3 resultados para Activity concentration correction
em Universidad Politécnica de Madrid
Resumo:
Palm juice (Borassus flabellifer) is one of the most common and cheap natural juices. Fermented palm juice contains various phytochemical compounds that exhibit antioxidant activity. In the present study, we examined the effects of pH on the production of phytochemicals and their antioxidant activity during the fermentation process. The concentration of total phenolics and flavonoid compounds of fermented palm juice and their antioxidant activity were investigated at various pH. The results showed that total phenolics concentration and antioxidant activity of palm wine and palm vinegar increase as pH increases: 3.54.55.5. Maximum flavonoid concentration was obtained at pH 6.5. Measurements of antioxidant activity by conventional DPPH method and Photochem antioxidant analyzer technique were highly correlated, with a corresponding R2 value of 0.94.
Resumo:
The study examined the effect of xylanase supplementation on apparent metabolizable energy (AME) and hepatic vitamin E and carotenoids in broiler chickens fed wheat based diets. A total of one hundred forty four male Ross 308 chickens were used in this study. Birds were randomly assigned to 3 dietary treatments (8 cages per treatment of 6 male broilers each) for 14 days from 7 to 21 day old. The control treatment was based on wheat-soyabean meal and was either unsupplemented or supplemented with either 1000 or 2000 xylanase units per kg diet. Orthogonal polynomial contrasts were used to test linear response to dietary xylanase activity. There was a positive linear relationship (P < 0.05) between dietary AME and doses of supplementary xylanase. A linear relationship (P < 0.05) was also observed between dosage of xylanase supplementation and hepatic vitamin E concentration and retention. In conclusion, xylanase supplementation improved dietary AME and increased hepatic vitamin E concentration which may have positive effects on the antioxidative status of the birds.
Resumo:
This study focuses on the relationship between CO2 production and the ultimate hatchability of the incubation. A total amount of 43316 eggs of red-legged partridge (Alectoris rufa) were supervised during five actual incubations: three in 2012 and two in 2013. The CO2 concentration inside the incubator was monitored over a 20-day period, showing sigmoidal growth from ambient level (428 ppm) up to 1700 ppm in the incubation with the highest hatchability. Two sigmoid growth models (logistic and Gompertz) were used to describe the CO2 production by the eggs, with the result that the logistic model was a slightly better fit (r2=0.976 compared to r2=0.9746 for Gompertz). A coefficient of determination of 0.997 between the final CO2 estimation (ppm) using the logistic model and hatchability (%) was found.