Topic Editors

IBB-Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
IBB—Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisbon, Portugal

Antimicrobial Agents and Nanomaterials

Abstract submission deadline
30 April 2024
Manuscript submission deadline
30 September 2024
Viewed by
41098

Topic Information

Dear Colleagues,

Antimicrobial resistance (AMR) has come to represent a major problem that is attested across healthcare settings worldwide. AMR is caused by multidrug-resistant (MDR) microorganisms, or “superbugs”, which can evade many of the antibiotics used in clinical practice. Today, MDR microorganisms constitute a great clinical and economic burden. In fact, the current methods of clinical treatment have started to rely on more aggressive antibiotic therapy, leading to a decrease in the life quality of the infected patients and an increase in the associated therapeutic costs. Due to the failure of conventional antibiotics, we are now entering a new era of clinical treatment based on compounds. This is reflected, for example, in the development of antibacterial nanomaterials or nanoantibiotics. This Topic collection aims to identify novel strategies that may be used to overcome AMR, with a particular focus on the development of medical nanomaterials. Topics of interest include, but are not limited to, the following:

  • Antimicrobial polymers;
  • Antimicrobial peptides and peptidomimetics;
  • Synergic effects of antimicrobial agents;
  • Antimicrobial coatings;
  • Inhibitors of virulence factors;
  • Drug nanodelivery systems;

We welcome the contributions of authors working in this critical field of research.

Dr. Sandra Pinto
Prof. Dr. Vasco D. B. Bonifácio
Topic Editors

Keywords

  • multidrug resistant bacteria (MDR)
  • resistance mechanisms
  • antibiotics
  • novel antimicrobial agents
  • drug susceptibility

Participating Journals

Journal Name Impact Factor CiteScore Launched Year First Decision (median) APC
Molecules
molecules
4.6 6.7 1996 14.6 Days CHF 2700 Submit
Pharmaceutics
pharmaceutics
5.4 6.9 2009 14.2 Days CHF 2900 Submit
Antibiotics
antibiotics
4.8 5.5 2012 13.7 Days CHF 2900 Submit
Microorganisms
microorganisms
4.5 6.4 2013 15.1 Days CHF 2700 Submit
Biomolecules
biomolecules
5.5 8.3 2011 16.9 Days CHF 2700 Submit
Marine Drugs
marinedrugs
5.4 9.6 2003 14 Days CHF 2900 Submit
Polymers
polymers
5.0 6.6 2009 13.7 Days CHF 2700 Submit
International Journal of Molecular Sciences
ijms
5.6 7.8 2000 16.3 Days CHF 2900 Submit

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Published Papers (27 papers)

