Studies on the Extraction Technological Conditions of Total Flavonoids in Dracocephalum heterophyllum

Objective:Flavonoids in Dracocephalum heterophyllum was investigated by spectrometric method with rutin as standard material.Methods: During the extracting process,four main factors including concentration of extracting solution,temperature,time and solid-liquid ratio are studied by using single factor analysis method.Results:The optimal extracting conditions are obtained by orthogonal analysis as follows:methanol concentration 70%,solid-liquid ratio 1∶40,refluxing temperature 50℃ and extracting duration 2.5hours.Total flavonoids in Dracocephalum heterophyllum was 27.4110mg/g.Conclusion:The method is simple,convenient and can be applied to extract Dracocephalum heterophyllum in large scale.