Navegando por Assunto "Antioxidante"

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Acesso aberto (Open Access)
Caracterização anato-histoquímica e nutricional de Piper peltatum L. (Piperaceae): uma planta alimentícia não convencional ocorrente na Amazônia
(Universidade Federal do Pará, 2024-02-29) PALHETA, Gredany Rodrigues; HERRERA, Raírys Cravo; http://lattes.cnpq.br/215377919730650; HTTPS://ORCID.ORG/0000-0002-9699-8359; REIS, Alisson Rodrigo Souza; http://lattes.cnpq.br/7258026642139407; https://orcid.org/0000-0001-7182-4814
Unconventional food plants (UFP) are a group of edible and medicinal species not commercialized on a large scale, including leaves, flowers, fruits, roots, among other parts. Its origin is associated with traditional people who passed on their knowledge to family members. Given the diverse Brazilian flora, especially Amazonian species, there are still few scientific reports about these plants. Therefore, it is necessary to apply new methodologies for taxonomic identification, presence of substances and nutritional profile of edible plants. Because of this, the work aimed to diagnose the scientific production of non-conventional food plants and anatomically and nutritionally characterize the caapeba-amazônica leaf (Piper peltatum L.), contributing to scientific knowledge of the Amazonian flora. For scientometrics, the descriptors “Plantas alimentícias não convencionais” were used in Google Scholar and “Unconventional Food Plant*” in Scopus and Web of Science. For data visualization, R language was used by the Bibliometrix package and the Publish or Perish software. Astra Blue and Basic Fuchsin reagents were added to the anatomical sections of the leaf and Toluidine Blue, Ferric Chloride, Lugol and Sudam III were added for histochemistry. The Nutritional characterization was determined by analyzes of Moisture, Water Activity, Ph, TTA, TSS, Ashes, Lipids, proteins, carbohydrates and antioxidant profile. In the results, an increase in publications about UFP was observed and the theme has been published in journals with a high Qualis stratum. Related keywords indicate experimental studies as relevant themes for publication. The caapeba-amazônica is a species present in UFP articles although little quoted and studied. The anatomical characteristics of the P. peltatum leaf are consistent with the piperaceae family. In its histochemical test, the presence of lipids, phenolic compounds, starch and cellulose was observed. From the physiochemical results, it was observed to be perishable and should be stored in refrigeration. It is a source of minerals, carbohydrates, lipids and proteins, in addition to being an antioxidant. It is important to maintain new studies to contribute to the knowledge of UFP species, including Amazonian ones, such as P. peltatum, which presents substances with medicinal and food properties similar to other UFP hardwoods. Its consumption depends on the central vein of the leaf being removed, softened by cooking and similar culinary preparation of the cabbage leaf. It is a food and nutrient alternative, including for individuals affected by food insecurity. Its consumption favors agroecology and conservation of Amazonian biodiversity.
Acesso aberto (Open Access)
Efeito protetor do ácido alfa lipóico sobre a lesão hepática, induzida por dapsona em modelo animal
(Universidade Federal do Pará, 2018-07-06) SAKAI, Joni Tetsuo; MONTEIRO, Marta Chagas; http://lattes.cnpq.br/6710783324317390
The liver is the main organ involved in the biotransformation of xenobiotics, with the ability to convert hydrophobic compounds into water soluble, more easily eliminated by the body. Dapsone (DDS) is part of the multidrug therapy (MDT) of leprosy treatment, its metabolite is related to the generation of free radicals in hematological and neural cells, being thus directly involved in the main adverse reactions caused by its use. Due to its conversion cycle, which involves the reaction with iron present in the liver, DDS also accumulates in the liver, remaining longer in this organ, thus favoring tissue damage, such as drug hepatitis. In this context, the objective of the present study was to evaluate the protective effect of Alpha Lipoic Acid (ALA) on the liver damage caused by DDS in mice, after treatment. In this study, treatment with dapsone induced hepatic damage, with increase of Aspartate aminotransferase and alkaline phosphatase, as well as oxidative stress, by increasing lipid peroxidation and decreasing both glutathione levels and total antioxidants. These processes may be associated with accumulation of hepatic iron in the body. Already post-treatment with the antioxidant Alpha Lipoic Acid, this was able to decrease the levels of Aspartate aminotransferase and Alkaline Phosphatase, reverse lipid peroxidation and raise levels of GSH and total antioxidants. In addition, ALA also inhibited the accumulation of hepatic iron induced by dapsone in mice. Our results indicate that the antioxidant tested has a therapeutic potential against hepatic damage caused by dapsone in patients with leprosy.
