Immunomodulatory Activity of Probiotics in Models of Bacterial Infections.

As resistance to conventional antibiotics among bacteria continues to increase, researchers are increasingly focusing on alternative strategies for preventing and treating bacterial infections, one of which is microbiota modulation. The objective of this review is to analyze the scientific literature on the immunomodulatory effects of probiotics in bacterial infections. This is an integrative review of the literature based on systematic steps, with searches performed in the databases Medline, PubMed, Scopus, Embase, and ScienceDirect. The most prevalent bacterial genera used to evaluate infectious processes were Salmonella, Escherichia, Klebsiella, and Streptococcus. Lactobacillus was the most commonly used probiotic genus, with Lactobacillus delbrueckii subsp. bulgaricus is the most frequently used species. In most studies, prophylactic treatment with concentrations of probiotics equal to or greater than 8 log CFU/mL was chosen. However, there was considerable heterogeneity in terms of effective treatment duration, indicating that the results cannot be generalized across all studies. This review found that probiotics interact with the immune system through different mechanisms and have a positive effect on preventing different types of bacterial infections.

Effect of partial substitution of tomato for avocado on physico-chemical and sensory aspects of sweet-and-sour sauce.

This study aimed to develop sweet-and-sour sauces with partial substitution of tomato for avocado. Four sauces formulations containing 0%, 25%, 50%, and 75% avocado pulp were prepared. The pH, titratable acidity (TA), sugar: acid ratio, color, consistency, and syneresis analyses were performed. Sensory acceptance was measured by the hedonic, Just-about-right (JAR), and purchase intent scales. Besides, a check-all-that-apply (CATA) form was applied to obtain description data on the formulations. The results of the color parameters showed that treatments containing avocado had higher (p < 0.05) lightness and yellowness. The avocado addition improved the rheological measurements. There was an increase in the consistency of the sauces when the avocado concentration increased. The opposite was observed for syneresis, which decreased (p < 0.05) as the avocado pulp concentration increased. Sensory evaluation revealed good consumer acceptance, and purchase intent analysis showed that most consumers would buy this product. For JAR data, sauces with 50 and 75% avocado had highest values of consistency in the JAR region. The consumers who reported the formulation with 25% avocado to be "not enough" penalized its acceptance, reducing the overall acceptance. Based on the frequency of terms cited by consumers in the CATA, it was possible to consider specific terms for each formulation. The terms pleasant color, good taste, brightness, and good consistency were associated with high overall acceptance. These terms were mostly used for sauces with 25% and 50% avocado. Therefore, sweet-and-sour sauces based on a combination of tomato and avocado has proven to be a viable alternative to traditional ketchup.

Risk factors and spatial distribution associated with deaths due to COVID-19: an integrative review / Fatores de risco e distribuição espacial associados aos óbitos por COVID-19: uma revisão integrative / Factores de riesgo y distribución espacial asociados a las muertes por COVID-19: una revisión integradora

Background and objectives: understanding the clinical-epidemiological and environmental factors related to deaths due to COVID-19 and their distribution in space can serve as subsidies to direct and implement more effective health actions for vulnerable populations. Thus, the objective was to synthesize the scientific evidence related to risk factors and spatial distribution of deaths due to COVID-19 in the world. Content: this is an integrative literature review, and the following guiding question emerged: what is the scientific evidence related to risk factors and spatial distribution of deaths due to COVID-19 in the world? Searches were carried out in the Scientific Electronic Library Online (SciELO) and the Scopus, Web of Science and National Library of Medicine (PubMed) databases in June 2021. Original studies in Portuguese, English or Spanish, without time frame, excluding studies with a specific age group or with an audience with specific comorbidity, were used. A total of 25 studies were included, with findings in different scenarios around the world. Factors such as age, sex, pre-existing diseases were associated with deaths due to COVID-19, which had a heterogeneous spatial distribution and occurred in environmental, socioeconomic and geographic conditions peculiar to these territories. Conclusion: age equal to or greater than 60 years, males, cardiovascular diseases, diabetes mellitus and geographic areas with greater environmental pollution, greater population density and precarious sanitary conditions influenced the mortality of COVID-19.(AU)

