Chemical, enzymatic and cellular antioxidant activity studies of Agaricus blazei Murrill

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diuretic and hipotensive activity of aqueous extract of parsley seeds (Petroselinum sativum Hoffm.) in rats

A espécie vegetal, Petroselinum sativum Hoff, conhecida como salsa, é amplamente utilizada na medicina popular brasileira como diurético. O objetivo desse estudo é verificar se o uso brasileiro do extrato aquoso da salsa tem efeitos semelhantes com investigações que mostram o efeito diurético da P. sativum em ratos. MÉTODOS: 19 Ratos foram anestesiados e canulamos a traquéia, artéria carótida esquerda (para a medição da pressão arterial) e bexiga urinária (para coletar urina). Depois de 40 minutos para adaptação das condições cirúrgicas, ratos anestesiados foram administrados de acordo com seus grupos: controle (CON), administração oral com 1.0 mL de água filtrada, e grupo tratado (AE), administração oral com extrato aquoso de sementes de salsa 20% (AE). Urina foi coletada três vezes (de 30 em 30 minutos) e então esse material foi utilizado para determinações de sódio e potássio, para avaliar a quantidade excretada desses íons. Pressão arterial foi medida pelo manômetro de mercúrio por 9 vezes. Todos os dados foram estatisticamente avaliados. RESULTADOS E CONCLUSÃO: nos parâmetros anestesiados, o grupo CON não mostrou nenhuma diferença; mas o grupo AE mostrou um aumento do fluxo urinário e da quantidade excretada de sódio e potássio, e também uma diminuição da pressão arterial. Todos os parâmetros apresentaram essas modificações após 30 minutos de administração do AE (p<0,05). Esses resultados mostram que o tratamento com o AE leva a efeitos natriurético e hipotensor em ratos Wistar anestesiados, confirmando o uso da população brasileira dessa erva como diurético.

Isoflavones supplementation of a probiotic soy product: effects on quality characteristics and isoflavones profile

The aim of the present study was to investigate the effect of isofl avones supplementation of a fermented soy product on its sensory acceptance, physicochemical properties and probiotic cell viable count. Additionally we also investigated the ability of the mixed starter cultures (Enterococcus faecium CRL 183 and Lactobacillus helveticus 416) to modify the isofl avones profi le of soy product during the fermentation process. Three products were analysed: soy product fermented with E. faecium CRL 183 and L. helveticus 416, isofl avonessupplemented soy product (fermented with E. faecium CRL 183 and L. helveticus 416; 50mg/100g, Isofl avin®, Galena, Brazil) and unfermented soy product. A panel of judges evaluated the acceptability of the samples on a nine point structured hedonic scale. The chemical composition namely fat, protein, ash and total carbohydrate contents, pH, enumeration of viable Lactobacillus spp. and Enterococcus spp. and quantifi cation of isofl avones using HPLC were investigated. All determinations were conducted after 7 days storage at 10°C. The sensorial acceptance was reduced in the isofl avones-supplemented soy product, but this effect was not signifi cant compared to the sample without isofl avones addition. Chemical composition did not differ (p<0.05) among the samples. Cell viable counts were reduced and total fermentation time was longer in the isofl avonessupplemented soy product, suggesting that the isofl avone addition could inhibit the starter cultures. However, all the products may be considered probiotic since they exhibited lactic acid bacterial populations varying from 2.3 x 109 up to 1.22 x 1010 CFU/mL. Fermentation of soymilk did not change the isofl avones profi le. In conclusion, it was possible to obtain a fermented soy product containing a high isofl avones concentration, adequate sensory and chemical characteristics and lactic acid bacterial viability suffi ciently high to characterize the product as a probiotic. The mixed starter culture was not able to convert the glycoside isofl avones into aglycone or produce equol during the fermented soy product processing.

