Equilibrium on reactive extraction of glabridin in a quaternary solvent system containing SBE-β-CD.

Glabridin has important bioactivities in anti-cellular aging, anti-atherosclerosis, protecting the nervous system and inhibiting melanin. There is currently no efficient separation method for the large-scale production of high-purity glabridin due to its insolubility in water. This paper presents hydrophilic β-cyclodextrin derivatives for the reactive extraction of hydrophobic glabridin from organic phase to aqueous phase in a quaternary solvent extraction system. The variables that affect extraction efficiency were studied, including solvent type, extractant type and concentration, extraction time and temperature. The optimal extraction conditions were achieved, involving extractant of SBE-β-CD, water-ethanol (5:5, v:v)/n-octanol-n-hexane (3:7, v-v) as extraction system and temperature of 5 degree. The results show that SBE-β-CD has a strong inclusion capacity for glabridin with inclusion constants of 85.95 L/mol. The reactive extraction reaches equilibrium in five minutes, which is convinced to fractional extraction. It is a promising method for the large-scale selective separation of high-purity glabridin from crude extract of Glycyrrhiza glabra. • A quaternary solvent extraction system was explored to separate glabridin. • SBE-β-CD was used as extractant for reactive extraction of hydrophobic glabridin. • The extractant SBE-β-CD is safe and environmentally friendly. • Short reaction equilibrium time, and the technology has broad application prospects. [ABSTRACT FROM AUTHOR]