Biosynthesis and characterization of silver nanoparticles produced with aqueous extract of Pterodon emarginatus Vogel - Fabaceae seeds associated with gentamicin sulfate and hyaluronic acid with potential antimicrobial activity / Biossíntese e caracterização de nanopartículas de prata produzidas com extrato aquoso de sementes de Pterodon emarginatus Vogel - Fabaceae associadas ao sulfato de gentamicina e ao Ácido Hialurônico com potencial atividade antimicrobiana

The synthesis of metallic nanoparticles by biological systems is known as green synthesis or biosynthesis. In this synthesis strategy, instead of using toxic agents to reduce the metal ion, obtaining the metallic nanoparticles (NPs) is mediated by biological components capable of reducing the metal. In this context, the present work uses aqueous extract from the seeds of Pterodon emarginatus Vogel to obtain silver nanoparticles (AgNPs-PE). These metallic nanoparticles associated with the aqueous extract of P. emarginatus have, among others, antimicrobial property that was enhanced by the association of 1% gentamicin sulfate (AgNPs-PEG) and hyaluronic acid (AgNPs-PEG-AH2). Therefore, the evaluation of antimicrobial activity was addressed after obtaining the AgNPs-PE and their associations. The characterization of AgNPs-PE was performed by means of UV-Vis spectrophotometry, determination of the average hydrodynamic diameter (AHD), zeta potential (ZP) and polydispersity index (PDI), field emission gun scanning electron microscopy (FEG-SEM), energy dispersive X-ray spectroscopy (EDS) and Fourier transform infrared (FTIR) spectroscopy. Although the green synthesis still does not have its mechanisms clearly elucidated, it is known that the bioreduction of Ag+ and the stabilization of Ag0 are carried out by a combination of primary and secondary metabolites present in the extract, such as tannins and flavonoids. After formed, AgNPs-PE, AgNPs-PEG and AgNPs-PEG-AH2 showed, respectively, maximum absorbance around 423 nm, 425 nm and 430 nm. Microscopy (FEG-SEM) showed spherical-shaped nanoparticles, with an average size ranging from 59 nm for AgNPs-PE, 63 nm for AgNPs-PEG and 66 nm for AgNPs-PEG-AH2. The ZP of all AgNPs-PE and their associations remained within the values considered stable for nanoparticles (-27.15 to -39.73 mV). The PDI of the analyzed samples was on average 0.332 to 0.524, median values for the distribution of NPs. AgNPs-PE, AgNPs-PEG and AgNPs-PEG-AH2 showed bactericidal activity against Gram-positive, Gram-negative and yeast bacteria. The present research indicates that AgNPs-PE and their associations have potential as a therapeutic agent against bacterial and fungal infections

Development and validation of an RP-HPLC/UV Method for Determination of Cholecalciferol in Polymeric Nanoparticles Suspensions / Desenvolvimento e validação de um método RP-HPLC/UV para determinação do Cholecalciferol em nanopartículas poliméricas Suspensões

A simple and effective RP-HPLC/UV method was developed to determine cholecalciferol (COL) in suspensions of polymeric nanoparticles. Chromatographic conditions used in the methodology were a C18 RP column using an isocratic mobile phase of methanol and water (98:2 v/v) at a flow rate of 1.2 mL/min, UV detection at 265 nm. The validation parameters evaluated were: specificity, linearity, limit of quantification, limit of detection, precision, precision and robustness. The retention time was about 7.5 min. The method was linear, specific (r=0.9992) interval 10.0 to 80.0 ?g/mL, the limit of quantification (LOQ) was 0.52 ?g/mL and the limit of detection was 0.15 ?g/mL. Intermediate precision was evaluated, expressed as inter-day variation (RSD = 1.13) and intra-day (RSD = 1.16). The accuracy obtained was the recovery of 102.87 ± 9.84, considering the exact method proposed. To evaluate the robustness, the results showed little variation, concluding that a robust method. The method was fast, robust and suitable for quantification of suspensions of COL nanoparticles and can be used to evaluate the efficiency of COL encapsulation

