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Scientific Reports Jun 2023Despite their threatens for Egyptian stone monuments, A few studies focused on using biocontrol agents against deteriorative fungi and bacteria instead of using chemical...
Despite their threatens for Egyptian stone monuments, A few studies focused on using biocontrol agents against deteriorative fungi and bacteria instead of using chemical assays that leave residuals leading to human toxicity and environmental pollution. This work aims to isolate and identify fungal and bacterial isolates that showed deteriorative activities from stone monuments in Temple of Hathor, Luxor, Egypt, as well as determine the inhibitory activity of metabolites produced by Streptomyces exfoliatus SAMAH 2021 against the identified deteriorative fungal and bacterial strains. Moreover, studying the spectral analysis, toxicological assessment of metabolites produced by S. exfoliatus SAMAH 2021 against health human cell fibroblast, and colorimetric measurements on the selected stone monuments. Ten samples were collected from Temple of Hathor, Luxor, Egypt. Three fungal isolates and one bacterial isolate were obtained and identified as A. niger isolate Hathor 2, C. fioriniae strain Hathor 3, P. chrysogenum strain HATHOR 1, and L. sphaericus strain Hathor 4, respectively. Inhibitory potential of the metabolites in all concentrations used (100-25%) against the recommended antibiotics (Tetracycline 10 µg/ml and Doxycycline (30 µg/ml) showed an inhibitory effect toward all tested deteriorative pathogens with a minimum inhibition concentration (MIC) of 25%. Cytotoxicity test confirmed that microbial filtrate as the antimicrobial agent was safe for healthy human skin fibroblast with IC of < 100% and cell viability of 97%. Gas chromatography analysis recorded the existence of thirteen antimicrobial agents, Cis-vaccenic acid; 1,2-Benzenedicarboxylic acid; ç-Butyl-ç-butyrolactone and other compounds. Colorimetric measurements confirmed no color or surface change for the limestone-treated pieces. The use of the metabolite of microbial species antimicrobial as a biocontrol agent raises contemporary issues concerning the bio-protection of the Egyptian monuments to reduce chemical formulas that are toxic to humans and pollute the environment. Such serious problems need further investigation for all kinds of monuments.
Topics: Humans; Egypt; Anti-Infective Agents; Anti-Bacterial Agents; Streptomyces; Microbial Sensitivity Tests
PubMed: 37301893
DOI: 10.1038/s41598-023-36542-1 -
Frontiers in Cellular and Infection... 2023The bulk of bacteria transiently evading appropriate antibiotic regimes and recovered from non-resolutive infections are commonly refer to as persisters. In this... (Review)
Review
The bulk of bacteria transiently evading appropriate antibiotic regimes and recovered from non-resolutive infections are commonly refer to as persisters. In this mini-review, we discuss how antibiotic persisters stem from the interplay between the pathogen and the cellular defenses mechanisms and its underlying heterogeneity.
Topics: Anti-Bacterial Agents; Bacteria
PubMed: 37065203
DOI: 10.3389/fcimb.2023.1141868 -
Brazilian Journal of Biology = Revista... 2023Staphylococcus aureus (S. aureus) is a pathogenic bacteria that causes a variety of potentially fatal infections. The emergence of antibiotic-resistant strains of S.... (Review)
Review
Staphylococcus aureus (S. aureus) is a pathogenic bacteria that causes a variety of potentially fatal infections. The emergence of antibiotic-resistant strains of S. aureus has made treatment even more difficult. In recent years, nanoparticles have been used as an alternative therapeutic agent for S. aureus infections. Among various methods for the synthesis of nanoparticles, the method utilizing plant extracts from different parts of a plant, such as root, stem, leaf, flower, seeds, etc. is gaining widespread usage. Phytochemicals present in plant extract are an inexpensive, eco-friendly, natural material that act as reducing and stabilization agent for the nanoparticle synthesis. The utilization of plant-fabricated nanoparticles against S. aureus is currently in trend. The current review discusses recent findings in the therapeutic application of phytofabricated metal-based nanoparticles against Staphylococcus aureus.
