Resumo
The present study was conducted to evaluate the chemical composition, antioxidant activity and hypoglycemic effects of whole kumquat (Ku) powder in diabetic rats fed a high-fat-high-cholesterol (HFHC) diet. The antioxidant activities were evaluated using stable 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical scavenging method, 2,2'-azinobis (3-ethyl benzo thiazoline-6-sulphonic acid) radical cation (ABTS) and Ferric reducing antioxidant power (FRAP). Total phenolic content was (51.85 mg GAE/g) and total flavonoid content was (0.24 mg Cateachin Equivalent, CE/g). DPPH and ABTS values were 3.32 and 3.98 mg Trolox equivalent (TE)/g where FRAP value was 3.00 mM Fe²+/kg dry material. A total of 90 albino rats were used in the present study. Rats group were as follows: normal diet; normal treated (2, 4, and 6% Ku.), diabetic rats (non-treated), diabetic + HFHC diet (non-treated), HFHC (non-treated), Diabetic (treated), HFHC (treated) and Diabetic + HFHC (treated). The diets were followed for 8 weeks. Blood samples were collected at the end of the experiment. Serum glucose was recorded and thyroid hormones (T4, Thyroxine and T3, Triiodothyronine) were conducted. Diet supplemented with Kumquat at different concentrations have a hypoglycemic effect and improve the thyroid hormones of both diabetic rats and HFHC diabetic rats.
O presente estudo foi conduzido para avaliar a composição química, a atividade antioxidante e os efeitos hipoglicêmicos do pó de kumquat (Ku) em ratos diabéticos alimentados com uma dieta rica em gordura e colesterol (HFHC). As atividades antioxidantes foram avaliadas usando o método de eliminação de radicais livres de 1,1-difenil 2-picrilhidrazil (DPPH), 2,2'-azinobis (ácido 3-etilbenzotiazolina-6-sulfônico) radical cátion (ABTS) e antioxidante redutor férrico potência (FRAP). O conteúdo fenólico total foi (51,85 mg GAE / g) e o conteúdo total de flavonoides foi (0,24 mg Cateachin Equivalent, CE / g). Os valores de DPPH e ABTS foram 3,32 e 3,98 mg equivalente de Trolox (TE) / g, em que o valor de FRAP foi de 3,00 mM Fe²+ / kg de material seco. Um total de 90 ratos albinos foi usado no presente estudo. O grupo dos ratos foi o seguinte: dieta normal: tratados normais (2, 4 e 6% Ku.), ratos diabéticos (não tratados), diabéticos + dieta HFHC (não tratados), HFHC (não tratados), diabéticos (tratados), HFHC (tratados) e diabéticos + HFHC (tratados). As dietas foram seguidas por 8 semanas. Amostras de sangue foram coletadas ao final do experimento. A glicose sérica foi registrada e os hormônios tireoidianos (T4, Tiroxina e T3, Triiodotironina) foram conduzidos. A dieta suplementada com kumquat em diferentes concentrações tem um efeito hipoglicêmico e melhora os hormônios tireoidianos tanto de ratos diabéticos quanto de ratos diabéticos com HFHC.
Assuntos
Animais , Ratos , Antioxidantes/análise , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/análise , Hormônios Tireóideos/farmacologia , Ratos/metabolismo , Ratos/sangue , Rutaceae/químicaResumo
Abstract The present study was conducted to evaluate the chemical composition, antioxidant activity and hypoglycemic effects of whole kumquat (Ku) powder in diabetic rats fed a high-fat-high-cholesterol (HFHC) diet. The antioxidant activities were evaluated using stable 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical scavenging method, 2,2´-azinobis (3-ethyl benzo thiazoline-6-sulphonic acid) radical cation (ABTS) and Ferric reducing antioxidant power (FRAP). Total phenolic content was (51.85 mg GAE/g) and total flavonoid content was (0.24 mg Cateachin Equivalent, CE/g). DPPH and ABTS values were 3.32 and 3.98 mg Trolox equivalent (TE)/g where FRAP value was 3.00 mM Fe2+/kg dry material. A total of 90 albino rats were used in the present study. Rats group were as follows: normal diet; normal treated (2, 4, and 6% Ku.), diabetic rats (non-treated), diabetic + HFHC diet (non-treated), HFHC (non-treated), Diabetic (treated), HFHC (treated) and Diabetic + HFHC (treated). The diets were followed for 8 weeks. Blood samples were collected at the end of the experiment. Serum glucose was recorded and thyroid hormones (T4, Thyroxine and T3, Triiodothyronine) were conducted. Diet supplemented with Kumquat at different concentrations have a hypoglycemic effect and improve the thyroid hormones of both diabetic rats and HFHC diabetic rats.
Resumo O presente estudo foi conduzido para avaliar a composição química, a atividade antioxidante e os efeitos hipoglicêmicos do pó de kumquat (Ku) em ratos diabéticos alimentados com uma dieta rica em gordura e colesterol (HFHC). As atividades antioxidantes foram avaliadas usando o método de eliminação de radicais livres de 1,1-difenil 2-picrilhidrazil (DPPH), 2,2-azinobis (ácido 3-etilbenzotiazolina-6-sulfônico) radical cátion (ABTS) e antioxidante redutor férrico potência (FRAP). O conteúdo fenólico total foi (51,85 mg GAE / g) e o conteúdo total de flavonoides foi (0,24 mg Cateachin Equivalent, CE / g). Os valores de DPPH e ABTS foram 3,32 e 3,98 mg equivalente de Trolox (TE) / g, em que o valor de FRAP foi de 3,00 mM Fe2 + / kg de material seco. Um total de 90 ratos albinos foi usado no presente estudo. O grupo dos ratos foi o seguinte: dieta normal: tratados normais (2, 4 e 6% Ku.), ratos diabéticos (não tratados), diabéticos + dieta HFHC (não tratados), HFHC (não tratados), diabéticos (tratados), HFHC (tratados) e diabéticos + HFHC (tratados). As dietas foram seguidas por 8 semanas. Amostras de sangue foram coletadas ao final do experimento. A glicose sérica foi registrada e os hormônios tireoidianos (T4, Tiroxina e T3, Triiodotironina) foram conduzidos. A dieta suplementada com kumquat em diferentes concentrações tem um efeito hipoglicêmico e melhora os hormônios tireoidianos tanto de ratos diabéticos quanto de ratos diabéticos com HFHC.
