Programa de mestrado com caráter interdisciplinar. https://tedebc.ufma.br/jspui/handle/tede/3361 2026-06-24T23:16:49Z 2026-06-24T23:16:49Z MACHADO, Erika Aparecida Mendes https://tedebc.ufma.br/jspui/handle/tede/7053 2026-06-17T13:11:21Z 2026-03-25T00:00:00Z

Título: SÍNTESE VERDE E CARACTERIZAÇÃO DE NANOPARTÍCULAS DE PRATA UTILIZANDO PRÓPOLIS VERMELHA AMAZÔNICA PROVENIENTE DO PARÁ Autor: MACHADO, Erika Aparecida Mendes Primeiro orientador: DUTRA, Richard Pereira Abstract: Propolis is a resinous material produced by honeybees of the species Apis mellifera, widely used in folk medicine due to its antioxidant, anti-inflammatory, and antimicrobial properties. In recent years, its potential has been explored in nanotechnology, especially in the green synthesis of metallic nanoparticles, such as silver nanoparticles (AgNPs), which exhibit broad antimicrobial activity and the ability to interact with microbial structures. Given the increasing bacterial resistance to conventional bacteria, the integration of propolis and green nanotechnology emerges as a promising strategy for the development of new antimicrobial agents of natural origin. Therefore, this study carried out the green synthesis of silver nanoparticles using the hydroalcoholic extract of Amazonian red propolis as a reducing and stabilizing agent for silver ions. The Amazonian red propolis was evaluated for its reducing potential through the determination of total phenolic compounds, flavonoids, and antioxidant activity. The extract showed a high content of total phenolic compounds (228.6 ± 11.3 mg GAE/g) and flavonoids (131.9 ± 5.5 mg QE/g), in addition to significant antioxidant activity in the DPPH assay (EC50 = 22.2 µg/mL). Chemical characterization by HPLC revealed the presence of isoflavonoids such as calicosine, formononetin, and vestitol, compounds associated with the reducing capacity of the extract. Based on these properties, the green property of silver nanoparticles with red propolis (nAgPVA) was developed. The synthesis conditions were optimized using the Box–Behnken Design (BBD) experimental design. The formation of the nanoparticles was monitored by UV-Vis spectroscopy, in which synthesis 3 showed a plasmonic absorption band at approximately 425 nm after 24 h. Physicochemical characterization by dynamic light scattering (DLS) indicated an average hydrodynamic diameter of 91.3 to 534.3 nm, while a zeta potential of −4.7 to −27.2 mV promotes moderate electrical stability of the dispersions. In microbiological assays, nAgPVA showed antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa strains, with minimum inhibitory concentrations ranging from 15.3 to 49.3 mg/L. Furthermore, cytotoxicity assessment in GM-07492ª fibroblasts did not indicate cellular cytotoxicity under the tested conditions. The results demonstrate that Amazonian red propolis constitutes an efficient natural matrix for supplying nanoparticles with antibacterial potential and low cytotoxicity to normal cells, standing out as a sustainable alternative in combating bacterial resistance. Instituição: Universidade Federal do Maranhão Tipo do documento: Dissertação

2026-03-25T00:00:00Z MACHADO, Thalison de Sousa https://tedebc.ufma.br/jspui/handle/tede/7011 2026-06-16T16:42:45Z 2026-03-27T00:00:00Z

