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2.
Int J Biol Macromol ; : 132631, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38810852

RESUMO

A new series of chromone and furochromone-based sulfonamide Schiff's base derivatives 3-12 were synthesized and evaluated for their antimicrobial activity against S. aureus, E. coli, C. albicans, and A. niger using agar diffusion method. Compound 3a demonstrated potent antimicrobial activities with MIC values of 9.76 and 19.53 µg/mL against S. aureus, E. coli and C. albicans, which is 2-fold and 4-fold more potent than neomycin (MIC = 19.53, 39.06 µg/mL respectively). To improve the effectiveness of 3a, it was encapsulated into chitosan nanoparticles (CS-3aNPs). The CS-3aNPs size was 32.01 nm, as observed by transmission electron microscope (TEM) images and the zeta potential value was 14.1 ±â€¯3.07 mV. Encapsulation efficiency (EE) and loading capacity (LC) were 91.5 % and 1.6 %, respectively as indicated by spectral analysis. The CS-3aNPs extremely inhibited bacterial growth utilizing the colony-forming units (CFU). The ability of CS-3aNPs to protect skin wounds was evaluated in vivo. CS-3aNPs showed complete wound re-epithelialization, hyperplasia of the epidermis, well-organized granulation tissue formation, and reduced signs of wound infection, as seen through histological assessment which showed minimal inflammatory cells in comparison with untreated wound. Overall, these findings suggest that CS-3aNPs has a positive impact on protecting skin wounds from infection due to their antimicrobial activity.

3.
Sci Rep ; 14(1): 9106, 2024 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643226

RESUMO

Coumarins are heterocycles of great interest in the development of valuable active structures in chemistry and biological domains. The ability of coumarins to inhibit biofilm formation of Gram positive bacterium (Staphylococcus aureus), Gram negative bacterium (Escherichia coli) as well as the methicillin-resistant S. aureus (MRSA) has been previously described. In the present work, new hybrid coumarin-heterocycles have been synthesized via the reaction of coumarin-6-sulfonyl chloride and 6-aminocoumarin with different small heterocycle moieties. The biological efficacy of the new compounds was evaluated towards their ability to inhibit biofilm formation and their anti-inflammatory properties. The antimicrobial activities of the newly synthesized compounds were tested against Gram positive bacterium (S. aureus ATCC 6538), Gram negative bacterium (E. coli ATCC 25922), yeast (Candida albicans ATCC 10231) and the fungus (Aspergillus niger NRRL-A326). Compounds 4d, 4e, 4f, 6a and 9 showed significant MIC and MBC values against S. aureus, E. coli, C. albicans, and methicillin-resistant S. aureus (MRSA) with especial incidence on compound 9 which surpasses all the other compounds giving MIC and MBC values of (4.88 and 9.76 µg/mL for S. aureus), (78.13 and 312.5 µg/mL for E. coli), (9.77 and 78.13 µg/mL for C. albicans), and (39.06 and 76.7 µg/mL for MRSA), respectively. With reference to the antibiofilm activity, compound 9 exhibited potent antibiofilm activity with IC50 of 60, 133.32, and 19.67 µg/mL against S. aureus, E. coli, and MRSA, (respectively) considering the reference drug (neomycin). Out of all studied compounds, the anti-inflammatory results indicated that compound 4d effectively inhibited nitric oxide production in lipopolysaccharide-(LPS-) stimulated RAW264.7 macrophage cells, giving NO% inhibition of 70% compared to Sulindac (55.2%).


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus , Escherichia coli , Bactérias Gram-Positivas , Bactérias Gram-Negativas , Cumarínicos/farmacologia , Inflamação/tratamento farmacológico , Biofilmes , Anti-Inflamatórios/farmacologia , Testes de Sensibilidade Microbiana
4.
J Fluoresc ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38647963