Resumo
Abstract The present study was conducted to evaluate the chemical composition, antioxidant activity and hypoglycemic effects of whole kumquat (Ku) powder in diabetic rats fed a high-fat-high-cholesterol (HFHC) diet. The antioxidant activities were evaluated using stable 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical scavenging method, 2,2´-azinobis (3-ethyl benzo thiazoline-6-sulphonic acid) radical cation (ABTS) and Ferric reducing antioxidant power (FRAP). Total phenolic content was (51.85 mg GAE/g) and total flavonoid content was (0.24 mg Cateachin Equivalent, CE/g). DPPH and ABTS values were 3.32 and 3.98 mg Trolox equivalent (TE)/g where FRAP value was 3.00 mM Fe2+/kg dry material. A total of 90 albino rats were used in the present study. Rats group were as follows: normal diet; normal treated (2, 4, and 6% Ku.), diabetic rats (non-treated), diabetic + HFHC diet (non-treated), HFHC (non-treated), Diabetic (treated), HFHC (treated) and Diabetic + HFHC (treated). The diets were followed for 8 weeks. Blood samples were collected at the end of the experiment. Serum glucose was recorded and thyroid hormones (T4, Thyroxine and T3, Triiodothyronine) were conducted. Diet supplemented with Kumquat at different concentrations have a hypoglycemic effect and improve the thyroid hormones of both diabetic rats and HFHC diabetic rats.
Resumo O presente estudo foi conduzido para avaliar a composição química, a atividade antioxidante e os efeitos hipoglicêmicos do pó de kumquat (Ku) em ratos diabéticos alimentados com uma dieta rica em gordura e colesterol (HFHC). As atividades antioxidantes foram avaliadas usando o método de eliminação de radicais livres de 1,1-difenil 2-picrilhidrazil (DPPH), 2,2'-azinobis (ácido 3-etilbenzotiazolina-6-sulfônico) radical cátion (ABTS) e antioxidante redutor férrico potência (FRAP). O conteúdo fenólico total foi (51,85 mg GAE / g) e o conteúdo total de flavonoides foi (0,24 mg Cateachin Equivalent, CE / g). Os valores de DPPH e ABTS foram 3,32 e 3,98 mg equivalente de Trolox (TE) / g, em que o valor de FRAP foi de 3,00 mM Fe2 + / kg de material seco. Um total de 90 ratos albinos foi usado no presente estudo. O grupo dos ratos foi o seguinte: dieta normal: tratados normais (2, 4 e 6% Ku.), ratos diabéticos (não tratados), diabéticos + dieta HFHC (não tratados), HFHC (não tratados), diabéticos (tratados), HFHC (tratados) e diabéticos + HFHC (tratados). As dietas foram seguidas por 8 semanas. Amostras de sangue foram coletadas ao final do experimento. A glicose sérica foi registrada e os hormônios tireoidianos (T4, Tiroxina e T3, Triiodotironina) foram conduzidos. A dieta suplementada com kumquat em diferentes concentrações tem um efeito hipoglicêmico e melhora os hormônios tireoidianos tanto de ratos diabéticos quanto de ratos diabéticos com HFHC.
Assuntos
Animais , Ratos , Rutaceae , Diabetes Mellitus Experimental/tratamento farmacológico , Pós , Hormônios Tireóideos , Glicemia , FrutasResumo
The present study was conducted to evaluate the chemical composition, antioxidant activity and hypoglycemic effects of whole kumquat (Ku) powder in diabetic rats fed a high-fat-high-cholesterol (HFHC) diet. The antioxidant activities were evaluated using stable 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical scavenging method, 2,2'-azinobis (3-ethyl benzo thiazoline-6-sulphonic acid) radical cation (ABTS) and Ferric reducing antioxidant power (FRAP). Total phenolic content was (51.85 mg GAE/g) and total flavonoid content was (0.24 mg Cateachin Equivalent, CE/g). DPPH and ABTS values were 3.32 and 3.98 mg Trolox equivalent (TE)/g where FRAP value was 3.00 mM Fe²+/kg dry material. A total of 90 albino rats were used in the present study. Rats group were as follows: normal diet; normal treated (2, 4, and 6% Ku.), diabetic rats (non-treated), diabetic + HFHC diet (non-treated), HFHC (non-treated), Diabetic (treated), HFHC (treated) and Diabetic + HFHC (treated). The diets were followed for 8 weeks. Blood samples were collected at the end of the experiment. Serum glucose was recorded and thyroid hormones (T4, Thyroxine and T3, Triiodothyronine) were conducted. Diet supplemented with Kumquat at different concentrations have a hypoglycemic effect and improve the thyroid hormones of both diabetic rats and HFHC diabetic rats.(AU)
O presente estudo foi conduzido para avaliar a composição química, a atividade antioxidante e os efeitos hipoglicêmicos do pó de kumquat (Ku) em ratos diabéticos alimentados com uma dieta rica em gordura e colesterol (HFHC). As atividades antioxidantes foram avaliadas usando o método de eliminação de radicais livres de 1,1-difenil 2-picrilhidrazil (DPPH), 2,2'-azinobis (ácido 3-etilbenzotiazolina-6-sulfônico) radical cátion (ABTS) e antioxidante redutor férrico potência (FRAP). O conteúdo fenólico total foi (51,85 mg GAE / g) e o conteúdo total de flavonoides foi (0,24 mg Cateachin Equivalent, CE / g). Os valores de DPPH e ABTS foram 3,32 e 3,98 mg equivalente de Trolox (TE) / g, em que o valor de FRAP foi de 3,00 mM Fe²+ / kg de material seco. Um total de 90 ratos albinos foi usado no presente estudo. O grupo dos ratos foi o seguinte: dieta normal: tratados normais (2, 4 e 6% Ku.), ratos diabéticos (não tratados), diabéticos + dieta HFHC (não tratados), HFHC (não tratados), diabéticos (tratados), HFHC (tratados) e diabéticos + HFHC (tratados). As dietas foram seguidas por 8 semanas. Amostras de sangue foram coletadas ao final do experimento. A glicose sérica foi registrada e os hormônios tireoidianos (T4, Tiroxina e T3, Triiodotironina) foram conduzidos. A dieta suplementada com kumquat em diferentes concentrações tem um efeito hipoglicêmico e melhora os hormônios tireoidianos tanto de ratos diabéticos quanto de ratos diabéticos com HFHC.(AU)
Assuntos
Animais , Ratos , Rutaceae/química , Antioxidantes/análise , Hipoglicemiantes/análise , Ratos/metabolismo , Ratos/sangue , Diabetes Mellitus/tratamento farmacológico , Hormônios Tireóideos/farmacologiaResumo
Because of their immense economic, wellness, and remedial value, the seeds of palm (Phoenix dactylifera) were selected with synthesized silver nanoparticles (AgNPs) based on their properties for increasing the antibacterial efficacy of medical cotton. This study aimed to be contingent upon the characterisation of raw cotton fabrics treated by AgNPs with date seed extract (DSE) of P. dactylifera both individually and in combination and to investigate their antibacterial activity against various human pathogens. The prepared cotton materials with the synthesized AgNPs and/or DSE were described by both X-ray diffraction (XRD) and scanning electron microscope (SEM). At the same time, gas chromatography-mass spectrometry (GC-MS) and High-performance liquid chromatography (HPLC) were employed to determine the bioactive components in the aqueous date seed extract. The greater antibacterial activity was recorded by cotton treated with DSE and AgNPs mix, in which inhibition zones of all treatments were against Escherichia coli (8 cm), followed by Staphylococcus aureus (2.33-5.87cm) and Bacillus subtilis (2.17-4.63 cm), respectively. Overall, these findings indicate that treated cotton fabrics with synthesised AgNPs and DSE may be widely applied in various potential biological and medical applications, which could enhance environmental sustainability in closed production and consumption.
