A green approach for the extraction and characterization of oridonin and ursolic and oleanolic acids from Rabdosia rubescens and its kinetic behavior.
An ultrasound-assisted supercritical carbon dioxide (USC-CO2) procedure was developed for the extraction of ursolic acid, oleanolic acid and oridonin from Rabdosia rubescens, with yields that were 9.84-10.46 and 15.43-21.10% higher than those of the conventional SC-CO2 and heat-reflux extractions, respectively. USC-CO2 uses a shorter extraction time (1.83-2.09 times) and less organic solvent (3.39-173.25 times) to operate at a lower extraction temperature (5-16 °C). The dominant component in the extract was oridonin, which may indicate that the kinetic behavior in the extraction system is predominated by that of oridonin. Furthermore, the USC-CO2 and conventional SC-CO2 dynamic extraction kinetics of oridonin from R. rubescens were well described by the second-order rate and Fick's second law models. The extraction rate constant, energy of activation for diffusion, Biot number and thermodynamic parameters were deduced from the data obtained. These results provide valuable insights into the USC-CO2 and conventional SC-CO2 procedures.
['Yang|Yu-Chiao|YC|', 'Wang|Chia-Sui|CS|', 'Wei|Ming-Chi|MC|']
D002245:Carbon Dioxide D005591:Chemical Fractionation D002851:Chromatography, High Pressure Liquid D045786:Diterpenes, Kaurane D055772:Green Chemistry Technology D037602:Isodon D007700:Kinetics D009828:Oleanolic Acid D010936:Plant Extracts D010946:Plants, Medicinal D015203:Reproducibility of Results D012997:Solvents D053719:Tandem Mass Spectrometry D014315:Triterpenes D014465:Ultrasonics
Oridonin Oleanolic acid Rabdosia rubescens Ursolic acid Thermodynamic parameters Diffusion model Second-order rate model Ultrasound-assisted supercritical CO(2) extraction