Solubility of carnosic acid and carnosol from rosemary extract in supercritical $CO_2$

Rosemary leaves extract are known to have significant antioxidant properties and are widely used in foods and nutritional supplements. Compounds responsible for these antioxidant properties are mainly the phenolic diterpenes. The major phenolic diterpenes are carnosic acid and carnosol. Much interest has been focused on the isolation of carnosic acid, due to its wide spectrum of actions and beneficial effects on human health. In this work a natural rosemary extract, containing 73.9% carnosic acid and 14.7% carnosol, was investigated regarding the solubility of carnosic acid and carnosol in supercritical $CO_2$. The solubility measurements, using a static-analytic method, were performed at temperatures 40, 60 and 80 °C and at pressures ranging from 98 to 402 bar. The Chrastil model was used to correlate the obtained experimental solubility data.