suppressing the adhesion of tested bacteria to HEp-2 cells. This hypothesis, if correct, suggests that due to their different mechanisms, co-prescription of Q10 and probiotics may lead to better clinical responses, especially in the mentiond dose.

Construction of Probiotic Double-Layered Multinucleated Microcapsules Based on Sulfhydryl-Modified Carboxymethyl Cellulose Sodium for Increased Intestinal Adhesion of Probiotics and Therapy for Intestinal Inflammation Induced by Escherichia coli O157:H7.

The decreased number of viable bacteria and the ability of Bifidobacterium to adhere to and colonize the gut in the gastrointestinal environment greatly limit their efficacy. To solve this problem, thiolated carboxymethyl cellulose sodium (CMC) probiotic double-layered multinucleated microcapsules with Bifidobacterium adolescentis FS2-3 in the inner layer and Bacillus subtilis SN15-2 embedded in the outer layers were designed. First, the viable counts and release rates of microcapsules were examined by in vitro simulated digestion assays, and it was found that microcapsules were better protected from gastrointestinal digestion than the controls. Compared with free Bifidobacterium strains, double-layered multinucleated microcapsules have higher viable bacterial survival rates and storage stability. Second, through in vitro rheology, tensile tests, isotherm titration calorimetry, and adhesion tests, it was observed that thiolated CMC could enhance the strong interaction of Bifidobacterium with intestinal mucus and significantly promote the proliferation and growth of probiotics. Finally, double-layered multinucleated microcapsules containing B. adolescentis FS2-3 and B. subtilis SN15-2 modified with sulfhydryl-modified CMC were studied in the intestine. Alleviation of Escherichia coli O157:H7 induced intestinal inflammation. The results showed that microencapsulation could significantly increase the colon content of Bifidobacterium, relieve intestinal inflammation symptoms in mice with bacterial enteritis, and repair the intestinal microbiota disorder caused by inflammation. The probiotic double-layered multinucleated microcapsules prepared in this study can improve the survival rate of probiotics and promote proliferation, adhesion, and colonization of probiotics.

Development of novel probiotics for the intestinal diseases associated with mucin alterations by adaptive laboratory evolution

Several lactic acid bacterial (LAB) strains have probiotic properties. A crucial requirement for probiotics to benefit the host’s health is their ability to adhere to the intestinal lining enriched with glycosylated mucins. Many intestinal diseases display marked changes in mucin glycosylation such as reduced sialylation and fucosylation. Such alterations have been shown to allow for the lesser adhesion of the probiotic bacteria in vitro. Although probiotics are often used in intestinal diseases, this phenomenon might reduce their in vivo intestinal adhesion, which could be a reason for the ineffectiveness of some probiotics in such conditions as reported in a few studies. Adaptive laboratory evolution (ALE) offers an intuitive way of improving bacterial properties without performing deliberate genetic modifications. In this paper, it is hypothesized that probiotic strains with enhanced adhesion to the mucin altered in intestinal diseases would be better candidates to alleviate the symptoms of these diseases, and such strains can be created through ALE. This hypothesis is supported by a few earlier studies showing the ability of certain other bacteria to mutate themselves to enhance their adhesion to biotic and abiotic environments. The steps involved in testing the hypothesis would be improving the in vitro adhesion of lactobacilli to the intestinal mucus obtained from patients with intestinal diseases by daily adhesion and passaging of the adherent bacteria for several weeks. The improved strains can be subjected to animal studies and human clinical trials in the second part. Since some commensals make short-chain fatty acids from dietary fiber, which stimulate mucin production by the intestinal cells, the clinical trials can be performed under a dietary regime. Apart from providing novel probiotic candidates, such a study can also reveal yet the novel mechanism of adhesion of probiotics to the intestinal environment.

Impact of a Purified Blueberry Extract on In Vitro Probiotic Mucin-Adhesion and Its Effect on Probiotic/Intestinal Pathogen Systems.