Justificativa e objetivos: compreender os fatores clínico-epidemiológicos e ambientais relacionados aos óbitos por COVID-19 e sua distribuição no espaço pode servir de subsídio para direcionar e implementar ações de saúde mais efetivas para populações vulneráveis. Assim, o objetivo foi sintetizar as evidências científicas relacionadas aos fatores de risco e distribuição espacial dos óbitos por COVID-19 no mundo. Conteúdo: trata-se de uma revisão integrativa da literatura, e emergiu a seguinte questão norteadora: quais são as evidências científicas relacionadas aos fatores de risco e distribuição espacial dos óbitos por COVID-19 no mundo? As buscas foram realizadas nas bases de dados Scientific Electronic Library Online (SciELO) e Scopus, Web of Science e National Library of Medicine (PubMed) em junho de 2021. Estudos originais em português, inglês ou espanhol, sem recorte temporal, excluindo estudos com faixa etária específica ou com um público com comorbidade específica. Um total de 25 estudos foram incluídos, com achados em diferentes cenários ao redor do mundo. Fatores como idade, sexo, doenças pré-existentes foram associados aos óbitos por COVID-19, que tiveram distribuição espacial heterogênea e ocorreram em condições ambientais, socioeconômicas e geográficas peculiares a esses territórios. Conclusão: idade igual ou superior a 60 anos, sexo masculino, doenças cardiovasculares, diabetes mellitus e áreas geográficas com maior poluição ambiental, maior densidade populacional e condições sanitárias precárias influenciaram na mortalidade por COVID-19.(AU)

Justificación y objetivos: comprender los factores clínico-epidemiológicos y ambientales relacionados con las muertes por COVID-19 y su distribución en el espacio puede servir como subsidio para orientar e implementar acciones de salud más efectivas para poblaciones vulnerables. Así, el objetivo fue sintetizar la evidencia científica relacionada con los factores de riesgo y la distribución espacial de las muertes por COVID-19 en el mundo. Contenido: se trata de una revisión integrativa de la literatura, y surgió la siguiente pregunta orientadora: ¿cuál es la evidencia científica relacionada con los factores de riesgo y la distribución espacial de las muertes por COVID-19 en el mundo? Las búsquedas se realizaron en las bases de datos Scientific Electronic Library Online (SciELO) y Scopus, Web of Science y National Library of Medicine (PubMed) en junio de 2021. Estudios originales en portugués, inglés o español, sin marco de tiempo, excluyendo estudios con se utilizó un grupo de edad específico o con un público con comorbilidad específica. Se incluyeron un total de 25 estudios, con hallazgos en diferentes escenarios alrededor del mundo. Factores como la edad, el sexo, las enfermedades preexistentes se asociaron a las muertes por COVID-19, que tuvo una distribución espacial heterogénea y se produjo en condiciones ambientales, socioeconómicas y geográficas propias de estos territorios. Conclusión: la edad igual o mayor a 60 años, la maldad, las enfermedades cardiovasculares, la diabetes mellitus y las áreas geográficas con mayor contaminación ambiental, mayor densidad poblacional y precarias condiciones sanitarias influyeron en la mortalidad por COVID-19.(AU)

Deaths due to COVID-19 in a state of northeastern Brazil: spatiotemporal distribution, sociodemographic and clinical and operational characteristics.

