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1.
Int J Biol Macromol ; 259(Pt 1): 129222, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185307

RESUMO

The substantial nutritional content and diversified biological activity of plant-based nutraceuticals are due to polyphenolic chemicals. These chemicals are important and well-studied plant secondary metabolites. Their protein interactions are extensively studied. This relationship is crucial for the logical development of functional food and for enhancing the availability and usefulness of polyphenols. This study highlights the influence of protein types and polyphenols on the interaction, where the chemical bindings predominantly consist of hydrophobic interactions and hydrogen bonds. The interaction between polyphenolic compounds (PCs) and digestive enzymes concerning their inhibitory activity has not been fully studied. Therefore, we have examined the interaction of four digestive enzymes (α-amylase, pepsin, trypsin, and α-chymotrypsin) with four PCs (curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone) through in silico and in vitro approaches. In vitro plate assays, enzyme kinetics, spectroscopic assays, molecular docking, and simulations were performed. We observed all these PCs have significant docking scores and preferable interaction with the active site of the digestive enzymes, resulting in the reduction of enzyme activity. The enzyme-substrate binding mechanism was determined using the Lineweaver Burk plot, indicating that the inhibition occurred competitively. Among four PCs diosmin and morin has the highest interaction energy over digestive enzymes with IC50 value of 1.13 ± 0.0047 and 1.086 ± 0.0131 µM. Kinetic studies show that selected PCs inhibited pepsin, trypsin, and chymotrypsin competitively and inhibited amylase in a non-competitive manner, especially by 2',3',4'-trihydroxychalcone. This study offers insights into the mechanisms by which the selected PCs inhibit the enzymes and has the potential to enhance the application of curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone as natural inhibitors of digestive enzymes.


Assuntos
Curcumina , Diosmina , Simulação de Acoplamento Molecular , Pepsina A/metabolismo , Tripsina/metabolismo , Curcumina/farmacologia , Cinética , Polifenóis/farmacologia , Flavonoides/farmacologia , Flavonoides/química , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
2.
Curr Med Chem ; 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37877148

RESUMO

Edible oils are inevitable requisites in the human diet as they are enriched with essential fatty acids, vitamins, carotenoids, sterols, and other antioxidants. Due to their nutritive value and commercial significance, edible oils have been used for food preparation for many centuries. The use of global consumption of edible oils has dramatically increased throughout the world in the 21st century owing to their incredible application in all kinds of food preparation. However, a variety of pollutants, such as pesticides, toxic chemicals, heavy metals, and environmental pollution, have contributed to the contamination of edible oils. Furthermore, the benzophenanthridine alkaloids, sanguinarine, dihydrosanguinarine, butter yellow, and other several agents are added intentionally, which are known to cause a number of human diseases. Apart from this, repeated heating and reusing of oils results in trans fats, and lipid peroxidation alters the fatty acid composition, which adversely affects the health of consumers and increases the risk of cardiovascular diseases. Moreover, the prevention of edible oil contamination in human health at various levels is inevitable to ensure consumer safety. Hence, the present review provides an overview of vegetable cooking oils and the health ailments that detection techniques are focused on.

3.
Crit Rev Anal Chem ; 53(8): 1828-1839, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35201946

RESUMO

Biomarkers are biological molecules associated with physiological changes of the body and aids in the detecting the onset of disease in patients. There is an urgent need for self-monitoring and early detection of cardiovascular and other health complications. Several blood-based biomarkers have been well established in diagnosis and monitoring the onset of diseases. However, the detection level of biomarkers in bed-side analysis is difficult and complications arise due to the endothelial dysfunction. Currently single volatile organic compounds (VOCs) based sensors are available for the detection of human diseases and no dedicated nanosensor is available for the elderly. Moreover, accuracy of the sensors based on a single analyte is limited. Hence, breath analysis has received enormous attention in healthcare due to its relatively inexpensive, rapid, and noninvasive methods for detecting diseases. This review gives a detailed analysis of how biomarker imprinted nanosensor can be used as a noninvasive method for detecting VOC to health issues early using exhaled breath analysis.


