2.4. Medium optimization
An OFAT method was used to determine the main factors affecting growth and antifungal activity.
An orthogonal design (L9[33]) was applied to evaluate the effects of the following factors: soluble starch (A), yeast extract (B) and CaCl2 (C).
Nine experiments were performed to evaluate the best conditions for antifungal activity
of BT4. Factors and test levels are in Table 1. Data were analyzed using SPSS
statistical software (SPSS for windows, version 18.0; SPSS Inc.).