Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
J Toxicol Environ Health A ; 86(21): 816-832, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37667472

RESUMO

The particular plant species found in southern Brazil, Vassobia breviflora (Solanaceae) has only a few apparent studies examining its biological effect. Thus, the aim of the present study was to determine the activity of the acetone extract fraction derived from V. breviflora. Four compounds were identified by ESI-qTOF-MS: eucalrobusone R, aplanoic acid B, pheophorbide A, and pheophytin A. In addition, 5 compounds were identified by HPLC-PDA-MS/MS: all-trans-lutein, 15-cis-lutein, all-trans-ß-carotene, 5,8-epoxy-ß-carotene, and cis-ß-carotene. Cell lines A549 (lung cancer), A375 (melanoma cancer) and HeLa (cervical cancer) were incubated with different concentrations of each studied extract using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and 2'-7'dichlorofluorescin diacetate (DCFH-DA) assays. The acetonic extract exhibited cytotoxic activity at a concentration of 0.03 mg/ml in the HeLa strain and 0.1 mg/ml in the others. In addition to increased production of reactive oxygen species (ROS). Antibacterial activity was assessed utilizing minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) in 9 ATCCs strains and 7 clinical isolates, as well as determination of biofilm production. Data demonstrated that MIC and MBC were approximately 256 mg/ml in most of the strains tested and antibiofilm effect at S. aureus, S. epidermidis, A. baumannii, and E. faecalis, concentrations below the MIC. Genotoxic activity on plasmid DNA did not produce significant elevated levels in breaks in the isolated genetic material.


Assuntos
Acetona , Luteína , Staphylococcus aureus , Espectrometria de Massas em Tandem , beta Caroteno , Brasil
2.
J Toxicol Environ Health A ; 86(2-3): 51-68, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36543759

RESUMO

Vassobia breviflora (Sendtn.) Hunz is a plant of the Solanaceae family from South America and there are no apparent studies reported on the biological activity of the hexane extract. The aim of this investigation was to conduct phytochemical analyses using ESI-TOF-MS, while antioxidant activities were evaluated by the following methods 1,1-diphenyl-2-picrylhydrazyl (DPPH) 2,2"-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical capture (ABTS), ferric reducing antioxidant power (FRAP), total antioxidant capacity (TAC), and total oxidant status (TOS). Antimicrobial activities were performed by determining the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antibiofilm formed. Cytotoxicity was measured by MTT and dsDNA PicoGreen tests, beyond the production of reactive oxygen species (ROS) determined by Dichlorodihydrofluorescein diacetate (DCFH-DA). The hexane extract showed the presence of 5 (choline, pantothenic acid, calystegine B, lanciphodylactone I, and 15"-cis-zeaxanthin) compounds detected. V. breviflora extract demonstrated reliable results utilizing different antioxidant methods. In antibacterial activity, V. breviflora extract exhibited inhibitory, bactericidal, and antibiofilm action in biofilm-forming bacteria. The hexane extract exhibited cytotoxicity against melanoma, lung cancer, glioblastoma, leukemia, uterine colon, and hepatocarcinoma tumor cells. In addition, all tested strains resulted in increased production of ROS. This plant extract may be considered in future as an alternative for development of new therapeutic options aimed at the treatment of diverse pathologies.


Assuntos
Antioxidantes , Solanaceae , Antioxidantes/farmacologia , Antioxidantes/química , Espécies Reativas de Oxigênio , Hexanos , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia
3.
J Toxicol Environ Health A ; 85(23): 972-987, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36208226

RESUMO

Cancer and infectious diseases are among the leading causes of death in the world. Despite the diverse array of treatments available, challenges posed by resistance, side effects, high costs, and inaccessibility persist. In the Solanaceae plant family, few studies with Vassobia breviflora species relating to biological activity are known, but promising results have emerged. The phytochemicals present in the ethyl acetate fraction were obtained using ESI-MS-QTOF, and the antioxidants assays 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical capture (ABTS), plasma ferric reduction capacity (FRAP), and total antioxidant capacity (TAC). Cytotoxic activity was evaluated by MTT, Neutral Red, and lactate dehydrogenase (LDH) released. The production of reactive oxygen species, nitric oxide, and purinergic enzymes was also investigated. Antibacterial activity was measured through minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antibiofilm activity, in addition to genotoxicity in plasmid DNA. Five major masses were identified D-glucopyranose II, allyl disulfide, γ-lactones, pharbilignoside, and one mass was not identified. V. breviflora exhibited relevant antioxidant and cytotoxic activity against the HeLa cell line and enhanced expression effect in modulation of purinergic signaling. Antibacterial activities in the assays in 7 ATCC strains and 8 multidrug-resistant clinical isolates were found. V. breviflora blocked biofilm formation in producing bacteria at the highest concentrations tested. However, there was no plasmid DNA cleavage at the concentrations tested. Data demonstrated that V. breviflora exhibited an antioxidant effect through several methods and proved to be a promising therapeutic alternative for use against tumor cells via purinergic signaling and multidrug-resistant microorganisms, presenting an anti-biofilm effect.


