Ultrasound as an alternative technology to extract carotenoids and lipids from Heterochlorella luteoviridis

The present work evaluated the use of ultrasound as a pre-treatment to lipid and carotenoid extraction from the microalgae Heterochlorella luteoviridis. The pre-treatment was performed in the presence of ethanol (25%, v/v) with the ultrasound intensity varying from 0 to 100% (435 kJ kg−1). After the pre-treatment, a diffusive step was performed in order to evaluate different ethanol concentrations (50-75%, v/v). The results regarding carotenoid extraction showed that there is an optimal extraction region: 40-80% of ultrasound intensity and 60-75% of ethanol concentration. The lipid extraction was not influenced by the ultrasound pre-treatment and increased with the increase of ethanol concentration.