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1.
Compr Rev Food Sci Food Saf ; 19(4): 1680-1726, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33337087

RESUMEN

Natural phenolic compounds are abundant in the vegetable kingdom, occurring mainly as secondary metabolites in a wide variety of chemical structures. Around 10,000 different plant phenolic derivatives have been isolated and identified. This review provides an exhaustive overview concerning the electron transfer reactions in natural polyphenols, from the point of view of their in vitro antioxidant and/or pro-oxidant mode of action, as well as their identification in highly complex matrixes, for example, fruits, vegetables, wine, food supplements, relevant for food quality control, nutrition, and health research. The accurate assessment of polyphenols' redox behavior is essential, and the application of the electrochemical methods in routine quality control of natural products and foods, where the polyphenols antioxidant activity needs to be quantified in vitro, is of the utmost importance. The phenol moiety oxidation pathways and the effect of substituents and experimental conditions on their electrochemical behavior will be reviewed. The fundamental principles concerning the redox behavior of natural polyphenols, specifically flavonoids and other benzopyran derivatives, phenolic acids and ester derivatives, quinones, lignins, tannins, lignans, essential oils, stilbenes, curcuminoids, and chalcones, will be described. The final sections will focus on the electroanalysis of phenolic antioxidants in natural products and the electroanalytical evaluation of in vitro total antioxidant capacity.


Asunto(s)
Antioxidantes , Electroquímica , Polifenoles/química , Bebidas/análisis , Análisis de los Alimentos , Tecnología de Alimentos/métodos , Oxidación-Reducción , Polifenoles/análisis
2.
Ecotoxicol Environ Saf ; 179: 143-150, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31035248

RESUMEN

Doxorubicin (DOX) is an anthracycline widely used in treatments of several cancers, so it has found in hospital effluents with a significant concentration (above 1 µg L-1). Electrochemical remediation is an alternative to promote its degradation. The aim of this work was to evaluate the ability of nanostructured graphite electrodes with metallic oxides to degrade DOX by electro-oxidation (EO). Graphite, TiO2@graphite and AuO-TiO2@graphite electrodes were used in medium with tap water or 10 mmol L-1 NaCl. DOX treatments at concentrations of 1.25-5 mg L-1 were carried out in a voltage source with 1.5-5 V. The cathode used was the platinum electrode. The treatment of DOX 1.25 mg L-1 with 10 mmol L-1 NaCl electrolyte using the AuO-TiO2@graphite electrode at 5 V and 1 mA was the best methodology to promote its degradation. Also, the modified electrode was efficient to DOX degradation after 17 cycles of reuse. An energy expenditure of 1.11 and 0.2 kWh m-3 were obtained for 3 and 50 mL of treatment, respectively. Fish embryo acute toxicity test with zebrafish (Danio rerio) were performed before and after treatment by EO using NaCl. This treatment caused no effect on embryo-larval development, however it induced significant damage in the DNA of the zebrafish larvae after 96 h of exposure, which emphasizes the importance of a depth ecotoxicological evaluation during the development of EO methodologies.


Asunto(s)
Doxorrubicina/análisis , Técnicas Electroquímicas/métodos , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Animales , Doxorrubicina/toxicidad , Ecotoxicología , Electrodos , Electrólitos , Embrión no Mamífero/efectos de los fármacos , Grafito/química , Oxidación-Reducción , Titanio/química , Pruebas de Toxicidad Aguda , Aguas Residuales/química , Contaminantes Químicos del Agua/toxicidad , Pez Cebra
3.
Prep Biochem Biotechnol ; 49(4): 375-383, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30777480

RESUMEN

Laccase extract (LE) from Pycnoporus sanguineus was immobilized on calcium and copper alginate-chitosan beads and applied for the removal of 17α-ethinylestradiol (EE2). Effects of immobilization conditions such as: sodium alginate (SA) concentration; LE/SA ratio and chitosan/ion (Ca+2 or Cu+2) ratio on the immobilization yield were investigated. Immobilized LE on Ca-beads and Cu-beads was then used to degrade an EE2 solution. The optimal conditions for LE immobilization on Ca-beads were: 1.5% (w/v) SA, 1:5 (v/v) LE/SA and 3:7 (v/v) chitosan/ion (Ca+2). The optimal conditions for immobilization on Cu-beads were 2.0% (w/v) SA, 0.5:5 (v/v) LE/SA and 3:7 (v/v) chitosan/ion (Cu+2). The best result was obtained for immobilized LE on Ca-beads in buffer-absent medium. Furthermore, the immobilized enzyme was reused in five cycles for EE2 removal. The formation of EE2 dimers by LE treatment has been demonstrated by electrospray ionization coupled to time of flight mass spectrometer (ESI-TOF-MS). The results evidenced that immobilized LE in alginate-chitosan-divalent cation bead is an effective alternative for EE2 removal.


