Free radical appears to constitute a particularly promising target for improving the drug treatment of various pathological conditions as cancer, atherosclerosis, and virus infections and in food lipids oxidations. The oxidation can be prevented by adding antioxidants. There is a great interest in plant phenolic compounds because of their potential role as natural antioxidants. Chopé (Gustavia augusta L.) is one fruit from Amazonian that is consumed as food. Chopé samples were dried and submitted to sequential extractions with different solvents. The results showed antioxidant activity in all extracts. Where were identified the following phenolic acids: salicylic, trans-cinamic, hydroxibenzoic, vanilic, cafeic and synaptic. The results obtained are suggesting that the chope extract can be used as antioxidant.

Los radicales libres aparecen como un caso promisorio para incrementar los fármacos para el tratamiento de varias patologías como cáncer, aterosclerosis, infecciones virales y oxidaciones lipídicas. La oxidación puede ser prevenida por la adición de antioxidantes. Existe un gran interés, en los compuestos fenólicos de las plantas debido a su importancia como antioxidantes naturales. El chopé (Gustavia augusta L.), fruta nativa de la región amazónica, la cual se consume como alimento en forma directa. Las muestras de chopé fueron secadas y sometidas a extracciones secuenciales con diferentes solventes. Los resultados demuestran actividad antioxidante en todos los extractos. Se identificó los siguientes compuestos fenólicos: ácidos salicílicos, trans-cinámico, hidroxibenzoico, vinílico, cafeico y sináptico. De los resultados obtenidos se asume que los extractos de chopé pueden ser utilizados muy bien como antioxidantes.

O presente trabalho teve por objetivo apresentar as evidências da atividade antioxidante de extratos aquosos da Halimeda incrassata Ellis Lamoroux obtidos a partir da alga a temperatura ambiente (23°C). A literatura apresenta somente a atividade antioxidante de algas oceânicas associada à frações de carotenóides. Das diferentes espécies de algas oceânicas o extrato aquoso da Halimeda incrassata apresentou a atividade antioxidante mais elevada medida pela inibição da formação de TBARS, durante a peroxidação lipídica espontânea de cérebro, com um C.I.50 de 0,340mg.mL-1. O extrato aquoso da Halimeda incrassata (0,5mg.mL-1), também diminuiu in vitro a formação de peróxido de hidrogênio através de duas vias metálicas envolvendo os ácidos glutâmico e malônico. A Halimeda incrassata (nas doses de 50, 100 e 200mg.Kg-1) apresentou efeito neuroprotetivo in vivo no modelo gerbil de oclusão carótida bilateral, pela diminuição da atividade exploratória e locomotora induzida pela isquemia. Em resumo, o extrato aquoso da Halimeda incrassata apresentou propriedades antioxidantes em diferentes modelos tanto in vitro como in vivo; as quais podem ser atribuídas à presença de diversos compostos hidrossolúveis. Outros estudos são necessários para elucidar as estruturas destes compostos. A baixa toxicidade para humanos de muitas algas oceânicas, particularmente do gênero Halimeda incrassata podem favorecer a sua utilização como alimento funcional.

The aim of the present paper was to provide the evidences for the antioxidant activity in Halimeda incrassata (Ellis) Lamouroux aqueous extracts obtained after simple water extraction of the fresh algae at room temperature (23°C). Previously in the literature, only antioxidant activity associated to carotenoids fractions of seaweeds has been reported. From different species of seaweeds, Halimeda incrassata aqueous extract exhibited the highest antioxidant activity on the inhibition of TBARS formed during the spontaneous lipid peroxidation of rat brain homogenates with an IC50 of 0.340mg.mL-1. Halimeda incrassata aqueous extract (0.5mg.mL-1), was also capable of decreasing the in vitro generation of hydrogen peroxide by two distinct metabolic pathways involving glutamic and malonic acids. Also, Halimeda incrassata (at doses of 50, 100 and 200mg.Kg-1) showed a neuroprotective effect in vivo on the gerbil model of bilateral carotid occlusion because of decreasing the locomotor and exploratory activity induced by ischemia. In summary, Halimeda incrassata aqueous extracts exhibit antioxidant properties in different in vitro as well as in vivo models which could be explained by the presence of several hydrosoluble compounds. Further studies on this way are necessary to elucidate the precise structure of these compounds. Low toxicity of most seaweeds to humans, but particularly of Halimeda genus may favor its use as functional food.

