Bioactive benzoquinones content variability in red-berry and white-berry varieties of Ardisia crenata Sims. and assessment of cytotoxic activity.

Ardisia crenata Sims (Myrsinaceae) occurs in two varieties differing in the fruit color, the red berries being common while the white ones are rare. The roots of red-berried A. crenata are a valued TCM product which contains bioactive benzoquinones such as embelin and rapanone. In this study we compared their profiles in different organs of the plant to provide an insight in the pattern of their accumulation within the two varieties. Moreover, cytotoxic activity against human melanoma and prostate cancer cells was evaluated. Quantitative HPLC revealed that the white-berried variety differs profoundly in the content of rapanone, with its total level of 606.5 mg/100 g d.w., as compared to 16.2 mg/100 g d.w. in A. crenata 'red'. Embelin was less distributed and found in minor amounts in both varieties. This is the first report on rapanone content in various parts of Ardisia crenata and on benzoquinones in the white-berried variety.