Extraction of Antimicrobial Substances from Dried Licorice Powder with Supercritical Carbon Dioxide

Abstract

Extraction of antimicrobial substances from dried licorice powder with supercritical carbon dioxide (SC-CO₂) was investigated to yield light color and high activity extract. Recovery of antimicrobial substances was very poor by extraction with pure SC-CO₂, because of their low solubility in SC-CO₂ owing to their high polarity. Supplementation of an entrainer to SC-CO₂ permitted the extraction of antimicrobial substances. The extraction efficiency was closely correlated to the strength parameter of additive entrainers. The antimicrobial substances could be concentrated to more than twice the conventional acetone extract, and its color was appreciably improved.