Production, Purification, and Characterization of Thermostable α-Amylase Produced by Bacillus licheniformis Isolate AI20

Table 1

The levels of variables chosen for the Box-Behnken optimization experiment.

Variables	Variable code	−1	0	+1
Starch	𝑋1 (g/L)	5.0	7.5	10.0
Yeast extract	𝑋2 (g/L)	7.5	10.0	12.5
CaCl2	𝑋3 (g/L)	0.1	0.15	0.2