Probiotics and Antimicrobial Proteins最新文献

Turmeric, referred to as "Golden Spice of India," belongs to Zingiberaceae family is cultivated in South-eastern and North-eastern regions of India, where it displays the regional diversity. In this study, turmeric rhizomes of Curcuma longa (yellow turmeric) from the South-eastern India and Curcuma caesia (black turmeric) from North-eastern India were collected. Proteins from these rhizome samples were extracted by using four different pH based buffer systems. The sequentially purified peptide filtrates obtained through ultrafiltration with 10 kDa and 3 kDa cut off membranes were quantified and assessed for their antioxidant potential by FRAP, NOS, DPPH and ABTS assays. The results showed that the highest antioxidant activities were observed in the Phosphate (pH 7.0) and Tris-HCl (pH 8.0) buffers. Further analysis of the 3 kDa filtrates from both turmeric samples by using HPLC confirmed the presence of peptides, which were subsequently identified by MALDI-TOF MS. The peptides identified in this study exhibited the promising bioactive potential based on their sequences and showed the less cleaving potential evaluated by insilico peptideCutter analysis. Future research will focus on validating these activities through comprehensive experimental approaches, including cell-based antioxidant, mechanistic studies, and antimicrobial evaluations. Such investigations will be essential to confirm their biological relevance and to determine its suitability for nutraceutical applications.

Developing novel probiotics can help in preventing livestock diarrhea and associated intestinal diseases. Lactic acid bacteria (LAB) are symbiotic intestinal bacteria, which contribute to gastrointestinal tract health. An LAB strain, designated L. johnsonii RS-7, was isolated from the feces of healthy adult pigs and was resistant to acidic conditions and bile salts. In vitro evaluation showed significant antioxidant and anti-inflammatory properties, suggesting its potential application in alleviating intestinal inflammation. An artificially induced colitis model was established in mice to investigate the efficacy of L. johnsonii RS-7. Results indicated that mice administered water containing 3% DSS developed pronounced colitis symptoms, characterized by weight loss, elevated disease activity index, shortened colon length, microvilli shedding, tight junction disruption, reduced goblet cell counts, suppression of anti-inflammatory cytokines, activation of pro-inflammatory cytokines and the TLR4/MyD88/NF-κB signaling pathway, and impaired gut microbiota diversity. These suggest that oral administration of L. johnsonii RS-7 significantly alleviated colitis symptoms. In summary, L. johnsonii RS-7 acted as a probiotic by inhibiting activation of the TLR4/MyD88/NF-κB pathway.

In this study, we aimed to develop a novel antimicrobial peptide (AMP) design strategy via a localization-based motif combination approach to target Gram-negative and Gram-positive pathogenic bacteria. Peptide sequences with high inhibitory activity against Escherichia coli and Staphylococcus aureus were extracted from Database of Antimicrobial Activity and Structure of Peptides (DBAASP) to form two separate datasets for Gram-negative and Gram-positive bacteria, respectively. The peptide sequences in the datasets were segmented into three fragments based on their N-terminal, C-terminal, and central positions, and their statistical significance was scored. The top-scoring fragments were assembled based on their segment-specific positions to generate candidate peptides. The several properties of the candidate peptides were predicted in silico, and the peptides exhibiting the highest antibacterial activity against Gram-positive and Gram-negative bacteria were selected for subsequent synthetic production. The peptides showed membrane deformation effects against the target bacterial strains, and their minimum inhibitory concentration (MIC) values were determined to be between 4 and 16 µg/mL for Gram-negative strains and 4-128 µg/mL for Gram-positive strains. The maximum therapeutic index of the peptides varied between 86 and 129, and their docking scores were found to be higher than known antimicrobial agents, such as nisin and polymyxin B. These results suggest that the designed peptides may serve as effective agents against pathogenic bacteria, including drug-resistant strains, and represent a promising alternative to traditional antibiotics.

Acute hypoxia stress poses a significant challenge in aquaculture, not only compromising gut health but also resulting in substantial economic losses. Using an integrated multi-omics approach, this study demonstrates that hypoxia severely disrupts the intestinal function of yellow catfish (Pelteobagrus fulvidraco), specifically manifesting as phospholipid metabolism disorders, inhibited fatty acid β-oxidation, reduced short-chain fatty acid (SCFA) synthesis, imbalanced gut microbiota (e.g., decreased levels of beneficial lactic acid bacteria Lactococcus and Clostridium sensu stricto 1), and downregulation of detoxification pathways mediated by cytochrome P450. Building upon the previously isolated and identified high-yield SCFA-producing probiotic Clostridium butyricum B3 from yellow catfish in early work, this research further investigated the efficacy and mechanisms of B3 supplementation in mitigating hypoxia-induced intestinal barrier damage in yellow catfish. The results indicated that the supplementation of C. butyricum B3, particularly at a dose of 3.0 × 10⁷ CFU/g, significantly reduced histological damage, enhanced the expression of key tight junction proteins (such as ZO-1 and Claudin), and modulated hypoxia-inducible factor signaling pathways (including HIF-1α, FIH, and PHD). Furthermore, the application of C. butyricum B3 restored microbial ecological balance by promoting the growth of beneficial bacteria like Cetobacterium and inhibiting potential pathogens such as Acinetobacter. In conclusion, these findings underscore the potential of C. butyricum B3 as a novel probiotic strategy for enhancing fish hypoxia tolerance and maintaining intestinal integrity, offering valuable insights for sustainable aquaculture practices.