Assuntos
Antioxidantes , Solanaceae , Acetatos , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias , DNA/farmacologia , Células HeLa , Humanos , Lactato Desidrogenases , Lactonas/farmacologia , Testes de Sensibilidade Microbiana , Vermelho Neutro/farmacologia , Óxido Nítrico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio , Ácidos Sulfônicos
4.
Ultrason Sonochem ; 88: 106101, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35909035
5.
Food Res Int ; 125: 108645, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554039

RESUMO

The aim of this study was to develop and evaluate the physicochemical and antioxidant stability of nanoemulsions containing a Physalis peruviana calyx extract (CPp-NE) and free extracts under different storage conditions (7 and 25 °C) and with absence or incidence of light for 120 days. The calyx extracts were prepared with ethanol 60% and characterized for later preparation of the nanoemulsions by spontaneous emulsification. The formulations presented nanometric sizes, low polydispersity index, negative zeta potential, acid pH, rutin content (11 µg·mL-1), and encapsulation efficiency of 85%. Regarding the stability, the droplet size and PdI of the CPp-NE stored at refrigeration temperature in the dark, room temperature in the dark, and refrigeration temperature with light incidence were stable for 120 days and with no visible changes in the formulations. The antioxidant capacity was related to the reducing capacity, and the best results were found for nanoemulsions stored at room temperature and in absence of light. In addition, CPp-NE presented higher antioxidant and reducing capacity in relation to the free extracts.


Assuntos
Antioxidantes/química , Emulsões/síntese química , Flores/química , Nanopartículas/química , Physalis/química , Extratos Vegetais/química , Antioxidantes/análise , Fenômenos Químicos , Estabilidade de Medicamentos , Emulsões/química , Microscopia Eletrônica de Varredura , Rutina/análise
6.
Food Res Int ; 125: 108577, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554127

RESUMO

Lactobacillus acidophilus were encapsulated by complex coacervation followed by transglutaminase crosslinking, aiming to improve the resistance of the microcapsules and improve the protection for probiotics. Subsequently, microcapsules were dried by freeze drying. The encapsulation efficiency, morphology, thermal resistance, gastrointestinal simulation and storage stability were analysed for wet and dry forms. The treatments offered high encapsulation efficiency (68.20-97.72%). Transglutaminase maintained the structure rounded, multinucleate and homogeneous distribution of probiotics in the microcapsules. In relation to the thermal resistance, in general, microencapsulation was effective in protecting and crosslinked microcapsules demonstrated greater protection for probiotics, obtaining viable cell counts of up to 10 log CFU g-1, approximately. On exposure to the simulated gastrointestinal tract, microencapsulation coupled to crosslinking demonstrated good results and the dry form was more efficient in the protection and the treatment with greater amount of transglutaminase was highlighted (9.07 log CFU g-1). As for storage, probiotic viability was maintained for up to 60 days in freezing temperature, with counts of up to 9.59 log CFU g-1. The results obtained in the present work are innovative and present a promising alternative for the protection of probiotics and their addition in food products.


Assuntos
Células Imobilizadas/microbiologia , Lactobacillus acidophilus/enzimologia , Viabilidade Microbiana , Probióticos , Cápsulas/química , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Armazenamento de Alimentos , Liofilização , Trato Gastrointestinal/metabolismo , Modelos Biológicos , Transglutaminases/metabolismo
7.
Int J Food Microbiol ; 301: 27-33, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31082697

RESUMO

Pre-chilling leads to a temperature decline of the pre-rigor muscle of poultry carcasses, and a reduction of the initial bacterial load may occur. Both ultrasound (US) and slightly acidic electrolyzed water (SAEW) have been used alone in the meat industry for the manufacture of emulsions, pasteurization, and prevention of bacteria growth. However, the impact of the combination of these technologies during the pre-chilling of chicken carcasses has not been evaluated. In this study, breast chicken cylinders (CBCs) were pre-chilled for 10 min at 10 °C using SAEW and different US frequencies (25 and 130 kHz). The microbiological characteristics, lipid and protein oxidation, shear force, and anaerobic glycolysis were evaluated. The US + SAEW combination led to an effective reduction (P < 0.05) of enterobacteria, mesophilic bacteria, lactic acid bacteria, and psychrotrophic bacteria, while the lipid and protein oxidation, shear force, anaerobic glycolysis, and muscle structure were not affected (P > 0.05). Therefore, the combination of these technologies may be promising in the pre-chilling stage of chicken carcasses.


