Interaction of Companilactobacillus crustorum MN047-derived bacteriocins with gut microbiota

Development of plantaricin RX-8 loaded pectin/4-carboxyphenylboric acid/carboxymethyl chitosan hydrogel microbead: A potential targeted oral delivery system

Bacteriocin can effectively improve the gut inflammation for their superior antibacterial activity. However, its inherent attributes, such as easily degraded and off-target effect in the gastrointestinal environment, make bacteriocins' efficient oral delivery a great challenge. Herein, a pectin/4-carboxyphenylboric acid/carboxymethyl chitosan (PEC/CPBA/CMCS) hydrogel microbead targeted oral delivery system was innovatively developed for the plantaricin RX-8 protective delivery, precisely targeted inflammatory microenvironment (IME) and sustained released plantaricin RX-8 by pH/ROS dual stimulation response. The hydrogel microbeads showed regular in shape and size, and exhibited high affinity for sialic acid of tumor cells. Subsequently, hydrogel microbeads exhibited the protective effect in gastrointestinal tract to avoid plantaricin RX-8 leakage, whereas in simulated normal environment and simulated IME showed better swelling and sustain release behaviors. Notably, the plantaricin RX-8 retains antibacterial activity in the simulated environments. Importantly, hydrogel microbeads showed no toxicity and inhibited tumor cell proliferation, which was ascribed to the sustained release of plantaricin RX-8 under ROS-sensitive IME, as validated by in vivo fluorescence imaging. Microbead not only demonstrated biodistribution in high potency, but also exhibited remarkable anti-inflammatory properties in alleviating colitis in vivo. The present study highlights the promising application of hydrogel carriers for improved oral delivery approach of bacteriocin bioavailability.

L-Theanine Mitigates Acute Alcoholic Intestinal Injury by Activating the HIF-1 Signaling Pathway to Regulate the TLR4/NF-κB/HIF-1α Axis in Mice

BACKGROUND/OBJECTIVES

Acute alcohol consumption can cause intestinal dysfunction, whereas L-theanine (LTA) has shown the potential to support intestinal health. We explored L-theanine's ability to protect against acute alcohol-induced injury.

METHODS

Male C57BL/6 mice were administered LTA for 28 d and then underwent acute alcohol intestinal injury modeling for 8 days.

RESULTS

The results revealed that LTA ameliorated alcohol-induced pathological damage in the duodenum and gut permeability, improved secretory immunoglobulin A (SIgA) content, and reduced oxidative stress, inflammatory markers, and serum lipopolysaccharide (LPS) content in mice. Furthermore, LTA restored the composition of the intestinal flora, increasing the abundance of Alloprevotella, Candidatus_Saccharimonas, Muribaculum, and Prevotellaceae_UCG-001. Additionally, LTA increased beneficial metabolites, such as oxyglutaric acid and L-ascorbic acid, in the HIF-1 pathway within the enrichment pathway. Further investigation into the HIF-1 signaling pathway identified up-regulation of claudin-1, HIF-1α, occludin, and ZO-1, and down-regulation of TLR4, PHD2, p65 NF-κB, TNF-α, and IFN-γ mRNA and protein levels.

CONCLUSIONS

These results suggest that LTA may enhance the intestinal barrier by activating the HIF-1 signaling pathway to regulate the TLR4/NF-κB/HIF-1α axis, thereby reducing acute alcoholic intestinal injury.

Probiotic Bacillus pumilus LV149 enhances gut repair, modulates microbiota, and alters transcriptome in DSS-induced colitis mice

Purpose

Gut microbiota dysbiosis significantly impacts ulcerative colitis (UC) progression and exacerbation. Probiotics show promise in UC management. This study evaluated the effects of different doses of Bacillus pumilus LV149, an aquatic-derived probiotic, on gut injury repair in male C57BL/6 mice with dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) and investigated the underlying mechanisms.

Methods

UC was induced by allowing mice free access to a 3% DSS solution for 7 days, with concurrent daily oral gavage of either a low (LV149-L, 1 × 108 CFU/day/mouse) or high (LV149-H, 1 × 109 CFU/day/mouse) dose of LV149. The effects were assessed through physiological parameters, intestinal barrier integrity, inflammation, gut microbiota composition, and transcriptomic changes.