Estimated Glomerular Filtration Rate (Egfr) In Elderly: A Comparison Between The Ckd-Epicreatinine And Biscreatinine Equations / Taxa da filtração glomerular estimada (tfge) em idosos: Comparação entre as equações ckd-epi-creatinina e bis-creatinina

Background: Aging is a risk factor for the development of chronic kidney disease (CKD). The estimation of the glomerular filtration rate (eGFR) is the most used method to assess renal function, influencing individualized therapeutic adjustment of medications eliminated by the kidneys. Objective: To compare the results obtained using two creatinine-based equations applied in older people: CKD-EPICreatinine and BISCreatinine; as well as evaluate the impact of these equations in the classification of the elderly in different stages of CKD. Materials and methods: An observational study was carried out in a long-term care facility, including subjects aged 70 years or older. Renal function was assessed by two equations: CKD-EPICreatinine and BISCreatinine. Statistical analysis included Kolmogorov-Smirnov, Wilcoxon, Spearman, and Bland-Altman tests. Staging of the level of renal function was performed according to the Kidney Disease: Improving Global Outcomes guidelines. Results: 73 patients with a mean age of 79.2 ± 6.1 years were evaluated. There was a significant decrease (p<0.001) in the eGFR obtained by the BISCreatinine equation in relation to CKD-EPICreatinine. Both equations showed strong correlation (r=0.96, p<0.001). The concordance analysis it was observed a bias of -13.6% (-33.5 to 6.3). From the mild-moderate reduction in renal function (3a stage), there was an increase in the number of elderly people classified in more advanced stages when assessed by BISCreatinine. Conclusion: BISCreatinine has been shown to underestimate the eGFR results, not showing full agreement from a clinical point of view for stratification of renal function with CKD-EPICreatinine in eGFR greater than 59 ml/min x 1,73m2

Evaluation of the Biotechnological Potential of Monteverdia salicifolia (Mart ex. Reissek) Biral

Plant extracts are a good alternative of reducing agents in the synthesis of metal nanoparticles. In this paper, we report the evaluation of the cytotoxic activity against T3 cell lines of the ethanolic extract of Monteverdia salicifolia (Mart ex. Reissek) Biral roots (MS) as well as a green one-pot route of synthesis of silver nanoparticles (AgNPs) using that extract as reducing and stabilizing agent. The extract exhibited dose dependent activity. The smallest particle size (48.01 nm) was achieved in just 25 minutes by employing a temperature of 65 °C and AgNO3 and MS concentrations equal to 0.9 mmol.L−1 and 0.67 mg.mL−1, respectively. The AgNPs-MS nanocomposite was characterized by UV–vis spectroscopy, FEG microscope and zeta potential, which proved that MS was effective at reducing and capping the AgNPs. In order to emphasize the advantage of the methodology applied in this synthesis, it was compared to a usual procedure using NaBH4 as a reducing agent and the greenness analysis was also carried out, using the Green Star. DOI: http://dx.doi.org/10.17807/orbital.v13i2.154

Study action repellents of oil essential the Ocimum selloi Benth Anopheles braziliensis Chagas

