Programa de Pós-Graduação em Bioquímica
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Master Thesis Beta-Glucanas extraídas do fungo Caripia montagnei (Berk.) Kuntze: uma análise das suas propriedades antioxidante, antitumoral, antiangiogênica e anti-inflamatória de forma isolada e em sinergia com AINEs, L-NAME e ligantes de PPAR alfa e gama(Universidade Federal do Rio Grande do Norte, 2011) Castro, Allisson Jhonatan Gomes; Leite, Edda Lisboa; Cruz, Ana Katarina Menezes da; http://lattes.cnpq.br/9810605697247961; Martins, Daniella Regina Arantes; http://lattes.cnpq.br/3695151190501921; http://lattes.cnpq.br/7712988818433906; http://lattes.cnpq.br/6781850620408652Glucans are homopolymers of D-glucose with bioactive properties with direct influence o activation of leukocytes and antitumoral, antioxidant and immunomodulatory activities. The aim of, this paper was to verify the efect of p-glucans extracted from the mushroom Canpia m 9 the inhibition of the inflammation, angiogenesis and free radicais. The fraction polysaccna showed carbohydrate (98.5%), protein (1.5%) and 0.1 mg / mg of phenolic compounds. Its monosaccharide composition showed predominantly glucose by means of HPLC, with nuclear magnetic resonance (nmr) confirmed the presence of D-glucose to 103.5 ppm in P configuratio. The viability of fibroblasts in the presence of glucans from C. Montagnei at 25 uq was 83.3±17,6%, with high cytotoxicity on tumoral cells (HeLa) at 100 ug (94.36±2.3%). The anti-edematous activity observed at 90 mg/kg of Carípia montagnei was 90.7 ± 3.5%. The synergy with parecoxib showed was 81 3+7.4%, 100±12% to L-NAME and 97.8+10% with PFOA. In study made with carrageenan 91.043±7,3%. The production of nitric oxide with Caripia polysacchandes was (48.2%) was better than the activity of indomethacin. The glucans of C. montagnei showed significant antiangioge activity with 1 mg/egg (p>0.05). In total antioxidant activity and reducmg power was foundI for the relative antioxidant activity of BHT 57% and 84%, respectively. The evaluation of the inhibition of hydroxyl radical (1 mg/ml) was 38±0.01%, while for the lipid peroxidation was observed an inhibition of 37 6±0 16%. The present results showed that p-glucans from Carípia montagnei have inhibitory activity in these models of inflammation, angiogenesis and inhibition of free radicais.Doctoral Thesis Propriedades anti-inflamatórias e antioxidantes de blends do suco de Malpighia emarginata D. C. (acerola) e infusão de Camellia sinensis L. (chá verde)(Universidade Federal do Rio Grande do Norte, 2021-08-13) Souza, Natália Cabral; Pasquali, Matheus Augusto de Bittencourt; Dalmolin, Rodrigo Juliani Siqueira; 0000-0002-1688-6155; http://lattes.cnpq.br/2819075769518114; http://lattes.cnpq.br/2333591164264470; Schnorr, Carlos Eduardo; http://lattes.cnpq.br/9682316864110825; Lanza, Daniel Carlos Ferreira; http://lattes.cnpq.br/6851351991421755; Rocha, Hugo Alexandre de Oliveira; http://lattes.cnpq.br/4651814546820796; Gasparotto, Juciano; http://lattes.cnpq.br/4413537075363535Medicinal plants have been studied for centuries for their medicinal properties, including Malpighia emarginata D. C. (acerola) and Camellia sinensis L. (green tea) has been an alternative preventive and medicinal approach for various pathologies. In view of the potential anti-inflammatory and antioxidant uses, in this work we developed a mixture formulated in powder with Malpighia emarginata D. C. and Camellia sinensis L. which have a higher content of ascorbic acid and epigallatecatechin-3-gallate, respectively. The production of the blend was carried out through the spray drying process, using microencapsulation methods. Subsequently, the antioxidant and anti-inflammatory properties of the formulated blends were evaluated in an in vitro inflammatory model, using the RAW-264.7 macrophage cell line in two treatments, cells against extract and co-treatment, which are the blends against stimulated cells by lipopolysaccharide. We observed that co-treatment with blends was able to modulate redox parameters in cells during the in vitro inflammatory response. Furthermore, the co-treatment with the blends was able to modulate the inflammatory response, altering the secretion of IL-1β, IL-6, IL-10 and TNF-α cytokines. Thus, our results observed together demonstrate for the first time the synergistic antioxidant and anti-inflammatory effects of Malpighia emarginata D. C. and Camellia sinensis L. Thus