Results

LV149 significantly improved pathological symptoms, including weight loss and disease activity index (DAI), and reduced colon shortening in a dose-dependent manner and inflammatory damage. The intervention also restored gut barrier function by upregulating mucins, goblet cell counts, and tight junction proteins (ZO-1, occludin, and claudin-1) in colonic tissue, along with reducing serum lipopolysaccharide (LPS) levels. Notably, only the LV149-H significantly decreased the expression of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6, while both doses increased the expression of the anti-inflammatory cytokine IL-10 in a dose-dependent in colonic tissue. LV149 further modulated the gut microbiota, increasing beneficial bacteria and reducing pathogenic populations. Transcriptomic analysis indicated that LV149-L may exert gut repair effects via the IL-17 signaling pathway, whereas LV149-H appears to act through the JAK-STAT signaling pathway.

Conclusion

This study demonstrated that LV149, particularly at a higher dose, effectively mitigated DSS-induced colonic injury by modulating gut microbiota, enhancing gut barrier integrity, and reducing inflammation. The dose-dependent effects underscored LV149-H's potential as a therapeutic agent for UC due to its stronger anti-inflammatory properties and gut-protective effects.

The Bacteriocins Produced by Lactic Acid Bacteria and the Promising Applications in Promoting Gastrointestinal Health

Bacteriocins produced by lactic acid bacteria (LAB) are promising bioactive peptides. Intriguingly, bacteriocins have health benefits to the host and may be applied safely in the food industry as bio-preservatives or as therapeutic interventions preventing intestinal diseases. In recent years, finding a safe alternative approach to conventional treatments to promote gut health is a scientific hotspot. Therefore, this review aimed to give insight into the promising applications of LAB-bacteriocins in preventing intestinal diseases, such as colonic cancer, Helicobacter pylori infections, multidrug-resistant infection-associated colitis, viral gastroenteritis, inflammatory bowel disease, and obesity disorders. Moreover, we highlighted the recent research on bacteriocins promoting gastrointestinal health. The review also provided insights into the proposed mechanisms, challenges and opportunities, trends and prospects. In addition, a SWOT analysis was conducted on the potential applications. Based on properties, biosafety, and health functions of LAB-bacteriocins, we conclude that the future applications of LAB-bacteriocins are promising in promoting gastrointestinal health. Further in vivo trials are needed to confirm these potential effects of LAB-bacteriocins interventions.

Gut Distribution, Impact Factor, and Action Mechanism of Bacteriocin-Producing Beneficial Microbes as Promising Antimicrobial Agents in Gastrointestinal Infection

Gastrointestinal (GI) infection by intestinal pathogens poses great threats to human health, and the therapeutic use of antibiotics has reached a bottleneck due to drug resistance. The developments of antimicrobial peptides produced by beneficial bacteria have drawn attention by virtue of effective, safe, and not prone to developing resistance. Though bacteriocin as antimicrobial agent in gut infection has been intensively investigated and reviewed, reviews on that of bacteriocin-producing beneficial microbes are very rare. It is important to explicitly state the prospect of bacteriocin-producing microbes in prevention of gastrointestinal infection towards their application in host. This review discusses the potential of gut as an appropriate resource for mining targeted bacteriocin-producing microbes. Then, host-related factors affecting the bacteriocin production and activity of bacteriocin-producing microbes in the gut are summarized. Accordingly, the multiple mechanisms (direct inhibition and indirect inhibition) behind the preventive effects of bacteriocin-producing microbes on gut infection are discussed. Finally, we propose several targeted strategies for the manipulation of bacteriocin-producing beneficial microbes to improve their performance in antimicrobial outcomes. We anticipate an upcoming emergence of developments and applications of bacteriocin-producing beneficial microbes as antimicrobial agent in gut infection induced by pathogenic bacteria.

Production and SERS characterization of bacteriocin-like inhibitory substances by latilactobacillus sakei in whey permeate powder: exploring natural antibacterial potential

Bacteriocins are antimicrobial compounds that have awakened interest across several industries due to their effectiveness. However, their large-scale production often becomes unfeasible on an industrial scale, primarily because of high process costs. Addressing this challenge, this work analyzes the potential of using low-cost whey permeate powder, without any supplementation, to produce bacteriocin-like inhibitory substances (BLIS) through the fermentation of Latilactobacillus sakei. For this purpose, different concentrations of whey permeate powder (55.15 gL-1, 41.3 gL-1 and 27.5 gL-1) were used. The ability of L. sakei to produce BLIS was evaluated, as well as the potential of crude cell-free supernatant to act as a preservative. Raman spectroscopy and surface-enhanced Raman scattering (SERS) provided detailed insights into the composition and changes occurring during fermentation. SERS, in particular, enhanced peak definition significantly, allowing for the identification of key components, such as lactose, proteins, and phenylalanine, which are crucial in understanding the fermentation process and BLIS characteristics. The results revealed that the concentration of 55.15 gL-1 of whey permeate powder, in flasks without agitation and a culture temperature of 32.5 °C, presented the highest biological activity of BLIS, reaching 99% of inhibition of Escherichia coli and Staphylococcus aureus with minimum inhibitory concentration of 36-45%, respectively. BLIS production began within 60 h of cultivation and was associated with class II bacteriocins. The results demonstrate a promising approach for producing BLIS in an economical and environmentally sustainable manner, with potential implications for various industries.