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17 pages, 9395 KiB  
Article
Construction Strategy and Mechanism of a Novel Wood Preservative with Excellent Antifungal Effects
by Lei Wang, Teng Wang, Ruidi Hao and Yamei Wang
Molecules 2024, 29(5), 1013; https://doi.org/10.3390/molecules29051013 - 26 Feb 2024
Viewed by 517
Abstract
Wood is a naturally porous material prone to microbial erosion and degradation in outdoor environments. Therefore, the development of an environmentally friendly wood preservative with excellent antibacterial effects and low toxicity is urgently needed. In this study, nitrogen-doped carbon quantum dots (N-CQDs) with [...] Read more.
Wood is a naturally porous material prone to microbial erosion and degradation in outdoor environments. Therefore, the development of an environmentally friendly wood preservative with excellent antibacterial effects and low toxicity is urgently needed. In this study, nitrogen-doped carbon quantum dots (N-CQDs) with excellent antifungal performance and fluorescent properties were synthesized using a one-step hydrothermal method with chitosan quaternary ammonium salt (HACC) as the raw material. The fluorescence characteristics of N-CQD preservatives can help track their position and distribution in wood. The minimum inhibitory concentration (MIC) of N-CQDs is 1.8 mg/mL, which was nearly 22 times lower than that of HACC (40.0 mg/mL) in the PDA medium. The decay resistance test demonstrated that wood treated with N-CQDs showed a considerably reduced decay degree and its mass loss rate decreased from 46 ± 0.5% to 3.8 ± 0.5%. Biological transmission electron microscopy revealed that N-CQDs effectively destroyed fungal cell structures, thereby hindering the growth of Coriolus versicolor. N-CQDs synthesized using the one-step hydrothermal method can be used as an efficient wood preservative that can effectively improve the utilization and service life of wood. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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15 pages, 320 KiB  
Article
In Vitro Antimicrobial Activity of Five Newly Approved Antibiotics against Carbapenemase-Producing Enterobacteria—A Pilot Study in Bulgaria
by Rumyana Markovska, Petya Stankova, Temenuga Stoeva, Emma Keuleyan, Kalina Mihova and Lyudmila Boyanova
Antibiotics 2024, 13(1), 81; https://doi.org/10.3390/antibiotics13010081 - 15 Jan 2024
Viewed by 1141
Abstract
To solve the problem with pan-drug resistant and extensively drug-resistant Gram-negative microbes, newly approved drugs such as ceftazidime/avibactam, cefiderocol, plazomicin, meropenem/vaborbactam, and eravacycline have been introduced in practice. The aim of the present study was to collect carbapenemase-producing clinical Enterobacterales isolates, to characterize [...] Read more.
To solve the problem with pan-drug resistant and extensively drug-resistant Gram-negative microbes, newly approved drugs such as ceftazidime/avibactam, cefiderocol, plazomicin, meropenem/vaborbactam, and eravacycline have been introduced in practice. The aim of the present study was to collect carbapenemase-producing clinical Enterobacterales isolates, to characterize their carbapenemase genes and clonal relatedness, and to detect their susceptibility to commonly used antimicrobials and the above-mentioned newly approved antibiotics. Sixty-four carbapenemase producers were collected in a period of one year from four Bulgarian hospitals, mainly including Klebsiella pneumoniae (89% of the isolates) and also single Proteus mirabilis, Providencia stuartii and Citrobacter freundii isolates. The main genotype was blaNDM-1 (in 61%), followed by blaKPC-2 (23%), blaVIM-1 (7.8%) and blaOXA-48 (7.8%). Many isolates showed the presence of ESBL (blaCTX-M-15/-3 in 76.6%) and AmpC (blaCMY-4 in 37.5% or blaCMY-99 in 7.8% of isolates). The most common MLST type was K. pneumoniae ST11 (57.8%), followed by ST340 (12.5%), ST258 (6.3%) and ST101 (6.3%). The isolates were highly resistant to standard-group antibiotics, except they were susceptible to tigecycline (83.1%), colistin (79.7%), fosfomycin (32.8%), and aminoglycosides (20.3–35.9%). Among the newly approved compounds, plazomicin (90.6%) and eravacycline (76.3%) showed the best activity. Susceptibility to ceftazidime/avibactam and meropenem/vaborbactam was 34.4% and 27.6%, respectively. For cefiderocol, a large discrepancy was observed between the percentages of susceptible isolates according to EUCAST susceptibility breakpoints (37.5%) and those of CLSI (71.8%), detected by the disk diffusion method. This study is the first report to show patterns of susceptibility to five newly approved antibiotics among molecularly characterized isolates in Bulgaria. The data may contribute to both the improvement of treatment of individual patients and the choice of infection control strategy and antibiotic policy. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
15 pages, 7183 KiB  
Article
Exploring PLGA-OH-CATH30 Microspheres for Oral Therapy of Escherichia coli-Induced Enteritis
by Xiaoqian Jiao, Bin Liu, Xufeng Dong, Shubai Wang, Xiulei Cai, Hongliang Zhang and Zhihua Qin
Biomolecules 2024, 14(1), 86; https://doi.org/10.3390/biom14010086 - 10 Jan 2024
Viewed by 1015
Abstract
Antibiotic therapy effectively addresses Escherichia coli-induced enteric diseases, but its excessive utilization results in microbial imbalance and heightened resistance. This study evaluates the therapeutic efficacy of orally administered poly (lactic-co-glycolic acid) (PLGA)-loaded antimicrobial peptide OH-CATH30 microspheres in murine bacterial enteritis. Mice were [...] Read more.
Antibiotic therapy effectively addresses Escherichia coli-induced enteric diseases, but its excessive utilization results in microbial imbalance and heightened resistance. This study evaluates the therapeutic efficacy of orally administered poly (lactic-co-glycolic acid) (PLGA)-loaded antimicrobial peptide OH-CATH30 microspheres in murine bacterial enteritis. Mice were categorized into the healthy control group (CG), untreated model group (MG), OH-CATH30 treatment group (OC), PLGA-OH-CATH30 treatment group (POC), and gentamicin sulfate treatment group (GS). Except for the control group, all other experimental groups underwent Escherichia coli-induced enteritis, followed by a 5-day treatment period. The evaluation encompassed clinical symptoms, intestinal morphology, blood parameters, inflammatory response, and gut microbiota. PLGA-OH-CATH30 microspheres significantly alleviated weight loss and intestinal damage while also reducing the infection-induced increase in spleen index. Furthermore, these microspheres normalized white blood cell count and neutrophil ratio, suppressed inflammatory factors (IL-1β, IL-6, and TNF-α), and elevated the anti-inflammatory factor IL-10. Analysis of 16S rRNA sequencing results demonstrated that microsphere treatment increased the abundance of beneficial bacteria, including Phocaeicola vulgatus, in the intestinal tract while concurrently decreasing the abundance of pathogenic bacteria, such as Escherichia. In conclusion, PLGA-OH-CATH30 microspheres have the potential to ameliorate intestinal damage and modulate the intestinal microbiota, making them a promising alternative to antibiotics for treating enteric diseases induced by Escherichia coli. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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21 pages, 2326 KiB  
Article
Novel BRICHOS-Related Antimicrobial Peptides from the Marine Worm Heteromastus filiformis: Transcriptome Mining, Synthesis, Biological Activities, and Therapeutic Potential
by Pavel V. Panteleev, Victoria N. Safronova, Shuting Duan, Alexey S. Komlev, Ilia A. Bolosov, Roman N. Kruglikov, Tatiana I. Kombarova, Olga V. Korobova, Eugenia S. Pereskokova, Alexander I. Borzilov, Igor A. Dyachenko, Olga V. Shamova, Yu Huang, Qiong Shi and Tatiana V. Ovchinnikova
Mar. Drugs 2023, 21(12), 639; https://doi.org/10.3390/md21120639 - 14 Dec 2023
Viewed by 1471
Abstract
Marine polychaetes represent an extremely rich and underexplored source of novel families of antimicrobial peptides (AMPs). The rapid development of next generation sequencing technologies and modern bioinformatics approaches allows us to apply them for characterization of AMP-derived genes and the identification of encoded [...] Read more.
