Table 1.

High (+) and low (-) values in Plackett Burman Design for screening independent variables in act-D production.

Factor	Variables	Factors levels of (gL−1)
		-1	+1
Starch	X1	5	15
KCl	X2	0,3	0.7
NaNO3	X3	1	5
K2HPO4	X4	0.6	1.4
MgSO4, 7H2O	X5	0.3	0.7
pH	X6	5.2	9.2