Assuntos
Compostos Orgânicos Voláteis , Humanos , Idoso , Compostos Orgânicos Voláteis/análise , Biomarcadores , Testes Respiratórios/métodos
4.
Biotechnol Appl Biochem ; 70(2): 581-591, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35765758

RESUMO

Myocardial infarction (MI) is highly related to cardiac arrest leading to death and organ damage. Radiological techniques and electrocardiography have been used as preliminary tests to diagnose MI; however, these techniques are not sensitive enough for early-stage detection. A blood biomarker-based diagnosis is an immediate solution, and due to the high correlation of troponin with MI, it has been considered to be a gold-standard biomarker. In the present research, the cardiac biomarker troponin I (cTnI) was detected on an interdigitated electrode sensor with various surface interfaces. To detect cTnI, a capture aptamer-conjugated gold nanoparticle probe and detection antibody probe were utilized and compared through an alternating sandwich pattern. The surface metal oxide morphology of the developed sensor was proven by microscopic assessments. The limit of detection with the aptamer-gold-cTnI-antibody sandwich pattern was 100 aM, while it was 1 fM with antibody-gold-cTnI-aptamer, representing 10-fold differences. Further, the high performance of the sensor was confirmed by selective cTnI determination in serum, exhibiting superior nonfouling. These methods of determination provide options for generating novel assays for diagnosing MI.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Infarto do Miocárdio , Humanos , Troponina I , Ouro , Limite de Detecção , Óxidos , Infarto do Miocárdio/diagnóstico , Anticorpos , Técnicas Biossensoriais/métodos , Biomarcadores , Técnicas Eletroquímicas/métodos , Imunoensaio
5.
Front Chem ; 10: 984218, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212054

RESUMO

Nanoscale iron oxide-based nanostructures are among the most apparent metallic nanostructures, having great potential and attracting substantial interest due to their unique superparamagnetic properties. The green production of nanostructures has received abundant attention and been actively explored recently because of their various beneficial applications and properties across different fields. The biosynthesis of the nanostructure using green technology by the manipulation of a wide variety of plant materials has been the focus because it is biocompatible, non-toxic, and does not include any harmful substances. Biological methods using agro-wastes under green synthesis have been found to be simple, environmentally friendly, and cost-effective in generating iron oxide-based nanostructures instead of physical and chemical methods. Polysaccharides and biomolecules in agro-wastes could be utilized as stabilizers and reducing agents for the green production of nanostructured iron oxide towards a wide range of benefits. This review discusses the green production of iron oxide-based nanostructures through a simple and eco-friendly method and its potential applications in medical and sustainable agro-environments. This overview provides different ways to expand the usage of iron oxide nanomaterials in different sectors. Further, provided the options to select an appropriate plant towards the specific applications in agriculture and other sectors with the recommended future directions.

6.
Int J Pept Res Ther ; 28(5): 135, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911180

RESUMO

Biologically active plant peptides, consisting of secondary metabolites, are compounds (amino acids) utilized by plants in their defense arsenal. Enzymatic processes and metabolic pathways secrete these plant peptides. They are also known for their medicinal value and have been incorporated in therapeutics of major human diseases. Nevertheless, its limitations (low bioavailability, high cytotoxicity, poor absorption, low abundance, improper metabolism, etc.) have demanded a need to explore further and discover other new plant compounds that overcome these limitations. Keeping this in mind, therapeutic plant proteins can be excellent remedial substitutes for bodily affliction. A multitude of these peptides demonstrates anti-carcinogenic, anti-microbial, anti-HIV, and neuro-regulating properties. This article's main aim is to list out and report the status of various therapeutic plant peptides and their prospective status as peptide-based drugs for multiple diseases (infectious and non-infectious). The feasibility of these compounds in the imminent future has also been discussed.