justifying the additional use of this mixture in products that may bring health benefits, especially in terms of prevention of chronic diseases.Doctoral Thesis Sequências 2A e 2A-like em vírus com genoma de RNA: ocorrências e implicações evolutivas(Universidade Federal do Rio Grande do Norte, 2021-09-15) Lima, Juliana Gabriela Silva de; Lanza, Daniel Carlos Ferreira; Lima, João Paulo Matos Santos; 0000-0002-6113-8834; http://lattes.cnpq.br/3289758851760692; http://lattes.cnpq.br/6851351991421755; http://lattes.cnpq.br/1463822009424883; Gruber, Arthur; http://lattes.cnpq.br/8644261025719801; Bressan, Gustavo Costa; http://lattes.cnpq.br/1153853218347720; Fernandes, José Veríssimo; http://lattes.cnpq.br/7078820975978056; Araújo, Joselio Maria Galvão de; http://lattes.cnpq.br/64307749786437652A/2A-like sequences are oligopeptides that have approximately 18-22 amino acids and can mediate a co-translational "cleavage" of polyproteins in eukaryotic cells. These peptides are characterized by having a C-terminal motif of nine amino acids -(G/H)D(V/I)EXNPGP. These sequences are found in many viruses with positive single stranded and duble stranded RNA genomes that infect a variety of hosts ranging from protozoan to vertebrate species. Due to their cleavage capacity, 2A/2A-like sequences have been used in many heterologous co-expression systems. In view of the importance of 2A/2A-like sequences, the present work aimed to investigate and record the presence of these sequences in different virus species, and to assess the evolutionary importance of these sequences in the Totiviridae family. The first chapter of this work presents a review of 2A/2A-like sequences occurrence in different viral genomes through the alignment of these sequences with the NCBI database using the Blastp tool. This approach also enabled the identification of 69 new reports of viral sequences that contain 2A-likes, among which, 62 are ssRNA(+) viruses, 6 dsRNA viruses and one virus with a negative-sense single-stranded RNA genome (ssRNA(-)). This is the first report of this type of sequence in a ssRNA(-) virus. In the second chapter, the phylogenetic relationships among the Totiviridae family viruses are presented through a bayesian inference, from which it was possible to suggest the creation of the expanded Giardiavirus group, which comprises the viruses previously grouped in Giardiavirus, Artivirus and eight new viruses, which were divided into IMNV-like and GLV-like groups and had their ORF1 characterized using bioinformatics tools. During this characterization, sequences similar to 2Alikes were found in some viruses of the GLV-like group, which were called pseudo 2A-likes. To assess whether these sequences could become functional 2A-likes, the 2A-like ranking software was developed in this study. The analyses carried out in this program showed that viruses from the GLV-like group that infect arthropods have approximately 50 to 76% chance of becoming functional 2Alikes. The presence of pseudo 2A-likes in other dsRNA viruses was also verified using the NCBI database where it was possible to find 96 sequences that presented pseudo 2A-likes. The results presented in this study reinforce the diversity of hosts and genome structure of the Totiviridae family viruses, which can be explained by the emergence of functional 2A-like sequences from ancestral sequences described here as pseudo 2A-like. Thus, pseudo 2A-likes can be a key point in viral evolution, acting as a way to increase or maintain the complexity of the genome.Doctoral Thesis Bioquímica quântica da interação ligante-alvo no combate ao mycobacterium tuberculosis multirresistente(Universidade Federal do Rio Grande do Norte, 2021-10-08) Vianna, Jéssica de Fátima; Fulco, Umberto Laino; http://lattes.cnpq.br/9579151361576173; http://lattes.cnpq.br/3172779588083473; Silva Júnior, Edilson Dantas da; http://lattes.cnpq.br/5459705151588106; Oliveira, Jonas Ivan Nobre; http://lattes.cnpq.br/2461374517882321; Barbosa, Paulo Henrique Ribeiro; http://lattes.cnpq.br/1903813727934214; Vieira, Vinícius Manzoni; http://lattes.cnpq.br/7335017320399198Tuberculosis is a worldwide health problem caused by Mycobacterium tuberculosis and aggravated by the resistance mechanisms developed by this bacterium against the drugs used in its treatment. Thus, the development of drugs capable of eliminating multidrug-resistant strains, characterized by those that have resistance to the most