BACKGROUND: The detection of spatiotemporal clusters of deaths by coronavirus disease 2019 (COVID-19) is essential for health systems and services, as it contributes to the allocation of resources and helps in effective decision making aimed at disease control and surveillance. Thus we aim to analyse the spatiotemporal distribution and describe sociodemographic and clinical and operational characteristics of COVID-19-related deaths in a Brazilian state. METHODS: A descriptive and ecological study was carried out in the state of Maranhão. The study population consisted of deaths by COVID-19 in the period from 29 March to 31 July 2020. The detection of spatiotemporal clusters was performed by spatiotemporal scan analysis. RESULTS: A total of 3001 deaths were analysed with an average age of 69 y, predominantly in males, of brown ethnicity, with arterial hypertension and diabetes, diagnosed mainly by reverse transcription polymerase chain reaction in public laboratories. The crude mortality rates the municipalities ranged from 0.00 to 102.24 deaths per 100 000 inhabitants and three spatiotemporal clusters of high relative risk were detected, with a mortality rate ranging from 20.25 to 91.49 deaths per 100 000 inhabitants per month. The headquarters was the metropolitan region of São Luís and municipalities with better socio-economic and health development. CONCLUSIONS: The heterogeneous spatiotemporal distribution and the sociodemographic and clinical and operational characteristics of deaths by COVID-19 point to the need for interventions.

Effect of extract or infusion of leaves of the Hibiscus sabdariffa L. in the production and storage of the beverage blends with cupuassu: physico-chemical and sensory acceptance.

This study aimed to produce beverages using extract or infusion of Hibiscus sabdariffa leaves with cupuassu pulp. The blended drinks with cold or hot extraction were formulated using the response surface methodology. Moreover, the physico-chemical and sensory stability of these beverages was performed for 180 days. The conditions production for beverage leaf extract were: 28% leaf extract, 72% cupuassu pulp, and 14°Brix. For beverage leaf infusion, were 37% leaf extract, 63% cupuassu pulp, and 13°Brix. Comparing the two beverages, the polyphenolic compounds and the antioxidant activity (ABTS and DPPH) were higher in the blends produced with leaf extract. Thus, the cold extract provided better extraction of these components in the leaves. During storage, pH, reducing and total sugars and soluble solids of blends increased linearly (p < 0.05). Nevertheless, vitamin C, polyphenolic compounds, and the antioxidant activity reduced linearly (p < 0.05). The sensory acceptance of blends containing leaf extract, in the hedonic scale, all sensory attributes were positively scored up to 135 days. At 180 days, the acceptance reduced for rejection. The blended beverage containing leaf infusion had all sensory attributes positively scored up to 90 days, with a rating between 6.27 and 7.42. At 135 and 180 days, the values were in the indifference region of the hedonic scale or acceptance region. Therefore, the blend with leaf infusion maintained better acceptance during storage when compared to leaf extract beverage. Thus, the blended beverages had good nutritional value and sensory acceptance and were acceptable for up to 135 days.

Synbiotic açaí juice (Euterpe oleracea) containing sucralose as noncaloric sweetener: Processing optimization, bioactive compounds, and acceptance during storage.

This study aimed to evaluate the fermentation process of Lacticaseibacillus casei in the açaí juice, and to evaluate the addition of fructooligosaccharides and sucrose. The organic acids, anthocyanins, polyphenolic compounds, and antioxidant activity were also investigated during fermentation. Moreover, the impact of sucrose and sucralose on microbial viability and sensory acceptance of synbiotic products was evaluated during 42 days storage at refrigerated conditions. The conditions for synbiotic juice production were the initial pH of 6.1 and fermentation undertaken at 28 °C for 22 hr. During fermentation, the higher viability was obtained when a combination of 40 g/L of FOS+10 g/L of sucrose was used (9.70 ± 0.01 log CFU/mL). The lactic acid increased from 0.82 to 1.29 g/L during the fermentation while citric acid decreased from 1.05 to 0.75 g/L. The cyanidin-3-O-rutinoside, polyphenolic compounds, and antioxidant activity increased. Thus, fermentation improved the functional value of the beverage. The L. casei viability reduced from 9.71 ± 0.04 to 8.90 ± 0.06 log CFU/ mL in the juice with sucrose, and from 9.71 ± 0.04 to 8.71 ± 0.14 log CFU/ mL in the juice with sucralose. Thus, the açaí juice is a viable matrix for the synbiotic food, which allows the viability maintenance during the storage. Regarding sensory acceptance, the internal preference mapping indicated an increase in the color preference with the storage of synbiotic juices. However, the flavor and overall acceptance reduced with storage. Nevertheless, the flavor and overall acceptance of juice with sucralose were better than the juice with sucrose. After 42 days of storage, penalty analysis revealed that beverage with sucrose showed a lack of sweet taste and excess of sour taste. Thus, a high-quality açaí product with viable probiotic microorganism, high anthocyanins, and polyphenolic compounds contents could be obtained, which can be exploited for commercial use. PRACTICAL APPLICATION: Synbiotic açaí juice is a healthier alternative to consuming products containing this fruit. The inclusion of probiotic microorganisms and prebiotic fructooligosaccharides increased bioactive compounds contents during the shelf life of the juice. The sensory evaluation using the internal preference mapping revealed that the juice flavor with sucralose was better accepted than the juice formulated with addition of sucrose.

