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1.
PLoS One ; 16(9): e0251951, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34473709

RESUMO

The purpose of this study was to explore potential mechanisms of cytotoxicity towards HeLa and HT29 cells displayed by Pediocin PA-1. We did this by carrying out sequence alignments and 3D modelling of related bacteriocins which have been studied in greater detail: Microcin E492, Enterocin AB heterodimer and Divercin V41. Microcin E492 interacts with Toll-Like Receptor 4 in order to activate an apoptosis reaction, sequence alignment showed a high homology between Pediocin PA-1 and Microcin E492 whereas 3D modelling showed Pediocin PA-1 interacting with TLR-4 in a way reminiscent of Microcin E492. Furthermore, Pediocin PA-1 had the highest homology with the Enterocin heterodimer, particularly chain A; Enterocin has also shown to cause an apoptotic response in cancer cells. Based on this we are led to strongly believe Pediocin PA-1 interacts with TLRs in order to cause cell death. If this is the case, it would explain the difference in cytotoxicity towards HeLa over HT29 cells, due to difference in expression of particular TLRs. Overall, we believe Pediocin PA-1 exhibits a dual effect which is dose dependant, like that of Microcin. Unfortunately, due to the COVID-19 pandemic, we were unable to carry out experiments in the lab, and the unavailability of important data meant we were unable to provide and validate out solid conclusions, but rather suggestions. However, bioinformatic analysis is still able to provide information regarding structure and sequence analysis to draw plausible and evidence based conclusions. We have been able to highlight interesting findings and how these could be translated into future research and therapeutics in order to improve the quality of treatment and life of cancer patients.


Assuntos
Bacteriocinas/química , Bacteriocinas/farmacologia , Pediocinas/química , Pediocinas/farmacologia , Conformação Proteica , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Bacteriocinas/genética , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/farmacologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Sobrevivência Celular/efeitos dos fármacos , Células HT29 , Células HeLa , Humanos , Modelos Moleculares , Pandemias , Pediocinas/genética , SARS-CoV-2/fisiologia , Homologia de Sequência de Aminoácidos , Receptor 4 Toll-Like/metabolismo
2.
Molecules ; 26(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361848

RESUMO

The industrial processing of crude propolis generates residues. Essential oils (EOs) from propolis residues could be a potential source of natural bioactive compounds to replace antibiotics and synthetic antioxidants in pig production. In this study, we determined the antibacterial/antioxidant activity of EOs from crude organic propolis (EOP) and from propolis residues, moist residue (EOMR), and dried residue (EODR), and further elucidated their chemical composition. The EOs were extracted by hydrodistillation, and their volatile profile was tentatively identified by GC-MS. All EOs had an antibacterial effect on Escherichia coli and Lactobacillus plantarum as they caused disturbances on the growth kinetics of both bacteria. However, EODR had more selective antibacterial activity, as it caused a higher reduction in the maximal culture density (D) of E. coli (86.7%) than L. plantarum (46.9%). EODR exhibited mild antioxidant activity, whereas EOMR showed the highest antioxidant activity (ABTS = 0.90 µmol TE/mg, FRAP = 463.97 µmol Fe2+/mg) and phenolic content (58.41 mg GAE/g). Each EO had a different chemical composition, but α-pinene and ß-pinene were the major compounds detected in the samples. Interestingly, specific minor compounds were detected in a higher relative amount in EOMR and EODR as compared to EOP. Therefore, these minor compounds are most likely responsible for the biological properties of EODR and EOMR. Collectively, our findings suggest that the EOs from propolis residues could be resourcefully used as natural antibacterial/antioxidant additives in pig production.