Acesso aberto (Open Access)
Extração utilizando óleo vegetal e assistida por ultrassom de biocompostos da pimenta cumari-do-pará (capsicum chinense Jacq) em diferentes estádios de maturação e localidades
(Universidade Federal do Pará, 2017-03-23) CARDOSO, Raiane Vieira; RODRIGUES, Antonio Manoel da Cruz
The extraction of blend is one of the most critical steps in the polls with natural products, because your efficiency depends on several parameters, such as the sample type, type of analytes to be extracted, location where these analytes are sampled, type of solvent extractor and method of extraction, among others. In this study the objective of performing the ultrasound-assisted extraction of cumari pepper blend-do-pará (Capsicum chinense Jacq) grown in two different locations in the State of Pará (Santo Antônio do Tauá and Igarapé-Açu) and with different level of maturation using vegetable oil as a solvent. The centesimal composition (moisture, ash, proteins, carbohydrates and lipids), was made in conjunction with the quantification of soluble solids, acidity, pH and color. For conducting the tests of extraction of bio- and antioxidant capacity, the pulps were freeze dried and subjected to extraction with organic solvents and ultrasound-assisted extraction using vegetable oils (soybean, Brazil nuts and palm olein). In the extracts were analyzed concentrations of vitamin C, total carotenoids and phenolic compound capsaicin. The antioxidant activity was measured by β-carotene system/linoleic acid and ABTS radical test. The results indicated that the ash content is not influenced by the degree of maturation at both locations studied. About the color, the biggest b * parameters, index Chroma (C) and the Hue Angle values (ºc) near 90° were found in Peppers mature, demonstrating that these fruits boast yellow colour when they reach maturity. For bioactive compounds and antioxidant activity, it was observed that for the majority of the compounds analyzed the degree of ripeness and the location interfere and highest values were found for the mature peppers of Igarapé açu. The same behavior was observed for extracts obtained from vegetable oils, being soybean oil which obtained greater values. The fruits of peppers had significant antioxidant activity and the Pearson correlation results have shown that phenolic compounds were the main responsible for antioxidant activity.
Acesso aberto (Open Access)
Investigação fitoquímica e atividade biológica das cascas de Luehea speciosa willd
(Universidade Federal do Pará, 2017-12-21) NASCIMENTO, Maisa Carmen Batista do; BARBOSA, Wagner Luiz Ramos; http://lattes.cnpq.br/1372405563294070
The barks of Luehea speciosa, family Malvaceae, are used in traditional medicine to treat dysentery, rheumatism, tumors, bronchitis, skin wounds, weight loss and others diseases. However, studies give little information about the species in the literature. Thus, it is of great interest to investigate its chemical constitution and biological activities, since the scientific proof of its activity can promote, in the future, a therapeutic alternative. The present study analyzed the chemical constitution of the dry crude extract (EBS) and hexane (FHX), dichloromethane (FDM), ethyl acetate (AED) and methanolic (FME) fractions of the species by high-performance liquid chromatography (HPLC) with tandem mass spectrometric - LC/MS, as well as its antioxidant activities by bioautography and cytotoxic assays, in vitro, against HELA, HEP-2 and VERO tumor cell lines. The samples showed antioxidant activity, being the fractions FDM and AED results more relevant. The EBS and fractions demonstrated cytotoxicity on all cell lines, however the FDM fraction had greater cytotoxic activity against tumor cells. In the LC/MS analyzes, were detected phenolic compounds and suggestive characteristics of chicoric acid presence through m/z = 148, as in the UV spectrum. These results demonstrate that this species has antioxidant activity and suggest its cytotoxicity against tumor cells, being a promising species for future studies.
