Table 2.
Analysis of variance (ANOVA) of the regression model from the Plackett-Burman design for trace element contribution to biosurfactant formation in un-coded units
| Source | DF | Adj. SS | Adj. MS | F value | P value |
|---|---|---|---|---|---|
| Model | 5 | 428.38 | 85.677 | 43.61 | 0.000 |
| Linear | 5 | 428.38 | 85.677 | 43.61 | 0.000 |
| Bo | 1 | 16.42 | 16.417 | 8.36 | 0.012 |
| Cu | 1 | 12.45 | 12.450 | 6.34 | 0.025 |
| Fe | 1 | 20.97 | 20.972 | 10.67 | 0.006 |
| Ni | 1 | 220.85 | 220.847 | 112.41 | 0.000 |
| Zn | 1 | 157.70 | 157.697 | 80.27 | 0.000 |
| Error | 14 | 27.51 | 1.965 | ||
| Total | 19 | 455.89 |
Model Summary: S, 1.40166; R2, 93.97%; adjusted R2, 91.81%; predicted R2, 87.69%; P<0.05, 5% significance level. Bo is used loosely to indicate boron and not as a chemical symbol. DF, degrees of freedom; SS, sum of squares; MS, mean sum of squares.