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1.
Mymensingh Med J ; 30(2): 478-484, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33830132

RESUMEN

Cosmetic products are often inadequately preserved that provide favourable environment for microbial growth. These emphasize the need for regular investigation of cosmetics in terms of microbial quality and preservative capacity. This study aimed to evaluate the microbial quality, in vitro antibacterial activity and preservative capacity of several popular cosmetics collected from the neighbouring health-care stationary shops in Dhaka city from October 2019 to December 2019. Here, a total of five categories of seven different cosmetic products were subjected to evaluate microbial load, in vitro antibacterial activity and preservative capacity. Among the seven cosmetic products, the viable bacterial count in two cosmetics (All Clear and Sunsilk Shampoo) were found within the acceptable range that was <10³ CFU/ml. None of the cosmetics were found contaminated with fungus and pathogenic organisms. Conversely, three (one Mouthwash and two shampoo) products showed in vitro antibacterial activity against E. coli, S. aureus, Pseudomonas spp., Salmonella spp., Shigella spp. Only single cosmetic product (Cute coconut oil) did not meet the criteria of preservative capacity, while rest six products fulfil the requirements. Thus, our findings revealed a huge load of microorganisms in spite of having adequate preservative capacity in most of the tested products.


Asunto(s)
Antiinfecciosos , Cosméticos , Antiinfecciosos/farmacología , Bangladesh , Cosméticos/farmacología , Escherichia coli , Humanos , Staphylococcus aureus
2.
Int J Nanomedicine ; 16: 1757-1773, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33688190

RESUMEN

Background: NiO nanoparticles have attracted much attention due to their unique properties. They have been synthesized using chemical and physical techniques that often need toxic chemicals. These toxic chemicals cannot easily be removed from the nanoparticle's surface, make them less biocompatible, and limit their biological applications. Instead, plants based green synthesis of nanoparticles uses phytomolecules as reducing and capping agents. These phytomolecules are biologically active with no or less toxic effects. Materials and Methods: Phytomolecules-coated NiO nanoparticles were synthesized employing a green route using Abutilon indicum leaf extract. For comparative study, we also have synthesized NiO nanoparticles using the co-precipitation method. Synthesized nanoparticles were successfully characterized using different spectroscopic techniques. The synthesized nanoparticles were evaluated for antibacterial activity with agar well diffusion assay against different bacteria compared to standard drug and plant extract. They are also examined for anticancer potential using MTT assay against HeLa cancer cells, and further, their antioxidant potential was determined using DPPH assay. Biocompatibility of the synthesized nanoparticles was assessed against fibroblast cells. Results: Phytomolecules-coated NiO nanoparticles were demonstrated superior antibacterial and anticancer performance against bacteria (E. coli, B. bronchiseptica, B. subtilis, and S. aureus) by presenting highest zone of inhibitions (18 ± 0.58 mm, 21 ± 0.45 mm, 22 ± 0.32 mm, and 23 ± 0.77 mm) and HeLa cancer cells by exhibiting the least cell viability percentage (51.74 ± 0.35%) compared to plant extract and chemically synthesized NiO nanoparticles but were comparable to standard antibiotic and anticancer drugs, respectively. Phytomolecules-coated NiO nanoparticles were also demonstrated excellent antioxidant activity (79.87 ± 0.43% DPPH inhibition) and biocompatibility (> 90% cell viability) with fibroblast cells. Conclusion: Nanoparticle synthesis using the Abutilon indicum leaf extract is an efficient and economical method, produces biocompatible and more biologically active nanoparticles, which can be an excellent candidate for therapeutic applications.