Acesso aberto (Open Access)
Investigação fitoquímica e das atividades antioxidante e antiparasitária do extrato e frações de Aspidosperma excelsum Benth
(Universidade Federal do Pará, 2013-09-30) NASCIMENTO, Myrth Soares do; VASCONCELOS, Flávio de; http://lattes.cnpq.br/3695753129639448; BARBOSA, Wagner Luiz Ramos; http://lattes.cnpq.br/1372405563294070
Neglected diseases are diseases that affect a large number of people around the world. These include Chagas disease, leishmaniasis and malaria, whose therapy used, in addition to reduced presents problems that hinder their treatment and show the need to search for new therapeutic options. Aspidosperma excelsum (Apocynaceae), popularly known as carapanaúba, is used in the popular herbal medicine for the treatment of malaria. Its chemical constitution and antiparasitic activity of other species of genus suggests its antiparasitic potential. To investigate their chemical constitution and possible biological activities, the lyophilized extract, obtained from barks of specie, and their alkaloidic fractions were analyzed by chromatographic techniques and evaluated for antioxidant and antiparasitic activity against Leishmania ssp., Trypanossoma cruzi e Plasmodium falciparum. The HPLC analyses showed peaks highly correlated to yohimbine in the tincture and in its alkaloidic fractions: FAlk7, FAlk10 and FAlk14. All the samples were active against L. chagasi and FAlk1, FAlk4 and FAlk7 show IC50 values lower than Amphotericin B against L. braziliensis. Fractions FAlk1 and FAlk4 were also active on P. falciparum, showing high selectivity to the parasite. Evaluation of antioxidant activity revealed important capacity of samples in capturing free radicals, characterizing them as antioxidants.
Acesso aberto (Open Access)
Planejamento, síntese e aplicações de derivados naftosalicílicos como antioxidantes
(Universidade Federal do Pará, 2017-08-30) BARROS, Valéria Araújo; BORGES, Rosivaldo dos Santos; http://lattes.cnpq.br/4783661132100859; https://orcid.org/ 0000-0003-4072-7573
Salicylate derivatives are successfully applied as analgesics, antipyretics, anti-inflammatories and in cancer prevention, especially rectal colon. They reduce the risks of many diseases associated with elderly. However, adverse effects related to gastrointestinal events are always associated to its main constituent acetylsalicylic acid. These aspects are linked to their chemical stability and affinity for some biological receptors. The aims of this work are the design, synthesis and applications of naphthalene-salicylic derivatives as antioxidants. Thus, a theoretical study of the studied compounds was carried out. Calculations of electronic properties such as frontier orbitals HOMO-LUMO, ionization potential (IP), bond dissociation energy of phenolic moiety (BDEOH), and spin density contributions were performed by using density functional theory (DFT) at the B3LYP/6-31G (d, p) level of theory on Gaussview and Gaussian computational packages. Some of these compounds were synthesized by using classical methods. The theoretical results showed that both additional hydroxyl or substitution on benzene ring for naphthalene increase the antioxidant capacity in the same values with small dissimilarities among acid, ester, and amide derivatives. A synergistic effect was observed when both are used together, producing the most potent molecules. In addition, spin density calculations indicated a regioselective pathway can be gotten from monohydroxylic derivatives, with high possibility of in vivo generating of dihydroxy derivatives mainly at the para position relative to the phenolic group, through enzymatic or non-enzymatic reactions. Finally, the replacement of the naphthalene ring instead of the benzene ring increases both reactivity and chemical stability for the quinone-type intermediates, explaining how these compounds will play a role in the preventive mechanisms and way treatment of cancer. Anti cancer and anti-inflammatory activities are being performed for some of the synthesized compounds.