Devido ao imenso valor econômico, propriedades curativas e de bem-estar, as sementes de palmeira (Phoenix dactylifera) foram selecionadas com nanopartículas de prata sintetizadas (AgNPs), com base em suas propriedades, visando aumentar a eficácia antibacteriana do algodão medicinal. Este estudo teve como objetivo a caracterização de tecidos de algodão cru tratados por AgNPs com extrato de semente de tâmara (DSE) de P. dactylifera tanto individualmente quanto em combinação e investigar sua atividade antibacteriana contra vários patógenos humanos. Os materiais de algodão preparados com os AgNPs sintetizados e/ou DSE foram descritos por difração de raios-X (XRD) e microscópio eletrônico de varredura (SEM). Ao mesmo tempo, cromatografia gasosa-espectrometria de massa (GC-MS) e cromatografia líquida de alta eficiência (HPLC) foram empregadas para determinar os componentes bioativos no extrato aquoso de sementes de tâmaras. A maior atividade antibacteriana foi registrada pelo algodão tratado com mistura de DSE e AgNPs, em que os halos de inibição de todos os tratamentos foram contra Escherichia coli (8 cm), seguido por Staphylococcus aureus (2,33-5,87 cm) e Bacillus subtilis (2,17-4,63 cm), respectivamente. De modo geral, essas descobertas indicam que os tecidos de algodão tratados com AgNPs sintetizados e DSE podem ser amplamente aplicados em várias aplicações biológicas e médicas potenciais, o que pode aumentar a sustentabilidade ambiental na produção e consumo fechados.
Assuntos
Prata , Extratos Vegetais , Gossypium , Nanopartículas , PhoeniceaeResumo
Araucaria angustifolia characterizes mixed Ombrophilous Forests. This Paraná pine tree has been of great economic, cultural and social importance for southern Brazil. Its cutting is restricted, as it is threatened with extinction and the use of its seed has been encouraged. This study highlights scientific research on this conifer by bibliometric analysis and reviews trends in new research on its seed and some of its food applications. The Web of Science© database revealed 620 scientific articles and the bibliometric analysis through VOSviewer showed the worldwide interest in growing. The increase in research in the areas of silviculture, phytoscience and ecology reflects the concern with the preservation of "Matas das Araucárias". Concurrently, research in food science and technology has increased, as pine nut seed can produce starch-rich food flour with low glycemic response and source of dietary fiber and some minerals. Also, along with its husk, provide bioactive compounds with potential application in the special food, active/smart and reinforced packaging and even pharmacological industries.
A Araucaria angustifolia caracteriza as Florestas Ombrófilas mistas. Este pinheiro do Paraná tem tido grande importância econômica, cultural e social para o Sul do Brasil. Seu corte está restrito, pois está ameaçada de extinção e o uso de sua semente tem sido incentivado. Este estudo destaca as pesquisas científicas sobre esta conífera por análise bibliométrica e revisa as tendências de novas pesquisas sobre sua semente e algumas de suas aplicações alimentícias. A base de dados Web of Science© revelou 620 artigos científicos e a análise bibliométrica por meio do VOSviewer demonstrou o interesse mundial em ascendência. O aumento das pesquisas nas áreas de silvicultura, fitociência e ecologia refletem à preocupação com a preservação das Matas das Araucárias. Concomitantemente, pesquisas em ciência e tecnologia de alimentos têm aumentado, pois a semente de pinhão pode produzir uma farinha alimentar rica em amido com baixa resposta glicêmica e fonte de fibra dietética e de alguns minerais. Ainda, junto com sua casca, disponibilizar compostos bioativos com potencial de aplicação nas indústrias de alimento especial, de embalagem ativa/inteligente e reforçada e, até mesmo, farmacológica.
Assuntos
Amido , Bibliometria , Conservação dos Recursos Naturais , Compostos Fitoquímicos , AraucariaResumo
Double pruning extended the harvest season of wine grape (Vitis vinifera L.) to dry winter, enabling production of high quality wines in the southeastern Brazil. Winter harvest allows grapes to fulfill not only technological maturation, but also phenolic ripeness. Winter wines from Syrah grapes harvested from eight vineyards in southeastern Brazil during three harvests were analyzed for their chemical and aromatic composition after bottling and after ageing for 20, 30, and 42 months in bottle. Winter wines have high content of total phenolic compounds, which remained almost constant through ageing, as well as color intensity. Malvidin 3-O-glucoside stood out among anthocyanins, remaining 5-10 % after 39 months of ageing. Moreover, malvidin 3-O-glucoside-pyruvic acid was the main pyranoanthocyanin identified in winter wine. Polymerized pigments index ranged from 54 % at bottling to 80 % after 42 months of ageing. Young winter wines are rich in ester and monoterpene, as well as alcoholic volatile compounds responsible for ethereal, fruity, flowery, fresh and sweet aromas. Aged winter wines showed higher contents of furfural, geranyl ethyl ether, isoamyl decanoate, α-muurolene and α-calacorene, contributing to sweet, fruity and woody aromas. Syrah winter wines are characterized by high content of phenolic compounds and color stability, and keep good sensorial characteristics after ageing in bottle.