7.
Int J Biol Macromol ; 217: 633-651, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35843398

RESUMO

The effects of different incubation periods on the contents of amino acids, proteins, glycosylated proteins and metabolites in germinated and ungerminated mung bean seeds were investigated in this study. The study employs soaking of mung bean seeds in water under laboratory conditions at 28 °C for 3, 6, and 9 h, followed by germination for 12, 24, 36, and 48 h. Seeds collected from different period of imbibition and germination were subjected to total protein extraction for phytochemical analysis. Germination of the seeds was found to be most successful after 6 h of soaking (rather than 9 h of incubation). Hence, seeds imbibed for 6 h were further investigated for germination at 28 °C for 12, 24, 36, and 48 h. Total protein was extracted from both imbibed and germinated seeds, followed by trypsin digestion. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based peptide mass fingerprinting revealed 38 proteins in 6 h water-imbibed seeds and 50 proteins in 24 h germinated seeds. Among these, 16 were identified as glycosylated proteins and the maximum number of glycosylated proteins were detected in 6 h water-imbibed seeds and 24 h germinated seeds. Moreover, High Performance Liquid Chromatography (HPLC) was used to quantify amino acids from the extracted proteins. A total of 15 amino acids were detected, of which eight were essential and the remaining were non-essential; amino acid concentrations increased following 3, 6, and 9 h of imbibition when compared to the control. It was concluded from the study that seeds with 6 h of imbibition and 24 h of germination can be used as potential nutritional source of different amino acids, proteins, glycosylated proteins, and other bioactive metabolites in human diet.


Assuntos
Fabaceae , Vigna , Aminoácidos/metabolismo , Cromatografia Líquida , Fabaceae/química , Germinação , Humanos , Sementes/química , Espectrometria de Massas em Tandem , Água/metabolismo
8.
Biosensors (Basel) ; 12(6)2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35735537

RESUMO

Salmonellosis caused by Salmonella sp. has long been reported all over the world. Despite the availability of various diagnostic methods, easy and effective detection systems are still required. This report describes a dialysis membrane electrode interface disc with immobilized specific antibodies to capture antigenic Salmonella cells. The interaction of a specific Salmonella antigen with a mouse anti-Salmonella monoclonal antibody complexed to rabbit anti-mouse secondary antibody conjugated with HRP and the substrate o-aminophenol resulted in a response signal output current measured using two electrode systems (cadmium reference electrode and glassy carbon working electrode) and an agilent HP34401A 6.5 digital multimeter without a potentiostat or applied potential input. A maximum response signal output current was recorded for various concentrations of Salmonella viz., 3, 30, 300, 3000, 30,000 and 300,000 cells. The biosensor has a detection limit of three cells, which is very sensitive when compared with other detection sensors. Little non-specific response was observed using Streptococcus, Vibrio, and Pseudomonas sp. The maximum response signal output current for a dialysis membrane electrode interface disc was greater than that for gelatin, collagen, and agarose. The device and technique have a range of biological applications. This novel detection system has great potential for future development and application in surveillance for microbial pathogens.


Assuntos
Técnicas Biossensoriais , Salmonella typhimurium , Animais , Anticorpos Imobilizados , Técnicas Biossensoriais/métodos , Eletrodos , Camundongos , Coelhos
9.
Artigo em Inglês | MEDLINE | ID: mdl-35609808

RESUMO

The goal of this study was to assess the efficacy of probiotics in mitigating ammonia-induced toxicity in fish. Fish were divided into four groups: control, only probiotic, only ammonia, and combined ammonia + probiotic. For 8 weeks, the Oreochromis mossambicus were exposed to waterborne ammonia at 1.0 mg L-1 and/or dietary Bacillus licheniformis Dahb1 at 107 cfu g-1. After the 4th and 8th weeks, the fish were evaluated for growth performance, enzymatic and non-enzymatic antioxidant activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) reduced glutathione (GSH), neurotoxicity (acetylcholinesterase - AChE), non-specific immune responses (lysozyme (LYZ), myeloperoxidase (MPO), reactive nitrogen and oxygen species (RNS and ROS) and oxidative stress effects (lipid peroxidation (LPO), DNA damage)). Our results showed that in the absence of waterborne ammonia exposure, B. licheniformis Dahb1 significantly improved growth performance, enzymatic and non-enzymatic antioxidant capacity, AChE activity, non-specific immune response and decreased oxidative stress effect. Ammonia exposure resulted in significantly lower growth performance, reduced enzymatic and non-enzymatic antioxidant ability, decreased AChE activity, decreased non-specific immune response and increased oxidative stress effect. When O. mossambicus were exposed to ammonia, supplementation with B. licheniformis Dahb1 in the diet significantly increased survival, indicating that it may have a significant protective effect against ammonia toxicity by enhancing enzymatic and non-enzymatic antioxidant ability, activity of AChE, non-specific immune response and reduced oxidative stress effect. According to our findings, diet supplementation of B. licheniformis Dahb1 (107 cfu g-1) has the potential to combat ammonia toxicity in O. mossambicus.