Acesso aberto (Open Access)
Planejamento, síntese e avaliação dos derivados da edaravona quanto à atividade antioxidante
(Universidade Federal do Pará, 2018-03-28) AIRES, Wanessa Castilho; OLIVEIRA, Karen Renata Matos; http://lattes.cnpq.br/3032008039259369; BORGES, Rosivaldo dos Santos; http://lattes.cnpq.br/4783661132100859; https://orcid.org/ 0000-0003-4072-7573
Edaravone is a commercial drug released on the Japanese Market, indicated in the treatment and prevention of ischemic stroke. Its action is due to its scavenger properties of free radical released in the ischemia. However, its use may lead to a kidney toxic effect. Therefore, in this work, a new bioisostere derivative from Edaravone was proposed, by the change of a pyrazolone ring for an indolone. Antioxidant properties was determined through computational methods. Calculations were undertaken in the software Gaussian, through the B3LYP method, with the set of bases 6-31G (d, p). Antioxidant activity was predicted from HOMO, LUMO, Gap, Ionization potential (IP) and Bond dissociation energy (BDE). Results indicate analogous compounds showed higher ClogP values compared to Edaravone, which means higher facility to pass through biological barriers, with higher liposoluble properties. Edaravone derivative, called Imidazone, also showed higher antioxidant potential than Edaravone. Methyl group in second position of heterocyclic ring was essential to more stable resonance structures formation to semiquinone form. All new derivatives proposed were extremely promising with antioxidant capacity superior to Edaravone.
Acesso aberto (Open Access)
Principais compostos bioativos e capacidade antioxidante da polpa do camu-camu (Myrciaria dubia) em diferentes estádios de maturação
(Universidade Federal do Pará, 2014-06-25) OLIVEIRA, Thaise Cristine de Souza; MATTIETTO, Rafaella de Andrade; http://lattes.cnpq.br/7832266671782588; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
This study aimed to determine physical and physico-chemical characteristics, bioactive compounds and antioxidant capacity from camu-camu pulp of three different progenies, came from Active Germplasm Bank of camucamuzeiro, at Embrapa Amazônia Oriental, in three ripening stages. Over the ripening, the mass and the diameters varied (p ≤ 0.05) just for progeny 44 and the pulp yield increased for all the progenies, with results over 50% in the ripe stage. The ripening stage didn’t show effects in the moisture and ashes content and also pH for progeny 38; ashes for progeny 44 and fat and insoluble fibers for progeny 17. The others results varied with the ripening, but, with different behaviors to each progeny, except for the total sugar, soluble solids contents and the SS/TTA ratio, which showed a tendency to increase, and the total titratable acidity decreased in all the progenies. Overall, a higher level of vitamins C were obtained in the green stage, with a first step of degradation, as it reached the semi-ripe stage, followed by a synthesis step until the end of the ripening stage, except for the progeny 38, which showed a reduction. As for the phenolic compounds, during the ripening stage, the three progenies were characterized for synthesis and degradation processes of the total phenolic compounds; the total flavanols decreased; the flavonols content had a distinct behavior in each progeny, with an increasing in the progenies 17 and 38, and a decreasing in the progeny 44; due to a limitation of the method used to determine small quantities, It was possible to quantify anthocyanins only for progenies 17 and 44 in the ripening stage. The antioxidant capacity, determinated through the methods TEAC and DPPH, decreased in all the progenies. Besides the significant effects of the ripening stage, the results showed that the genetic variability of camu-camu influenced significantly the physical characteristics of the fruits and the continents of all compounds studied, and still the antioxidant capacity obtained through the methods mentioned.