Assuntos
Compostos Fenólicos , Conservação de Alimentos/métodos , Vinho/análise , Vinho/classificação , Indústria de EngarrafamentoResumo
Double pruning extended the harvest season of wine grape (Vitis vinifera L.) to dry winter, enabling production of high quality wines in the southeastern Brazil. Winter harvest allows grapes to fulfill not only technological maturation, but also phenolic ripeness. Winter wines from Syrah grapes harvested from eight vineyards in southeastern Brazil during three harvests were analyzed for their chemical and aromatic composition after bottling and after ageing for 20, 30, and 42 months in bottle. Winter wines have high content of total phenolic compounds, which remained almost constant through ageing, as well as color intensity. Malvidin 3-O-glucoside stood out among anthocyanins, remaining 5-10 % after 39 months of ageing. Moreover, malvidin 3-O-glucoside-pyruvic acid was the main pyranoanthocyanin identified in winter wine. Polymerized pigments index ranged from 54 % at bottling to 80 % after 42 months of ageing. Young winter wines are rich in ester and monoterpene, as well as alcoholic volatile compounds responsible for ethereal, fruity, flowery, fresh and sweet aromas. Aged winter wines showed higher contents of furfural, geranyl ethyl ether, isoamyl decanoate, α-muurolene and α-calacorene, contributing to sweet, fruity and woody aromas. Syrah winter wines are characterized by high content of phenolic compounds and color stability, and keep good sensorial characteristics after ageing in bottle.(AU)
Assuntos
Vinho/análise , Vinho/classificação , Conservação de Alimentos/métodos , Compostos Fenólicos , Indústria de EngarrafamentoResumo
Bees generally use different botanical sources of resins for the production of propolis. The elucidation of botanical sources of propolis and identification of the effects of seasonality on the chemical profile of propolis are recognized as two important aspects in the development of a high quality product. Thus, our objective was to elucidate the botanical source and identify the effect of the seasons on the chemical profile of propolis produced in southern Brazil. The chemical profile of the samples was analysed by spectrophotometric and chromatographic techniques and the results were coupled to multivariate analysis. Field observation of the foraging behaviour of Apis mellifera L. revealed its preference for the Baccharis dracunculifolia DC. species. p-Coumaric acid, 3, 4-dicaffeoylquinic acid, 3, 5-dicaffeoylquinic acid, drupanin, and artepillin C which were identified in both plant and propolis samples. Moreover, higher artepillin C amounts have been detected in samples collected in the summer and autumn, while the main compounds of p-coumaric acid and quercetin were available in spring and winter sampled propolis, respectively. Baccharis dracunculifolia has been identified as a plant species preferred by A. mellifera in foraging resin for the production of propolis in southern Brazil. The contents of balsam, total phenolic compounds, and flavonoids varied significantly over the seasons, with values above the minimum required by the legislation, thus assuring a quality pattern for this biomass.
Assuntos
Animais , Própole/agonistas , Própole/análise , Abelhas , Baccharis , Estações do AnoResumo
Bees generally use different botanical sources of resins for the production of propolis. The elucidation of botanical sources of propolis and identification of the effects of seasonality on the chemical profile of propolis are recognized as two important aspects in the development of a high quality product. Thus, our objective was to elucidate the botanical source and identify the effect of the seasons on the chemical profile of propolis produced in southern Brazil. The chemical profile of the samples was analysed by spectrophotometric and chromatographic techniques and the results were coupled to multivariate analysis. Field observation of the foraging behaviour of Apis mellifera L. revealed its preference for the Baccharis dracunculifolia DC. species. p-Coumaric acid, 3, 4-dicaffeoylquinic acid, 3, 5-dicaffeoylquinic acid, drupanin, and artepillin C which were identified in both plant and propolis samples. Moreover, higher artepillin C amounts have been detected in samples collected in the summer and autumn, while the main compounds of p-coumaric acid and quercetin were available in spring and winter sampled propolis, respectively. Baccharis dracunculifolia has been identified as a plant species preferred by A. mellifera in foraging resin for the production of propolis in southern Brazil. The contents of balsam, total phenolic compounds, and flavonoids varied significantly over the seasons, with values above the minimum required by the legislation, thus assuring a quality pattern for this biomass.(AU)
Assuntos
Animais , Própole/análise , Própole/agonistas , Abelhas , Baccharis , Estações do AnoResumo
This study aimed to extract isoflavones from soybean molasses with different solvents, furthermore, the selected extract, which showed overall desirable characteristics was selected to evaluate the potentials of different encapsulating agents. The encapsulating agents employed for the study included 18% Maltodextrin DE20 (T1), 18% Hi-maize (T2), and a mixture of equal proportions of 9% Maltodextrin DE20 and 9% of Hi-maize (T3). Solvents such as 80% ethanol and methanol, and grain alcohol in varying different concentrations of 50 and 80% were used for the studies. The best solvent for the extraction of phenolics and total isoflavones was 50% cereal alcohol, this extract also presented higher antioxidant activity. Evaluation of the encapsulating agents revealed that 18% Hi-maize with inlet air of 130 °C was best suited for the encapsulation of isoflavones. The ORAC method showed that microcapsules with the 18% Hi-maize encapsulating agent also had higher antioxidant activity.(AU)
Este estudo teve como objetivo extrair isoflavonas do melaço de soja com diferentes solventes, além disso, o extrato selecionado com as características desejáveis em geral foi selecionado para avaliar os potenciais de diferentes agentes encapsulantes. Os agentes encapsulantes foram: 18% de maltodextrina DE20 (T1), 18% Hi-maize (T2) e uma mistura em proporções iguais de 9 % de maltodextrina DE20 e 9% de Hi-maize (T3). Foram testados os solventes, etanol e metanol a 80% e álcool de cereais a 50 e 80%. O melhor solvente para a extração de fenólicos e isoflavonas totais foi o álcool de cereais a 50%, sendo que este extrato também apresentou maior atividade antioxidante. Entre os agentes encapsulantes testados, 18% Hi-maize com ar de entrada de 130 °C mostrou ser o melhor para encapsular as isoflavonas. O método ORAC mostrou que as microcápsulas com o agente encapsulante Hi-maize a 18% também apresentaram maior atividade antioxidante.(AU)
Assuntos
Alimentos de Soja , Isoflavonas , Compostos Fenólicos , Composição de MedicamentosResumo
Abstract The halophyte species Plantago coronopus has several described ethnomedicinal uses, but few reported biological activities. This work carried out for the first time a comparative analysis of P. coronopus organs in terms of phenolic composition and antioxidant activity of organic and water extracts from roots, leaves and flowers. The leaves contents in selected nutrients, namely amino acids and minerals, are also described. Roots (ethyl acetate and methanol extracts) had the highest radical scavenging activity (RSA) towards 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, while leaves (hexane extract) had higher RSA on nitric oxide radical and iron chelating ability. High performance liquid chromatography (HPLC) analysis identified eighteen phenolics from which salicylic acid and epicatechin are here firstly described in Plantago species. Leaves had mineral levels similar to those of most vegetables, proving to be a good source for elements like calcium, sodium, iron and magnesium, and also for several of the essential amino acids justifying it use as food. Our results, especially those regarding the phenolics composition, can explain the main traditional uses given to this plantain and, altogether, emphasize the potential of P. coronopus as a source of bioactive molecules particularly useful for the prevention of oxidative stress-related diseases.
