ABSTRACT
In this study, total alkaloids from Hemsleya chinensis were extracted and tested for their antioxidant properties. To optimize extraction methods, a single factor experiment was conducted to determine the total alkaloid concentrations of H. chinensis using the L9 (34) orthogonal design test method and the BP neural network (BPNN), resulting in the optimum extraction conditions for total alkaloids. The optimal conditions for H. chinensis alkaloids extraction with acid water are: HCl concentration is 0.50 %, extraction temperature is 85 °C, material-liquid ratio is 1:64.5, and extraction rate of alkaloids is 0.2785 ± 0.0003 mg/mL. The alkaloid from H. chinensis exhibited antioxidant activity in a quantity-effect relationship with activity. These findings showed that the procedure to be reasonable, the alkaloid extraction efficiency to be high, and the method could be used to extract the alkaloids of H. chinensis, improving the development of natural and healthy medicinal resources for the pharmaceutical and food industries.