Asunto(s)
Antiinfecciosos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Malvaceae/química , Nanopartículas del Metal/química , Fitoquímicos/química , Extractos Vegetales/química , Hojas de la Planta/química , Bacterias/efectos de los fármacos , Compuestos de Bifenilo/química , Fibroblastos/efectos de los fármacos , Tecnología Química Verde , Células HeLa , Humanos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Picratos/química , Espectrometría por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Difracción de Rayos X
3.
Nat Commun ; 12(1): 1500, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33686077

RESUMEN

Diphtheria is a respiratory disease caused by the bacterium Corynebacterium diphtheriae. Although the development of a toxin-based vaccine in the 1930s has allowed a high level of control over the disease, cases have increased in recent years. Here, we describe the genomic variation of 502 C. diphtheriae isolates across 16 countries and territories over 122 years. We generate a core gene phylogeny and determine the presence of antimicrobial resistance genes and variation within the tox gene of 291 tox+ isolates. Numerous, highly diverse clusters of C. diphtheriae are observed across the phylogeny, each containing isolates from multiple countries, regions and time of isolation. The number of antimicrobial resistance genes, as well as the breadth of antibiotic resistance, is substantially greater in the last decade than ever before. We identified and analysed 18 tox gene variants, with mutations estimated to be of medium to high structural impact.


Asunto(s)
Corynebacterium diphtheriae/genética , Toxina Diftérica/genética , Difteria/microbiología , Difteria/prevención & control , Antiinfecciosos/farmacología , Corynebacterium diphtheriae/efectos de los fármacos , Toxoide Diftérico , Farmacorresistencia Bacteriana/genética , Variación Genética , Genoma Bacteriano , Genómica , Humanos , India , Pruebas de Sensibilidad Microbiana , Filogenia , Polimorfismo de Nucleótido Simple
4.
Int J Mol Sci ; 22(4)2021 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-33668523

RESUMEN

Genus Aspergillus represents a widely spread genus of fungi that is highly popular for possessing potent medicinal potential comprising mainly antimicrobial, cytotoxic and antioxidant properties. They are highly attributed to its richness by alkaloids, terpenes, steroids and polyketons. This review aimed to comprehensively explore the diverse alkaloids isolated and identified from different species of genus Aspergillus that were found to be associated with different marine organisms regarding their chemistry and biology. Around 174 alkaloid metabolites were reported, 66 of which showed important biological activities with respect to the tested biological activities mainly comprising antiviral, antibacterial, antifungal, cytotoxic, antioxidant and antifouling activities. Besides, in silico studies on different microbial proteins comprising DNA-gyrase, topoisomerase IV, dihydrofolate reductase, transcriptional regulator TcaR (protein), and aminoglycoside nucleotidyl transferase were done for sixteen alkaloids that showed anti-infective potential for better mechanistic interpretation of their probable mode of action. The inhibitory potential of compounds vs. Angiotensin-Converting Enzyme 2 (ACE2) as an important therapeutic target combating COVID-19 infection and its complication was also examined using molecular docking. Fumigatoside E showed the best fitting within the active sites of all the examined proteins. Thus, Aspergillus species isolated from marine organisms could afford bioactive entities combating infectious diseases.


Asunto(s)
Alcaloides/química , Alcaloides/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Aspergillus/química , /tratamiento farmacológico , /metabolismo , Animales , Antivirales/química , Antivirales/farmacología , Descubrimiento de Drogas , Humanos , Simulación del Acoplamiento Molecular , /fisiología
5.
Food Chem ; 352: 129396, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33652195

RESUMEN

Extracts from 'Zhéri' and 'Hicaznar' varieties of pomegranate, Punica granatum L., were obtained by subjecting powdered peels to extraction using water, water/ethanol (1:1; v/v), ethanol, acetone and heptane. Using the agar diffusion assay, extracts with water and/or ethanol were shown to display significant antimicrobial activity with diameters of inhibition zones up to 20 mm. Ethanolic extracts, which were the most active, were fractionated using SPE, HPLC and UHPLC, and the active compounds they contain were identified by mass spectrometry. Punicalagin, under its α and ß anomeric forms, was identified as the antibacterial compound in pomegranate peel extracts. Both forms were active with MIC values between 0.3 and 1.2 µg.ml-1, and they easily converted from one to the other with an α/ß equilibrium ratio of 3/7. Their spectrum of activity targeted 10 out of 13 Gram positive and two out of three Gram negative bacteria as well as a yeast strain.


