https://repositorio.ifg.edu.br/handle/prefix/64 2026-09-12T09:57:22Z 2026-09-12T09:57:22Z Gonçalves, Anna Maria Ribeiro https://repositorio.ifg.edu.br/handle/prefix/2359 2025-08-18T15:47:35Z 2025-03-17T00:00:00Z

Título: Estudo fitoquímico e avaliação da toxicidade frente às larvas de Artemia salina Leach. do extrato de Miconia burchellii Triana (Melastomataceae). Autor(es): Gonçalves, Anna Maria Ribeiro Primeiro Orientador: Cunha, Gracielle Oliveira Sabbag Abstract: The vast biodiversity of the Brazilian Cerrado provides a great variety of plant species, which contain an abundance of molecules that may exhibit biological activities. However, this biological richness is severely threatened by fires and deforestation. A better utilization and rational exploration of the Cerrado's resources can be achieved through phytochemical studies alongside the investigation of the biological potential of its species. These studies not only contribute to the discovery and identification of new sources of bioactive molecules but also provide data that enrich the knowledge regarding the potential therapeutic use of plants from this biome. In this context, the aim of this work was to conduct a phytochemical study of the leaves of Miconia burchellii Triana (Melastomataceae), as well as to assess the toxicity of the extract obtained from the species. Toxicity was evaluated using the microcrustacean Artemia salina Leach, and the Median Lethal Concentration (LC₅₀) found for the ethanolic extract of the leaves was greater than 1000 µg/mL, characterizing the extract as non-toxic. The phytochemical prospecting was carried out through qualitative tests involving reactions with precipitate formation, color changes, and/or foam formation. The phytochemical prospecting of the Miconia burchellii extract revealed the presence of phenolic compounds, such as flavonoids and tannins, in addition to anthraquinones, coumarins, alkaloids, and terpenoid compounds. These results indicate the presence of bioactive compounds that may be associated with potential biological activities of the species, suggesting the need for further studies to explore its pharmacological properties and potential applications. Editor: Insitituto Federal de Educação, Ciência e Tecnologia de Goiás Tipo: Trabalho de Conclusão de Curso

2025-03-17T00:00:00Z Oliveira, Samanta Araújo de Matos https://repositorio.ifg.edu.br/handle/prefix/2258 2025-05-15T13:09:05Z 2025-03-21T00:00:00Z

Título: Estudo teórico do mecanismo de interação da dopamina e o radical hidroxila usando dinâmica molecular de Born-Oppenheimer Autor(es): Oliveira, Samanta Araújo de Matos Primeiro Orientador: Camargo, Lilian Tatiane Ferreira de Melo Abstract: Dopamine is a neurotransmitter synthesized by dopaminergic neurons located in the substantia nigra. It plays a fundamental role in functions such as motor control and cognition. Its dysregulation is associated with various conditions, including neurodegenerative diseases such as Parkinson's and Alzheimer's, as well as disorders like schizophrenia. Oxidative stress, resulting from excessive free radical production and/or deficiencies in antioxidant systems, is recognized as a key factor in the development of neurodegenerative diseases, as it can cause cellular damage and neuroinflammation. There are several experimental studies on dopamine and the hydroxyl radical; however, there is a scarcity of theoretical research exploring the molecular interactions involved in these processes. In this context, the present study employed Born-Oppenheimer Molecular Dynamics in conjunction with Density Functional Theory to investigate the interaction mechanism between dopamine and the hydroxyl radical. To achieve this, Fukui indices were calculated, and simulations were performed using Born-Oppenheimer Molecular Dynamics combined with Density Functional Theory. The Fukui indices indicated that the two hydrogen atoms bonded to the nitrogen (amine group) and the hydrogen bonded to the oxygen (phenolic group) are the most susceptible to radical attack. Simulations were carried out by varying the approach velocity of the hydroxyl radical, revealing that higher velocities result in molecular degradation, whereas lower velocities favor specific interactions, such as water formation. These findings enhance the understanding of the molecular-level interactions between the hydroxyl radical and dopamine. Editor: Insitituto Federal de Educação, Ciência e Tecnologia de Goiás Tipo: Trabalho de Conclusão de Curso

2025-03-21T00:00:00Z Santos, Geovanna Marques https://repositorio.ifg.edu.br/handle/prefix/2213 2025-04-14T15:21:55Z 2025-03-20T00:00:00Z

Título: Adsorção do corante azul de metileno em adsorvente da casca de pequi pura e modificada como alternativa para tratamento de efluentes. Autor(es): Santos, Geovanna Marques Primeiro Orientador: Pereira, Luciane Dias Abstract: Pequi peels account for approximately 84% of the weight of the fruit, and most of them are discarded inappropriately, causing environmental impact. Therefore, this research aimed to characterize the pure pequi peel and the peel modified with sulfuric acid as an adsorbent, aiming at their use in the adsorption of methylene blue dye in aqueous solution. The moisture content and ash content were determined; the modified pequi peel presented a lower moisture content compared to the pure pequi peel. The adsorption kinetics were applied with variations in contact time from 0 to 240 minutes between adsorbent and adsorbate. With the results obtained, the Freundlich and Langmuir adsorption isotherms were used to perform the adjustments of the results obtained. The pH of the solutions was determined, and a greater adsorption was observed in solutions with pH > 7. The kinetic study of the adsorption of methylene blue by the pure and modified pequi peel adsorbent concluded that the modified pequi peel was more effective in this adsorption, due to an electrostatic interaction between the active surface of the modified pequi peel and the dye molecules, which is cationic, favoring the adsorption in this solution. The results obtained were the adsorption capacity of 3.85 mg g-1 in the contact time of 5 min for the pure pequi peel and 3.97 mg g-1 for the modified pequi peel. Editor: Insitituto Federal de Educação, Ciência e Tecnologia de Goiás Tipo: Trabalho de Conclusão de Curso

2025-03-20T00:00:00Z Silva, Alessandra dos Santos https://repositorio.ifg.edu.br/handle/prefix/2178 2025-03-21T10:50:24Z 2024-10-10T00:00:00Z

Título: Fitoquímica e bioatividade de Acanthospermum australe (Loefl.) Kuntze (carrapicho): uma revisão sistemática Autor(es): Silva, Alessandra dos Santos Primeiro Orientador: Cunha, Gracielle Oliveira Sabbag Abstract: The plant Acanthospermum australe (Loefl.) Kuntze, belonging to the Asteraceae family and popularly known as “carrapicho” in Brazil, has several applications in traditional medicine. Its leaves and stems are used as antianemic, antifebrifuge, antiblenorrhagic, antimalarial, antidiarrheal, vermifuge treatment, in addition to being used in the treatment of ulcers, wounds and mycoses. This study focuses on the systematic analysis of articles that address the phytochemistry and/or evaluation of the biological activity of this species. A total of 130 works were reviewed, of which 25 met the established criteria. 46 isolated substances were identified, predominantly sesquiterpene lactones, associated with a variety of biological activities, including antiviral, antibacterial, antifungal, antiprotozoal, antioxidant, acute antiulcer, antineoplastic, inhibitory, insecticidal and larvicidal properties. Editor: Insitituto Federal de Educação, Ciência e Tecnologia de Goiás Tipo: Trabalho de Conclusão de Curso

2024-10-10T00:00:00Z