Ultrasonically enhanced extraction of luteolin and apigenin from the leaves of Perilla frutescens (L.) Britt. using liquid carbon dioxide and ethanol.

The present study reports on the ultrasonic enhancement of the liquid carbon dioxide (CO2) extraction of luteolin and apigenin from the leaves of Perilla frutescens (L.) Britt., to which ethanol is added as a cosolvent.