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1.
Molecules ; 26(6)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33806967

RESUMEN

Bats are unique in their potential to serve as reservoir hosts for intracellular pathogens. Recently, the impact of COVID-19 has relegated bats from biomedical darkness to the frontline of public health as bats are the natural reservoir of many viruses, including SARS-Cov-2. Many bat genomes have been sequenced recently, and sequences coding for antimicrobial peptides are available in the public databases. Here we provide a structural analysis of genome-predicted bat cathelicidins as components of their innate immunity. A total of 32 unique protein sequences were retrieved from the NCBI database. Interestingly, some bat species contained more than one cathelicidin. We examined the conserved cysteines within the cathelin-like domain and the peptide portion of each sequence and revealed phylogenetic relationships and structural dissimilarities. The antibacterial, antifungal, and antiviral activity of peptides was examined using bioinformatic tools. The peptides were modeled and subjected to docking analysis with the region binding domain (RBD) region of the SARS-CoV-2 Spike protein. The appearance of multiple forms of cathelicidins verifies the complex microbial challenges encountered by these species. Learning more about antiviral defenses of bats and how they drive virus evolution will help scientists to investigate the function of antimicrobial peptides in these species.


Asunto(s)
Catelicidinas/química , Catelicidinas/farmacología , Quirópteros/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Antivirales/química , Antivirales/farmacología , Sitios de Unión , Catelicidinas/genética , Catelicidinas/metabolismo , Biología Computacional/métodos , Simulación por Computador , Genoma , Simulación del Acoplamiento Molecular , Filogenia
2.
Molecules ; 26(6)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33807029

RESUMEN

Natural products are gaining more interest recently, much of which focuses on those derived from medicinal plants. The common chicory (Cichorium intybus L.), of the Astraceae family, is a prime example of this trend. It has been proven to be a feasible source of biologically relevant elements (K, Fe, Ca), vitamins (A, B1, B2, C) as well as bioactive compounds (inulin, sesquiterpene lactones, coumarin derivatives, cichoric acid, phenolic acids), which exert potent pro-health effects on the human organism. It displays choleretic and digestion-promoting, as well as appetite-increasing, anti-inflammatory and antibacterial action, all owing to its varied phytochemical composition. Hence, chicory is used most often to treat gastrointestinal disorders. Chicory was among the plants with potential against SARS-CoV-2, too. To this and other ends, roots, herb, flowers and leaves are used. Apart from its phytochemical applications, chicory is also used in gastronomy as a coffee substitute, food or drink additive. The aim of this paper is to present, in the light of the recent literature, the chemical composition and properties of chicory.


Asunto(s)
Achicoria/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Antiparasitarios/química , Antiparasitarios/farmacología , Antivirales/química , Antivirales/farmacología , Achicoria/fisiología , Culinaria , Hipersensibilidad a los Alimentos/etiología , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Plantas Medicinales/química
3.
AAPS PharmSciTech ; 22(3): 108, 2021 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-33718989

