UNUSUAL FLAVONOIDS PRODUCED BY CALLUS OF HYPERICUM-PERFORATUM

6-C-prenyl luteolin, a new naturally occurring compound, together with luteolin 5,3'-dimethyl ether, luteolin 5-glucoside and luteolin 3'-gl ucoside were isolated from callus of Hypericum perforatum var. angusti folium. These flavonoids were completely different from those previous ly observed in in vivo plants of the same species. The total flavonoid content of callus, around 0.5--0.7 mg g(-1) dry wt, was much lower th an that found in wild growing Hypericum perforatum plants (14-70 mg g( -1) dry wt). (C) 1998 Elsevier Science Ltd. All rights reserved.