Storage of beef burgers containing fructooligosaccharides as fat replacer and potassium chloride as replacing sodium chloride.

There was few studies using the simultaneous reduction of fat and sodium chloride, as well as the stability of the meat products with these reductions. This study aimed to evaluate the effects of fat and sodium chloride reduction in beef burgers during storage. For this, two treatments were produced: T1-without fat and sodium chloride reduction (control) and T2-with 50% fat reduction + 5% fructooligosaccharides and with the replacement of 50% of sodium chloride by potassium chloride. Physicochemical analysis and sensory acceptance were performed. According to results, the pH increased (p < 0.05) with 120 days. For the lipid oxidation, there was an interaction between treatments and storage. There was an increase in TBARS with storage for both treatments. T2 had the highest TBARS at 0, 30, and 60 days. For the color before cooking, there was a reduction in the redness (p < 0.05) with 90 days. After cooking, the lightness reduced at 90 days, while the redness increased at 90 days. However, the instrumental changes were not perceived by consumers. For the sensory acceptance, there was a reduction in the flavor, texture and overall liking with storage. However, despite the decline, the averages remained in the acceptance zone. The beef burgers were perceived as less juiciness and less salty after storage. Thus, the storage affects the physicochemical characteristics and sensory evaluation of beef burgers low-fat and low-sodium. The results reinforce the need for more studies with the storage of meat products with fat and sodium chloride reduced.

Aceitação sensorial de iogurte sabor ameixa com e sem lactose / Sensory acceptance of flavored prune yogurt with and without lactose

A lactose possui uma grande importância para a indústria alimentícia, porém existem pessoas que possuem intolerância a este carboidrato. Assim, o objetivo deste estudo foi avaliar a aceitação sensorial de iogurtes com e sem lactose de sabor ameixa. A análise foi conduzida com 60 julgadores não treinados. Para isso, foram utilizadas as escalas hedônica, do ideal e de intenção de compra. Os resultados dos atributos sabor e impressão global da amostra com lactose tiveram maior aceitação (p<0,05). Na escala do ideal, para o atributo sabor de ameixa a maior parte dos julgadores consideraram a amostra com lactose ideal (53,33%). Quanto a doçura, amostra com lactose apresentou maiores valores (63,33%). Assim, ambas amostras obtiveram boa aceitação sensorial e boa intenção de compra. Contudo, o iogurte com lactose teve maior aceitação.

