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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Isolation And Characterisation Of Antioxidant Compounds In Yellow Rose Root Extracts

Kyejjusa, Yusuf 01 June 2009 (has links) (PDF)
A phytochemical investigation on methanolic extract of roots of yellow rose led to the isolation of a catechin gallate. The crude extract first underwent fractionation using petroleum ether, chloroform, ethylacetate, butanol with water as solvents in their respective order. The emerging solvent fractions were subjected to further separation using lipophilic sephadex (LH-20), and silica gel column chromatography to isolate pure compounds. Analytical thin layer chromatography (TLC) was used to confirm the presence of a catechin in butanol fraction. Purified catechin compound was subjected to 2,2-diphenyl-1-picrylhydrazyl (DPPH) experiment to determine its Radical Scavenging Capacity, which was found quite promising. Chemical structure of purified compound was established by using Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) experiments.
32

Use of antioxidant activity and flavonoid levels to assess the quality of commercially available solid dose Sutherlandia frutescens products

Hess, Meggan Sade January 2010 (has links)
The overall aims of this project were to assess the pharmaceutical quality and consistency of commercially available solid dose Sutherlandia frutescens containing products (viz. tablets & capsules) by exploring the use of monitoring the pharmaceutical presentation, flavonoid profile and antioxidant activity levels and to develop/or adapt methods and specifications that may be used for the quality control of such products.Stability tests were conducted on all of the selected SCP. The products were stored under elevated temperatures and environmental humidity conditions and total phenol, antioxidant and chromatographic analysis was conducted on these samples. Samples of each of the SCP were hydrolyzed using HCL and then analyzed using HPLC to test the stability of the flavonoids present in each product. The SCP investigated in this study physically appeared to be of quite good “pharmaceutical” quality, but generally lacked information on the date of manufacture and lacked package inserts, or when these were present they contained insufficient information.Based on the results obtained, it is recommended that, the manufacturers of SCP pay more attention to the information provided on the package inserts and the storage conditions for their products. Further the levels of antioxidant activity, total phenols and flavonoid (sutherlandins A to D) be used as specifications to control the quality of commercially available solid dose Sutherlandia frutescens containing preparations on an individual basis.
33

Sledování antioxidační aktivity u laboratorního potkana při zkrmování barevné pšenice Konini

Holeksová, Veronika January 2015 (has links)
In the experiment, we observed how it affects feeding colored wheat grains with purple color on the antioxidant activity in the liver and in the blood of rats. For the experiment, we used 64 male rats Wistar albino four to six weeks. The experiment was performed four weeks. Experimental group (n=32) rats fed the only color wheat Konini. Purple wheat Konini (14.01 mg/g of anthocyanins). The control group (n=32) are fed conventional wheat Bohemia mixed with gluten to supplement the crude protein content as Konina (16%). During the experiment, we looked at three day intervals additions and weighed daily feed consumption. Antioxidant activity was measured by methods DPPH, FR, FRAP and ABTS. Results of measurement of antioxidant activity in the liver appeared inconclusive for all the methods. Only the results of the FR and FRAP with blood appeared conclusive. At control FR mg/l 297,35+-23,94 and Konini 215,57+-12.16 .FRAP mg/l control 28,78+-1,35 and 23.86 +-1.28 Konin. Other methods for blood came out inconclusive as well as in the liver. We found that liver weight in rats fed wheat Konin was 7% lower than in control rats. The results were processed using a statistical method ANOVA Scheffe test.
34

Použití polyvinylpolypyrrolidonu a možnosti jeho regenerace v nápojovém průmyslu

Šajtarová, Pavla January 2016 (has links)
This diploma thesis is focused on the topic The use of polyvinylpolypyrrolidone and possibilities of its regeneration in the beverage industry. The thesis was written in years 2015/2016 at the Department of Post-Harvest Technology of Horticultural Products, Faculty of Horticulture at Mendel University in Brno. The theoretical part deals with the polyphenolics compounds in wine, antioxidant capacity and wine defects related to polyphenols. The last chapter offers multiple methods of removing defects, where the highest priority is given to the clarifier PVPP. The experimental part is aimed at the regeneration of single used PVPP with four different ways and the determination of its efficiency throughout suitable analyses after its reuse in the wine. The resulting data are statistically processed and shown in the graphs.
35

