To enable the effi cient extraction of ursolic acid, a non-polar bioactive compound, the applicability of alcohol-based deep 

eutectic solvents (DESs) was investigated. A series of DESs were prepared by combining a fi xed hydrogen bond acceptor, 

choline chloride (ChCl), with various hydrogen bond donors (HBDs) such as glycerol, ethylene glycol, 1,3-propanediol, 

1,2-propylene glycol, and 1,4-butanediol at diff erent molar ratios. To evaluate their potential as green solvents, the cytotoxicity

of the alcohol-based DESs was assessed, and the 1,2-propylene glycol-based DESs exhibited the lowest cytotoxicity. 

Due to the high viscosity of DESs, direct solubility measurements of ursolic acid were limited; thus, the COSMO-SAC 

model was employed to predict solubility and guide the screening of suitable DESs. Computational results suggested that 

DESs containing 1,2-propylene glycol and 1,4-butanediol provided superior solubility for ursolic acid. Based on both cytotoxicity

and predicted solubility, the DES composed of ChCl and 1,2-propylene glycol at a 1:4 molar ratio was identifi ed 

as the most biocompatible solvent system. Using this DES, ursolic acid was successfully extracted from rosemary and 

apple peel. Experimental validation confi rmed that PG-based DES (ChCl:1,2-propylene glycol = 1:4) exhibited a solubility 

70% lower for ursolic acid than pure ethanol. This study supports a strategic shift toward sustainable extraction technologies

using DESs and provides a foundation for future research on their industrial applicability.