Probiotics and Antimicrobial Proteins最新文献

Ice creams are consumable foods that have the potential to be used as probiotic carriers. The purpose of this study was to evaluate the bacteriological quality (i.e., antibiotic response, bacterial identification, and fermentation using bacterial culture) of ice creams. The 16S rDNA sequence analysis was used to identify the isolates, and the disc diffusion method was used to measure antibiotic responses. The total viable counts (TVC) of all the branded ice cream samples were within the permitted limits (1.0 × 10⁵ cfu/ml) stipulated by Bangladesh guidelines. On the other hand, locally produced ice cream was not within permitted limits, exceeding these criteria and suggesting possible health hazards. Six (6) antibiotic-resistant bacteria were identified by 16S rDNA sequencing, namely Brevundimonas sp., Exiguobacterium sp., Brevundimonas terrae-IARI-ABR-33., Pseudomonas geniculate, Stenotrophomonas sp., and Brevundimonas terrae. Lactobacillus acidophillus had antagonistic activity against test pathogens, exhibiting varied degrees of inhibition. To make probiotic ice cream, a standard ice cream mix was fermented using L. acidophillus bacteria. After the fermentation mixture was frozen for storage, there was a one log cycle decline in Lactobacillus viable counts. So, it may be concluded that probiotic ice cream created with L. acidophillus will be safer, healthier, and more hygienic than industrial or locally produced ice cream.

Gut brain axis can affect the incidence of Alzheimer's disease (AD). Probiotics restore the homeostasis of gut dysbiosis and prevent AD. Here, we evaluated the impact of Saccharomyces boulardii on rats with lipopolysaccharide (LPS)-induced amyloidogenesis. Rats were classified into four groups: (1) Control (saline), (2) LPS 250 µg/kg (saline + LPS), (3) S. boulardii (10¹⁰ CFU/mL/rat), and (4) S. boulardii (10¹⁰ CFU/mL/rat) + LPS (250 μg/kg). The passive behavioral test, Western blotting, and immunohistochemistry were done using the animal hippocampi. Step-through latency (STL) indicated that the LPS-treated group had decreased memory retrieval compared to the control group. The LPS group had increased hippocampal levels of amyloid-β peptide, amyloid-β precursor protein (APP), and β-secretase (BACE). Administration of the S. boulardii before LPS prolonged STL which has been shortened in the LPS group (P < 0.05). In the LPS + S group, S. boulardii reduced the levels of APP significantly compared to the LPS group (P < 0.01). S. boulardii mitigated Aβ buildup and memory dysfunction caused by LPS through modulating the APP, BACE1, and Aβ pathways. Future studies are required to explain the neuroprotective effects of S. boulardii, since it could be a novel therapy or prevention strategy for AD.

This paper provides a comprehensive review of antimicrobial peptides (AMPs) derived from Bacillus spp. The classification and structure of Bacillus-derived AMPs encompass a diverse range. There are 89 documented Bacillus-derived AMPs, which exhibit varied sources, amino acid sequences, and molecular structures. These AMPs can be categorized into classes I, Ia, IIa, IIb, IIc, and IId. The synthesis pathway of the AMPs primarily involves either ribosomally synthesized or non-ribosomally synthesized approaches. Additionally, the antimicrobial activity of these AMPs is versatile, targeting bacteria, fungi, and viruses, through disrupting intracellular DNA and the cell wall and membrane, as well as modulating immune responses. Moreover, the Bacillus-derived AMPs demonstrate promising application in the pharmaceutical industry, environmental protection, food preservation, and bio-control in agriculture. The commonly employed strategies for enhancing the production of Bacillus-derived AMPs involve optimizing cultivation conditions, implementing systems metabolic engineering, employing genome shuffling techniques, optimizing promoters, and improving expression host optimization. This review can provide a valuable reference for comprehending the current research status on advancements and sustainable production of Bacillus-derived AMPs.