Atividade da fração enriquecida em fenólicos de Buchenavia tomentosa e de algumas substâncias isoladas antes e após encapsulação com beta-ciclodextrina em Candida albicans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Potencial do flavedo (epicarpo) de Citrus aurantifolia cv. Tahiti no controle do bolor verde e da antracnose em citros

O Brasil é considerado o maior produtor de citros e o maior exportador de suco de laranja. Doenças de pós-colheita representam uma grande perda para a citricultura, sendo que para a exportação de frutos são rígidas as exigências com relação a isenção de resíduos químicos nos mesmos. Patógenos de importância em pós-colheita de citros incluem o Penicillium digitatum, agente causal do bolor-verde e o Colletotrichum gloeosporioides, agente causal da antracnose. Dada a importância econômica que representam estas doenças dos frutos cítricos, tanto em termos de comprometimento da qualidade e dificuldade de controle, a busca de alternativas adicionais que possam viabilizar a capacidade produtiva e garantir a obtenção de frutos com excelentes padrões de qualidade torna-se imprescindível. Portanto, estudou-se os efeitos dos extratos aquosos do flavedo de Citrus aurantifolia var. Tahiti, Lentinula edodes, Agaricus subrufescens (syn. Agaricus brasiliensis), albedo de Citrus sinensis var. Valência e do ácido jasmônico no controle póscolheita do bolor verde e da antracnose e na indução de resistência em frutos de laranjeira Valência (Citrus sinensis). Foi possível observar que o extrato aquoso do flavedo (C. aurantifolia) apresentou efeito inibitório sobre os patógenos, quando tratados em pós-colheita, em função da redução dos sintomas e esporulação. Porém, os extratos de albedo (C. sinensis), L. edodes, A. subrufescens e o ácido jasmônico não apresentaram efeitos sobre P. digitatum e C. gloeosporioides.

Atividade antibacteriana de sementes de açaí (Euterpe oleracea Mart.)

O presente trabalho teve como objetivo avaliar a atividade antibacteriana de um extrato aquoso de sementes de açaí (Euterpe oleracea Mart.), proveniente do Brasil, em isolados clínicos. O extrato revelou atividade antibacteriana em todos os isolados clínicos testados com a exceção de Escherichia coli e de Klebsiella pneumoniae. Os melhores valores de CMIs (concentrações mínimas inibitórias) foram observados para Staphylococcus aureus resistente à meticilina (MRSA) (0,25 mg/mL), Staphylococcus aureus sensível à meticilina (MSSA), Enterococcus faecalis e Streptococcus agalactiae com um valor de 0,5 mg/mL. O extrato testado parece ser uma opção a explorar no combate de bactérias resistentes.

Aproveitamento de subproduto de maçã da indústria agroalimentar

Neste trabalho foi estudado um subproduto derivado da indústria agroalimentar produtora de sumo concentrado de maçã, conhecido por bagaço de maçã, com o objetivo de avaliar condições de extração de compostos fenólicos, o teor de compostos fenólicos totais, flavonóides e proantocianidinas e ainda a atividade antioxidante. Foram efetuadas extrações a partir do bagaço de maçã variando as condições de tempo, temperatura, razão massa:volume e solvente e os extratos obtidos avaliados quanto ao seu teor em compostos fenólicos totais pelo método FolinCiocalteu. O extrato aquoso do bagaço de maçã para uma temperatura de 100 ºC a um tempo de 2x4h e concentração de 50 mg/mL, apresentou o teor de compostos fenólicos mais elevado (9,37 mgEAG/g de bagaço de maçã, na base seca) em relação a todas as outras temperaturas, tempos de extração e solventes utilizados, como etanol (50% e 70%) e metanol. O doseamento de flavonóides totais baseou-se no método espetrofotométrico, usando o reagente cloreto de alumínio e a rutina como padrão. Os melhores resultados foram obtidos usando etanol (70%) como solvente à temperatura ambiente, cerca de 4,35 mgER/g. A amostra extraída com água apresentou valores bastante similares ao etanol, cerca de 4,27 mgER/g, usando uma temperatura de 100 ºC durante 2x4h. O conteúdo em proantocianidinas foi determinado pelo método 4-dimetilamino cinamaldeído (DMAC). O bagaço de maçã estudado demonstrou ser pobre no seu conteúdo de proantocianidinas, obtendo valores de 0,77 mgEEC/g. A atividade antioxidante do bagaço de maçã foi avaliada através de dois métodos distintos: 2,2-difenil-1-picril-hidrazilo (DPPH∙) e método do poder redutor (FRAP). O extrato aquoso obtido a 100 ºC a um tempo de 2x4h, demonstrou ser aquele com maior potencial, com uma capacidade antioxidante mais elevada que os restantes extratos, com valores de IC50 de 0,48 mg/mL e 0,65 mg/mL, para os métodos de DPPH∙ e FRAP, respetivamente.

