Multi-Optimization of Ultrasonic-Assisted Enzymatic Extraction of Atratylodes macrocephala Polysaccharides and Antioxidants Using Response Surface Methodology and Desirability Function Approach

Rhizoma Atractylodes macrocephala polysaccharides (RAMP) have been reported to have a variety of important biological activities. In this study, an ultrasonic-assisted enzymatic extraction (UAEE) was employed to obtain the highest extraction yield and strongest antioxidant activity of RAMP and optimized by a multi-response optimization process. A three-level four-factor Box-Behnken design (BBD) was performed as response surface methodology (RSM) with desirability function (DF) to attain the optimal extraction parameters. The DPPH scavenging percentage was used to represent the antioxidant ability of RAMP. The maximum D value (0.328), along with the maximum yield (59.92%) and DPPH scavenging percentage (13.28%) were achieved at 90.54 min, 57.99 °C, 1.95% cellulase and 225.29 W. These values were further validated and found to be in good agreement with the predicted values. Compared to the other extraction methods, both the yield and scavenging percentage of RAMP obtained by UAEE was favorable and the method appeared to be time-saving and of high efficiency. These results demostrated that UAEE is an appropriate and effective extraction technique. Moreover, RSM with DF approach has been proved to be adequate for the design and optimization of the extraction parameters for RAMP. This work has a wide range of implications for the design and operation of polysaccharide extraction processes.