RESUMO

Highly solid-state fluorescent dyes based on phenothiazine bearing sulfa-drug derivatives were successfully prepared and fully characterized by NMR, mass spectra, and elemental analysis. The prepared phenothiazine dyes bearing sulfadiazine and sulfathiazole 4-(((10-hexyl-10 H-phenothiazin-3-yl)methylene)amino)-N-(pyrimidin-2yl) benzenesulfonamide (PTZ-1) and 4-(((10-hexyl-10 H-phenothiazin-3-yl) methylene) amino)-N-(thiazol-2-yl)benzenesulfonamide (PTZ-2), showed strong emission in polycrystalline form, and significant emission in solution was observed. The quantum yield of the prepared dyes varied and decreased by increasing the solvent polarity, with the maximum recorded value being 0.63 and 0.6 in dioxane. Aggregation-induced emission (AIE) and the effect of the solvent polarity on absorption and emission spectra were investigated. The dyeing application of polyester fabrics using the prepared phenothiazine-based dyes was studied, showing very good affinity to dyed fabrics. The antibacterial affinity against gram-positive and gram-negative bacteria for the dye powder as well as the dyed PET fabric was investigated, with PTZ-2 showing better affinity against bacteria compared to PTZ-1. This multifunctional property highlights the potential uses of PTZ-1 and PTZ-2 for advanced applications in biomedicine and optoelectronics.

5.
J Enzyme Inhib Med Chem ; 39(1): 2311157, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38348846

RESUMO

Novel coumarin derivatives were synthesised and tested for their cytotoxicity against human cancer cells (PC-3 and MDA-MB-231). Compounds 5, 4b, and 4a possessed potent cytotoxic activity against PC-3 cells with IC50 3.56, 8.99, and 10.22 µM, respectively. Compound 4c displayed cytotoxicity more than erlotinib in the MDA-MB-231 cells with IC50 8.5 µM. Moreover, compound 5 exhibited potent inhibitory activity on EFGR with IC50 0.1812 µM, as well as PI3Kß inhibitory activity that was twofold higher than LY294002, suggesting that this compound has a dual EGFR and PI3Kß inhibiting activity. Docking aligns with the in vitro results and sheds light on the molecular mechanisms underlying dual targeting. Furthermore, compound 5 decreased AKT and m-TOR expression in PC-3 cells, showing that it specifically targets these cells via the EGFR/PI3K/Akt/m-TOR signalling pathway. Simultaneously, compound 5 caused cell cycle arrest at S phase and induced activation of both intrinsic and extrinsic apoptotic pathways.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Apoptose , Receptores ErbB/metabolismo , Cumarínicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Estrutura Molecular
6.
Int J Biol Macromol ; 261(Pt 2): 129801, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309410

RESUMO

This work aims to enhance the performance of the polyvinyl alcohol (PVA) composite by using cellulose nanocrystal (CNC) as reinforcement and copper nanoparticles (CuNPs)/reduced graphene oxide (rGO) as conducting and antimicrobial reagents. Firstly, rGO was loaded onto CuNPs using an eco-friendly microwave method. Different techniques characterized the components and prepared composites, which indicated the incorporation of cellulose nanocrystals and rGO@CuNPs within the polyvinyl alcohol matrix. Utilizing the clear zone of inhibition, the antibacterial test was quantified. Compared to the neat composite, the rGO@CuNPs loaded polyvinyl alcohol/ cellulose nanocrystal composites exhibited no bacterial growth against S. aureus, E. coli, and C. albicans. However, all composites did not have antifungal activity against A. niger. The combination of conductivity and interfacial polarization is the reason for the abrupt increase of permittivity with decreasing frequency. Besides, adding rGO@CuNPs improved the electrical conductivity. DC-Conductivity increased about a decade after adding cellulose nanocrystal to polyvinyl alcohol, then another decade after adding CuONPs. The electric loss modulus representation shows a systematic shift in the peak position towards higher frequencies, decreasing the so-called conductivity relaxation time. This is the main reason for the enhancement of conductivity. The systematic attenuation of peaks' height with increasing conductivity is still unclear.


Assuntos
Grafite , Nanocompostos , Nanopartículas , Álcool de Polivinil/química , Celulose/química , Escherichia coli , Staphylococcus aureus , Nanocompostos/química , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/química
7.
Folia Microbiol (Praha) ; 69(1): 221-234, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37691075