Assuntos
Antibacterianos , Antioxidantes , Escherichia coli/crescimento & desenvolvimento , Lactobacillus plantarum/crescimento & desenvolvimento , Óleos Voláteis , Própole/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia
3.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445625

RESUMO

Arthropod antimicrobial peptides (AMPs) offer a promising source of new leads to address the declining number of novel antibiotics and the increasing prevalence of multidrug-resistant bacterial pathogens. AMPs with potent activity against Gram-negative bacteria and distinct modes of action have been identified in insects and scorpions, allowing the discovery of AMP combinations with additive and/or synergistic effects. Here, we tested the synergistic activity of two AMPs, from the dung beetle Copris tripartitus (CopA3) and the scorpion Heterometrus petersii (Hp1090), against two strains of Escherichia coli. We also tested the antibacterial activity of two hybrid peptides generated by joining CopA3 and Hp1090 with linkers comprising two (InSco2) or six (InSco6) glycine residues. We found that CopA3 and Hp1090 acted synergistically against both bacterial strains, and the hybrid peptide InSco2 showed more potent bactericidal activity than the parental AMPs or InSco6. Molecular dynamics simulations revealed that the short linker stabilizes an N-terminal 310-helix in the hybrid peptide InSco2. This secondary structure forms from a coil region that interacts with phosphatidylethanolamine in the membrane bilayer model. The highest concentration of the hybrid peptides used in this study was associated with stronger hemolytic activity than equivalent concentrations of the parental AMPs. As observed for CopA3, the increasing concentration of InSco2 was also cytotoxic to BHK-21 cells. We conclude that AMP hybrids linked by glycine spacers display potent antibacterial activity and that the cytotoxic activity can be modulated by adjusting the nature of the linker peptide, thus offering a strategy to produce hybrid peptides as safe replacements or adjuncts for conventional antibiotic therapy.


Assuntos
Antibacterianos/farmacologia , Artrópodes/química , Bactérias/efeitos dos fármacos , Glicina/química , Hemólise/efeitos dos fármacos , Rim/efeitos dos fármacos , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Animais , Antibacterianos/química , Apoptose , Células Cultivadas , Cricetinae , Camundongos , Proteínas Citotóxicas Formadoras de Poros/química
4.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445410

RESUMO

Development of novel therapeutics to treat antibiotic-resistant infections, especially those caused by ESKAPE pathogens, is urgent. One of the most critical pathogens is P. aeruginosa, which is able to develop a large number of factors associated with antibiotic resistance, including high level of impermeability. Gram-negative bacteria are protected from the environment by an asymmetric Outer Membrane primarily composed of lipopolysaccharides (LPS) at the outer leaflet and phospholipids in the inner leaflet. Based on a large hemi-synthesis program focusing on amphiphilic aminoglycoside derivatives, we extend the antimicrobial activity of 3',6-dinonyl neamine and its branched isomer, 3',6-di(dimethyloctyl) neamine on clinical P. aeruginosa, ESBL, and carbapenemase strains. We also investigated the capacity of 3',6-homodialkyl neamine derivatives carrying different alkyl chains (C7-C11) to interact with LPS and alter membrane permeability. 3',6-Dinonyl neamine and its branched isomer, 3',6-di(dimethyloctyl) neamine showed low MICs on clinical P. aeruginosa, ESBL, and carbapenemase strains with no MIC increase for long-duration incubation. In contrast from what was observed for membrane permeability, length of alkyl chains was critical for the capacity of 3',6-homodialkyl neamine derivatives to bind to LPS. We demonstrated the high antibacterial potential of the amphiphilic neamine derivatives in the fight against ESKAPE pathogens and pointed out some particular characteristics making the 3',6-dinonyl- and 3',6-di(dimethyloctyl)-neamine derivatives the best candidates for further development.