important drugs - rifampicin and isoniazid - becomes crucial. Thereby, this work aims to perform a structural and energetic study of the kanglemycin and rifampicin interactions in complex with RNA Polymerase; also BDM72201, BDM72719, BDM76060 and BDM76150 with the transcriptional repressor EthR2, as a way to boost the action of ethionamide. Using crystallographic data from these systems, calculations of the interactions of each ligand with their respective receptors were performed within the density functional theory (DFT), and the binding energy of each molecule with the amino acid constituents of the binding site was obtained by applying the molecular fractionation with conjugate caps (MFCC). Thus, results showed that kanglemycin is able to bind to RNA polymerase in the same way as rifampicin, having -63.61 Kcal/mol and -65.68 Kcal/mol total energy, respectively, and sharing 79 residues at the binding site. In the presence of the S447L mutation, often associated with rifampicin resistance, kanglemycin maintains its strong interaction with its target, generating an overall energy of -64.00 Kcal/mol. BDM72201, BDM72719, BDM76060 and BDM76150 components share 68 residues of the same binding site. BDM72201 and BDM72719 attach to the site in a weaker way, showing energies of -19.56 Kcal/mol and -21.56 Kcal/mol, respectively; whereas BDM76060 (- 65.88 Kcal/mol) and BDM76150 (-66.13 Kcal/mol) produce stronger binding and have greater potential to act as EthR2 inhibitors. Therefore, it was evidenced that kanglemycin has great potential to be inserted into clinical practice as a rifampicin substitute and the BDM76150 as an ethionamide booster.Doctoral Thesis Estudo da vitamina A e do betacaroteno nanoencapsulado na obesidade(Universidade Federal do Rio Grande do Norte, 2021-09-23) Gomes, Camila de Carvalho; Morais, Ana Heloneida de Araújo; Passos, Thais Souza; 0000-0003-2054-1544; http://lattes.cnpq.br/9685790797554876; http://lattes.cnpq.br/1233944493334651; http://lattes.cnpq.br/1828493411721223; Rodrigues, Karla Danielly da Silva Ribeiro; http://lattes.cnpq.br/5658288179573297; Bezerra, Danielle Soares; http://lattes.cnpq.br/4545867903131219; Araújo, Kátia Gomes de Lima; http://lattes.cnpq.br/2178410237042942; Lima, Maira Conceição Jerônimo de Souza; http://lattes.cnpq.br/2695792864798488The increasing prevalence of obesity and chronic non-communicable diseases associated with it has increased, and the search for new strategies to control them. In this sense, vitamin A plays an important role in regulating body weight through the action of metabolites of this nutrient on different aspects in individuals with obesity. Based on this, this thesis is divided into two chapters. In the first chapter, a narrative review was performed to understand this relationship and the physiological effects of vitamin A on obesity. A search was carried out in the databases, selecting the studies that involved vitamin A or its active metabolites, encapsulated or not, and the role and relationship with obesity. Studies were found showing that there is an inverse relationship between adiposity and vitamin A concentration. In addition, it was demonstrated that encapsulating vitamin A or its precursors improves stability, bioavailability, and functionality and may favor better effects in the treatment of obesity. In the second chapter, a study was carried out to evaluate the impact of the crude extract rich in carotenoids from Cantaloupe melon (Cucumis melo L. var cantalupensis) nanoencapsulated in porcine gelatin (EPG) on the concentration of vitamin A in the liver of obese Wistar rats. The crude extract rich in carotenoids (CE) was obtained by processing, drying, and extracting bioactive compounds from the melon pulp, being used to synthesize the nanoformulation through the O/W emulsification technique. The nanoparticles were characterized in terms of physical and chemical aspects and evaluated the efficiency of incorporation of carotenoids. In the preclinical study, Wistar rats with obesity induced by a high glycemic index diet and a high glycemic load (HGLI diet) were divided into three groups (n = 5): 1. no treatment (HGLI diet + water), 2. treated with HGLI diet + CE (12.5 mg/kg), and 3. treated with HGLI diet + EPG (50 mg/kg) administered by gavage (1 mL) for ten days. These animals were evaluated for variation in dietary intake, retinol, and weight, hematological parameters, fasting glucose, and lipid profile. In