Per- and polyfluoroalkyl substances (PFAS) are highly persistent environmental contaminants that pose a significant threat to ecosystems and human health due to their exceptional chemical stability and resistance to degradation. Conventional remediation methods-such as activated carbon adsorption, ion exchange, and advanced oxidation-primarily transfer PFAS between phases rather than achieving complete mineralization, resulting in the generation of secondary waste. Microbial bioremediation has emerged as a promising, sustainable strategy. Several bacteria, fungi, and cyanobacteria can transform or defluorinate PFAS under environmentally relevant conditions, yielding less fluorinated intermediates. Enzymatic studies have identified oxygenases and reductive dehalogenases as key catalysts in the cleavage of C-F bonds. Moreover, recent evidence indicates that the gut microbiota can adsorb and sequester PFAS, facilitating fecal elimination and reducing systemic toxicity. Advances in synthetic biology now enable the engineering of microbial systems, including probiotic strains, with enhanced PFAS uptake and degradation capabilities. However, significant challenges remain; current microbial pathways primarily act through partial transformation rather than complete mineralization, often accumulating stable fluorinated intermediates. True mineralization is constrained by low enzymatic efficiency, narrow substrate specificity, and the difficulty of translating laboratory success to complex environmental matrices. This review critically synthesizes current progress in microbial and probiotic bioremediation of PFAS, emphasizing enzymatic mechanisms, microbial pathways, and integration with conventional treatment systems. By engaging with these limitations alongside promising advances, we provide a balanced assessment of the feasibility of microbial and engineered probiotic approaches, highlighting knowledge gaps and future directions for developing safe, scalable detoxification technologies.

Probiotics have attracted considerable attention in recent years due to their potential in modulating the gut microbiota, enhancing immune function, and contributing to the management of metabolic disorders, inflammatory diseases, and neuropsychiatric conditions. However, their clinical efficacy is often compromised by harsh gastrointestinal conditions such as gastric acid, bile salts, and digestive enzymes that significantly reduce probiotic viability. Moreover, current formulations face challenges in terms of bioavailability, targeted delivery, and consistency of therapeutic outcomes. To address these limitations, a variety of delivery strategies have been developed, including colon- and inflammation-targeted systems, genetically engineered and surface-modified probiotics, microencapsulation technologies with material innovations and functional enhancements, as well as inorganic and organic nanocarrier platforms. In parallel, interdisciplinary approaches such as smart-responsive systems, biomimetic technologies, microbiota remodeling, and synthetic biology have been increasingly employed to achieve precise release and sustained colonization in the host. This review systematically summarizes recent advances in probiotic delivery technologies, covering diverse engineering strategies and material platforms. It also critically examines key challenges in clinical translation, including formulation stability, inter-individual variability, regulatory inconsistencies, and long-term safety concerns, aiming to provide a comprehensive reference for the optimization and high-quality development of probiotic delivery systems. Aiming to provide a comprehensive reference and a forward-looking framework to guide the rational design of next-generation probiotic biotherapeutics.

The use of probiotics in aquaculture has emerged as a sustainable strategy for enhancing fish health and reducing the use of antibiotics, thereby serving the cause of One Health. In the present study, we employed a novel, distinctive, rigorous, and multi-tiered plate-based screening methodology to isolate spore-forming probiotic bacterial strains from fish market drain water for aquaculture applications. Based on their non-pathogenicity, potential for extracellular enzyme production, bile salt tolerance, and biofilm formation capabilities, three isolates, FM1, FM2, and FM4, with positive performance for all tested assays, were chosen and comprehensively characterized. Strain FM2, identified based on 16S rRNA gene sequence homology as Bacillus sp., was highly effective, exhibiting high sporulation efficiency (91%) and yield (9.3 × 10⁸ CFU /mL). It also had broad-spectrum antimicrobial activity against eight common fish pathogens, with high biofilm-formation inhibition, and preformed biofilm-disruption potential. The strain further demonstrated excellent adhesive capabilities (97% auto-aggregation at 24 h, significant co-aggregation with pathogens, and high cell surface hydrophobicity), robust antioxidant activity, and notable exopolysaccharide production. It was susceptible to key antibiotics, including gentamicin, imipenem, amikacin, and ciprofloxacin, ensuring biosafety. Its spores can withstand environmental and gastrointestinal stress conditions, such as heat (110 °C), UV light, lysozyme, and bile salts, and survive in simulated gastric and intestinal fluids. Thus, FM2 is a promising, safe, and multi-functional probiotic for aquaculture, capable of improving fish gut health, inhibiting pathogens, and surviving under challenging environmental conditions, and has enormous potential for commercialisation in aquaculture.

Probiotics are living microorganisms that are consumed to get diverse health benefits. These probiotic organisms through four basic mechanisms aid and improve our health which includes synthesis of short-chain fatty acids (SCFAs), augmentation of epithelial barriers, immunomodulation, and production of neuroactive compounds. All these together help in alleviation of psychological disorders, dental caries, improves kidney disorder, helps in prevention of heart diseases, allergies like dermatitis, respiratory allergies and colon and other types of cancer. One of the most beneficial impacts of probiotics is prevention of inflammatory bowel disease. It eases inflammation by increasing the levels of anti-inflammatory cytokines and reducing pro-inflammatory levels. Probiotics also synthesis vitamins like Vitamin K, E, and antioxidants which prevent ageing, oxidative stress, cellular damage and apoptosis of epithelial cells. Probiotics have shown promising results in different studies and are thought to be an active component of alternative medicine with negligible side effects.