Made available in DSpace on 2012-09-06T01:11:45Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 481.pdf: 1732518 bytes, checksum: 5331df652b55c7dbbb5a4fa1087fe16f (MD5) Previous issue date: 2002Fundação Oswaldo Cruz. Escola Nacional de Saúde Pública Sergio Arouca. Rio de Janeiro, RJ, Brasil.Ocimum selloi Benth. (Lamieceae), também conhecida como "alfavaca", é uma planta herbácea que ocorre no Brasil. O óleo essencial obtido das suas folhas tem sido usado como aditivo aromatizante em alimentos, produtos odontológicos e como ingrediente de fragrâncias. Na medicina popular brasileira, o O. selloi tem sido amplamente empregado como remédio antiinflamatório e antiespasmódico e, também, para tratar diarréia. O principal objetivo deste estudo foi avaliar a atividade repelente de mosquitos e o potencial de irritação dérmica do óleo de O. selloi em voluntários. Além disso, foram obtidos também dados sobre o perfil toxicológico (toxicidade aguda oral data e mutagenicidade no teste de Ames), e sobre as propriedades físico-químicas e constituintes químicas e constituintes químicos do óleo essencial do O. selloi coletado em Ponta Grossa, estado do Paraná. O óleo essencial foi obtido por hidrodestilação de folhas de O. selloi. Os constituintes químicos foram determinados por Cromatoia em Camada Delgada (CCD) e GC-MS/MSD. Os principais constituintes do óleo volátil analisado por GC-MS/MSD foram o estragol (55,38 por cento) e o trans-anetol (34,23 por cento). O óleo de O. selloi foi agudamente tóxico e letal para camundongos (fêmeas mais suscetíveis que machos) em doses iguais ou superiores a 1500 mg/kg de peso corporal. Não foi observada atividade mutagênica em ensaios in vitro com as linhagens de Salmonella thyphimurium TA97a, TA98 e TA100, sem e com adição de mistura S9. Não foi constatada irritação dérmica no antebraço de 30 voluntários expostos ao O. selloi por 4 horas. No estudo de campo em que seis voluntários (cada indivíduo é seu próprio controle) foram expostos Anopheles brasiliensis por 30 minutos o O. selloi (solução 10 por cento p/v em etanol) reduziu drasticamente a freqüência de picadas em relação ao etanol (redução de 88 por cento, P=0,01) demonstrando que é um repelente eficaz.Ocimum selloi Benth. (Lamiaceae), also known as “alfavaca”, is an herbal plant native to Brazil. The essential oil obtained from its leaves has been used as a flavoring additive in foods, dental and oral products, and as an ingredient of fragrances. In the Brazilian traditional medicine O. selloi has been widely employed as an anti-inflammatory and anti-spasmodic remedy and, also, to treat diarrhea. The main objective of the present study was to evaluate the mosquito repellent activity and skin irritant potential ofO. selloi oil in humans. Furthermore, data were also provided on the toxicological profile (acute oral toxicity to mice and mutagenicity in the Ames’ test), and on the physicochemical properties as well as on the chemical constituents of the essential oil ofO. selloi grown in Ponta Grossa, Paraná state. The essential oil was obtained by hydro-distillation of O.selloi leaves. Chemical constituents were determined by Thin Layer Chromatography (TLC) and GC-MS/MSD. The main chemical constituents of the volatile oil analyzed by GC-MS/MSD were estragole (55,38%) and trans-anethole (34,23%). The O. selloi oil proved to be acutely toxic and lethal to mice (females more susceptible than males) at doses equal to or higher than 1500 mg/kg body wt. No mutagenicity was found in in vitro assays with Salmonella thyphimurium tester strains TA97a, TA98 and TA100, without and with addition of S9 mixture. No skin irritancy was noted in the forearms of 30 volunteers exposed to O. selloi oil for 4 hours. In a field study in which six volunteers (each individual is his own control) were exposed to Anopheles brasiliensis for 30 minutes, O. selloi (10% w/v solution in ethanol) drastically reduced the frequency of bites as compared to ethanol alone (reduction of 88%, P=0,01) thereby proving to be an effective mosquito repellent

Obtaining Ultrafine Dispersions of Silver Particles in Poly(vinyl Alcohol) Matrix Using Mechanical Alloying

Mechanical alloying was performed to obtain a composite material with a homogeneous dispersion of silver particles in a poly(vinyl alcohol) (PVA) matrix. Silver is a bactericidal material, and PVA is a widely used biocompatible polymer. Therefore, this mix can lead to a potentially functional biomaterial. This study focuses on the combination of both materials, processed by mechanical alloying, which has a promising application potential. The silver (Ag) used was ultrafine, measuring between 200 and 400 nanometers, produced from silver nitrate (AgNO3) redox. The Attritor high–energy, water–cooled ball mill was used to mill PVA for 4 h, at 600 rpm speed rotation and 38:1 power milling. Mechanical alloying was demonstrated to cause particle refinement in PVA with a timespan of 1 h. A slight additional particle decrease occurred for long–time milling. A milling time of 4 h was used to disperse the silver particles in the polymer matrix homogeneously. Hot pressing films were produced from the obtained dispersion powders. The microstructural features were studied using several material characterization techniques. Antimicrobial Susceptibility Tests (AST), conducted in an in–vitro assay, showed a hydrophilic character of the films and a protection against bacterial growth, making the process a promising path for the production of surface protective polymeric films