Topics: Staphylococcus aureus; Metal Nanoparticles; Staphylococcal Infections; Plant Leaves; Anti-Bacterial Agents; Plant Extracts; Microbial Sensitivity Tests
PubMed: 36888798
DOI: 10.1590/1519-6984.268052 -
Indian Journal of Pediatrics Jan 2020The first written record of intervention against what later came to be known as an infectious disease was in the early seventeenth century by a Buddhist nun. She dried 3... (Review)
Review
The first written record of intervention against what later came to be known as an infectious disease was in the early seventeenth century by a Buddhist nun. She dried 3 to 4 wk old scabs from patients with mild smallpox and asked well people to inhale the powder. More than a century later in 1796, Edward Jenner described vaccination against smallpox by using cowpox that later was found to be caused by cowpox virus which is non-pathogenic for humans. Another century later in 1890, Robert Koch published the Koch's Postulates allowing the study of pathogenic bacteria and subsequently the study of agents to fight them. The first chemical cure for disease was reported by Paul Erhlich in 1909 in the form of an arsenic compound to treat syphilis. One hundred and ten years since then a lot has happened in the area of preventing and treating infectious diseases with significant contribution to increase in human lifespan. This is the only area of medicine in which treatment (antimicrobial agent) is used to eradicate a replicating biological agent inside the human host. The potential of this second biological agent to mutate under the selection pressure of antibiotics making them resistant was recognized in the 1940s. But the indiscriminate use of antibiotics for over 70 y has led to the present crisis of resistance in major pathogens with increased morbidity and mortality. In this review, we have incorporated all the possible avenues that might be useful in the future. However, none is more important than relearning the judicious use of antibiotics based on microbiology, pharmacology, and genetics.
Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Bacteria; Cowpox; Drug Resistance, Bacterial; Forecasting; History, 18th Century; History, 19th Century; History, 20th Century; History, 21st Century; Humans; Longevity; Smallpox; Syphilis; Vaccination
PubMed: 31713213
DOI: 10.1007/s12098-019-03087-z -
ChemMedChem Jul 2022Carbon dots are small carbon nanoparticles with intrinsic photoluminescence. Because of the advantages such as good biocompatibility and water dispersity, many... (Review)
Review
Carbon dots are small carbon nanoparticles with intrinsic photoluminescence. Because of the advantages such as good biocompatibility and water dispersity, many researchers have applied carbon dots as delivery platforms of antimicrobial agents. Compared with the free small-molecule antimicrobial agents alone, the carbon dot-based systems may exhibit enhanced antimicrobial activity, increased stability, improved cellular uptake, and reduced side effects. This review will mainly discuss the antimicrobial agent-loaded carbon dots for various antibacterial, antifungal, and antiviral applications. The current limitations and future research directions in the related field are also proposed. It is hoped that this review will have implications for the future development of functional carbon dots for various practical antimicrobial uses.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Carbon; Drug Delivery Systems
PubMed: 35429414
DOI: 10.1002/cmdc.202200003 -
International Journal of Nanomedicine 2024Chrysin has a wide range of biological activities, but its poor bioavailability greatly limits its use. Here, we attempted to prepare casein (cas)-based nanoparticles to...
INTRODUCTION
Chrysin has a wide range of biological activities, but its poor bioavailability greatly limits its use. Here, we attempted to prepare casein (cas)-based nanoparticles to promote the biotransfer of chrysin, which demonstrated better bioavailability and anti-infection activity compared to free chrysin.
METHODS
Cas-based chrysin nanoparticles were prepared and characterized, and most of the preparation process was optimized. Then, the in vitro and in vivo release characteristics were studied, and anti-pulmonary infection activity was evaluated.
RESULTS
The constructed chrysin-cas nanoparticles exhibited nearly spherical morphology with particle size and ζ potential of 225.3 nm and -33 mV, respectively. These nanoparticles showed high encapsulation efficiency and drug-loading capacity of 79.84% ± 1.81% and 11.56% ± 0.28%, respectively. In vitro release studies highlighted a significant improvement in the release profile of the chrysin-cas nanoparticles (CCPs). In vivo experiments revealed that the relative oral bioavailability of CCPs was approximately 2.01 times higher than that of the free chrysin suspension. Further investigations indicated that CCPs effectively attenuated pulmonary infections caused by by mitigating oxidative stress and reducing pro-inflammatory cytokines levels, and the efficacy was better than that of the free chrysin suspension.
CONCLUSION
The findings underscore the advantageous bioavailability of CCPs and their protective effects against pulmonary infections. Such advancements position CCPs as a promising pharmaceutical agent and candidate for future therapeutic drug innovations.