Marine polychaetes represent an extremely rich and underexplored source of novel families of antimicrobial peptides (AMPs). The rapid development of next generation sequencing technologies and modern bioinformatics approaches allows us to apply them for characterization of AMP-derived genes and the identification of encoded immune-related peptides with the aid of genome and transcriptome mining. Here, we describe a universal bioinformatic approach based on the conserved BRICHOS domain as a search query for the identification of novel structurally unique AMP families in annelids. In this paper, we report the discovery of 13 novel BRICHOS-related peptides, ranging from 18 to 91 amino acid residues in length, in the cosmopolitan marine worm Heteromastus filiformis with the assistance of transcriptome mining. Two characteristic peptides with a low homology in relation to known AMPs—the α-helical amphiphilic linear peptide, consisting of 28 amino acid residues and designated as HfBRI-28, and the 25-mer β-hairpin peptide, specified as HfBRI-25 and having a unique structure stabilized by two disulfide bonds—were obtained and analyzed as potential antimicrobials. Interestingly, both peptides showed the ability to kill bacteria via membrane damage, but mechanisms of their action and spectra of their activity differed significantly. Being non-cytotoxic towards mammalian cells and stable to proteolysis in the blood serum, HfBRI-25 was selected for further in vivo studies in a lethal murine model of the Escherichia coli infection, where the peptide contributed to the 100% survival rate in animals. A high activity against uropathogenic strains of E. coli (UPEC) as well as a strong ability to kill bacteria within biofilms allow us to consider the novel peptide HfBRI-25 as a promising candidate for the clinical therapy of urinary tract infections (UTI) associated with UPEC. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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19 pages, 11638 KiB  
Article
Improving the Antibacterial Properties of Dental Bonding Materials Loaded with Silver Compounds
by Elena Ferrando-Magraner, Verónica García-Sanz, Carlos Bellot-Arcís, Anna Marín-Gozalbo, Luís Cabedo-Mas, Gladys Mínguez-Vega and Vanessa Paredes-Gallardo
Antibiotics 2023, 12(12), 1721; https://doi.org/10.3390/antibiotics12121721 - 13 Dec 2023
Viewed by 957
Abstract
Biofilm accumulation, the appearance of white spot lesions and the development of secondary caries are the main complications in orthodontic patients. A promising approach to fight this situation is the development of adhesive cements with improved antibacterial properties. The aim of the present [...] Read more.
Biofilm accumulation, the appearance of white spot lesions and the development of secondary caries are the main complications in orthodontic patients. A promising approach to fight this situation is the development of adhesive cements with improved antibacterial properties. The aim of the present study was to evaluate the possibility of improving the antibacterial properties of glass ionomer cements by incorporating different types of antimicrobial compounds without altering their physical and mechanical properties. Different concentrations of silver carbonate (SC) and an inorganic glass with encapsulated silver were added to the glass ionomer cement, as well as chitosan, to achieve synergistic antibacterial activity. Variations in the antibacterial capacity were evaluated using the agar diffusion test; the potential alteration of the physical and mechanical properties of the material was analyzed by the shear bond strength test. SEM characterization and colorimetric evaluation were also conducted. Samples of SC up to 1% and inorganic glass with encapsulated silver up to 5% showed significant improvement in their antibacterial ability without compromising shear strength. The highest antimicrobial activity was observed for Lactobacillus acidophilus, with inhibition zones of 3.8 and 3.1 mm for SC and inorganic glass, respectively. The characterization of the samples did not detect any major structural changes between the different samples. The only group that underwent a noticeable color change was the group with SC. The results show that the incorporation of silver carbonate and inorganic glass with encapsulated silver provided the glass ionomer cement with an antibacterial capacity without compromising the bond strength and without modifying the structure of the material. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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24 pages, 10686 KiB  
Article
Naphthyl-Substituted Indole and Pyrrole Carboxylic Acids as Effective Antibiotic Potentiators—Inhibitors of Bacterial Cystathionine γ-Lyase
by Andrey S. Kuzovlev, Mikhail D. Zybalov, Andrey V. Golovin, Maxim A. Gureev, Mariia A. Kasatkina, Mikhail V. Biryukov, Albina R. Belik, Sergey A. Silonov, Maxim A. Yunin, Nailya A. Zigangirova, Vasiliy V. Reshetnikov, Yulia E. Isakova, Yuri B. Porozov and Roman A. Ivanov
Int. J. Mol. Sci. 2023, 24(22), 16331; https://doi.org/10.3390/ijms242216331 - 15 Nov 2023
Cited by 1 | Viewed by 1256
Abstract
Over the past decades, the problem of bacterial resistance to most antibiotics has become a serious threat to patients’ survival. Nevertheless, antibiotics of a novel class have not been approved since the 1980s. The development of antibiotic potentiators is an appealing alternative to [...] Read more.
Over the past decades, the problem of bacterial resistance to most antibiotics has become a serious threat to patients’ survival. Nevertheless, antibiotics of a novel class have not been approved since the 1980s. The development of antibiotic potentiators is an appealing alternative to the challenging process of searching for new antimicrobials. Production of H2S—one of the leading defense mechanisms crucial for bacterial survival—can be influenced by the inhibition of relevant enzymes: bacterial cystathionine γ-lyase (bCSE), bacterial cystathionine β-synthase (bCBS), or 3-mercaptopyruvate sulfurtransferase (MST). The first one makes the main contribution to H2S generation. Herein, we present data on the synthesis, in silico analyses, and enzymatic and microbiological assays of novel bCSE inhibitors. Combined molecular docking and molecular dynamics analyses revealed a novel binding mode of these ligands to bCSE. Lead compound 2a manifested strong potentiating activity when applied in combination with some commonly used antibiotics against multidrug-resistant Acinetobacter baumannii, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus. The compound was found to have favorable in vitro absorption, distribution, metabolism, excretion, and toxicity parameters. The high effectiveness and safety of compound 2a makes it a promising candidate for enhancing the activity of antibiotics against high-priority pathogens. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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28 pages, 12637 KiB  
Article
Genome-Wide Identification of Trachinotus ovatus Antimicrobial Peptides and Their Immune Response against Two Pathogen Challenges
by Yu Liang, Jin-Min Pan, Ke-Cheng Zhu, Lin Xian, Hua-Yang Guo, Bao-Suo Liu, Nan Zhang, Jing-Wen Yang and Dian-Chang Zhang
Mar. Drugs 2023, 21(10), 505; https://doi.org/10.3390/md21100505 - 25 Sep 2023
Cited by 2 | Viewed by 1388
Abstract
Golden pompano, Trachinotus ovatus, as a highly nutritious commercially valuable marine fish, has become one of the preferred species for many fish farmers due to its rapid growth, wide adaptability, and ease of feeding and management. However, with the expansion of aquaculture [...] Read more.
Golden pompano, Trachinotus ovatus, as a highly nutritious commercially valuable marine fish, has become one of the preferred species for many fish farmers due to its rapid growth, wide adaptability, and ease of feeding and management. However, with the expansion of aquaculture scale, bacterial and parasitic diseases have also become major threats to the golden pompano industry. This study, based on comparative genomics, shows the possibility of preferential evolution of freshwater fish over marine fish by analyzing the phylogenetic relationships and divergence times of 14 marine fish and freshwater fish. Furthermore, we identified antimicrobial peptide genes from 14 species at the genomic level and found that the number of putative antimicrobial peptides may be related to species evolution. Subsequently, we classified the 341 identified AMPs from golden pompano into 38 categories based on the classification provided by the APD3. Among them, TCP represented the highest proportion, accounting for 23.2% of the total, followed by scolopendin, lectin, chemokine, BPTI, and histone-derived peptides. At the same time, the distribution of AMPs in chromosomes varied with type, and covariance analysis showed the frequency of its repeat events. Enrichment analysis and PPI indicated that AMP was mainly concentrated in pathways associated with disease immunity. In addition, our transcriptomic data measured the expression of putative AMPs of golden pompano in 12 normal tissues, as well as in the liver, spleen, and kidney infected with Streptococcus agalactiae and skin infected with Cryptocaryon irritans. As the infection with S. agalactiae and C. irritans progressed, we observed tissue specificity in the number and types of responsive AMPs. Positive selection of AMP genes may participate in the immune response through the MAPK signaling pathway. The genome-wide identification of antimicrobial peptides in the golden pompano provided a complete database of potential AMPs that can contribute to further understanding the immune mechanisms in pathogens. AMPs were expected to replace traditional antibiotics and be developed into targeted drugs against specific bacterial and parasitic pathogens for more precise and effective treatment to improve aquaculture production. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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16 pages, 1538 KiB  
Article