Vliv oxidu siřičitého na vybrané kvalitatívní parametry vína

Varmuža, Radek January 2016 (has links)
This thesis dealing with The influence of sulfur dioxide on on qualitative parameters of the wines was developer between 2014/2016 at the Department of Post Harvest Technology of Horticultural Products, Faculty of Horticulture, Mendel University in Brno. In this thesis was studied influence of sulfur dioxide on total polyphenols, which was measured by Folin-Ciocalteu and antioxidant capacity, which was measured by FRAP and DPPH. For this experiment were chosen two wines. The white wine was Rulandské bílé and the red wine was Svatovavřinecké. Doses of sulfur dioxide were applied at 0 mg/l, 25 mg/l, 50 mg/l, 75 mg/l, 100 mg/l. These doses are used in winemaking. Was found, that sulfur dioxide added to wine influence measured values of polyphenols and antioxidant capacity measured by FRAP and DPPH. Also was found, that system FRAP is more affected by sulfur dioxide, than system DPPH.
36

ULTRASONIC APPLICATIONS- PHYTOCHEMICAL ANALYSES OF SOME MEDICINAL NATURAL PRODUCTS IN FOOD PLANTS

Altemimi, Ammar Badran 01 May 2016 (has links)
There are concerns about using synthetic phenolic antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) as food additives because negative effects to human health have been reported. thus, a replacement of these synthetics by antioxidant extractions from various foods has been proposed. By the generation of more than eight thousand different phenolics, fruits and vegetables are the prime sources of natural antioxidants. The consumption of fruits and vegetables has been strongly linked with several health benefits, a result of their medicinal properties and high nutritional value. Antioxidants control and reduce the oxidative damage in foods by delaying or inhibiting oxidation caused by reactive oxygen species (ROHs); ultimately increasing the shelf-life and quality of these foods.Beta-carotene, ascorbic acid, and many phenolics play dynamic roles in delaying aging, reducing inflammations, and preventing certain cancers. Increasing the consumption of fruits and vegetables has been recommended by many agencies and health care systems. In order to extract, measure, and identify bioactive compounds from a wide variety of fruits and vegetables, researchers use many different techniques and methods. Ultrasonic assisted technique (UAE) is known to be one of the easiest extraction techniques because it uses common laboratory equipment such as ultrasonic baths and probes. In this technique, a smashed sample is mixed with the suitable solvent and placed into the ultrasonic bath while temperature and extraction time are controlled. Five experiments were conducted to study the effects of different ultrasonic parameters on the polyphenol and antioxidant content and antimicrobial activity of extracts from plants grown in southern Illinois. In the first experiment, ultrasonic treatments at different frequencies,temperatures, power levels, and exposure times were compared for their effects on the yield of total phenolics, total flavonoids and antioxidant activities of spinach extracts. The best conditions for extraction judged by yields were an ultrasonic frequency of 37 kHz, extraction time of 30 min, reaction temperature of 400C, and ultrasonic power of 50%. The mean yield (mg/100g), total phenolics (mg gallic acid equivalence/ g DW), flavonoids (mg/g DW), % DPPH free radical scavenging activity, and % ferric reducing antioxidant power were all high (64.88±21.84, 33.96±11.30, 27.37±11.85 , 64.18±16.69 and 70.25 ±9.68). In the second experiment, the study was designed to optimize ultrasonic-assisted extraction of lutein and β-carotene from spinach. Further, the identities and purity of the natural products in the TLC spots were assayed using matrix-assisted laser desorption/ionization time-off-light mass spectrometry (MALDI-TOF MS) analysis. The optimal UAE settings for output of lutein and β-carotene simultaneously from spinach extracts were an extraction temperature of 40 °C, extraction power of 40% (28 W/cm3) and extraction time of 16 min. UAE assisted extraction of carotenes from spinach can provide a source of lutein and β-carotene for the dietary supplement industry. In the third study, investigations of the effects of extraction parameters for UAE on antioxidant activity of peach and pumpkin extracts; and studying the chemical structures of samples before and after processing by Fourier transformed infrared spectroscopy were made. The optimal conditions for peach extracts were an extraction temperature of 41.53 ̊C, power of 43.99 % and time of 27.86 min for total phenolics. The optimal conditions for extractions of total phenolics from pumpkins were inferred to be a temperature of 41.45 ̊C, a power of 44.60 % and a time of 25.67 min. In the fourth study, TLC followed by Quantity-OneTM (Biorad) image analysis was used as a simple and rapid method for identification and quantification of compounds in complex mixtures. The results were consistent under optimal conditions among the experimental values and their predicted values. The MALDI-TOF MS technique was also applied for result confirmation. In the last experiments, UAE and Box-Wilson design were applied to optimize the extraction of antimicrobial activities from spinach extracts and to test their antimicrobial activities on both Gram-negative and Gram-positive bacteria. The spinach extracts exhibited antimicrobial activities against both bacterial pathogens with MICs in the 60-100 mg.ml-1 range. SEM showed that cells of the treated bacterial strains were damaged and showed structural defects compared to the controls. RAPD analysis of genomic DNA showed that the number and sizes of amplicons were decreased for the treated pathogens compared with non-treated strains.
37