Bacterias anaeróbias como fábricas celulares: produção de hidrogénio e butirato por clostridium sp.

Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz

Atividade antiofídica do decocto das folhas de jatropha gossypiifolia l. frente o veneno de bothrops jararaca

Antiophidic activity from decoct of Jatropha gossypiifolia L. leaves against Bothrops jararaca venom. Snakebites are a serious worldwide public health problem. In Latin America, about 90 % of accidents are attributed to snakes from Bothrops genus. Currently, the main available treatment is the antivenom serum therapy, which has some disadvantages such as inability to neutralize local effects, risk of immunological reactions, high cost and difficult access in some regions. In this context, the search for alternative therapies to treat snakebites is relevant. Jatropha gossypiifolia L., a medicinal plant popularly known in Brazil as “pinhão-roxo”, is very used in folk medicine as antiophidic. So, the aim of this study is to evaluate the antiophidic properties of this species against enzymatic and biological activities from Bothrops jararaca snake venom. The aqueous leaf extract of J. gossypiifolia was prepared by decoction. The inhibition studies were performed in vitro, by pre-incubation of a fixed amount of venom with different amounts of extract from J. gossypiifolia for 60 min at 37 °C, and in vivo, through oral or intraperitoneal treatment of animals, in different doses, 60 min before venom injection. The proteolytic activity upon azocasein was efficiently inhibited, indicating inhibitory action upon metalloproteinases (SVMPs) and/or serine proteases (SVSPs). The extract inhibited the fibrinogenolytic activity, which was also confirmed by zymography, where it was possible to observe that the extract preferentially inhibits fibrinogenolytic enzymes of 26 and 28 kDa. The coagulant activity upon fibrinogen and plasma were significantly inhibited, suggesting an inhibitory action upon thrombin-like enzymes (SVTLEs), as well as upon clotting factor activators toxins. The extract prolonged the activated partial thromboplastin time (aPTT), suggesting an inhibitory action toward not only to SVTLEs, but also against endogenous thrombin. The defibrinogenating activity in vivo was efficiently inhibited by the extract on oral route, confirming the previous results. The local hemorrhagic activity was also significantly inhibited by oral route, indicating an inhibitory action upon SVMPs. The phospholipase activity in vitro was not inhibited. Nevertheless, the edematogenic and myotoxic activities were efficiently inhibited, by oral and intraperitoneal route, which may indicate an inhibitory effect of the extract upon Lys49 phospholipase (PLA2) and/ or SVMPs, or also an anti-inflammatory action against endogenous chemical mediators. Regarding the possible action mechanism, was observed that the extract did not presented proteolytic activity, however, presented protein precipitating action. In addition, the extract showed significant antioxidant activity in different models, which could justify, at least partially, the antiophidic activity presented. The metal chelating action presented by extract could be correlated with SVMPs inhibition, once these enzymes are metal-dependent. The phytochemical analysis revealed the presence of sugars, alkaloids, flavonoids, tannins, terpenes and/or steroids and proteins, from which the flavonoids could be pointed as major compounds, based on chromatographic profile obtained by thin layer chromatography (TLC). In conclusion, the results demonstrate that the J. gossypiifolia leaves decoct present potential antiophidic activity, including action upon snakebite local effects, suggesting that this species may be used as a new source of bioactive molecules against bothropic venom.