RESUMEN

The combination of self-microemulsifying drug delivery system (SMEDDS) and mesoporous silica materials favors the oral delivery of poorly water-soluble drugs (PWSD). However, the influence of the surface property of the mesopores towards the drug release and in vivo pharmacokinetics is still unknown. In this study, SBA-15 with hydroxyl groups (SBA-15-H), methyl groups (SBA-15-M), amino groups (SBA-15-A), or carboxyl groups (SBA-15-C) was combined with SMEDDS containing sirolimus (SRL). The diffusion and self-emulsifying of SMEDDS greatly improved the drug release over the raw SRL and SRL-SBA-15-R (R referred to as the functional groups). Results of drug absorption and X-ray photoelectron spectroscopy (XPS) showed strong hydrogen binding between SRL and the amino groups of SBA-15-A, which hindered the drug release and oral bioavailability of SRL-SMEDDS-SBA-15-A. The favorable release of SRL-SMEDDS-SBA-15-C (91.31 ± 0.57%) and SRL-SMEDDS-SBA-15-M (91.76 ± 3.72%) contributed to enhancing the maximum blood concentration (Cmax) and the area under the concentration-time curve (AUC0→48). In conclusion, the release of SRL-SMEDDS-SBA-15-R was determined by the surface affinity of the SBA-15-R and the interaction between the SRL molecules and the surface of SBA-15-R. This study suggested that the SMEDDS-SBA-15 was a favorable carrier for PWSD, and the surface property of the mesopores should be considered for the optimization of the SMEDDS-SBA-15.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/fisiología , Absorción Intestinal/fisiología , Sirolimus/administración & dosificación , Sirolimus/farmacocinética , Administración Oral , Animales , Antibacterianos/administración & dosificación , Antibacterianos/química , Antibacterianos/farmacocinética , Disponibilidad Biológica , Perros , Emulsiones/administración & dosificación , Emulsiones/química , Emulsiones/farmacocinética , Absorción Intestinal/efectos de los fármacos , Masculino , Dióxido de Silicio/administración & dosificación , Dióxido de Silicio/química , Dióxido de Silicio/farmacocinética , Sirolimus/química , Solubilidad , Propiedades de Superficie
4.
Nat Commun ; 12(1): 1431, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33664266

RESUMEN

The structural complexity and bioactivity of natural products often depend on enzymatic redox tailoring steps. This is exemplified by the generation of the bisbenzannulated [5,6]-spiroketal pharmacophore in the bacterial rubromycin family of aromatic polyketides, which exhibit a wide array of bioactivities such as the inhibition of HIV reverse transcriptase or DNA helicase. Here we elucidate the complex flavoenzyme-driven formation of the rubromycin pharmacophore that is markedly distinct from conventional (bio)synthetic strategies for spiroketal formation. Accordingly, a polycyclic aromatic precursor undergoes extensive enzymatic oxidative rearrangement catalyzed by two flavoprotein monooxygenases and a flavoprotein oxidase that ultimately results in a drastic distortion of the carbon skeleton. The one-pot in vitro reconstitution of the key enzymatic steps as well as the comprehensive characterization of reactive intermediates allow to unravel the intricate underlying reactions, during which four carbon-carbon bonds are broken and two CO2 become eliminated. This work provides detailed insight into perplexing redox tailoring enzymology that sets the stage for the (chemo)enzymatic production and bioengineering of bioactive spiroketal-containing polyketides.


Asunto(s)
Antibacterianos/síntesis química , Furanos/síntesis química , Oxigenasas de Función Mixta/metabolismo , Policétidos/química , Compuestos de Espiro/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Productos Biológicos/farmacología , ADN Helicasas/antagonistas & inhibidores , Furanos/farmacología , Transcriptasa Inversa del VIH/antagonistas & inhibidores , Oxidación-Reducción , Policétidos/farmacología , Compuestos de Espiro/farmacología
5.
Nat Commun ; 12(1): 1732, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33741980

RESUMEN

Macrolides are a class of antibiotics widely used in both medicine and agriculture. Unsurprisingly, as a consequence of their exensive usage a plethora of resistance mechanisms have been encountered in pathogenic bacteria. One of these resistance mechanisms entails the enzymatic cleavage of the macrolides' macrolactone ring by erythromycin esterases (Eres). The most frequently identified Ere enzyme is EreA, which confers resistance to the majority of clinically used macrolides. Despite the role Eres play in macrolide resistance, research into this family enzymes has been sparse. Here, we report the first three-dimensional structures of an erythromycin esterase, EreC. EreC is an extremely close homologue of EreA, displaying more than 90% sequence identity. Two structures of this enzyme, in conjunction with in silico flexible docking studies and previously reported mutagenesis data allowed for the proposal of a detailed catalytic mechanism for the Ere family of enzymes, labeling them as metal-independent hydrolases. Also presented are substrate spectrum assays for different members of the Ere family. The results from these assays together with an examination of residue conservation for the macrolide binding site in Eres, suggests two distinct active site archetypes within the Ere enzyme family.


