Anti-pathogenic Effects Research Articles

Enhanced antiviral defense against begomoviral infection in Nicotiana benthamiana through strategic utilization of fluorescent carbon quantum dots to activate plant immunity.

Owing to their unique physiochemical properties, low toxicity, antipathogenic effects and tunability, fluorescent carbon quantum dots (CQDs) represent a new generation of carbon-based nanomaterials. Despite the mounting research on the efficacy of CQDs against resilient plant pathogens, their potential ability to mitigate viral pathogens and the underlying molecular mechanism(s) remain understudied. In this study, we optimized the CQDs to maximize their antiviral effects against a highly pathogenic Begomovirus (cotton leaf curl Multan virus, CLCuMuV) and elucidated the mechanistic pathways associated with CQDs-mediated viral inhibition. To fine-tune the CQDs-induced antiviral effects against CLCuMuV and investigate the underlying molecular mechanisms,we used HR-TEM, XRD, FT-IR, XPS, and UV‒Vis spectrophotometry to characterize the CQDs. SPAD and FluorCam were used for physiological and photosynthetic performance analysis. Transcriptome, RT‒qPCR, integrated bioinformatics and molecular biology were employed to investigate gene expression, viral quantification and data validation. The application of fluorescent, hexagonal crystalline, UV-absorptive and water-soluble CQDs (0.01mg/ml) significantly reduced the CLCuMuV titer and mitigated viral symptoms in N. benthamiana at the early (5 dpi) and late (20 dpi) stages of infection. CQDs significantly increased the morphophysiological properties, relative chlorophyll contents and photosynthetic (Fv/Fm, QY_max, NPQ and Rfd) performance of the CLCuMuV-infected plants. While CLCuMuV infection disrupted plant immunity, the CQDs improved the antiviral defense response by regulating important immunity-related genes involved in endocytosis/necroptosis, Tam3-transposase, the ABC transporter/sphingolipid signaling pathway and serine/threonine protein kinase activities. CQDs potentially triggered TSS and TTS alternative splicing events in CLCuMuV-infected plants. Overall, these findings underscore the antiviral potential of CQDs, their impact on plant resilience, and their ability to modulate gene expression in response to viral stress. This study's molecular insights provide a foundation for further research on nanomaterial applications in plant virology and crop protection, emphasizing the promising role of CQDs in enhancing plant health and combating viral infections.

A Polyphenol Decorated Triplex Hybrid Biomaterial: Structure-Function, Release Profiles, Sorption, and Antipathogenic Effects.

Herein, nonwoven alkali modified flax substrates were coated with incremental levels of chitosan, followed by immobilization of tannic acid, via a facile "dip-coating" strategy to yield a unique hierarchal "triplex" hybrid biomaterial, denoted as "THB". The characterization of the physicochemical properties of THB employed complementary spectroscopic (IR, Raman, and NMR) techniques, which support the role of hydrogen bonding and electrostatic interactions between the components: chitosan as the secondary biopolymer coating and the tertiary adsorbed polyphenols. XRD and SEM techniques provide further structural insight that confirms the unique semicrystalline nature and porous hierarchal structure of the biocomposite. The THBs present a polyphenol kinetic release profile that follows the Korsmeyer-Peppas model that concurs with Fickian diffusion for heterogeneous polymer systems. Furthermore, these systems demonstrate a tailored solvent uptake capacity (up to 4 g/g) in aqueous PBS media. Antipathogenic activity tests revealed 95% elimination of pathogens (E. coli, S. aureus, and C. albicans) at a dose of 50 mg for the THB system. The trend in the structure-property relationships for the THB systems indicates synergistic effects of electrostatic multiform interactions between protonated chitosan and the polyphenol units. Herein, we report the first example of a unique hierarchal biomaterial via a facile design strategy for diversiform roles as responsive adsorbents for environmental remediation to biomedical applications (e.g., controlled release, topical administration, or antimicrobial surface coatings).