Aceitação sensorial de bebidas lácteas com e sem lactose / Sensory acceptance of dairy beverages with and without lactose

A disponibilidade de produtos que atendam os consumidores com necessidades especiais e aqueles que preferem uma alimentação diferenciada tornam-se necessária devido à demanda crescente. Diante disso, o presente trabalho teve como objetivo avaliar a aceitação sensorial de achocolatados com e sem lactose. A análise foi conduzida com 60 julgadores não treinados. Para isso, foram utilizadas as escalas hedônica e do ideal. De acordo com os resultados obtidos, as bebidas lácteas sabor chocolate com e sem lactose, obtiveram boa aceitação sensorial, tendo todos os atributos avaliados localizados e na região de aceitação da escala hedônica, entre as categorias “gostei ligeiramente” e gostei muito”. Contudo, a bebida láctea com lactose teve maior aceitação quanto aos atributos sabor chocolate, doçura e sabor de leite.

Aceitação sensorial de biscoito de polvilho convencional e light / Sensory acceptance of conventional and light cassava starch biscuit

O sódio está presente na maioria dos produtos industrializados, e seu consumo em excesso pode trazer riscos à saúde. Assim, o presente trabalho teve como objetivo avaliar a aceitação sensorial de biscoito de polvilho convencional e light (com redução de 50% de sódio). Para isso, foi realizada análise sensorial com 60 julgadores não treinados através de escala hedônica e do ideal estruturadas de 9 pontos. De acordo com os resultados obtidos, as amostras de biscoitos de polvilho (convencional e light) obtiveram boa aceitação sensorial, uma vez que os resultados variaram na região de aceitação da escala hedônica entre as categorias “gostei ligeiramente” e “gostei muito”. Contudo, os biscoitos de polvilho convencionais tiveram maior aceitação em relação as amostras light quanto aos termos crocância e sabor salgado.

Aceitação sensorial de cervejas de diferentes marcas comerciais / Sensory acceptance of beers of different trademarks

A cerveja é uma bebida de ampla produção e consumo no mundo, conhecida desde os tempos remotos em diversos países. O presente trabalho teve como objetivo avaliar a aceitação sensorial de cervejas de duas marcas comercializadas na cidade de Imperatriz - MA. A análise sensorial foi conduzida com 60 julgadores não treinados, consumidores de cervejas. Para isso, foram utilizadas as escalas hedônica, do ideal e de intenção de compra. Para os dados de escala hedônica, todos os atributos encontraram-se na região de aceitação da escala, se localizando entre as categorias “gostei ligeiramente” e gostei muitíssimo”. Contudo, a marca B foi mais aceita, em virtude da melhor aparência apresentada. A marca A teve menor aceitação da cor, resultante da menor intensidade desse atributo.

Caracteristicas fisico-quimicas de hamburgueres de frango reduzidos de sal / Physico-chemical characteristics of reduced salt chicken burger

A conscientização dos consumidores esta cada vez maior em relação a ingestão de sódio. Com isso, o objetivo do trabalho foi produzir hambúrgueres de frango com teores reduzidos de sal. Para tanto, foram elaborados os seguintes tratamentos: controle (T1 - com quantidade regular de sal) e T2, T3 e T4 com redução de 15%, 30% e 45% de sal, respectivamente, o qual foi substituído por mix de ervas e especiarias. Os hambúrgueres foram analisados quanto atividade de água, pH e qualidade de cozimento. A atividade de água de T1 foi a menor (p<0,05). Para pH, não foram observadas diferenças entre os tratamentos. A redução de sal não afetou a qualidade do cozimento. Assim, foi possível elaborar hambúrgueres de frango reduzidos de sal com poucas alterações nas características físico-químicas.

Coloração de hamburgueres de frango com redução de sal pelo uso de ervas e especiarias / Chicken burger coloration with salt reduction by the use of herbs and spices

O grande desafio da indústria cárnea é o desenvolvimento de produtos mais saudáveis e que não afetem negativamente as características de qualidade. O objetivo desse trabalho foi produzir hambúrgueres de frango com redução de sal e avaliar sua coloração. Para tanto, foram elaborados os seguintes tratamentos: controle (T1 - com quantidade regular de sal) e T2, T3 e T4 com redução de 15%, 30% e 45% de sal, respectivamente, o qual foi substituído por mix de ervas e especiarias. Os hambúrgueres foram analisados quanto a coloração antes e após a cocção. A coloração de hambúrgueres apresentou mais alterações antes da cocção. A coloração vermelha reduziu com a diminuição de sal, antes do cozimento. A redução de sal a partir de 30% diminuiu a luminosidade e a intensidade de amarelo.