Study of the Antimicrobial Potential of the Arthrospira platensis, Planktothrix agardhii, Leptolyngbya cf. ectocarpi, Roholtiella mixta nov., Tetraselmis viridis, and Nanofrustulum shiloi against Gram-Positive, Gram-Negative Bacteria, and Mycobacteria
by Alexander Lykov, Alexei Salmin, Ruslan Gevorgiz, Svetlana Zheleznova, Lyubov Rachkovskaya, Maria Surovtseva and Olga Poveshchenko
Mar. Drugs 2023, 21(9), 492; https://doi.org/10.3390/md21090492 - 14 Sep 2023
Cited by 1 | Viewed by 1209
Abstract
The incidence of diseases brought on by resistant strains of micro-organisms, including tuberculosis, is rising globally as a result of the rapid rise in pathogenic micro-organism resistance to antimicrobial treatments. Secondary metabolites with potential for antibacterial activity are produced by cyanobacteria and microalgae. [...] Read more.
The incidence of diseases brought on by resistant strains of micro-organisms, including tuberculosis, is rising globally as a result of the rapid rise in pathogenic micro-organism resistance to antimicrobial treatments. Secondary metabolites with potential for antibacterial activity are produced by cyanobacteria and microalgae. In this study, gram-positive (S. aureus, E. faecalis) and gram-negative (K. pneumoniae, A. baumannii, P. aeruginosa) bacteria were isolated from pulmonary tuberculosis patients receiving long-term antituberculosis therapy. The antimicrobial potential of extracts from the cyanobacteria Leptolyngbya cf. ectocarpi, Planktothrix agardhii, Arthrospira platensis, Rohotiella mixta sp. nov., Nanofrustulum shiloi, and Tetraselmis (Platymonas) viridis Rouchijajnen was evaluated. On mouse splenocytes and peritoneal macrophages, extracts of cyanobacteria and microalgae had inhibitory effects. In vitro studies have shown that cyanobacteria and microalgae extracts suppress the growth of bacteria and mycobacteria. At the same time, it has been demonstrated that cyanobacterial and microalgal extracts can encourage bacterial growth in a test tube. Additionally, the enhanced fucoxanthin fraction significantly reduced the development of bacteria in vitro. In a mouse experiment to simulate tuberculosis, the mycobacterial load in internal organs was considerably decreased by fucoxanthin. According to the information gathered, cyanobacteria and microalgae are potential sources of antibacterial compounds that can be used in the manufacturing of pharmaceutical raw materials. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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16 pages, 4897 KiB  
Article
Antimicrobial Activity and Toxicity of Newly Synthesized 4-[4-(benzylamino)butoxy]-9H-carbazole Derivatives
by Katarzyna Niedziałkowska, Aleksandra Felczak, Iwona E. Głowacka, Dorota G. Piotrowska and Katarzyna Lisowska
Int. J. Mol. Sci. 2023, 24(18), 13722; https://doi.org/10.3390/ijms241813722 - 06 Sep 2023
Viewed by 665
Abstract
One of the main challenges of medicinal chemistry is the search for new substances with antimicrobial potential that could be used in the fight against pathogenic microorganisms. Therefore, the antimicrobial activity of newly synthesized compounds is still being investigated. Carbazole-containing compounds appear to [...] Read more.
One of the main challenges of medicinal chemistry is the search for new substances with antimicrobial potential that could be used in the fight against pathogenic microorganisms. Therefore, the antimicrobial activity of newly synthesized compounds is still being investigated. Carbazole-containing compounds appear to be promising antibacterial, antifungal, and antiviral agents. The aim of this study was to examine the antimicrobial potential and toxicity of newly synthesized isomeric fluorinated 4-[4-(benzylamino)butoxy]-9H-carbazole derivatives. Their antimicrobial activity against bacteria and fungi was tested according to CLSI guidelines. Similarly to previously studied carbazole-containing compounds, the tested derivatives showed the ability to effectively inhibit the growth of Gram-positive bacteria. The addition of carbazole derivatives 2, 4, and 8 at the concentration of 16 µg/mL caused the inhibition of S. aureus growth by over 60%. The MIC value of compounds 25 and 710 was 32 µg/mL for Staphylococcus strains. Gram-negative strains of E. coli and P. aeruginosa were found to be more resistant to the tested carbazole derivatives. E. coli cells treated with compounds 3 and 8 at a concentration of 64 µg/mL resulted in a greater-than-40% reduction in bacterial growth. In the case of the P. aeruginosa strain, all compounds in the highest concentration that we tested limited growth by 35–42%. Moreover, an over-60% inhibition of fungal growth was observed in the cultures of C. albicans and A. flavus incubated with 64 µg/mL of compounds 2 or 7 and 1 or 4, respectively. The hemolysis of red blood cells after their incubation with the tested carbazole derivatives was in the range of 2–13%. In the case of human fibroblast cells, the toxicity of the tested compounds was higher. Derivative 1, functionalized with fluorine in position 2 and its hydrobromide, was the least toxic. The obtained results indicated the antimicrobial potential of the tested 4-[4-(benzylamino)butoxy]-9H-carbazole derivatives, especially against S. aureus strains; therefore, it is worth further modifying these structures, in order to enhance their activity against pathogenic microorganisms. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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21 pages, 3540 KiB  
Review
Engineered Biomaterials Trigger Remineralization and Antimicrobial Effects for Dental Caries Restoration
by Yuexiao Li, Minda Liu, Mingyu Xue, Yuanyuan Kang, Dongjuan Liu, Yan Wen, Duoyi Zhao and Boyu Guan
Molecules 2023, 28(17), 6373; https://doi.org/10.3390/molecules28176373 - 31 Aug 2023
Cited by 1 | Viewed by 2084
Abstract
Dental caries is the most prevalent chronic disease globally, significantly impacting individuals’ quality of life. A key reason behind the failure of implanted restorations is their biological inactivity, meaning they are unable to form crosslinks with the surrounding tooth structures, thus making patients [...] Read more.
Dental caries is the most prevalent chronic disease globally, significantly impacting individuals’ quality of life. A key reason behind the failure of implanted restorations is their biological inactivity, meaning they are unable to form crosslinks with the surrounding tooth structures, thus making patients susceptible to implant loss and recurrent tooth decay. For the treatment of caries, antibacterial medicine and remineralization are effective means of treating the recurrence of caries. Owing to the rapid progression in the biomaterials field, several biomaterials have been reported to display antimicrobial properties and aid in dentin remineralization. Bioactive materials hold considerable potential in diminishing biofilm accumulation, inhibiting the process of demineralization, enabling dentin remineralization, and combating bacteria related to caries. Bioactive materials, such as fluoride, amorphous calcium phosphate, bioactive glass, collagen, and resin-based materials, have demonstrated their effectiveness in promoting dentin remineralization and exerting antibacterial effects on dental caries. However, the concentration of fluoride needs to be strictly controlled. Although amorphous calcium phosphate can provide the necessary calcium and phosphorus ions for remineralization, it falls short in delivering the mechanical strength required for oral mastication. Resin-based materials also offer different advantages due to the complexity of their design. In this review, we delve into the application of advanced bioactive materials for enhancing dentin remineralization and antibacterial properties. We eagerly anticipate future developments in bioactive materials for the treatment of dental caries. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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17 pages, 3864 KiB  
Article
Application of Three Compounds Extracted from Cynodon dactylon against Streptococcus mutans Biofilm Formation to Prevent Oral Diseases
by Tasnia Habib, Aminur Rahman, Anroop B. Nair and S. M. Shahinul Islam
Biomolecules 2023, 13(9), 1292; https://doi.org/10.3390/biom13091292 - 24 Aug 2023
Viewed by 1289
Abstract
Streptococcus mutans bacteria form a biofilm called plaque that causes oral diseases, including tooth decay. Therefore, inhibition of biofilm formation is essential to maintaining good oral health. The health and nutritional benefits of Cynodon dactylon are well documented, but very little is known [...] Read more.