Assuntos
Bacillus licheniformis , Probióticos , Tilápia , Acetilcolinesterase , Amônia/toxicidade , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Bacillus licheniformis/metabolismo , Estresse Oxidativo , Probióticos/farmacologia
10.
Front Biosci (Landmark Ed) ; 27(4): 123, 2022 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-35468682

RESUMO

COVID-19, caused by the severe acquired respiratory syndrome coronavirus-2 (SARS-CoV-2), is a highly contagious disease that has emerged as a pandemic. Researchers and the medical fraternity are working towards the identification of anti-viral drug candidates. Meanwhile, several alternative treatment approaches are being explored to manage the disease effectively. Various phyto-drugs and essential oils have been reported to have antiviral activity, but this has not been well studied in the context of SARS-CoV-2. The main focus of this review is on the biology of infection and the different therapeutic strategies involved, including drug repurposing and phytopharmaceuticals. The role of phytochemicals in treating COVID-19 and various other diseases has also been emphasized.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Antivirais/uso terapêutico , Humanos , SARS-CoV-2
11.
Biotechnol Appl Biochem ; 69(2): 714-725, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33751641

RESUMO

Overuse of antibiotics has led to the development of multidrug-resistant strains. Antibiotic resistance is a major drawback in the biomedical field since medical implants are prone to infection by biofilms of antibiotic resistant strains of bacteria. With increasing prevalence of antibiotic-resistant pathogenic bacteria, the search for alternative method is utmost importance. In this regard, magnetic nanoparticles are commonly used as a substitute for antibiotics that can circumvent the problem of biofilms growth on the surface of biomedical implants. Iron oxide nanoparticles (IONPs) have unique magnetic properties that can be exploited in various ways in the biomedical applications. IONPs are engineered employing different methods to induce surface functionalization that include the use of polyethyleneimine and oleic acid. IONPs have a mechanical effect on biofilms in presence of an external magnet. In this review, a detailed description of surface-engineered magnetic nanoparticles as ideal antibacterial agents is provided, accompanied by various methods of literature review.


Assuntos
Biofilmes , Nanopartículas , Antibacterianos/farmacologia , Nanopartículas Magnéticas de Óxido de Ferro
12.
J King Saud Univ Sci ; 33(8): 101648, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34690467

RESUMO

SARS-CoV2 is a member of human coronaviruses and is the causative agent of the present pandemic COVID-19 virus. In order to control COVID-19, studies on viral structure and mechanism of infectivity and pathogenicity are sorely needed. The spike (S) protein is comprised of S1 & S2 subunits. These spike protein subunits enable viral attachment by binding to the host cell via ACE-2 (angiotensin converting enzyme-2) receptor, thus facilitating the infection. During viral entry, one of the key steps is the cleavage of the S1-S2 spike protein subunits via surface TMPRSS2 (transmembrane protease serine 2) and results in viral infection. Hence, the S-protein is critical for the viral attachment and penetration into the host. The rapid advancement of our knowledge on the structural and functional aspects of the spike protein could lead to development of numerous candidate vaccines against SARS-CoV2. Here the authors discuss about the structure of spike protein and explore its related functions. Our aim is to provide a better understanding that may aid in fighting against CoVID-19 and its treatment.