Aceitação sensorial de hambúrguer de frango com reduzido teor de sódio / Sensory acceptance of chicken burger with reduced sodium content

No seguimento de produtos a base de carne, o hambúrguer é um dos mais populares. Dessa forma, esse trabalho visou elaborar hambúrgueres de frango com teor reduzido de sódio. Para tanto, foram elaborados os seguintes tratamentos: controle (T1 – com quantidade regular de sal) e T2, T3 e T4 com redução de 15%, 30% e 45% de sal, respectivamente, o qual foi substituído por mix de ervas e especiarias. Foi avaliada a aceitação sensorial através de escala hedônica e de intenção de compra. De acordo com os resultados, os hambúrgueres de frango com redução de sal e substituição por mix de condimentos apresentaram boa aceitação sensorial. O uso das ervas e especiarias com a redução 15% de sal obteve o melhor desempenho entre os tratamentos avaliados, tornando possível a redução de sódio sem afetar as características sensorial do produto.

Impact of fermentation conditions on the quality and sensory properties of a probiotic cupuassu (Theobroma grandiflorum) beverage.

The aim of the study was to evaluate the conditions of fermentation pH and temperature and also the fermentation time of Lactobacillus casei in the cupuassu (tropical fruit native to the Brazilian Amazon) beverage. The sugars, organic acids, and antioxidant activity during the fermentation also were investigated. The sensory characteristics were also evaluated. Moreover, the effect of expectation on the acceptability of probiotic and symbiotic cupuassu beverages was rated under three conditions. The blind (consumers were informed that the samples were probiotic and symbiotic beverages and they tasted them); expected (only nutritional claims in short text were informed) and informed (consumers were asked to evaluate the product when they had nutritional information). The conditions for probiotic beverage production were initial pH5.8, the temperature of 30°C, and 18h of fermentation. L. casei had viability higher than 9.34LogCFU/mL with 18h of fermentation. The fructose was the most consumed sugar (84.76%), followed by sucrose (62.10%) and glucose (34.52%). The antioxidant activity increased during the fermentation. The organic acids present in the cupuassu (citric, ascorbic and quinic acids) also supported L. casei growth, being consumed during the fermentation improving the nutritional value of the beverage. The acceptance of the probiotic drink increased when the juice was presented to the informed tasters. Therefore, the nutrition claims were effective in increasing the acceptance. The probiotic cupuassu beverage was well accepted as an alternative functional food.

Chemometric evaluation of the volatile profile of probiotic melon and probiotic cashew juice.

The aim of this study was to evaluate the influence of the lactic acid fermentation on volatile compounds of melon and cashew apple juices. The effect of the fermentation processing on the volatile profile of probiotic juices was assessed by HS-SPME/GC-MS coupled to chemometrics with 67.9% and 81.0% of the variance in the first principal component for melon and cashew juices, respectively. The Lactobacillus casei fermentation imparted a reduction of ethyl butanoate, ethyl-2-methylbutirate, and ethyl hexanoate for melon juice; and of ethyl acetate, ethyl-2-methyl butanoate, ethyl crotonate, ethyl isovalerate, benzaldehyde, and ethyl hexanoate for cashew juice. Measurements of the stability of these compounds and the formation of the component 3-methyl-2-butenyl in melon juice may be used as a volatile marker to follow the juice fermentation. These findings suggested that even though it is not a dairy product the lactic acid fermentation of fruits developed a volatile profile combining the fruit and lactic acid fermentation volatiles with mildly formation or degradation of aroma compounds.

Effect of dietary ethanol extracts of mango (Mangifera indica L.) on lipid oxidation and the color of chicken meat during frozen storage.