Assuntos
Compostos Alílicos/farmacologia , Antibacterianos/farmacologia , Framicetina/química , Bactérias Gram-Negativas/crescimento & desenvolvimento , Lipopolissacarídeos/metabolismo , Compostos Alílicos/síntese química , Compostos Alílicos/química , Antibacterianos/síntese química , Antibacterianos/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/metabolismo , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo
5.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443612

RESUMO

Eucalyptus leaves (ELE) and willow bark (WBE) extracts were utilized towards the formation of silver nanoparticles (AgNPs(ELE), AgNPs(WBE)). AgNPs(ELE) and AgNPs(WBE) were dispersed in polymer hydrogels to create pHEMA@AgNPs(ELE)_2 and pHEMA@AgNPs(WBE)_2 using hydroxyethyl-methacrylate (HEMA). The materials were characterized in a solid state by X-ray fluorescence (XRF) spectroscopy, X-ray powder diffraction analysis (XRPD), thermogravimetric differential thermal analysis (TG-DTA), differential scanning calorimetry (DTG/DSC) and attenuated total reflection spectroscopy (ATR-FTIR) and ultraviolet visible (UV-vis) spectroscopy in solution. The antimicrobial potential of the materials was investigated against the Gram-negative bacterial strain Pseudomonas aeruginosa (P. aeruginosa) and the Gram-positive bacterial strain of the genus Staphylococcus epidermidis (S. epidermidis) and Staphylococcus aureus (S. aureus), which are involved in microbial keratitis. The percentage of bacterial viability of P. aeruginosa and S. epidermidis upon their incubation over the pHEMA@AgNPs(ELE)_2 discs is interestingly low (28.3 and 6.8% respectively), while the inhibition zones (IZ) formed are 12.3 ± 1.7 and 13.2 ± 1.2 mm, respectively. No in vitro toxicity of this material towards human corneal epithelial cells (HCEC) was detected. Despite its low performance against S. aureus, pHEMA@AgNPs(ELE)_2 could be an efficient candidate towards the development of contact lenses that reduces microbial infection risk.


Assuntos
Lentes de Contato/microbiologia , Eucalyptus/química , Hidrogéis/química , Extratos Vegetais/química , Salix/química , Prata/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Humanos , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata/química
6.
ACS Appl Mater Interfaces ; 13(33): 38947-38958, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433245

RESUMO

Although dressing blood-contacting devices with robust and synergistic antibacterial and antithrombus properties has been explored for several decades, it still remains a great challenge. In order to endow materials with remarkable antibacterial and antithrombus abilities, a stable and antifouling hydrogel coating was developed via surface-initiated polymerization of sulfobetaine methacrylate and acrylic acid on a polymeric substrate followed by embedding of antimicrobial peptides (AMPs), including WR (sequence: WRWRWR-NH2) or Bac2A (sequence: RLARIVVIRVAR-NH2) AMPs. The chemical composition of the AMP-embedded hydrogel coating was determined through XPS, zeta potential, and SEM-EDS measurements. The AMP-embedded antifouling hydrogel coating showed not only good hemocompatibility but also excellent bactericidal and antiadhesion properties against Gram-positive and Gram-negative bacteria. Moreover, the hydrogel coating could protect the AMPs with long-term bioactivity and cover the positive charge of the dotted distributed AMPs, which in turn well retained the hemocompatibility and antifouling capacity of the bulk hydrogels. Furthermore, the microbiological results of animal experiments also verified the anti-infection performance in vivo. Histological and immunological data further indicated that the hydrogel coating had an excellent anti-inflammatory function. Therefore, the present study might provide a promising approach to prevent bacterial infections and thrombosis in clinical applications of blood-contacting devices and related implants.


Assuntos
Antibacterianos/química , Materiais Revestidos Biocompatíveis/química , Fibrinolíticos/química , Hidrogéis/química , Proteínas Citotóxicas Formadoras de Poros/química , Resinas Acrílicas/química , Antibacterianos/farmacologia , Bandagens , Sangue/metabolismo , Sobrevivência Celular , Materiais Revestidos Biocompatíveis/metabolismo , Eritrócitos , Fibrinolíticos/farmacologia , Hemólise , Humanos , Hidrogéis/metabolismo , Metacrilatos/química , Adesividade Plaquetária/efeitos dos fármacos , Polimerização , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Propriedades de Superfície
7.
ACS Appl Mater Interfaces ; 13(33): 38979-38989, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34433249