Asunto(s)
Antiinfecciosos/farmacología , Taninos Hidrolizables/farmacología , Granada (Fruta)/química , Cromatografía Líquida de Alta Presión , Frutas/química , Pruebas de Sensibilidad Microbiana
6.
Carbohydr Polym ; 260: 117834, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712171

RESUMEN

This study reports preparation and physicochemical characterization of natural antimicrobials (Origanum Syriacum essential oil (OSEO), shrimp chitosan nanoparticles (CSNPs)) and new imidazolium ionic liquid-supported Zn(II)Salen. These antimicrobials were separately or co-encapsulated by CSNPs to fabricate novel antimicrobial nanoplatforms "NPFs" (OSEO-loaded CSNPs (NPF-1), Zn(II)Salen-loaded CSNPs (NPF-2), and Zn(II)Salen@OSEO-loaded CSNPs (NPF-3)). The finding of loading, encapsulation, and antimicrobial release studies confirm the suitability of CSNPs for nanoencapsulation of Zn(II)Salen and OSEO. All NPFs can significantly suppress the growth of microbial species with performances dependent upon the microbial strain and nanoplatform concentration. The susceptibility of microbes toward new antimicrobials was as follows; Gram-positive bacteria > Gram-negative bacteria > fungi. The amazing physicochemical features of new nanoplatforms and their bioactive ingredients (Zn(II)Salen, OSEO, and CSNPs) signify the importance of our designs for developing a new generation of nanopharmaceuticals supported both natural products and biogenic ionic metal cofactors, targeting the multidrug resistant (MDR) pathogens.


Asunto(s)
Antiinfecciosos/química , Quitosano/química , Etilenodiaminas/química , Nanopartículas/química , Aceites Volátiles/química , Antiinfecciosos/metabolismo , Antiinfecciosos/farmacología , Portadores de Fármacos/química , Liberación de Fármacos , Etilenodiaminas/metabolismo , Hongos/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Imidazoles/química , Aceites Volátiles/metabolismo , Origanum/metabolismo , Tamaño de la Partícula , Temperatura , Zinc/química
7.
ACS Appl Mater Interfaces ; 13(11): 12912-12927, 2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33715350

RESUMEN

The current pandemic caused by SARS-CoV-2 has seen a widespread use of personal protective equipment, especially face masks. This has created the need to develop better and reusable protective masks with built-in antimicrobial, self-cleaning, and aerosol filtration properties to prevent the transmission of air-borne pathogens such as the coronaviruses. Herein, molybdenum disulfide (MoS2) nanosheets are used to prepare modified polycotton fabrics having excellent antibacterial activity and photothermal properties. Upon sunlight irradiation, the nanosheet-modified fabrics rapidly increased the surface temperature to ∼77 °C, making them ideal for sunlight-mediated self-disinfection. Complete self-disinfection of the nanosheet-modified fabric was achieved within 3 min of irradiation, making the fabrics favorably reusable upon self-disinfection. The nanosheet-modified fabrics maintained the antibacterial efficiency even after 60 washing cycles. Furthermore, the particle filtration efficiency of three-layered surgical masks was found to be significantly improved through incorporation of the MoS2-modified fabric as an additional layer of protective clothing, without compromising the breathability of the masks. The repurposed surgical masks could filter out around 97% of 200 nm particles and 96% of 100 nm particles, thus making them potentially useful for preventing the spread of coronaviruses (120 nm) by trapping them along with antibacterial protection against other airborne pathogens.


Asunto(s)
Antiinfecciosos/química , Disulfuros/química , Molibdeno/química , Nanoestructuras/química , Equipo de Protección Personal , Reciclaje , Antiinfecciosos/farmacología , /virología , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Glutatión/química , Humanos , Nanoestructuras/toxicidad , Oxidación-Reducción , Tamaño de la Partícula , Especies Reactivas de Oxígeno/metabolismo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/metabolismo , Luz Solar , Temperatura
8.
Molecules ; 26(4)2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669712

RESUMEN

Hydroxyapatite (HA) is the main inorganic mineral that constitutes bone matrix and represents the most used biomaterial for bone regeneration. Over the years, it has been demonstrated that HA exhibits good biocompatibility, osteoconductivity, and osteoinductivity both in vitro and in vivo, and can be prepared by synthetic and natural sources via easy fabrication strategies. However, its low antibacterial property and its fragile nature restricts its usage for bone graft applications. In this study we functionalized a MgHA scaffold with gold nanorods (AuNRs) and evaluated its antibacterial effect against S. aureus and E. coli in both suspension and adhesion and its cytotoxicity over time (1 to 24 days). Results show that the AuNRs nano-functionalization improves the antibacterial activity with 100% bacterial reduction after 24 h. The toxicity study, however, indicates a 4.38-fold cell number decrease at 24 days. Although further optimization on nano-functionalization process are needed for cytotoxicity, these data indicated that Au-NRs nano-functionalization is a very promising method for improving the antibacterial properties of HA.


