Table 1.

D-optimal design showing the experimental runs carried out and the observed and predicted responses

Run Order	pH (A)	Temperature (B, °C)	Inoculum size (C, % v/w)	IZ diameter (mm)
				Observed response	Predicted response
1	8.50	37.00	5.00	20	19.79
2	8.50	23.00	5.00	21	20.82
3	5.50	37.00	5.00	0	0.04
4	8.50	37.00	35.00	21	20
5	8.50	23.00	35.00	18	18.35
6	6.25	30.00	12.50	23	21.26
7	5.50	37.00	35.00	0	0.2
8	8.50	37.00	5.00	19	19.79
9	7.00	30.00	20.00	24	23.83
10	5.50	23.00	20.00	21	20.52
11	7.00	30.00	35.00	22	23.27
12	5.50	23.00	5.00	21	21.75
13	8.50	23.00	35.00	19	18.35
14	5.50	37.00	35.00	0	0.21
15	7.00	23.00	5.00	23	23.2
16	8.50	30.00	20.00	26	26.64