RESUMO

Chronic infections caused by Pseudomonas aeruginosa pose severe threats to human health. Traditional antibiotic therapy has lost its total supremacy in this battle. Here, nanoplatforms activated by the clinical microenvironment are developed to treat P. aeruginosa infection on the basis of dynamic borate ester bonds. In this design, the nanoplatforms expose targeted groups for bacterial capture after activation by an acidic infection microenvironment, resulting in directional transport delivery of the payload to bacteria. Subsequently, the production of hyperpyrexia and reactive oxygen species enhances antibacterial efficacy without systemic toxicity. Such a formulation with a diameter less than 200 nm can eliminate biofilm up to 75%, downregulate the level of cytokines, and finally promote lung repair. Collectively, the biomimetic design with phototherapy killing capability has the potential to be an alternative strategy against chronic infections caused by P. aeruginosa.


Assuntos
Antibacterianos/química , Verde de Indocianina/química , Nanocápsulas/química , Fármacos Fotossensibilizantes/química , Polímeros/química , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/radioterapia , Células A549 , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Composição de Medicamentos , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Humanos , Verde de Indocianina/farmacologia , Raios Infravermelhos , Masculino , Metacrilatos/química , Camundongos Endogâmicos BALB C , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Polietilenoglicóis/química , Pseudomonas aeruginosa/efeitos dos fármacos
8.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445408

RESUMO

The mechanism of sulfisoxazole (SFF) selective removal by photocatalysis in the presence of titanium (IV) oxide (TiO2) and iron (III) chloride (FeCl3) was explained and the kinetics and degradation pathways of SFF and other antibiotics were compared. The effects of selected inorganic ions, oxygen conditions, pH, sorption processes and formation of coordination compounds on the photocatalytic process in the presence of TiO2 were also determined. The Fe3+ compounds added to the irradiated sulfonamide (SN) solution underwent surface sorption on TiO2 particles and act as acceptors of excited electrons. Most likely, the SFF degradation is also intensified by organic radicals or cation organic radicals. These radicals can be initially generated by reaction with electron holes, hydroxyl radicals and as a result of electron transfer mediated by iron ions and then participate in propagation processes. The high sensitivity of SFF to decomposition caused by organic radicals is associated with the steric effect and the high bond polarity of the amide substituent.


Assuntos
Antibacterianos/química , Sulfonamidas/química , Titânio/química , Catálise , Concentração de Íons de Hidrogênio , Cinética , Compostos Orgânicos , Fotólise , Sulfisoxazol/química , Purificação da Água
9.
Molecules ; 26(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34361632

RESUMO

The present study focuses on the biological synthesis, characterization, and antibacterial activities of silver nanoparticles (AgNPs) using extracellular extracts of Aspergillus japonicus PJ01.The optimal conditions of the synthesis process were: 10 mL of extracellular extracts, 1 mL of AgNO3 (0.8 mol/L), 4 mL of NaOH solution (1.5 mol/L), 30 °C, and a reaction time of 1 min. The characterizations of AgNPs were tested by UV-visible spectrophotometry, zeta potential, scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric (TG) analyses. Fourier transform infrared spectroscopy (FTIR) analysis showed that Ag+ was reduced by the extracellular extracts, which consisted chiefly of soluble proteins and reducing sugars. In this work, AgNO3 concentration played an important role in the physicochemical properties and antibacterial properties of AgNPs. Under the AgNO3 concentration of 0.2 and 0.8 mol/L, the diameters of AgNPs were 3.8 ± 1.1 and 9.1 ± 2.9 nm, respectively. In addition, smaller-sized AgNPs showed higher antimicrobial properties, and the minimum inhibitory concentration (MIC) values against both E. coli and S. aureus were 0.32 mg/mL.


