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1.
Phys Chem Chem Phys ; 21(37): 20750-20756, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31513191

RESUMO

"Intelligent" materials based on synthetic small molecules that become functional only under specific conditions provide new opportunities for developing regulated systems aimed at a large number of applications. For instance, biologically active supramolecular entities that are sensitive to environmental conditions, such as the presence of bacterial membranes, are extremely interesting in biomedicine. In this work, we have designed and investigated, using molecular dynamics simulations, a doubly modulable nanotube formed by the self-assembly of cyclic peptides sensitive to both the presence of a lipid membrane and the pH of the aqueous media. The cyclic peptides were designed to self-assemble into peptide nanotubes in the presence of a lipid bilayer and at low pH values. Under these conditions, the residual side chains point outside the cyclic peptides, being exposed to the lipid bilayer, and the inner groups (carboxylic acids) are protonated, thus allowing the permeation of water and preventing that of ions. Higher pH values are expected to create carboxylate groups at the lumen of the peptides, leading to the disassembly of the nanotube, the attraction and translocation of ions towards the hydrophobic core of the bilayer, and eventually killing the target malignant cells. Our results suggest that by introducing a second switch in a membrane sensitive system, it is possible to modulate its interaction with the lipid bilayer. This opens the door to new strategies for the preparation of antimicrobial peptides that interact at the membrane level.


Assuntos
Nanotubos de Peptídeos/química , Peptídeos Cíclicos/química , Anti-Infecciosos/química , Bactérias/química , Concentração de Íons de Hidrogênio , Bicamadas Lipídicas/química , Simulação de Dinâmica Molecular
2.
Pestic Biochem Physiol ; 158: 185-200, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378356

RESUMO

The present work describes the antimicrobial action of 25 monoterpenes (six hydrocarbons, five ketones, two aldehydes, six alcohols and six acetate analogues) against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus and antifungal activity against Aspergillus flavus. The antibacterial activity was evaluated by broth microdilution technique as a minimum inhibitory concentration (MIC) and the antifungal activity was performed by mycelia radial growth technique as the effective concentration causing 50% inhibition of the mycelial growth (EC50). The results showed that thymol and α-terpineol were the most potent against E. coli (MIC = 45 and 55 mg/L, respectively) and S. aureus (MIC = 135 and 225 mg/L, respectively). The results also showed that thymol displayed the maximum antifungal action against A. flavus with EC50 20 mg/L. Furthermore, the antioxidant activity was determined using N,N-dimethyl-1,4-phenylenediamine (DMPD) and the results showed that geraniol were the most potent compound (IC50 = 19 mg/L). Molecular docking studies indicated that the compounds displayed different binding interactions with the amino acid residues at the catalytic sites of N5-carboxyaminoimidazole synthetase and oxysterol binding protein Osh4 enzymes. Non-covalent interactions including van der Waals, hydrogen bonding as well as hydrophobic were observed between the compounds and the enzymes. A significant relationship was found between the docking score and the biological activity of the tested monoterpenes compared to the ceftriaxone and carbendazim as standard bactericide and fungicide, respectively. In silico ADMET properties were also performed and displayed potential for the development of promising antimicrobial agents. For these reasons, these compounds may be considered as potential ecofriendly alternatives in food preservation to delay or prevent the microbial infection and prolong the shelf life of food products.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Monoterpenos/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Cicloexenos/química , Cicloexenos/farmacologia , Escherichia coli/efeitos dos fármacos , Hidrocarbonetos/química , Hidrocarbonetos/farmacologia , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos
3.
Food Chem ; 298: 125079, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260959

RESUMO

Citral-in-water emulsions were prepared with two different essential oil concentrations of 2.5 and 5.0% (w/w), then spray-dried in the presence of the same amount of maltodextrins (20%). The microcapsules were prepared with two different emulsifier compositions: monolayer microcapsules (ML) stabilized by sodium caseinate alone and layer-by-layer microcapsules (LBL) stabilized by sodium caseinate and pectin. The encapsulation efficiency was higher for LBL microcapsules (e.g. 99.6 ±â€¯0.4% for 2.5% citral) than that for ML ones (e.g. 78.6 ±â€¯0.6% for 2.5% citral) which confirm that the additional pectin layer was able to protect citral during the spray-drying process whatever citral concentration. Furthermore, our results showed that the antibacterial activity of the obtained microcapsules significantly depends on both citral concentration and interfacial membrane composition. The presence of two layers surrounding the citral droplets may result in a progressive and controlled release of the encapsulated citral.