13.
Heliyon ; 7(5): e07021, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34036196

RESUMO

Nosocomial pathogens cause various health problems in human and many novel drugs are under investigation to combat the pathogens. The present study explains the naturally derived hydroquinone possible mode of action against Pseudomonas aeruginosa MTCC 741 and Staphylococcus aureus MTCC 740. Time kill studies, cell viability assays, membrane potential assays, and potassium release assays were carried out to study the mode of action. Time kill studies revealed the rapid death of bacterial pathogens exposed to 4X MIC (Minimum inhibitory concentration) of the hydroquinone. Cell viability assay results showed that nearly half of the cell destruction of test pathogens occurred within one hour. Transmission electron microscopic (TEM) observations revealed the disruption of the cell membrane, which caused severe ultrastructural changes in both test pathogens. Hydroquinone dissipated the membrane potential of test pathogens, as confirmed by the depolarization of membrane potential, increases in permeability and leakage of intracellular potassium ions. At the concentration of 2X MIC hydroquinone in 5 min, about 91.41% and 84.85% potassium ions were released from P. aeruginosa MTCC 741 and S. aureus MTCC 740, respectively. This is the first report on the mode of action of naturally derived hydroquinone against clinical pathogens.

14.
PLoS One ; 13(3): e0193717, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29494663

RESUMO

Enzyme hydrolysates (trypsin, papain, pepsin, α-chymotrypsin, and pepsin-pancreatin) of Tinospora cordifolia stem proteins were analyzed for antioxidant efficacy by measuring (1) 1,1-diphenyl-2-picrylhydrazyl (DPPH•) radical scavenging activity, (2) 2,20-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) radical scavenging capacity, and (3) Fe2+ chelation. Trypsin hydrolysate showed the strongest DPPH• scavenging, while α-chymotrypsin hydrolysate exhibited the highest ABTS+ scavenging and Fe2+ chelation. Undigested protein strongly inhibited the gastrointestinal enzymes, trypsin (50% inhibition at enzyme/substrate ratio = 1:6.9) and α-chymotrypsin (50% inhibition at enzyme/substrate ratio = 1:1.82), indicating the prolonged antioxidant effect after ingestion. Furthermore, gel filtration purified peptide fractions of papain hydrolysates exhibited a significantly higher ABTS+ and superoxide radical scavenging as compared to non-purified digests. Active fraction 9 showing the highest radical scavenging ability was further purified and confirmed by MALDI-TOF MS followed by MS/MS with probable dominant peptide sequences identified are VLYSTPVKMWEPGR, VITVVATAGSETMR, and HIGININSR. The obtained results revealed that free radical scavenging capacity of papain hydrolysates might be related to its consistently low molecular weight hydrophobic peptides.


Assuntos
Sequestradores de Radicais Livres/análise , Peptídeos/análise , Tinospora/química , Antioxidantes , Quimotripsina/metabolismo , Sequestradores de Radicais Livres/química , Hidrólise , Papaína/metabolismo , Pepsina A/metabolismo , Peptídeos/química , Extratos Vegetais/análise , Extratos Vegetais/química , Tripsina/metabolismo
15.
Int J Biol Macromol ; 114: 864-873, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29601878

RESUMO

In this study, we purified ß-GBP from hemolymph of Scylla serrata crabs using affinity chromatography. The purified S. serrata ß-GBP (Ss-ß-GBP) had 100kDa molecular mass in the SDS-PAGE. MALDI-TOF/TOF analysis was conducted, revealing that the purified 100kDa protein had 96% similarity with ß-GBP of Astacus leptodactylus. Ss-ß-GBP was characterized using high-performance liquid chromatography (HPLC), X-ray diffraction (XRD) analysis, circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopy, which confirmed the structure of the Ss-ß-GBP. The purified Ss-ß-GBP was functionally analyzed by yeast agglutination and phagocytic reaction assays. Moreover, the PO enhancing ability of Ss-ß-GBP was evidenced through PO activity. Specifically, the antibacterial activity of the Ss-ß-GBP against Gram-positive (Enterococcus faecalis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria was evaluated by determining its minimum inhibitory concentration (MIC)<60µg/ml for all tested species. Furthermore, the antibiofilm efficacy of Ss-ß-GBP at 50 and 100µg/ml was outlined using light microscopy and confocal laser scanning microscopy (CLSM). Bacterial viability assays also outlined the dose-dependent activity of Ss-ß-GBP based on the ratio of live/dead bacterial cells. The results of this study revealed that crab-borne Ss-ß-GBP might be widely used to suppress the growth of pathogenic bacteria.


