Optimization of Ultrasonic-assisted Extraction of Antioxidant Compounds from Asari Radix et Rhizoma Using Response Surface Methodology / 中国药学杂志

ABSTRACT

OBJECTIVEP To investigate ultrasonic-assisted estraction(UAE) and response surface methodology(RSM) for the extraction of asarinin from Asari Radix et Rhizoma(ARR). METHODS: The RSM was based on a three-level, four-variable Box-Behnken design (BBD). The independent variables were ultrasonic time, liquid to solid ratio, ultrasonic temperature, and ultrasonic power, the dependent variable was extraction rate of asarinin, which was used to estimate the relationship between independent and dependent variables. Box-Behnken design and RSM were used to optimize the process of extraction. The prediction was carried out through comparing the observed and predicted values. Antioxidant activity of the extract of ARR was determined by 1,1-diphenyl-2-trinitrophenylhydrazine(DPPH) and 2, 2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate(ABTS) radical scavenging assays in vitro, and good correlation between extraction rate of asarinin and antioxidant activity was observed. RESULTS: The results indicated that ultrasonic time, liquid to solid ratio, ultrasonic temperature, and ultrasonic power had a significant effect on extraction rate of asarinin. Overall process intensification was achieved with ultrasonic time of 56 min, liquid to solid ratio of 171 mL•g-1, ultrasonic temperature of 52℃, and ultrasonic power of 180 W by UAE method. Under optimal conditions, the yield of asarinin was (1.55±0.32) mg•g-1 (n=3), which was in accordance with the predicted yield of 1.58 mg•g-1. The IC50 values of the extract of ARR sample were 29.701 and 64.643 mg•mL-1, respectively. The antioxidant results indicate that the extract of ARR has excellent ability to scavenge free radicals and antioxidant capacity and is expected to be used as a natural antioxidant in industrial applications. CONCLUSION: The extraction technology is simple, reliable and highly predictive.The UAE method is effective for extraction of asarinin from ARR.