Streptococcus mutans bacteria form a biofilm called plaque that causes oral diseases, including tooth decay. Therefore, inhibition of biofilm formation is essential to maintaining good oral health. The health and nutritional benefits of Cynodon dactylon are well documented, but very little is known about its use to treat against oral diseases. The aim of this study was to detect the adhesion strength of the S. mutans bacterial biofilm in 100 cases in the Rajshahi region and evaluate the inhibitory activity of different compound extracts of C. dactylon on the S. mutans bacterial biofilm by determining the composition of isolated compounds using phytochemical analysis. Nuclear magnetic resonance (NMR) spectroscopy confirmed that three specific compounds from C. dactylon were discovered in this study: 3,7,11,15 tetramethyl hexadec-2-4dien 1-o1, compound 3,7,11,15 tetramethylhexadec-2-en-1-o1 from phytol derivatives, and stigmasterol. Results indicated that the compound of 3,7,11,15-tetramethyl-hexadec-2-en-1-ol exhibited higher antibiofilm activities on S. mutans than those of the other compound extracts. A lower level of minimum inhibitory concentration was exposed by 3, 7, 11,15 tetramethyl hexadeca-2-en-1-o1 (T2) on S. mutans at 12.5 mL. In this case, the compound of 3,7,11,15 tetramethyl hexadec 2en-1-o1 was used, and patients showed a mean value and standard error reduced from 3.42 ± 0.21 to 0.33 ± 0.06 nm. The maximum inhibition was (80.10%) in the case of patient no. 17, with a value of p < 0.05 found for S. mutans to which 12.5 μL/mL ethyl acetate extract was applied. From these findings, it may be concluded that C. dactylon extracts can be incorporated into various oral preparations to prevent tooth decay. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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12 pages, 1306 KiB  
Review
Aurachins, Bacterial Antibiotics Interfering with Electron Transport Processes
by Sebastian Kruth and Markus Nett
Antibiotics 2023, 12(6), 1067; https://doi.org/10.3390/antibiotics12061067 - 17 Jun 2023
Viewed by 1523
Abstract
Aurachins are farnesylated quinolone alkaloids of bacterial origin and excellent inhibitors of the respiratory chain in pro- and eukaryotes. Therefore, they have become important tool compounds for the investigation of electron transport processes and they also serve as lead structures for the development [...] Read more.
Aurachins are farnesylated quinolone alkaloids of bacterial origin and excellent inhibitors of the respiratory chain in pro- and eukaryotes. Therefore, they have become important tool compounds for the investigation of electron transport processes and they also serve as lead structures for the development of antibacterial and antiprotozoal drugs. Especially aurachin D proved to be a valuable starting point for structure-activity relationship studies. Aurachin D is a selective inhibitor of the cytochrome bd oxidase, which has received increasing attention as a target for the treatment of infectious diseases caused by mycobacteria. Moreover, aurachin D possesses remarkable activities against Leishmania donovani, the causative agent of leishmaniasis. Aurachins are naturally produced by myxobacteria of the genus Stigmatella as well as by some Streptomyces and Rhodococcus strains. The recombinant production of these antibiotics turned out to be challenging due to their complex biosynthesis and their inherent toxicity. Recently, the biotechnological production of aurachin D was established in E. coli with a titer which is higher than previously reported from natural producer organisms. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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19 pages, 3421 KiB  
Review
Extracellular Vesicles and Infection: From Hijacked Machinery to Therapeutic Tools
by Diogo Gonçalves, Sandra N. Pinto and Fábio Fernandes
Pharmaceutics 2023, 15(6), 1738; https://doi.org/10.3390/pharmaceutics15061738 - 15 Jun 2023
Viewed by 1465
Abstract
Extracellular vesicles (EVs) comprise a broad range of secreted cell-derived membrane vesicles. Beyond their more well-characterized role in cell communication, in recent years, EVs have also been shown to play important roles during infection. Viruses can hijack the biogenesis of exosomes (which are [...] Read more.
Extracellular vesicles (EVs) comprise a broad range of secreted cell-derived membrane vesicles. Beyond their more well-characterized role in cell communication, in recent years, EVs have also been shown to play important roles during infection. Viruses can hijack the biogenesis of exosomes (which are small EVs) to promote viral spreading. Additionally, these exosomes are also important mediators in inflammation and immune responses during both bacterial and viral infections. This review summarizes these mechanisms while also describing the impact of bacterial EVs in regulating immune responses. Finally, the review also focuses on the potential and challenges of using EVs, in particular, to tackle infectious diseases. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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18 pages, 6980 KiB  
Article
Antibacterial and Cytotoxic Effects of Biosynthesized Zinc Oxide and Titanium Dioxide Nanoparticles
by Samrin Habib, Farzana Rashid, Hunaiza Tahir, Iram Liaqat, Asma Abdul Latif, Sajida Naseem, Awais Khalid, Nazima Haider, Umme Hani, Rehab A. Dawoud, Yosra Modafer, Asia Bibi and Ohoud A. Jefri
Microorganisms 2023, 11(6), 1363; https://doi.org/10.3390/microorganisms11061363 - 23 May 2023
Cited by 6 | Viewed by 1574
Abstract
Nanotechnology is a rapidly developing field of research that studies materials having dimensions of less than 100 nanometers. It is applicable in many areas of life sciences and medicine including skin care and personal hygiene, as these materials are the essential components of [...] Read more.
Nanotechnology is a rapidly developing field of research that studies materials having dimensions of less than 100 nanometers. It is applicable in many areas of life sciences and medicine including skin care and personal hygiene, as these materials are the essential components of various cosmetics and sunscreens. The aim of the present study was to synthesize Zinc oxide (ZnO) and Titanium dioxide (TiO2) nanoparticles (NPs) by using Calotropis procera (C. procera) leaf extract. Green synthesized NPs were characterized by UV spectroscopy, Fourier transform infrared (FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM) to investigate their structure, size, and physical properties. The antibacterial and synergistic effects of ZnO and TiO2 NPs along with antibiotics were also observed against bacterial isolates. The antioxidant activity of synthesized NPs was analyzed by their α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity. In vivo toxic effects of the synthesized NPs were evaluated in albino mice at different doses (100, 200, and 300 mg/kg body weight) of ZnO and TiO2 NPs administered orally for 7, 14, and 21 days. The antibacterial results showed that the zone of inhibition (ZOI) was increased in a concentration-dependent manner. Among the bacterial strains, Staphylococcus aureus showed the highest ZOI, i.e., 17 and 14 mm against ZnO and TiO2 NPs, respectively, while Escherichia coli showed the lowest ZOI, i.e., 12 and 10 mm, respectively. Therefore, ZnO NPs are potent antibacterial agents compared to TiO2 NPs. Both NPs showed synergistic effects with antibiotics (ciprofloxacin and imipenem). Moreover, the DPPH activity showed that ZnO and TiO2 NPs have significantly (p > 0.05) higher antioxidant activity, i.e., 53% and 58.7%, respectively, which indicated that TiO2 has good antioxidant potential compared to ZnO NPs. However, the histological changes after exposure to different doses of ZnO and TiO2 NPs showed toxicity-related changes in the structure of the kidney compared to the control group. The current study provided valuable information about the antibacterial, antioxidant, and toxicity impacts of green synthesized ZnO and TiO2 NPs, which can be influential in the further study of their eco-toxicological effects. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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17 pages, 739 KiB  
Review
Combating Microbial Infections Using Metal-Based Nanoparticles as Potential Therapeutic Alternatives
by Rajwinder Kaur, Kirandeep Kaur, Mohammad H. Alyami, Damanpreet Kaur Lang, Balraj Saini, Mohammad F. Bayan and Balakumar Chandrasekaran
Antibiotics 2023, 12(5), 909; https://doi.org/10.3390/antibiotics12050909 - 15 May 2023
Cited by 4 | Viewed by 1805
Abstract
The nature of microorganisms and the efficiency of antimicrobials have witnessed a huge co-dependent change in their dynamics over the last few decades. On the other side, metals and metallic compounds have gained popularity owing to their effectiveness against various microbial strains. A [...] Read more.
The nature of microorganisms and the efficiency of antimicrobials have witnessed a huge co-dependent change in their dynamics over the last few decades. On the other side, metals and metallic compounds have gained popularity owing to their effectiveness against various microbial strains. A structured search of both research and review papers was conducted via different electronic databases, such as PubMed, Bentham, Springer, and Science Direct, among others, for the present review. Along with these, marketed products, patents, and Clinicaltrials.gov were also referred to for our review. Different microbes such as bacteria, fungi, etc., and their diverse species and strains have been reviewed and found to be sensitive to metal-carrying formulations. The products are observed to restrict growth, multiplication, and biofilm formation effectively and adequately. Silver has an apt use in this area of treatment and recovery, and other metals like copper, gold, iron, and gallium have also been observed to generate antimicrobial activity. The present review identified membrane disruption, oxidative stress, and interaction with proteins and enzymes to be the primary microbicidal processes. Elaborating the action, nanoparticles and nanosystems are shown to work in our favor in well excelled and rational ways. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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12 pages, 1328 KiB  