Anti-pathogenic and probiotic-friendly effect of benzyloxy pyridine derivative impregnated into bacterial cellulose matrix

Bacterial cellulose (BC) has emerged as a promising biomaterial for biomedical applications due to its unique properties. In this study, firstly, the potential of BC as a carrier material for the originally synthesized benzyloxy pyridine derivative (BeOxP), and also an antimicrobial and probiotic bacteria-friendly (on Lactiplantibacillus plantarum 299v (LP299V®) (DSM 9843)) effect of BC- BeOxP was investigated. The BC- BeOxP composite material was developed using a simple and efficient method, ensuring the uniform dispersion of BeOxP within the BC matrix. Characterization of BeOxP has been carried out with High-Resolution Mass Spectroscopy (HRMS) and Nuclear Magnetic Resonance (NMR). Additionally, BC- BeOxP was characterized by Thermogravimetric analysis (TGA), Differential thermal analysis (DTA), Scanning Electron Microscopy (SEM), Texture analysis, and Fourier-transform infrared spectroscopy (FTIR), confirming the successful integration of BeOxP without compromising the structural integrity of BC. The mechanical properties of the BC- BeOxP composites were also evaluated to ensure their suitability for drug-carrying or food-packaging applications. Antimicrobial activity of the BC- BeOxP was analyzed against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922 while the probiotic-friendly effect was tested on Lactiplantibacillus plantarum 299v (LP299V®) (DSM 9843). The findings open avenues for further research of BC-based drug carriers or packaging materials for advanced biomedical applications.

Multifunctional Nanoemulsified Clinacanthus nutans Extract: Synergistic Anti-Pathogenic, Anti-Biofilm, Anti-Inflammatory, and Metabolic Modulation Effects against Periodontitis.

This study investigates the therapeutic potential of Clinacanthus nutans extracts, focusing on the 95% ethanol (95E) extract and its nanoemulsified form, against oral pathogens and their bioactive effects. The findings demonstrate potent antibacterial activity against Streptococcus mutans and Staphylococcus aureus, essential for combating periodontal diseases, and significant anti-biofilm properties crucial for plaque management. Additionally, the extracts exhibit promising inhibitory effects on α-glucosidase enzymes, indicating potential for diabetes management through glucose metabolism regulation. Their anti-inflammatory properties, evidenced by reduced nitric oxide production, underscore their potential for treating oral infections and inflammation. Notably, the nanoemulsified 95E extract shows higher efficiency than the conventional extract, suggesting a multifunctional treatment approach for periodontal issues and metabolic disorders. These results highlight the enhanced efficacy of the nanoemulsified extract, proposing it as an effective treatment modality for periodontal disease in diabetic patients. This research offers valuable insights into the development of innovative drug delivery systems using natural remedies for improved periodontal care in diabetic populations.

Biogenic Syntheses of AgNPs With Leaf Extract Abution indicum and Its Application for Antimicrobial and Photocatalytic Activity

ABSTRACTThe biogenic synthesis of silver nanoparticles (AgNPs) with leaf extract Abution indicum was done, and those were characterized by ultraviolet–visible spectroscopy (UV–vis), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), powder X‐ray diffraction (PXRD), field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM) with energy‐dispersive X‐ray (EDX) spectroscopy. The analysis by UV–vis spectroscopy showed a peak of 450 nm, and DLS and zeta potential were utilized to determine the size distribution of the biosynthesized Abution indicum–AgNPs (AI‐AgNPs) with a size range of 24–37 nm, and the X‐ray diffraction peak 38.096o was used to confirm that the crystalline structure of AI‐AgNPs. Furthermore, the antipathogenic effect of synthesized AgNPs and standard antibiotic (Ciprofloxacin) as studied the positive control in different types of bacterial pathogens likes Staphylococcus aureus and Escherichia Coli, with the zone of inhibition values of 9 mm. The synthesized AgNPs displayed excellent photocatalytic activity against reactive blue under sunlight than a UV light irradiation, and maximum degradation of 43% was achieved with 66 min of reaction time. In view of promising activity, the AgNPs could be used photocatalyst for the degradation of dyes in wastewater, and pomegranate leaf extract can be applied as eco‐benign and cost‐effective approach for AgNPs synthesis. Hence, the current findings suggest that Abutilon indicum is a valuable source for tailoring the potential of AgNPs toward various enhanced biological, photocatalytic, and adsorption activities. Consequently, the plant biological molecule‐mediated synthesized AI‐AgNPs could be excellent contenders for future therapeutic applications.

In Vitro Evaluation of Probiotic Properties and Anti-Pathogenic Effects of Lactobacillus and Bifidobacterium Strains as Potential Probiotics.