Efeitos de fungicidas alternativos em folhas de Carthamus tinctorius L. (Asteraceae), potencial espécie para cultivo em agricultura familiar

The currently main development model on global society is driven by an economic rationality that endangers the environment and social justice. More and more, attention to this way of production and consumption is increasing, boosting research for sustainable development, with an environmental rationality that can harmonize nature preservation and welfare of all socioeconomic classes. One of the efforts on this sense is changing the sources supplying the energy demand, replacing fossil fuels for renewable and cleaner sources, such as biofuels. Carthamus tinctorius (safflower) is an oilseed crop with potential for biodiesel production, with good oil yield and chemical profile, allied to good adaptation to climates such like the northeastern semiarid lands of Brazil. With public policies fomentation, the use of this species may be an interesting alternative for family farming. In farming in general, the use of pesticides to prevent and combat diseases and plagues is common, which is not a sustainable practice. Thus, there are researched alternative, less dangerous substances. In this study, it was aimed to assess if neem (Azadirachta indica) leaf extract (20% m/v) and Bordeaux mixture (copper sulfate) have effects on safflower. It was also aimed to verify acceptance of farmers on safflower crop in Apodi, a municipality in Rio Grande do Norte state, Brazil, in view of it being localized in the aimed region for this crop cultivation. Besides that, understanding that the farmers’ knowledge and inclination to adopt the crop is fundamental for the introduction of this species and socioeconomic growth due to its exploration. In addition, a booklet with basic information on safflower was produced. In the field experiment, the fungicides were pulverized on plants cultivated in field experimental plots, with collection of leaf samples for analysis on anatomy, cuticle, and epicuticular wax morphology, the protective layer that interfaces with the surrounding ambient. In Apodi, forty-five farmers from Potiguar Cooperative of Apiculture and Sustainable Rural Development (COOPAPI) underwent semi-structured interviews, which also addressed their assessment on currently cultivated crops and perception of pesticide uses and sustainable alternatives. After comparing using analysis of variance, it was found that there was no difference between treatments in the experiment, as well as no anatomical or morphological modifications. Safflower acceptation among farmers was wide, with 84% of interviewees believing in a perspective of good incomes. The current scenario, comprised of low crop diversity, fragile in face of droughts and plagues, can partially explain this opinion. The booklet was effective in catching people attention for the species potential. There was wide acknowledgement on the importance of alternative pesticides, justified by health security. Based on the assessed parameter in the results of this research, the treatments here utilized may be recommended as fungicides for safflower. Given the crop susceptibility to fungi in heavy rainy period, it is advised that its potential introduction on the region shall be focused on semiarid areas.

Avaliação anti-inflamatória e antipeçonhenta das espécies Hancornia speciosa e Mimosa tenuiflora em modelos experimentais de inflamação e envenenamento induzidos por Bothrops jararaca e Tityus serrulatus

Accidents caused by venomous animals represents a significant and serious public health problem in certain regions of Brazil, as well as in other parts of the world by the frequency with which they occur and the mortality they cause. The use of plant extracts as an antidote for poisoning cases is an ancient practice used in many communities that have no access to antivenom. Medicinal plants represent an important source of obtaining bioactive compounds able to assist directly in the treatment of poisoning or indirectly supplementing serum therapy currently used. The aim of this study was to evaluate the effect of extracts, fractions and isolated compounds from M. tenuiflora and H. speciosa in the inflammatory process induced by carrageenan and the venom of B. jararaca and T. serrulatus. The results showed that both M. tenuiflora and H. speciosa were capable of inhibiting cell migration and cytokines levels in peritonitis induced by carrageenin and venom of T. serrulatus. In poisoning by B. jararaca model, mice treated with the plants in studies decreased the leukocyte influx into the peritoneal cavity. Finally the M. tenuiflora and H. speciosa had antiphlogistic activity, reducing edema formation and exerted inhibitory action of leukocyte migration in local inflammation induced by the venom of B. jararaca. Through of Thin Layer Chromatography (TLC) analysis was possible identified the presence of flavonoids ,saponins and/or terpenes in aqueous extract of M. tenuiflora. By High Performance Liquid Chromatography analysis, it was possible to identify the presence of rutin and chlorogenic acid in aqueous extract of H. speciosa. We conclude that the administration of extracts, fractions and isolated compounds of H. speciosa and M. tenuiflora resulted in inhibition of the inflammatory process in different experimental models. This study demonstrates for the first time the effect of M. tenuiflora and H. speciosa in inhibition of the inflammation caused by B. jararaca and T. serrulatus venom.