Resumo A espécie halófita Plantago coronopus tem vários usos etnomedicinais já descritos, mas em relação à bioatividade a informação é escassa. Este trabalho efetuou, pela primeira vez, uma análise comparativa dos órgãos de P. coronopus em termos de compostos fenólicos e atividade antioxidante de extratos orgânicos e aquosos provenientes das raízes, folhas e flores da planta, bem como o conteúdo de determinados nutrientes, aminoácidos e minerais, nas folhas da planta. As raízes (extratos de acetato de etila e metanol) apresentaram a maior atividade de captação para os radicais 1,1-difenil-2-picril hidrazil (DPPH) e 2,2-azino-bis(3-etilbenzotiazolina-6-ácido sulfónico) (ABTS), enquanto as folhas (extrato de hexano) mostraram maior atividade captadora para o radical óxido nítrico bem como maior capacidade quelante do ferro. A análise por cromatografia liquida de alta eficiência (CLAE) identificou dezoito compostos fenólicos e, destes, o ácido salicílico e a epicatequina são aqui descritos pela primeira vez em espécies de Plantago. As folhas desta planta halófita mostraram ainda conter minerais em níveis semelhantes aos da maioria dos vegetais, provando ser uma boa fonte de elementos como o cálcio, sódio, ferro e magnésio, bem como de vários dos aminoácidos essenciais o que justifica seu uso na alimentação. Os resultados, particularmente aqueles relacionados à composição fenólica, podem justificar os principais usos medicinais atribuídos a esta espécie e, na sua totalidade, demonstram o potencial de P. coronopus como fonte de moléculas bioativas particularmente úteis na prevenção de doenças relacionadas com estresse oxidativo.
Resumo
The objective of this study was to determine the proximal composition, the physical and chemical characteristics and the in vitro antioxidant capacity (DPPH, ABTS and FRAP) of the pulp of the wild passion fruit (Passiflora glandulosa Cav.) from Cariri region, Ceara, Brazil. The results showed that the proximal composition and the caloric value of this passion fruit are similar to other species, but with a high ascorbic acid content. The fruit pulp showed low level of antioxidant activity and low level of polyphenolic compounds followed by three methodologies used. Due to high levels of titratable acidity (3.52) and total soluble solids (17.80 Brix), this fruit can be considered as a high value fruit for commerce. However, it is a species of passion fruit with few studies described in the literature, and more research is needed to assess its nutritional and functional potential.(AU)
O objetivo do estudo foi determinar a composição centesimal, as características físicas equímicas e a capacidade antioxidante (DPPH, ABTS e FRAP) in vitro da polpa do maracujá-do-mato(Passiflora glandulosa Cav.) da região do Cariri, Ceará, Brasil. Os resultados demonstraram que a composiçãocentesimal e o valor calórico desse tipo de maracujá são similares a outras espécies, mas com nível elevadode ácido ascórbico. A polpa apresentou baixo teor de polifenóis e baixa atividade antioxidante para as trêsmetodologias aplicadas. Em razão dos altos níveis de acidez titulável (3,52) e sólidos solúveis totais (17,80°Brix), este fruto pode ser considerado como um fruto de alto valor para o comércio. Porém, esta é umaespécie de maracujá pouco descrita na literatura, sendo necessárias mais análises para avaliar seu potencialvalor nutricional e funcional.(AU)
Assuntos
Passiflora/química , Antioxidantes/efeitos adversos , Antioxidantes/química , Fenômenos Químicos/análiseResumo
The objective of this study was to determine and correlate the extraction yields, antioxidant activity, total phenolics and total flavonoids from grape, mango and peanut agro-industrial by-products. The β-carotene/linoleic acid autoxidation system and scavenging capacity for DPPH and ABTS free radicals assays were used. The results were expressed in terms of lyophilized sample or dry extract. Mango bagasse exhibited the highest extraction yield (37.07%) followed by peanut skin (15.17%) and grape marc (7.92%). In terms of lyophilized sample, total phenolics did not vary significantly among the residues evaluated (average of 60.33mg EAG g-1); however, when they were expressed as dry extract grape marc exhibited the highest total phenolic (768.56±116.35mg GAE g-1), followed by peanut skin (404.40±13.22mg GAE g-1) and mango bagasse (160.25±4.52mg GAE g-1), Peanut skin exhibited the highest content of total flavonoids (2.44mg QE g-1), while grape marc (1.76mg QE g-1) and mango bagasse (1.70 mg QE g-1) showed no significant differences. The extraction yield showed strong negative linear correlation with total phenolic and total flavonoid. This study showed that peanut skin was the sample with the highest antioxidant activity and it was strongly influenced by total flavonoids. All extracts of byproducts showed antioxidant activity comparable to α-tocopherol, and they can be a source of natural compounds with potential to replace synthetic antioxidants such as BHT.(AU)
O objetivo deste estudo foi determinar e correlacionar os rendimentos de extração, atividade antioxidante, compostos fenólicos totais e flavonoides de subprodutos agroindustriais de uva, manga e amendoim. A autoxidação do sistema β-caroteno/ácido linoleico e a capacidade de sequestro dos radicais DPPH e ABTS foram os ensaios antioxidantes utilizados. Os resultados foram expressos com base na amostra liofilizada ou no extrato seco. O bagaço de manga apresentou o maior rendimento de extração (37,07%) seguido da película de amendoim (15,17%) e bagaço de uva (7,92%). Em termos de amostra liofilizada, o teor de fenólicos totais não variou significativamente entre os resíduos avaliados (média de 60,33mg EAG g-1), entretanto, quando foi expresso com base no extrato seco, o bagaço de uva exibiu o maior teor de fenólicos totais (768,56±116,35mg EAG g-1), seguido da película de amendoim (404,40±13,22mg EAG g-1) e bagaço de manga (160,25±4,52 mg EAG g-1). A película de amendoim apresentou o maior conteúdo de flavonoides totais (2,44mg EQ g-1), enquanto os bagaços de uva (1,76mg EQ g-1) e de manga (1,70mg EQ g-1) não mostraram diferenças significativas. O rendimento de extração mostrou fortes correlações lineares negativas como teor de fenólicos totais e flavonoides totais. Este estudo mostrou que a película de amendoim foi o material que apresentou a maior atividade antioxidante e isso foi fortemente influenciado por flavonoides totais. Os extratos avaliados mostraram atividade antioxidante comparável à do α-tocoferol, com potencial para substituir antioxidantes sintéticos, tais como o BHT.(AU)
Assuntos