Topics: Flavonoids; Caseins; Animals; Nanoparticles; Biological Availability; Particle Size; Mice; Drug Liberation; Male; Oxidative Stress; Anti-Bacterial Agents; Cytokines; Drug Carriers
PubMed: 38895144
DOI: 10.2147/IJN.S457643 -
ACS Applied Materials & Interfaces Oct 2023The choice of the antimicrobial agent and finishing process is very important for the activity, durability, and safety of antimicrobial fabrics. Here, a novel...
The choice of the antimicrobial agent and finishing process is very important for the activity, durability, and safety of antimicrobial fabrics. Here, a novel antimicrobial cotton fabric (HPL-CF) was constructed by covalently bonding an antimicrobial agent, hyperbranched polylysine (HPL), onto the surface of a cotton fabric (CF) pretreated with a silane coupling agent, 3-chloropropyltrimethoxysilane (CPTMS). The multiple amino groups contained in the periphery of HPL make it possible to react with the CF to form multiple bonds, which is beneficial to improve the durability and safety of HPL-CFs. The obtained HPL-CFs exhibited excellent antimicrobial activities against (, Gram-negative bacteria), (, Gram-positive bacteria), and (, fungi) even when the CF was treated with HPL solution at the concentration of 0.5 wt %. HPL-CFs maintained 98, >99, and >99% of antimicrobial ratios for , , and , respectively, after 50 equiv of domestic laundering cycles, surpassing the requirements of the AAA class. The halo method, cell compatibility, and skin irritation assays all prove the fine safety of HPL-CFs. This work demonstrates the great advantages of applying HPL in the antimicrobial finishing of fabrics.
Topics: Polylysine; Cotton Fiber; Escherichia coli; Staphylococcus aureus; Metal Nanoparticles; Anti-Infective Agents; Candida albicans; Anti-Bacterial Agents
PubMed: 37792694
DOI: 10.1021/acsami.3c10587 -
International Journal of Biological... Jul 2023Bio-polymeric based nano-composites and hydrogels are newsworthy nano-biomaterials. Herein, crystalline or fibrous nano-cellulose carboxylate (NCCC and NCCF) were...
Bio-polymeric based nano-composites and hydrogels are newsworthy nano-biomaterials. Herein, crystalline or fibrous nano-cellulose carboxylate (NCCC and NCCF) were selectively prepared via the controllable direct oxidative-hydrolysis of MC in alkaline NaClO at 1:2 mol ratio, 90 °C, and 24 h for NCCC and at 1:1 mol ratio, 70 °C, and 20 h for NCCF. Characterization of NCCC and NCCF were performed by comparative Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and energy dispersive X-ray spectroscopy (EDS). Then, NCCC was cross-linked to the recycled gelatin (Gel) from the medicine capsules and the as-prepared nano-ZnO by maleic anhydride (MA) to give the novel hydrogel Gel/MA/NCCC/nano-ZnO. Nano-ZnO plays multi-roles in this hydrogel preparation, as either catalyst for the esterification of cellulose hydroxyls and amidation of gelatin amino groups or as the anti-bacterial part of hydrogel. The in vitro anti-bacterial activity results against the three gram-negative and gram-positive bacteria by well diffusion method confirmed Gel/MA/NCCC/nano-ZnO as an antibacterial agent with the activity order of P. aeruginosa > S. aureus > E. coli. The top anti-bacterial activity of this hydrogel against the gram-negative resistant bacteria of P. aeruginosa suggests its potential for biomedical applications.
Topics: Hydrogels; Gelatin; Zinc Oxide; Cellulose; Spectroscopy, Fourier Transform Infrared; Staphylococcus aureus; Escherichia coli; Anti-Bacterial Agents; Bacteria; Gram-Negative Bacteria; X-Ray Diffraction; Microbial Sensitivity Tests
PubMed: 37247711
DOI: 10.1016/j.ijbiomac.2023.124922 -
Microbiology Spectrum Apr 2022Bacterial biofilms are difficult to eradicate and can complicate many infections by forming on tissues and medical devices. Phage+antibiotic combinations (PAC) may be...