Probiotics restore gut microbial balance, thereby providing health-promoting effects to the host. They have long been suggested for managing intestinal disorders caused by pathogens and for improving gut health. This study evaluated the probiotic properties and anti-pathogenic effects of specific probiotic strains against the intestinal pathogens Staphylococcus aureus and Escherichia coli. The tested strains-Lactiplantibacillus plantarum LC27, Limosilactobacillus reuteri NK33, Lacticaseibacillus rhamnosus NK210, Bifidobacterium longum NK46, and Bifidobacterium bifidum NK175-were able to survive harsh conditions simulating gastric and intestinal fluids. These strains exhibited good auto-aggregation abilities (41.8-92.3%) and ideal hydrophobicity (30.9-85.6% and 38.3-96.1% for xylene and chloroform, respectively), along with the ability to co-aggregate with S. aureus (40.6-68.2%) and E. coli (38.6-75.2%), indicating significant adhesion levels to Caco-2 cells. Furthermore, these strains' cell-free supernatants (CFSs) demonstrated antimicrobial and antibiofilm activity against S. aureus and E. coli. Additionally, these strains inhibited gas production by E. coli through fermentative activity. These findings suggest that the strains tested in this study have potential as novel probiotics to enhance gut health.

Probiotics in Wound Healing.

Wound infections caused by opportunistic bacteria promote persistent infection and represent the main cause of delayed healing. Probiotics are acknowledged for their beneficial effects on the human body and could be utilized in the management of various diseases. They also possess the capacity to accelerate wound healing, due to their remarkable anti-pathogenic, antibiofilm, and immunomodulatory effects. Oral and topical probiotic formulations have shown promising openings in the field of dermatology, and there are various in vitro and in vivo models focusing on their healing mechanisms. Wound dressings embedded with prebiotics and probiotics are now prime candidates for designing wound healing therapeutic approaches to combat infections and to promote the healing process. The aim of this review is to conduct an extensive scientific literature review regarding the efficacy of oral and topical probiotics in wound management, as well as the potential of wound dressing embedding pre- and probiotics in stimulating the wound healing process.

Oral curcumin ameliorates acute murine campylobacteriosis

IntroductionHuman infections with the food-borne enteropathogen Campylobacter jejuni are responsible for increasing incidences of acute campylobacteriosis cases worldwide. Since antibiotic treatment is usually not indicated and the severity of the enteritis directly correlates with the risk of developing serious autoimmune disease later-on, novel antibiotics-independent intervention strategies with non-toxic compounds to ameliorate and even prevent campylobacteriosis are utmost wanted. Given its known pleiotropic health-promoting properties, curcumin constitutes such a promising candidate molecule. In our actual preclinical placebo-controlled intervention trial, we tested the anti-microbial and anti-inflammatory effects of oral curcumin pretreatment during acute experimental campylobacteriosis.MethodsTherefore, secondary abiotic IL-10-/- mice were challenged with synthetic curcumin via the drinking water starting a week prior oral C. jejuni infection. To assess anti-pathogenic, clinical, immune-modulatory, and functional effects of curcumin prophylaxis, gastrointestinal C. jejuni bacteria were cultured, clinical signs and colonic histopathological changes quantitated, pro-inflammatory immune cell responses determined by in situ immunohistochemistry and intestinal, extra-intestinal and systemic pro-inflammatory mediator measurements, and finally, intestinal epithelial barrier function tested by electrophysiological resistance analysis of colonic ex vivo biopsies in the Ussing chamber.Results and discussionWhereas placebo counterparts were suffering from severe enterocolitis characterized by wasting symptoms and bloody diarrhea on day 6 post-infection, curcumin pretreated mice, however, were clinically far less compromised and displayed less severe microscopic inflammatory sequelae such as histopathological changes and epithelial cell apoptosis in the colon. In addition, curcumin pretreatment could mitigate pro-inflammatory innate and adaptive immune responses in the intestinal tract and importantly, rescue colonic epithelial barrier integrity upon C. jejuni infection. Remarkably, the disease-mitigating effects of exogenous curcumin was also observed in organs beyond the infected intestines and strikingly, even systemically given basal hepatic, renal, and serum concentrations of pro-inflammatory mediators measured in curcumin pretreated mice on day 6 post-infection. In conclusion, the anti-Campylobacter and disease-mitigating including anti-inflammatory effects upon oral curcumin application observed here highlight the polyphenolic compound as a promising antibiotics-independent option for the prevention from severe acute campylobacteriosis and its potential post-infectious complications.