Functional Effects of Probiotic Lactiplantibacillus plantarum in Alleviation Multidrug-Resistant Escherichia coli-Associated Colitis in BALB/c Mice Model

Multidrug-resistant Escherichia coli (MDR-E. coli) is a global health concern. Lactic acid bacteria (LAB) are important probiotics that have beneficial effects on health, and in recent years, their influences in preventing foodborne pathogens-induced colitis have attracted much attention. Therefore, this study aimed to investigate the oral administration of Lactiplantibacillus plantarum NWAFU-BIO-BS29 as an emerging approach to alleviate MDR-E. coli-induced colitis in BALB/c mice model. To illustrate the mode of action of NWAFU-BIO-BS29 interventions with the gut microbiota and immune responses, the changes on the colonic mucosal barrier, regulatory of the gene expressions of inflammatory cytokines, re-modulating the intestinal microflora, and changes in physiological parameters were studied. The results indicated that daily supplementation of 200 µL fresh bacteria for 7 days had ameliorated the associated colitis and partially prevented the infection. The modes of action by ameliorating the inflammatory response, which destructed villous and then affected the intestinal barrier integrity, reducing the secretion of interleukins (6 and β) and tumor necrosis factor (TNF-α) in serum by 87.88-89.93%, 30.73-35.98%, and 19.14-22.32%, respectively, enhancing the expressions of some epithelial integrity-related proteins in the mouse mucous layer of mucins 2 and 3, Claudin-1, and Occludin by 130.00-661.85%, 27.64-57.35%, 75.52-162.51%, and 139.36-177.73%, respectively, and 56.09-73.58% for toll-like receptor (TLR4) in colon tissues. Notably, the mouse gut microbiota analysis showed an increase in the relative abundance of beneficial bacteria, including Lactobacillus, Bacteriodales bacterium, Candidatus Saccharimonas, Enterorhabdus, and Bacilli. Furthermore, the probiotic promoted the proliferation of epithelia and goblet cells by increasing short-chain fatty acids (SCFAs) levels by 19.23-31.39%. In conclusion, L. plantarum NWAFU-BIO-BS29 has potential applications and can be considered a safe dietary supplement to ameliorate the colitis inflammation symptoms of MDR-E. coli infection.

Oral Synergism of Egg-White-Derived Peptides (EWDP) and Curcumin for Colitis Mitigation via Polysaccharide/Cyclodextrin Metal-Organic Framework-Based Assemblies

Recently, oral deliverable strategies of multiple nutraceuticals for ulcerative colitis (UC) mitigation have attracted increasing attention. This study aimed to fabricate facile oral assemblies loaded with egg-white-derived peptides (EWDP) and curcumin based on carboxymethyl chitosan (CMCS) and an γ-cyclodextrin metal-organic framework (MOF). Herein, outer CMCS could coassemble with EWDP (both nutraceuticals and building blocks) into cobweb-like fibrils to promote bridging with inner MOF via coordinative noncovalent interactions (hydrogen bonding, hydrophobic interaction, and electrostatic interaction). Compared with conventional γ-cyclodextrin/MOF-based composites, the above coassembly could also endow the biocompatible assemblies with superior nanoscale colloidal properties, processing applicability (curcumin storage stability, bioaccessibility, and aqueous solubility), and bioactivity. Moreover, the oral synergism of EWDP and curcumin (initially nonsynergistic) for UC mitigation was achieved by alleviating inflammatory damage and gut microbiota imbalance. Overall, the novel assemblies could be a promising amplifier and platform to facilitate oral formulations of various nutraceuticals for food processing and UC relief.

Improvement of inflammatory bowel disease by lactic acid bacteria-derived metabolites: a review

Lactic acid bacteria (LAB) plays a crucial role in the establishment and maintenance of host health, as well as the improvement of some diseases. One of the major modes is the secretion of metabolites that may be intermediate or end products of the LAB's metabolism. In this review, we summarized some common metabolites (particularly short-chain fatty acids [SCFAs], bacteriocin, and exopolysaccharide [EPS]) from LAB in fermented foods and the gut for the first time. The effects of LAB-derived metabolites (LABM) on inflammation, oxidative stress, the intestinal barrier, and gut microbiota in inflammatory bowel disease (IBD) model are also discussed. The discovery of LABM and identification of IBD biomarkers are mainly attributed to the development of metabolomics technologies, especially nuclear magnetic resonance (NMR), gas chromatography-mass spectrometry (GC-MS), and liquid chromatography tandem mass spectrometry (LC-MS). The application of these metabolomics technologies in identification of LABM and IBD biomarkers are also summarized and analyzed. Although the beneficial effects of some LABM have been explored, undiscovered metabolites and their functions still need further investigations.

