70 ml of buffer was pipetted into each
Erlenmeyer flask with weighed substrate. For preventing microbial
contamination during the hydrolysis, Erlenmeyer flasks were
sealed with a stoppers, the content was boiled for 10 min in water
bath and, after cooling, the suspension was supplemented with
preservative agent – sodium azide (at a concentration of 0.02%
w/v of azide).