EFFECTS OF PRECURSORS ON SERIALLY PROPAGATED DIGITALIS-LANATA LEAF AND ROOT CULTURES

Serially propagated Digitalis lanata leaf and root cultures established from germinated seeds were studied for digoxin production. Leaf cultures were grown and maintained in a medium containing benzyl adenine, and root cultures in the same medium with indoleacetic acid. A consistently high digoxin content, as determined by radio-immunoassay, is present in the leaf culture (9.0 mg % dry wt) and in root culture (1.9 mg % dry wt) as compared to unorganized cells (0.06 mg % dry wt). Leaf liquid cultures grew very rapidly as compared to the root cultures and the unorganized cell suspension cultures. The concentration of digoxin increased in both leaf and root cultures by adding to the medium either sodium glycocholate, cholesteryl acetate, or progesterone. Smilageninacetate increased the digoxin content of root cultures but not that of leaf cultures. Lanosterol and 5β-androstan-3,17-dione did not significantly increase the concentration of digoxin. Deoxycholic acid was toxic to the tissues studied. © 1979.