Table 1.

Factors and experimental domain for the screening with Placket–Burrman design.

Label	Parameter	Low level (−1)	High level (+1)
A	Glucose (g/L)	12	20
B	Yeast extract (g/L)	16	32
C	Peptone (g/L)	8	24
D	KH2PO4 (g/L)	4	12
E	Inoculum size (%)	6	14
F	Medium volume (mL)	40	60
G	Initial pH	5	7
H	–	−1	1
J	–	−1	1
K	–	−1	1
L	–	−1	1