Table 2.

Central composite design matrix with coded and uncoded variables

Run	A	B	C	pH	NaHCO3 (g/l)	Inoculum size (%)
1	−1	−1	−1	4.0	3.33	10
2	1	−1	−1	8.0	3.33	10
3	−1	1	−1	4.0	10	10
4	1	1	−1	8.0	10	10
5	−1	−1	1	4.0	3.33	30
6	1	−1	1	8.0	3.33	30
7	−1	1	1	4.0	10	30
8	1	1	1	8.0	10	30
9	−1.68179	0	0	2.6	6.66	20
10	1.68179	0	0	9.4	6.66	20
11	0	−1.68179	0	6.0	1.06	20
12	0	1.68179	0	6.0	12.27	20
13	0	0	−1.68179	6.0	6.66	3.18
14	0	0	1.68179	6.0	6.66	36.81
15	0	0	0	6.0	6.66	20
16	0	0	0	6.0	6.66	20
17	0	0	0	6.0	6.66	20
18	0	0	0	6.0	6.66	20
19	0	0	0	6.0	6.66	20
20	0	0	0	6.0	6.66	20