Spraydrying of yeast-lytic enzymes from Arthrobacter sp.

Spray drying processes are widely used for large scale preservation of biological materials e.g milk, whey, yeast, egg white, etc. Nevertheless, there is an increasing tendency for drying of catalytic active proteins. The paper presents results from experiments which were carried out to test the applicability of spray drying for the preservation of several bacterial enzymes used for the lysis of yeast cell-walls (β-1,3-glucanase, α-mannanase, chitinase and amylase) and formed by an Arthrobacter species. Enzyme solutions were obtained by concentrating the cell free cultivation liquid by cross-flow ultrafiltration. Due to the low protein content of the liquid preparation, several substances were added as stabilizers or carriers (eg. sucrose, KCl, MgSO4) and the effect was studied in further experiments. Spray drying was carried out at inlet air temperatures of 110 – 120°C and outlet air temperatures of 65 – 72°C. Best results were obtained by the addition of 10% KCl, the preparation having a crystalline consistency and a 60% yield in activity.