The aim of this study was to evaluate the dietary effect of mango extracts on lipid stability and the coloring of broiler chicken breast meat during frozen storage. The treatments consisted of broiler chicken diet without antioxidants (control) and diets containing antioxidants: 200 ppm of butylated hydroxytoluene (BHT), 200 ppm of mango peel extract (MPE), 400 ppm of MPE, 200 ppm of mango seed extract (MSE), and 400 ppm of MSE. The broiler breasts were stored for 90 days and analysis of lipid oxidation and color was performed every 30 days. The thiobarbituric acid reactive substances values increased during storage and at 90 days, but the 400 ppm MSE treatment yielded lower values, indicating greater antioxidant activity. During storage, the lightness values decreased and the redness increased. Additions of 200 ppm BHT and 400 ppm MPE increased yellowness at 60 days of storage. Thus, mango peel and seed extracts added to broiler chicken diets reduce lipid oxidation and maintain color in breast meat during frozen storage, with mango seed extract at 400 ppm being the most effective.

Antioxidantes alimentares: importância química e biológica / Dietary antioxidants: chemical and biological importance

During the reduction of molecular oxygen, free radicals or reactive oxygen species are formed and need to be constantly inactivated. Free radicals can damage cell biomolecules, which has been strongly related to aging and to the development of diseases such as cancer and cardiovascular disease. Thus, the presence of efficient scavengers is needed to protect the organism from these substances. Several studies suggest that an increase in the consumption of foods rich in antioxidant nutrients may decreaseor prevent the action of the oxidative processes that occur in the organism. Among the natural antioxidants, fruits and vegetables are the items which most contribute to supply these compounds in the diet. Thus, the action ofantioxidants such as vitamin C, vitamin E, phenolic compounds and carotenoids have stimulated many researches. The aim of the present work is making a literature review about the most important issues concerning the main dietary antioxidants, with an emphasis on their dietary sources and action mechanisms

Durante la reducción del oxígeno molecular seproducen radicales libres o especie reactivas deoxígeno y la necesidad de inactivar estas substancias es permanente. Los radicales libres provocan alteraciones en las moléculas celulares que contribuyen a aumentar el riesgo de cáncer y enfermedades cardiovasculares o disminuyen el número de mitocondrias, que es característico del envejecimiento. Estudios han demostrado que la ingestión diaria de sustancias antioxidantes puede producir una acción protectora efectiva contra los procesos oxidativos que ocurren en el organismo. Entre los antioxidantes naturales, las frutas y los vegetales contribuyen para la suplementación por la dietade compuestos antioxidantes. Así, la acción de los antioxidantes como la vitamina C, la vitamina E, compuestos fenólicos y carotenoides ha sido intensamente estudiada. Este artículo presenta una revisión de la literatura sobre los aspectos más importantes de los principales antioxidantes de la dieta, con enfoque para sus fuentes alimentares y mecanismos de defensa

Durante a redução do oxigênio molecular, radicais livres ou espécies reativas ao oxigênio são formadas e existe a necessidade permanente de inativá-las. Os radicais livres podem ocasionar danos às biomoléculas celulares, o que vem sendo fortemente relacionado ao surgimento de enfermidades, como o câncer, as doenças cardiovasculares e ao processo de envelhecimento. Diversos estudos têm demonstrado que o consumo diário de substâncias antioxidantes na dieta pode produzir uma ação protetora efetiva contra os processos oxidativos que ocorrem no organismo. Entre os antioxidantes naturais as frutas e os vegetais são os alimentos que mais contribuem para o suprimento dietético destes compostos. Dessa forma, a ação de antioxidantes como vitamina C, vitamina E, compostos fenólicos e carotenoides têm estimulado intensa pesquisa. O presente trabalho procurou realizar uma revisão bibliográfica sobre os pontos mais importantes que abrangem os principais antioxidantes dietéticos, com ênfase para as suas fontes alimentares e os seus mecanismos de ação.