Croton nummularis Baill. (Euphorbiaceae): composição química, atividade biológica, antioxidante e toxicidade preliminar dos óleos essenciais

BASTO, Sarah Romini de Lima 07 August 2013 (has links)
Submitted by Eduardo Barros de Almeida Silva (eduardo.philippe@ufpe.br) on 2015-04-14T14:38:14Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO Sarah Romini de Lima.pdf: 1450315 bytes, checksum: 6c41aa09d1754d537242ef3fb4fb69ae (MD5) / Made available in DSpace on 2015-04-14T14:38:14Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO Sarah Romini de Lima.pdf: 1450315 bytes, checksum: 6c41aa09d1754d537242ef3fb4fb69ae (MD5) Previous issue date: 2013-08-07 / CAPES;FACEPE / O gênero Croton L. pertence à família Euphorbiaceae. O Brasil é um dos principais centros de diversidade do gênero. Este gênero é muitas vezes usado na medicina popular para aliviar a dor, para tratamento de câncer, diabetes, inflamação e outros. Dado o potencial botânico da Caatinga e a necessidade de encontrar novos compostos capazes de controlar a ação de microorganismos, procurou-se realizar um trabalho que permita um maior conhecimento das espécies na região, em especial a espécie de Croton nummularius Baill. As folhas e ramos de C. nummularius forneceram um rendimento de óleo de 0,72% e 0,36%, respectivamente. Os principais compostos encontrados no óleo de folhas foram espatulenol (27,73%) e beta-cariofileno (14,37%). O óleo do ramo foi dominado por isolongifolene (35,60%), nerolidol (12,13%) e beta-cariofileno (11,76%). O óleo essencial de folhas de C. nummularius mostrou uma elevada atividade larvicida (CL50, 2,34 ± 0,01 ug.mL-1). Os resultados demonstraram que o óleo essencial das folhas inibiram o crescimento de todas as bactérias gram-positivas e gram-negativas (Enterococcus faecalis, Escherichia coli, Pseudomonas aerugiosa, Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Klebsiella pneumoniae), e somente não apresentou ação bactericida contra Streptococcus pyogenes. Na atividade antioxidante o óleo essencial das folhas de C. nummularius, reduziu aproximadamente 76,16% a 5 mg / ml dos radicais livres DPPH.
38

Purificação, caracterização e atividades biológicas de proteína de folhas de Indigofera suffruticosa