Tecnologia de Alimentos/métodos , Vitis/química , Arachis/química , Mangifera/química , Antioxidantes/análise , Compostos Fenólicos/análise , Flavonoides/análise , Biomassa , Gerenciamento de ResíduosResumo
Blast, caused by Pyricularia oryzae, has become a significant disease threat to wheat (Triticum aestivum L.) in Brazil. This study aimed to investigate at the histochemical level if silicon (Si) could enhance the production of flavonoids in the leaves of wheat plants in response to P. oryzae infection. Plants from the Aliança cultivar, which are susceptible to blast, were grown in hydroponic cultures containing 0 (-Si) or 2 mM of Si (+Si) and inoculated by spraying a conidial suspension of P. oryzae (1 × 105 conidia mL1) on all adaxial leaf surfaces of plants at 60 days after emergence (growth stage 65). The fourth and fifth leaves of each plant were used to evaluate blast severity at 24, 36, 48, 72 and 96 h after inoculation (hai). At 96 hai, leaves were collected from plants to determine the foliar Si concentration. For cytological observations, leaf samples were randomly collected from the fourth and fifth leaves of each plant at 72 hai. The foliar Si concentration was higher in +Si plants (36 g kg1) in comparison to -Si plants (2.6 g kg1). This increased Si concentration was correlated with reduced fungal growth inside the epidermal cells and the development of blast symptoms on leaves. Strong fluorescence, which is an indication of the presence of flavonoids, was detected in the leaf cells of +Si plants using Neus and Wilson's reagents. A novel item of evidence is that, at the histochemical level, Si is involved in the potentiation of the biosynthetic pathway of flavonoids that increases wheat resistance to blast.
Assuntos
Doenças das Plantas , Resistência à Doença/efeitos dos fármacos , Silício/uso terapêutico , Triticum/parasitologiaResumo
Blast, caused by Pyricularia oryzae, has become a significant disease threat to wheat (Triticum aestivum L.) in Brazil. This study aimed to investigate at the histochemical level if silicon (Si) could enhance the production of flavonoids in the leaves of wheat plants in response to P. oryzae infection. Plants from the Aliança cultivar, which are susceptible to blast, were grown in hydroponic cultures containing 0 (-Si) or 2 mM of Si (+Si) and inoculated by spraying a conidial suspension of P. oryzae (1 × 105 conidia mL1) on all adaxial leaf surfaces of plants at 60 days after emergence (growth stage 65). The fourth and fifth leaves of each plant were used to evaluate blast severity at 24, 36, 48, 72 and 96 h after inoculation (hai). At 96 hai, leaves were collected from plants to determine the foliar Si concentration. For cytological observations, leaf samples were randomly collected from the fourth and fifth leaves of each plant at 72 hai. The foliar Si concentration was higher in +Si plants (36 g kg1) in comparison to -Si plants (2.6 g kg1). This increased Si concentration was correlated with reduced fungal growth inside the epidermal cells and the development of blast symptoms on leaves. Strong fluorescence, which is an indication of the presence of flavonoids, was detected in the leaf cells of +Si plants using Neus and Wilson's reagents. A novel item of evidence is that, at the histochemical level, Si is involved in the potentiation of the biosynthetic pathway of flavonoids that increases wheat resistance to blast.(AU)
Assuntos
Doenças das Plantas , Triticum/parasitologia , Silício/uso terapêutico , Resistência à Doença/efeitos dos fármacosResumo
Neste estudo, foram avaliadas as características físico-químicas e a atividade antioxidante total (AAT) da casca e da polpa das pitaias vermelha e branca. Foram determinadas a composição centesimal, vitamina C, fenólicos totais e AAT nas cascas e polpas das pitaias. A AAT foi determinada utilizando-se duas metodologias: sistema β-caroteno/ácido linoléico e sequestro do radial DPPH. As cascas e as polpas das pitaias analisadas apresentaram alto teor de umidade e baixo teor de proteínas e lipídios. Os teores de fibra alimentar total (FAT) e cinzas foram significativamente maiores nas cascas das pitaias, e os teores de glicídios e energia foram maiores nas polpas. O teor médio de vitamina C variou de 17,73 a 20,69 (mg.100 g-1) nas polpas e de 22,21 a 24,05 (mg.100 g-1) nas cascas. A casca da pitaia vermelha demonstrou menor teor de fenólicos totais (77,22 mg EAG.100 g-1). As pitaias analisadas mostraram alta AAT pela metodologia de sistema betacaroteno/ácido linoleico e baixa AAT pela técnica de DPPH. A pitaia vermelha apresentou a maior AAT com destaque na sua polpa. O potencial antioxidante e as características químicas das pitaias vermelha e branca podem contribuir na dieta benéfica à saúde humana.(AU)
This study aimed at evaluating the physicochemical characteristics and the total antioxidant activity (TAA) of the red and white pytaias peel and pulp. Centesimal composition, vitamin C, total phenolics and TAA were determined in pitayas pulp and peel samples. TAA was determined by using two methodologies: β-carotene/linoleic acid system and free DPPH radical for scavenging activity. Both the pitayas peels and pulps showed high moisture content and low protein and lipid contents. The total food fiber and ashes contents were significantly higher in pitayas peels, and the highest glucide contents and of energy were found in the pulps. The average contents of vitamin C ranged from 17.73 to 20.69 (mg.100 g-1) in pulps and from 22.21 to 24.05 (mg.100 g-1) in peel samples. The red pitaya peel showed the lowest total phenolics contents (77.22 mg EAG.100g-1). The pitayas samples demonstrated a high TAA in beta-carotene/linoleic acid system methodology and low TAA by DPPH. The red pitaya showed the highest TAA values, especially in pulp samples. The antioxidant and the chemical characteristics of the red and white pitayas may contribute to a beneficial diet for human health.(AU)
Assuntos
Humanos , Animais , Frutas , Fenótipo , Ácido Ascórbico/análise , Antioxidantes/análiseResumo
