MECHANICAL DISRUPTION OF ARTHROBACTER SP DSM 3747 IN STIRRED BALL MILLS FOR THE RELEASE OF HYDANTOIN-CLEAVING ENZYMES

The release of three intracellular enzymes from Arthrobacter sp. DSM 3747 has been investigated. Previous experiments showed that the yield of enzyme activity could be maximized by mechanical cell disintegration in a stirred ball mill. In this paper experiments for a further biochemical engineering optimization of the disintegration step are presented. The influences of operational parameters of the stirred ball mill on the disintegration result have been detected. It could be shown that the disintegration of the investigated organism is a function of specific energy input for high cell concentrations in the suspension together with bead sizes between 0.2 and 0.8 mm. The utilization of input energy for cell rupture reaches its maximum if the disintegration rate correlates with specific energy. This result is the basis for scale-up. In those cases where the disintegration rate does not correlate with energy input due to low concentrations or large bead diameters the influence of the nondimensional mixing time or stress frequency on cell rupture has been experimentally proved.