Several arguments have been made to substantiate the need for natural antimicrobials for the food industry. With blueberry extracts, the most compelling are both their healthy connotation and the possibility of obtaining a multipurpose solution that can be an antioxidant, colorant, and antimicrobial. From an antimicrobial perspective, as blueberry/anthocyanin-rich extracts have been associated with a capacity to inhibit harmful bacteria while causing little to no inhibition on potential probiotic microorganisms, the study of potential benefits that come from synergies between the extract and probiotics may be of particular interest. Therefore, the present work aimed to evaluate the effect of an anthocyanin-rich extract on the adhesion of five different probiotics as well as their effect on the probiotics’ capacity to compete with or block pathogen adhesion to a mucin/BSA-treated surface. The results showed that, despite some loss of probiotic adhesion, the combined presence of extract and probiotic is more effective in reducing the overall amount of adhered viable pathogen cells than the PROBIOTIC alone, regardless of the probiotic/pathogen system considered. Furthermore, in some instances, the combination of the extract with Bifidobacterium animalis Bo allowed for almost complete inhibition of pathogen adhesion.

Polysaccharide ORP-1 isolated from Oudemansiella raphanipes ameliorates age-associated intestinal epithelial barrier dysfunction in Caco-2 cells monolayer

Age-associated increase in intestinal permeability is known to relate with gut microbiota dysbiosis and loss of epithelial tissue integrity. To improve healthy aging and prevent age-associated chronic disabilities, the protective potential of polysaccharides from Oudemansiella raphanipes (ORP-1) against age-associated intestinal epithelial barrier dysfunction in d-galactose-induced Caco-2 cells monolayer was investigated. In-vitro results demonstrated that ORP-1 can restore a healthy gut microbial population to handle age-related gut microbiota dysbiosis mainly by facilitating the proliferation and adhesion of probiotics Lactobacillus acidophilus (L. acidophilus) and Bifidobacterium bifidum (B. bifidum) to compete with intestinal pathogenic Escherichia coli (E. coli) for ecological niches and nutrition. Meanwhile, ORP-1 strengthened the intestinal structural integrity primarily by abolishing the aggravation of apoptosis and the age-associated alterations of tight junction (TJ) proteins expression in intestine. These findings highlighted that ORP-1 could be a potential functional food component with preventive utility against age-associated intestinal barrier injury.

Probiotic Adhesion to Skin Keratinocytes and Underlying Mechanisms.

Simple SummaryThe use of probiotics to ameliorate skin conditions has been suggested. This is based in the fact that they compete with pathogenic bacteria for adhesion sites, thereby displacing unwanted microorganisms. Lacticaseibacillus rhamnosus was able to adhere effectively to keratinocytes decreasing the number of adherent pathogenic bacteria. In the presence of pathogens all tested probiotics decreased invasion by S. aureus, one of the most relevant skin pathogens. Ex vivo models also showed wound healing capacity of L. rhamnosus with a concomitant decrease in the viable numbers of S. aureus, suggesting it is a good candidate as a co-adjuvant in the treatment of skin infections by this pathogen.The effects of probiotics on the skin are not yet well understood. Their topical application and benefits derived thereafter have recently been investigated. Improvements in different skin disorders such as atopic dermatitis, acne, eczema, and psoriasis after their use have, however, been reported. One of the mechanisms through which such benefits are documented is by inhibiting colonization by skin pathogens. Bacterial adhesion is the first step for colonization to occur; therefore, to avoid pathogenic colonization, inhibiting adhesion is crucial. In this study, invasion and adhesion studies have been carried out using keratinocytes. These showed that Escherichia coli is not able to invade skin keratinocytes, but adhered to them. Lacticaseibacillus rhamnosus and Propioniferax innocua decreased the viable counts of the three pathogens under study. L. rhamnosus significantly inhibited S. aureus adhesion. P. innocua did not inhibit pathogenic bacteria adhesion, but when added simultaneously with S. aureus (competition assay) a significant adhesion reduction (1.12 ± 0.14 log10CFU/mL) was observed. Probiotic bacteria seem to use carbohydrates to adhere to the keratinocytes, while S. aureus uses proteins. Lacticaseibacillus rhamnosus showed promising results in pathogen inhibition in both in vitro and ex vivo experiments and can potentially be used as a reinforcement of conventional therapies for skin dysbiosis.