O objetivo do presente trabalho foi o de avaliar a produção de compostos fenólicos totais e atividade antioxidante da Sarcocornia ambigua em sistema de aquaponia cultivada com o Litopenaeus vannamei e expostas a diferentes intervalos de estresse hídrico (seca). Foram avaliados quatro tratamentos com três réplicas denominados de: 6 horas, 12 horas, 18 horas e 24 horas de irrigação diária, durante um período experimental de 10 semanas. Cada unidade experimental era composta por um tanque de 800 L, decantador cilindro-cônico de 40 L e uma bancada hidropônica modelada a partir do sistema de Filme Nutriente (NFT-Nutrient Film Technique), com 0,4 m2 de área total. Cada unidade experimental recebeu animais de 2,4 g com uma densidade de 250 camarões m-3 em sistema de bioflocos (BFT). Os camarões atingiram um peso médio final de 11,1±0,1 g. A produtividade de S. ambigua foi maior nos tratamentos 6 e 18 horas com 1,9±0,1 kg m-2 e 1,7±0,4 kg m-2 respectivamente, seguidos dos tratamentos 12 e 24 horas com 1,2±0,4 e 1,1±0,4 kg m-2 respectivamente. Foram encontradas diferenças significativas (p<0,05) para os compostos fenólicos totais entre os tratamentos, os maiores valores obtidos foram nos tratamentos 12 e 24 horas com concentrações de 48,43±1,8 e 47,79±1,6 mg EAG (ácido gálico equivalente) 100 g-1 MF (matéria fresca), nos tratamentos 6 e 18 horas se obteve concentrações de 42,67±1,1 e 42,63±1,3 mg EAG 100 g-1 MF. A atividade antioxidante diferiu (p<0,05) entre os tratamentos, as maiores concentrações foram encontradas nos tratamentos 12 e 24 horas com 41,3±0,6 e 43,7±0,8µmol TEAC (capacidade antioxidante equivalente ao trolox) 100 g-1 MF respectivamente enquanto nos tratamentos 6 e 18 horas as concentrações foram 29,9±0,8 e 31,1±1,5 µmol TEAC 100 g-1 MF. Houve uma recuperação média total de nitrogênio do sistema de 29,3% para os tratamentos. O presente estudo demonstrou que o tempo diário de irrigação de 12 horas no sistema aquapônico apresentou maior produção de compostos bioativos, não afetando a produtividade das plantas e dos camarões cultivados
The objective of this study was to evaluate the production of phenolic compounds and antioxidant activity of Sarcocornia ambigua in aquaponics system cultivated with Litopenaeus vannamei and exposed to different periods of water stress (drought). Four treatments were evaluated with three replicates named: 6 hours, 12 hours, 18 hours and 24 hour daily irrigation for a 10 week trial period. Each experimental unit was composed of a 800 L tank, settler-cylinder tapered 40 L and a hydroponic bench modeled from the Nutrient Film System (NFT-Nutrient Film Technique), with 0.4 m2 of total area. Each experimental unit animals received 2.4 g with a density of 250 m-3 prawns in bioflocos system (BFT). Shrimps reached an average final weight of 11.1±0.1 g. The productivity was higher in S. ambigua treatments 6 and 18 hours with 1,9±0,1 kg m-2 and 1.7±0.4 kg m-2, respectively, followed treatments of 12 and 24 hours with 1.2±0.4 and 1.1±0.4 kg m-2 respectively. There were significant differences (p<0.05) for total phenolic compounds between treatments, the highest values were obtained in treatments 12 and 24 hours with concentrations of 48.43± 1.8 and 47.79±1.6 mg EAG (gallic acid equivalent) 100 g-1 MF (fresh weight), treatments 6 and 18 hours if obtained concentrations of 42.67± 1.1 and 42.63±1.3 mg GAE 100 g-1 MF. The antioxidant activity differ (p<0.05) between treatments, the highest concentrations were found in treatments 12 and 24 hours with 41.3±0.6 and 43.7±0,8 mol TEAC (equivalent antioxidant capacity to trolox) 100 g-1 MF respectively, for treatments 6 and 18 hours, the concentrations were 29.9±0.8 and 31.1± 1.5 mol TEAC 100 g-1 MF. There was an overall average recovery of 29.3% nitrogen the system for treatment. This study showed that daily time of 12 hours in irrigation system aquapônico showed higher production of bioactive compounds, not affecting the productivity of plants and farmed shrimp
Resumo
As proantocianidinas da canela são compostos fenólicos responsáveis por diversos efeitos benéficos à saúde atribuídos a essa planta. No entanto, para usufruir desses efeitos, seria necessário consumir grande quantidade da especiaria, que apresenta algumas características sensoriais indesejáveis, como sabor forte e também causam sensação de adstringência. Pensando em resolver esses problemas, o presente trabalho teve como objetivo a obtenção do extrato de canela rico em proantocianidinas, sua encapsulação pela técnica de coacervação complexa e aplicação em sorvete. Inicialmente foram otimizadas as condições de processo para a obtenção do extrato com o maior teor de proantocianidinas. Utilizando-se canela em casca triturada, etanol 50% e variando-se condições de temperatura, razão sólido:solvente e tempo, as condições foram otimizadas em: temperatura (60 °C), razão sólido:solvente (1:7,5) e tempo de extração (30 min). Os principais compostos presentes nesse extrato foram isolados em sistema de CLAE e identificados como sendo uma mistura de proantocianidinas com graus de polimerização de 2-4, ácido cinâmico e cinamaldeído. A capacidade antioxidante dessas frações também foi determinada mostrando que as proantocianidinas são as que mais contribuem para esse potencial. O extrato foi seco por atomização e liofilização sendo avaliadas as seguintes propriedades: capacidade antioxidante, atividade inibidora da -amilase e -glicosidase e atividade antimicrobiana. Os extratos secos, principalmente o atomizado, apresentaram alta capacidade antioxidante e alto potencial de inibir as enzimas digestivas, porém perderam a capacidade antimicrobiana em relação ao extrato líquido. O extrato atomizado foi encapsulado pela técnica de coacervação complexa utilizando gelatina como polímero anfótero e diferentes polissacarídeos (goma arábica, pectina, goma de cajueiro, carboximetilcelulose e -carragena) como polímeros aniônicos. As micropartículas foram caracterizadas em relação a: teor de umidade, atividade de água, higroscopicidade,solubilidade, morfologia, tamanho e distribuição. Houve diferença entre as amostras em todos esses parâmetros avaliados. Foram estudados os espectros de infravermelho dos ingredientes e das partículas obtidas por coacervação, onde foi observada claramente a interação entre a proteína e o polissacarídeo na formação das partículas. As micropartículas foram submetidas a condições de stress em meios aquosos e se mostraram resistentes em diversos valores de pH, temperatura, concentração de sal e sacarose. Durante a estocagem as partículas perderam parte dos fenólicos e proantocianidinas totais e a amostra produzida com gelatina/-carragena, foi a que mais preservou esses compostos. Essa amostra também mostrou potencial para ser utilizada como sistema para liberação controlada de compostos fenólicos no intestino. A análise sensorial das amostras de extrato livre e encapsulado comprovou que o processo de encapsulação foi eficiente em mascarar o sabor forte e a sensação de adstringência do extrato de canela. As amostras do extrato de canela encapsulado, aplicadas em sorvete, obtiveram maior aceitação global, foram melhor avaliadas quanto ao sabor e também apresentaram maior intenção de compra pelos provadores em comparação à amostra de sorvete contendo o extrato livre.
