Suchergebnisse

The aim of this work was to investigate the possibility of combination between micro-waves and ultra-sounds in order to determinate their impact on quality parameters, antioxidant capacity and phenolic compounds as well as fatty acid composition. The protocol consisted in microwave followed by a sonication treatment of olive paste for 5, 10 and 15 min. Results showed that the total phenolic content of olive oil increased positively with the increasing time of treatment ranging from 356 to ~ 639 mg GAE.kg−1 of olive oil. On the other hand, the fatty acid profiles of all studied oils were determined by GC-FID. Besides, olive oil obtained after 15 min of microwave olive past treatment followed by 10 or 15 min of ultrasound treatment showed that these oils had the highest value of Z-vaccenic (C18:1n-7) + Oleic (C18:1n-9) acids. These results encourage further developments for a combined continuous microwave and ultrasonic conditioning technology to fasten the olive oil extraction, to enhance total phenolic, chlorophyll as well as carotenoid contents and Fatty acid composition.

This study was designed to optimize maceration (ME) and ultrasound-assisted extraction (UAE) parameters (extraction time X1, temperature X2, solvent/mass Ratio X3 and Ethanol concentration X4) of antioxidant activity of Eucalyptus marginata L. leaves' using response surface methodology (RSM). The antioxidant activity was evaluated using the DPPH assay and ferric reducing antioxidant power (FRAP). The optimal conditions for ME and UAE of antioxidant compounds were: X1 (min) = 88 and 50, X2 (°C) = ~75 and ~79, X3 (ml/g) = 40 and 39.5 and X4 (% of ethanol) = 59.65 and 58.48, respectively. Consequently, these optimized ME and UAE methods have shown a potential application for the efficient extraction of polyphenolic antioxidants from Eucalyptus marginata L. by-products in several industries including nutraceutical and pharmaceutical.