Asunto(s)
Alginatos/química , Quitosano/química , Restauración y Remediación Ambiental/métodos , Etinilestradiol/aislamiento & purificación , Lacasa/química , Administración de Residuos/métodos , Enzimas Inmovilizadas/química , Etinilestradiol/química , Porosidad , Pycnoporus/enzimología , Estereoisomerismo
4.
Molecules ; 21(8)2016 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-27529208

RESUMEN

The development of sensors and biosensors based on copper enzymes and/or copper oxides for phenol sensing is disclosed in this work. The electrochemical properties were studied by cyclic and differential pulse voltammetry using standard solutions of potassium ferrocyanide, phosphate/acetate buffers and representative natural phenols in a wide pH range (3.0 to 9.0). Among the natural phenols herein investigated, the highest sensitivity was observed for rutin, a powerful antioxidant widespread in functional foods and ubiquitous in the plant kingdom. The calibration curve for rutin performed at optimum pH (7.0) was linear in a broad concentration range, 1 to 120 µM (r = 0.99), showing detection limits of 0.4 µM. The optimized biomimetic sensor was also applied in total phenol determination in natural samples, exhibiting higher stability and sensitivity as well as distinct selectivity for antioxidant compounds.


Asunto(s)
Productos Biológicos/química , Biomimética , Técnicas Biosensibles , Fenoles/química , Antioxidantes/química , Antioxidantes/farmacología , Productos Biológicos/análisis , Biomimética/métodos , Técnicas Electroquímicas , Grafito/química , Fenoles/análisis
5.
Pak J Pharm Sci ; 29(2): 535-40, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27087097

RESUMEN

Eugenia dysenterica DC (cagaiteira) is a native tree from Cerrado biome. Cagaita fruits are known and consumed in natura, mainly by inhabitants from Cerrado. In this study, we evaluated the antioxidant activity of leaves of this plant. For this evaluation we used four methods, the reduction of phosphomolybdenum, scanning by hydrogen peroxide, DPPH radical scavenging assay and determination of electrochemical parameters by differential pulse voltammetry. The results indicate that all extracts from leaves of this species have significant antioxidant potential, following the order: crude ethanol extract CEE) >crude aqueous extract (CAE) >crude hexane extract (CHE). The voltammetric approaches were also applied in order to evaluate the redox behavior of the hydrophilic extracts, as well as of their sub-extracts. Thus, the results suggest the presence of catechol-like polyphenols, which were confirmed by chromatography and phytochemical methods. Voltammetric analysis showed to be a reliable and fast method to determine redox behavior of E. dysenterica extracts.


Asunto(s)
Antioxidantes/farmacología , Catecoles/farmacología , Eugenia/química , Extractos Vegetales/farmacología , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/química , Catecoles/aislamiento & purificación , Técnicas Electroquímicas , Etanol/química , Hexanos/química , Interacciones Hidrofóbicas e Hidrofílicas , Oxidación-Reducción , Fitoterapia , Picratos/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta , Plantas Medicinales , Solventes/química , Espectrofotometría , Agua/química
6.
Dent Mater ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39117498

