Ultrasound-assisted extraction of phenolic compounds from Macela (Achyrolcine satureioides) extracts

Abstract

Achyrocline satureioides or Macela, a native plant from South America, has been studied due to its potential antioxidant activity. This study sought to optimize the conditions for extraction of the bioactive compounds from Macela. The solvents 50% (v/v) acetone and 70% (v/v) ethanol were selected from preliminary assays, for a comparison study. The application of ultrasound for the extractions increased the amount of total phenolic compounds by 6.1-fold and the antioxidant activity by 3.4-fold compared with conventional extraction. Principal component analysis revealed that both solvents did not present statistical differences in the extractions, although the liquid chromatography analysis showed that relative to ethanol, the acetone extracts had a higher amount of quercetin, the major flavonoid present in Macela plants. Therefore, the best ultrasound-assisted extraction condition for both solvents studied was a temperature of 25 °C and a 1:40 solute:solvent ratio (w/v), independent of the extraction time (10, 50 or 90 min).