Asunto(s)
Antiinfecciosos/farmacología , Durapatita/farmacología , Oro/farmacología , Magnesio/farmacología , Nanotubos/química , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Nanotubos/ultraestructura , Espectroscopía de Fotoelectrones , Staphylococcus aureus/efectos de los fármacos , Andamios del Tejido/química
9.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670506

RESUMEN

The aim of this study was to evaluate occurrence of T. pulegioides α-terpinyl acetate chemotype, as source of natural origin α-terpinyl acetate, to determine its phytotoxic and antimicrobial features. Were investigated 131 T. pulegioides habitats. Essential oils were isolated by hydrodistillation and analyzed by GC-FID and GC-MS. Phytotoxic effect of essential oil of this chemotype on monocotyledons and dicotyledons through water and air was carried out in laboratory conditions; the broth microdilution method was used to screen essential oil effect against human pathogenic microorganisms. Results showed that α-terpinyl acetate was very rare compound in essential oil of T. pulegioides: it was found only in 35% of investigated T. pulegioides habitats. α-Terpinyl acetate (in essential oil and pure) demonstrated different behavior on investigated plants. Phytotoxic effect of α-terpinyl acetate was stronger on investigated monocotyledons than on dicotyledons. α-Terpinyl acetate essential oil inhibited seeds germination and radicles growth for high economic productivity forage grass monocotyledon Poa pratensis, but stimulated seed germination for high economic productive forage legume dicotyledon Trifolium pretense. α-Terpinyl acetate essential oil showed high antimicrobial effect against fungi and dermatophytes but lower effect against bacteria and Candida yeasts. Therefore, T. pulegioides α-terpinyl acetate chemotype could be a potential compound for developing preventive measures or/and drugs for mycosis.


Asunto(s)
Antiinfecciosos/farmacología , Aceites Volátiles/química , Terpenos/farmacología , Thymus (Planta)/química , Geografía , Germinación/efectos de los fármacos , Lituania , Pruebas de Sensibilidad Microbiana , Terpenos/química
10.
Molecules ; 26(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671247

RESUMEN

In the present study, naphthyl acetohydrazide (HL) ligand was prepared and used for the synthesis of new six amorphous transition metal (Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II)) complexes. All the compounds were characterized by elemental analysis, UV-vis, FT-IR, 1H- and 13C-NMR, and Matrix-Assisted Laser Desorption Ionization (MALDI). The solubilization study was carried out by estimating the interaction between the metal complexes with surfactants viz. sodium stearate (SS) and Cetyltrimethylammonium bromide (CTAB). UV-Visible spectroscopy was employed to determine partitioning and binding parameters, whereas electrical conductivity measurements were employed to estimate critical micellar concentration (CMC), the extent of dissociation, and free energy of micellization. The CT-DNA interaction of synthesized compounds with DNA represents the major groove binding. The synthesized ligand and metal complexes were also tested against bacterial and fungal strains and it has been observed that Cu(II) complex is active against all the strains except Candida albicans, while Cd(II) complex is active against all bacterial and fungal strains except Pseudomonas. Among all compounds, only the Pd(II) complex shows reasonable activity against cervical cancer HeLa cell lines, representing 97% inhibition.


