Abstract：The effects of ultrasonic wave power and treatment time on the cell growth and shikonin biosynthesis of Arnebia euchroma were investigated. The results showed that the stimulation of ultrasonic wave promoted A. euchroma cell growth in suspension culture. Low power density and long time treatment or high power density and short time treatment by ultrasonic wave was favorable to the cell growth. The cell biomass productivity was 61% higher than that in control by the end of the culture period under the optimal conditions of 200 W ultrasonic wave treatment for 1 min. The shikonin content and shikonin production in suspension culture of A. euchroma cells were enhanced by ultrasonic stimulation as well. When the ultrasonic stimulation was carried out after inoculation, the ultrasonic power density was 39.9 mW/cm3 and the stimulation time was 3 min, the shikonin content and shikonin production gained the highest results (2.72%, 294 mg/L), which were 64% and 135% higher than those obtained in control, respectively. The strengthening of shikonin biosynthesis may be due to increasing the activity of phenylalanine ammonia lyase caused by ultrasonic stimulation.
2008, Vol. 8 