Article
Compounds That Have an Anti-Biofilm Effect against Common Bacteria at Very Low Concentrations and Their Antibiotic Combination Effect
by Hyeon-Ji Hwang, Dan-dan Li, Jieun Lee, Min Kyung Kang, Hyung Ryong Moon and Joon-Hee Lee
Antibiotics 2023, 12(5), 853; https://doi.org/10.3390/antibiotics12050853 - 05 May 2023
Cited by 2 | Viewed by 1271
Abstract
Two synthetic compounds, MHY1383, azo-resveratrol and MHY1387, 5-[4-hydroxy-3,5-methoxybenzy]-2-thioxodihydropyrimidine-4,6[1H,5H]-dione have been reported to have an anti-biofilm effect on Pseudomonas aeruginosa at very low concentrations (1–10 pM). Here, we investigated the anti-biofilm effects of these compounds in various bacteria. We found that MHY1383 significantly inhibited [...] Read more.
Two synthetic compounds, MHY1383, azo-resveratrol and MHY1387, 5-[4-hydroxy-3,5-methoxybenzy]-2-thioxodihydropyrimidine-4,6[1H,5H]-dione have been reported to have an anti-biofilm effect on Pseudomonas aeruginosa at very low concentrations (1–10 pM). Here, we investigated the anti-biofilm effects of these compounds in various bacteria. We found that MHY1383 significantly inhibited Escherichia coli, Bacillus subtilis, and Staphylococcus aureus biofilm formation at 1 pM, 1 nM, and 10 nM, respectively. MHY1387 also inhibited the biofilm formation of E. coli, B. subtilis, and S. aureus at 1 pM, 10 nM, and 100 pM, respectively. Both MHY1383 and MHY1387 showed medium-dependent anti-biofilm effects on Salmonella enterica at high concentrations (10 μM). We also tested the susceptibility to antibiotics by measuring the minimum inhibitory concentration (MIC) in various bacteria. When P. aeruginosa, E. coli, B. subtilis, S. enterica, and S. aureus were treated with MHY1383 or MHY1387 in combination with four different antibiotics, the MICs of carbenicillin against B. subtilis and S. aureus were lowered more than two-fold by the combination with MHY1387. However, in all other combinations, the MIC changed within two-fold. The results of this study suggest that MHY1383 and MHY1387 are effective anti-biofilm agents and can be used at very low concentrations against biofilms formed by various types of bacteria. We also suggest that even if a substance that inhibits biofilm is used together with antibiotics, it does not necessarily have the effect of lowering the MIC of the antibiotics. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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11 pages, 2343 KiB  
Article
The Antimicrobial Effects of Colistin Encapsulated in Chelating Complex Micelles for the Treatment of Multi-Drug-Resistant Gram-Negative Bacteria: A Pharmacokinetic Study
by Wei-Chuan Liao, Chau-Hui Wang, Tzu-Hui Sun, Yu-Cheng Su, Chia-Hung Chen, Wen-Teng Chang, Po-Lin Chen and Yow-Ling Shiue
Antibiotics 2023, 12(5), 836; https://doi.org/10.3390/antibiotics12050836 - 30 Apr 2023
Viewed by 1511
Abstract
Background: Infections caused by multi-drug-resistant Gram-negative bacteria (MDR-GNB) are an emerging problem globally. Colistin is the last-sort antibiotic for MDR-GNB, but its toxicity limits its clinical use. We aimed to test the efficacy of colistin-loaded micelles (CCM-CL) against drug-resistant Pseudomonas aeruginosa and compare [...] Read more.
Background: Infections caused by multi-drug-resistant Gram-negative bacteria (MDR-GNB) are an emerging problem globally. Colistin is the last-sort antibiotic for MDR-GNB, but its toxicity limits its clinical use. We aimed to test the efficacy of colistin-loaded micelles (CCM-CL) against drug-resistant Pseudomonas aeruginosa and compare their safety with that of free colistin in vitro and in vivo. Materials and methods: We incorporated colistin into chelating complex micelles (CCMs), thus producing colistin-loaded micelles (CCM-CL), and conducted both safety and efficacy surveys to elucidate their potential uses. Results: In a murine model, the safe dose of CCM-CL was 62.5%, which is much better than that achieved after the intravenous bolus injection of ‘free’ colistin. With a slow drug infusion, the safe dose of CCM-CL reached 16 mg/kg, which is double the free colistin, 8 mg/kg. The area under the curve (AUC) levels for CCM-CL were 4.09- and 4.95-fold higher than those for free colistin in terms of AUC0-t and AUC0-inf, respectively. The elimination half-lives of CCM-CL and free colistin groups were 12.46 and 102.23 min, respectively. In the neutropenic mice model with carbapenem-resistant Pseudomonas aeruginosa pneumonia, the 14-day survival rate of the mice treated with CCM-CL was 80%, which was significantly higher than the 30% in the free colistin group (p < 0.05). Conclusions: Our results showed that CCM-CL, an encapsulated form of colistin, is safe and effective, and thus may become a drug of choice against MDR-GNB. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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12 pages, 1745 KiB  
Article
Natamycin Has an Inhibitory Effect on Neofusicoccum parvum, the Pathogen of Chestnuts
by Lin-Jing Gou, Tian-Tian Liu, Qi Zeng, Wan-Rong Dong, Lu Wang, Sha Long, Jiang-Tao Su, Yu-Xin Chen and Gao Zhou
Molecules 2023, 28(9), 3707; https://doi.org/10.3390/molecules28093707 - 25 Apr 2023
Viewed by 1230
Abstract
This research aimed to investigate natamycin’s antifungal effect and its mechanism against the chestnut pathogen Neofusicoccum parvum. Natamycin’s inhibitory effects on N. parvum were investigated using a drug-containing plate culture method and an in vivo assay in chestnuts and shell buckets. The [...] Read more.
This research aimed to investigate natamycin’s antifungal effect and its mechanism against the chestnut pathogen Neofusicoccum parvum. Natamycin’s inhibitory effects on N. parvum were investigated using a drug-containing plate culture method and an in vivo assay in chestnuts and shell buckets. The antifungal mechanism of action of natamycin on N. parvum was investigated by conducting staining experiments of the fungal cell wall and cell membrane. Natamycin had a minimum inhibitory concentration (MIC) of 100 μg/mL and a minimum fungicidal concentration (MFC) of 200 μg/mL against N. parvum. At five times the MFC, natamycin had a strong antifungal effect on chestnuts in vivo, and it effectively reduced morbidity and extended the storage period. The cell membrane was the primary target of natamycin action against N. parvum. Natamycin inhibits ergosterol synthesis, disrupts cell membranes, and causes intracellular protein, nucleic acid, and other macromolecule leakages. Furthermore, natamycin can cause oxidative damage to the fungus, as evidenced by decreased superoxide dismutase and catalase enzyme activity. Natamycin exerts a strong antifungal effect on the pathogenic fungus N. parvum from chestnuts, mainly through the disruption of fungal cell membranes. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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15 pages, 7482 KiB  
Article
Preparation and Properties of (Sc2O3-MgO)/Pcl/Pvp Electrospun Nanofiber Membranes for the Inhibition of Escherichia coli Infections
by Yanjing Liu, Xiyue Li, Yuezhou Liu, Yaping Huang, Fuming Wang, Yongfang Qian and Ying Wang
Int. J. Mol. Sci. 2023, 24(8), 7649; https://doi.org/10.3390/ijms24087649 - 21 Apr 2023
Cited by 2 | Viewed by 1333
Abstract
Due to their high porosity, large specific surface area, and structural similarity with the extracellular matrix (ECM), electrospun nanofiber membranes are often endowed with the antibacterial properties for biomedical applications. The purpose of this study was to synthesize nano-structured Sc2O3-MgO by doping Sc [...] Read more.
Due to their high porosity, large specific surface area, and structural similarity with the extracellular matrix (ECM), electrospun nanofiber membranes are often endowed with the antibacterial properties for biomedical applications. The purpose of this study was to synthesize nano-structured Sc2O3-MgO by doping Sc3+, calcining at 600 °C, and then loading it onto the PCL/PVP substrates with electrospinning technology with the aim of developing new efficient antibacterial nanofiber membranes for tissue engineering. A scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDS) were used to study the morphology of all formulations and analyze the types and contents of the elements, and an X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform attenuated total reflection infrared spectroscopy (ATR-FTIR) were used for further analysis. The experimental results showed that the PCL/PVP (SMCV-2.0) nanofibers loaded with 2.0 wt% Sc2O3-MgO were smooth and homogeneous with an average diameter of 252.6 nm; the antibacterial test indicated that a low load concentration of 2.0 wt% Sc2O3-MgO in PCL/PVP (SMCV-2.0) showed a 100% antibacterial rate against Escherichia coli (E. coli). Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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20 pages, 4784 KiB  