The correlation between dietary trans fatty acids and neoplasia was examined in the present study. Walker 256 tumor-bearing and control rats were fed a trans monounsaturated fatty acid (MUFA)-rich diet for 8 weeks and the incorporation of trans fatty acids by tumor tissue was examined. Also, the effect of tumor growth on trans fatty acid composition of plasma and liver, and the content of thiobarbituric acid-reactive substances (TBARS) was determined. Walker 256 tumor cells presented both trans and cis MUFAs given in the diet. The equivalent diet proportions were 0.66 for trans and 1.14 for cis. Taking into consideration the proportion of trans MUFAs in plasma (11.47%), the tumor incorporated these fatty acids in a more efficient manner (18.27%) than the liver (9.34%). Therefore, the dietary trans fatty acids present in the diet are actively incorporated by the tumor. Tumor growth itself caused marked changes in the proportion of polyunsaturated fatty acids in the plasma and liver but provoked only slight modifications in both trans and cis MUFAs. Tumor growth also reduced the unsaturation index in both plasma and liver, from 97.79 to 86.83 and from 77.51 to 69.64, respectively. This effect was partially related to an increase in the occurrence of the lipid oxidation/peroxidation process of TBARS content which was increased in both plasma (from 0.428 to 0.505) and liver (from 9.425 to 127.792) due to tumor growth.

Spirulina maxima, which is used as a food additive, is a microalga rich in protein and other essential nutrients. Spirulina contains phenolic acids, tocopherols and ß-carotene which are known to exhibit antioxidant properties. The aim of the present study was to evaluate the antioxidant capacity of a Spirulina extract. The antioxidant activity of a methanolic extract of Spirulina was determined in vitro and in vivo. The in vitro antioxidant capacity was tested on a brain homogenate incubated with and without the extract at 37oC. The IC50 (concentration which causes a 50% reduction of oxidation) of the extract in this system was 0.18 mg/ml. The in vivo antioxidant capacity was evaluated in plasma and liver of animals receiving a daily dose of 5 mg for 2 and 7 weeks. Plasma antioxidant capacity was measured in brain homogenate incubated for 1 h at 37oC. The production of oxidized compounds in liver after 2 h of incubation at 37oC was measured in terms of thiobarbituric acid reactant substances (TBARS) in control and experimental groups. Upon treatment, the antioxidant capacity of plasma was 71% for the experimental group and 54% for the control group. Data from liver spontaneous peroxidation studies were not significantly different between groups. The amounts of phenolic acids, <FONT FACE="Symbol">a</FONT>-tocopherol and ß-carotene were determined in Spirulina extracts. The results obtained indicate that Spirulina provides some antioxidant protection for both in vitro and in vivo systems.

Foram avaliadas as seguintes características físicas: densidade, água absorvida e tempo de cocção de 33 cultivares de feijão guandu. A densidade ficou estável durante o armazenamento entre os cultivares. A relação entre a massa hidratada pela massa inicial foi acima de 2,0 até aos 6 meses para a maioria dos cultivares sendo que aos 9 meses tivemos algumas cultivares que não atingiram relação acima de 2,0 e aos 12 meses somente 2 cultivares atingiram relação 2,0. A relação do tempo de cocção inicial pelo tempo de cocção em diferentes tempos demonstrou comportamentos distintos entre os cultivares, sendo que os cultivares L-16 e L-14 apresentaram as maiores relações entre o tempo inicial e o período de 12 meses de armazenagem. .Por esses resultados, pôde-se observar a grande variabilidade das características físicas dos diferentes cultivares estudados. No entanto houve a possibilidade de selecionar as cultivares L-03; L-09; L-29; L-30 e L-36 por apresentarem maior estabilidade frente ao tempo de armazenamento.

Physical characteristics as density, water absorbed, and cooking time of 33 cultivars of guandu beans were evaluated. Density was stable during storage among cultivars. The ratio between the initial hydrated mass was over 2.0 until 6 months for most cultivars and the ratio of some cultivars failed to reach over 2.0 at 9 months and at 12 months only 2 cultivars reached a 2.0 ratio. The ratio of initial cooking time to the cooking time at different times showed distinct behavior among cultivars and cultivars L-16 and L-14 had the highest ratios between initial time and a 12-month storage period. These results showed the great variability of the physical characteristics of the varied cultivars studied. Cultivars L-03, L-09, L-29, L-30, and L-36, however, were likely to be selected due to their higher stability concerning storage time.