Xanthone production in calli and suspended cells of Hypericum perforatum

Calli and suspended cells of Hypericum perforatum accumulated xanthones wit h the 1,3,6,7 and 1,3,5,6-oxygenation pattern. Xanthone accumulation was hi ghly influenced by hormone supplementation. Calli grown with 4.5 mu mol/L 2 ,4-D + 2.3 mu mol/L KIN had the highest specific xanthone production observ ed (0.73% DW). The use of BA instead of KIN reduced xanthone accumulation, resulting in the lowest production achieved (0.24 % DW). This effect was at tenuated when both hormones were present. Calli displayed a positive linear relationship between NAA concentration, in the range of 4.5-22.5 mu mol/L, and total xanthone accumulation and the xanthone 1,3,6,7/1,3,5,6 ratio. Ho wever, the production of 1,3,5,6 xanthones was similar in ail NAA concentra tions studied.