RESUMO

Laccase-producing fungus (MY3) was successfully isolated from soil samples collected from Mansoura Governorate, Egypt. This fungal isolate has shown a high laccase production level over other isolated fungi. The identity of this isolate was determined by the molecular technique 18SrRNA as Curvularia lunata MY3. The enzyme purification was performed using ammonium sulfate precipitation followed by Sephacryl S-200 and DEAE-Sepharose column chromatography. The denatured enzyme using SDS-PAGE had a molar mass of 65 kDa. The purified laccase had an optimum temperature at 40 °C for enzyme activity with 57.3 kJ/mol activation energy for 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) oxidation. The enzyme had an optimum pH of 5.0, and it has shown a high stability at the acidic range (4.5 to 5.5). Mn2+ and Mg2+ ions enhanced the enzyme activity, while most of the enzyme activity was inhibited by Hg2+. Some compounds such as 2-mercaptoethanol, L-cysteine, and sodium azide at a concentration of 10 mmol/L had shown a high suppression effect on the enzyme activity. The enzyme strongly oxidized ABTS and syringaldazine and moderately oxidized DMP and guaiacol. The antimicrobial activity of the purified enzyme towards three pathogenic strains (Escherichia coli ATCC-25922, Staphylococcus aureus NRRLB-767, and Candida albicans ATCC-10231) was evaluated for the potential use as an antimicrobial therapeutic enzyme.


Assuntos
Anti-Infecciosos , Compostos Azo , Benzotiazóis , Curvularia , Lacase , Ácidos Sulfônicos , Lacase/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , Estabilidade Enzimática , Especificidade por Substrato
8.
AMB Express ; 13(1): 107, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789186

RESUMO

Aspergillus terreus has been reported to produce many bioactive metabolites that possess potential activities including anti-inflammatory, cytotoxic, and antimicrobial activities. In the present study, we report the isolation and identification of A. terreus from a collected soil sample. The metabolites existing in the microbial ethyl acetate extract were tentatively identified by HPLC/MS and chemically categorized into alkaloids, terpenoids, polyketides, γ-butyrolactones, quinones, and peptides. In addition, a new triglyceride (1) and a diketopiperazine derivative namely asterrine (4), together with two known butyrolactone (2-3) were purified from the extract. The chemical skeleton of the purified compounds was established by comprehensive analysis of their ESI/MS, 1 and 2D-NMR data. The extract and compounds 3,4 exhibited a strong inhibitory activity for the binding of ACE2 to SARS-CoV-2 spike-protein receptor with IC50 7.4, 9.5, and 8.5 µg/mL, respectively. In addition, the extract, 1 and 2 displayed a potent anti-inflammatory effect with IC50 51.31 and 37.25 pg/mL (Il-6) and 87.97, 68.22 pg/mL (TNF-α), respectively, in comparison to LPS control. In addition, the extract and compound 4 displayed an antimicrobial effect towards S. aureus by MIC 62.5 and 125 µg/mL, while the extract exhibited a potent effect against C. albicans (MIC of 125 µg/mL). Collectively, our data introduce novel bioactivities for the secondary metabolites produced by the terrestrial fungus Aspergillus terreus.

9.
ACS Omega ; 8(20): 17948-17965, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37251193

RESUMO

Microbial DNA gyrase is regarded as an outstanding microbial target. Hence, 15 new quinoline derivatives (5-14) were designed and synthesized. The antimicrobial activity of the afforded compounds was pursued via in vitro approaches. The investigated compounds displayed eligible MIC values, particularly against G-positive Staphylococcus aureus species. Consequently, an S. aureus DNA gyrase supercoiling assay was performed, using ciprofloxacin as a reference control. Obviously, compounds 6b and 10 unveiled IC50 values of 33.64 and 8.45 µM, respectively. Alongside, ciprofloxacin exhibited an IC50 value of 3.80 µM. Furthermore, a significant docking binding score was encountered by compound 6b (-7.73 kcal/mol), surpassing ciprofloxacin (-7.29 kcal/mol). Additionally, both compounds 6b and 10 revealed high GIT absorption without passing the blood brain barrier. Finally, the conducted structure-activity relationship study assured the usefulness of the hydrazine moiety as a molecular hybrid for activity either in cyclic or opened form.

