VARIATION IN ISODIOTIGENIN AND DIOSGENIN CONTENT IN AERIAL PARTS OF DIOSCOREA TOKORO

The effect of fermentation on the yields of the steroidal sapogenins of Dioscorea tokoro Makino was examined. Although the concentration of diosgenin in newly sprouted shoots of mature plants was 0·006 per cent and the yield was increased by fermentation, the amount in tops of mature shoots and leaves was less than 0·001 per cent and was not increased by the same procedure. The amounts of yonogenin and isodiotigenin increased markedly whereas the concentration of tokorogenin decreased after fermentation. When the small parts of rhizomes lacking apical buds were planted in the field, significant amounts of isodiotigenin appeared in the aerial parts of these vegetatively propagated plants. The greater part of the diosgenin found in the rhizome is probably synthesized there. © 1969.