Table 2: ANOVA for surface response quadratic polynomial model for citric acid production.
Factor |
Sum of squares (SS) |
Degree of Freedom |
Mean square |
F-value |
P-value |
Interpretation |
A |
5.50 |
1 |
5.50 |
5.68 |
0.0545 |
Significant |
A2
|
4.02 |
1 |
4.02 |
4.15 |
0.0877 |
Marginally significant |
B |
11.13 |
1 |
11.14 |
11.49 |
0.0147 |
Significant |
B2
|
1.14 |
1 |
1.17 |
1.18 |
0.3196 |
– |
C |
6.47 |
1 |
6.47 |
6.68 |
0.0414 |
Significant |
C2
|
2.26 |
1 |
2.26 |
2.33 |
0.1772 |
– |
D |
8.27 |
1 |
8.27 |
8.53 |
0.0266 |
Significant |
D2
|
0.39 |
1 |
0.39 |
0.40 |
0.5488 |
– |
E |
0.07 |
1 |
0.07 |
0.07 |
0.8013 |
– |
E2
|
4.17 |
1 |
4.17 |
4.30 |
0.0833 |
Marginally significant |
AB |
0.49 |
1 |
0.49 |
0.51 |
0.5031 |
– |
AC |
4.36 |
1 |
4.37 |
4.51 |
0.0779 |
Marginally significant |
AD |
0.39 |
1 |
0.39 |
0.41 |
0.5444 |
– |
AE |
2.13 |
1 |
2.14 |
2.21 |
0.1878 |
– |
BC |
2.03 |
1 |
2.03 |
2.09 |
0.1974 |
– |
BD |
3.69 |
1 |
3.69 |
3.82 |
0.0986 |
Marginally significant |
BE |
2.08 |
1 |
2.08 |
2.15 |
0.1929 |
– |
CD |
0.65 |
1 |
0.65 |
0.68 |
0.4410 |
– |
CE |
0.59 |
1 |
0.59 |
0.61 |
0.4629 |
– |
DE |
0.17 |
1 |
0.17 |
0.17 |
0.6864 |
– |
Error |
5.8139 |
6 |
0.9690 |
– |
– |
– |
Total SS |
53.0265 |
26 |
– |
– |
– |
– |