Assuntos
Ácidos/farmacologia , Carga Bacteriana/efeitos dos fármacos , Microbiologia de Alimentos/métodos , Carne/microbiologia , Ultrassom/normas , Animais , Galinhas/microbiologia , Temperatura Baixa , Eletrólise , Água/química
8.
Rev. colomb. ciencias quim. farm ; 48(1): 145-158, jan.-abr. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1042804

RESUMO

SUMMARY Cadmium (Cd2+) is a nonessential heavy metal that possesses a high capacity of bioaccumulation and exhibits toxic characteristics even at low concentrations. This study evaluated the genotoxicity and cytotoxicity in human leukocytes in vitro after exposure to a lower range of Cd2+concentration (1-25 (g/mL) using an unprecedented strategy by correlating between intracellular Cd2+ levels after exposure and cellular damage. Results demonstrated that Cd2+exposure from 5 to 25 fig/mL significantly increased the unviability of leukocytes, as well as the DNA damage, which was dose-dependent. The intracellular Cd2+ levels in leukocytes ranged from 9.85 to 94.38 pg/cell, and cytotoxicity and genotoxicity were induced at a concentration of24.22 pg/cell. The relationship between exposure concentration and intra-cellular Cd2+ levels suggests that its influx occurs in human leukocytes under zero-order kinetics.


RESUMEN El cadmio (Cd2+) es un metal pesado no esencial que posee una alta capacidad de bioacumulación y presenta características tóxicas incluso en bajas concentraciones. Este estudio evaluó la genotoxicidad y la citotoxicidad en leucocitos humanos in vitro después de la exposición a un rango inferior de concentración de Cd2+ (1-25 (g / mL) mediante una estrategia sin precedentes al correlacionar los niveles intracelulares de Cd2+ después de la exposición y el daño celular. Los resultados demostraron que la exposición a Cd2+ de 5 a 25 (g/mL aumentó significativamente la inviabilidad de los leucocitos, así como el daño en el ADN, que era dependiente de la dosis. Los niveles intracelulares de Cd2+ en leucocitos oscilaron entre 9,85 y 94,38 pg/célula, y se indujo la citotoxicidad y la genotoxicidad a una concentración de 24,22 pg/ célula. La relación entre la concentración de la exposición y los niveles intracelulares de Cd2+ sugiere que su influjo se produce en leucocitos humanos bajo una cinética de orden cero.

9.
Anal Chim Acta ; 1060: 45-52, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-30902330

RESUMO

An effective analytical method for bromine and iodine determination in human hair using interference-free inductively coupled plasma mass spectrometry (ICP-MS) was developed. Human hair was digested based on combustion reaction to obtain compatible solutions with ICP-MS analysis. Using microwave-induced combustion (MIC), masses of human hair ranging from 50 to 300 mg were efficiently digested. Only a diluted alkaline solution (100 mmol L-1 NH4OH) was used for the absorption of both analytes, which was fully compatible with ICP-MS analysis. Using these conditions low limits of detection were obtained (LOD of 0.01 µg g-1 for Br and 0.004 µg g-1 for I). Recovery tests at two levels (50% and 100%) using a standard solution or mixtures of the sample with certified reference materials (CRMs) were carried out to evaluate the suitability of proposed method and recoveries between 94% and 102% were always obtained. Accuracy was evaluated by analysis of a human hair CRM, and the Br and I concentrations obtained by the proposed method did not differ significantly from those described in the certificate. Repeatability (RSDs ≤ 4%) and reproducibility (RSDs ≤ 7%) of the results using proposed method were always very suitable. The digests obtained using the MIC method were fully compatible with ICP-MS and the interferences currently found using conventional digestion methods were completely eliminated. Ultra-trace concentrations of Br and I were determined in human hair, demonstrating that the proposed method is a suitable strategy, and it presents several advantages compared to others published in the literature.


Assuntos
Bromo/análise , Cabelo/química , Iodo/análise , Humanos , Espectrometria de Massas , Micro-Ondas
10.
Leuk Res ; 76: 11-14, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30472478

RESUMO

In this work, we investigated the stability of arsenic trioxide (ATO) used in leukemia treatment, encapsulated with nanoliposome, with the aid of ultrasound treatment. Stability studies of As species were followed by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS), allowing for the detection of the conversion of low amounts of As(III) to As(V) or the formation of other As species. The influence of storage temperature and time on ATO was evaluated. Low amounts of As(III) to As(V) conversions were observed when the As encapsulated with nanoliposome was incubated at 25 °C and 40 °C. However, As(III) was stable if the solution was maintained at 5 °C, even after 90 days. No formation of other As species was observed, indicating good stability of the encapsulated ATO. Next step of the work will focus on spray drying of ATO nanoliposomes-encapsuleted with the aim of long term stability of As.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/química , Trióxido de Arsênio/administração & dosagem , Trióxido de Arsênio/química , Antineoplásicos/farmacologia , Trióxido de Arsênio/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida , Estabilidade de Medicamentos , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Lipossomos , Espectrometria de Massas
11.
Biol Trace Elem Res ; 156(1-3): 130-3, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24078327

