Analysis of the Inactivation Kinetics of Freeze-dried α-Amylase fromBacillus amyloliquefaciensat Different Moisture Contents

Abstract

The thermal inactivation kinetics of freeze-dried α-amylase in a solid matrix was studied at water contents ranging from 1.5

Thermal Inactivation Kinetics of Suspensions of α-Amylase in Hydrophobic Organic Solvents

“…Preliminary experiments indicating linearity between enzyme concentration and initial activity (∆OD/min), the stability of amylase during lyophilization and equilibration above the saturated salt solutions were previously reported (12). A similar method was used in this work.…”

“…A thorough description of the model equations, regression procedures and statistical interpretation of the results is provided in a previous work (12). Using the Bigelow model, the remaining activity of an enzyme inactivating according to a first order decay at constant temperature T, is given by:…”

“…In the present case of α-amylase the initial drop occurs very fast and is too small to allow for its measurement at the temperatures studied and therefore it is difficult to propose a two-fraction model with the data available. (12). This suggests that the inactivation mechanism was not changed by the introduction of the organic solvents.…”

“…The characteristics of the α-amylase used in this work (from B. amyloliquefaciens, later referred to as α-amylase), the lyophilization and thermal treatment conditions, the equilibration procedure above saturated salt solutions to obtain the desired water content and the activity analysis procedure are described in another work (12). The enzyme used was from a different lot to the enzyme used in the work cited.…”

“…29 (1996) found (12). For mathematical interpretation of the results, it is possible to simply discard the initial value.…”