Discovery of a Biocontrol Strain Trichaptum laricinum: Its Metabolites and Antifungal Activity against Pathogenic Fungus Colletotrichum anthrisci.

Finding safe and environmentally friendly fungicides is one of the important strategies in modern pesticide research and development. In this work, the antipathogenic effects of the fungus Trichaptum laricinum against the anthracnose pathogen Colletotrichum anthrisci were studied. The EtOAc extract of T. laricinum showed remarkable antifungal activity against C. anthrisci with an inhibition rate of 50% at 256 μg/mL. Bioguided isolation of the cultural broth of T. laricinum produced four new drimane sesquiterpenes, trichalarins A-D (1-4), and six other metabolites (5-10). Their structures were established by extensive spectroscopic methods, quantum chemical calculations, and single-crystal X-ray diffraction. All compounds exhibited antifungal activity against C. anthrisci with minimum inhibitory concentrations (MICs) of 8-64 μg/mL in vitro. Further in vivo assay suggested that compounds 2, 6, and 9 could significantly inhibit C. anthrisci growth in avocado fruit with inhibition rates close to 80% at the concentration of 256 μg/mL, while compounds 2 and 6 had an inhibition rate over 90% at the concentration of 512 μg/mL. The EtOAc extract of T. laricinum had no inhibitory effect on Pinus massoniana seed germination and growth at the concentration of 2 mg/mL, showing good environmental friendliness. Thus, the fungus T. laricinum could be considered as an ideal biocontrol strain, and its metabolites provided a diverse material basis for the antibiotic agents.

A Study on the Antipathogenic Effects of Nanoemulsion Against V. parahaemolyticus in Shrimp Aquaculture: Antibacterial and Antibiofilm Activities

A Study on the Antipathogenic Effects of Nanoemulsion Against V. parahaemolyticus in Shrimp Aquaculture: Antibacterial and Antibiofilm Activities

In-vitro selection of lactic acid bacteria to combat Salmonella enterica and Campylobacter jejuni in broiler chickens

Campylobacter and Salmonella are the two most prominent foodborne zoonotic pathogens reported in the European Union. As poultry is one of the major sources of these pathogens, it is imperative to mitigate the colonization of these pathogens in poultry. Many strains of lactic acid bacteria (LAB) have demonstrated anti-Salmonella and anti-Campylobacter characteristics to varying degrees and spectrums which are attributed to the production of various metabolites. However, the production of these compounds and consequent antimicrobial properties are highly strain dependent. Therefore, the current study was performed to select a potent LAB and determine its causal attribute in inhibiting Salmonella enterica and Campylobacter jejuni, in-vitro. Six LAB (Lactiplantibacillus plantarum (LP), Lacticaseibacillus casei (LC), Limosilactobacillus reuteri (LR), Lacticaseibacillus rhamnosus (LRh), Leuconostoc mesenteroides (LM) and Pediococcus pentosaceus (PP)) and three serovars of Salmonella enterica (Typhimurium, Enterica and Braenderup) and Campylobacter jejuni were used in the current study. Spot overlays, well diffusion, co-culture and co-aggregation assays against Salmonella and well diffusion assays against Campylobacter jejuni were performed. Organic acid profiling of culture supernatants was performed using HPLC. The results indicated that LRh, LM and PP had the most significant anti-Salmonella effects while LP, LC, LM and PP displayed the most significant anti-Campylobacter effects. Lactic acid and formic acid detected in the culture supernatants seem the most likely source of the anti-Salmonella and anti-Campylobacter effects exhibited by these LAB. In conclusion, Leuconostoc mesenteroides displayed the most significant overall anti-pathogenic effects when compared to the other LAB strains studied, indicating its potential application in-vivo.

Biochemical Approach to Poly(Lactide)-Copper Composite-Impact on Blood Coagulation Processes.