addition, the investigation of hepatic retinol concentration and liver function was performed by determining the AST/ALT ratio and the FIB-4 (Fibrosis-4 Index for Liver Fibrosis) and APRI (AST to Platelet Ratio Index) scores. The results obtained for the characterization of the particles confirmed the presence of spherical particles with smooth surface, mean diameter of 80 (8.59) nm, polydispersion index of 0.47 (0.09), and the presence of new chemical interactions, indicating that CE was encapsulated in porcine gelatin. Furthermore, the CE incorporation efficiency was equal to 95.20% (0.74). For animals treated with EPG, lower dietary and retinol consumption was observed (p < 0.05). In addition, the same group of animals had significantly higher concentrations (p < 0.05) of hepatic retinol [266 (45) µg/g] when compared to the untreated group [186 (23.8) µg/g] and the one treated with CE [175 (8.08) µg/g]. The liver damage assessment scores did not show significant differences (p > 0.05), but the lowest means were observed in the group of animals treated with EPG. These findings suggest that nanoencapsulation promoted protection, guaranteed the absorption of carotenoids in the intestine, and bioconversion to retinol in the liver, without causing liver alterations. Thus, EPG presents itself as a candidate for future clinical studies, aiming to evaluate the beneficial effects of treating diseases that involve vitamin A deficiency, such as obesity.Doctoral Thesis Proteínas e peptídeos bioativos de vegetais e seus mecanismos envolvidos no controle glicêmico(Universidade Federal do Rio Grande do Norte, 2021-09-24) Costa, Izael de Sousa; Morais, Ana Heloneida de Araújo; Monteiro, Norberto de Kassio Vieira; 0000-0002-5847-5733; http://lattes.cnpq.br/8804303821523487; http://lattes.cnpq.br/1233944493334651; http://lattes.cnpq.br/2516503036471108; Rezende, Adriana Augusto de; http://lattes.cnpq.br/4245215108740331; Marinho, Emmanuel Silva; http://lattes.cnpq.br/3617101885685308; Aquino, Jailane de Souza; http://lattes.cnpq.br/8153908179932184; Evangelista, Karine Cavalcanti Mauricio de Sena; http://lattes.cnpq.br/2628723272728505Type 2 diabetes mellitus (T2DM) is a disease characterized by a chronic state of hyperglycemia, which can trigger changes in the body's functional and structural properties. Thus, the objective was to analyze the mechanism of action and the effect of bioactive proteins of plant origin in controlling blood glucose in the context of T2DM, seeking new therapeutic targets for this disease. This thesis was divided into three chapters. In the first and second, there are the protocol and the systematic review (SR), respectively, aiming to answer the question: how the isolated (pool) and purified proteins and peptides extracted from vegetables act to reduce blood glucose in experimental models of T2DM? The protocol was registered in the International Prospective Registry of Systematic Reviews (PROSPERO) under CRD42019110956. For SR, experimental studies were selected with bioactive proteins and peptides of plant origin that affect the glycemic control of animals with experimentally induced T2DM. The articles were selected according to the PICOS strategy (population, interventions, control and outcome) in the following databases: PubMed, ScienceDirect, Scopus, Web of Science, EMBASE and Virtual Health Library. The initial search retrieved 916 articles. After reading the title, abstract and keywords, 24 articles were eligible for a full reading. After this process, five articles were included in the SR. The study's assessment of evidence and risk of bias was performed using the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) protocol. As a result of the SR, all pathways stimulated by the five molecules of vegetable protein origin mediated secondary stimuli in the insulin signaling cascade up to glucose uptake. In the third chapter, a preclinical study with the trypsin inhibitor isolated from tamarind seed (TTI) and in silico analysis with the TTIp model number 56 and conformation number 287 (TTIp 56/287) was presented. In the preclinical study, the effect of TTI on the hyperglycemic state in Wistar rats with T2DM induced by a high glycemic index and high glycemic load (HGLI) diet for 17 weeks was evaluated. From the diagnosis of T2DM, the animals (n = 15) were divided into three groups (n = 5): 1. T2DM without treatment; 2. T2DM treated with a standard diet (nutritionally