Detection of dopamine using glassy carbon electrodes modified with AgNPs synthetized with Monteverdia ilicifolia extract

This work reports a new application for a well-known medicinal plant used in Brazil. The green synthesis of silver nanoparticles (AgNPs) using the aqueous extract of Monteverdia ilicifolia (MI) leaves as stabilizing and reducing agent is described. The AgNPs-MI obtained were characterized by UV-VIS, FTIR, and Raman spectroscopies, DLS, zeta potential and FEG-SEM, which demonstrated that M. ilicifolia was effective at capping the AgNPs, yielding stable suspensions. These nanoparticles were deposited on glassy carbon electrodes, and they were efficiently applied as electrochemical sensors for the determination of dopamine (DA) using square wave voltammetry (SWV). The AgNPs-MI improved the electrochemical properties of the electrodes and enhanced their electroanalytical performance. The developed sensing device presented detection and quantification limits equal to 0.52 and 1.74 μmol L–1, respectively, towards DA determination. The proposed electrochemical sensor quantified this neurotransmitter successfully, confirming its potential as a new promising analytical detection tool for DA quality control

Chemical Composition and Biological Activities of The Essential Oil And Anatomical Markers Of Lavandula Dentata L. Cultivated In Brazil

ABSTRACT Lavandula dentata, popularly known as lavender, is commonly used in traditional medicine for the treatment of digestive and inflammatory disorders. The objective of this study was to analyzed the chemical oil composition, antioxidant and antimicrobial activities of the essential oil and anatomical markers of the leaf and stem of L. dentata cultivated in South Brazil. Essential oil showed an antioxidant activity similar to rutin and gallic acid when analyzed by phosphomolybdenum method. However, by the free radical DPPH and ABTS methods, it showed a slight potential antioxidant. Essential oil presented 1,8-cineol (63%) as major component, antimicrobial activity against Gram-positive, Gram-negative bacteria strains and Candida albicans, by broth microdilution. The anatomical profile provided the following main microscopic markers: hypostomatic leaves; diacytic stomata, thin and striate cuticle; multicellular and branched non-glandular trichomes; capitate glandular trichomes; peltate glandular trichomes; dorsiventral mesophyll; flat-convex shape midrib, truncated on the abaxial side; one collateral vascular bundle in the midrib; square stem shape, angular collenchyma alternated with cortical parenchyma; sclerenchymatic fibers well-developed on the four edges

Chemical composition and biological activity of Baccharis erioclada DC. essential oil

The chemically complex essential oils of Baccharis species are associated with several biological activities, such as antimicrobial and antiulcerous properties. However, few studies have investigated Baccharis erioclada DC. Therefore, in this study, we aimed to characterize the essential oil of B. erioclada and evaluate its antioxidant, antimicrobial, and hemolytic potential. The essential oil was extracted by hydrodistillation using a Clevenger apparatus and analyzed via gas chromatography-mass spectrometry (GC-MS). Phosphomolybdenum complex formation, reducing antioxidant power, and thiobarbituric acid reactive substances (TBARS) methods were used to determine antioxidant potential. To evaluate the essential oil’s antimicrobial activity, minimum inhibitory concentrations (MIC) in Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were calculated. Hemolytic activity was determined in sheep red blood cells. Thirty-one compounds were identified via GC-MS analysis, representing 81.60% of the total essential oil. These compounds included: turmerone (27.97%), fokienol (13.47%), ledol (9.78%), and santalol (5.35%). The class of compounds identified was the oxygenated sesquiterpenes (62.52%). Antioxidant activity was confirmed via phosphomolybdenum complex formation and TBARS methods. Moderate antimicrobial activity and low hemolysis rates were displayed at concentrations of 250 and 500 μg/mL