Asunto(s)
Antibacterianos/química , Farmacorresistencia Bacteriana/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Esterasas/química , Esterasas/genética , Macrólidos/química , Antibacterianos/farmacología , Bacterias/enzimología , Bacterias/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Eritromicina/química , Genes Bacterianos , Macrólidos/farmacología , Simulación del Acoplamiento Molecular , Conformación Proteica , Difracción de Rayos X
6.
Arch Insect Biochem Physiol ; 106(3): e21771, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33644898

RESUMEN

Antimicrobial proteins (AMPs) are small, cationic proteins that exhibit activity against bacteria, viruses, parasites, fungi as well as boost host-specific innate immune responses. Insects produce these AMPs in the fat body and hemocytes, and release them into the hemolymph upon microbial infection. Hemolymph was collected from the bacterially immunized fifth instar larvae of tasar silkworm, Antheraea mylitta, and an AMP was purified by organic solvent extraction followed by size exclusion and reverse-phase high-pressure liquid chromatography. The purity of AMP was confirmed by thin-layer chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The molecular mass was determined by matrix-assisted laser desorption ionization-time of flight mass spectrometry as 14 kDa, and hence designated as AmAMP14. Peptide mass fingerprinting of trypsin-digested AmAMP14 followed by de novo sequencing of one peptide fragment by tandem mass spectrometry analysis revealed the amino acid sequences as CTSPKQCLPPCK. No homology was found in the database search and indicates it as a novel AMP. The minimum inhibitory concentration of the purified AmAMP14 was determined against Escherichia coli, Staphylococcus aureus, and Candida albicans as 30, 60, and 30 µg/ml, respectively. Electron microscopic examination of the AmAMP14-treated cells revealed membrane damage and release of cytoplasmic contents. All these results suggest the production of a novel 14 kDa AMP in the hemolymph of A. mylitta to provide defense against microbial infection.


Asunto(s)
Péptidos Catiónicos Antimicrobianos , Hemolinfa/metabolismo , Proteínas de Insectos/aislamiento & purificación , Mariposas Nocturnas/metabolismo , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/farmacología , Candida albicans/efectos de los fármacos , Cromatografía en Gel/métodos , Cromatografía Líquida de Alta Presión/métodos , Escherichia coli/efectos de los fármacos , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Proteínas de Insectos/farmacología , Larva/metabolismo , Extracción Líquido-Líquido/métodos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos
7.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652616

RESUMEN

The main aims of the research were to produce efficient nanofibrous filters with long-term antibacterial properties and to confirm the functionality of samples under real filtration conditions. A polyurethane solution was modified by micro- or nanoparticles of copper oxide in order to juxtapose the aggregation tendency of particles depending on their size. Modified solutions were electrospun by the Nanospider technique. The roller spinning electrode with a needle surface and static wire electrode were used for the production of functionalized nanofibers. The antibacterial properties of the modified nanofibrous layers were studied under simulated conditions of water and air filtration. Particular attention was paid to the fixation mechanism of modifiers in the structure of filters. It was determined that the rotating electrode with the needle surface is more efficient for the spinning of composite solutions due to the continuous mixing and the avoidance of particle precipitation at the bottom of the bath with modified polyurethane. Moreover, it was possible to state that microparticles of copper oxide are more appropriate antimicrobial additives due to their weaker aggregation tendency but stronger fixation in the fibrous structure than nanoparticles. From the results, it is possible to conclude that nanofibers with well-studied durable antibacterial properties may be recommended as excellent materials for water and air filtration applications.


Asunto(s)
Antibacterianos/química , Infecciones Bacterianas/tratamiento farmacológico , Nanofibras/química , Nanopartículas/química , Antibacterianos/farmacología , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/patología , Cobre/química , Humanos , Membranas Artificiales , Poliuretanos/química
8.
Carbohydr Polym ; 260: 117806, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712152