The paper presents the investigation of the biological properties of Poly(Lactide)-Copper composite material obtained by sputter deposition of copper onto Poly(lactide) melt-blown nonwoven fabrics. The functionalized composite material was subjected to microbial activity tests against colonies of Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria, Chaetomium globosum and Candida albicans fungal mold species and biochemical-hematological tests including the evaluation of the Activated Partial Thromboplastin Time, Prothrombin Time, Thrombin Time and electron microscopy fibrin network imaging. The substantial antimicrobial and antifungal activities of the Poly(Lactide)-Copper composite suggests potential applications as an antibacterial/antifungal material. The unmodified Poly(Lactide) fabric showed accelerated human blood plasma clotting in the intrinsic pathway, while copper plating abolished this effect. Unmodified PLA itself could be used for the preparation of wound dressing materials, accelerating coagulation in the case of hemorrhages, and its modifications with the use of various metals might be applied as new customized materials where blood coagulation process could be well controlled, yielding additional anti-pathogen effects.

Akt activator SC79 stimulates antibacterial nitric oxide generation in human nasal epithelial cells in vitro.

The role of Akt in nasal immunity is unstudied. Akt phosphorylates and activates endothelial nitric oxide synthase (eNOS) expressed in epithelial ciliated cells. Nitric oxide (NO) production by ciliated cells can have antibacterial and antiviral effects. Increasing nasal NO may be a useful antipathogen strategy in chronic rhinosinusitis (CRS). We previously showed that small-molecule Akt activator SC79 induces nasal cell NO production and suppresses IL-8 via the transcription factor Nrf-2. We hypothesized that SC79 NO production may additionally have antibacterial effects. NO production was measured using fluorescent dye DAF-FM. We tested effects of SC79 during co-culture of Pseudomonas aeruginosa with primary nasal epithelial cells, using CFU counting and live-dead staining to quantify bacterial killing. Pharmacology determined the mechanism of SC79-induced NO production and tested dependence on Akt. SC79 induced dose-dependent, Akt-dependent NO production in nasal epithelial cells. The NO production required eNOS and Akt. The NO released into the airway surface liquid killed P. aeruginosa. No toxicity (LDH release) or inflammatory effects (IL8 transcription) were observed over 24h. Together, these data suggest multiple immune pathways are stimulated by SC79, with antipathogen effects. This in vitro pilot study suggests that a small-molecule Akt activator may have clinical utility in CRS or respiratory other infection settings, warranting future in vivo studies.

Chitosan and its derivatives as promising plant protection tools.

In modern conditions, the increase in the yield of agricultural crops is provided not by expanding the areas of their cultivation, but mainly by introducing advanced technologies. The most effective strategy for this purpose is the development of genetically resistant and productive cultivars in combination with the use of a variety of plant protection products (PPPs). However, traditional, chemical PPPs, despite their effectiveness, have significant drawbacks, namely, pollution of environment, ecological damage, toxicity to humans. Recently, biological PPPs based on natural compounds have attracted more attention, since they do not have these disadvantages, but at the same time they can be no less effective. One of such agents is chitosan, a deacetylation product of chitin, one of the most common polysaccharides in nature. The high biological activity, biocompatibility, and safety of chitosan determine the breadth and effectiveness of its use in medicine, industry, and agrobiology. The review considers various mechanisms of action of chitosan as a biopesticide, including both a direct inhibitory effect on pathogens and the induction of plant internal defense systems as a result of chitosan binding to cell surface receptors. The effect of chitosan on the formation of resistance to the main classes of pathogens: fungi, bacteria, and viruses has been shown on a variety of plant objects. The review also discusses various ways of using chitosan: for the treatment of seeds, leaves, fruits, soil, as well as its specific biological effects corresponding to these ways. A separate chapter is devoted to protection products based on chitosan, obtained by its chemical modifications, or by means of combining of a certain molecular forms of chitosan with various substances that enhance its antipathogenic effect. The data presented in the review generally give an idea of chitosan and its derivatives as very effective and promising plant protection products and biostimulants.

Silver/Graphene Oxide Nanostructured Coatings for Modulating the Microbial Susceptibility of Fixation Devices Used in Knee Surgery.

