Dados do Trabalho

Título

RECOVERY OF BIOACTIVE COMPOUNDS FROM GRAPE POMACE USING CONTINUOUS ULTRASOUND-ASSISTED EXTRACTION.

Introdução

Unconventional extraction technologies have been widely studied to improve the recovery of bioactive compounds. The objective of this study was to evaluate the use of ultrasound on the extraction of bioactive compounds from grape pomace from Syrah wine production.

Material e Métodos

50% ethanol solution was used as the extractor solution at a solid:liquid ratio of 1:20. The ultrasonic system was used in re-circulation feed mode. It is equipped with a flow pump and extraction cell with the sonotrode. A central composite design 22 optimization with factorial, central and axial points was elaborated. The independent variables were the pump rate and ultrasound power. A total of 11 assays were carried out and an extraction kinetics of 180' were applied to each one. At points 15', 45', 90', 120' and 180', samples with were removed and centrifuged for 15' at 4,000 rpm and analyzed. The concentration of phenolic compounds (CPC) (Folin-Ciocalteu), monomeric anthocyanins (AC) (differential pH) and antioxidant activity (AA) by the method ABTS and DPPH were evaluated as response variables.

Resultados e Discussão

With regards to the extraction kinetics, it was observed that there was an increase in CPC values from 750.07 ± 18.13 to 1666.11 ± 10.51 mg GAE/100g. The same behavior was observed for AC and AA. The highest values of CPC, AC and AA was verified at 180' of extraction, showing that time can be an important factor. Only the ultrasound power had a significant effect (p > 0.05) on the extraction of bioactive compounds. The values ranged from 883.98 ± 23.44 to 1666.11 ± 10.51 mg GAE/100g for CPC, from 91.53 ± 0.25 to 42.28 ± 0.38 and 65.32 ± 0.22 to 31.58 ± 0.51 µM trolox/g, for ABTS and DPPH, respectively. The preliminary results showed that ultrasound-assisted extraction can be a promise technology for the recovery of bioactive compounds from grape pomace.

Conclusão

The preliminary results showed that ultrasound-assisted extraction can be a promise technology for the recovery of bioactive compounds from grape pomace.