RESUMEN

Chitin-encapsulated cadmium sulfide quantum dots (CdS@CTN QDs) were successfully synthesized from chitin and Cd(NO3)2 precursor using the colloidal chemistry method, toward the development of biocompatible and biodegradable QDs for biomedical applications. CdS@CTN QDs exhibited the nanocrystalline cubic CdS encapsulated by α-chitin. The average particle size of CdS@CTN QDs was estimated using empirical Henglein model to be 3.9 nm, while their crystallite size was predicted using Scherrer equation to be 4.3 nm, slightly larger compared to 3-mercaptopropionic acid-capped CdS QDs (3.2 and 3.6 nm, respectively). The mechanism of formation was interpreted based on the spectroscopic data and X-ray crystal structures of CdS@CTN QDs fabricated at different pH values and mass ratios of chitin to Cd(NO3)2 precursor. As an important step to explore potential biomolecular and biological applications of CdS@CTN QDs, their antibacterial activities were tested against four different bacterial strains; i.e. Escherichia coli, Bacillus subtillus, Staphylococcus aureus and Pseudomonas aeruginosa.


Asunto(s)
Antibacterianos/química , Materiales Biocompatibles/química , Quitina/química , Puntos Cuánticos/química , Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Compuestos de Cadmio/química , Escherichia coli/efectos de los fármacos , Tamaño de la Partícula , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Sulfuros/química
9.
Carbohydr Polym ; 260: 117835, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712172

RESUMEN

Bacterial breeding is the main cause of food perishability, which is harmful to human health. Silver nanoparticles (AgNPs) are one of the most widely used antimicrobial agents, but they are easy to release and cause cumulative toxicity. In this work, with corn stalk as green reductant and GO as template, a simple electrostatic self-assembled sandwich-like chitosan (CS) wrapped rGO@AgNPs nanocomposite film (CS/rGO@AgNPs) was synthesized to achieve stabilizing and controlled-release of AgNPs. The results showed that the the CS/rGO@AgNPs film continued releasing AgNPs for up to 14 days, and the final release amount of silver nanoparticles was only about 1.9 %. More importantly, the nanocomposite film showed durable antibacterial effect and good antibacterial activity against E. coli and S. aureus, and they showed no toxicity to cells. Hence, the nanocomposite film has potential application as an effective and safe packaging material to prolong the shelf life of food products.


Asunto(s)
Antibacterianos/química , Quitosano/química , Grafito/química , Nanopartículas del Metal/química , Nanocompuestos/química , Antibacterianos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Escherichia coli/efectos de los fármacos , Humanos , Nanocompuestos/toxicidad , Plata/química , Solubilidad , Staphylococcus aureus/efectos de los fármacos , Resistencia a la Tracción
10.
Molecules ; 26(4)2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669637

RESUMEN

Antimicrobial bioassay-guided fractionation of the endophytic fungi Neofusicoccum australe led to the isolation of a new unsymmetrical naphthoquinone dimer, neofusnaphthoquinone B (1), along with four known natural products (2-5). Structure elucidation was conducted by nuclear magnetic resonance (NMR) spectroscopic methods, and the antimicrobial activity of all the natural products was investigated, revealing 1 to be moderately active towards methicillin-resistant Staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 16 µg/mL.


Asunto(s)
Antibacterianos/farmacología , Ascomicetos/química , Endófitos/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antifúngicos/farmacología , Espectroscopía de Resonancia Magnética con Carbono-13 , Muerte Celular/efectos de los fármacos , Dimerización , Escherichia coli/efectos de los fármacos , Células HEK293 , Humanos , Pruebas de Sensibilidad Microbiana , Naftoquinonas/química , Naftoquinonas/farmacología , Espectroscopía de Protones por Resonancia Magnética
11.
Molecules ; 26(4)2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669881

RESUMEN

Ruta chalepensis L. (Rutaceae), a perennial herb with wild and cultivated habitats, is well known for its traditional uses as an anti-inflammatory, analgesic, antipyretic agent, and in the treatment of rheumatism, nerve diseases, neuralgia, dropsy, convulsions and mental disorders. The antimicrobial activities of the crude extracts from the fruits, leaves, stem and roots of R. chalepensis were initially evaluated against two Gram-positive and two Gram-negative bacterial strains and a strain of the fungus Candida albicans. Phytochemical investigation afforded 19 compounds, including alkaloids, coumarins, flavonoid glycosides, a cinnamic acid derivative and a long-chain alkane. These compounds were tested against a panel of methicillin-resistant Staphylococcus aureus (MRSA) strains, i.e., ATCC 25923, SA-1199B, XU212, MRSA-274819 and EMRSA-15. The MIC values of the active compounds, chalepin (9), chalepensin (10), rutamarin (11), rutin 3'-methyl ether (14), rutin 7,4'-dimethyl ether (15), 6-hydroxy-rutin 3',7-dimethyl ether (16) and arborinine (18) were in the range of 32-128 µg/mL against the tested MRSA strains. Compounds 10 and 16 were the most active compounds from R. chalepensis, and were active against four out of six tested MRSA strains, and in silico studies were performed on these compounds. The anti-MRSA activity of compound 16 was comparable to that of the positive control norfloxacin (MICs 32 vs 16 µg/mL, respectively) against the MRSA strain XU212, which is a Kuwaiti hospital isolate that possesses the TetK tetracycline efflux pump. This is the first report on the anti-MRSA property of compounds isolated from R. chalepensis and relevant in silico studies on the most active compounds.


Asunto(s)
Simulación por Computador , Furocumarinas/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ruta/química , Ruta/crecimiento & desarrollo , Rutina/farmacología , Antibacterianos/química , Antibacterianos/farmacología , Furocumarinas/química , Furocumarinas/aislamiento & purificación , Enlace de Hidrógeno , Irak , Ligandos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Rutina/química , Rutina/aislamiento & purificación
12.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670315

RESUMEN

Arabian flora is a rich source of bioactive compounds. In this study, we investigated three aromatic plant species with the aim of finding valuable sources of antimicrobial agents against common pathogenic microorganisms. We focused especially on microorganisms, which cause outbreaks of infectious disease during mass gatherings and pilgrimages season in Saudi Arabia. The essential oils of three aromatic plant species were hydrodistilled from flowering aerial parts of Lavandula pubescens Decne. and Pulicaria incisa subsp. candolleana E.Gamal-Eldin, and from leaves, stems, ripe and unripe fruits of Juniperus procera Hochst. Ex Endl. They were subsequently analyzed by gas chromatography-mass spectrometry (GC-MS). The main constituents of L. pubescens were found to be carvacrol (55.7%), methyl carvacrol (13.4%), and ß-bisabolene (9.1%). P. incisa subsp. Candolleana essential oil was rich in linalool (33.0%), chrysanthenone (10.3%), eugenol (8.9%), and cis-chrysanthenol (8.0%); the major components of J. procera essential oil were α-pinene (31.3-62.5%) and δ-3-carene (7.3-30.3%). These essential oils were tested against thirteen American Type Culture Collection (ATCC) strains of Gram-positive and Gram-negative bacteria using the agar diffusion assay. The only effective essential oil was that of L. pubescens and the most sensitive strains were Acinetobacter baumannii, Salmonella typhimurium, Shigella sonnei, Enterococcus faecalis and Staphylococcus epidermidis. Carvacrol, the major constituent of L. pubescens, was tested on these strains and was compared with vancomycin, amikacin, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays of L. pubescens essential oil and carvacrol revealed that Gram-negative strains were more susceptible than the Gram-positive ones.


Asunto(s)
Juniperus/química , Lavandula/química , Aceites Volátiles/química , Aceites Vegetales/química , Pulicaria/química , Antibacterianos/química , Antibacterianos/farmacología , Cimenos/química , Cimenos/farmacología , Enterococcus faecalis/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/farmacología , Componentes Aéreos de las Plantas/química , Hojas de la Planta/química , Aceites Vegetales/farmacología , Arabia Saudita , Staphylococcus aureus/efectos de los fármacos
13.
Molecules ; 26(4)2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33673039

