XVI International Botanical Congess

The effects of some physical and chemical factors on callus growth and flavonoids formation in callus cultures of S. medusa, which is traditional Chinese medicine, were studied. According to our experiments, the optimal temperature for callus growth and flavonoids formation was 25?C. Authors also found that flavonoids formation were strongly inhibited under dark condition, and stimulated by white light. Callus growth was promoted when 1 mg/L NAA and 0.2 mg/L KT were added to the media. The combination of 3% sucrose and 1% glucose was useful for callus growth and flavonoids formation. A fine callus strain of S. medusa was selected through irradiation with 4000 Gy of y-ray. The growth rate and flavonoids content of the callus strain were high and stable. Sensitive and rapid methods of high-performance liquid chromatography as well as UV spectrophotometry were developed for detecting the flavonoids in cultured cells. The results revealed that the content of total flavonoids in dry cells under white light and 25?C condition was 6.2%, which was 4.4 times as that under dark condition, and which was 5 and 3.2 times as those cultured at 20?C and 35?C respectively.