Xiong Fu Powder Regulates the Intestinal Microenvironment to Protect Bones Against Destruction in Collagen-Induced Arthritis Rat Models

BackgroundChanges in the intestinal microenvironment affected bone destruction in rheumatoid arthritis (RA), and spleen deficiency (SD) was closely related to the intestinal microenvironment. In this study, we aimed to explore the aggravation of SD on collagen-induced arthritis (CIA) and the bone protection of compound Xiong Fu powder (XFP) on CIA with SD (SD-CIA) based on the intestinal microenvironment.MethodAn SD-CIA rat model was established using Rheum officinale Baill. decoction combined with CIA and then treated with XFP. The aggravating action of SD on CIA rats and the efficacy of XFP were evaluated using AI scores, H&E staining of the joint, and level of serum anti–collagen type II antibody (Col II Ab). Bone destruction was assessed by micro-CT and TRACP staining. In addition, flow cytometry, qRT-PCR, and ELISA were used to evaluate gut mucosal immunity. Moreover, metagenomic sequencing was used to determine the distribution and function of the gut microbiota.ResultsCompared with that in CIA rats, bone destruction in SD-CIA rats was aggravated, as manifested by increased AI scores, more severe joint pathological changes and radiological damage, and increased number of osteoclasts (OCs) in the ankle joint. Meanwhile, the proportion of Tregs/Th17 cells was biased toward Th17 cells in Peyer’s patches. Furthermore, the gene levels of TNF-α, IL-1β, IL-6, and IL-17 were increased. In contrast, the expression of IL-10 and sIgA was decreased in the jejunum and ileum. XFP treatment improved bone damage and intestinal mucosal immune disorders compared with the SD-CIA group. In addition, the distribution and function of the gut microbiota were altered in the SD-CIA group. After XFP treatment, the community and function of the gut microbiota were regulated, manifested as increased abundance of several Lactobacillus species, such as L. acidophilus, which regulates the intestinal Tregs/Th17 cells and quorum sensing pathways, followed by promoting probiotic adhesion to the intestines.ConclusionSD can aggravate bone destruction in CIA rats. Compound XFP may attenuate bone destruction in SD-CIA rats by regulating the intestinal microenvironment. One of the mechanisms is the cross-talk between sIgA secretion regulated by intestinal mucosal Tregs and Th17 cells and adhesion of Lactobacillus mediated by quorum sensing.

Bioprophylactic potential of novel human colostrum probiotics via apoptotic induction of colon cancer cells and cell immune activation

The potential and modes of action of novel human colostrum probiotics were investigated with the aim of studying their application as an alternative in the bioprophylactic and biotherapy of colon cancer. A total of 218 isolates of Gram-positive rod and cocci bacteria obtained from the colostrum of 50 healthy lactating females were collected. Beneficial probiotic criteria from these isolates, which included growth inhibition against seven foodborne pathogens (Helicobacter pylori, Escherichia coli, Salmonella Enteritidis, Salmonella Typhimurium, Staphylococcus aureus, Bacillus cereus and Listeria monocytogenes), no blood haemolysis and tolerance to acid and bile salt conditions, resulted in only eight probiotic bacteria successfully inhibiting the proliferation of colon cancer cells at rates of 32.47–61.21%. Two probiotic bacteria with higher anticancer efficacy (Streptococcus salivarius CP163 and S. salivarius CP208) were identified using 16S rRNA sequences. High rates of cell surface hydrophobicity, autoaggregation and coaggregation were obtained from both probiotics. The probiotic mode of action involved synergic probiotic adhesion to colon cancer cells that triggered SCFA bioproduction. Apoptotic induction of colon cancer cell death through caspase-2 activity, DNA fragmentation and morphological change as assessed by AO/PI staining were also observed. Immune stimulation by S. salivarius CP163 and S. salivarius CP208 resulted in B and T-cell lymphocyte activation. This study suggests that these novel human colostrum probiotics could be applied as a functional food to facilitate a bioprophylactic strategy in colon cancer.

