Table 3.

Box–Behnken experimental design and experimental vs predicted xylanase activity values for various combination of fermentation conditions

Run no.	Ba,d (mL/100 mL)	Kb,d (mL/100 mL)	Solid (%w/v)	pH	Activity (IU/mL)
					Experimentalc	Predicted
1	2.50	4.00	25.0	7.0	17.01 ± 0.86	18.93
2	4.00	2.50	10.0	5.5	7.96 ± 0.43	8.84
3	1.00	1.00	25.0	5.5	21.75 ± 0.86	20.12
4	2.50	2.50	25.0	5.5	17.44 ± 0.86	17.83
5	4.00	2.50	25.0	7.0	24.12 ± 0.65	22.89
6	2.50	2.50	10.0	7.0	5.52 ± 0.28	2.84
7	2.50	2.50	10.0	4.0	3.65 ± 0.43	0.44
8	2.50	1.00	10.0	5.5	4.51 ± 0.43	7.52
9	2.50	1.00	25.0	4.0	9.25 ± 0.86	8.31
10	2.50	2.50	40.0	4.0	20.46 ± 0.86	21.72
11	4.00	2.50	40.0	5.5	40.49 ± 0.65	40.38
12	2.50	2.50	25.0	5.5	18.52 ± 0.65	17.83
13	1.00	4.00	25.0	5.5	17.01 ± 0.43	14.09
14	2.50	1.00	25.0	7.0	22.18 ± 0.43	20.87
15	1.00	2.50	25.0	7.0	13.56 ± 0.43	15.24
16	4.00	1.00	25.0	5.5	18.30 ± 0.43	19.80
17	2.50	2.50	40.0	7.0	42.65 ± 0.65	44.43
18	2.50	4.00	40.0	5.5	39.42 ± 0.43	37.01
19	2.50	2.50	25.0	5.5	17.44 ± 0.86	17.83
20	2.50	1.00	40.0	5.5	42.00 ± 0.86	41.54
21	1.00	2.50	25.0	4.0	4.73 ± 0.17	6.56
22	4.00	2.50	25.0	4.0	7.53 ± 0.43	6.45
23	2.50	4.00	10.0	5.5	7.10 ± 0.43	8.17
24	2.50	4.00	25.0	4.0	4.08 ± 0.43	6.37
25	1.00	2.50	40.0	5.5	36.40 ± 0.43	36.50
26	1.00	2.50	10.0	5.5	4.08 ± 0.43	5.18
27	4.00	4.00	25.0	5.5	21.75 ± 0.86	21.95

^a B. subtilis

^b K. marxianus

^cResults are averages of three replicates

^dGrowth medium contains 6 × 10⁷ cfu/mL