Immobilized cells of the saprophytic Claviceps fusiformis culture can be cultivated under semicontinuous conditions for long time periods. The biocatalyst can produce alkaloids for up to 550 days with 25 cycles of the medium replacement. Specific productivity of the catalyst (average during first 100 days) is 6200 μg of alkaloids per g wet mass of the mycelium per day. Glycolytic pathway in the immobilized cells exhibited 100 times higher catabolic activity (phosphofructokinase) than gluconeogenetic activity (fructose 1,6-bisphosphatase). In immobilized cells, the final production phase was characterized by a decrease in activity of the tricarboxylic acid cycle (malate dehydrogenase and citrate synthase), similarly to suspension culture. It has been proved that during 50 days of semicontinuous cultivation the immobilized cells maintain sufficient activity of the key catabolic pathways and consequently a physiological state suitable for the production of clavine alkaloids. Morphological and ultrastructural changes were studied with scanning and transmission electron microscopy.
Křen V., Kozová J., Ludvík J., Kofroňová O., Řeháček Z. (1988): Physiological activity of immobilized Claviceps cells producing clavine alkaloids. – Česká Mykologie 42(1): 52–55.