adequate); and 3. T2DM treated with TTI (25 mg/kg), administered by oral gavage (1 ml) for 10 days. After this period, fasting insulin and glycemia were analyzed, in addition to the Homeostasis model assessment for insulin resistance (HOMA-IR) and β-cell function (HOMA-β) models. At the end of the analysis, the group of animals that received the treatment with the TTI had lower fasting glucose concentration (p = 0.0031) and the HOMA-IR index (p = 0.0432), in addition to being higher HOMA-β index (p = 0.0052) when compared to the animals of the other groups evaluated. In the study by molecular dynamics simulation, the interaction between the TTIp 56/287 and the insulin receptor (IR) (PDB ID 4OGA) was observed. The TTIp 56/287-IR (-1591.54 kJ mol-1 ± 234.90), showed lower potential energy of interaction (EPI) compared to the Insulin-IR (Ins-IR) (-894.98 kJ mol-1 ± 32.16), with distinct amino acid residues involved in this interaction. Thus, TTI acted as a hypoglycemic agent in a preclinical study, and its connection to RI can trigger this action. This thesis shows that plant proteins, such as TTI, have antidiabetic potential as an adjuvant in glycemic control by acting in metabolic pathways common to RI.Master Thesis Comparação do potencial antioxidante in vitro, em cultivo de células e in vivo de fucoidans obtidos comercialmente(Universidade Federal do Rio Grande do Norte, 2021-10-08) Silva, Maylla Maria Correia Leite; Câmara, Rafael Barros Gomes da; Rocha, Hugo Alexandre de Oliveira; 0000-0003-2252-1221; http://lattes.cnpq.br/4651814546820796; http://lattes.cnpq.br/9200036511632745; http://lattes.cnpq.br/3703561529618882; Lucena, Eudes Euler de Souza; http://lattes.cnpq.br/6969519171915250; Pinhal, Maria Aparecida da Silva; http://lattes.cnpq.br/7511274763693292Fucoidans are sulfated L-fucose-rich polysaccharides that are extracted from brown seaweed. These polymers are already commercially available and have been evaluated for various purposes. One of the most evaluated activities is the antioxidant, among the fucoidans that have already been analyzed for antioxidant capacity are the fucoidans from brown seaweed: Undaria pinnatifida; Macrocystis pyrifera and Fucus vesiculosus. However, the antioxidant activity of fucoidans from the respective seaweeds have not yet been compared. Thus, the objective of this work was to identify which of these fucoidans, which are commercially obtained (Sigma-Aldrich), has the best antioxidant activity. Therefore, the fucoidans were analyzed for their physicochemical composition, the results obtained showed that they are rich in fucose and sulfate. And regarding the apparent molecular mass, it was found that it ranged from 70.4 to 168.5 kDa. The fucoidan from U. pinnatifida being the largest polymer. In vitro antioxidant tests all showed fucoidans with moderate activity, except for the H2O2 scavenging assay, where all fucoidans exhibited high activity. When fucoidans were evaluated under macrophage cell culture conditions (RAW 264.7) by MTT (3-(4,5-dimethylthiazol-2-yl) 2,5- diphenyl tetrazolium bromide) and live/dead reduction assays, after induction of oxidative stress with H2O2, it was observed that fucoidans reduced the effect of H2O2 on the metabolism of these cells, especially the fucoidan from F. vesiculosus (5 mM). The data obtained in vitro and with cells provided support for the performance in vivo tests with the Danio rerio (zebrafish) embryo model. Two analyzes were carried out: determination of the survival rate of the embryos and quantification of the fluorescence intensity of the hatched larvae. It was observed that in the presence of fucoidans and H2O2, the survival rate of the embryos was little affected, compared to the treatment that received only H2O2 (0.4 mM), where there was a 50% reduction in the survival rate. The evaluation of larvae treated with fucoidan and with H2O2 (0.4 mM) showed that the lowest percentage of fluorescence intensity was observed with those treated with F. vesiculosus and M. pyrifera fucoidan. Considering the results of the tests carried out, fucoidan from M. pyrifera is pointed out as the fucoidan with the best antioxidant potential, especially in vivo tests. Thus, fucoidan from M. pyrifera is the most promising in terms of antioxidant activities.Master Thesis Caracterização de comunidades e isolados bacterianos obtidos a partir de amostra de petróleo de pré-sal brasileiro sob cultivo em presença de CO2(Universidade