Foodborne bacterial enteritis is a common clinical disease, and its incidence has risen globally. To screen for functional Bacillus strains with anti-inflammatory properties, tolerance to acid and bile salts, and antagonism against Salmonella, 22 strains of Bacillus were employed as candidate strains in this study. An inflammatory cell model was established using J774-Dual NF-κB/IRF reporter macrophages to identify anti-inflammatory Bacillus. The candidate Bacillus strains were assessed through tolerance to acid and bile salts and antibacterial assays, and their inhibitory effects on the inflammatory responses triggered by S. Enteritidis infection were investigated. The findings demonstrated that B. licheniformis B410 was successfully screened, possessing a significant anti-inflammatory effect by suppressing the NF-κB and IRF signaling pathways. B410 exhibited excellent tolerance to acid and bile salts and displayed a favorable antibacterial effect against Salmonella. Co-incubation of B410 with RAW264.7 macrophages did not influence the cell viability. B. licheniformis B410 could significantly inhibit the expression of pro-inflammatory cytokines IL-1β and TNF-α induced by LPS and promote the expression of the anti-inflammatory cytokine IL-10. Additionally, B410 could markedly inhibit the activation of NF-κB and the production of inflammatory cytokines caused by S. Enteritidis infection in macrophages. This study successfully screened a new strain of B. licheniformis B410 that simultaneously had the capabilities of anti-inflammation, acid and bile salt tolerance, and antagonism against Salmonella, providing a new approach for the screening of functional anti-inflammatory probiotics and the development of anti-inflammatory probiotic therapeutic preparations.

Various types of liver or hepatic diseases cause the death of about 2 million people worldwide every year, of which 1 million die from the complications of cirrhosis and another million from hepatocellular carcinoma and viral hepatitis. Currently, the second most common solid organ transplant is the liver, and the current rate represents less than 10% of global transplant requests. Hence, finding new approaches to treat and prevent liver diseases is essential. In liver diseases, the interaction between the liver, gut, and immune system is crucial, and probiotics positively affect the human microbiota. Probiotics are a non-toxic and biosafe alternative to synthetic chemical compounds. Health promotion by lowering cholesterol levels, stimulating host immunity, the natural gut microbiota, and other functions are some of the activities of probiotics, and their metabolites, including bacteriocins, can exert antimicrobial effects against a broad range of pathogenic bacteria. The present review discusses the available data on the results of preclinical and clinical studies on the effects of probiotic administration on different types of liver diseases.

Probiotics are known to have favorable effects on human health. Nevertheless, probiotics are not always beneficial and can cause unintended adverse effects such as bacteremia and/or inflammation in immunocompromised patients. In the present study, we investigated the effects of probiotics on the regulation of bone metabolism under different health conditions and delivery routes. Intragastric administration of Lactiplantibacillus plantarum to ovariectomized mouse models for mimicking post-menopausal osteoporosis in humans substantially ameliorated osteoporosis by increasing bone and mineral density. In contrast, such effects did not occur in normal healthy mice under the same condition. Interestingly, however, intraperitoneal administration of L. plantarum induced bone destruction by increasing osteoclast differentiation and decreasing osteoblast differentiation. Furthermore, when L. plantarum was implanted into mouse calvarial bone, it potently augmented bone resorption. Concordantly, L. plantarum upregulated osteoclastogenesis and downregulated osteoblastogenesis in in vitro experiments. These results suggest that L. plantarum can have distinct roles in the regulation of bone metabolism depending on bone health and the delivery route.

An elevated abundance of Escherichia coli (E. coli) has been linked to the onset and progression of inflammatory bowel disease (IBD). Regenerating islet-derived family member 4 (Reg4) has been isolated from patients with ulcerative colitis (UC), but its functions and involved mechanisms in intestinal inflammation are remain incompletely understood. Therefore, we generated an intestinal conditional Reg4 knockout mouse (Reg4^ΔIEC) to address this gap by utilizing murine models of enteropathogenic E. coli (EPEC)-infected bowel and dextran sulfate sodium (DSS)-induced colitis. We here demonstrate that REG4 is increased in diseased intestinal mucosa of pediatric IBD, primarily expressed and enriched in intestinal goblet cells. Deficiency of Reg4 in the intestinal epithelium of mice leads to an increase in the Phylum Proteobacteria and in the family Enterobacteriaceae. Administration of recombinant Reg4 protein significantly mitigates EPEC-induced intestinal inflammation and injury in a murine model. In vitro, Reg4 protein suppresses the growth and motility of EPEC, subsequently reducing their adhesion and invasion to the intestinal epithelial cells. Mechanistically, the conserved mannan-binding sites (like C-lectin domain) are essential for Reg4 antimicrobial activity. Moreover, loss of Reg4 in mice increases susceptibility to DSS-induced colitis, which can be improved by gentamicin (GM), an antibiotic for Gram-negative bacteria. In conclusion, intestinal goblet cell-derived Reg4 is crucial for protection against experimental colitis, likely due to its bactericidal activity against EPEC.