RESUMO

The aim of the present study was to evaluate the metabolism of organic chromium and its effect on digestibility and intake of lambs. Four 4-month-old male lambs, each weighing 28 kg, were used. The animals were kept in metabolic cages for a period of 20 days (15 days of adaptation and 5 days of experimentation), in two experimental phases, with inverted treatments. Organic chromium was administered by intraruminal infusion of 1 mg of chromium-rich yeast (Saccharomyces cerevisiae) throughout the adaptive and experimental period. The dry material rates of the diet and feces of the animals were evaluated to estimate consumption, digestibility, and fecal production. During the experimental period, blood, feces, and urine were collected every 24 h to determine chromium levels. There was no significant difference in the excretion of chromium in the urine, and no mineral remnants were detected in the blood. Excretion was generally fecal. There was greater excretion of chromium in the feces of lambs in the treated group on day 0 and day 3, compared with the control group. The use of organic chromium promoted an increase in the consumption of dry material in the treated animals only at day 0 (P <0.05). The production of fecal dry matter was greater among the treated lambs than among the animals of the control group on day 1, day 2, day 3, and day 4 (P <0.05). The results obtained showed that organic chromium associated with live yeasts is not absorbed by the body and do not affect the intake time in the dose used.


Assuntos
Cromo/metabolismo , Cromo/farmacologia , Suplementos Nutricionais , Saccharomyces cerevisiae , Animais , Feminino , Masculino , Ovinos
12.
J Nutr Metab ; 2013: 653185, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23840948

RESUMO

Background. This study investigates the effects of Brazil nut ingestion on serum lipid profile in healthy volunteers. Methods. Ten healthy subjects were enrolled in the study. Each subject was tested 4 times in a randomized crossover in relation to the ingestion of different serving sizes of the Brazil nut: 0, 5, 20, or 50 g. At each treatment point, peripheral blood was drawn before and at 1, 3, 6, 9, 24, and 48 hours and 5 and 30 days. Blood samples were tested for total cholesterol, high- and low-density lipoprotein cholesterol (HDL-c and LDL-c, resp.), triglycerides, selenium, aspartate and alanine aminotransferases, albumin, total protein, alkaline phosphatase, gamma GT, urea, creatinine, and C-reactive protein. Results. A significant increase of the plasma selenium levels was observed at 6 hours within the groups receiving the nuts. Serum LDL-c was significantly lower, whereas HDL-c was significantly higher 9 hours after the ingestion of 20 or 50 g of nuts. The biochemical parameters of liver and kidney function were not modified by ingestion of nuts. Conclusions. This study shows that the ingestion of a single serving of Brazil nut can acutely improve the serum lipid profile of healthy volunteers.

13.
Anal Methods ; 3(2): 288-293, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32938026

RESUMO

In this work, a method for chlorine determination in heavy crude oil using pyrohydrolysis for sample decomposition was developed. Chlorine was determined using ion chromatography (IC), inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry. In this case an ICP-MS spectrometer equipped with a dynamic reaction cell (DRC-ICP-MS) was used. Heavy crude oil samples were homogenized and placed on a quartz holder, which was then introduced into the pyrohydrolysis apparatus. Nitric acid (0.2 mL) was used to assist the decomposition of the sample. Solutions with different concentrations of ammonium hydroxide were evaluated to collect the volatile chloride produced using pyrohydrolysis. A 0.75 mol L-1 ammonium hydroxide solution was chosen in view of the better accuracy achieved. Best precision and accuracy were obtained by heating the sample for 10 min up to 1000 °C. The limits of quantification (LOQs, 10σ) of chlorine measured by IC, ICP OES and DRC-ICP-MS were 4.5, 48 and 3.6 µg g-1, respectively. A sample amount of 300 mg and final volume of 20 mL were taken into account to calculate the LOQs. The relative standard deviation (RSD) was lower than 5% (4 replicates). Accuracy was evaluated by analysis of certified reference material (NIST 1634c) and comparison with the results obtained using the ASTM D6470 method. In both cases the results obtained using pyrohydrolysis were in agreement. The proposed method was suitable for heavy crude oil decomposition and chlorine determination by IC, ICP OES and DRC-ICP-MS. Three samples per hour can be processed using a simple and low-cost pyrohydrolysis apparatus. The pyrohydrolysis procedure is easy to perform, which is very attractive for routine analysis of crude oil, a very complex matrix. According to the authors' knowledge this is the first application of pyrohydrolysis for heavy crude oil sample preparation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA