ABSTRACT
Abstract This study was aimed at optimizing the ultrasound-assisted extraction (UAE) of phenolic compounds from jussara and blueberry fruits using the response surface methodology (RSM). UAE was found to be more efficient to extract phenolic compounds from both fruits than the conventional extraction. The optimum extraction conditions for the jussara fruits were: extraction time between 30 and 62 min for total anthocyanins and total phenolics, fruit:solvent ratio of 10% and 6% (w/v) for total anthocyanins and total phenolics, respectively. The ethanol concentration was non-significant (p> 0.05). Acidified water was found to be an extracting solvent as efficient as ethanol in the extraction of phenolic compounds from jussara fruits. The optimum extraction conditions for blueberry anthocyanins were: ethanol concentration between 20-70% vol, and fruit: solvent ratio greater than 20% (w/v) within the range studied. The extraction time was not significant (p> 0.05). For total phenolic content: the concentration of ethanol was between 40-80%, and fruit: solvent ratio greater than 20% (w/v) and extraction time over 50 minutes. It was possible to adjust the mathematical model for the coordinates a* (verde vs vermelho) and C* (color saturation) of the jussara extracts.
ABSTRACT
RESUMO: O objetivo deste trabalho foi avaliar a influência do tipo de cultivo (ambiente seco e alagado) sobre o teor de vitamina C, β-caroteno e minerais (cálcio, magnésio, enxofre, zinco, ferro, manganês, cobre, boro, nitrogênio, fósforo e potássio) de camu-camu. As vitaminas citadas foram determinadas por cromatografia líquida de alta eficiência, enquanto que os minerais cálcio, magnésio, zinco, cobre, manganês e ferro por espectrometria de absorção atômica, o potássio por fotometria de chama e o fósforo, boro e enxofre por espectrofotometria, nos comprimentos de onda 725 e 420nm, respectivamente. O fruto cultivado em ambiente seco apresentou maior (P<0,05) teor de vitamina C (13.756,79mg 100g1/peso seco) e da maioria dos minerais investigados (cálcio, magnésio, enxofre, ferro, cobre, nitrogênio, fósforo e potássio). Os teores de β-caroteno não variaram (P>0,05) em função dos diferentes ambientes.
ABSTRACT: The aim of this study was to evaluate the influence of crop type (dry and flooded environment) on vitamin C, β-carotene and minerals (calcium, magnesium, sulfur, zinc, iron, manganese, copper, boron, nitrogen, phosphorus and potassium), of camu-camu content. Vitamins were determined by high performance liquid chromatography, calcium, magnesium, zinc, copper, manganese and iron by atomic absorption spectrometry, potassium by flame photometry and phosphorous, boron and sulfur by spectrophotometry in wave lengths 725 and 420nm, respectively. Fruit grown in a dry environment showed higher (P<0.05) vitamin C content (13756.79mg 100g-1/dry weight) and generally higher mineral content (calcium, magnesium, sulfur, iron, copper, nitrogen, phosphorus and potassium). β-carotene content was not influenced (P>0.05) by different environments.