Assuntos
Emulsões/química , Monoterpenos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cápsulas/química , Caseínas/química , Dessecação , Listeria/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Tamanho da Partícula , Pectinas/química , Polissacarídeos/química , Staphylococcus aureus/efeitos dos fármacos
4.
J Microbiol Biotechnol ; 29(7): 1009-1013, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31288302

RESUMO

Polymeric nanoparticles are widely used for drug delivery due to their biodegradability property. Among the wide array of polymers, chitosan has received growing interest among researchers. It was widely used as a vehicle in polymeric nanoparticles for drug targeting. This review explored the current research on the antimicrobial activity of chitosan nanoparticles (ChNP) and the impact on the clinical applications. The antimicrobial activities of ChNP were widely reported against bacteria, fungi, yeasts and algae, in both in vivo and in vitro studies. For pharmaceutical applications, ChNP were used as antimicrobial coating for promoting wound healing, preventing infections and combating the rise of infectious disease. Besides, ChNP also exhibited significant inhibitory on foodborne microorganisms, particularly on fruits and vegetables. It is noteworthy that ChNP can be also applied to deliver antimicrobial drugs, which further enhance the efficiency and stability of the antimicrobial agent. The present review addresses the potential antimicrobial applications of ChNP from these few aspects.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Quitosana/química , Portadores de Fármacos/química , Fungos/efeitos dos fármacos , Nanopartículas/química , Materiais Biocompatíveis , Sistemas de Liberação de Medicamentos , Humanos , Nanotecnologia , Polímeros/química
5.
Chem Pharm Bull (Tokyo) ; 67(7): 620-631, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257316

RESUMO

Natural products are still rich sources of clinically used medicines and lead compounds for them. This review summarizes chemical studies carried out by the author on natural products of microorganism origin, many of which were discovered at the Institute of Microbial Chemistry (BIKAKEN). Caprazamycin B is a liponucleoside antibiotic from which CPZEN-45, an antituberculosis agent with a unique mode of action, was developed. Intervenolin and leucinostatin A exert antiproliferative activity toward tumor cells in the presence of the corresponding stromal cells, which implies that the primary molecular targets of these molecules should be related to growth signals from normal (stromal) cells. Details of the endeavors to establish efficient synthetic routes to these compounds which accelerated structure-activity relationship studies and further evaluation of biological activity are described.


Assuntos
Anti-Infecciosos/química , Antineoplásicos/química , Produtos Biológicos/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Azepinas/química , Azepinas/farmacologia , Produtos Biológicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Peptídeos/química , Peptídeos/farmacologia , Relação Estrutura-Atividade
6.
Naturwissenschaften ; 106(7-8): 37, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31209578

RESUMO

Millipedes use an array of chemical compounds to defend themselves from predator attack. These chemical substances can have additional roles, i.e. defence against various pathogens. We evaluated the efficacy of the defensive secretion of Apfelbeckia insculpta (L. Koch, 1867) against bacteria, yeasts, and filamentous fungi. The tested secretion consisted of two compounds, p-cresol and phenol, and showed antibacterial, antibiofilm, and antifungal potential against all selected microorganisms. The most sensitive bacterium in our study was Pseudomonas aeruginosa, while the tested defensive secretion manifested the lowest activity against Escherichia coli. The defensive secretion of A. insculpta also showed an ability, albeit mild, to suppress biofilm formation by P. aeruginosa. Among the tested yeasts, Candida albicans and C. krusei were the most susceptible and most resistant species, respectively. Finally, the concentration of extracts obtained from the tested defensive secretion needed to achieve an antifungal effect was lowest in the case of Cladosporium cladosporioides. Fusarium verticillioides and Penicillium rubens were the micromycetes most resistant to the tested secretion. Our results indicate that antibacterial activity of the defensive secretion of A. insculpta is similar to or slightly weaker than that of streptomycin, while comparison with antimycotics showed that the tested millipede secretion has stronger activity than fluconazole, but weaker activity than nystatin and ketoconazole. The present study corroborates previous findings indicating that the defensive secretions of millipedes can have different roles apart from antipredator protection and are effective against pathogenic microorganisms.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Artrópodes/química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Fenóis/química , Animais , Anti-Infecciosos/isolamento & purificação , Península Balcânica , Testes de Sensibilidade Microbiana
7.
BMC Complement Altern Med ; 19(1): 146, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227024