RESUMEN

OBJECTIVE: This study aimed to investigate the effects of adding cholesteryl methacrylate (CM) monomer to experimental composite resins and evaluate its impact on polymerization shrinkage force (PSF), Knoop microhardness (KHN), sorption and solubility (SS), vulnerability to spontaneous oxidation (VOE), porosity (BES), viscosity (V), and cross-link density (CLD). CM was synthesized, mixed with varying proportions of Bis-GMA, 70 wt% filler particles, and 40 % TEGDMA. The groups tested were: CM0 (60 % Bis-GMA), CM6 (54 % Bis-GMA/6 % CM), CM12 (48 % Bis-GMA/12 % CM), CM18 (42 % Bis-GMA/18 % CM) and CM24 (36 % Bis-GMA/24 % CM). The PSF was evaluated using a universal testing machine. KHN was measured with a 50 g load for 30 s. SS was determined according to ISO 4049:2009. VOE was measured with a three-electrode system in an electrochemical cell. BES images were obtained using an electron microscope to assess porosity. Viscosity was measured through rheological analysis. CLD was estimated from hardness readings before and after ethanol storage. RESULTS: CM6 (0.34 N) and CM12 (0.34 N) exhibited the lowest PSF values compared to CM0 (0.91 N). For KHN, CM6 (32.03) and CM12 (31.03) had higher values than CM0 (25.83) and were similar to CM18 (29.39) and CM24 (28.64). SS showed no significant differences among the groups. VOE indicated low vulnerability across all groups. CM12 had greater porosity compared to CM0 in BES images. CM0 had the lowest viscosity among the groups. No differences in CLD were observed among CM0, CM12, CM18, and CM24 regarding softening effects. SIGNIFICANCE: Adding CM to Bis-GMA/TEGDMA composite resins can reduce polymerization shrinkage force and increase the initial Knoop microhardness without affecting the other properties studied.

7.
J Inorg Biochem ; 251: 112441, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38103419

RESUMEN

A prion-derived copper(II)-binding peptide was assembled onto a gold electrode for the building of a voltammetric biosensor for measuring the Cu2+ metal ion in biological samples. The chosen sequence was H-CVNITKQHTVTTTT-NH2, with an appended cysteine residue for binding to the gold surface as a self-assembled monolayer and a histidine residue as the anchorage point for copper(II) complexation. The biosensor showed a linear range of 10-7 to 10-6 M with an 8.0 × 10-8 M detection limit and a 1.0 × 10-7 M quantification limit, with good precision, trueness, and absence of matrix effect. The quantification of Cu2+ was performed in the presence of other transition metal ions, such as Zn2+, Cd2+, Fe2+, or Ni2+, which indicates the excellent selectivity of the biosensor. When the modified electrode was applied for measuring copper(II) in calcined coffee seeds, a difference in copper amount was observed between two Coffea arabica cultivars that were submitted to a treatment with a copper-based antifungal, showing the applicability of the biosensor in the agricultural field.


Asunto(s)
Técnicas Biosensibles , Cobre , Cobre/química , Café , Péptidos/química , Oro/química , Iones
8.
Anal Methods ; 16(2): 189-195, 2024 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-38098444

RESUMEN

Brazilian spotted fever (BSF) is a serious disease of medical importance due to its rapid evolution and high lethality. The effectiveness of the treatment mainly depends on the rapid diagnosis, which is currently performed by indirect immunofluorescence and PCR tests, which require high costs and laboratory structure. In order to propose an alternative methodology, we sought to develop an impedimetric immunosensor (IM) based on the immobilization of specific IgY antibodies for IgG anti Rickettsia rickettsii, using blood plasma from capybara (Hydrochoerus hydrochaeris), for characterization, validation and applications of the ready IM. IM selectivity was observed when comparing capybara reagent IgG (IgGcr) readings with non-reagent IgG (IgGnr). A reagent IgG calibration curve was obtained, from which the limits of detection (LOD) and quantification (LOQ) of 1.3 ng mL-1 and 4.4 ng mL-1 were calculated, respectively. The accuracy tests showed that different concentrations of IgGcr showed a maximum deviation of 20.0%, with CI between 90.00% and 95.00%. Intermediate precision tests showed a relative standard deviation of 2.09% for researcher 1 and 2.61% for researcher 2, and the F test showed no significant difference between the recovery values found between the two analysts, since Fcal 1.56 < 5.05 and P-value 0.48 > 0, 05. Therefore, an impedimetric immunosensor was developed to detect anti BSF IgG in capybara blood plasma, which greatly contributes to the improvement of diagnostic tests, cost reduction and ease of execution.


Asunto(s)
Técnicas Biosensibles , Fiebre Maculosa de las Montañas Rocosas , Animales , Fiebre Maculosa de las Montañas Rocosas/diagnóstico , Fiebre Maculosa de las Montañas Rocosas/microbiología , Inmunoensayo , Roedores/microbiología , Inmunoglobulina G
9.
Anal Methods ; 16(4): 645, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38205857

RESUMEN

Correction for 'An impedimetric immunosensor for diagnosis of Brazilian spotted fever in blood plasma' by Marx Osório Araújo Pereira et al., Anal. Methods, 2024, https://doi.org/10.1039/d3ay01308a.

