01.1 - Graduação (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/2
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Resultados da Pesquisa
Item Desenvolvimento de metodologia analítica sustentável para quantificação do corante artificial vermelho allura AC em balas alimentícias(2024-03-04) Coutinho, Maria Eduarda Bezerra; Santos, Jandyson Machado; Gomes, Bruna Ramos de Souza; http://lattes.cnpq.br/4086942894025609; http://lattes.cnpq.br/4137257750865101; http://lattes.cnpq.br/0500898038657595In Brazil, it is estimated that around 8% of children under 3 years of age have food allergies, caused by the inflammatory response after eating certain foods, especially sweets. This harmful effect may be associated with the presence of artificial colorings, such as Allura Red Ac (INS-129), which is commonly added to food candies. Therefore, industries must follow the standards established by the National Health Surveillance Agency (ANVISA), since excess of the Acceptable Daily Intake (ADI) of this dye can cause potential adverse risks, such as hypersensitivity reactions, similar to allergies, hyperactivity in children, as well as the risk of developing inflammatory diseases in the intestine, making it important to develop methods to quantify this dye in foods. Faced with this problem, the objective is to develop a sustainable analytical methodology capable of carrying out the determination and quantification of the Allura Red Ac dye in food candies, through a simple, easy-to-execute and economically accessible method, using the UV-Vis Spectrophotometry technique.. When carrying out the experimental analyses, analytical curves were obtained with standard solutions of the Allura Red Ac dye, where the relationship between the intensity of the coloring as a result of the increase in the concentration of the analyte was verified, thus obtaining a linear correlation between absorbance versus concentration, with coefficient of determination (R2) in analyzes by UV-Vis molecular absorption spectrophotometry. Quantification of three different bullets was carried out in three analytical protocols: I) the reference method of the Adolfo Lutz Institute that uses ammonia methanol; the proposed method using water as a solvent; III) the Adolfo Lutz Institute reference method with adaptations. A higher dye concentration was observed when the proposed method was used, with Confidence Level = 95%. Thus, it was possible to quantify the Red allura Ac dye in ten food candies sold in Brazil through Quimica Verde. The proposed method has the potential to be implemented as a routine method in the quality control of commercial candies.Item Estudo do poder catalítico de óxidos a base de resíduos de carapaças de sururu na síntese de biodiesel etílico e metílico a partir do óleo de fritura(2021-07-16) Silva, Jeane Rego da; Silva, Claudia Cristina Cardoso da; http://lattes.cnpq.br/9810071055429520; http://lattes.cnpq.br/5899758335174071The search for alternative solutions to oil consumption has been growing, due to the alarming acceleration of global warming. As an alternative, the use of green chemistry appears in order to revert this aggressive process to the environment, and biofuels appear as allies. Among biofuels, biodiesel is shown as an alternative in reducing greenhouse gases. Its production consists of the transesterification reaction of vegetable oil or animal fat with a short-chain alcohol, in the presence of a catalyst. On an industrial scale in Brazil, biodiesel is synthesized from soybean oil and methanol, under sodium methoxide catalysis. These 3 parameters do not favor the renewable character of biodiesel since; i) soy oil competes with a food; ii) methanol has a fossil origin which becomes meaningless when producing a renewable fuel; and iii) sodium methoxide is a homogeneous, non-reusable catalyst and needs to be removed with an aqueous solution in order to purify the biodiesel, generating a huge volume of effluents which, ultimately, also diminishes the environmental appeal of biodiesel as a biofuel. With all of this in mind, this work consisted of the study of the catalytic power of calcium oxide generated from the residues of shells from sururu, in order to produce biodiesel under the analysis of several parameters; i) ethanol and methanol as reagent alcohol; ii) neutral soybean oil and frying oil with 2 different acidity indices as starting oil; and iii) different reaction times in order to determine the kinetic behavior of this catalyst under each of these different parameters. Homogeneous catalysis was also performed in order to observe its behavior under extreme conditions and compare this behavior with heterogeneous catalysis. From studies of FTIR spectra, we verified the high catalytic efficiency of our oxide in the production of methyl biodiesel, both in neutral oil and in different acidic frying oils. This reaction success was attributed to the conversion of triglyceride to methyl esters above 95%. For the case of neutral oil, this efficiency was reached after 1 h of reaction and in the other cases after 3 to 4 h of reaction. The same success when observing the catalytic efficiency of converting soybean oil into ethylic biodiesel was also verified through the FTIR spectra, but this time without a calibration curve, which made a quantitative analysis impossible.Item Síntese verde e assinalamento completo de novos oxadiazóis 2,3-enopiranosídeos(2021-12-22) Acioli, Bianca Micaela Macario Gonçalves; Freitas Filho, João Rufino de; http://lattes.cnpq.br/9252404584350850; http://lattes.cnpq.br/7172195105463623In carbohydrate chemistry, the 2,3-unsaturated O-glycoside is a vital organic molecule with varied biological applications that can be enhanced by utilizing other functional groups that are linked through the glycosidic bond. In this work, the use of the 1,2,4-Oxadiazole functional group as an aglycone connected to the saccharide group was developed, considering that it has multiple applications, whether in medicinal chemistry, in the chemistry of new materials or also in agricultural chemistry. The synthesis and characterization of different arylamidoximes, precursors of the oxadiazole ring, are also described; of 1,2,4-oxadiazole and of the 2,3-enopyranoside ring, as sequenced reactions. Deriving from the synthesis of arylamidoximes, the results were obtained in good yields (80-90%) when compared with results already described in the literature. The six specimens of 3,5-Disubstituted-1,2,4-oxadiazole were synthesized through the methodology of heating without solvent and without base, which constitutes an innovative method to obtain 1,2,4-oxadiazoles, with yield ranging from 40-70%. After synthesizing the 1,2,4-oxadiazoles, they were reacted with tri-o-Acetyl-D-Glical in the presence of Montimorillonite K-10, as a catalyst, using a focused microwave under different reaction conditions, with yield of 25-50%. The structures of the compounds obtained were clarified using conventional spectroscopic techniques: Infrared and 1H and 13C Nuclear Magnetic Resonance. Despite the divergence between the yields obtained, this project demonstrates the importance of adopting green and eco-conscious synthesis, aiming at the preservation of the environment and the safety of employees for the construction of an inclusive and plural chemistry.