Article
Synthesis and Antibiotic Activity of Chitosan-Based Comb-like Co-Polypeptides
by Timothy P. Enright, Dominic L. Garcia, Gia Storti, Jason E. Heindl and Alexander Sidorenko
Mar. Drugs 2023, 21(4), 243; https://doi.org/10.3390/md21040243 - 15 Apr 2023
Viewed by 1375
Abstract
Infections caused by multidrug-resistant Gram-negative bacteria have been named one of the most urgent global health threats due to antimicrobial resistance. Considerable efforts have been made to develop new antibiotic drugs and investigate the mechanism of resistance. Recently, Anti-Microbial Peptides (AMPs) have served [...] Read more.
Infections caused by multidrug-resistant Gram-negative bacteria have been named one of the most urgent global health threats due to antimicrobial resistance. Considerable efforts have been made to develop new antibiotic drugs and investigate the mechanism of resistance. Recently, Anti-Microbial Peptides (AMPs) have served as a paradigm in the design of novel drugs that are active against multidrug-resistant organisms. AMPs are rapid-acting, potent, possess an unusually broad spectrum of activity, and have shown efficacy as topical agents. Unlike traditional therapeutics that interfere with essential bacterial enzymes, AMPs interact with microbial membranes through electrostatic interactions and physically damage cell integrity. However, naturally occurring AMPs have limited selectivity and modest efficacy. Therefore, recent efforts have focused on the development of synthetic AMP analogs with optimal pharmacodynamics and an ideal selectivity profile. Hence, this work explores the development of novel antimicrobial agents which mimic the structure of graft copolymers and mirror the mode of action of AMPs. A family of polymers comprised of chitosan backbone and AMP side chains were synthesized via the ring-opening polymerization of the N-carboxyanhydride of l-lysine and l-leucine. The polymerization was initiated from the functional groups of chitosan. The derivatives with random- and block-copolymer side chains were explored as drug targets. These graft copolymer systems exhibited activity against clinically significant pathogens and disrupted biofilm formation. Our studies highlight the potential of chitosan-graft-polypeptide structures in biomedical applications. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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11 pages, 2581 KiB  
Article
Preparation and Evaluation of Zeolite Nanoparticles as a Delivery System for Helicoverpa armigera Nucleopolyhedrovirus (HaNPV) against the Spodoptera litura (Fabricius, 1775) Larvae
by Mia Miranti, Camellia Panatarani, I Made Joni, Maharani Herawan Ossa Putri, Hikmat Kasmara, Melanie Melanie, Desak Made Malini and Wawan Hermawan
Microorganisms 2023, 11(4), 847; https://doi.org/10.3390/microorganisms11040847 - 27 Mar 2023
Cited by 2 | Viewed by 1566
Abstract
Synthetic insecticides frequently cause pest resistance and destroy non-target organisms. Thus, virus formulation is an issue that deserves considerable attention in developing virus-based insecticides. The hindrance of using nucleopolyhedrovirus alone as a virus-based insecticide is due to slow lethal time, though its mortality [...] Read more.
Synthetic insecticides frequently cause pest resistance and destroy non-target organisms. Thus, virus formulation is an issue that deserves considerable attention in developing virus-based insecticides. The hindrance of using nucleopolyhedrovirus alone as a virus-based insecticide is due to slow lethal time, though its mortality remains high (100%). This paper reports the formulation of zeolite nanoparticles as a delivery system to accelerate lethal time in controlling Spodoptera litura (Fabr.). Zeolite nanoparticles were prepared using the beads-milling method. The statistical analysis was carried out by a description exploration method with six replications. The occlusion bodies’ concentration in the virus formulation was 4 × 107 OBs in 1 mL medium. Zeolite nanoparticles formulation sped up the lethal time significantly (7.67 days) compared to micro-size zeolite (12.70 days) and only nucleopolyhedrovirus (8.12 days) and received acceptable mortality (86.4%). The zeolite nanoparticles delivery system provides an alternative formulation for nucleopolyhedrovirus with a significantly improved speed of killing the virus while maintaining suitable efficacy of the virus preparation in terms of the prevalence of mortality. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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13 pages, 825 KiB  
Article
In Vitro Studies of Nanoparticles as a Potentially New Antimicrobial Agent for the Prevention and Treatment of Lameness and Digital Dermatitis in Cattle
by Magdalena Kot, Aleksandra Kalińska, Sławomir Jaworski, Mateusz Wierzbicki, Sebastian Smulski and Marcin Gołębiewski
Int. J. Mol. Sci. 2023, 24(7), 6146; https://doi.org/10.3390/ijms24076146 - 24 Mar 2023
Cited by 3 | Viewed by 1392
Abstract
Digital dermatitis (DD) is the second most prevalent disease in dairy cattle. It causes significant losses for dairy breeders and negatively impacts cows’ welfare and milk yield. Despite this, its etiology has not been entirely identified, and available data are limited. Antibiotic therapy [...] Read more.
Digital dermatitis (DD) is the second most prevalent disease in dairy cattle. It causes significant losses for dairy breeders and negatively impacts cows’ welfare and milk yield. Despite this, its etiology has not been entirely identified, and available data are limited. Antibiotic therapy is a practical method for managing animal health, but overuse has caused the evolution of antibiotic-resistant bacteria, leading to a loss in antimicrobial efficacy. The antimicrobial properties of metal nanoparticles (NPs) may be a potential alternative to antibiotics. The aim of this study was to determine the biocidal properties of AgNPs, CuNPs, AuNPs, PtNPs, FeNPs, and their nanocomposites against pathogens isolated from cows suffering from hoof diseases, especially DD. The isolated pathogens included Sphingomonas paucimobilis, Ochrobactrum intermedium I, Ochrobactrum intermedium II, Ochrobactrum gallinifaecis, and Actinomyces odontolyticus. Cultures were prepared in aerobic and anaerobic environments. The viability of the pathogens was then determined after applying nanoparticles at various concentrations. The in vitro experiment showed that AgNPs and CuNPs, and their complexes, had the highest biocidal effect on pathogens. The NPs’ biocidal properties and their synergistic effects were confirmed, which may forecast their use in the future treatment and the prevention of lameness in cows, especially DD. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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12 pages, 851 KiB  
Article
Methacrylate Cationic Nanoparticles Activity against Different Gram-Positive Bacteria
by Syong H. Nam-Cha, Ana V. Ocaña, Ramón Pérez-Tanoira, John J. Aguilera-Correa, Abraham J. Domb, Marta C. Ruiz-Grao, Sandra Cebada-Sánchez, Ángel López-Gónzalez, Milagros Molina-Alarcón, Juan Pérez-Martínez and Francisco C. Pérez-Martínez
Antibiotics 2023, 12(3), 533; https://doi.org/10.3390/antibiotics12030533 - 07 Mar 2023
Viewed by 1629
Abstract
Nanotechnology is a developing field that has boomed in recent years due to the multiple qualities of nanoparticles (NPs), one of which is their antimicrobial capacity. We propose that NPs anchored with 2-(dimethylamino)ethyl methacrylate (DMAEMA) have antibacterial properties and could constitute an alternative [...] Read more.
Nanotechnology is a developing field that has boomed in recent years due to the multiple qualities of nanoparticles (NPs), one of which is their antimicrobial capacity. We propose that NPs anchored with 2-(dimethylamino)ethyl methacrylate (DMAEMA) have antibacterial properties and could constitute an alternative tool in this field. To this end, the antimicrobial effects of three quaternised NPs anchored with DMAEMA were studied. These NPs were later copolymerized using different methylmethacrylate (MMA) concentrations to evaluate their role in the antibacterial activity shown by NPs. Clinical strains of Staphylococcus aureus, S. epidermidis, S. lugdunensis and Enterococcus faecalis were used to assess antibacterial activity. The minimal inhibitory concentration (MIC) was determined at the different concentrations of NPs to appraise antibacterial activity. The cytotoxic effects of the NPs anchored with DMAEMA were determined in NIH3T3 mouse fibroblast cultures by MTT assays. All the employed NPs were effective against the studied bacterial strains, although increasing concentrations of the MMA added during the synthesis process diminished these effects without altering toxicity in cell cultures. To conclude, more studies with other copolymers are necessary to improve the antibacterial effects of NPs anchored with DMAEMA. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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19 pages, 2674 KiB  
