Application of ultrasound-assisted processing in improving the purification effect and bioactivity of licorice flavonoids from licorice residues

Abstract

Licorice residues are rich in flavonoids and are considered to be valuable reusable resources with broad applications and a high economic value. In view of above, the ultrasound-assisted adsorption/desorption of licorice flavonoids (LFs) on HPD-100 resins was studied. This process was studied at different temperatures (20–30 ℃) using ultrasound at different power densities (0.2, 0.35, 0.5 W/cm2). The higher ultrasonic power density (0.5 W/cm2) and lower temperature (20 ℃) facilitated the adsorption process. The ultrasonic power density of 0.5 W/cm2 and the temperature of 30 ℃ were favorable for the desorption process. The adsorption behavior can be well described by the pseudo second-order kinetic model. It was illustrated that the ultrasonic power density was 0.5 W/cm2, the recovery of ultrasonic assisted adsorption/desorption of LFs was 9.99 % higher than that without ultrasonic treatment. Interestingly, licochalcone A (LicA) had the highest adsorption capacities, while the desorption capacities of liquiritigenin was the highest. In addition, it was worth mentioning that the activities of LFs were increased with the enhancement of the ultrasonic power density. Furthermore, it was demonstrated that LFs had a protective effect on the injury and apoptosis of H9c2 cardiomyocytes induced by H2O2. The underlying mechanism may be interrelated with the activation of Nrf2/HO-1 pathway.