10.
Dent Mater ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39112294

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the degree of conversion (%), flexural strength (MPa), elastic modulus (GPa), compressive strength (MPa), Knoop microhardness (KHN), post-gel shrinkage (%) and prediction of ideal concentration of cholesteryl methacrylate (CM) in experimental resins. METHODS: Four formulations were manipulated (F): F1, control group, (0 % CM); F2 (15 % CM); F3 (19.8 % CM) and F4 (30 % CM). Bis-GMA and CM percentages were determined using Statistica™ software. For the degree of conversion test, Raman spectroscopy was used. To testing flexural strength, elastic modulus and compressive strength, a universal testing machine was used. For the Knoop microhardness test five indentations were made in each sample. Post-gel shrinkage was determined using the strain gauge method. Statistica™ software processed all data obtained in this study. Results were submitted to one-way ANOVA and Tukey's post hoc tests (α = 0.05). RESULTS: Better performance was observed for F2 (15 % CM) and F3 (19,8 % CM) for degree of conversion, elastic modulus and post-gel shrinkage. For Knoop microhardness F2 (15 % CM), F3 (19,8 % CM) and F4 (30 % CM) showed higher values than F1 (0 % CM). For flexural strength F1 (0 % CM) and F3 (19,8 %) were similar and F4 showed the lowest values and for compressive strength F1 (0 % CM) showed the highest values. For mixture designs analysis data, concentrations ≤ 25 % of CM would provide better results. SIGNIFICANCE: Addition of CM at concentrations lower than 30 % contributed to a significant increase in the degree of conversion, microhardness values, elastic modulus and reduction of post-gel shrinkage.

11.
Pharmacol Rep ; 75(2): 276-292, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36719635

RESUMEN

BACKGROUND: L-proline transporter (PROT/SLC6A7) is closely associated with glutamatergic neurotransmission, where L-proline modulates the NMDA receptor (NMDAR) function. NMDAR-mediated excitotoxicity is a primary cause of neuronal death following stroke, which is triggered by the uncontrolled release of glutamate during the ischemic process. After ischemic stroke, L-proline levels show a reduction in the plasma, but high circulating levels of this molecule indicate good functional recovery. This work aimed to produce new PROT inhibitors and explore their effects on ischemic stroke. METHODS: Initially, we built a three-dimensional model of the PROT protein and run a molecular docking with the newly designed compounds (LQFM215, LQFM216, and LQFM217). Then, we synthesized new PROT inhibitors by molecular hybridization, and proline uptake was measured in ex vivo and in vivo models. The behavioral characterization of the treated mice was performed by the open-field test, elevated plus-maze, Y-maze, and forced swimming test. We used the permanent middle cerebral artery occlusion (MCAO) model to study the ischemic stroke damage and analyzed the motor impairment with limb clasping or cylinder tests. RESULTS: LQFM215 inhibited proline uptake in hippocampal synaptosomes, and the LQFM215 treatment reduced proline levels in the mouse hippocampus. LQFM215 reduced the locomotor and exploratory activity in mice and did not show any anxiety-related or working memory impairments. In the MCAO model, LQFM215 pre-treatment and treatment reduced the infarcted area and reduced motor impairments in the cylinder test and limb clasping. CONCLUSIONS: This dataset suggests that the new compounds inhibit cerebral L-proline uptake and that LQFM215 promotes neuroprotection and neuro-repair in the acute ischemic stroke model.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Ratones , Animales , Accidente Cerebrovascular Isquémico/complicaciones , Neuroprotección , Simulación del Acoplamiento Molecular , Infarto de la Arteria Cerebral Media/complicaciones , Receptores de N-Metil-D-Aspartato , Prolina/farmacología , Isquemia Encefálica/complicaciones , Modelos Animales de Enfermedad
12.
Prev Nutr Food Sci ; 26(4): 417-424, 2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35047438

