Eco-friendly extraction and recovery of triterpenoids from persimmon leaves (Diospyros kaki L.f.) using ultrasound-assisted deep eutectic solvents and macroporous resins

Triterpenoids are known for their promising biological activities, and there is a growing focus on green extraction methods for these compounds. In this study, ultrasound-assisted deep eutectic solvents were employed to extract triterpenoids from persimmon leaves, with choline chloride–lactic acid identified as an effective green solvent. The extraction conditions were carefully optimized using response surface methodology, resulting in an extraction efficiency of 12.41%, which is 1.54 times higher than that achieved with conventional organic solvents such as methanol. The triterpenoids were then successfully recovered using a solid–liquid extraction method based on AB-8 macroporous resins, achieving a 94.01% recovery rate with a final product triterpenoid content of 81.87%. These findings provide a strong foundation for the sustainable extraction of triterpenoids and other valuable compounds from biomass.