Assuntos
Antibacterianos , Aspergillus/metabolismo , Química Verde/métodos , Nanopartículas Metálicas/química , Prata/química , Antibacterianos/química , Antibacterianos/farmacologia
10.
Molecules ; 26(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34361651

RESUMO

Here we introduce a new method aiming the immobilization of bioactive principles onto polymeric substrates, combining a surface activation and emulsion entrapment approach. Natural products with antimicrobial/antioxidant properties (essential oil from Syzygium aromaticum-clove and vegetal oil from Argania spinosa L-argan) were stabilized in emulsions with chitosan, a natural biodegradable polymer that has antimicrobial activity. The emulsions were laid on poly(lactic acid) (PLA), a synthetic biodegradable plastic from renewable resources, which was previously activated by plasma treatment. Bioactive materials were obtained, with low permeability for oxygen, high radical scavenging activity and strong inhibition of growth for Listeria monocytogenes, Salmonella Typhimurium and Escherichia coli bacteria. Clove oil was better dispersed in a more stable emulsion (no separation after six months) compared with argan oil. This leads to a compact and finely structured coating, with better overall properties. While both clove and argan oils are highly hydrophobic, the coatings showed increased hydrophilicity, especially for argan, due to preferential interactions with different functional groups in chitosan. The PLA films coated with oil-loaded chitosan showed promising results in retarding the food spoilage of meat, and especially cheese. Argan, and in particular, clove oil offered good UV protection, suitable for sterilization purposes. Therefore, using the emulsion stabilization of bioactive principles and immobilization onto plasma activated polymeric surfaces we obtained a bioactive material that combines the physical properties and the biodegradability of PLA with the antibacterial activity of chitosan and the antioxidant function of vegetal oils. This prevents microbial growth and food oxidation and could open new perspectives in the field of food packaging materials.


Assuntos
Quitosana , Óleo de Cravo , Emulsões , Microbiologia de Alimentos/métodos , Embalagem de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Óleos Vegetais , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Quitosana/farmacologia , Óleo de Cravo/química , Óleo de Cravo/farmacologia , Emulsões/química , Emulsões/farmacologia , Óleos Vegetais/química , Óleos Vegetais/farmacologia
11.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361712

RESUMO

The genus Maytenus is a member of the Celastraceae family, of which several species have long been used in traditional medicine. Between 1976 and 2021, nearly 270 new compounds have been isolated and elucidated from the genus Maytenus. Among these, maytansine and its homologues are extremely rare in nature. Owing to its unique skeleton and remarkable bioactivities, maytansine has attracted many synthetic endeavors in order to construct its core structure. In this paper, the current status of the past 45 years of research on Maytenus, with respect to its chemical and biological activities are discussed. The chemical research includes its structural classification into triterpenoids, sesquiterpenes and alkaloids, along with several chemical synthesis methods of maytansine or maytansine fragments. The biological activity research includes activities, such as anti-tumor, anti-bacterial and anti-inflammatory activities, as well as HIV inhibition, which can provide a theoretical basis for the better development and utilization of the Maytenus.


Assuntos
Alcaloides/química , Maitansina/análogos & derivados , Maytenus/química , Compostos Fitoquímicos/química , Sesquiterpenos/química , Triterpenos/química , Alcaloides/classificação , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Fármacos Anti-HIV/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Humanos , Maitansina/isolamento & purificação , Maitansina/farmacologia , Maytenus/metabolismo , Estrutura Molecular , Compostos Fitoquímicos/classificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais , Sesquiterpenos/classificação , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade , Triterpenos/classificação , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
12.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361723

RESUMO

Genito-urinary tract infections have a high incidence in the general population, being more prevalent among women than men. These diseases are usually treated with antibiotics, but very frequently, they are recurrent and lead to the creation of resistance and are associated with increased morbidity and mortality. For this reason, it is necessary to develop new compounds for their treatment. In this work, our objective is to review the characteristics of the compounds of a new formulation called Itxasol© that is prescribed as an adjuvant for the treatment of UTIs and composed of ß-arbutin, umbelliferon and n-acetyl cysteine. This formulation, based on biomimetic principles, makes Itxasol© a broad-spectrum antibiotic with bactericidal, bacteriostatic and antifungal properties that is capable of destroying the biofilm and stopping its formation. It also acts as an anti-inflammatory agent, without the adverse effects associated with the recurrent use of antibiotics that leads to renal nephrotoxicity and other side effects. All these characteristics make Itxasol© an ideal candidate for the treatment of UTIs since it behaves like an antibiotic and with better characteristics than other adjuvants, such as D-mannose and cranberry extracts.