Pereira, Dewson Rocha 29 April 2013 (has links)
Submitted by Eduardo Barros de Almeida Silva (eduardo.philippe@ufpe.br) on 2015-04-17T12:11:54Z No. of bitstreams: 2 Tese Dewson Pereira.pdf: 2434638 bytes, checksum: 7654476b56a86b806d79d80bc97a8fbd (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-04-17T12:11:54Z (GMT). No. of bitstreams: 2 Tese Dewson Pereira.pdf: 2434638 bytes, checksum: 7654476b56a86b806d79d80bc97a8fbd (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2013-04-29 / Lectinas são proteínas de origem não imune que se ligam de forma reversível e não covalente a carboidratos e glicoconjugados. A espécie Indigofera suffruticosa Mill., encontrada na região do Semi-Árido Pernambucano, é utilizada popularmente como antiespasmódico, sedativo, diurético e purgativo. O objetivo deste estudo foi isolar, caracterizar e avaliar o potencial biológico de uma proteína de I. suffruticosa. Uma proteína de folhas de I. suffruticosa foi obtida por cromatografia de afinidade em coluna de quitina e demonstrou ser uma glicoproteína ácida com massa molecular de 35 kDa e 3,6 % de carboidratos neutros. Esta proteína apresentou maior atividade hemaglutinante específica para eritrócitos humanos do tipo A e foi inibida por glicoproteínas e monossacarídeos, demonstrando ser uma lectina que foi denominada IsuLL. Sua atividade hemaglutinante foi estável na faixa de pH entre 6,5 a 7,0, termoresistente e não foi alterada por cations divalentes. A espectroscopia de infravermelho revelou que IsuLL possui um maior percentual de estruturas do tipo folhas . Espectroscopia de fluorescência intrínseca e extrínseca da estrutura molecular de IsuLL demonstrou a presença de resíduos triptófano e tirosina expostos na superfície da molécula e regiões hidrofóbicas parcialmente internalizadas. A estrutura de IsuLL revelou alta estabilidade térmica (T=200 ºC), avaliada pela curva de Termogravimetria. Esta lectina demonstrou atividade antioxidante (52 %) pela redução do radical DPPH . IsuLL foi tóxica para larvas de Artemia salina com CL50 de 207.87±2 μg/mL, indicando toxicidade ambiental moderada e não reduziu, significativamente, a proliferação celular das linhagens humanas de nasofaringe (HeLa) e leucêmicas (KG1). IsuLL inibiu o crescimento de Candida albicans (MIC=64 μg mL-1), C. tropicalis (MIC=16 μg.ml-1) e C. krusei (MIC=8 μg mL-1) e Staphylococcus aureus (MIC=15 μg mL-1). O estudo do efeito de IsuLL sobre S. aureus revelou modificação na parede celular, utilizando técnicas de Microscopia Eletrônica de Transmissão, captação do cristal violeta e liberação de material genético. A associação de IsuLL com antibióticos (ampicilina e cifoxitina) foi sinérgica contra S. aureus. Os resultados indicam que IsuLL, isolada de folhas de I. suffruticosa, é uma nova lectina de estrutura estável com atividade antimicrobiana e antioxidante, de potencial aplicação biotecnológica.
39

Avaliação da composição e da capacidade antioxidante "in vivo" e "in vitro"de antocianinas da casca de jabuticaba (Myrciaria jaboticaba (Vell.) Berg) liofilizada em ratos Wistar / Evaluation of composition and antioxidant capacity in vivo and in vitro anthocyanins in freeze-dried jaboticaba peel (Myrciaria jaboticaba (Vell.) Berg) in rats

