Diosgenin and phytosterols content in five callus lines of Dioscorea balcanica

Diosgenin is a steroidal compound very useful in pharmaceutical industry as a natural source of steroidal hormones. It is found in many wild Dioscorea species and also in endemic species Dioscorea balcanica. Callus lines obtained from a wild Dioscorea balcanica cultivar, differed in diosgenin, as well as, in phytosterols content. An attempt to select callus lines with high levels of diosgenin considered a few factors such as light, dark, addition of precursor in diosgenin biosynthesis (cholesterol) and of inhibitor of carotenoid biosynthesis (norflurazon). Light/dark conditions affected the amount of diosgenin in callus lines while quantitative differences in phytosterols' amount were less pronounced. Moreover, there are qualitative differences in their amount between callus grown on light and in the dark. The addition of cholesterol and norflurazon in cultivation medium increased the amount of both diosgenin and phytosterols. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.