Assuntos
Acetilcisteína/uso terapêutico , Arbutina/uso terapêutico , Produtos Biológicos/uso terapêutico , Umbeliferonas/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Acetilcisteína/química , Antibacterianos/química , Antibacterianos/uso terapêutico , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Antifúngicos/química , Antifúngicos/uso terapêutico , Arbutina/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Produtos Biológicos/química , Materiais Biomiméticos/química , Materiais Biomiméticos/uso terapêutico , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Combinação de Medicamentos , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/patogenicidade , Humanos , Masculino , Testes de Sensibilidade Microbiana , Umbeliferonas/química , Infecções Urinárias/microbiologia , Infecções Urinárias/patologia
13.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361725

RESUMO

This study investigated supercritical solvent impregnation of polyamide microfiltration membranes with carvacrol and the potential application of the modified membranes in ventilation of open surgical wounds. The impregnation process was conducted in batch mode at a temperature of 40 °C under pressures of 10, 15, and 20 MPa for contact times from 1 to 6 h. FTIR was applied to confirm the presence of carvacrol on the membrane surface. In the next step, the impact of the modification on the membrane structure was studied using scanning electron and ion beam microscopy and cross-filtration tests. Further, the release of carvacrol in carbon dioxide was determined, and finally, an open thoracic cavity model was applied to evaluate the efficiency of carvacrol-loaded membranes in contamination prevention. Carvacrol loadings of up to 43 wt.% were obtained under the selected operating conditions. The swelling effect was detectable. However, its impact on membrane functionality was minor. An average of 18.3 µg of carvacrol was released from membranes per liter of carbon dioxide for the flow of interest. Membranes with 30-34 wt.% carvacrol were efficient in the open thoracic cavity model applied, reducing the contamination levels by 27% compared to insufflation with standard membranes.


Assuntos
Antibacterianos/farmacologia , Cimenos/farmacologia , Nylons/química , Agentes Molhantes/farmacologia , Antibacterianos/química , Bandagens/microbiologia , Dióxido de Carbono/química , Cimenos/química , Liberação Controlada de Fármacos , Humanos , Insuflação , Cinética , Manequins , Membranas Artificiais , Ferida Cirúrgica/reabilitação , Molhabilidade , Agentes Molhantes/química
14.
Inorg Chem ; 60(17): 12730-12734, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34382773

RESUMO

Can a minor difference in the nonmetal binding sequence of antimicrobial clavanins explain the drastic change in the coordination environment and antimicrobial efficiency? This study answers the question with a definite "yes", showing the details of the bioinorganic chemistry of Zn(II) and Cu(II) complexes with clavanins, histidine-rich, antimicrobial peptides from hemocytes of the tunicate Styela clava.


Assuntos
Antibacterianos/farmacologia , Proteínas Sanguíneas/farmacologia , Complexos de Coordenação/farmacologia , Sequência de Aminoácidos , Antibacterianos/química , Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Proteínas Sanguíneas/química , Proteínas Sanguíneas/toxicidade , Candida albicans/efeitos dos fármacos , Linhagem Celular , Complexos de Coordenação/química , Complexos de Coordenação/toxicidade , Cobre/química , Humanos , Testes de Sensibilidade Microbiana , Zinco/química
15.
Molecules ; 26(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34443318

