https://repositorio.uema.br/jspui/handle/123456789/2227 2026-04-13T18:52:46Z https://repositorio.uema.br/jspui/handle/123456789/5555 Título: Análise fitoquímica e antimicrobiana dos extratos vegetais de Vismia guianensis Abstact: Plants are frequently used for their therapeutic and pharmacological properties, which are used to treat diseases and infections through teas, lozenges, ointments, decoctions, and baths. The Vismia guianensis specie has been reported in the literature to have various antibacterial and antifungal properties. This study aimed to perform phytochemical screening of leaves and stems from the municipality of Matinha, Maranhão, using two cold extraction methods: maceration and percolation; to evaluate the quantification of total phenol and flavonoid contents in methanolic solutions of the dried extracts; and to analyze the antimicrobial potential of the extracts. The phytochemical screening consisted of 11 qualitative tests. The determination of phenolic compounds and flavonoids was performed in triplicate, using aluminum chloride as the reagent and a reading at a wavelength of 429 nm. For the former, Folin-Ciocalteu and sodium carbonate were used as reagents, and readings were made at a wavelength of 765 nm Both analytical curves were constructed with six standards. Antimicrobial assays were performed against Staphylococcus aureus (ATCC 25923), Streptococcus pyogenes (ATCC 19615), Pseudomonas aeruginosa (ATCC 27853), and Escherichia coli (ATCC 25922). The assays were performed using the agar diffusion technique, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The results showed that the leaf extract by maceration presented a higher concentration of total phenols (165.95 ± 1.34 mg EAG/g) and the stem extract by percolation, a higher amount of flavonoids (66.82 ± 1.70 mg EQ/g) while the stem extract by maceration presented the lowest concentrations (MIC and MBC) for the tested strains 2025-01-01T00:00:00Z https://repositorio.uema.br/jspui/handle/123456789/5479 Título: Uma sequência didática experimental para o ensino de misturas homogêneas e heterogêneas Abstact: This study aims to evaluate the impact of an experimental and contextualized didactic sequence on the teaching of homogeneous and heterogeneous mixtures, using the Three Pedagogical Moments as a methodological basis. The research, qualitative in nature and classified as action research, was conducted at Centro Educa Mais Paulo VI, involving 40 first-year high school students. The project was submitted to the Plataforma Brasil under the CAAE number 86357325.4.0000.5554, in accordance with opinion no. 7.413.797. The proposal sought to integrate theory and practice through experimental activities using accessible and everyday materials, promoting meaningful learning and the development of investigative and critical skills. Data were collected through questionnaires applied before and after the intervention, concept maps, and observation records. Data analysis was carried out using Discursive Textual Analysis. The project notably contributed to improving students’ understanding of mixture concepts, as well as increasing their interest and engagement in learning Chemistry. The main findings indicated an evolution in students' comprehension of homogeneous and heterogeneous mixtures, with an increase in the number of correct answers in the post-test and greater participation in experimental activities 2025-07-16T00:00:00Z https://repositorio.uema.br/jspui/handle/123456789/5478 Título: Percepção Crítica dos Discentes do Curso de Química Licenciatura para a Educação Inclusiva no Ensino Superior da Uema, São Luís - Ma, Brasil Abstact: This work had as its general objective to evaluate the profile of students of the Chemistry Degree Course, Center for Education, Exact and Natural Sciences of the State University of Maranhão (CECEN/UEMA), regarding the inclusion of students with disabilities in the institution. The research adopted a qualitative and quantitative approach, descriptive in nature, using a questionnaire with open- and closed-ended questions administered to students in the aforementioned program. The data were organized into graphs and discussed in light of the scientific literature on teacher training and inclusion. The results revealed that all participants reported being familiar with the term "atypical student," indicating a certain level of awareness regarding diversity in the educational context. However, only 23.1% of students considered themselves fully prepared to accommodate students with disabilities, while the majority expressed uncertainty, pointing to gaps in their initial training. Regarding institutional conditions, some students believe that UEMA is not prepared to adequately serve this population, and many report that they would not know how to respond to this reality. Suggested strategies to improve inclusion primarily involved teacher training, the use of adapted methodologies, assistive technologies, and individualized support. The discussion highlighted that, despite the existence of initiatives such as NAU (UEMA Accessibility Center), there is still a need to strengthen continuing education, expand inclusive experiences in the curriculum and improve the institution's infrastructure to ensure the effectiveness of inclusion in higher education 2025-07-17T00:00:00Z https://repositorio.uema.br/jspui/handle/123456789/5431 Título: Síntese verde e caracterização de óxidos de ferro com extrato de folhas de syzygium cumini para aplicações fotocatalíticas Abstact: The growing concern over environmental impacts drives the search for sustainable solutions in materials science, particularly in the development of clean technologies for wastewater treatment. In this context, the present study focused on the green synthesis of hematite (α-Fe¢O£) nanoparticles, both pure and doped with metal ions, using Syzygium cumini leaf extract as a reducing and stabilizing agent. This approach aligns with green chemistry principles, offering an eco-friendly synthesis route free of toxic reagents and with potential application in heterogeneous photocatalysis for the degradation of organic pollutants, such as methylene blue dye, in wastewater. The main objective was to develop and characterize α-Fe¢O£-based photocatalytic semiconductors and evaluate their optical and electrical properties. S. cumini leaves were collected and processed to obtain the plant extract, which was used to synthesize pure and doped α-Fe¢O£ with cerium (Ce) and nickel (Ni). The samples were characterized by X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). XRD confirmed the formation of the hematite crystalline phase, with characteristic crystallographic planes, while FTIR revealed bands associated with the plant extract's functional groups and iron oxides, along with signals related to the metallic dopants, indicating structural changes in the modified samples. The photocatalytic activity tests showed that the doped samples exhibited higher efficiency in degrading methylene blue under visible light compared to the undoped sample, suggesting that Ce and Ni doping enhanced charge separation and improved photocatalytic performance. Therefore, the results demonstrate the feasibility of a biosynthetic route using S. cumini as a green alternative for producing advanced nanomaterials with significant performance in water decontamination. This study contributes to the development of sustainable and innovative strategies for environmental remediation, combining science, technology, and ecological responsibility 2025-07-18T00:00:00Z