Título: Desenvolvimento e estabilidade de bebidas probióticas vegetais como estratégia de valorização da biodiversidade brasileira Autor: MACHADO, Thalison de Sousa Primeiro orientador: PEREIRA, Ana Lucia Fernandes Abstract: The growing demand for healthy foods has stimulated the development of probiotic plant-based beverages made from regional raw materials. In this context, the present study aimed to optimize the formulations and evaluate the stability of low-calorie probiotic beverages made from babassu coconut and mixed babassu coconut and cashew, promoting the valorization of Brazilian biodiversity. Beverages containing only babassu coconut and beverages supplemented with 13.9% cashew pulp were produced, with the initial pH adjusted to 5.6. Fermentation was carried out for 8 hours at 30 °C using Lacticaseibacillus casei. As a preliminary step, an online survey was conducted with participants to assess consumer attitudes, using word association, a hedonic scale, and purchase intention. Subsequently, a focus group was conducted with regular consumers of fermented beverages to identify preferences and assist in defining vanilla concentration and sweetness levels. After this stage, the following treatments were defined: T1 – babassu coconut probiotic beverage with vanilla; T2 – babassu coconut probiotic beverage with vanilla and xanthan gum; T3 – mixed babassu coconut and cashew beverage; T4 – mixed babassu coconut and cashew beverage with xanthan gum; all formulations were supplemented with 6% xylitol. Sensory acceptance was evaluated by untrained panelists using a hedonic scale, Just-About-Right (JAR) scale, Check-All-That-Apply (CATA), and purchase intention. On day 0 and day 42, the following parameters were analyzed: Lacticaseibacillus casei viability, pH, color, fatty acid profile, thiobarbituric acid reactive substances (TBARS), mineral composition, phenolic compounds and antioxidant activity, apparent viscosity, and sedimentation index.To assess sensory characteristics after 42 days of storage, the Flash Profile method was applied. For the sensory attributes evaluated using the hedonic scale, the mean scores for babassu coconut and vanilla probiotic beverages ranged from 6.75 to 7.52. The mixed beverages containing babassu coconut and cashew showed mean scores ranging from 6.12 to 6.95, indicating positive sensory acceptance. After refrigerated storage at 4 °C for 42 days, microbial viability ranged from 7.91 Log CFU/mL (T1) to 8.44 Log CFU/mL (T4). The addition of cashew resulted in a higher content of bioactive compounds and greater antioxidant activity, while xanthan gum increased viscosity and improved sedimentation stability. It can be concluded that mixed babassu coconut and cashew beverages demonstrate the potential of combining raw materials from Brazilian biodiversity to create innovative products. Instituição: Universidade Federal do Maranhão Tipo do documento: Dissertação

2026-03-27T00:00:00Z MARTINS, Gabriel da Silva https://tedebc.ufma.br/jspui/handle/tede/6990 2026-05-20T18:45:50Z 2026-03-26T00:00:00Z

Título: Síntese, caracterização e avaliação funcional de compósitos à base de vidro bioativo funcionalizados com extrato de Dysphania ambrosioides Autor: MARTINS, Gabriel da Silva Primeiro orientador: REIS, Aramys Silva dos Abstract: Bioactive glasses have gained prominence in regenerative medicine due to their ability to interact with biological tissues, induce hydroxyapatite formation, and act as systems for the controlled release of bioactive agents. In this context, the functionalization of these materials with natural products in composite formulations has emerged as a promising strategy to incorporate antimicrobial, anti-inflammatory, and antioxidant properties relevant to tissue repair. Among the species of interest, Dysphania ambrosioides (mastruz) has a broad ethnopharmacological background, together with preclinical evidence of antimicrobial, anti inflammatory, and wound-healing activity, which supports its investigation as a functionalizing agent for glass-based composites. Thus, this dissertation aimed to synthesize and evaluate the physicochemical, antimicrobial, and anti-inflammatory properties of borate-based bioactive glass composites functionalized with D. ambrosioides extract. The dissertation is organized into two chapters. Chapter 1 presents a scoping review on the biological potential of bioactive glasses functionalized with natural products in preclinical models, including 24 studies. Overall, functionalization favored the controlled release of bioactive substances, accelerated hydroxyapatite formation, and added antioxidant, antimicrobial, and immunomodulatory properties, without compromising cytocompatibility in most studies. However, important methodological heterogeneity was observed among the analyzed studies. Chapter 2 describes the development of bioactive glass-based composites functionalized with hydroethanolic extract of D. ambrosioides at concentrations of 6% and 12%, compared with the blank composite (0%). The extract showed 86.1 ± 8.88 mg GAE·g⁻¹ of total phenolic compounds and 42.49 ± 0.89 mg QE·g⁻¹ of total flavonoids, in addition to a chromatographic profile compatible with a kaempferol diglycoside. The analytical curve in PBS showed excellent linearity (R² = 0.999). In the release assays, there was a rapid initial release between 2 and 8 hours, more pronounced in the 12% formulation. In SBF, the materials promoted a gradual increase in pH and greater mass loss in the functionalized groups. The diffractograms indicated a predominantly amorphous matrix, with a reflection suggestive of hydroxyapatite at approximately 42° (2θ). Biologically, the composites maintained cell viability ≥ 80%, reduced nitric oxide production, and showed antibacterial activity against Staphylococcus aureus. Instituição: Universidade Federal do Maranhão Tipo do documento: Dissertação; Disponibilização parcial até 30/4/2028 por motivo de pedido de patente e publicação em periódico internacional.

