Optimization Of Extraction Of Gastrodin From Rhizoma Gastrodia By Response Surface Methodology

Objective:The aim of the study was to explore the optimum processes of extraction gastrodine from Rhizoma gastrodiae by ultrasonic and microwave.Methods:With the content of gastrodine as index, HPLC was used to determine gastrodin content. Factors influencing ultrasonic and microwave extraction of gastrodine from Rhizoma Gastrodiae was studied by one-factor tests. The effects of material/liquid ratio (g/mL), extraction temperature,power and length of extraction time on the extraction of gastrodine were examined and analysed.On the basis of this and according to the Box-Benhnken design of experiment,the method of response su-rface analysis with 3 factors and 3 levels was adopted to optimize the process parameters of gastrodin extraction.Results:(1) the optimum processes of extraction gastrodine from Rhizoma gastrodiae by ultrasonic:The study showed that the optimal value of ultrasonic power, time for ultrasonic extraction, material/liquid ratio and temperature by one-factor tests of ultrasonic extraction were 350 W,30 min,1:35,50℃. Results of RSM showed that the optimal processing conditions of ultrasonic extraction were material-liquid ratio of 1:35 (g/mL), extraction temperature of 51℃and extraction time of 33 min. The yields of gastrodin were up to 1.225% under the optimal ultrasonic extraction conditions, which was consistent with the predicted results. (2) The optimum processes of extraction gastrodine from Rhizoma gastrodiae by microwave: The study showed that the optimal value of time for microwave extraction, microwave power, temperature and material/liquid ratio by one-factor tests of microwave extraction were 3 min,400 W,50℃,1:20. Results of RSM showed the optimal processing conditions of microwave extraction were material-liquid ratio of 1:23 (g/mL), extraction time of 3 min and extraction tempreture of 55℃. The yields of gastrodin were up to 1.714% under the optimal microwave extraction conditions, which was consistent with the predicted results. Conclusion:Compared with the traditional ethanol reflux extraction,both ultrasonic extraction and microwave extraction could greatly save the extraction time,low extraction cost and achieve a good gastrodin extraction especially microwave extraction. Ultrasonic extraction and microwave extraction had a certain value on fast sample preparation and speeding up the progress of Chinese herbal medicine development.