Leite, Alice Vieira 16 August 2018 (has links)
Orientador: Mário Roberto Maróstica Júnior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-16T13:28:38Z (GMT). No. of bitstreams: 1 Leite_AliceVieira_M.pdf: 971111 bytes, checksum: 075888bf78f40ee6ae18cdf0e3fb131a (MD5) Previous issue date: 2010 / Resumo: O objetivo do presente estudo foi avaliar a produção de casca de jabuticaba em pó, sua composição de antocianinas e efeito antioxidante em animais de laboratório. Muitas frutas tropicais são ricas em antocianinas e existem poucos dados disponíveis sobre a caracterização e quantificação destas antocianinas. A identificação e quantificação de antocianinas de casca de jabuticaba liofilizada foram realizadas por HPLC-PDA e HPLC-ESI-MS/MS e revelaram a presença de dois compostos, delfinidina-3-glicosídeo e cianidina-3- glicosídeo (635,3 e 1964 mg/100 de peso seco), respectivamente. Para as análises do potencial antioxidante foram utilizados os ensaios de ORAC, DPPH e ABTS. Para estes ensaios foram encontrados os seguintes valores, respectivamente, 25514,25±3037,24 YMTEAC.g-1, 45,38 Yg.ml-1, 9457,74±54,29 YMTEAC.g-1. Foram quantificados também os fenólicos totais por Folin-Ciocalteau, e encontrado 556,28±20,37 gGAEb.kg-1 .Neste estudo, a casca de jabuticaba liofilizada mostrou uma grande capacidade antioxidante comprovada por todos os métodos antioxidantes analisados, pela quantidade de compostos fenólicos encontrada e principalmente pela concentração de cianidina-3-glicosídeo e delfinidina-3- glicosídeo. Diante dos dados descritos acima, o efeito antioxidante da ingestão de pó casca de jabuticaba liofilizada no plasma de ratos foi investigado em dois experimentos. No primeiro foi realizado um teste de cinética de absorção, no qual trinta e cinco ratos machos, divididos em 5 grupos, receberam por gavagem 7 mg de antocianinas/ 100 g de peso. A coleta de sangue foi realizada nos tempos 0, 30, 60 e 120 minutos. O potencial antioxidante foi quantificado no plasma por ORAC e TEAC. Neste experimento não ocorreu diferença significativa no potencial antioxidante plasmático quando comparados os diversos tempos. No segundo experimento, 40 ratos machos foram divididos em 4 grupos que consumiram, respectivamente, 0, 1, 2 e 4% de pó de casca de jabuticaba liofilizada acrescido a dieta. Foi observado um aumento no potencial antioxidante plasmático (1.7 vezes pelo método de TEAC e 1.3 vezes por ORAC), porém a concentração de 4% não apresentou efeito antioxidante. A partir dos resultados do potencial antioxidante in vivo, e diante do fato de que a ingestão de uma dieta rica em antioxidantes e com pouca quantidade de gorduras pode reduzir o risco de obesidade e resistência à insulina, investigou-se o efeito da casca de jabuticaba liofilizada sobre as concentrações plasmáticas de glicose, frações lipídicas, aspartato aminotransferase e alanina aminotrasferase em ratos Wistar machos adultos. Os animais foram distribuídos nos seguintes grupos: G0, o grupo controle e G1, G2 e G4, os grupos que receberam 1, 2 e 4%, respectivamente, do pó de casca de jabuticaba liofilizada adicionado à dieta AIN-93M. A suplementação reduziu as concentrações de glicose nos grupos G1 e G2, porém no grupo G3 esse efeito não foi encontrado. O colesterol total sofreu redução para os animais tratados com 1% de cascas de jabuticabas em relação ao grupo controle, mas os animais tratados com 2 e 4% de cascas de jabuticabas sofreram aumento no colesterol total e da fração LDL-colesterol, porém, o valor para colesterol total apresenta-se dentro da faixa normal para ratos Wistar. Os triacilgliceróis e a fração HDL-colesterol não sofreram alterações significativas. Os resultados indicam um possível benefício da suplementação da casca de jabuticaba na redução da glicemia plasmática, dos níveis de LDL e colesterol total e a possível existência de uma dose recomendada / Abstract: The objective of this study was to evaluate the antioxidant effects of anthocyanin and the antioxidant effects of peel jabuticaba powder in laboratory animals. Many tropical fruits are rich in anthocyanins, but there are few data available on the characterization and quantification of these anthocyanins. The identification and quantification of anthocyanins from bark jabuticaba was performed by HPLC-PDA and LC-ESI-MS/MS Q-TOF. The analysis revealed the presence of two compounds, delphinidin-3-glucoside and cyanidin-3-glucoside (635, 3 and 1964 mg/100 dry weight, respectively). ORAC, DPPH and ABTS methods were used for antioxidant analysis and the results were, 25514,24±3037,24 µMTEAC.g-1, 45.38 Yg.ml-1, 9457,74±54,29 µMTEAC.g-1, respectively. The total phenolics (Folin-Ciocalteau method) revealed that the jabuticaba powder contained 556,28±20,37 gGAEb.kg-1. In this study, freezedried peel jabuticaba showed great antioxidant proven by all methods antioxidants tested. The effects of the ingestion of jabuticaba peel in the antioxidant capacity of plasma of rats was investigated in two 'in vivo¿ experiments. In the first test, the absorption kinetics were evaluated. The male rats were divided into 5 groups received, by gavage, 7 mg anthocyanins / 100 g of body weight. Blood collection was performed at 0, 30, 60 and 120 minutes. The antioxidant potential was quantified in plasma by ORAC and TEAC. In this experiment there was no significant difference in plasma antioxidant potential when comparing the different times. In the second experiment, 40 rats were divided into 4 groups that consumed, respectively, 0, 1, 2 and 4% powdered peel jabuticaba lyophilized plus diet. We observed an increase in plasma antioxidant potential (1.7 times by the method of TEAC and ORAC by 1.3 4 times), but the concentration of 4% had no antioxidant effect. We investigated the effect of freeze-dried peel jabuticaba on plasma glucose, lipid fractions, aminotransferase and aspartate aminotransferase alanian in adult male Wistar rats. The animals assigned to groups G0, the control group, G1, G2 and G4 groups receiving 1, 2 and 4%, respectively, of freeze-dried peel jabuticaba added to the AIN-93M diet. Supplementation reduced the concentration of glucose in G1 and G2, but in G4 this effect was not found. Total cholesterol was reduced in animals treated with 1% bark jabuticabas in the control group, but animals treated with 2 and 4% experienced an increase in total cholesterol and LDL cholesterol, but the value for cholesterol total amount is within the normal range for rats. Triglycerides and HDL-cholesterol did not change significantly. The results indicate the possible benefit of supplementing with bark jabuticaba in reducing plasma glucose, LDL cholesterol and total cholesterol and the possible existence of a dose / Mestrado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Mestre em Alimentos e Nutrição
40