RESUMEN

Grapes and their derivatives have antioxidant and cardioprotective properties. Therefore, we hypothesized that grape juice (GJ) could improve vascular oxidative damage caused by chlorine radicals (OCl-), which are excessively produced in vascular tissue during cardiovascular diseases (mainly diabetes and hypertension). The antioxidant capacity of GJ was analyzed by an electrochemical method, followed by administration in rats (100 or 300 mg/kg/d, via the oral) for seven days. Then, rats were sacrificed, and their aortas were isolated and subjected to isometric recordings or immuno-histochemical analyses with or without exposure to OCl- (5, 20, or 100 µM, 60 min). Concentration-effect curves for acetylcholine (ACh) and sodium nitroprusside (SNP) were derived to analyze endothelium-dependent or independent vasore-laxation. The GJ presented with high antioxidant capacity, and treatment with GJ did not alter vascular relaxation induced by ACh or SNP. After exposure to OCl-, endothelium-denuded arteries showed preserved relaxation with SNP, whereas endothelium-intact arteries showed reduced relaxation with ACh. OCl- at various concentrations induced significantly decreased relaxation of arteries (80.6±4.2%, 55.4±4.7%, and 28.1±5.9%, respectively) vs. control arteries (96.8±2.4%). However, treatment with GJ prevented loss in relaxation caused by 5 and 20 µM OCl- and improved relaxation after exposure to 100 µM OCl-. Exposure to OCl- induced increased nitrotyrosine immunostaining of endothelial cell layers, which was improved by GJ treatment. Altogether, vascular damage caused by OCl- was prevented by treatment with GJ, and GJ prevented nitrosative stress in these vessels.

13.
Anticancer Agents Med Chem ; 20(14): 1688-1694, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32329702

RESUMEN

BACKGROUND: The strategic development of therapeutic agents, capable of being targeted at their active sites, has been a major goal in treatment of cancer. The delivery of drugs for tumors has as its main challenge the development of safe and effective drugs, since the goal of chemotherapy is to eliminate the tumor completely without affecting healthy cells. The aim of present study was to investigate the antioxidant, anticancer activities of zidovudine and its α-O-glycosylated derivative obtained by biosynthesis of a filamentous fungi, Cunninghamela echinulata. METHODS: An evaluation of the cytotoxic potential of zidovudine and its α-O-glycosylated was performed in fibroblasts and melanoma cells by the tetrazolium reduction method (MTT) and the antioxidant activity of this derivative was observed. RESULTS: The antioxidant activity of zidovudine demonstrated an electrochemical oxidation potential of 0.91V, while the α-O-glycosylated derivative did not exhibit any antioxidant activity. The zidovudine exhibited low cytotoxicity for melanoma and fibroblast cells, while the α-O-glycosylated derivative presented better cytotoxicity on melanoma cells at a concentration of 10mg. mL-1. CONCLUSION: This study demonstrates the specific cytotoxicity of the glycoconjugate and suggests that glycosylation by biosynthesis can be a useful strategy for obtaining new anticancer compounds.


Asunto(s)
Antineoplásicos/farmacología , Cunninghamella/metabolismo , Zidovudina/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Glicosilación , Ratones , Estructura Molecular , Oxidación-Reducción , Relación Estructura-Actividad , Células Tumorales Cultivadas , Zidovudina/química , Zidovudina/metabolismo
14.
Pharmaceuticals (Basel) ; 12(2)2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-31167398

RESUMEN

Diclofenac (DIC) is a non-steroidal anti-inflammatory drug of wide use around the world. Electroanalytical methods display a high analytical potential for application in pharmaceutical samples but the drawbacks concerning electrode fouling and reproducibility are of major concern. Henceforth, the aim of this work was to propose the use of alternative low-cost carbon black (CB) and ionic liquid (IL) matrix to modify the surface of pencil graphite electrodes (PGE) in order to quantify DIC in raw materials, intermediates, and final products, as well as in stability assays of tablets. The proposed method using CB+IL/PGE displayed good recovery (99.4%) as well as limits of detection (LOD) of 0.08 µmol L-1 and limits of quantification (LOQ) of 0.28 µmol L-1. CB+IL/PGE response was five times greater than the unmodified PGE. CB+IL-PGE stands as an interesting alternative for DIC assessment in different pharmaceutical samples.

15.
Pharmaceuticals (Basel) ; 12(3)2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31374819

RESUMEN

This work details the study of the redox behavior of the drugs cyclobenzaprine (CBP), amitriptyline (AMP) and nortriptyline (NOR) through voltammetric methods and computational chemistry. Results obtained in this study show that the amine moiety of each compound is more likely to undergo oxidation at 1a at Ep1a ≈ 0.69, 0.79, 0.93 V (vs. Ag/AgCl/KClsat) for CBP, AMP and NOR, respectively. Moreover, CBP presented a second peak, 2a at Ep2a ≈ 0.98 V (vs. Ag/AgCl/KClsat) at pH 7.0. Furthermore, the electronic structure calculation results corroborate the electrochemical assays regarding the HOMO energies of the lowest energy conformers of each molecule. The mechanism for each anodic process is proposed according to electroanalytical and computational chemistry findings, which show evidence that the methods herein employed may be a valuable alternative to study the redox behavior of structurally similar drugs.

