Optimization of ultrasonic-assisted extraction and purification of flavonoids from Sophora japonica L. with macroporous resins

Rutin and flavonoids derived from Sophora japonica hold significant potential for various bioactivities. The objective of this study is to improve the ultrasonic-assisted extraction procedure for obtaining rutin and total flavonoids from Sophora japonica. Moreover, the purification of these total flavonoids from the ethanol extract was accomplished using macroporous resins. Under optimal conditions, the extraction efficiency of rutin and total flavonoids were 32.49% and 48.40%, respectively. Out of the 11 macroporous resins tested for purification, the results indicated that DAX-8 and ADS-7 were the two most efficient resins. Under meticulously optimized purification conditions, the highest flavonoid content attained in the final product was 93.13% for DAX-8 and 92.20% for ADS-7, respectively. Based on the findings, the extraction and purification technique explored in this research provides a solid basis for improving industrial procedures related to extracting and purifying flavonoids from Sophora japonica.