Avaliação de duas variedades de Passiflora edulis sobre as respostas comportamentais de camundongos e um possível mecanismo de ação

The medicinal plants constitute a rich source of biologically active compounds used for the treatment of many psychiatric disorders, such as anxiety disorders and depression. Generalized anxiety disorder has increased significantly, being the second most prevalent disorder in care facilities to public health. Depression is considered a chronic and common psychiatric disorder that affects 350 million people of all ages around the world. In this context, the pharmacological intervention conduits have been employed, effective, although leave to be desired when observed adverse effects. The genus Passiflora is commonly commercially known by its fruit, but is also widely used in traditional Brazilian medicine. Passiflora edulis displays considerable morphological variability. This plant produces two types of fruit: Purple (Passiflora edulis Sims fo. edulis) and yellow (Passiflora edulis fo. flavicarpa Degener). This study investigated the central effects of aqueous extract of the leaves of the two varieties of the species Passiflora edulis in tests used to assess behavior related to anxiety and depression, as well as investigating the potential effect of the antidepressant-like fractions of edulis fo. edulis and neuropharmacological mechanisms responsible for this action. To conduct this study used male Swiss mice (2 months old, weighing 30-35 g). The animals received the aqueous extract of the leaves of the two species of Passiflora: edulis fo. edulis (100, 300, 1000 mg / kg) and fractions ethyl acetate, butanol and aqueous waste (25, 50, 75, 100 mg / kg) and edulis fo. flavicarpa (30, 100, 300, 1000 mg / kg) or saline by gavage 60 minutes prior to the maze tests at high cross the open field test, test forced swim test and sedation induced by thiopental. To investigate the mechanism of action of the activity of antidepressant type of fractions the following drugs were used: PCPA (inhibitor of 5-HT synthesis) AMPT (inhibitor of catecholamine synthesis), DSP-4 (noradrenergic neurotoxin) and Sulpiride (antagonist selective dopamine D2 receptor). They were used as a standard positive control, fluoxetine and nortriptyline. The results of the phytochemical profile show very different characteristics to the aqueous extract of the varieties of Passiflora edulis "flavicarpa" and "edulis". The aqueous extracts of both varieties of Passiflora edulis share anxiolytic activity type (edulis fo. edulis 300 mg/kg; edulis fo. flavicarpa 300 and 1000 mg/kg) and antidepressant (edulis fo. edulis 300 mg/kg; edulis fo flavicarpa 1000 mg/kg), while the effect hipolocomotor/sedative was only seen for edulis fo. edulis (1000 mg/kg). Both fractions ethyl acetate, butanol aqueous extract edulis fo. edulis showed activity type antidepressant at a dose of 50 mg/kg in the forced swim test. The data suggest that the effect of antidepressant-like fractions edulis fo. edulis involves catecholaminergic and serotonergic neurotransmission, particularly dopaminergic, there is seen that pre-treatment DSP-4 is not affected antidepressant action of fractions as was dependent activation of dopamine D2 receptors.