Assuntos
Antibacterianos/química , Biofilmes/efeitos dos fármacos , Braquiúros/química , Proteínas de Transporte/isolamento & purificação , Hemolinfa/química , Lectinas/isolamento & purificação , Monofenol Mono-Oxigenase/metabolismo , Sequência de Aminoácidos , Animais , Antibacterianos/isolamento & purificação , Proteínas de Transporte/química , Proteínas de Transporte/farmacologia , Técnicas de Química Analítica , Cromatografia de Afinidade , Composição de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Glucanos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Lectinas/química , Lectinas/farmacologia , Testes de Sensibilidade Microbiana , Fagocitose/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos
16.
Indian J Microbiol ; 56(2): 148-57, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27570306

RESUMO

The aim of this study was to purify, characterize and evaluate the antibacterial activity of bioactive compound against methicillin-resistant Staphylococcus aureus (MRSA). The anti-MRSA compound was produced by a halophilic bacterial strain designated as MHB1. The MHB1 strain exhibited 99 % similarity to Bacillus amyloliquefaciens based on 16S rRNA gene analysis. The culture conditions of Bacillus amyloliquefaciens MHB1 were optimized using nutritional and environmental parameters for enhanced anti-MRSA compound production. The pure bioactive compound was isolated using silica gel column chromatography and Semi-preparative High-performance liquid chromatography (Semi-preparative HPLC). The Thin layer chromatography, Fourier transform infrared spectroscopy and proton NMR ((1)H NMR) analysis indicated the phenolic nature of the compound. The molecular mass of the purified compound was 507 Da as revealed by Liquid chromatography-mass spectrometry (LC-MS) analysis. The compound inhibited the growth of MRSA with minimum inhibitory concentration (MIC) of 62.5 µg mL(-1). MRSA bacteria exposed to 4× MIC of the compound and the cell viability was determined using flow cytometric analysis. Scanning electron microscope and Transmission electron microscope analysis was used to determine the ultrastructural changes in bacteria. This is the first report on isolation of anti-MRSA compound from halophilic B. amyloliquefaciens MHB1 and could act as a promising biocontrol agent.

17.
Biofouling ; 32(8): 861-70, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27436679

RESUMO

Bacterial adhesion is a major problem that can lead to the infection of implanted urological stents. In this study, kanamycin-chitosan nanoparticles (KMCSNPs) were immobilized on the surface of a polyurethane ureteral stent (PUS) to prevent urinary bacterial infection. KMCSNPs were synthesized using the ionic gelation method. The synthesized KMCSNPs appeared spherical with a ζ-average particle size of 225 nm. KMCSNPs were immobilized on the PUS surface by covalent immobilization techniques. The surface-modified PUS was characterized using attenuated total reflectance Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and energy dispersive X-ray spectroscopy. The surface-modified PUS showed significantly increased antibacterial activity against Escherichia coli MTCC 729 and Proteus mirabilis MTCC 425 relative to the surface of an unmodified PUS. These findings suggest that the KMCSNP-immobilized PUS has the potential to prevent bacterial infection in the human urinary tract.


