Doutorado em Inovação Farmacêutica em Rede (FF)
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Navegando Doutorado em Inovação Farmacêutica em Rede (FF) por Por Orientador "Gil, Eric de Souza"
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Item Desenvolvimento de métodos eletroanalíticos para avaliação da capacidade antioxidante(Universidade Federal de Goiás, 2016-03-28) Benjamin, Stephen Rathinaraj; Gil, Eric de Souza; http://lattes.cnpq.br/3218622824233303; Gil, Eric de Souza; Marreto, Ricardo Neves; Ghedini, Paulo César; Colmati Junior, Flavio; Oliveira, Severino Carlos Bezerra deThis study investigated the antioxidant activity using biosensors based on carbon paste electrode (CPE) modified with crude extract of laccase (Pycnoporus sanguineus, activity 2019 U L-1) in different compositions. The biosensor consists of carbon nanotubes activated with DNA (CPEL-DNA: CN) showed the best sensitivity level, 0.0549 μA / μM and 1.2 uM detection limit (LOD) in the concentration range of 20-140 μM of rutin. This biosensor showed excellent stability over 10 days and reproducibility (RSD <5%). This biosensor was used to determine the total amount of phenol in coffee samples (expressed by the equivalent rutin) using electroanalytical technique. For the evaluation of its detection capability, the results were compared with other electroanalytical techniques using analytical basis as samples of commercial coffee from different countries. The CPL-DNA: CN was used to determine the total amount of phenol in coffee samples (expressed by the equivalent rutin). Thus, it was possible to propose the CPL as an analytical tool for the detection of phenols. In this research, we developed several studies using different CPE to investigate the antioxidant natural product profile such as coffee samples, dry extracts of acerola, obtained by cyclic voltammetry (CV),) differential pulse voltammetry (DPV) and square wave voltammetry (SWV), which allowed to conclude classes of antioxidants present in the samples. The quantitative determination of these compounds was performed using the standard addition method by differential pulse voltammetry and electrochemical index (EI) has been proposed for estimating the oxidizing potential between different samples. Carbon paste electrode was also investigated using the different quality control samples commercialized produced from acerola employing DPV for the quantification of ascorbic acid (AA) in all samples, where the limit of detection (LOD) and limit of quantification (LOQ) was 0.31 and 0.96 μM and with excellent recovery between 97.4 to 102.2% The DPPH tests were used to compare the antioxidant activity in coffee and acerola samples. The Folin-Ciocalteu method was used to estimate the antioxidant activity of rutin from coffee samples. These methods proposed had advantages such as simplicity of sample preparation and the speed of the analysis of antioxidant capacity.Item Potencial antioxidante e atividade vasodilatadora de cervejas comerciais(Universidade Federal de Goiás, 2017-05-05) Oliveira Neto, Jerônimo Raimundo de; Vaz, Boniek Gontijo; http://lattes.cnpq.br/7814534710550639; Gil, Eric de Souza; http://lattes.cnpq.br/3218622824233303; Gil, Eric de Souza; Paula, José Realino de; Guedini, Paulo César; Cunha, Luiz Carlos da; Ferreira, Rafael de QueirozBeer is one of the oldest and most popular beverages consumed by mankind, the main classification of beers is the type of fermentation, divided into ale or lager, high and low fermentation, respectively. In this study, beer samples were divided into two portions, the first one for the spectrophotometric and electrochemical tests, which was used in natura form. And the second part was lyophilized, aiming at the concentration use standardization, alcohol withdrawal and guaranteeing an increase of durability, and then used in the pharmacological and chromatographic tests. The aim of this study was to investigate the antioxidant potential and vasodilator activity and correlate them with the phenolic profiles of twenty-two commercial beers. In addition, the antioxidant activity and the phenolic profile of hops and malts from different origins were also verified. From the raw materials, hops samples showed better antioxidant activity when compared to malt samples (p <0.05). The correlation between electrochemical index (EI) and total phenols (TPC), and radical scavenging methods, 1,1-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzthiazoline -6-sulphonic acid) (ABTS) was 0.86, 0.77 and 0.85 respectively for the hop samples. From the beers, ale group showed better antioxidant activity and TPC values when compared to the lager group. However, according to the Pearson correlation matrix, the correlation between IE with TPC, DPPH and ABTS was 0.86, 0.89 and 0.96 respectively for the lager group. While for the ale group, the correlations were not statistically significant (p> 0.05), mainly due to the turbidity interference of the samples during spectrophotometric assays. This fact reiterates the use of electrochemical methods, which minimize this type of problem besides being more sensitive and quick. Following the proposed electrochemical methodology, using the IE calculation, LB10 and AB1 samples obtained the highest indices. In the results of the principal components analysis (PCA) three groups were observed, where group III confirms LB10 and AB1 as the best antioxidants potential. LB10, AB1 and AB6 showed a maximal vasodilator effect of 92 ± 4, 88 ± 3 and 79 ± 3%, respectively. Both the vasodilator effect and the lipid peroxidation inhibition capacity may be associated with the presence of phenolic compounds in the beer samples, identified by mass spectrometry. This study, therefore, verified that the proposed IE methodology is an important tool to evaluate antioxidant properties and showed a good correlation with radical scavenging assays. Moreover, the study showed that beers may have a beneficial effect on the cardiovascular system, showing a good correlation of the vasodilator effect and antioxidant potential, which may be useful for future research on health, sensorial properties and quality parameters. Still from the standpoint of the quality of the beers, hop extracts as well as malt exhibited statistically results, corroborating to the applicability of these tools in the choice of these major ingredients improve the quality of the final product.