RESUMO

BACKGROUND: There is increasing interest in the pharmaceutical and food industries to substitute synthetic chemicals with naturally occurring compounds possessing bioactive properties. Plants are valuable sources of bioactive compounds. The present study investigates the chemical composition and antioxidant, antimicrobial, and anticancer activities of ethanolic extracts (EEs) and essential oils (EOs) from two species in the Lamiaceae family, Ocimum basilicum L. and Thymus algeriensis Boiss. & Reut., cultivated in the Algerian Saharan Atlas. METHODS: The total flavonoid contents of the plants' ethanolic extracts were determined by the aluminium chloride method, while the total phenols were determined using the Folin-Ciocalteu method. Essential oils were obtained by hydrodistillation of the aerial parts of the plants and were analysed by GC-MS. The free radical-scavenging ability and antioxidant potential of the plants' EEs and EOs were probed using the 2, 2-diphenyl-picrylhydrazyl radical-scavenging, ABTS radical-scavenging, ferric-reducing power and phosphomolybdenum assays. The antimicrobial activities were evaluated against several pathogens characteristic of gram-negative bacteria (three species), gram-positive bacteria (three species) and fungi (two species). The microdilution method was used to estimate the minimum inhibitory concentrations (MICs). The oils' anticancer potential against several cancer types was also studied using the MTT assay and reported as the toxic doses that resulted in a 50% reduction in cancer cell growth (LD50). RESULTS: Phenolic compounds in the EEs from both plants were analysed by HPLC and demonstrated a rich flavonoid content. Chemical analysis of the essential oil from Ocimum basilicum revealed 26 unique compounds, with linalool (52.1%) and linalyl acetate (19.1%) as the major compounds. A total of 29 compounds were identified in the essential oil from Thymus algeriensis, with α-terpinyl acetate (47.4%), neryl acetate (9.6%), and α-pinene (6.8%) as the major compounds. The ethanolic extracts and essential oils from both plants exhibited moderate antioxidant activities and moderate to weak antimicrobial activities. Furthermore, anticancer activities against the examined human cancer cell lines were associated with only the EOs from both plants, with LD50 values ranging between 300 and 1000 µg/mL. CONCLUSION: The results suggest that the bioactive compounds found in the ethanolic extracts and essential oils from Ocimum basilicum and Thymus algeriensis, with diverse antioxidant, antimicrobial and anticancer activities, may have beneficial applications in nutraceutical and pharmaceutical technologies.


Assuntos
Ocimum basilicum/química , Óleos Voláteis/química , Óleos Vegetais/química , Thymus (Planta)/química , Argélia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Linhagem Celular Tumoral , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Fenol/química , Fenol/farmacologia , Óleos Vegetais/farmacologia
8.
Int J Nanomedicine ; 14: 3583-3600, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190813

RESUMO

Purpose: This study aimed to decorate the surface of TiO2 nanotubes (TiO2 NTs) grown on medical grade Ti-6Al-4V alloy with an antimicrobial layer of nano zinc oxide particles (nZnO) and then determine if the antimicrobial properties were maintained with a final layer of nano-hydroxyapatite (HA) on the composite. Methods: The additions of nZnO were attempted at three different annealing temperatures: 350, 450 and 550 °C. Of these temperatures, 350°C provided the most uniform and nanoporous coating and was selected for antimicrobial testing. Results: The LIVE/DEAD assay showed that ZnCl2 and nZnO alone were >90% biocidal to the attached bacteria, and nZnO as a coating on the nanotubes resulted in around 70% biocidal activity. The lactate production assay agreed with the LIVE/DEAD assay. The concentrations of lactate produced by the attached bacteria on the surface of nZnO-coated TiO2 NTs and ZnO/HA-coated TiO2 NTs were 0.13±0.03 mM and 0.37±0.1 mM, respectively, which was significantly lower than that produced by the bacteria on TiO2 NTs alone, 1.09±0.30 mM (Kruskal-Wallis, P<0.05, n=6). These biochemical measurements were correlated with electron micrographs of cell morphology and cell coverage on the coatings. Conclusion: nZnO on TiO2 NTs was a stable and antimicrobial coating, and most of the biocidal properties remained in the presence of nano-HA on the coating.


Assuntos
Anti-Infecciosos/farmacologia , Materiais Revestidos Biocompatíveis/química , Durapatita/química , Nanotubos/química , Staphylococcus aureus/efeitos dos fármacos , Titânio/química , Óxido de Zinco/química , Zinco/farmacologia , Anti-Infecciosos/química , Preparações de Ação Retardada/química , Diálise , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanotubos/ultraestrutura , Propriedades de Superfície
9.
J Photochem Photobiol B ; 197: 111529, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31220803

RESUMO

The therapeutic molecules recovered from the marine biological origin are widely used for the treatment of diverse levels of infections caused by microbial pathogens. In addition, the eco-friendly preparations of nanomaterials together with the secondary metabolites' producing active microbial strains effectively suppress the spreading of the pathogenic bacteria. Considering their importance, the present study evaluated the environmental friendly synthesis of Silver nitrate nanomaterials (SNM) from the active marine Streptomyces strain Al-Dhabi-91 isolated from the Dammam region of Saudi Arabia. The obtained SNM was chemically characterized by various spectroscopic techniques such as UV, XRD, FTIR, SEM, TEM and EDAX; and its biological applications such as antimicrobial properties and antioxidant potential were recorded by DPPH methods. Biochemical and micromorphological studies together with the molecular techniques confirmed that the isolate Al-Dhabi-91 belonged to Streptomyces species. The characterization techniques confirmed that the UV spectrum showed maximum absorption peak at 305 nm indicating the plasmodium characteristics. SEM and TEM analyses evidenced 5-2 nm which are agglomerated, cool to form porous asymmetrical networks. Additionally, the FTIR spectrum showed maximum peak at 1194 cm-1 and 1394 cm-1, confirming the presence of aromatic CH bending and aromatic CC bending in the SNM. SNM exhibited prolific antibacterial activity against Gram negative pathogens, K. pneumoniae (28.33 mm) and E. coli (21.66 mm) respectively. The MIC values of SNM were significant with respect to E. faecalis (125 µg/ml), S. aureus (250 µg/ml), P. aeruginosa (125 µg/ml), K. pneumoniae (500 µg/ml) and E. coli (250 µg/ml) respectively. In addition, the antioxidant potential of the SNM was another value added importance. Especially 50 µg/ml of the nanoparticles showed 33% antioxidant potential; similarly in nitric oxide radical inhibition assay the concentration of 50 µg/ml nanoparticles showed 33% of inhibition potential. Overall, the eco-friendly synthesis of SNM from the marine Streptomyces strain Al-Dhabi-91 was an ideal active source for the treatment of infectious disease and health associated disorders.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Sedimentos Geológicos/microbiologia , Nanopartículas Metálicas/química , Prata/química , Streptomyces/química , Anti-Infecciosos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Filogenia , Arábia Saudita , Streptomyces/classificação , Streptomyces/isolamento & purificação
10.
J Photochem Photobiol B ; 197: 111528, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31226526

RESUMO

Root conditioners are used to promote root surface biomodification to increase the success rate of root coverage. Citric acid and tetracycline are commonly used. There is recent indication for using antimicrobial photodynamic therapy (aPDT) with this purpose. The aim of this study is to evaluate the effects of citric acid/tetracycline gel and aPDT in root coverage of gingival recessions using subepithelial connective tissue graft. This parallel, double-blinded clinical trial enrolled 17 patients (60 recession defects; 20/group). Experimental groups were: Control group (SRP) - scaling and root planing only; Citric acid/tetracycline gel (CAT) group - SRP plus citric acid/tetracycline gel; aPDT - SRP, toluidine blue O (100 µl/ml) and red laser. At baseline and after 3, 6 and 12 months, the clinical parameters were evaluated: recession depth (RD), percentage of root coverage (%RC), keratinized tissue width (KTW), soft tissue thickness (STT), probing depth (PD), clinical attachment level (CAL), dentin hypersensitivity (HYPER) and esthetic perception by patient (EST). CAT group presented reduction in PD, CAL, RD, increase in KTW and STT, higher %RC (81.6%) and better esthetic in relation to SRP group (p < .05). aPDT treatment promoted CAL reduction, gain of KTW and STT and higher %RC (82.1%) in relation to SRP (57.7%) (p < .05). There was a reduction in dentin sensitivity in all groups. Complete root coverage was higher for CAT group (65%) and aPDT group (70%) in relation to SRP (30%) (p < .05). Root conditioning, with citric acid/tetracycline gel and aPDT, promotes better long-term clinical outcomes and root coverage after SCTG procedures.


