Optimization of Acid Protease Production by Aspergillus niger I1 on Shrimp Peptone Using Statistical Experimental Design

Table 2

Plackett-Burman experimental design matrix with proteolytic enzymes production levels.

Variables	𝑇	HGW	SP	KH2PO4	MgSO4	NaCl	pH	ZnCl2	Na2HPO4	CaCl2	IS	Protease activity
Run	Units
	°C	g/L	g/L	g/L	g/L	g/L	—	g/L	g/L	g/L	Sp/mL	U/mL
(1)	30	5	5	1	0.5	0.3	8	0.1	1.6	0.4	10^7	74.11
(2)	30	15	2	2	0.5	0.3	5	0.2	1.6	0.8	5×10^6	60.58
(3)	25	15	5	1	1	0.3	5	0.1	1.6	0.8	10^7	68.62
(4)	30	5	5	2	0.5	0.6	5	0.1	0.8	0.8	10^7	78.82
(5)	30	15	2	2	1	0.3	8	0.1	0.8	0.4	10^7	85.49
(6)	30	15	5	1	1	0.6	5	0.2	0.8	0.4	5×10^6	14.11
(7)	25	15	5	2	0.5	0.6	8	0.1	1.6	0.4	5×10^6	183.13
(8)	25	5	5	2	1	0.3	8	0.2	0.8	0.8	5×10^6	128.43
(9)	25	5	2	2	1	0.6	5	0.2	1.6	0.4	10^7	74.11
(10)	30	5	2	1	1	0.6	8	0.1	1.6	0.8	5×10^6	52.94
(11)	25	15	2	1	0.5	0.6	8	0.2	0.8	0.8	10^7	55.29
(12)	25	5	2	1	0.5	0.3	5	0.1	0.8	0.4	5×10^6	96.86

𝑇: temperature; HGW: hulled grain of wheat; SP: shrimp peptone; IS: Inoculum’s size; Sp: spores.