Probiotics are microorganisms that provide health benefits at adequate doses and exhibit notable antioxidant and antimicrobial activities. These properties play crucial roles in combating chronic diseases linked to oxidative stress and antimicrobial resistance. This review aimed to summarize the antioxidant and antimicrobial properties of probiotics determined in in vitro studies and discuss mechanistic actions and analysis methods. The MEDLINE (PubMed), Web of Science, Scopus, Science Direct, and Embase databases were utilized. The included articles demonstrated the antioxidant and antimicrobial activities of both isolated and food matrix-associated probiotics, with the most common genera being Lactobacillus, Bifidobacterium, Saccharomyces, and Streptococcus. Antioxidant activity was the most studied property, yielding varied results attributed to evaluation tests and probiotic strain. Antibacterial activity was consistently reported in all studies. Additionally, fermentation with probiotic microorganisms improved the content and bioaccessibility of bioactive compounds. In conclusion, analysis results highlight the antioxidant and antimicrobial activity of probiotics reported in in vitro studies. They enhance bioactive content and bioaccessibility and produce novel beneficial metabolites during fermentation. These results reinforce the therapeutic promise of probiotics associated with plant matrices and indicate the need for clinical studies to confirm their efficacy in improving human health.

Pancreatic cancer is influenced by interactions between cancer cells and the tumor microenvironment (TME), including tumor-infiltrating lymphocytes (TILs). Specifically, CD8 + T cells impact prognosis by eliminating cancer cells. Recent studies have revealed that microbiomes are present in pancreatic tissues and may affect tumor growth and immune responses. Additionally, recent studies revealed that the abundance of Bacteroides, Lactobacillus, and Peptoniphilus are associated with poor pancreatic cancer prognosis. This study investigates the role of oral probiotics in influencing pancreatic cancer outcomes. We retrospectively reviewed patients aged ≥ 18 years with pathologically confirmed pancreatic cancer from Seoul National University Hospital between January 2011 and January 2023. We investigated progression-free survival and overall survival between the control group and the probiotics group. Among pancreatic cancer patients undergoing palliative chemotherapy without radiotherapy and resection, there was a significant difference in overall survival (OS) when comparing the control group to the probiotics group (median: 10 months (9-11) vs. 12 months (9-19), p = 0.026). Regardless of the type of probiotics, oral probiotics may have a positive impact, but further research is still needed to understand the underlying immunological mechanisms.

This study aimed to investigate the effect of a multi-strain probiotic (Bifidobacterium B8101, Lactobacillus L8603, Saccharomyces bayanus S9308, Enterococcus SF9301), betaine, and their combination on intestinal epithelial development and growth performance in broilers. A total of 2800 one-day-old Ross 308 chickens were randomly divided into four groups: control (Ctrl) fed with a basal diet, multi-strain probiotic (Pb) group fed with basal diet + 100 mg/day/bird probiotic (1-14 d), betaine (Bet) fed with basal diet + 0.1% betaine (1-35 d), and a combination (Pb&Bet) fed with both probiotics and betaine. Each group was set with 10 replicates, with 70 chickens in each replicate. Result showed that betaine significantly increased the body weight (BW) of broilers at 14 d of age and decreased the feed conversion ratio (FCR) from 1 to 14 d of age. Multi-strain probiotic significantly increased BW at 21 and 35 d of age, and decreased FCR from 15 to 21 d of age. Pb&Bet group exhibited a higher BW but lower FCR than Ctrl throughout entire experiment (p < 0.05). Consistently, Pb&Bet group had a higher pectoralis muscle weight, fiber diameter and cross-sectional area compared to Ctrl group (p < 0.05). Pb&Bet group also increased villus height and the ratio of villus height to crypt depth (V/C) in duodenum at both 21 d and 35 d of age. Moreover, at 35 d of age, the mucin 2 (MUC2) expression in duodenum and jejunum was significantly increased in Pb&Bet group, and the interaction of betaine and probiotics was observed on claudin 1 (CLDN1), zonula occludens 1 (ZO1), and junctional adhesion molecule 2 (JAM2) expression in the ileum (p < 0.05). In conclusion, the combination of probiotics and betaine shows better potential for improving growth performance and promoting small intestinal development.