16.
Pharmaceuticals (Basel) ; 11(4)2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-30301183

RESUMEN

Methyldopa is a catecholamine widely used in the treatment of mild to moderate hypertension whose determination in pharmaceutical formulae is of upmost importance for dose precision. Henceforth, a low-cost carbon paste electrode (CPE) consisting of graphite powder obtained from a crushed pencil stick was herein modified with nanostructured TiO2 (TiO2@CPE) aiming for the detection of methyldopa in pharmaceutical samples. The TiO2-modified graphite powder was characterized by scanning electron microscopy and X-ray diffraction, which demonstrated the oxide nanostructured morphology. Results evidenced that sensitivity was nonetheless increased due to electro-catalytic effects promoted by metal modification, and linear response obtained by differential pulse voltammetry for the determination of methyldopa (pH = 5.0) was between 10⁻180 µmol/L (Limit of Detection = 1 µmol/L) with the TiO2@CPE sensor. Furthermore, the constructed sensor was successfully applied in the detection of methyldopa in pharmaceutical formulations and excipients promoted no interference, that indicates that the sensor herein developed is a cheap, reliable, and useful strategy to detect methyldopa in pharmaceutical samples, and may also be applicable in determinations of similar compounds.

17.
Oxid Med Cell Longev ; 2018: 3250908, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30327710

RESUMEN

Eugenia dysenterica ex DC Mart. (Myrtaceae), popularly known as "cagaita," is a Brazilian plant rich in polyphenols and other antioxidant compounds. Aiming to evaluate the potential use of cagaita in pathologies involving oxidative stress, such as neurodegenerative disorders, this study investigated its antioxidant potential and neuroprotective effect. Electrochemical approaches and aluminium-induced neurotoxicity were used to determine respectively in vitro and in vivo antioxidant properties of cagaita. Voltammetric experiments were carried out in a three-electrode system, whose working electrode consisted of glassy carbon. Male Swiss mice were administered with AlCl3 orally at a dose of 100 mg/kg/day and with cagaita leaf hydroalcoholic extract (CHE) at doses of 10, 100, and 300 mg/kg/day. The redox behavior of CHE presented similar features to that of quercetin, a widely known antioxidant standard. CHE prevented mouse memory impairment which resulted from aluminium intake. In addition, biochemical markers of oxidative stress (catalase, superoxide dismutase activity, and lipid peroxidation) were normalized by CHE treatment. The potential of CHE to prevent aluminium-induced neurotoxicity was reflected at the microscopic level, through the decrease of the number of eosinophilic necrosis phenotypes seen in treated groups. Moreover, the protective effect of CHE was similar to that of quercetin, which was taken as the standard. These findings showed that the CHE of cagaita leaves has a potential to protect the brain against oxidative-induced brain damage.


Asunto(s)
Antioxidantes/farmacología , Encéfalo/efectos de los fármacos , Eugenia , Fármacos Neuroprotectores/farmacología , Extractos Vegetales/farmacología , Cloruro de Aluminio/toxicidad , Animales , Encéfalo/patología , Eugenia/química , Masculino , Ratones , Neuroprotección/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Hojas de la Planta/química
18.
Chem Biol Interact ; 291: 162-170, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29920285

RESUMEN

Amoxicillin (AMX) is one of the most commonly prescribed antibiotics around the world to treat and prevent several diseases in both human and veterinary medicine. Incomplete removal of AMX during wastewater treatment contributes to its presence in water bodies and drinking water. AMX is an emerging contaminant since its impact on the environment and human health remains uncertain. This contribution was aimed to evaluate the electrochemical oxidation (EO) of AMX using different anodes in tap water, NaCl or Na2SO4 solutions and to evaluate the potential toxicity of remaining AMX and its by-products on zebrafish early-life stages. Chemical intermediates generated after EO were determined by mass spectrometry and their resulting antimicrobial activity was evaluated. AMX did not induce significant mortality in zebrafish during extended exposure but affected zebrafish development (increased body length) from 6.25 mg/L to 25 mg/L and inhibited enzymatic biomarkers. Carbon modified with titanium oxide (TiO2@C) anode achieved complete AMX removal in just a few minutes and efficiency of the supported electrolytes occurred in the following order: 0.1 M NaCl > 0.1 M Na2SO4 > 0.01 M NaCl > tap water. The order of potential toxicity to zebrafish early life-stages related to lethal and sublethal effects was as follows: 0.1 M Na2SO4 > 0.1 M NaCl >0.01 M NaCl = tap water. Additionally, the EO of AMX using TiO2@C electrode with 0.01 M NaCl was able to inhibit the antimicrobial activity of AMX, reducing the possibility of developing bacterial resistance.