10.
Int J Biol Macromol ; 241: 124632, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37119918

RESUMO

The limited usage of chitosan as a dye adsorbent is attributed to its compact structure and low swelling ability, despite its exceptional properties. The present study aimed to prepare novel chitosan/pyrazole Schiff base (ChS) adsorbents enriched with greenly synthesized zinc oxide nanoparticles. The preparation of ZnO-NPs was carried out through a green approach using the Coriandrum sativum extract. The presence of ZnO-NPs at the nanoscale was validated through TEM, DLS and XRD analyses. FTIR and 1H NMR confirmed the successful preparation of the Schiff base and its ZnO-NPs adsorbents. The incorporation of ZnO-NPs improved the thermal, swelling and antimicrobial properties of the chitosan Schiff base. In addition, a significant improvement in the adsorption of Maxilon Blue dye from its aqueous solution by the Schiff base/ZnO-NPs adsorbent was achived. The prepared ChS/ZnO-NPs adsorbent has the potential to be used as an alternative to conventional adsorbents for the removal of dyes from wastewater.


Assuntos
Quitosana , Nanopartículas , Óxido de Zinco , Corantes/química , Quitosana/química , Óxido de Zinco/química , Águas Residuárias , Bases de Schiff , Nanopartículas/química
11.
Front Pharmacol ; 13: 1006062, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313355

RESUMO

Prostate cancer (PCa) ranks as one of the most commonly diagnosed malignancies worldwide. Toxicity, lack of clinical efficacy, and development of resistance phenotypes are the main challenges in the control of prostate malignancies. Notably, castration-resistance prostate cancer (CRPCa) is a highly aggressive and metastatic phenotype of the disease with a poor prognosis and very limited therapeutic options. Herein, we report the isolation and genotypic identification of a soil-derived fungus Aspergillus neoniveus using the PCR-based internal transcribed spacer (ITS) region amplification approach. HPLC/MS investigation of the metabolic profile of the ethyl acetate extract from the fungal biomass revealed tentative identification of forty-five compounds belonging to various chemical classes including γ-butyrolactones, alkaloids, phenolics, and quinoids. Furthermore, the chromatographic purification of microbial extract enabled the identification of nervonic acid methyl ester (1) for the first time from endophytic fungi, as well as acetyl aszonalenin (2), and butyrolactone II (3) for the first time from A. neoniveus. The chemical frameworks of the isolated compounds were identified via extensive spectral analysis including 1 and 2D NMR and MS. The X-ray crystal structure and absolute configuration of acetyl aszonalenin (2) were also determined. Additionally, screening of in vitro anticancer activity of the fungal extract revealed its potential antiproliferative and anti-migratory activities against five different prostate cancer cells (PC3, PC-3M, DU-145, CWR-R1ca, and 22Rv1), including different cells with the castration-resistance phenotype. Moreover, the isolated metabolites significantly inhibited the proliferation, migration, and colonization of human prostate cancer cells at low micromolar levels, thus providing credence for future investigation of these metabolites in relevant anti-prostate cancer animal models. Furthermore, computational target prediction tools identified the cannabinoid G-protein coupled receptors type 1 (CB1) as a potential biological target mediating, at least in part, the anticancer effects of acetylaszonalenin (2). Moreover, molecular modeling and docking studies revealed a favorable binding pose at the CB1 receptor orthosteric ligand pocket aided by multiple polar and hydrophobic interactions with critical amino acids. In conclusion, the Aspergillus neoniveus-derived prenylated indole alkaloid acetylaszonalenin has promising anticancer activity and is amenable to further hit-to-lead optimization for the control of prostate malignancies via modulating CB1 receptors.

12.
Int J Biol Macromol ; 212: 294-302, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35605720

RESUMO

Despite the outstanding characteristics of alginate, it suffers from bad UV-barrier, water barrier, and antimicrobial properties limiting its wide usage in food packaging. For this concern, Box-Behnken design (BBD) was applied to prepare an alginate-based edible coating of the best optimized UV-shielding properties upon the incorporation of both Aloe vera (AV) and zinc oxide nanoparticles (ZnO-NPs). The optimized minimum UV-transmittance was 4.96% when the optimized compositions of alginate (1.05 g), AV (2.95 g), and ZnO-NPs (4.93 wt%) were used. FTIR was used to verify the successful edible coating preparation while the wide-angle X-ray diffraction (XRD) was used to identify the interactions between the film's components. The incorporation of both AV and ZnO-NPs significantly improved alginate's thermal, water vapor permeability (WVP), mechanical and antimicrobial properties. In addition, the films incorporated with both AV and ZnO-NPs exhibited excellent UV-barrier properties compared with neat alginate. The optimized alginate film incorporated with both ZnO-NPs and AV significantly extended the shelf-life of tomato fruits up to 16 days without any defects. Due to the outstanding physical, UV-shielding, and antimicrobial properties of the optimized alginate/AV/ZnO-NPs film, it could be used potentially in food packaging industries.