Federal do Rio Grande do Norte, 2021-07-20) Barbalho, Kamilla Karla da Silva; Lima, Lucymara Fassarella Agnez; http://lattes.cnpq.br/1083882171718362; http://lattes.cnpq.br/8583882001958993; Thompson, Fabiano Lopes; http://lattes.cnpq.br/4148145822928884; Melo, Vânia Maria Maciel; http://lattes.cnpq.br/1572504650930605Microorganisms represent the largest biomass on Earth and are directly related to biogeochemical cycles. It has been described that microbial activity affects the production chain related to the oil and gas sector, being of interest the knowledge about the microbiology associated with reservoirs, aiming the optimization of the production chain, as well as the mitigation of environmental impacts due to environmental contamination by hydrocarbons. The Brazilian pre-salt reservoirs are extreme environments with high carbon dioxide (CO2) concentration and high depth, whose microbiology is still poorly understood. The objective of this work was to characterize bacterial communities and isolates obtained from a sample of pre-salt oil submitted to cultivation at high CO2 concentration. From an oil sample, six consortia were obtained and analyzed, organized in two groups: three undefined microbial consortia grown at high CO2 concentration and the other three obtained from the same sample under atmospheric aeration and later submitted to high CO2 concentrations. The microbial consortia were characterized for: i) biosurfactant (BS) production; ii) growth curve in the presence of hydrocarbons as carbon source; and iii) taxonomic and functional characterization by metagenomic sequencing. Functional assays of the consortia showed that three are able to produce BS molecules capable of generating emulsion, whereas none of the consortia is able to disperse oil. The growth curves showed that five consortia are able to grow in the absence of external carbon sources, indicating the occurrence of inorganic carbon fixation, which was corroborated by the metagenomic sequencing of the consortia via identification of sequences assigned to the genus Ochrobactrum, which is able to fix carbon. In the consortia, the most abundant phyla were Proteobacteria, Actinobacteria, and Firmicutes, and the consortia submitted to high CO2 concentration, after growing in O2, were more diverse than the consortia grown in high CO2 concentration. As for the metabolic profile, the most enriched pathways in the consortia grown in CO2 were the amino acid metabolism and carbohydrate metabolism pathways. Nineteen bacterial isolates were obtained from the consortia, and nine were characterized and tested. For the isolates the following assays were performed: i) BS production, ii) hydrocarbon degradation capacity, iii) cellular hydrophobicity, and iv) enzymatic activity of hydrolases. Of these, five were able to degrade between 50% and 80% of the xylene and toluene fractions, and eight others degraded 100% of the gasoline, diesel and kerosene fractions. It is concluded that the growth of undefined consortia in O2 leads to a greater diversity of microorganisms, that CO2 inhibits BS production, and that isolates and microbial consortia from the pre-salt show promise as a source of bioremediation products, as well as hydrolases with potential industrial application.Master Thesis Atividade antibacteriana de magnetita (Fe3O4) isolada e associada a campos eletromagnéticos sobre Escherichia coli DH5a pVAX-1 (resistente à canamicina)(Universidade Federal do Rio Grande do Norte, 2021-06-30) Santos, Sunamita da Silva Barbosa; Silva, Marcelo de Sousa da; http://lattes.cnpq.br/1295430560645312; http://lattes.cnpq.br/6988181736543670; Melo, Maria Celeste Nunes de; http://lattes.cnpq.br/0580551464788795; Barbosa, Júlio César Pereira; http://lattes.cnpq.br/0437190557200470Due to the increase in bacterial resistance in recent years, research and development of alternative antibacterial therapies has become necessary and, in this sense, the use of magnetic fields has been explored as it is a non-pharmacological therapy and, therefore, probably exempt of the molecular effects of the resistance phenomenon. At the same time, nanoparticles with magnetic properties, especially magnetite (Fe3O4), are still little explored in terms of their antibacterial potential. In this context, the present work evaluated the intrinsic antibacterial properties of magnetite nanoparticles, synthesized by high-energy milling, and their association with a variable