Assuntos
Ácido Cítrico/química , Gengiva/transplante , Retração Gengival/terapia , Lasers , Tetraciclina/química , Adulto , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Sensibilidade da Dentina/patologia , Método Duplo-Cego , Feminino , Géis/química , Gengiva/patologia , Retração Gengival/patologia , Regeneração Tecidual Guiada Periodontal , Humanos , Masculino , Pessoa de Meia-Idade , Fotoquimioterapia , Aplainamento Radicular , Tetraciclina/uso terapêutico , Raiz Dentária/cirurgia , Resultado do Tratamento , Adulto Jovem
11.
Chem Biol Interact ; 308: 294-303, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158333

RESUMO

The emergence of multidrug resistant (MDR) pathogens is a global threat and has created problems in providing adequate treatment of many infectious diseases. Although the conventional antimicrobial agents are quite effective against several pathogens, yet there is a need for more effective antimicrobial agents against MDR pathogens. Herbal drugs and phytochemicals have been used for their effective antimicrobial activity from ancient times and there is an increasing trend for development of plant based natural products for the prevention and treatment of pathogenic diseases. One of the strategies for effective resistance modification is the use of antimicrobial agent-phytochemical combinations that will neutralize the resistance mechanism, enabling the drug to still be effective against resistant microbes. These phytochemicals can work by several strategies, such as inhibition of target modifying and drug degrading enzymes or as efflux pumps inhibitors. A plethora of herbal extracts, essential oils and isolated pure compounds have been reported to act synergistically with existing antibiotics, antifungals and chemotherapeutics and augment the activity of these drugs. Considerable increases in the susceptibility pattern of several microbes towards the natural antimicrobials and their combinations were observed as indicated by significant decline in minimum inhibitory concentrations. This review paper summarizes the current developments regarding synergistic interactions of plant extracts and isolated pure compounds in combination with existing antibacterial, antifungal agents and chemotherapeutics. The effect of these agents on the susceptibility patterns of these pathogens and possible mechanisms of action are described in detail. In conclusion, many phytochemicals in combination with existing drugs were found to act as resistance modifying agents and proper combinations may rescue the efficacy of important lifesaving antimicrobial agents.


Assuntos
Anti-Infecciosos/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Antivirais/química , Antivirais/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Vírus de DNA/efeitos dos fármacos , Sinergismo Farmacológico , Fungos/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , beta-Lactamases/química , beta-Lactamases/metabolismo
12.
Food Chem ; 295: 588-598, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174800

RESUMO

The encapsulation of eugenol (E) by spray-drying using whey protein (WP) or soy lecithin (LE) and maltodextrin in combination with oleic acid (OA) and chitosan (CH) was analysed in order to obtain antioxidant and antimicrobial powders for food applications. Formulations with only WP or LE showed higher encapsulation efficiencies (EE) (95-98%) and antibacterial effect against E. coli and L. innocua due to their greater E load. Incorporation of OA or CH promoted lower EE, which negatively affected the antimicrobial and antioxidant activities of the powders. Furthermore, the addition of CH implied less thermal protection against the E losses. The eugenol release was not notably affected by pH or polarity of the food simulant, but the release rate significantly decreased when incorporating OA and CH. The E-LE formulations better retained the eugenol than E-WP powders when heated above 200 °C, this being relevant for the powder inclusion in thermally treated products.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Dessecação/métodos , Eugenol/química , Lecitinas/química , Proteínas do Soro do Leite/química , Anti-Infecciosos/farmacologia , Quitosana/química , Composição de Medicamentos , Escherichia coli/efeitos dos fármacos , Cinética , Listeria/efeitos dos fármacos , Ácido Oleico/química , Polissacarídeos/química
13.
Food Chem ; 295: 671-679, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174811