Potential Impact of Combined Inhibition by Bacteriocins and Chemical Substances of Foodborne Pathogenic and Spoilage Bacteria: A Review

In recent years, food safety caused by foodborne pathogens and spoilage bacteria has become a major public health problem worldwide. Bacteriocins are a kind of antibacterial peptide synthesized by microbial ribosomes, and are widely used as food preservatives. However, when used individually bacteriocins may have limitations such as high cost of isolation and purification, narrow inhibitory spectrum, easy degradation by enzymes, and vulnerability to complex food environments. Numerous studies have demonstrated that co-treatment with bacteriocins and a variety of chemical substances can have synergistic antibacterial effects on spoilage microorganisms and foodborne pathogens, effectively prolonging the shelf life of food and ensuring food safety. Therefore, this paper systematically summarizes the synergistic bacteriostatic strategies of bacteriocins in combination with chemical substances such as essential oils, plant extracts, and organic acids. The impacts of bacteriocins when used individually and in combination with other chemical substances on different food substrates are clarified, and bacteriocin-chemical substance compositions that enhance antibacterial effectiveness and reduce the potential negative effects of chemical preservatives are highlighted and discussed. Combined treatments involving bacteriocins and different kinds of chemical substances are expected to be a promising new antibacterial method and to become widely used in both the food industry and biological medicine.

Protective effect of plantaricin bio-LP1 bacteriocin on multidrug-resistance Escherichia Coli infection by alleviate the inflammation and modulate of gut-microbiota in BALB/c mice model

The rapid spread of multidrug-resistant pathogens with the low efficacy of common antibiotics for humans and animals in its clinical therapeutics are a global health concern. Therefore, there is a need to develop new treatment strategies to control them clinically. The study aimed to evaluate the effects of Plantaricin Bio-LP1 bacteriocin produced from Lactiplantibacillus plantarum NWAFU-BIO-BS29 to alleviate the inflammation caused by multidrug-resistance Escherichia Coli (MDR-E. coli) infection in BALB/c mice-model. The focus was given on aspects linked to the mechanism of the immune response. Results indicated that Bio-LP1 had highly promising effects on partially ameliorating MDR-E. coli infection by reducing the inflammatory response through inhibiting the overexpression of proinflammatory-cytokines such as secretion of tumor necrosis factor (TNF-α) and interleukin (IL-6 and IL-β) and strongly regulated theTLR4 signaling-pathway. Additionally, avoided the villous destruct, colon length shortening, loss of intestinal barrier integrity, and increased disease activity index. Furthermore, significantly increased the relative abundance of beneficial-intestinal-bacteria including Ligilactobacillus, Enterorhabdus, Pervotellaceae, etc. Finally, improved the intestinal mucosal barrier to alleviate the pathological damages and promote the production of short-chain fatty acids (SCFAs) a source of energy for the proliferation. In conclusion, plantaricin Bio-LP1 bacteriocin can be considered a safe alternative to antibiotics against MDR-E. coli-induced intestinal inflammation.

Postbiotics as potential new therapeutic agents for sepsis

Sepsis is the main cause of death in critically ill patients and gut microbiota dysbiosis plays a crucial role in sepsis. On the one hand, sepsis leads to the destruction of gut microbiota and induces and aggravates terminal organ dysfunction. On the other hand, the activation of pathogenic gut flora and the reduction in beneficial microbial products increase the susceptibility of the host to sepsis. Although probiotics or fecal microbiota transplantation preserve gut barrier function on multiple levels, their efficacy in sepsis with intestinal microbiota disruptions remains uncertain. Postbiotics consist of inactivated microbial cells or cell components. They possess antimicrobial, immunomodulatory, antioxidant and antiproliferative activities. Microbiota-targeted therapy strategies, such as postbiotics, may reduce the incidence of sepsis and improve the prognosis of patients with sepsis by regulating gut microbial metabolites, improving intestinal barrier integrity and changing the composition of the gut microbiota. They offer a variety of mechanisms and might even be superior to more conventional 'biotics' such as probiotics and prebiotics. In this review, we present an overview of the concept of postbiotics and summarize what is currently known about postbiotics and their prospective utility in sepsis therapy. Overall, postbiotics show promise as a viable adjunctive therapy option for sepsis.