https://ri.ufs.br/jspui/handle/riufs/18885 2026-07-15T23:26:48Z https://ri.ufs.br/jspui/handle/riufs/25290 Título: Estudos in silico na busca de alcaloides inibidores do Fusarium oxysporum Autor(es): Farias, Beatriz Lobato Nogueira Abstract: The fungus Fusarium oxysporum is a widely distributed phytopathogen responsible for significant agricultural losses and capable of acting as an opportunistic agent in human infections. Control methods commonly employed include the application of fungicides and crop rotation; however, the microorganism has shown resistance mechanisms to different antifungals, limiting the effectiveness of available treatments. In this context, the search for new substances with inhibitory properties becomes essential, aiming at the development of therapeutic alternatives and the improvement of strategies to combat the pathogen. This study aims to identify alkaloids with inhibitory potential against F. oxysporum through an in silico approach. A database from CHEMBL was selected, containing structures previously evaluated in minimum inhibitory concentration (MIC) assays. Subsequently, alkaloid-like structures were analyzed using genetic algorithm and random forest tools; 6 molecular descriptors were selected for class AB. The developed classification model presented consistent statistical parameters in Cohen's kappa values (internal = 0.935; cross = 0.751; external = 0.740), indicating predictability and robustness. Subsequently, the models were evaluated through statistical validation, including the confusion matrix, class statistics (recall, precision, sensitivity, and specificity), general statistics (prediction and overall error, Cohen's kappa, correctly and incorrectly classified structures), and ROC curve. Following virtual screening, structures of 70 active alkaloids with antifungal potential were selected based on 85% reliability. The results highlight the applicability of chemoinformatics in supporting experimental validation and the study of new bioactive structures. 2026-01-29T00:00:00Z https://ri.ufs.br/jspui/handle/riufs/25170 Título: Análise da irradiação solar e variáveis físicos, químicas e microbiológicas no processo de fermentação do mosto da uva (vitis labrusca) para a produção de vinho no semiárido sergipano Autor(es): Souza, Helder Túlio Rodrigues de Abstract: The dissertation's main objective is to analyze the influence of solar radiation and physical, chemical and microbiological variables in the fermentation process of grape must (Vitis labrusca) for winemaking in the semi-arid region of Sergipe, more specifically in the municipality of Canindé do São Francisco, since in the fermentation process of grape must, it is necessary to analyze and evaluate such points, since these indexes allow to evaluate the quality of production in the region for viticulture, and with this, to develop strategies, processes and biotechnologies that aim at sustainability for the purpose of improving wine production. 2026-02-23T00:00:00Z https://ri.ufs.br/jspui/handle/riufs/23635 Título: Modelagem molecular do receptor canabinoide tipo-1 do papagaio-verdadeiro (Amazona aestiva): análise dos modos de acoplamento de fitocanabinoides Autor(es): Santos Júnior, Elpídio Vicente dos Abstract: The cannabinoid type-1 receptor (CB1) has received increasing attention from the scientific community due to its central role in maintaining homeostasis, particularly for its pharmacological functions in the nervous and immune systems. Present in all vertebrates, CB1 is also attracting interest due to the therapeutic potential of secondary metabolites from Cannabis sativa (Linnaeus, 1753), whose ligands exhibit high affinity for the canonical binding site, stimulating the development of drugs aimed at modulating the endocannabinoid system, including potential applications in wild bird medicine. In this study, a three-dimensional model of the CB1 receptor from Amazona aestiva (Linnaeus, 1758), a South American parrot species whose experimental structure has not yet been elucidated, was constructed. Thus, the target receptor was obtained by homology, refined in membranes using 500-ns molecular dynamics simulations with GROMACS, and used in the virtual screening of several C. sativa secondary metabolites compiled from the literature (567 compounds from de plant, plus the reference agonist). Molecular docking was performed in the receptor active site using the GOLD genetic algorithm, using the full agonist CP55,940 as a control. The results showed that cannabisins, the ten variants tested, exhibited a high tendency to interact with the CB1 receptor, surpassing even the reference ligand CP55,940. The model also predicted high affinity for cannabisol, a dimeric phytocannabinoid derived from Δ9-tetrahydrocannabinol, recognized for its potent CB1 agonist activity. Another relevant finding was cannabitwinol, a cannabidiol dimer associated with thermoregulatory receptors, whose high affinity suggests possible bivalent activity, expanding theoretical hypotheses about its mechanisms of action. Finally, this study highlights the applicability of in silico approaches in the screening and prioritization of promising drug candidates selective for CB1 from A. aestiva, providing support for experimental investigations into the pharmacological relevance of C. sativa metabolites in wild birds. 2025-01-28T00:00:00Z https://ri.ufs.br/jspui/handle/riufs/23633 Título: Potencial antimicrobiano e antioxidante de óleos essenciais obtidos de diferentes genótipos de Lippia gracilis Schauer Autor(es): Oliveira, Weslei da Silva Abstract: Due to the increasing demand for new compounds with applicability in medicine, the food industry, pharmacology, and therapeutics, the use of essential oils has gained prominence in recent years. These compounds possess chemical properties that allow their application in different areas of biotechnology. Based on this, the aim of the present study was to evaluate the antimicrobial and antioxidant activities of essential oils from different genotypes of Lippia gracilis Schauer, as well as to apply a predictive model to analyze the microbial growth kinetics of pathogenic strains exposed to different pH conditions (5.0, 6.0, and 9.0), essential oil concentrations (1.32, 2.64, and 5.29 mg/mL), and pH + essential oil combinations. Antimicrobial activity was assessed using the disk diffusion method, Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC). Most strains showed high to extremely high sensitivity to the oils. Pseudomonas aeruginosa was the only bacterium not sensitive. MIC and MBC values ranged from 1.32 to 42.37 mg/mL. Antioxidant activity was determined using the ABTS method (656.2–1,185.0 μmol Trolox/L), FRAP method (1,296.8–2,656.2 μmol Trolox/L), and DPPH method (314.6–446.6 μmol Trolox/L). In the predictive experiments, the essential oil that showed the lowest MIC and MBC values against most bacteria was used. In treatments varying only oil concentrations, no growth was observed for most strains. Furthermore, the combination of pH + essential oil was effective in inhibiting or reducing bacterial growth rate and prolonging the lag phase duration. Overall, L. gracilis essential oils demonstrated excellent potential for application as natural antioxidants and antimicrobial agents. 2025-10-09T00:00:00Z