Effects of Ilisha elongata proteins on proliferation and adhesion of Lactobacillus plantarum

The effects of aquatic proteins on the proliferation and adhesion of intestinal probiotic bacteria were investigated by in vitro fermentation and mouse in vitrointestinal tissue models. Compared with the control group, the Illisha elongata protein reduced the growth time of Lactobacillus plantarum (LP45) by 34.25% and increased the total number of colonies by 6.61%. The Ilisha elongata salt-solubale protein performed better than water-soluble protein in vitro proliferation of LP45. Ilisha elongata salt-soluble protein significantly increased the number of viable bacteria adhering to intestinal, and caused changes in the amount of polysaccharides, proteins and biofilms in the intestinal tissue model. These results indicate that the Ilisha elongata protein is beneficial to the proliferation and adhesion of probiotics in the intestinal, and can be used as an active protein beneficial to intestinal health.

Effect of α-linolenic acid (ALA) on proliferation of probiotics and its adhesion to colonic epithelial cells

The effects of α-linolenic acid (ALA) on the proliferation and adhesion of probiotics would be investigated in the present study. Effects of ALA on intestinal flora were studied by animal fecal anaerobic fermentation system in vitro, which were analyzed by high-throughput sequencing. Results showed that treatment with ALA could promote the proliferation of probiotics Lactobacillus and Bifidobacterium, and inhibit the growth of harmful bacteria Enterococcus and E. coli. ALA restored the abnormal intestinal flora caused by high-fat diet, which was beneficial to the improvement of intestinal flora structure. In addition, adhesive characteristics of probiotics to epithelial colon cells NCM460 were detected by plate counting and Gram staining, which indicated that ALA promoted adhesion of probiotics to colonic cells. In conclusion, ALA could promote the proliferation and adhesion of intestinal probiotics, which provides a basis for ALA to exert the healthy activities of intestinal probiotics.

Effects of Ilisha elongata protein, soy protein and whey protein on growth characteristics and adhesion of probiotics

The effects of different food source proteins on the growth characteristics and intestinal adhesion of Lactobacillus plantarum 45 (LP45) were investigated by adding Ilisha elongata protein, soy protein and whey protein to the probiotic bacteria in vitro and using a probiotic adhesion model based on mouse intestinal tissues. Ilisha elongata protein and soy protein significantly reduced the growth time of LP45 and increased the total number of colonies fermented by LP45; whey protein only reduced the growth time of LP45; the effect of the three food source proteins on the acid production capacity of LP45 was small. These showed that the three food-derived proteins promoted the proliferation and adhesion of probiotics in the intestine, which were beneficial to the active role of intestinal probiotics and improved the intestinal microenvironment.

The adhesion of the gut microbiota to insoluble dietary fiber from soy hulls promoted the proliferation of probiotics in vitro

Soy hull insoluble dietary fiber (SHIDF) extracted from soybean water-soluble polysaccharides enzymatically is a good carbon source for the growth of gut microbiota. Genomics, co-precipitation and proteomics analyses were used to investigate adhesion behavior of the gut microbiota toward SHIDF in vitro. After gut microbiota fermentation, the content of total and reducing sugars decreased with increasing fermentation time, but the content of NH3–N first increased and then decreased, and gas was produced mainly during 8–16 h. The structure and abundance of the gut microbiota were regulated after fermentation. Proliferation of beneficial bacteria increased, particularly Lactobacillus and Bifidobacterium. The adhesion of Lactobacillus plantarum and Bifidobacterium longum to SHIDF increased gradually with increasing adhesion time. The adhesion of two probiotics to IDF first increased and then decreased with increasing bacterial age (6, 12, 24, and 36 h). SDS, EDTA, bile salts, trypsin and proteinase K in the adhesion environment affected probiotic adhesion to SHIDF to a certain extent. Lactobacillus plantarum and Bifidobacterium longum showed significant differences in adhesion membrane proteins after SHIDF treatment. The 30S ribosomal protein S21 and GAPDH (glyceraldehyde 3-phosphate dehydrogenase), a surface protein involved in intestinal adhesion, were found to be significantly upregulated through label free proteomic analysis.