external magnetic field of 70 mT at 10 Hz on Escherichia coli DH5α pVAX-1. After synthesis, the nanoparticles were characterized as to their composition and primary size, by X-ray diffraction (XRD); as to its hydrodynamic size, by dynamic light scattering (DLS) and as to its surface charge, by zeta potential. Subsequently, in vitro assays were performed, in which alterations in the bacterial inhibition curve were investigated; in bacterial morphology, using microscopy (SEM), and in bacterial surface load, using zeta potential. The association between the antibiotic kanamycin and magnetite was also evaluated regarding the potentiated effect between the substances. Exposure to isolated magnetite, or combined to a magnetic field, generated significant bacteriostatic effects, in addition to morphological changes in the bacterial surface and an increase in the zeta potential of the suspension. The use of magnetite nanoparticles also potentiated the inhibitory effect of the antibiotic kanamycin, pointing to a second option for use as an adjunct to antibiotic therapy. The results presented reveal important antimicrobial potential and additional in vivo tests are needed to prove the importance of the effects observed in a biological system.Master Thesis Efeito do inibidor de tripsina isolado da semente de tamarindo (Tamarindus indica L.) nanoencapsulado sobre parâmetros bioquímicos e histopatológicos do fígado de ratos Wistar alimentados com dieta de alto índice glicêmico(Universidade Federal do Rio Grande do Norte, 2021-05-28) Aguiar, Ana Júlia Felipe Camelo; Morais, Ana Heloneida de Araújo; Passos, Thais Souza; 0000-0003-2054-1544; http://lattes.cnpq.br/9685790797554876; http://lattes.cnpq.br/1233944493334651; http://lattes.cnpq.br/3937321074677193; Moura, Sérgio Adriane Bezerra de; http://lattes.cnpq.br/1323062374722389; Ferreira, Ederlan de Souza; http://lattes.cnpq.br/4952207117831158There has been a nutritional transition based on diets composed of foods with a high glycemic index and a high glycemic load and ultra-processed foods worldwide. This, associated with other factors, is crucial for increasing the obesity prevalence and various diseases, including the disease Non-Alcoholic Fatty Liver (NAFLD). NAFLD ranges from steatosis and steatohepatitis to severe conditions, such as cirrhosis and hepatocellular carcinoma. NAFLD treatment is a clinical necessity not answered. Thus, several studies have sought new therapies not only for NAFLD but also for obesity. Among them, we highlight the findings related to the trypsin inhibitor isolated from tamarind seeds (TTI) nanoencapsulated in chitosan and whey protein isolated (ECW). Therefore, the present study aimed to investigate the effect of ECW on the liver status of Wistar rats fed a high glycemic index and high glycemic load diet (HGLI diet). First, nanoparticles with and without TTI, respectively ECW and CW, were obtained by the technique of nanoprecipitation in an organic solvent and, characterized by morphology (SEM), particle size (Laser diffraction), chemical interactions (FTIR), and efficiency of encapsulation. The animals were divided into four groups, containing five animals, each treated for ten days with 1. HGLI diet and water (1 mL), 2. standard diet and water (1 mL), 3. HGLI diet and ECW (12.5 mg/kg in 1 mL), and 4. HGLI diet and CW (10.0 mg/kg in 1 mL). The hematological biochemical parameters of renal and hepatic involvement were evaluated (liver enzymes, AST/ALT ratio), lipid profile, fasting glucose, insulin and insulin resistance, and β-cell homeostasis model (HOMA-IR and HOMA-β, respectively). Besides, liver scores FIB-4 (Fibrosis-4 Index for Liver Fibrosis) and APRI (AST to Platelet Ratio Index) were also investigated, and the liver histopathology of the animals was evaluated. Given the results, smooth, spherical nanoparticles were obtained in nanometric diameter (120.7 nm) containing TTI. In animals, ECW reduced (p < 0,05) fasting blood glucose levels by 17%, AST in 39%, and alkaline phosphatase in 24%, also significantly reduced (p < 0,05) the two scores of assessment of liver fibrosis, APRI, and FIB-4, and presented a better aspect of liver morphology when compared to the other groups. Thus, it was possible to show that the ECW promoted a new functionality for the isolated TTI, promoting benefits on the liver injury caused by the HGLI diet, considering the biochemical, morphological, and liver fibrosis evaluation parameters.