Avaliação de duas variedades de Passiflora edulis sobre as respostas comportamentais de camundongos e um possível mecanismo de ação

The medicinal plants constitute a rich source of biologically active compounds used for the treatment of many psychiatric disorders, such as anxiety disorders and depression. Generalized anxiety disorder has increased significantly, being the second most prevalent disorder in care facilities to public health. Depression is considered a chronic and common psychiatric disorder that affects 350 million people of all ages around the world. In this context, the pharmacological intervention conduits have been employed, effective, although leave to be desired when observed adverse effects. The genus Passiflora is commonly commercially known by its fruit, but is also widely used in traditional Brazilian medicine. Passiflora edulis displays considerable morphological variability. This plant produces two types of fruit: Purple (Passiflora edulis Sims fo. edulis) and yellow (Passiflora edulis fo. flavicarpa Degener). This study investigated the central effects of aqueous extract of the leaves of the two varieties of the species Passiflora edulis in tests used to assess behavior related to anxiety and depression, as well as investigating the potential effect of the antidepressant-like fractions of edulis fo. edulis and neuropharmacological mechanisms responsible for this action. To conduct this study used male Swiss mice (2 months old, weighing 30-35 g). The animals received the aqueous extract of the leaves of the two species of Passiflora: edulis fo. edulis (100, 300, 1000 mg / kg) and fractions ethyl acetate, butanol and aqueous waste (25, 50, 75, 100 mg / kg) and edulis fo. flavicarpa (30, 100, 300, 1000 mg / kg) or saline by gavage 60 minutes prior to the maze tests at high cross the open field test, test forced swim test and sedation induced by thiopental. To investigate the mechanism of action of the activity of antidepressant type of fractions the following drugs were used: PCPA (inhibitor of 5-HT synthesis) AMPT (inhibitor of catecholamine synthesis), DSP-4 (noradrenergic neurotoxin) and Sulpiride (antagonist selective dopamine D2 receptor). They were used as a standard positive control, fluoxetine and nortriptyline. The results of the phytochemical profile show very different characteristics to the aqueous extract of the varieties of Passiflora edulis "flavicarpa" and "edulis". The aqueous extracts of both varieties of Passiflora edulis share anxiolytic activity type (edulis fo. edulis 300 mg/kg; edulis fo. flavicarpa 300 and 1000 mg/kg) and antidepressant (edulis fo. edulis 300 mg/kg; edulis fo flavicarpa 1000 mg/kg), while the effect hipolocomotor/sedative was only seen for edulis fo. edulis (1000 mg/kg). Both fractions ethyl acetate, butanol aqueous extract edulis fo. edulis showed activity type antidepressant at a dose of 50 mg/kg in the forced swim test. The data suggest that the effect of antidepressant-like fractions edulis fo. edulis involves catecholaminergic and serotonergic neurotransmission, particularly dopaminergic, there is seen that pre-treatment DSP-4 is not affected antidepressant action of fractions as was dependent activation of dopamine D2 receptors.

Efeito de agentes de controle sobre a qualidade reprodutiva de rainhas de Apis mellifera L. (Hymenoptera: Apidae) africanizadas

The agriculture with the use of products with less environmental impact is expanding. In it, the producers offer their products without the use of synthetic chemical inputs, solving the phytosanitary problems with the use of biological or alternative control agents such as parasites, predators, entomopathogenic, alternative products, plant extracts and essential oils. These products can be considered safe to non-target organisms, but studies are needed to find these features on natural enemies and on the beneficial insects such as bees, common frequenter of cultures. In this sense, this study aims to evaluate the effects of control over reproductive quality queens of Apis mellifera L. (Hymenoptera: Apidae) Africanized. For this, it tested the action of control products on the production of A. mellifera queens, using the commercial entomopathogenic fungus Boveril® 1,0x108 (Beauveria bassiana) and aqueous extract of pomegranate (Punica granatum) at a concentration of 5% sterile distilled water with Tween (0.01%) and sterile distilled water (controls). The treatments were incorporated into a tissue type gauze, wrapped in an acrylic plate and packed inside minirrecrias type colonies for the production of queens on the day before the transfer of larvae. The next day were introduced battens with 30 domes with larvae to produce queens, so the workers have contacted the agent tested. From the emergence of all the queens, they were monitored to determine the measures of body weight (mg), length and width of wing and abdomen, length, width and height of the chest (mm) as well as the time of emergence of queens. The next step was evaluated the influence of the control agents in production creates, performing measurements of creating areas in cm2 for six straight weeks. It was found that the area creates Queens did not differ among the treatments. Histological analysis of hipofaringeanas of workers glands that came into contact with the control agents and the midgut of virgin queens were also held. Histological analysis differences were observed in the tissues when the treatments were compared with the respective controls.