Exploring silver-based and carbon-based nanomaterials' excellent intrinsic antipathogenic effects represents an attractive alternative for fabricating anti-infective formulations. Using chemical synthesis protocols, stearate-conjugated silver (Ag@C18) nanoparticles and graphene oxide nanosheets (nGOs) were herein obtained and investigated in terms of composition and microstructure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations revealed the formation of nanomaterials with desirable physical properties, while X-ray diffraction (XRD) analyses confirmed the high purity of synthesized nanomaterials. Further, laser-processed Ag@C18-nGO coatings were developed, optimized, and evaluated in terms of biological and microbiological outcomes. The highly biocompatible Ag@C18-nGO nanostructured coatings proved suitable candidates for the local modulation of biofilm-associated periprosthetic infections.

Exploring the Therapeutic and Nutritional Significance of Bay Laurel (Laurus nobilis) as a Feed Additive in Aquaculture

The exploration of medicinal plants as natural and benign compounds in aquaculture presents a promising alternative to conventional antibiotics and immune prophylactics. In the domain of aquaculture, these plants serve dual roles as both chemotherapeutics and feed additives. Many plants and their derivatives contain an array of bioactive compounds, such as phenolic, polyphenolic, alkaloid, quinone, terpenoid, lectin, and polypeptide compounds, showcasing their effectiveness as alternatives to antibiotics, chemicals, vaccines, and synthetic compounds. Extensive research highlights the positive impact of incorporating herbs into fish diets, contributing to enhanced growth and disease resistance.
 The incorporation of herbs and herbal products into fish diets not only proves cost-effective but also aligns with environmental sustainability, exhibiting minimal side effects on both fish and consumers. Plant extracts are recognized for their diverse benefits, including growth promotion, appetite stimulation, tonicity enhancement, immunostimulation, facilitation of cultured species maturation, and properties such as stress reduction, sexual stimulation, and antipathogenic effects in fish.
 This comprehensive review focuses on the significant role of bay laurel (Laurus nobilis) in aquaculture, serving as a growth promoter, immunostimulant, and antioxidant. Bay laurel emerges as a medicinal herbal plant, offering a viable alternative to antibiotics with a multifaceted impact on aquaculture production and development. The review delves into the mode of action through which bay laurel enhances various aspects of aquaculture, emphasizing its potential as a valuable asset in sustainable and health-conscious fish farming practices. By exploring the diverse bioactive compounds present in bay laurel, this review contributes to a deeper understanding of its applications and implications in the ever-evolving landscape of aquaculture.

Exploration of Variable Solvent Directed Self-Healable Supramolecular M(II)-Metallogels (M = Co, Ni, Zn) of Azelaic Acid: Investigating Temperature-Dependent Ion Conductivity and Antibacterial Efficiency.

Molecular self-assembly assisted self-healing supramolecular metallogels of azelaic acid with cobalt(II)-, nickel(II)-, and zinc(II)-based metal acetate salts were successfully fabricated. Individually, N,N'-dimethylformamide and dimethyl sulfoxide were immobilized within these distinctly synthesized soft-scaffolds of metallogels to attain their semisolid viscoelastic nature. Rheological experiments such as amplitude sweep, frequency sweep, and thixotropic measurements were executed for these metallogels to ratify their gel features. The different extents of supramolecular interactions operating within these solvent-directed metallogels were clearly reflected in terms of their distinct morphological patterns as investigated through field emission scanning electron microscopy. Comparative infrared (IR) spectral properties of metallogels along with individual metal salts and azelaic acid were analyzed. These experimental data clearly depict the significant shifting of Fourier transform (FT)-IR peaks of xerogel samples of different metallogels from the gel-forming precursors. The networks present within the soft-scaffold are evidently illustrated by the electrospray ionization-mass experimental data. The temperature-dependent ionic conductivity studies with these solvent-directed versatile metallogel systems were investigated through impedance spectroscopy. The temperature-dependent impedance spectroscopic studies clearly demonstrate that the ion-transportation within the gel matrix depends not only on the types of cations but also on the dielectric properties of the immobilized solvents. The antipathogenic effect of these metallogel systems has also been explored by testing their effectiveness against human pathogenic Gram-negative bacteria Klebsiella pneumoniae (MTCC 109) and Vibrio parahemolyticus, and Gram-positive bacteria like Bacillus cereus (MTCC 1272). These gel soft-scaffolds show no significant cytotoxicity against both the human neuroblastoma cell line-SH-SY5Y and the human embryonic kidney cell line-HEK 293.