RESUMO

In this study, the surface-initiated atom transfer radical polymerization (SI-ATRP) technique and electroless deposition of silver (Ag) were used to prepare a novel multi-functional cotton (Cotton-Ag), possessing both conductive and antibacterial behaviors. It was found that the optimal electroless deposition time was 20 min for a weight gain of 40.4%. The physical and chemical properties of Cotton-Ag were investigated. It was found that Cotton-Ag was conductive and showed much lower electrical resistance, compared to the pristine cotton. The antibacterial properties of Cotton-Ag were also explored, and high antibacterial activity against both Escherichia coli and Staphylococcus aureus was observed.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Fibra de Algodão/análise , Condutividade Elétrica , Prata/química , Prata/farmacologia
16.
Molecules ; 26(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34443334

RESUMO

Background. The past decades have seen numerous efforts to develop new antitubercular agents. Currently, the available regimens are lengthy, only partially effective, and associated with high rates of adverse events. The challenge is therefore to develop new agents with faster and more efficient action. The versatile quinoxaline ring possesses a broad spectrum of pharmacological activities, ensuring considerable attention to it in the field of medicinal chemistry. Objectives. In continuation of our program on the pharmacological activity of quinoxaline derivatives, this review focuses on potential antimycobacterial activity of recent quinoxaline derivatives and discusses their structure-activity relationship for designing new analogs with improved activity. Methods. The review compiles recent studies published between January 2011 and April 2021. Results. The final total of 23 studies were examined. Conclusions. Data from studies of quinoxaline and quinoxaline 1,4-di-N-oxide derivatives highlight that specific derivatives show encouraging perspectives in the treatment of Mycobacterium tuberculosis and the recent growing interest for these scaffolds. These interesting results warrant further investigation, which may allow identification of novel antitubercular candidates based on this scaffold.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Quinoxalinas/química , Quinoxalinas/farmacologia , Relação Estrutura-Atividade
17.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443354

RESUMO

If plasma polymer thin films are to be synthesised from sustainable and natural precursors of chemically heterogeneous composition, it is important to understand the extent to which this composition influences the mechanism of polymerisation. To this end, a well-studied monoterpene alcohol, terpinen-4-ol, has been targeted for a comparative study with the naturally occurring mix of terpenes (viz. Melaleuca alternifolia oil) from which it is commonly distilled. Positive ion mode mass spectra of both terpinen-4-ol and M. alternifolia oil showed a decrease in disparities between the type and abundance of cationic species formed in their respective plasma environments as applied plasma power was increased. Supplementary biological assay revealed the antibacterial action of both terpinen-4-ol and M. alternifolia derived coatings with respect to S. aureus bacteria, whilst cytocompatibility was demonstrated by comparable eukaryotic cell adhesion to both coatings. Elucidating the processes occurring within the reactive plasmas can enhance the economics of plasma polymer deposition by permitting use of the minimum power, time and precursor pre-processing required to control the extent of monomer fragmentation and fabricate a film of the desired thickness and functionality.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Produtos Biológicos/química , Gases em Plasma/química , Staphylococcus aureus/efeitos dos fármacos , Terpenos/química , Terpenos/farmacologia , Melaleuca/química
18.
Molecules ; 26(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34443363