Asunto(s)
Antiinfecciosos/farmacología , Complejos de Coordinación/síntesis química , ADN/metabolismo , Hidrazonas/síntesis química , Hidrazonas/farmacología , Metales/química , Micelas , Neoplasias/patología , Bacterias/efectos de los fármacos , Espectroscopía de Resonancia Magnética con Carbono-13 , Supervivencia Celular/efectos de los fármacos , Conductividad Eléctrica , Células HeLa , Humanos , Hidrazonas/química , Ligandos , Pruebas de Sensibilidad Microbiana , Espectroscopía de Protones por Resonancia Magnética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Tensoactivos/química
11.
Molecules ; 26(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671275

RESUMEN

Oregano (Origanum vulgare L.) and thyme (Thymus vulgaris L.) have long been known for their organoleptic properties. Both plants are widely used in cuisine worldwide in fresh and dried form and as a pharmaceutical raw material. The study aimed to assess if the type of cultivation influenced chosen chemical parameters (total polyphenols by Folin-Ciocalteu method; carotenoids and chlorophyll content by Lichtenthaler method), antimicrobial activity (with chosen reference microbial strains) and shaped cytotoxicity (with L929 mouse fibroblasts cell line) in water macerates of dry oregano and thyme. Polyphenols content and antimicrobial activity were higher in water macerates obtained from conventional cultivation (independently from herb species), unlike the pigments in a higher amount in macerates from organic herbs cultivation. Among all tested macerates stronger antimicrobial properties (effective in inhibiting the growth of Pseudomonas aeruginosa, Bacillus cereus and Salmonella enteritidis) and higher cytotoxicity (abilities to diminish the growth of L929 fibroblasts cytotoxicity) characterized the conventionally cultivated thyme macerate.


Asunto(s)
Agricultura , Carotenoides/análisis , Clorofila/análisis , Fenoles/análisis , Agua/química , Animales , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular , Ratones , Pruebas de Sensibilidad Microbiana , Origanum/química , Extractos Vegetales , Polifenoles/análisis , Thymus (Planta)/química
12.
Carbohydr Polym ; 260: 117774, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712131

RESUMEN

3D printing, one of its kinds has been a recent technological trend to fabricate complex and patterned biomaterial with controlled precision. With the conventional kick-start of printing metals and plastics, advancements in printing viable cells, polysaccharides or microbes themselves have been achieved. The additive antimicrobial properties in bioinks sourced from organic and inorganic materials have profound implications in tissue engineering. Cellulose, alginate, exopolysaccharides, ceramics and synthetic polymers are integrated as a viable component in inks and used for bio-printing. To date, bacterial infection and immunogenicity pose a potential health risk during a tissue implant or bone substitution. In order to mitigate microbial infection, antimicrobial bioinks with significant antimicrobial potential have been the much sought after strategies. This approach could be an effective frontline defense against microbial interference in tissue engineering and biomedical applications. An overview on the antimicrobial potential of polysaccharides as bioinks for 3D bioprinting has been critically reviewed.


Asunto(s)
Antiinfecciosos/química , Bioimpresión , Tinta , Alginatos/química , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Celulosa/química , Hongos/efectos de los fármacos , Polímeros/química , Polisacáridos Bacterianos/química , Impresión Tridimensional
13.
Carbohydr Polym ; 260: 117777, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712133

RESUMEN

The combination of alginate, hyaluronic acid and multivalent ions have been reported to form alginate-hyaluronic acid ionic-crosslinking hydrogels for biomedical applications. However, injectable alginate-hyaluronic acid ionic-crosslinking hydrogels with satisfactory shear-thinning property have rarely been reported. In this study, we successfully developed an ionic-crosslinked alginate-hyaluronic acid hydrogel by simple assembly of alginate-hyaluronic acid mixture and Fe3+ complex. This hydrogel could fully recover within seconds after damaged, while displayed shear thinning behavior and good injectability which were contributed by the reversible and dynamic metal-ligand interactions formed via ferric ions and carboxyl groups of the polymers. Moreover, the local degradation of this hydrogel giving the hydrogel sustained ferric ions release property, of which led to potential long-term antibacterial activities against multiple types of bacteria including gram-negative Escherichia coli and gram-positive Staphylococcus aureus, as well as representative oral pathogenic bacteria Streptococcus mutans and Porphyromonas gingivalis.