Bacterial biofilms are difficult to eradicate and can complicate many infections by forming on tissues and medical devices. Phage+antibiotic combinations (PAC) may be more active on biofilms than either type of agent alone, but it is difficult to predict which PAC regimens will be reliably effective. To establish a method for screening PAC combinations against Staphylococcus aureus biofilms, we conducted biofilm time-kill analyses (TKA) using various combinations of phage Sb-1 with clinically relevant antibiotics. We determined the activity of PAC against biofilm versus planktonic bacteria and investigated the emergence of resistance during (24 h) exposure to PAC. As expected, fewer treatment regimens were effective against biofilm than planktonic bacteria. In experiments with isogenic strain pairs, we also saw less activity of PACs against DNS-VISA mutants versus their respective parentals. The most effective treatment against both biofilm and planktonic bacteria was the phage+daptomycin+ceftaroline regimen, which met our stringent definition of bactericidal activity (>3 log CFU/mL reduction). With the VISA-DNS strain 8015 and DNS strain 684, we detected anti-biofilm synergy between Sb-1 and DAP in the phage+daptomycin regimen (>2 log CFU/mL reduction versus best single agent). We did not observe any bacterial resensitization to antibiotics following treatment, but phage resistance was avoided after exposure to PAC regimens for all tested strains. The release of bacterial membrane vesicles tended to be either unaffected or reduced by the various treatment regimens. Interestingly, phage yields from certain biofilm experiments were greater than from similar planktonic experiments, suggesting that Sb-1 might be more efficiently propagated on biofilm. Biofilm-associated multidrug-resistant infections pose significant challenges for antibiotic therapy. The extracellular polymeric matrix of biofilms presents an impediment for antibiotic diffusion, facilitating the emergence of multidrug-resistant populations. Some bacteriophages (phages) can move across the biofilm matrix, degrade it, and support antibiotic penetration. However, little is known about how phages and their hosts interact in the biofilm environment or how different phage+antibiotic combinations (PACs) impact biofilms in comparison to the planktonic state of bacteria, though scattered data suggest that phage+antibiotic synergy occurs more readily under biofilm-like conditions. Our results demonstrated that phage Sb-1 can infect MRSA strains both in biofilm and planktonic states and suggested PAC regimens worthy of further investigation as adjuncts to antibiotics.
Topics: Anti-Bacterial Agents; Bacteriophages; Biofilms; Daptomycin; Methicillin-Resistant Staphylococcus aureus
PubMed: 35348366
DOI: 10.1128/spectrum.00411-22 -
Bioorganic Chemistry May 2021Aminoacyl-tRNA synthetases (aaRSs) are crucial for the correct assembly of amino acids to cognate tRNA to maintain the fidelity of proteosynthesis. AaRSs have become a... (Review)
Review
Aminoacyl-tRNA synthetases (aaRSs) are crucial for the correct assembly of amino acids to cognate tRNA to maintain the fidelity of proteosynthesis. AaRSs have become a hot target in antimicrobial research. Three aaRS inhibitors are already in clinical practice; antibacterial mupirocin inhibits the synthetic site of isoleucyl-tRNA synthetase, antifungal tavaborole inhibits the editing site of leucyl-tRNA synthetase, and antiprotozoal halofuginone inhibits proline-tRNA synthetase. According to the World Health Organization, tuberculosis globally remains the leading cause of death from a single infectious agent. The rising incidence of multidrug-resistant tuberculosis is alarming and urges the search for new antimycobacterial compounds, preferably with yet unexploited mechanism of action. In this literature review, we have covered the up-to-date state in the field of inhibitors of mycobacterial aaRSs. The most studied aaRS in mycobacteria is LeuRS with at least four structural types of inhibitors, followed by TyrRS and AspRS. Inhibitors of MetRS, LysRS, and PheRS were addressed in a single significant study each. In many cases, the enzyme inhibition activity translated into micromolar or submicromolar inhibition of growth of mycobacteria. The most promising aaRS inhibitor as an antimycobacterial compound is GSK656 (compound 8), the only aaRS inhibitor in clinical trials (Phase IIa) for systemic use against tuberculosis. GSK656 is orally available and shares the oxaborole tRNA-trapping mechanism of action with antifungal tavaborole.
Topics: Amino Acyl-tRNA Synthetases; Anti-Bacterial Agents; Bacteria; Dose-Response Relationship, Drug; Enzyme Inhibitors; Humans; Microbial Sensitivity Tests; Molecular Structure; Structure-Activity Relationship
PubMed: 33799176
DOI: 10.1016/j.bioorg.2021.104806