Production of 11α-hydroxyprogesterone using Aspergillus terreus immobilized on polytetrafluoroethylene

In attempt to immobilize the mycelial fungi on a new hydrophobic matrix, Aspergillus terreus mycelia were immobilized into polytetrafluoroethylen (PTFE) and used for selected conversion of progesterone to 11 alpha-hydroxyprogesterone. The immobilized cells exhibited higher yields than the free cells. Different parameters that can affect the cell activity were measured. The optimum pH was 6 and the optimum temperature was 30 degrees C. Higher transformation activities were achieved with matrix contained 40% PTFE. No considerable loss in yield was observed with storage of the cells at 4 degrees C for 30 days. Utilization of the immobilized cells in repeated batch processes indicated that the cells retained about 84% of their activity after reuse for eight successive cycles.