Extraction condition optimization and comparison of L-shikonin content among different Lithospermums

L-shikonin content with ethanol extraction method are compared among three different Lithospermums,and the results show the plants with L-shikonin from high to low are Xinjiang Soft Lithospermum,Dian Lithospermum and Hard Lithospermum respectively.Both the single factor experiment and L9(34) orthogonal design were used to determine the optimum extraction conditions: ethanol concentration 85%,temperature 65 ℃,time 40 min.and liquid ratio 1∶8.The operation is safe,economic and applicable to the industrial production.