RESUMO

The antimicrobial properties of herbs from Papaveraceae have been used in medicine for centuries. Nevertheless, mutual relationships between the individual bioactive substances contained in these plants remain poorly elucidated. In this work, phytochemical composition of extracts from the aerial and underground parts of five Papaveraceae species (Chelidonium majus L., Corydalis cava (L.) Schweigg. and Körte, C. cheilanthifolia Hemsl., C. pumila (Host) Rchb., and Fumaria vaillantii Loisel.) were examined using LC-ESI-MS/MS with a triple quadrupole analyzer. Large differences in the quality and quantity of all analyzed compounds were observed between species of different genera and also within one genus. Two groups of metabolites predominated in the phytochemical profiles. These were isoquinoline alkaloids and, in smaller amounts, non-phenolic carboxylic acids and phenolic compounds. In aerial and underground parts, 22 and 20 compounds were detected, respectively. These included: seven isoquinoline alkaloids: protopine, allocryptopine, coptisine, berberine, chelidonine, sanguinarine, and chelerythrine; five of their derivatives as well as non-alkaloids: malic acid, trans-aconitic acid, quinic acid, salicylic acid, trans-caffeic acid, p-coumaric acid, chlorogenic acid, quercetin, and kaempferol; and vanillin. The aerial parts were much richer in phenolic compounds regardless of the plant species. Characterized extracts were studied for their antimicrobial potential against planktonic and biofilm-producing cells of S. aureus, P. aeruginosa, and C. albicans. The impact of the extracts on cellular metabolic activity and biofilm biomass production was evaluated. Moreover, the antimicrobial activity of the extracts introduced to the polymeric carrier made of bacterial cellulose was assessed. Extracts of C. cheilanthifolia were found to be the most effective against all tested human pathogens. Multiple regression tests indicated a high antimicrobial impact of quercetin in extracts of aerial parts against planktonic cells of S. aureus, P. aeruginosa, and C. albicans, and no direct correlation between the composition of other bioactive substances and the results of antimicrobial activity were found. Conclusively, further investigations are required to identify the relations between recognized and unrecognized compounds within extracts and their biological properties.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Produtos Biológicos/farmacologia , Papaveraceae/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Biofilmes/crescimento & desenvolvimento , Produtos Biológicos/química , Avaliação Pré-Clínica de Medicamentos , Extratos Vegetais/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
19.
Molecules ; 26(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443590

RESUMO

Biocompatible skin wound dressing materials with long-term therapeutic windows and anti-infection properties have attracted great attention all over the world. The cooperation between essential oil and non-toxic or bio-based polymers was a promising strategy. However, the inherent volatility and chemical instability of most ingredients in essential oils make the sustained pharmacological activity of essential oil-based biomaterials a challenge. In this study, a kind of film nanocomposite loaded with patchouli essential oil (PEO-FNC) was fabricated. PEO-loaded mesoporous silica nanoparticles (PEO-MSNs) with drug load higher than 40 wt% were firstly prepared using supercritical CO2 cyclic impregnation (SCCI), and then combined with the film matrix consisting of polyvinyl alcohol and chitosan. The morphology of PEO-MSNs and PEO-FNC was observed by transmission and scanning electron microscope. The mechanical properties, including hygroscopicity, tensile strength and elongation at break (%), were tested. The release behavior of PEO from the film nanocomposite showed that PEO could keep releasing for more than five days. PEO-FNC exhibited good long-term (>48 h) antibacterial effect on Staphylococcus aureus and non-toxicity on mouse fibroblast (L929 cells), making it a promising wound dressing material.


Assuntos
Bandagens/microbiologia , Dióxido de Carbono/química , Nanocompostos/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Pogostemon/química , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Camundongos , Staphylococcus aureus/efeitos dos fármacos
20.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360764

RESUMO

This paper presents the results of structure-activity relationship (SAR) studies of 140 3,3'-(α,ω-dioxaalkan)bis(1-alkylimidazolium) chlorides. In the SAR analysis, the dominance-based rough set approach (DRSA) was used. For analyzed compounds, minimum inhibitory concentration (MIC) against strains of Staphylococcus aureus and Pseudomonas aeruginosa was determined. In order to perform the SAR analysis, a tabular information system was formed, in which tested compounds were described by means of condition attributes, characterizing the structure (substructure parameters and molecular descriptors) and their surface properties, and a decision attribute, classifying compounds with respect to values of MIC. DRSA allows to induce decision rules from data describing the compounds in terms of condition and decision attributes, and to rank condition attributes with respect to relevance using a Bayesian confirmation measure. Decision rules present the most important relationships between structure and surface properties of the compounds on one hand, and their antibacterial activity on the other hand. They also indicate directions of synthesizing more efficient antibacterial compounds. Moreover, the analysis showed differences in the application of various parameters for Gram-positive and Gram-negative strains, respectively.


Assuntos
Antibacterianos , Imidazóis , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Antibacterianos/química , Antibacterianos/farmacologia , Imidazóis/química , Imidazóis/farmacologia , Relação Estrutura-Atividade
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