RESUMEN

Psidium (Myrtaceae) comprises approximately 266 species, distributed in tropical and subtropical regions of the world. Psidium taxa have great ecological, economic, and medicinal relevance due to their essential oils' chemical diversity and biological potential. This review reports 18 Psidium species growing around the world and the chemical and biological properties of their essential oils. Chemically, 110 oil records are reported with significant variability of volatile constituents, according to their seasonality and collection sites. Monoterpenes and sesquiterpenes with acyclic (C10 and C15), p-menthane, pinane, bisabolane, germacrane, caryophyllane, cadinane, and aromadendrane skeleton-types, were the primary constituents. The essential oils showed various biological activities, including antioxidant, antifungal, antibacterial, phytotoxic, larvicidal, anti-inflammatory, and cytotoxic properties. This review contributes to the Psidium species rational and economic exploration as natural sources to produce new drugs.


Asunto(s)
Monoterpenos/química , Aceites Volátiles/química , Psidium/química , Sesquiterpenos/química , Antibacterianos/química , Antibacterianos/uso terapéutico , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Antifúngicos/química , Antifúngicos/uso terapéutico , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Antioxidantes/química , Antioxidantes/uso terapéutico , Humanos , Monoterpenos/uso terapéutico , Aceites Volátiles/uso terapéutico , Aceites Vegetales/química , Sesquiterpenos/uso terapéutico
14.
Food Chem ; 352: 129319, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691215

RESUMEN

Emulsions based on licorice essential oil (LEO) were prepared under different homogenization conditions (ultra-homogenization (U1) or U1 together with sonication (U2)). The obtained emulsions were incorporated into the carboxymethyl cellulose (CMC) film. The results showed that U2 caused significant changes in the size and the surface charge of the emulsions. Remarkable differences in the microstructure were observed between the U1 and the U2 emulsion-based films as revealed by SEM and AFM. Both emulsions reduced the rigidity and increased the flexibility of the films. The film made from the CMC alone had a water vapor permeability (WVP) of 2.66 × 10-9 g m-1 s-1 Pa-1, while the CMC film made from U2 emulsion had a WVP of 1.87 × 10-9 g m-1 s-1 Pa-1. Also, the film containing 0.0125% U1-LEO exhibited antibacterial activity on gram-positive bacteria only while the film containing 0.0125% U2-LEO demonstrated antibacterial activity on both gram-positive and gram-negative bacteria.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Glycyrrhiza/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Sonicación , Carboximetilcelulosa de Sodio/química , Emulsiones , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Permeabilidad , Vapor
15.
Carbohydr Polym ; 260: 117772, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712130

RESUMEN

Nanoparticle-polymer composites are important functional materials but structural control of their assembly is challenging. Owing to its crystalline internal structure and tunable nanoscale morphology, cellulose is promising polymer scaffold for templating such composite materials. Here, we show bottom-up synthesis of reducing end thiol-modified cellulose chains by iterative bi-enzymatic ß-1,4-glycosylation of 1-thio-ß-d-glucose (10 mM), to a degree of polymerization of ∼8 and in a yield of ∼41% on the donor substrate (α-d-glucose 1-phosphate, 100 mM). Synthetic cellulose oligomers self-assemble into highly ordered crystalline (cellulose allomorph II) material showing long (micrometers) and thin nanosheet-like morphologies, with thickness of 5-7 nm. Silver nanoparticles were attached selectively and well dispersed on the surface of the thiol-modified cellulose, in excellent yield (≥ 95%) and high loading efficiency (∼2.2 g silver/g thiol-cellulose). Examined against Escherichia coli and Staphylococcus aureus, surface-patterned nanoparticles show excellent biocidal activity. Bottom-up approach by chemical design to a functional cellulose nanocomposite is presented. Synthetic thiol-containing nanocellulose can expand the scope of top-down produced cellulose materials.