Acesso aberto (Open Access)
Principais compostos bioativos e capacidade antioxidante no epicarpo do camu-camu (Myrciaria dubia) em função da maturação
(Universidade Federal do Pará, 2014-06-25) SOUZA, Aline Ozana de; MATTIETTO, Rafaella de Andrade; http://lattes.cnpq.br/7832266671782588; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
The presence of bioactive compounds suffers greatly influenced by environmental and genetic factors, and behave differently in each part of the plant. However, there are few studies which deal these aspects of camu-camu. Thus, this study aimed to analyze the physical, physico-chemical composition, the main bioactive compounds and antioxidant capacity of camu-camu bark, depending on the stage of ripeness in fruits of different genotypes from plant matrices Bank Active Germplasm Camucamuzeiro of Embrapa Eastern Amazon. Fruits of three genotypes, selected at random in three maturity stages were collected. Results were expressed on a dry basis and analyzed by Analysis of Variance, Comparison Test Tukey's and Pearson's Correlation Coefficient, with a confidence interval of 95%. For physico-chemical analysis, there was a different one for each progeny, depending on maturity, except that the carbohydrate content increased in all progenies behavior. For vitamin C, the progenies 38 and 44 showed a high content of ascorbic acid, comparing the green and ripe stages, and 17 progeny showed a decrease during maturation; the highest content of vitamin C has been found in 44 progeny, ripe stage (24,02 g/100g). All progenies showed an increase in the content of total phenolics and anthocyanins throughout maturation, with the highest values were demonstrated by progeny 17 (3298,98 AGE/100g mg) and 44 (165,91 mg/100g) respectively. Flavonols and carotenoids showed a distinct and statistically different behavior in each progeny, with the highest content of flavonols was found in 17 progeny in the green stage (343,63 mg QE/100g) and carotenoids in 44 progeny, ripe stage (105,88 mg/100g). Regarding the antioxidant activity based on the DPPH method, the progenies 38 and 44 showed the same behavior throughout maturation, with higher antioxidant activity half ripe and smallest stage in green, with the highest antioxidant activity was found in 17 progeny in the ripe stage (38,95 g fruit/g). Already by ABTS method, the antioxidant activity was statistically different for all progenies and in all stages of maturation, higher value submitted by 44 progeny at maturity (170,63 μM trolox/g). Evaluating the relationship between bioactive compounds and antioxidant activity, the 17 progeny won more statistically significant correlations. It can be concluded that various factors cause differences in the synthesis of various compounds during fruit ripening of camucamuzeiro.
Acesso aberto (Open Access)
O uso de compostos fenólicos na prevenção da doença de parkinson: análise bibliométrica e crítica dos 100 artigos mais citados da Web of Science e avaliação neuroprotetora do açaí (euterpe oleracea) em ratos wistar
(Universidade Federal do Pará, 2022-12) SANTOS JUNIOR, José Messias dos; LIMA, Rafael Rodrigues; http://lattes.cnpq.br/3512648574555468; HTTPS://ORCID.ORG/0000-0003-1486-4013; ROGEZ, Hervé Louis Ghislain; http://lattes.cnpq.br/5202118426597590; https://orcid.org/0000-0001-8925-8881
Parkinson's disease is characterized by the death of dopaminergic neurons with both motor and non-motor symptoms. The current treatment available does not prevent the progression of the disease and, therefore, new alternatives have been sought for its prevention. Phenolic compounds that are present in foods and beverages of plant origin have bioactivities including antioxidant and anti-inflammatory activity that may contribute to neuroprotection. The general objective of this thesis is to evaluate bibliometric parameters and experimental designs of the 100 most cited articles from WoS-CC on the use of phenolic compounds in Parkinson's disease and to carry out an in vivo laboratory study using Wistar rats exposed to açaí for 15 days before induction of Parkinson's disease-like symptoms through 6-hydroxydopamine. The 100 most cited articles in WoS-CC are predominantly from the Asian continent and China, EGCG and oxidative stress being the most evaluated compound and therapeutic target among the 100 studies. In vitro and in vivo laboratory studies represent approximately 70% of the list. The results demonstrated among the 100 articles are due to concentrations and administration routes that do not resemble consumption through the diet. Pre-treatment with açaí increased GSH levels and decreased MDA levels, in addition to preventing damage to spontaneous locomotion. The results suggest the neuroprotective potential of açaí related to its composition of phenolic compounds.