Assuntos
Aloe , Anti-Infecciosos , Filmes Comestíveis , Óxido de Zinco , Alginatos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Embalagem de Alimentos
13.
Luminescence ; 37(5): 854-864, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35304819

RESUMO

The target of our current work was designed to prepare titanium oxide doped silver nanoparticles (Ag/TiO2 NPs) and their impact on the functionalization of cotton fabrics. Additionally, the effect of Ag/TiO2 NPs was compared with the individually prepared silver nanoparticles (AgNPs) and titanium oxide nanoparticles (TiO2 NPs). In this work, AgNPs were prepared in the solid state using arabic gum as efficient stabilizing and reducing agent. Then, two concentrations of the as-synthesized nanoparticles were used to functionalize the cotton fabrics by pad-dry-cure treatment in the presence of fixing agent to increase the durability of treated cotton fabrics against vigorous washing cycles. The findings implied that the as-prepared nanoparticles were successfully synthesized in nano-size with spherical shape and homogeneity. The efficacy of the functionalized cotton fabrics with those nanoparticles were evaluated in terms of multifunctional properties including antimicrobial and ultraviolet protection factor (UPF) and the mechanical features before and after many washing cycles; 10, 15 and 20 times. The resultant also proved that Ag/TiO2 NPs-treated cotton fabrics exhibited the greater values of both antimicrobial and UPF properties with enhancement in the tensile strength and elongation features. Thus, the combination between these two nanoparticles through doping reaction is suitable for imparting superior antimicrobial properties against the four tested microbial species (Staphylococcus aureus, Escherichia coli, Candida albicans, and Aspergillus niger) and good UPF properties. Depending on the promising obtained results of the multi-finishing fabrics, these nanoparticles of Ag/TiO2 NPs can be applied for the production of an efficient medical clothes for doctors, nurses and bed sheets for patients in order to kill and prevent the spread of bacteria and then, reduce the transmission of infection to others.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Fibra de Algodão , Escherichia coli , Humanos , Prata/farmacologia , Titânio
14.
Colloids Surf B Biointerfaces ; 211: 112304, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34959094

RESUMO

The objective of this study was to prepare and evaluate Nystatin (NYS) loaded transfersomes to achieve better treatment of vulvovaginal candidiasis. Nystatin transferosomes were formulated utilizing thin film hydration method. A 32 full factorial design was employed to evaluate the effect of different formulation variables. Two independent variables were chosen; the ratio between lecithin surfactant (X1) was set at three levels (10-40), and the type of surfactants (X2) was set at three levels (Span 60, Span 85 and Pluronic F-127). The dependent responses were; entrapment efficiency (Y1: EE %), vesicles size (Y2: VS) and release rate (Y3: RR). Design Expert® software was utilized to statistically optimize formulation variables. The vesicles revealed high NYS encapsulation efficiency ranging from 97.35 ± 0.03 to 98.01 ± 0.20% whereas vesicle size ranged from 194.8 ± 20.42 to 400.8 ± 42.09 nm. High negative zeta potential values indicated good stability of the prepared formulations. NYS release from transfersomes was biphasic and the release pattern followed Higuchi's model. The optimized formulation (F7) exhibited spherical morphology under transmission electron microscopy (TEM). In-vitro and in-vivo antifungal efficiency studies revealed that the optimized formula F7 exhibited significant eradication of candida infestation in comparison to free NYS. The results revealed that the developed NYS transfersomes could be a promising drug delivery system to enhance antifungal efficacy of NYS.


