Common chemicals and solvents of analytical grade were obtained
from different commercial sources. Alcalase 2.4 L serineprotease
from Bacillus licheniformis was supplied by Novozymes
(Bagsvaerd, Denmark). Sephadex G-25 was purchased from Pharmacia
(Uppsala, Sweden). Water was obtained from a Culligan
system; the resistivity was approximately 18 MU. All other chemicals
and reagents used were of analytical grade.