Table 2 Central composite design for metal ion factors associated with spore density by the fluorometric assay
Run | Models | Metal ions concentration (mM) | Fluorescence intensity (AU) | ||||
|---|---|---|---|---|---|---|---|
Mn2+ (x1) | Fe2+ (x2) | Ca2+ (x3) | Mg2+ (x4) | Experimental | Predicted | ||
1 | 0000 | 1 | 3 | 2 | 3 | 299.2 ± 44.7 | 299.1 |
2 | 0a00 | 1 | 1.52 | 2 | 3 | 292.1 ± 38.3 | 290.3 |
3 | −−++ | 0.5 | 2 | 3 | 4 | 280.8 ± 21.2 | 278.4 |
4 | +−++ | 1.5 | 2 | 3 | 4 | 284.4 ± 38.2 | 286.3 |
5 | ++++ | 1.5 | 4 | 3 | 4 | 282.3 ± 30.0 | 282.2 |
6 | −+++ | 0.5 | 4 | 3 | 4 | 268.2 ± 24.3 | 268.0 |
7 | −−−+ | 0.5 | 2 | 1 | 4 | 263.4 ± 20.2 | 265.1 |
8 | ++−− | 1.5 | 4 | 1 | 2 | 280.8 ± 28.6 | 282.0 |
9 | ++−+ | 1.5 | 4 | 1 | 4 | 281.5 ± 30.4 | 276.7 |
10 | 000A | 1 | 3 | 2 | 4.48 | 288.5 ± 27.6 | 290.4 |
11 | −−+− | 0.5 | 2 | 3 | 2 | 280.5 ± 23.3 | 284.4 |
12 | a000 | 0.26 | 3 | 2 | 3 | 278.8 ± 20.1 | 278.8 |
13 | +−−+ | 1.5 | 2 | 1 | 4 | 266.4 ± 17.4 | 265.8 |
14 | 0000 | 1 | 3 | 2 | 3 | 302.9 ± 33.1 | 299.1 |
15 | −+−− | 0.5 | 4 | 1 | 2 | 287.2 ± 25.7 | 284.4 |
16 | +−+− | 1.5 | 2 | 3 | 2 | 284.5 ± 24.0 | 283.1 |
17 | +−−− | 1.5 | 2 | 1 | 2 | 271.0 ± 18.4 | 270.4 |
18 | +++− | 1.5 | 4 | 3 | 2 | 282.2 ± 24.6 | 279.6 |
19 | 00a0 | 1 | 3 | 0.52 | 3 | 273.9 ± 23.6 | 277.6 |
20 | 0A00 | 1 | 4.48 | 2 | 3 | 285.5 ± 23.3 | 291.2 |
21 | A000 | 1.74 | 3 | 2 | 3 | 279.1 ± 26.0 | 282.9 |
22 | −−−− | 0.5 | 2 | 1 | 2 | 280.1 ± 4.7 | 279.0 |
23 | −++− | 0.5 | 4 | 3 | 2 | 275.2 ± 17.4 | 274.6 |
24 | 00A0 | 1 | 3 | 3.48 | 3 | 285.4 ± 19.5 | 285.6 |
25 | −+−+ | 0.5 | 4 | 1 | 4 | 269.6 ± 15.3 | 269.8 |
26 | 000a | 1 | 3 | 2 | 1.52 | 296.9 ± 24.5 | 298.8 |
27 | 0000 | 1 | 3 | 2 | 3 | 302.2 ± 26.6 | 299.1 |