Assuntos
Candidíase Vulvovaginal , Nistatina , Candidíase Vulvovaginal/tratamento farmacológico , Portadores de Fármacos , Humanos , Lipossomos , Nistatina/farmacologia , Tamanho da Partícula , Estudos Prospectivos
15.
Int J Biol Macromol ; 190: 837-844, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517032

RESUMO

The applications of edible coatings stemmed exclusively from alginate in food packaging are restricted due to their inherent deficient antimicrobial, barrier, and UV-barrier properties. In this work, we aimed to design smart alginate-based coatings for active food packaging through the addition of both aloe vera (AV) and garlic oil (GO). The interactions between the film components were verified by FTIR and XRD. Thermal and mechanical properties were improved by the presence of AV and GO. The presence of AV and GO did not significantly influence the transparency of alginate films. The films exhibited a significant UV-shielding to all UV regions. Water vapor permeability was significantly (p < 0.05) reduced either through the incorporation of AV or GO. The antimicrobial properties of the prepared films were considerably improved by the presence of AV and GO. The shelf-life of tomatoes (Solanum lycopersicum L.) was extended when coated with the alginate film incorporated with AV and GO. Owing to the outstanding UV-shielding, mechanical, thermal, and antimicrobial properties, the alginate/AV/GO active coatings could potentially be implemented in the food packaging industry.


Assuntos
Alginatos/química , Filmes Comestíveis , Embalagem de Alimentos , Aloe/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cor , Fungos/efeitos dos fármacos , Alho/química , Testes de Sensibilidade Microbiana , Permeabilidade , Óleos de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Termogravimetria , Raios Ultravioleta , Difração de Raios X
16.
Polymers (Basel) ; 13(12)2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34205409

RESUMO

Anise oil was prepared in its nanoemulsion form to facilitate the penetration of microbial walls, causing microbe mortality. The penetration occurred easily owing to the reduction in its size (nm). Nanoemulsions with different concentrations of anise oil were prepared using lecithin as an emulsifying agent with the aid of an ultra-sonification process. Their morphological and chemical properties were then characterized. The promising constituents were l-Menthone (11.22%), Gurjunene (6.78%), Geranyl acetate (4.03%), Elemene (3.93%), Geranyl tiglate (3.53%), geraniol (3.48%), linalool (0.17%) as well as camphene (0.12%). Different concentrations of prepared anise oil in micro and nanoemulsions were tested as antimicrobial agents against Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), yeast (Candida albicans) and fungi (Asperigillus niger). The findings illustrated that the anise oil-based nanoemulsion exhibited better results. Different biochemical and biological evaluations of anise oil nanoemulsions were conducted, including determining killing times, antioxidant activities (using three different methods), and total phenolics. A trial to estimate the mode of action of anise oil-based nanoemulsion as an antimicrobial agent against S. aureus and C. albicans was performed via studying the release of reducing sugars and protein and conducting scanning electron microscopy.

17.
Molecules ; 26(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34299385

RESUMO

An efficient and simple protocol for the synthesis of a new class of diverse bis(indolyl)pyridines analogues of the marine alkaloid nortopsentin has been reported. A one-pot four-component condensation of 3-cyanocarbomethylindole, various aldehyde, 3-acetylindole, and ammonium acetate in glacial acetic acid led to the formation of 2,6-bis(1H-indol-3-yl)-4-(substituted-phenyl)pyridine-5-carbonitriles. Additionally, 2,6-bis(1H-indol-3-yl)-4-(benzofuran) pyridine-5-carbonitriles were prepared via a one-pot four-component condensation of 3-cyanocarbomethylindole, various N-substituted-indole-3-aldehydes, 2-acetylbenzofuran, and ammonium acetate. The synthesized compounds were evaluated for their ability to inhibit biofilm formation against the Gram-positive bacterial reference strains Staphylococcus aureus ATCC 6538 and the Gram-negative strain Escherichia coli ATCC 25922. Some of the new compounds showed a marked selectivity against the Gram-positive and Gram-negative strains. Remarkably, five compounds 4b, 7a, 7c, 7d and 8e demonstrated good antibiofilm formation against S. aureus and E. coli. On the other hand, the release of reducing sugars and proteins from the treated bacterial strains over the untreated strains was considered to explain the disruption effect of the selected compound on the contact cells of S. aureus and E. coli. Out of all studied compounds, the binding energies and binding mode of bis-indole derivatives 7c and 7d were theoretically the best thymidylate kinase, DNA gyrase B and DNA topoisomerase IV subunit B inhibitors.


