Abstract: Objective To optimize the extraction process of Scutellariabar bata total alkaloids with central- composite- design response- surface method. Methods Five main factors including ethanol volume fraction，extraction time，solid-liquid ratio，extraction temperature，and extraction times on this reflux extraction process were investigated，to screen the influence of various factors on the yield of S. barbata total alkaloid extraction with ultraviolet spectrophotometry. Central composite design was used to design experiments，and SAS was used to establish a prediction model，and response surface method was used to abtain the best extraction process. Results The optimal process conditions were 40. 06 times of 55. 20%ethanol reflux extraction under 85 ℃ for two times，each 113. 29 min. Under the optimal process conditions，the total alkaloid content was 26. 932 9 mg/g，and the deviation of predicted values and measured values were less than 2%. The binomial fitting correlation coefficient was R² =0. 997 5. Conclusion Central-composite-design response-surface methods is successfully used for the optimization on theextraction process of S. barbatatotal alkaloids，with good predictability and stability.

Key words: Scutellariabarbata, total alkaloids, extraction process, central composite design, response surface method