RESUMO

The aim of this work was to develop and optimize a pH-responsive nanoparticle based on poly(D,L-lactide-co-glycolide) (PLGA) and chitosan (CHIT) for delivery of natural antimicrobial using trans-cinnamaldehyde (TCIN) as a model compound. The optimization was performed using a central composite design and the desirability function approach. The optimized levels of variables considering all significant responses were 4% (w/w) of TCIN and 6.75% (w/w) of CHIT. After, optimized nanoparticles were produced and characterized according to their physicochemical properties and their antimicrobial activity against Salmonella Typhimurium and Staphylococcus aureus. Optimized nanoparticles characterization indicated a satisfactory TCIN encapsulation (33.20 ±â€¯0.85%), spherical shape, pH-responsive controlled release, with faster release in the presence of CHIT at low pH, and enhanced antimicrobial activity against both pathogens. TCIN encapsulation using PLGA coated with CHIT enhanced its antimicrobial activity and generated a delivery system with pH-sensitivity for controlled release with promising properties for food safety applications.


Assuntos
Anti-Infecciosos/química , Quitosana/sangue , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Acroleína/análogos & derivados , Acroleína/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Varredura Diferencial de Calorimetria , Quitosana/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Salmonella/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
14.
Ann Agric Environ Med ; 26(2): 290-297, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31232061

RESUMO

INTRODUCTION AND OBJECTIVE: Since antiquity, C. babylonica (L.) L. extracts has been used as a remedy for primary health care in traditional medicine. In this study, a total of seven different crude extracts (acetone, chloroform, hexane, ethylacetate, methanol, ethanol and water) from branches and leaves of C. babylonica (L.) L. were prepared to determine antimicrobial and antiproliferative activity against cancer cell lines. MATERIAL AND METHODS: MIC assay was used for antimicrobial activity against gram positive and gram negative bacteria, and one yeast. MTT assay was applied to screen the antiproliferative activity of seven extracts, and to determine dose- and time-dependent effects of the aceton extract on A549, PC-3, MCF-7, and HeLa cell lines. RESULTS: The aceton extract of C.babylonica (L.) L. showed the best antibacterial activity against Bacillus cereus, P. aeruginosa and C. albicans (MIC: 1.6 mg/mL). GC-MS analyses allowed six compounds to be determined; the main constituents of acetone extract from C. babylonica (L.) L. were diacetone alcohol (53.47 %), 1-dexadecene (10.19 %) and 1-tetradecene (8.67 %). In addition, seven different solvent extracts at 500 µg/mL caused antiproliferative activity between 84% - 88%, compared to control. Dose-dependent effects of the extracts on A549 cells indicated that chloroform, ethyl acetate, and aceton extract were the most effective extracts with the IC50 values of 9, 33, and 36 µg/mL, respectively. CONCLUSIONS: The results clearly demonstrate that C. babylonica (L.) L. exhibited a strong antimicrobial effect and antiproliferative activity against cancer cells in vitro. Further studies are required to isolate and characterize the active pure compounds responsible for the antimicrobial and antiproliferative activities.


Assuntos
Anti-Infecciosos/farmacologia , Proliferação de Células/efeitos dos fármacos , Centaurea/química , Inibidores do Crescimento/farmacologia , Extratos Vegetais/farmacologia , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Inibidores do Crescimento/química , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Leveduras/efeitos dos fármacos
15.
Cell Mol Life Sci ; 76(18): 3667-3678, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062071

RESUMO

Cardiolipins (CLs) are tetra-acylated diphosphatidylglycerols found in bacteria, yeast, plants, and animals. In healthy mammals, CLs are unsaturated, whereas saturated CLs are found in blood cells from Barth syndrome patients and in some Gram-positive bacteria. Here, we show that unsaturated but not saturated CLs block LPS-induced NF-κB activation, TNF-α and IP-10 secretion in human and murine macrophages, as well as LPS-induced TNF-α and IL-1ß release in human blood mononuclear cells. Using HEK293 cells transfected with Toll-like receptor 4 (TLR4) and its co-receptor Myeloid Differentiation 2 (MD2), we demonstrate that unsaturated CLs compete with LPS for binding TLR4/MD2 preventing its activation, whereas saturated CLs are TLR4/MD2 agonists. As a consequence, saturated CLs induce a pro-inflammatory response in macrophages characterized by TNF-α and IP-10 secretion, and activate the alternative NLRP3 inflammasome pathway in human blood-derived monocytes. Thus, we identify that double bonds discriminate between anti- and pro-inflammatory properties of tetra-acylated molecules, providing a rationale for the development of TLR4 activators and inhibitors for use as vaccine adjuvants or in the treatment of TLR4-related diseases.


