Application of immobilized cells for biotransformations of steroids

A survey is given of possible solutions and open-ended questions in the biotransformation of steroids (without side chain degradation of sterols) by using immobilized cells. The data of literature between 1975 and 1990 and results of preliminary experiments from the microbial, biochemical, biophysical, physiological, as well as the biotechnological point of view are summarized and discussed.