Asunto(s)
Antibacterianos/química , Celulosa/química , Nanopartículas del Metal/química , Nanocompuestos/química , Compuestos de Sulfhidrilo/química , Antibacterianos/farmacología , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/efectos de los fármacos , Nanocompuestos/toxicidad , Plata/química , Staphylococcus aureus/efectos de los fármacos
16.
Molecules ; 26(5)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668096

RESUMEN

Aizoaceae is a large succulent family characterized by many psychoactive species. Aizoon canariense L., a wild neglected plant traditionally used in gastrointestinal ailments, has been the subject of a limited number of phytochemical and biological studies. Therefore, herein, we investigated the in vitro cytotoxic, antimicrobial, and anticholinesteraseactivity of the aerial parts of A. canariense L. and analyzed the phytochemical compositions of the lipoidal and alkaloidal fractions. Petroleum ether extract showed the presence of behenic and tricosylic acid, while an in-depth investigation of the alkaloidal fraction revealed the identification of new adenine based alkaloids (1-5), which were isolated and identified for the first time from Aizoon canariense L. Their structures were elucidated based on extensive spectroscopic analyses. The alkaloidal extract showed a powerful cytotoxic effect (IC50 14-28 µg/mL), with the best effect against colon carcinoma, followed by liver and breast carcinomas. The alkaloidal extract also had a potent effect against Candida albicans and Escherichia coli, with minimum inhibitory concentrations (MIC) values of 312.5 and 625 µg/mL. The in vitro anticholinesterase activity was potent, with IC50 < 200 ng/mL for the tested extracts compared with 27.29 ± 0.49 ng/mL for tacrine.


Asunto(s)
Aizoaceae/química , Alcaloides/farmacología , Antibacterianos/farmacología , Antifúngicos/farmacología , Antineoplásicos Fitogénicos/farmacología , Inhibidores de la Colinesterasa/farmacología , Extractos Vegetales/farmacología , Acetilcolinesterasa/metabolismo , Alcaloides/química , Alcaloides/aislamiento & purificación , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Candida albicans/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Escherichia coli/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Relación Estructura-Actividad
17.
Molecules ; 26(5)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668169

RESUMEN

A series of fifteen silver (I) quinoline complexes Q1-Q15 have been synthesized and studied for their biological activities. Q1-Q15 were synthesized from the reactions of quinolinyl Schiff base derivatives L1-L5 (obtained by condensing 2-quinolinecarboxaldehyde with various aniline derivatives) with AgNO3, AgClO4 and AgCF3SO3. Q1-Q15 were characterized by various spectroscopic techniques and the structures of [Ag(L1)2]NO3Q1, [Ag(L1)2]ClO4Q6, [Ag(L2)2]ClO4Q7, [Ag(L2)2]CF3SO3Q12 and [Ag(L4)2]CF3SO3Q14 were unequivocally determined by single crystal X-ray diffraction analysis. In vitro antimicrobial tests against Gram-positive and Gram-negative bacteria revealed the influence of structure and anion on the complexes' moderate to excellent antibacterial activity. In vitro antioxidant activities of the complexes showed their good radical scavenging activity in ferric reducing antioxidant power (FRAP). Complexes with the fluorine substituent or the thiophene or benzothiazole moieties are more potent with IC50 between 0.95 and 2.22 mg/mL than the standard used, ascorbic acid (2.68 mg/mL). The compounds showed a strong binding affinity with calf thymus-DNA via an intercalation mode and protein through a static quenching mechanism. Cytotoxicity activity was examined against three carcinoma cell lines (HELA, MDA-MB231, and SHSY5Y). [Ag(L2)2]ClO4Q7 with a benzothiazole moiety and [Ag(L4)2]ClO4Q9 with a methyl substituent had excellent cytotoxicity against HELA cells.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Complejos de Coordinación/farmacología , ADN/química , Antibacterianos/síntesis química , Antibacterianos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Antioxidantes/síntesis química , Antioxidantes/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Ensayos de Selección de Medicamentos Antitumorales , Compuestos Férricos/antagonistas & inhibidores , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Quinolinas/química , Quinolinas/farmacología , Bases de Schiff/química , Bases de Schiff/farmacología , Plata/química , Plata/farmacología
18.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672486