Asunto(s)
Alginatos/química , Antiinfecciosos/química , Compuestos Férricos/química , Ácido Hialurónico/química , Hidrogeles/química , Animales , Antiinfecciosos/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Femenino , Compuestos Férricos/metabolismo , Humanos , Hidrogeles/farmacología , Ratones , Ratones Endogámicos BALB C , Porphyromonas/efectos de los fármacos , Reología , Piel/efectos de los fármacos , Piel/patología , Staphylococcus aureus/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos
14.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652755

RESUMEN

Food packaging is designed to protect foods, to provide required information about the food, and to make food handling convenient for distribution to consumers. Packaging has a crucial role in the process of food quality, safety, and shelf-life extension. Possible interactions between food and packaging are important in what is concerning food quality and safety. This review tries to offer a picture of the most important types of active packaging emphasizing the controlled/target release antimicrobial and/or antioxidant packaging including system design, different methods of polymer matrix modification, and processing. The testing methods for the appreciation of the performance of active food packaging, as well as mechanisms and kinetics implied in active compounds release, are summarized. During the last years, many fast advancements in packaging technology appeared, including intelligent or smart packaging (IOSP), (i.e., time-temperature indicators (TTIs), gas indicators, radiofrequency identification (RFID), and others). Legislation is also discussed.


Asunto(s)
Antiinfecciosos/química , Antioxidantes/química , Preparaciones de Acción Retardada/química , Embalaje de Alimentos , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Preparaciones de Acción Retardada/farmacología , Conservación de Alimentos , Calidad de los Alimentos , Humanos
15.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652788

RESUMEN

Molybdates are biocidal materials that can be useful in coating surfaces that are susceptible to contamination and the spread of microorganisms. The aim of this work was to investigate the effects of copper doping of hydrated cobalt molybdate, synthesized by the co-precipitation method, on its antibacterial activity and to elucidate the structural and morphological changes caused by the dopant in the material. The synthesized materials were characterized by PXRD, Fourier Transformed Infrared (FTIR), thermogravimetric analysis/differential scanning calorimetry (TG/DSC), and SEM-Energy Dispersive Spectroscopy (SEM-EDS). The antibacterial response of the materials was verified using the Minimum Inhibitory Concentration (MIC) employing the broth microdilution method. The size of the CoMoO4·1.03H2O microparticles gradually increased as the percentage of copper increased, decreasing the energy that is needed to promote the transition from the hydrated to the beta phase and changing the color of material. CoMoO4·1.03H2O obtained better bactericidal performance against the tested strains of Staphylococcus aureus (gram-positive) than Escherichia coli (gram-negative). However, an interesting point was that the use of copper as a doping agent for hydrated cobalt molybdate caused an increase of MIC value in the presence of E. coli and S. aureus strains. The study demonstrates the need for caution in the use of copper as a doping material in biocidal matrices, such as cobalt molybdate.


Asunto(s)
Antiinfecciosos/química , Cobalto/química , Cobre/química , Molibdeno/química , Antiinfecciosos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Complejos de Coordinación/química , Escherichia coli/efectos de los fármacos , Humanos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Staphylococcus aureus/efectos de los fármacos
16.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652887

RESUMEN

Although several natural plants and mixtures have been known and used over the centuries for their antibacterial activity, few have been thoroughly explored in the field of dentistry. Thus, the aim of this study was to enhance the antimicrobial activity of a conventional glass ionomer cement (GIC) with natural plant extracts. The effect of this alteration on the bond strength and film thickness of glass ionomer cement was evaluated and related to an 0.5% chlorohexidine modified GIC. Olive leaves (Olea europaea), Fig tree (Ficus carica), and the leaves and roots of Miswak (Salvadora persica) were used to prepare an alcoholic extract mixture. The prepared extract mixture after the evaporation of the solvent was used to modify a freeze-dried glass ionomer cement at three different extracts: water mass ratios 1:2, 1:1, and 2:1. An 0.5% chlorhexidine diacetate powder was added to a conventional GIC for the preparation of a positive control group (CHX-GIC) for comparison. The bond strength to dentine was assessed using a material-testing machine at a cross head speed of 0.5 mm/min. Failure mode was analyzed using a stereomicroscope at 12× magnification. The cement film thickness was evaluated in accordance with ISO standard 9917-1. The minimum number of samples in each group was n = 10. Statistical analysis was performed using a Kruskal-Wallis test followed by Dunn's post hoc test for pairwise comparison. There was a statistically insignificant difference between the median shear bond strength (p = 0.046) of the control group (M = 3.4 MPa), and each of the CHX-GIC (M = 1.7 MPa), and the three plant modified groups of 1:2, 1:1, 2:1 (M = 5.1, 3.2, and 4.3 MPa, respectively). The CHX-GIC group showed statistically significant lower median values compared to the three plant-modified groups. Mixed and cohesive failure modes were predominant among all the tested groups. All the tested groups (p < 0.001) met the ISO standard of having less than 25 µm film thickness, with the 2:1 group (M = 24 µm) being statistically the highest among all the other groups. The plant extracts did not alter either the shear bond strength or the film thickness of the GIC and thus might represent a promising additive to GICs.