Superomniphobic and Photoactive Surface Presents Antimicrobial Properties by Repelling and Killing Pathogens.

Healthcare-acquired infections place a significant burden on the cost and quality of patient care in hospitals. Reducing contamination on surfaces within healthcare environments is critical for halting the spread of these infections. Herein, we report a bifunctional─repel and kill─surface developed using photoactive TiO2 nanoparticles integrated into a hierarchical scaffold (OmniKill). To quantify the repellency of OmniKill, we developed a touch-based assay, capable of simulating the transfer of individual pathogens, multiple pathogens, or pathogen-latent fecal matter from hands to surfaces. OmniKill repels bacterial pathogens by at least 2.77-log (99.8%). The photoactive material within OmniKill further reduces the viability of transferred pathogens on the surface by an additional 2.43-log (99.6%) after 1 h of light exposure. The antipathogenic effects─repel and kill─remain robust under complex biological contaminates such as feces. These findings show the potential use of OmniKill in reducing the physical transmission of bacterial pathogens in healthcare settings.

Evaluation of Antibiofilm and Antiquorum Sensing Activities of Fucoidan Characterized from Padina boryana against Nosocomial Pathogens.

Modern functional chemicals that can be employed in biotechnology, pharmaceutics, and food science are a sustainable source to be found in seaweeds. The bioactivity of the majority of these marine compounds has received scant research. Fucoidan is a highly sulfated polysaccharide with a range of bioactivities, including an antipathogenic effect. There is still much to learn about the relationship between fucoidan structure and its function in pathogen infections. By employing microwave and probe sonication to create crude fucoidan, DEAE-cellulose anion-exchange chromatography was used to further purify the substance. Purified fucoidan was structurally characterized using UV-Visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and NMR analysis. The results of the structural analysis demonstrate that sulfates and hydroxyl groups are present in the isolated fucoidan. There are fucose residues, according to the NMR data. The present study investigates the bioactivity of fucoidan, a polysaccharide derived from the brown algae Padina boryana, as a potent weapon against the known nosocomial diseases Proteus vulgaris and Salmonella enterica. Fluorescence microscopy was used to show that fucoidan antibiofilm action is totally effective against Proteus vulgaris and Salmonella enterica biofilm formations as well as planktonic cell growths at dosages over 25g/mL. Here, using in vitro investigations of the possible inactivation of molecules that are regulated by acyl-homoserine lactone (AHL) in both bacterial species, we explore the antiquarum sensing and antibiofilm capabilities of fucoidan. According to the present study, extracted fucoidan from Padina boryana can be used to generate antibacterial compounds and operate as a quorum-sensing inhibitor to combat side effects and antibiotic resistance.

Growth assessment of mixed cultures of probiotics and common pathogens

ObjectivesIn this work, an isothermal microcalorimeter was applied to investigate the antipathogenic activity of three probiotics (Lactobacillus acidophilus, Bifidobacterium lactis and Bifidobacterium bifidum) against Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli using the probiotics in mixed culture with the pathogenic microorganisms. MethodsA microcalorimeter was used to monitor the growth of the microorganisms as pure cultures and as co-cultures at 37 °C. Relative growths of the probiotics and pathogenic species were determined after microcalorimetric measurements by serial dilution and plate incubation. Relative growth of mixed cultures of E. coli with L. acidophilus or B. lactis was also determined by traditional plate growth assay for 5.5 h. ResultsThe results showed growth profiles of the microorganisms that were characteristic and showed different lag and peak times for the species. The pathogenic species grew faster than the probiotic species. In the co-cultures, the growth profile of both pathogenic species and probiotics could be identified with the microcalorimeter. Although the pathogenic species grew faster, at the end of the assay, the results showed that the pathogenic species were inhibited in growth by the probiotics as no viable growth of the pathogenic species was detected whereas 107–108 CFU/mL of the probiotics were enumerated after the microcalorimetric assay. Using the traditional plate assay, the data confirmed co-growth of the probiotics and E. coli although cell numbers of E. coli were higher than the probiotics during 5.5 h of co-culture incubation when both were inoculated at 106 CFU/mL. ConclusionThe results demonstrate the antipathogenic effects of probiotics and highlights the potential of microcalorimetry in live mixed culture assays and its limitation.