Optimization of ultrasonic-assisted extraction and purification of flavonoids with biological activities from Ficus Pumila L.

To optimize the extraction process and activity detection of total flavonoids from Ficus Pumila, a Box-Behnken design of response surface methodology was employed to further optimize ultrasonic-assisted extraction (UAE) conditions for F. Pumila stems total flavonoids (FPSTF). The results showed that optimized extraction conditions were ultrasonic power of 240 W, solvent concentration of 61%, ultrasonic time of 61 min, and liquid-solid ratio of 25 mL/g. Under these conditions, the mean experimental value of extraction yield (1.07%) was achieved, which was about 2.14 times that of ethanol leaching extraction. As compared with FPSTF, FPSTF after purification (FPSPTF) had higher purity of 11.09%, which was nearly 4.37 times higher than that of FPSTF(2.54%). As compared with FPSTF, FPSPTF had higher alpha-glucosidase and alpha-amylase inhibitory activities as well as DPPH center dot and ABTS center dot(+) scavenging activities with an IC50 value of 0.005, 0.008, 0.22, and 0.08 mg/mL, which was 6.00, 16.50, 1.68, and 2.50 times higher than that of FPSTF (0.030, 0.132, 0.37, and 0.20 mg/mL), respectively. FPSPTF from F. Pumila could be considered as a multifunctional bioactive ingredient to be used in anti-hyperglycemic pharmaceutical formulation and antioxidant.