RESUMO
Objective:To optimize the ultrasonic extraction process of total alkaloids from Oxytropis falcata bunge. Methods:The independent variables were solvents ratio, extracting time and ethanol concentration, and the dependent variable was content of total al-kaloids. Based on single factor tests, central composite design and response surface methodology was adopted to optimize the extraction technology. Results:The optimal extraction conditions were as follows: extracted twice with 36-fold amount of 72% ethanol ( contai-ning 1% acetic acid) at 60 ℃, and extracted 77 minutes each time. Under the above conditions, the content of total alkaloids was 2. 793 mg·g-1 with the bias ratio less than 2% when compared with the model predictions. Conclusion:Ultrasonic extraction process of total alkaloids from Oxytropis falcata Bunge optimized by central composite design and response surface method is simple, highly pre-cise, reliable and predictable.