Asunto(s)
Antiinfecciosos/química , Cementos Dentales/química , Cementos de Ionómero Vitreo/química , Extractos Vegetales/farmacología , Antiinfecciosos/farmacología , Clorhexidina/química , Clorhexidina/farmacología , Cementos Dentales/farmacología , Dentina/química , Dentina/microbiología , Ficus/química , Cementos de Ionómero Vitreo/farmacología , Humanos , Ensayo de Materiales , Olea/química , Extractos Vegetales/química , Hojas de la Planta/química , Raíces de Plantas/química , Salvadoraceae/química , Resistencia al Corte , Propiedades de Superficie
17.
Small ; 17(12): e2100139, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33656273

RESUMEN

The novel coronavirus SARS-CoV-2 has prompted a worldwide pandemic and poses a great threat to public safety and global economies. Most present personal protective equipment (PPE) used to intercept pathogenic microorganisms is deficient in biocidal properties. Herein, we present green nanofibers with effective antibacterial and antiviral activities that can provide sustainable bioprotection by continuously producing reactive oxygen species (ROS). The superiority of the design is that the nanofibers can absorb and store visible light energy and maintain the activity under light or dark environment. Moreover, the nanofibers can uninterruptedly release ROS in the absence of an external hydrogen donor, acting as a biocide under all weather conditions. A facile spraying method is proposed to rapidly deploy the functional nanofibers to existing PPE, such as protective suits and masks. The modified PPE exhibit stable ROS production, excellent capacity for storing activity potential, long-term durability, and high bactericidal (>99.9%) and viricidal (>99.999%) efficacies.


Asunto(s)
Antiinfecciosos/farmacología , Hidrógeno/química , Luz , Nanofibras/química , Benzofenonas/química , Celulosa/farmacología , Nanofibras/ultraestructura , Riboflavina/farmacología
18.
Nat Commun ; 12(1): 745, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33531505

RESUMEN

Acting by producing reactive oxygen species (ROS) in situ, nanozymes are promising as antimicrobials. ROS' intrinsic inability to distinguish bacteria from mammalian cells, however, deprives nanozymes of the selectivity necessary for an ideal antimicrobial. Here we report that nanozymes that generate surface-bound ROS selectively kill bacteria over mammalian cells. This result is robust across three distinct nanozymes that universally generate surface-bound ROS, with an oxidase-like silver-palladium bimetallic alloy nanocage, AgPd0.38, being the lead model. The selectivity is attributable to both the surface-bound nature of ROS these nanozymes generate and an unexpected antidote role of endocytosis. Though surface-bound, the ROS on AgPd0.38 efficiently eliminated antibiotic-resistant bacteria and effectively delayed the onset of bacterial resistance emergence. When used as coating additives, AgPd0.38 enabled an inert substrate to inhibit biofilm formation and suppress infection-related immune responses in mouse models. This work opens an avenue toward biocompatible nanozymes and may have implication in our fight against antimicrobial resistance.


Asunto(s)
Antibacterianos/farmacología , Antiinfecciosos/química , Nanopartículas/química , Especies Reactivas de Oxígeno/metabolismo , Animales , Antiinfecciosos/farmacología , Biopelículas/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana
19.
Microbiome ; 9(1): 49, 2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33597026