Asunto(s)
Amoxicilina/farmacocinética , Antiinfecciosos/farmacocinética , Electroquímica , Amoxicilina/toxicidad , Animales , Catalasa/metabolismo , Embrión no Mamífero/efectos de los fármacos , Femenino , Glutatión Transferasa/metabolismo , Concentración de Iones de Hidrógeno , Inactivación Metabólica , L-Lactato Deshidrogenasa/metabolismo , Masculino , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Soluciones , Análisis de Supervivencia , Temperatura , Pruebas de Toxicidad Aguda , Pez Cebra/embriología
19.
Oxid Med Cell Longev ; 2018: 9842908, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30420910

RESUMEN

Pequi (Caryocar brasiliense) is an endemic species from Brazilian Cerrado, and their fruits are widely used in regional cuisine. In this work, a crude hydroalcoholic extract (CHE) of C. brasiliense leaves and its resulting fractions in hexane (HF), chloroform (CF), ethyl acetate (EAF), and butanol (BF) were investigated for their antioxidant properties and anticholinesterase activities. The antioxidant properties were evaluated by free radical scavenging and electroanalytical assays, which were further correlated with the total phenolic content and LC-MS results. The acetylcholinesterase and butyrylcholinesterase inhibitory activities were examined using Ellman's colorimetric method. The LC-MS analysis of EAF revealed the presence of gallic acid and quercetin. CHE and its fractions, EAF and BF, showed anticholinesterase and antioxidant activities, suggesting the association of both effects with the phenolic content. In addition, behavioral tests performed with CHE (10, 100, and 300 mg/kg) showed that it prevented mice memory impairment which resulted from aluminium intake. Moreover, CHE inhibited brain lipid peroxidation and acetyl and butyryl-cholinesterase activities and the extract's neuroprotective effect was reflected at the microscopic level. Therefore, the leaves of pequi are a potential source of phenolic antioxidants and can be potentially used in treatments of memory dysfunctions, such as those associated with neurodegenerative disorders.


Asunto(s)
Antioxidantes/farmacología , Inhibidores de la Colinesterasa/farmacología , Ericales/química , Fármacos Neuroprotectores/farmacología , Hojas de la Planta/química , Acetilcolinesterasa/metabolismo , Animales , Conducta Animal , Butirilcolinesterasa/metabolismo , Corteza Cerebral/patología , Electroquímica , Etanol/química , Ácido Gálico/análisis , Concentración 50 Inhibidora , Masculino , Malondialdehído/metabolismo , Ratones , Fenoles/análisis , Extractos Vegetales/farmacología , Quercetina/análisis , Estándares de Referencia , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Agua/química
20.
Food Chem ; 217: 326-331, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27664641

RESUMEN

Red fruits are rich sources of antioxidant compounds with recognized health benefits. Since they are perishable, dried extracts emerge as more durable products and their quality control must include antioxidant capacity assays. In this study, the redox behavior of commercial dried products obtained from camu-camu, açai, acerola and cranberry red fruits was evaluated by electroanalytical approaches. The antioxidant potential was determined by 2,2-diphenyl-1-picrylhydrazyl free radical assay and the electrochemical index concept. The total phenol content was estimated by using a laccase based biosensor. A significant correlation was found between all methods and literature data. The voltammetric profile (cyclic, differential and square wave) obtained for each type of dried extract showed distinguishable features that were correlated with their main major markers, being also useful for identification purposes. The electrochemical methods were cheaper and more practical for evaluation of antioxidant properties and total phenol content in dried powders obtained from different red fruits.


Asunto(s)
Antioxidantes/análisis , Frutas/química , Compuestos de Bifenilo/análisis , Fenoles/análisis , Picratos/análisis , Extractos Vegetales/análisis , Vaccinium macrocarpon/química
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