Article
Development of a Novel Antibacterial Peptide, PAM-5, via Combination of Phage Display Selection and Computer-Assisted Modification
by Hawk Leong Yuen, Szn Yi Chan, Yi En Ding, Suxing Lim, Gim Cheong Tan and Chiew Ling Kho
Biomolecules 2023, 13(3), 466; https://doi.org/10.3390/biom13030466 - 02 Mar 2023
Cited by 4 | Viewed by 1924
Abstract
Antibacterial peptides (ABPs) have been proposed as potential candidates for alternative antibacterial agents due to the extensive dissemination of antibiotic resistance. However, ABP isolation from natural resources can be tedious without consistent yield. Moreover, many natural ABPs are not developed for clinical application [...] Read more.
Antibacterial peptides (ABPs) have been proposed as potential candidates for alternative antibacterial agents due to the extensive dissemination of antibiotic resistance. However, ABP isolation from natural resources can be tedious without consistent yield. Moreover, many natural ABPs are not developed for clinical application due to potential toxicity to mammalian cells. Therefore, the objective of this study was to develop a potent ABP with minimal toxicity via phage display selection followed by computer-assisted modification. Briefly, a 12-mer phage-displayed peptide library was used to isolate peptides that bound to the cell surface of Pseudomonas aeruginosa with high affinity. The affinity-selected peptide with the highest selection frequency was modified to PAM-5 (KWKWRPLKRKLVLRM) with enhanced antibacterial features by using an online peptide database. Using in vitro microbroth dilution assay, PAM-5 was shown to be active against a panel of Gram-negative bacteria and selected Gram-positive bacteria. Interestingly, the peptide was stable in human plasma by exhibiting a similar bactericidal effect via ex vivo assay. Scanning electron microscopy and SYTOX Green uptake assay revealed that PAM-5 was able to cause membrane disruption and permeabilization of the bacteria. Additionally, the peptide was also able to bind to bacterial DNA as demonstrated by gel retardation assay. In the time-kill assay, PAM-5 was shown to kill the bacteria rapidly in 10 min. More importantly, PAM-5 was non-cytotoxic to Vero cells and non-haemolytic to human erythrocytes at all concentrations tested for the antibacterial assays. Thus, this study showed that the combination of phage display screening and computer-assisted modification could be used to develop potent novel ABPs, and PAM-5 derived from these approaches is worth to be further elucidated for its potential clinical use. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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20 pages, 1311 KiB  
Review
Hybrid Nanosystems of Antibiotics with Metal Nanoparticles—Novel Antibacterial Agents
by Tatyana I. Shabatina, Olga I. Vernaya and Mikhail Y. Melnikov
Molecules 2023, 28(4), 1603; https://doi.org/10.3390/molecules28041603 - 07 Feb 2023
Cited by 7 | Viewed by 2122
Abstract
The appearance and increasing number of microorganisms resistant to the action of antibiotics is one of the global problems of the 21st century. Already, the duration of therapeutic treatment and mortality from infectious diseases caused by pathogenic microorganisms have increased significantly over the [...] Read more.
The appearance and increasing number of microorganisms resistant to the action of antibiotics is one of the global problems of the 21st century. Already, the duration of therapeutic treatment and mortality from infectious diseases caused by pathogenic microorganisms have increased significantly over the last few decades. Nanoscale inorganic materials (metals and metal oxides) with antimicrobial potential are a promising solution to this problem. Here we discuss possible mechanisms of pathogenic microorganisms’ resistance to antibiotics, proposed mechanisms of action of inorganic nanoparticles on bacterial cells, and the possibilities and benefits of their combined use with antibacterial drugs. The prospects of using metal and metal oxide nanoparticles as carriers in targeted delivery systems for antibacterial compositions are also discussed. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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17 pages, 7129 KiB  
Article
Synthesis, In Silico Study, Antibacterial and Antifungal Activities of N-phenylbenzamides
by Melanny Ika Sulistyowaty, Galih Satrio Putra, Tutuk Budiati, Anastasia Wheni Indrianingsih, Farida Anwari, Dini Kesuma, Katsuyoshi Matsunami and Takayasu Yamauchi
Int. J. Mol. Sci. 2023, 24(3), 2745; https://doi.org/10.3390/ijms24032745 - 01 Feb 2023
Cited by 2 | Viewed by 1895
Abstract
Antibiotic and antifungal resistance problems have been prevalent in recent decades. One of the efforts to solve the problems is to develop new medicines with more potent antibacterial and antifungal activity. N-phenylbenzamides have the potential to be developed as antibacterial and antifungal [...] Read more.
Antibiotic and antifungal resistance problems have been prevalent in recent decades. One of the efforts to solve the problems is to develop new medicines with more potent antibacterial and antifungal activity. N-phenylbenzamides have the potential to be developed as antibacterial and antifungal medicine. This study aimed to synthesize N-phenylbenzamides and evaluate their in silico and in vitro antibacterial and antifungal activities. The in silico studies conducted absorption, distribution, metabolism, excretion and toxicity (ADMET) predictions along with molecular docking studies. ADMET predictions used pkCSM software online, while the docking studies used MVD software (Molegro ® Virtual Docker version 5.5) on Aminoglycosid-2 ″-phosphotransferase-IIa (APH2 ″-IIa) enzyme with protein data bank (PDB) ID code 3HAV as antibacterial and aspartic proteinases enzyme (Saps) with PDB ID code 2QZX as an antifungal. In vitro, antibacterial and antifungal tests were carried out using the zone of inhibition (ZOI) method. The five N-phenylbenzamides (3ae) were successfully synthesized with a high yield. Based on in silico and in vitro studies, compounds 3ae have antibacterial and antifungal activities, where they can inhibit the growth of Gram-positive bacteria (Staphylococcus aureus), Gram-negative (Escherichia coli), and Candida albicans. Therefore, compounds 3ae can be developed as a topical antibacterial and antifungal agent. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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14 pages, 5793 KiB  
Article
Synthesis of Antimicrobial Chitosan-Silver Nanoparticles Mediated by Reusable Chitosan Fungal Beads
by Edward Hermosilla, Marcela Díaz, Joelis Vera, María José Contreras, Karla Leal, Rodrigo Salazar, Leticia Barrientos, Gonzalo Tortella and Olga Rubilar
Int. J. Mol. Sci. 2023, 24(3), 2318; https://doi.org/10.3390/ijms24032318 - 24 Jan 2023
Cited by 3 | Viewed by 1964
Abstract
Nanoparticles, especially silver nanoparticles (Ag NPs), have gained significant attention in recent years as potential alternatives to traditional antibiotics for treating infectious diseases due to their ability to inhibit the growth of microorganisms effectively. Ag NPs can be synthesized using fungi extract, but [...] Read more.
Nanoparticles, especially silver nanoparticles (Ag NPs), have gained significant attention in recent years as potential alternatives to traditional antibiotics for treating infectious diseases due to their ability to inhibit the growth of microorganisms effectively. Ag NPs can be synthesized using fungi extract, but the method is not practical for large-scale production due to time and biomass limitations. In this study, we explore the use of chitosan to encapsulate the mycelia of the white-rot fungus Stereum hirsutum and form chitosan fungal beads for use in multiple extractions and nanoparticle synthesis. The resulting nanoparticles were characterized using various techniques, including UV-vis spectrophotometry, transmission electron microscopy, dynamic light scattering, and X-ray diffraction analysis. The analysis revealed that the synthesized nanoparticles were composed of chitosan-silver nanoparticles (CS-Ag NPs) with a size of 25 nm. The chitosan fungal beads were reused in three extractions and nanoparticle synthesis before they lost their ability to produce CS-Ag NPs. The CS-Ag NPs showed potent antimicrobial activity against phytopathogenic and human pathogenic microorganisms, including Pseudomonas syringae, Escherichia coli, Staphylococcus aureus, and Candida albicans, with minimum inhibitory concentrations of 1.5, 1.6, 3.1, and 4 µg/mL, respectively. The antimicrobial activity of CS-Ag NPs was from 2- to 40-fold higher than Ag NPs synthesized using an aqueous extract of unencapsulated fungal biomass. The CS-Ag NPs were most effective at a pH of five regarding the antimicrobial activity. These results suggest that the chitosan fungal beads may be a promising alternative for the sustainable and cost-effective synthesis of CS-Ag NPs with improved antimicrobial activity. Full article
(This article belongs to the Topic Antimicrobial Agents and Nanomaterials)
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