Assuntos
Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Quitosana/química , Canamicina/farmacologia , Nanopartículas/química , Poliuretanos/química , Stents/microbiologia , Ureter/microbiologia , Antibacterianos/química , Humanos , Canamicina/química , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Infecções Urinárias/prevenção & controle
18.
PLoS One ; 11(6): e0157612, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27304672

RESUMO

In the current study, facile synthesis of carboxymethyl cellulose (CMC) and sodium alginate capped silver nanoparticles (AgNPs) was examined using microwave radiation and aniline as a reducing agent. The biopolymer matrix embedded nanoparticles were synthesized under various experimental conditions using different concentrations of biopolymer (0.5, 1, 1.5, 2%), volumes of reducing agent (50, 100, 150 µL), and duration of heat treatment (30 s to 240 s). The synthesized nanoparticles were analyzed by scanning electron microscopy, UV-Vis spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy for identification of AgNPs synthesis, crystal nature, shape, size, and type of capping action. In addition, the significant antibacterial efficacy and antibiofilm activity of biopolymer capped AgNPs were demonstrated against different bacterial strains, Staphylococcus aureus MTCC 740 and Escherichia coli MTCC 9492. These results confirmed the potential for production of biopolymer capped AgNPs grown under microwave irradiation, which can be used for industrial and biomedical applications.


Assuntos
Antibacterianos/química , Biofilmes/crescimento & desenvolvimento , Biopolímeros/química , Nanopartículas Metálicas/química , Micro-Ondas , Prata/química , Antibacterianos/toxicidade , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Nanopartículas Metálicas/efeitos da radiação , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Difração de Raios X
19.
Toxicol Res ; 32(2): 95-102, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27123159

RESUMO

In the recent years, noble nanoparticles have attracted and emerged in the field of biology, medicine and electronics due to their incredible applications. There were several methods have been used for synthesis of nanoparticles such as toxic chemicals and high energy physical procedures. To overcome these, biological method has been used for the synthesis of various metal nanoparticles. Among the nanoparticles, silver nanoparticles (AgNPs) have received much attention in various fields, such as antimicrobial activity, therapeutics, bio-molecular detection, silver nanocoated medical devices and optical receptor. Moreover, the biological approach, in particular the usage of natural organisms has offered a reliable, simple, nontoxic and environmental friendly method. Hence, the current article is focused on the biological synthesis of silver nanoparticles and their application in the biomedical field.

20.
Microb Pathog ; 93: 70-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26802520

RESUMO

In the present study, we synthesized and characterized a probiotic Bacillus licheniformis cell free extract (BLCFE) coated silver nanoparticles (BLCFE-AgNPs). These BLCFE-AgNPs were characterized by UV-visible spectrophotometer, XRD, EDX, FTIR, TEM and AFM. A strong surface plasmon resonance centered at 422 nm in UV-visible spectrum indicates the formation of AgNPs. The XRD spectrum of silver nanoparticles exhibited 2θ values corresponding to the silver nanocrystal. TEM and AFM showed the AgNPs were spherical in shape within the range of 18.69-63.42 nm and the presence of silver was confirmed by EDX analysis. Light and Confocal Laser Scanning Microscope (CLSM) images showed a weak adherence and disintegrated biofilm formation of Vibrio parahaemolyticus Dav1 treated with BLCFE-AgNPs compared to control. This result suggests that BLCFE-AgNps may be used for the control of biofilm forming bacterial populations in the biomedical field. In addition, acute toxicity results concluded that BLCFE-AgNPs were less toxic to the fresh water crustacean Ceriodaphnia cornuta (50 µg/ml) when compared to AgNO3 (22 µg/ml). This study also reports a short term analysis (24 h) of uptake and depuration of BLCFE-AgNPs in C. cornuta.


Assuntos
Bacillus licheniformis/metabolismo , Biofilmes/efeitos dos fármacos , Sistema Livre de Células/metabolismo , Crustáceos/efeitos dos fármacos , Nanopartículas/toxicidade , Prata/metabolismo , Vibrio parahaemolyticus/efeitos dos fármacos , Animais , Bacillus licheniformis/química , Bacillus licheniformis/genética , Sistema Livre de Células/química , Crustáceos/crescimento & desenvolvimento , Nanopartículas/análise , Probióticos/química , Probióticos/metabolismo , Prata/toxicidade , Vibrio parahaemolyticus/fisiologia
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