Proanthocyanidins from cinnamon are phenolic compounds responsible for many beneficial health effects attributed to this plant. However, to take advantage of these effects, it would be necessary to consume large amount of the spice, which presents some undesirable sensory characteristics such as strong flavor and also cause sensation of astringency. Thinking of solving these problems, this study aimed to obtain a cinnamon extract rich in proanthocyanidins, its encapsulation by complex coacervation technique and application in ice cream. Initially, the conditions were optimized to obtain the extract with higher proanthocyanidins content. Using crushed cinnamon bark, 50% ethanol and varying temperature, solid to solvent ratio and time, the conditions were optimized in: temperature (60 °C) solid:solvente ratio (1:7.5), and time extraction (30 min). The main compound present in this extract were isolated on an HPLC system and identified as a mixture of proanthocyanidins with degrees of polymerisation of 2-4, cinnamaldehyde and cinnamic acid. The antioxidant capacity of these fractions was also determined showing that the proanthocyanidins are the main responsible for this potential. The extract was spray-dried and freeze-dried being evaluated the following properties: antioxidant capacity, inhibition of -amylase and -glucosidase and antimicrobial activity. Dried extracts, particularly the atomized one, showed high antioxidant capacity and high potential to inhibit digestive enzymes, but lost antimicrobial capacity in relation to the liquid extract. The atomized extract was encapsulated by the complex coacervation technique using gelatin as a amphoteric polymer and different polysaccharides (gum arabic, pectin, cashew gum, carboxymethylcellulose and -carrageenan) as the anionic polymers. The microparticles were characterized in relation to: moisture content, water activity, hygroscopicity, solubility, morphology, size and distribution. There were differences between the samples in all of these parameters evaluated. Were studied the infrared spectra of ingredients and particles obtained by coacervation, where it was clearly observed interaction between the protein and the polysaccharide in particle formation. The microparticles were submitted to stress conditions in aqueous media and were resistant to various pH values, temperature, salt concentration and sucrose. During storage, the particles have lost part of phenolics and total proanthocyanidins, and in the sample produced with gelatin/-carrageenan, these compounds were more preserved. This sample also showed potential to be used as a system for controlled release of phenolic compounds in the intestine. Sensory analysis of free and encapsulated extract samples proved that the encapsulation process was effective at masking the strong taste and the sensation of astringency of the cinnamon extract. Samples of the encapsulated cinnamon extract, added in ice cream, obtained a greater global acceptance, were further evaluated for flavor and also had a higher purchase intent by the consumers compared to the ice cream containing free extract.
Resumo
Coffee contains several bioactive compounds, highlighting the antioxidants, whose consumption has been correlated with reduced incidence of chronic and degenerative diseases. Among 100 known species of the genus Coffea the most important economically in the international trade are Coffea arabica (arabica coffee) and Coffea canephora (robusta coffee), usually found as blends in commercial products. Arabica coffees present a higher sensory quality. The components associated with the antioxidant activity (AA) of coffee beverages included the class of phenolic compounds (especially 5-CQA) and caffeine, which have been most commonly studied, and melanoidins produced in the roasting process, for whom no data are available in the literature. Different methods are used to characterize the antioxidant capacity of foods, but there is no efficient and universal methodology of measurement. In this paper, roast and ground Brazilian coffees, commercialized under different designations (37 samples) were analyzed for the level of melanoidins, by spectrophotometry, and the antioxidant activity, by ABTS and total phenolics (Folin- Ciocalteau). All the products evaluated showed significant antioxidant activity. Differences observed in the estimation of the content of melanoidins indicated different roasting processes. Considering the different categories, the Gourmet coffees were characterized fo
O café contém vários componentes bioativos, em destaque os antioxidantes, cujo consumo tem sido correlacionado a redução da incidência de doenças crônicas e degenerativas. Dentre aproximadamente 100 espécies conhecidas do gênero Coffea as mais importantes economicamente no mercado internacional são Coffea arabica (café arábica) e Coffea canephora (café conilon), usualmente encontradas como blends em produtos comerciais. O café arábica apresenta melhor qualidade sensorial. Os compostos aos quais é atribuída a atividade antioxidante (AA) das bebidas de café incluem a classe de fenóis (destaque para o 5-ACQ) e cafeína, que têm sido mais usualmente estudados, e melanoidinas, produzidas no processo de torra, para as quais dados na literatura são escassos. Diferentes métodos são utilizados para caracterizar a capacidade antioxidante de alimentos, mas não existe uma metodologia eficiente e universal de medida. Nesse trabalho, cafés torrados e moídos nacionais comercializados com diferentes denominações (37 amostras), foram analisados quanto a concentração de melanoidinas, por espectrofotometria, e atividade antioxidante pelo método ABTS e de fenólicos totais (Folin- Ciocalteau). Todos os produtos avaliados apresentaram expressiva atividade antioxidante, mas observaram-se diferenças na estimativa do teor de melanoidinas, indicando processos de torra diferenciados. Considerando-se as di