ABSTRACT
Seis pulpas de frutas tropicales de origen colombiano: curuba (Passiflora tripartida var. Mollissima), gulupa (Passiflora edulis Sims), aguacate variedad Hass (Persea America Mill), lulo (Solanum quitoense Lam.), tomate de árbol (Cyphomandra betacea Sendt) y uchuva (Physalis peruvianaL) fueron empleadas para realizar el estudio del contenido total de fenoles, por el método de Folin Ciocalteu y la actividad antioxidante por los métodos químicos: DPPH (2,2-difenil-2-picrilhidrazilo) y FRAP (poder antioxidante para reducir iones férricos), y por los métodos biológicos: oxidación de lipoproteínas de baja densidad (LDL) e inhibición del estrés oxidativo sobre el crecimiento de Saccharomyces cerevisiae. Se encontró que el extracto de curuba presentó el mayor contenido total de fenoles con un valor de 683,48 ± 18,48 mg equivalentes de ácido gálico/100 g muestra B.H. (Base Húmeda). En cuanto a los ensayos de actividad antioxidante el extracto de aguacate presentó mayor actividad por el método DPPH con un valor de 165,10 ± 4,36 µmol Trolox/100 g muestra B.H., mientras que el extracto de curuba presentó la mayor actividad antioxidante por el método FRAP con un valor de 148,07 ± 12,07 µmol Trolox/g muestra B.H. En el ensayo de oxidación de LDL los extractos de curuba y uchuva presentaron la mayor capacidad de inhibición en la oxidación de dichas lipoproteínas con un valor de 1,61 ± 0,01 y 1,46 ± 0,06 nmol TMP (Tetrametoxipropano)/g muestra B.H., respectivamente. En el ensayo de inhibición del estrés oxidativo sobre el crecimiento de S. cerevisiae los extractos de aguacate, curuba y gulupa tuvieron el mayor efecto protector obteniéndose una concentración celular de.
Six pulp extracts of tropical fruits from Colombia: banana passion fruit (Passiflora tripartida var. Mollissima), gulupa (Passiflora edulis Sims), avocado (Persea americana Mill.), lulo (Solanum quitoense Lam.), tomate de árbol (Cyphomandra betacea Sendt.), and gooseberry (Physalis peruviana L.) were used for studying the total phenolic content by the Folin Ciocalteu method and the antioxidant activity by the chemical methods: DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric ion reducing antioxidant power), and by the biological methods: oxidation of low density lipoproteins (LDL) and inhibition of oxidative stress on Saccharomyces cerevissiae growth. It was found that banana passion fruit extract showed the highest content of total phenolics, with a value of 683.48 ± 18.48 mg equivalents to gallic acid/100 g fresh weight (F.W.). Regarding the antioxidant activity the avocado extract exhibited the highest activity in the DPPH assay, with a value of 165.10 ± 4.36 µmol Trolox/100g F.W. whereas the banana passion fruit extract showed the highest antioxidant activity by the FRAP method, with a value of 148.07 ± 12.07 µmol Trolox/g F.W. In the LDL oxidation assay the extracts from banana passion fruit and gooseberry presented the greater ability to inhibit the oxidation of those lipoproteins, with a value of 1.61 ± 0.01 and 1.46 ± 0.06 nmol TMP (Tetrametoxipropane)/g F.W., respectively. In the assay of inhibition of oxidative stress on S. cerevissiae the avocado, banana passion fruit, and gulupa extracts exhibited the main protective effect and the obtained values for cellular concentration were 1.96 ×10(7) cells/mL, 1.86 × 10(7) cells/mL, and 1.54 × 10(7) cells/mL, respectively, as compared to 0.99 × 10(7) cells/mL found.
Seis polpa de frutas tropicais da Colômbia: maracujá (Passiflora tripartite Mollissima var.), Gulupa (Passiflora edulis Sims), Hass abacate (Persea América Mill), lulo (Solanum quitoense Lam.), tomate de árvore (Cyphomandra betacea Sendt) e uchuva (Physalis Peruviana L) foram utilizados para o estudo do teor total de fenol pelo método de Folin-Ciocalteu e actividade antioxidante por métodos químicos: DPPH (2,2-difenil-2-picrilhidrazilo) e FRAP (poder antioxidante de reduzir iões férricos), e métodos biológicos: a oxidação de lipoproteínas de baixa densidade (LDL) e inibição de estresse oxidativo no crescimento de Saccharomyces cerevisiae. Os resultados são encontrados no extrato tiveram o maior teor total maracujá de fenóis com um valor de 683,48 ± 18,48 mg equivalentes o ácvido gálico/100 g amostra de ácido BH (Base úmida). Quanto à atividade antioxidante testes abacate extrato apresentou maior atividade com o método DPPH vale 165,10 ± 4,36 µmol Trolox / 100g de amostra BH, enquanto o extrato de maracujá apresentou a maior atividade antioxidante, método FRAP com um valor de 148,07 ± 12,07 µmol Trolox/g amostra BH. No ensaio de oxidação de LDL e extrai maracujá e uchuva teve a maior capacidade para inibir a oxidação de lipoproteínas estes com um valor de 1,61 ± 0,01 e 1,46 ± 0,06 nmol TMP (tetrametoxipropano)/g BH amostra, respectivamente. No ensaio de inibição de estresse oxidativo no crescimento de S. cerevisiae de extratos de abacate, maracujá e gulupa tinha o maior efeito protector sendo obtido uma concentração de células de 1,96 ×10(7) células/mL, 1,86 × 10(7) células/ml e 1,54 × 10(7) células/mL, respectivamente, em comparação com aqueles encontrados.
ABSTRACT
Aims: Evaluation of three extraction methods to prepare bioactive-rich ginger extract for incorporation into a functional beverage. Study Design: Response surface methodology. Methodology: For the preparation of bioactive-rich ginger extract with water, conventional hot water extraction, ultrasonic-assisted extraction and high pressure homogenization-assisted extraction were evaluated. Response surface methodology was employed to optimize the extraction conditions of each method with respect to the highest polyphenols, antioxidant capacity (ferric reducing antioxidant power; FRAP) and percent inhibition of low density lipoprotein (LDL) cholesterol oxidation. Results: Multiple response optimizations revealed that the optimum extraction conditions for each extraction method were 60min extraction time under 55°C for hot water extraction, 15min ultrasonication under 52°C for ultrasonic-assisted extraction and 62°C under 140MPa homogenization pressure for high pressure homogenization-assisted extraction. Conclusion: The extract prepared from the ultrasonic-assisted extraction method exhibited the highest polyphenol recovery and antioxidant activity, compared to the extracts prepared from other two methods.
ABSTRACT
The antioxidant effect of 5-Aminosalicylic acid (5-ASA) on copper-mediated LDL oxidation was followed either by the emitted chemiluminiscence (CL) or by UV-vis spectroscopy. 5-ASA addition extends the lag phase in a concentration-dependent manner without changes in the rate of the process in the autoaccelerated phase. The antioxidant behavior of 5-ASA was very similar to that of Trolox, a very efficient water soluble antioxidant. The copper-binding capacity of 5-ASA was evaluated by UV-visible spectroscopy. The addition of copper to a 5-ASA solution increases the absorbance at 332 nm and generates a new band at 298 nm. These changes in the UV-vis spectra indicate formation of a complex between 5-ASA and copper. However, LDL protection by 5-ASA is unrelated to its copper chelating capacity.