2026-03-26T00:00:00Z SANTOS, Laryssa Stefany de Azevedo https://tedebc.ufma.br/jspui/handle/tede/6989 2026-05-20T18:05:45Z 2026-03-30T00:00:00Z

Título: Aspectos ecoepidemiológicos do araneísmo e escorpionismo no Maranhão, Brasil, 2013-2014 Autor: SANTOS, Laryssa Stefany de Azevedo Primeiro orientador: SANTOS, Leonardo Hunaldo dos Abstract: Spider and scorpion stings of public health concern constitute a significant public health problem in Brazil, representing an illness that compromises the quality of life of those affected, resulting in sequelae, temporary or permanent disabilities, and, in extreme cases, death. In this sense, the objective was to analyze the eco-epidemiological aspects of arachnid and scorpion stings in Maranhão reported during the period 2013-2024. This is an ecological study with distinct analytical measures, using microdata obtained from the files of the Notifiable Diseases Information System. A descriptive analysis of the sociodemographic and clinical epidemiological characteristics of the reported cases was performed. To identify the factors associated with arachnid stings, simple and multiple logistic regression models with odds ratios were used, considering a significance level of 5%. The incidence was determined by arachnid group, year, municipality, and Health Regions, and then a temporal trend analysis was performed using Prais-Winsten regression. Annual lethality was also calculated by arachnid group and according to the time elapsed between the bite and treatment. The association between the incidence of arachnid and scorpion stings and temperature and urbanization was estimated using robust multiple regression. Spatial dependence was confirmed using the Global and Local Moran's I test, while spatiotemporal scanning was employed using the Scan statistic to identify areas of epidemiological risk. The seasonality of accidents was verified using a temporal heat map. All statistical and spatial analyses were performed using RStudio software. The research was approved by the Research Ethics Committee of the Federal University of Maranhão. 21,677 cases of arachnid and scorpion stings were reported, with a predominance of scorpion stings (87.2%) compared to arachnid stings (12.8%). The condition primarily affected males (50.4%; 53.9%), those aged 20 to 39 years (40.7%; 34.6%), those of mixed race (80.8%; 81.8%), and those with primary education (complete and incomplete) (42.2% and 51.2%). Local and systemic complications were rare, while the cure rate (99.4% and 99.7%) exceeded the mortality rate (0.6% and 0.3%). Logistic regression reported that lesions located on the head, thighs, and trunk, accompanied by edema and delays in seeking medical attention, were more associated with spider bites. Investigation of temporal trends revealed increasing patterns of variation in incidence over the years. The analysis of spatial autocorrelation and risk clusters follows different patterns in different periods, highlighting areas of vulnerability throughout the state of Maranhão. Additionally, a significant association was found between arachnidism and urbanization, and between scorpionism and temperature and urbanization. These findings allow for the integration of environmental management actions, basic sanitation, and population education, as well as strengthening the health network with rapid access to diagnosis and appropriate treatment. The use of ecological and epidemiological tools to monitor spatial and temporal patterns improves prevention and control, promoting more effective and locally tailored interventions. Instituição: Universidade Federal do Maranhão Tipo do documento: Dissertação; Disponibilização parcial do conteúdo até 30/3/2031 por motivo de publicação de artigos referente aos resultados da dissertação

2026-03-30T00:00:00Z