RESUMEN

Medicinal plants and their derived compounds have drawn the attention of researchers due to their considerable impact on human health. Among medicinal plants, mint (Mentha species) exhibits multiple health beneficial properties, such as prevention from cancer development and anti-obesity, antimicrobial, anti-inflammatory, anti-diabetic, and cardioprotective effects, as a result of its antioxidant potential, combined with low toxicity and high efficacy. Mentha species are widely used in savory dishes, food, beverages, and confectionary products. Phytochemicals derived from mint also showed anticancer activity against different types of human cancers such as cervix, lung, breast and many others. Mint essential oils show a great cytotoxicity potential, by modulating MAPK and PI3k/Akt pathways; they also induce apoptosis, suppress invasion and migration potential of cancer cells lines along with cell cycle arrest, upregulation of Bax and p53 genes, modulation of TNF, IL-6, IFN-γ, IL-8, and induction of senescence phenotype. Essential oils from mint have also been found to exert antibacterial activities against Bacillus subtilis, Streptococcus aureus, Pseudomonas aeruginosa, and many others. The current review highlights the antimicrobial role of mint-derived compounds and essential oils with a special emphasis on anticancer activities, clinical data and adverse effects displayed by such versatile plants.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Mentha/química , Aceites Volátiles/farmacología , Fitoquímicos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Bacterias/efectos de los fármacos , Compuestos de Bifenilo/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Humanos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Picratos/antagonistas & inhibidores
19.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672630

RESUMEN

Despite advances achieved over the last decade, infections caused by multi-drug-resistant bacterial strains are increasingly becoming important societal issues that need to be addressed. New approaches have already been developed in order to overcome this problem. Photodynamic antimicrobial chemotherapy (PACT) could provide an alternative to fight infectious bacteria. Many studies have highlighted the value of cationic photosensitizers in order to improve this approach. This study reports the synthesis and the characterization of cationic porphyrins derived from methylimidazolium and phenylimidazolium porphyrins, along with a comparison of their photophysical properties with the well-known N-methylpyridyl (pyridinium) porphyrin family. PACT tests conducted with the tetracationic porphyrins of these three families showed that these new photosensitizers may offer a good alternative to the classical pyridinium porphyrins, especially against S.aureus and E.coli. In addition, they pave the way to new cationic photosensitizers by the means of derivatization through amide bond formation.


Asunto(s)
Antibacterianos/farmacología , Imidazoles/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Porfirinas/farmacología , Piridinas/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Imidazoles/síntesis química , Imidazoles/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/química , Porfirinas/síntesis química , Porfirinas/química , Pseudomonas aeruginosa/efectos de los fármacos , Piridinas/síntesis química , Piridinas/química , Staphylococcus aureus/efectos de los fármacos
20.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672753

RESUMEN

The cell wall of Mycobacterium tuberculosis (Mtb) has a unique structural organisation, comprising a high lipid content mixed with polysaccharides. This makes cell wall a formidable barrier impermeable to hydrophilic agents. In addition, during host infection, Mtb resides in macrophages within avascular necrotic granulomas and cavities, which shield the bacterium from the action of most antibiotics. To overcome these protective barriers, a new class of anti-TB agents exhibiting lipophilic character have been recommended by various reports in literature. Herein, a series of lipophilic heterocyclic quinolone compounds was synthesised and evaluated in vitro against pMSp12::GFP strain of Mtb, two protozoan parasites (Plasmodium falciparum and Trypanosoma brucei brucei) and against ESKAPE pathogens. The resultant compounds exhibited varied anti-Mtb activity with MIC90 values in the range of 0.24-31 µM. Cross-screening against P. falciparum and T.b. brucei, identified several compounds with antiprotozoal activities in the range of 0.4-20 µM. Compounds were generally inactive against ESKAPE pathogens, with only compounds 8c, 8g and 13 exhibiting moderate to poor activity against S. aureus and A. baumannii.


Asunto(s)
Antibacterianos/farmacología , Antiprotozoarios/farmacología , Quinolonas/farmacología , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Plasmodium falciparum/efectos de los fármacos , Quinolonas/síntesis química , Quinolonas/química , Staphylococcus aureus/efectos de los fármacos , Trypanosoma brucei brucei/efectos de los fármacos
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