Maintenance and operational stability of immobilized Arthrobacter simplex for the ▵1-dehydrogenation of steroids

Abstract The stability of the ▵ 1 -dehydrogenation system of Arthrobacter simplex immobilized in calcium alginate has been studied. A high stability was related to the ability of the cells to utilize a carbon source such as d -glucose or steroid. Inhibition of de novo protein synthesis reduced the ▵ 1 -dehydrogenase [3-oxosteroid: acceptor) ▵ 1 -oxidoreductase, EC 1.3.99.4] stability of the immobilized cells. The operational stability of immobilized cell preparations in the presence of the steroid degradation inhibitor, α,α-dipyridyl, could not be improved significantly by supplementing steroid substrate suspensions with either d -glucose or yeast extract.