Atividade antioxidante de plantas medicinais da caatinga e mata atlântica: aspectos etnobotânicos e ecológicos

ARAÚJO, Thiago Antonio de Sousa 28 May 2012 (has links)
Submitted by Heitor Rapela Medeiros (heitor.rapela@ufpe.br) on 2015-03-04T14:01:02Z No. of bitstreams: 2 tese THIAGO ARAÚJO eletronica.pdf: 2759871 bytes, checksum: dd1dfa95aba3b0623e02381ab94779ed (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-04T14:01:02Z (GMT). No. of bitstreams: 2 tese THIAGO ARAÚJO eletronica.pdf: 2759871 bytes, checksum: dd1dfa95aba3b0623e02381ab94779ed (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2012-05-28 / FACEPE / A Caatinga e a Mata Atlântica são as principais fontes de plantas medicinais para povos que vivem no Nordeste do Brasil. Diversas plantas destes dos tipos vegetacionais são usados em doenças ou sintomas relacionados com o aumento do estresse oxidativo nas células. Com isso, nosso objetivo foi testar como dois diferentes tipos vegetacionais influenciam na seleção de plantas medicinais e de como amostras destas plantas se comportam em relação a atividade antioxidante, além de testar se a sazonalidade climática afeta tal atividade e os compostos fenólicos nas cascas de Anadenanthera colubrina e se esta mesma atividade e a concentração de taninos nas cascas de Spondias tuberosa variam de em relação ao local de coleta. Para tal, foram realizadas entrevistas semiestruturadas em duas comunidades em duas diferentes regiões do Nordeste do Brasil e selecionadas espécies medicinais relacionadas a doenças que envolvem estresse oxidativo para a avaliação da atividade antioxidante pelo método de DPPH e FIC. A identificação e quantificação de compostos fenólicos foram realizadas por meio de CLAE e a quantificação de taninos pelo método de difusão radial. Os dois tipos vegetacionais influenciam na seleção de plantas medicinais para doenças que envolvem doenças com estresse oxidativo, contudo não foram observadas diferenças na atividade antioxidante nas amostras selecionadas nas duas comunidades independente dos métodos antioxidantes. A atividade antioxidante e os principais compostos fenólicos das cascas de A. colubrina variaram pouco ao longo do ano, porém estas diferenças são, aparentemente, não relacionadas ao regime de chuva. Em relação aos dados de S. tuberosa, foi observado diferença na atividade antioxidante de amostras coletadas em diferentes locais de coleta, contudo não houve diferença em relação a concentração nos teores de taninos. Ambas as comunidades apesar de selecionarem plantas de modos diferentes, conhecem espécies com alta capacidade no sequestro de radicais livres e como quelantes do ion ferroso. Os efeitos ambientais que atuam nas duas áreas de coleta não afetam significativamente nas espécies analisadas, de modo conjunto, e os mecanismos de ação antioxidante agem de modo independente nestas espécies. O local de coleta, dentro de um mesmo tipo vegetacional, parece influenciar mais na atividade antioxidante do que a variação pluviométrica.

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