RESUMEN

BACKGROUND: Pathogenic microorganisms cause disease by invading, colonizing, and damaging their host. Virulence factors including bacterial toxins contribute to pathogenicity. Additionally, antimicrobial resistance genes allow pathogens to evade otherwise curative treatments. To understand causal relationships between microbiome compositions, functioning, and disease, it is essential to identify virulence factors and antimicrobial resistance genes in situ. At present, there is a clear lack of computational approaches to simultaneously identify these factors in metagenomic datasets. RESULTS: Here, we present PathoFact, a tool for the contextualized prediction of virulence factors, bacterial toxins, and antimicrobial resistance genes with high accuracy (0.921, 0.832 and 0.979, respectively) and specificity (0.957, 0.989 and 0.994). We evaluate the performance of PathoFact on simulated metagenomic datasets and perform a comparison to two other general workflows for the analysis of metagenomic data. PathoFact outperforms all existing workflows in predicting virulence factors and toxin genes. It performs comparably to one pipeline regarding the prediction of antimicrobial resistance while outperforming the others. We further demonstrate the performance of PathoFact on three publicly available case-control metagenomic datasets representing an actual infection as well as chronic diseases in which either pathogenic potential or bacterial toxins are hypothesized to play a role. In each case, we identify virulence factors and AMR genes which differentiated between the case and control groups, thereby revealing novel gene associations with the studied diseases. CONCLUSION: PathoFact is an easy-to-use, modular, and reproducible pipeline for the identification of virulence factors, bacterial toxins, and antimicrobial resistance genes in metagenomic data. Additionally, our tool combines the prediction of these pathogenicity factors with the identification of mobile genetic elements. This provides further depth to the analysis by considering the genomic context of the pertinent genes. Furthermore, PathoFact's modules for virulence factors, toxins, and antimicrobial resistance genes can be applied independently, thereby making it a flexible and versatile tool. PathoFact, its models, and databases are freely available at https://pathofact.lcsb.uni.lu . Video abstract.


Asunto(s)
Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana/genética , Metagenómica , Programas Informáticos , Factores de Virulencia/genética , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos
20.
Int J Nanomedicine ; 16: 1157-1174, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33623380

RESUMEN

Introduction: Candida albicans is a major opportunistic pathogen that causes a wide range of human infections. Currently available therapeutic agents are limited for treating these fungal infections due to multidrug resistance as well as their nonbiodegradability, poor biocompatibility and toxicity. In order to battle these limitations, we have synthesized a polymeric system as microcarriers to deliver the antifungal drug. The objective of the present study was to immobilize MgO/CuO nanocomposite and nystatin-loaded MgO/CuO nanocomposites in nontoxic, nonimmunogenic, biodegradable and biocompatible sodium alginate microspheres for the first time. Materials and Methods: Nanoparticle-loaded sodium alginate microspheres were prepared by ionotropic gelation technique using calcium chloride as a cross-linker. Synthesized microspheres were characterized using standard characterization techniques and were evaluated for biological activity against MDR strain of C. albicans. Results: Characterization of microspheres by Fourier-transform infrared spectroscopy confirmed loading of Nys-MgO/CuO NPs, scanning electron microscopy (SEM) revealed rough spherical beads with a highly porous surface having an average size in the range of 8-10 µm. X-ray diffraction (XRD) analyzed its semicrystalline structure. Entrapment efficiency of Nys-MgO/CuO NPs was 80% and release kinetic study revealed sustained and prolonged release of drug in pH 5.5. Flow cytometry analysis showed yeast cell death caused by Nys-MgO/CuO MS exhibits late apoptotic features. In cytotoxicity assay 5-14 mg of microspheres did not cause hemolysis. Microspheres reduced virulence traits of C. albicans such as germ tube and biofilm formation were compromised at concentration of 5 mg/mL. Antimicrobial assessment results revealed a pronounced inhibitory effect against C. albicans. Conclusion: The in vitro experiments have shown promising results based on good stability, Nys-MgO/CuO NP-encapsulated microspheres can be used as a prolonged controlled release system against MDR pathogenic C. albicans.


Asunto(s)
Alginatos/química , Candida albicans/patogenicidad , Cobre/química , Resistencia a Múltiples Medicamentos , Óxido de Magnesio/química , Microesferas , Nanocompuestos/química , Nistatina/farmacología , Antiinfecciosos/farmacología , Biopelículas/efectos de los fármacos , Liberación de Fármacos , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Cinética , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Fenotipo , Espectroscopía Infrarroja por Transformada de Fourier , Virulencia/efectos de los fármacos , Factores de Virulencia/metabolismo , Difracción de Rayos X
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