Extraction of Glabridin from Glycyrrhiza glabra L. root using ethanol modified supercritical CO2: RSM optimization and mathematical modeling

Document Type : Research Article

Authors

1 Iranian Research Organization for Science and Technology (IROST), Department of Chemical Technologies, Tehran, Iran

2 Department of Chemical Engineering, Isfahan University of Technology, Isfahan, Iran

Abstract

In this study, supercritical fluid extraction (SFE) of glabridin (GB) from licorice (Glycyrrhiza glabra L.) roots was carried out using CO2 as the solvent and ethanol as a co-solvent. Response surface methodology (RSM) was employed for the design of experiments (DOEs), modeling and optimization of GB extraction recovery. Temperature (40-80 °C), pressure (8-24 MPa), CO2 flow rate (0.5-2.5 ml/min) and dynamic extraction time (20-100 min) were considered as independent operating variables. At all experiments the static extraction time and co-solvent flow rate were kept constant at 30 min and 5 vol. % of the CO2 flow rate, respectively. The GB content in the extracted samples was quantified using high-performance liquid chromatography (HPLC). The maximum extraction recovery of 60±2% was obtained at the optimal conditions of 40 °C, 24 MPa, 1.8 ml CO2/min and 76 min. The isotherms of GB recovery were also obtained as a function of time at 24 MPa and a CO₂ flow rate of 1.8 mL min⁻¹. Moreover, a mechanistic mass-transfer model incorporating solid-fluid equilibrium, interphase mass transfer, axial dispersion and intraparticle diffusion was developed to describe the extraction kinetics. The developed model successfully predicted the experimental data with an overall average absolute relative deviation (AARD) of approximately 4.2%.

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Articles in Press, Accepted Manuscript
Available Online from 07 February 2026
  • Receive Date: 29 December 2025
  • Revise Date: 01 February 2026
  • Accept Date: 07 February 2026
  • First Publish Date: 07 February 2026
  • Publish Date: 07 February 2026