Supercritical Carbon Dioxide Extraction of Apigenin from Parsley Leaves Pre-treated to Maximize Yield

Abstract

Apigenin is a bioactive ingredient found in many vegetables and herbs, especially parsley (Petroselinum crispum L.). It was successfully extracted at high yields from parsley leaves using supercritical carbon dioxide (SCCO₂) without co-solvent. A strong correlation was especially apparent at high SCCO₂ density. The amount of extracted apigenin was well correlated with the difference in solubility parameters between the solvent (SCCO₂) and the solute (apigenin). A lower energy requirement for extraction resulted in a greater amount of extracted apigenin. Various pre-treatments of parsley leaves (particle size, drying method and hot-water soaking of the samples) were examined to maximize the amount of extracted apigenin. Soaking in hot-water and then freeze-drying of parsley leaves was an optimal pre-treatment to realize the maximum amount of extracted apigenin.