Assuntos
Cardiolipinas/farmacologia , Macrófagos/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Ligação Competitiva , Cardiolipinas/química , Cardiolipinas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Quimiocina CXCL10/metabolismo , Células HEK293 , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Antígeno 96 de Linfócito/genética , Antígeno 96 de Linfócito/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Monócitos/citologia , Monócitos/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismo
16.
Molecules ; 24(9)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31052263

RESUMO

Edible coatings and films (ECF) are employed as matrixes for incorporating antimicrobial nanoparticles (NPs), and then they are applied on the fruits and vegetables to prolong shelf life and enhance storage quality. This paper provides a comprehensive review on the preparation, antimicrobial properties and mechanisms, surface and physical qualities of ECF containing antimicrobial NPs, and its efficient application to vegetables and fruits as well. Following an introduction on the properties of the main edible coating materials, the preparation technologies of ECF with NPs are summarized. The antimicrobial activity of ECF with NPs against the tested microorganism was observed by many researchers. This might be mainly due to the electrostatic interaction between the cationic polymer or free metal ions and the charged cell membrane, the photocatalytic reaction of NPs, the detachment of free metal ion, and partly due to the antimicrobial activity of edible materials. Moreover, their physical, mechanical and releasing properties are discussed in detail, which might be influenced by the concentration of NPs. The preservation potential on the quality of fruits and vegetables indicates that various ECF with NPs might be used as the ideal materials for food application. Following the introduction on these characteristics, an attempt is made to predict future trends in this field.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Conservação de Alimentos , Frutas , Nanopartículas/química , Verduras , Fenômenos Químicos , Quitosana , Embalagem de Alimentos , Conservação de Alimentos/métodos , Conservantes de Alimentos , Fenômenos Mecânicos , Estrutura Molecular
17.
J Food Sci ; 84(6): 1411-1419, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31132162

RESUMO

To improve the mechanical and antibacterial properties of chitosan (CS) films, a ternary blend edible film was prepared by incorporating CS, gelatin (GE), and natural cinnamon essential oil (CEo). Scanning electron microscopy (SEM), Atomic force microscopy (AFM), Fourier transform infrared spectroscopy, and X-ray diffraction were performed to evaluate the films. The mechanical properties, light transmission, thermal stability, hydrophilicity, and antibacterial activity of the films were also determined. The results confirmed all of the films exhibited excellent UV protection with low transparency at 600 nm. Compared with the CS films, the ternary composite film (CSGEo film, containing CS, GE, and CEo) had a higher elongation at break but a lower tensile strength. SEM images revealed that all films had smooth surfaces, although some obvious differences between CS and CSGEo films were observed by AFM. Additionally, the incorporation of GE and CEo to the films enhanced their thermal stability and contact angle, but decreased their crystallinity and wettability. The antimicrobial activity results showed that CSGEo films had excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, for which the antibacterial rate exceeded 98%. The minimum inhibitory concentrations of the CSGEo solution against E. coli and S. aureus were both 52.06 µg/mL, and the minimal bactericidal concentrations were 104.12 and 52.06 µg/mL, respectively. These results suggest that CSGEo films possess good mechanical and antibacterial properties, and therefore, their application in the food packaging industry is promising. PRACTICAL APPLICATION: The main raw materials of the edible films developed in this study are aquatic by-products, so the films are edible and biodegradable. The addition of gelatin and CEo improved the UV barrier and thermal properties but decreased the crystallinity and hydrophilicity of the films, making them suitable for use as packaging materials. CEo-incorporated films exhibited excellent mechanical properties and antibacterial activity and can, therefore, be used in the food packaging industry.


