Solvay Protease

In the course of our development work it turned out that Optimase M 440 was no longer available [39]. Since it was known from another project that the liquid enzyme formulations exhibit a less pronounced emulsifying behavior (cf. [37]), the different commercial bulk preparations, now Alcalases and Solvay Proteases, were re-evaluated. All yielded very good results with respect to chemical purity and enantiomeric excess (>99% each). However, Solvay Protease L 660 (the successor of Optimase L 660) was clearly the most active enzyme, thus requiring the smallest amount of enzyme for the reaction. The clearly higher price of this enzyme [40] should be of no consequence because of the expected simpler work-up and, hence, lower manpower costs. 

After some orientating experiments employing the newly selected liquid enzyme preparation a simple extraction procedure comprising three extractions at pH 8.5 and two at pH 2 could be developed. On comparison of the solid enzyme preparation Optimase M 440 with Solvay Protease L 660, it turned out that the removal of... 

As Subtilisin Carlsberg was, and still is, one of the cheapest enzymes available on the market, no further proteases were tested. Four Subtilisin Carlsberg preparations from Solvay Enzymes [9] and Novo Nordisk [10] were tested successfully Solvay-Protease M 440 (solid form) and L 660 (liquid form) as well as the Novo enzymes Alcalase 2.0 T (solid) and Alcalase 2.5 L (liquid). 

Owing to experience previously gained concerning work-up with the solid enzyme formulations [22] only the liquid enzyme preparations of Novo and Solvay, Alkalase 2.5 L and Protease L 660, respectively, were used in the following studies. Both preparations exhibited nearly the same specific activity in the present reaction. An enzyme concentration of <5% (v/w) with respect to 9 (s/e> 20 [24]) was used in the subsequent experiments of this section. 

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