Assuntos
Alcaloides/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Inibidores Enzimáticos/farmacologia , Indóis/química , Biofilmes/efeitos dos fármacos , DNA Girase/química , DNA Topoisomerase IV/antagonistas & inibidores , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Núcleosídeo-Fosfato Quinase/antagonistas & inibidores , Piridinas/química
18.
World Neurosurg ; 152: e235-e240, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34058357

RESUMO

BACKGROUND: One of the most preventable errors of a surgeon's career is operating on the incorrect surgical site (ICSS). No study in any specialty has ever investigated the incidence of ICSS events in lower-income countries. This study focuses on identifying the occurrence of these events along with an analysis of potential causes leading to these unfortunate events. METHODS: The authors distributed a survey to neurosurgical colleagues from around the world. These surgeons were first asked to identify details about their practice and incidence and personal experience with ICSS in their own careers. At the end of the survey, they responded to questions about their knowledge of safety checklists. RESULTS: In this study there was a 63.4% response rate. When combined with those who participated through various social media platforms, there were 178 responses. The incidence rate for every 10,000 cases performed was found to be 22.8 in the cranial group, 88.6 in the cervical group, and 158.8 in the lumbar procedural group. This study identified that 40% of participants had never learned or experienced the ABCD time-out strategy and that 60% of surgeons did not use intraoperative navigation or imaging in their practices. The error has never been disclosed to the patient in 48% of the ICSS cases. CONCLUSIONS: Due to a lack of application of safety checklist protocol, there is an increased occurrence of ICSS events in lower-income countries. The results of this study demonstrate the necessity of investing time and resources dedicated to avoiding preventable errors.


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Erros Médicos/estatística & dados numéricos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Encéfalo/cirurgia , Vértebras Cervicais/cirurgia , Lista de Checagem , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Incidência , Vértebras Lombares/cirurgia , Erros Médicos/prevenção & controle , Neuronavegação , Neurocirurgiões , Cirurgia Assistida por Computador , Inquéritos e Questionários
19.
Nanomaterials (Basel) ; 11(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567743

RESUMO

Medical textiles have played an increasingly important protection role in the healthcare industry. This study was aimed at improving the conventional cotton gauze for achieving advanced biomedical specifications (coloration, UV-protection, anti-inflammation, and antimicrobial activities). These features were obtained by modifying the cotton gauze fabrics via in-situ precipitation of hydroxyapatite nanoparticles (HAp NP), followed by in-situ photosynthesis of silver (Ag) NPs with ginger oil as a green reductant with anti-inflammation properties. The HAp-Ag NPs coating provides good UV-protection properties. To further improve the HAp and Ag NPs dispersion and adhesion on the surface, the cotton gauze fabrics were modified by cationization with chitosan, or by partial carboxymethylation (anionic modification). The influence of the cationic and anionic modifications and HAp and Ag NPs deposition on the cotton gauze properties (coloration, UV-protection, antimicrobial activities, and water absorption) was thoroughly assessed. Overall, the results indicate that chemical (anionic and cationic) modification of the cotton gauze enhances HAp and Ag NPs deposition. Chitosan can increase biocompatibility and promotes wound healing properties of cotton gauze. Ag NP deposition onto cotton gauze fabrics brought high antimicrobial activities against Candida albicans, Gram-positive and Gram-negative bacteria, and improved UV protection.

20.
Microorganisms ; 8(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096635

RESUMO

Marine endophytic fungi from under-explored locations are a promising source for the discovery of new bioactivities. Different endophytic fungi were isolated from plants and marine organisms collected from Wadi El-Natrun saline lakes and the Red Sea near Hurghada, Egypt. The isolated strains were grown on three different media, and their ethyl acetate crude extracts were evaluated for their antimicrobial activity against a panel of pathogenic bacteria and fungi as well as their antioxidant properties. Results showed that most of the 32 fungal isolates initially obtained possessed antimicrobial and antioxidant activities. The most potent antimicrobial extracts were applied to three different cellulose containing fabrics to add new multifunctional properties such as ultraviolet protection and antimicrobial functionality. For textile safety, the toxicity profile of the selected fungal extract was evaluated on human fibroblasts. The 21 strains displaying bioactivity were identified on molecular basis and selected for chemical screening and dereplication, which was carried out by analysis of the MS/MS data using the Global Natural Products Social Molecular Networking (GNPS) platform. The obtained molecular network revealed molecular families of compounds commonly produced by fungal strains, and in combination with manual dereplication, further previously reported metabolites were identified as well as potentially new derivatives.

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