Objective: To study the optimum extracting process of solamargine from Solanum nigrum Method: The optimum extraction process was investigated by L9(34) orthogonal design with the yield of solamargine as index

and four factors were chosen

including ethanol concentration

solid-liquid ratio

extraction times and extraction time. HPLC was used to determine the content of solamargine. Result: The optimum extraction conditions was to reflux the herbs for two times

four hours each time with 20 times amount of 80% ethanol. Conclusion: The selected technology is reasonable and feasible

and was suitable for extraction of solamargine.