Assuntos
Anti-Infecciosos , Quitosana , Embalagem de Alimentos/instrumentação , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Quitosana/química , Cinnamomum zeylanicum/química , Escherichia coli/efeitos dos fármacos , Embalagem de Alimentos/métodos , Gelatina/química , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Óleos Voláteis , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração , Difração de Raios X
18.
ChemSusChem ; 12(15): 3642-3653, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31081279

RESUMO

Twelve new quaternary ammonium sophorolipids with long alkyl chains on the nitrogen atom were synthesized starting from oleic and petroselinic acid-based sophorolipids. These novel derivatives were evaluated for their antimicrobial activity against selected Gram-negative and Gram-positive bacteria and their transfection efficacies on three different eukaryotic cell lines in vitro as good activities were demonstrated for previously synthesized derivatives. Self-assembly properties were also evaluated. All compounds proved to possess antimicrobial and transfection properties, and trends could be observed based on the length of the nitrogen substituent and the total length of the sophorolipid tail. Moreover, all long-chain quaternary ammonium sophorolipids form micelles, which proved to be a prerequisite to induce antimicrobial activity and transfection capacity. These results are promising for future healthcare applications of long-chained quaternary ammonium sophorolipids.


Assuntos
Anti-Infecciosos/química , Lipídeos/química , Compostos de Amônio Quaternário/química , Transfecção , Anti-Infecciosos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Micelas , Testes de Sensibilidade Microbiana , Compostos de Amônio Quaternário/farmacologia , Relação Estrutura-Atividade
19.
Int J Mol Sci ; 20(10)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091773

RESUMO

The gut microbiome has important effects on gastrointestinal diseases. Diarrhea attenuation functions of baicalin (BA) is not clear. Baicalin-aluminum complexes (BBA) were synthesized from BA, but the BBA's efficacy on the diarrhea of piglets and the gut microbiomes have not been explored and the mechanism remains unclear. This study has explored whether BBA could modulate the composition of the gut microbiomes of piglets during diarrhea. The results showed that the diarrhea rate reduced significantly after treatment with BBA. BBA altered the overall structure of the gut microbiomes. In addition, the Gene Ontology (GO) enrichment analysis indicated that the functional differentially expressed genes, which were involved in the top 30 GO enrichments, were associated with hydrogenase (acceptor) activity, nicotinamide-nucleotide adenylyltransferase activity, and isocitrate lyase activity, belong to the molecular function. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that flagellar assembly, bacterial chemotaxis, lipopolysaccharide biosynthesis, ATP-binding cassette transporters (ABC) transporters, biosynthesis of amino acids, and phosphotransferase system (PTS) were the most enriched during BBA treatment process. Taken together, our results first demonstrated that BBA treatment could modulate the gut microbiomes composition of piglets with diarrhea, which may provide new potential insights on the mechanisms of gut microbiomes associated underlying the antimicrobial efficacy of BBA.


Assuntos
Anti-Infecciosos/farmacologia , Fezes/microbiologia , Flavonoides/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Alumínio/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Diarreia/tratamento farmacológico , Diarreia/veterinária , Flavonoides/química , Flavonoides/uso terapêutico , Suínos , Doenças dos Suínos/tratamento farmacológico
20.
Mar Drugs ; 17(5)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052556

RESUMO

Six new diketopiperazines, (±)-7,8-epoxy-brevianamide Q ((±)-1), (±)-8-hydroxy-brevianamide R ((±)-2), and (±)-8-epihydroxy-brevianamide R ((±)-3), together with four known compounds, (±)-brevianamide R ((±)-4), versicolorin B (5) and averufin (6), were isolated from a marine-derived fungus strain Aspergillus versicolor MF180151, which was recovered from a sediment sample collected from the Bohai Sea, China. The chemical structures were established by 1D- and 2D-NMR spectra and HR-ESI-MS. 1 is the first sample of brevianamides with an epoxy moiety. Their bioactivities were evaluated against Candida albicans, Bacillus subtilis, Staphylococcus aureus, methicillin-resistant S. aureus, Pseudomonas aeruginosa, and Bacillus Calmette-Guérin. Compounds 1-4 showed no activities against the pathogens, and compounds 5 and 6 showed moderate activities against S. aureus and methicillin-resistant S. aureus.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Aspergillus/química , Dicetopiperazinas/química , Dicetopiperazinas/farmacologia , Anti-Infecciosos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , China , Dicetopiperazinas/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
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