IMMOBILIZATION OF BACILLUS-ACIDOCALDARIUS WHOLE-CELL RHODANESE IN POLYSACCHARIDE AND INSOLUBILIZED GELATIN GELS

The presence of rhodanese activity has been investigated in two strain s of thermophilic eubacteria and two strains of extremophiles, Bacillu s acidocaldarius, a thermoacidophilic eubacterium, showed the highest levels of enzyme activity. Whole cells, previously subjected to one cy cle of freeze-thawing, were immobilized by entrapment in the polysacch aride matrices Ca-alginate, kappa-carrageenan and chitosan, and in an insolubilized gelatin gel, The results obtained with the different imm obilizates in terms of activity yield, possibility of regeneration and operative stability were evaluated with the aim of setting up a conti nuous system, This was achieved with a system consisting of B, acidoca ldarius cells entrapped in an insolubilized gelatin matrix, The latter , in the form of a thin membrane, was employed in a custom-conceived r eactor operating as a plug flow reactor.