Inibição de linhagens do complexo Fusarium Graminearum por compostos naturais e sintéticos

Quando produtos alimentícios e especiarias são contaminados por micotoxinas é quase impossível detoxificar utilizando processos usuais da indústria de alimentos ou durante o preparo doméstico. Por isso, controlar o crescimento do fungo e a produção de toxinas é uma demanda para garantir a segurança alimentar. Os agrotóxicos são rotineiramente utilizados como estratégia para proteger as plantas de doenças provocadas pela contaminação fúngica. No entanto, eles estão associados a efeitos adversos ao sistema nervoso central e periférico, têm ação imunodepressora e são cancerígenos. Em virtude disso, o objetivo deste trabalho foi estudar a inibição do desenvolvimento, do potencial toxigênico e da expressão gênica de linhagens do Complexo Fusarium graminearum por compostos naturais comparativamente aos fungicidas azoxistrobina e trifloxistrobina. Do farelo de arroz, foram extraídos o γ-orizanol e os ácidos fenólicos (EFF). Das sementes de nim foram extraídos os ácidos fenólicos (EFN), totalizando três extratos naturais. A capacidade antioxidante dos extratos foi verificada pelo consumo do radical livre DPPH• , capacidade de captura do radical ABTS●+, redução do ferro e inibição da oxidação enzimática. Os mecanismos de inibição de três linhagens de F. graminearum foram avaliados através da determinação de compostos estruturais (glicosamina e ergosterol) e da atividade de enzimas do metabolismo primário (α- amilase e proteases). Foram determinadas as micotoxinas de Fusarium: deoxinivalenol (DON), 15 acetildeoxinivalenol (15AcDON), 3 acetildeoxinivalenol (3AcDON), nivalenol (NIV) e zearalenona (ZEA). A expressão dos genes Tri1 e Tri5 foi determinada a fim de verificar se ocorria modificação da expressão gênica nas linhagens do Complexo F. graminearum ocasionada pela presença dos antifúngicos. O EFF apresenta atividade antioxidante destacada em relação aos demais extratos naturais para inibir a iniciação do processo, a propagação do radical livre e a catálise enzimática. A presença dos compostos naturais mostrou efeito promissor como antifúngico para as linhagens, sendo que a concentração necessária para inibir 50% do crescimento radial das colônias (MIC50) foi 0,9 g/kg para γ-orizanol; 0,032 g/kg para EFF e 0,037 g/kg para EFN, portanto, os extratos fenólicos são mais eficazes para inibição de F. graminearum do que o γ-orizanol. Os extratos naturais afetaram as atividades das enzimas α-amilase e proteases. Também ocorreu a redução da formação de componentes estruturais (glicosamina e ergosterol). Os extratos naturais se destacaram pela capacidade de inibição de micotoxinas produzidas pela biomassa fúngica, com destaque para o EFN sobre a produção de DON, 15AcDON, 3AcDON e ZEA. Sendo assim, é possível dizer que há uma relação direta entre a atividade antioxidante na inibição do fungo e na manifestação do seu potencial toxigênico. Além disso, esse estudo contribuiu com a elucidação do mecanismo de ação dos antifúngicos naturais estudados. Ocorre modificação na expressão gênica quando a linhagem é submetida ao tratamento com antifúngico, havendo uma relação direta entre a expressão do gene Tri5 e a produção de DON.