Parameters Pre-planned contrasts df P value
Linea 0 vs. 0.3 mg/mL 3 <0.0001
  0 vs. 0.6 mg/mL 3 <0.0001
  0 vs. 1.2 mg/mL 3 <0.0001
  0.6 vs. 1.2 mg/mL 3 <0.0001
β1b 0 vs. 0.3 mg/mL 1 0.8702
  0 vs. 0.6 mg/mL 1 0.3813
  0 vs. 1.2 mg/mL 1 0.0004
  0.6 vs. 1.2 mg/mL 1 0.0197
β2c 0 vs. 0.3 mg/mL 1 0.28
  0 vs. 0.6 mg/mL 1 0.48
  0 vs. 1.2 mg/mL 1 0.10
  0.6 vs. 1.2 mg/mL 1 0.05
aLine represents the estimated line of growth over time, bβ1 represents the rate at which bacterial growth over time, and cβ2 represents the point of inflection where growth reached its maximum at a specific time. The parameter estimates for 2.4 mg/mL PGF treatment were non-significant (P>0.05; Table 1)
Table 2: Degrees of freedom (df), and associated P–values for the pre-planned contrasts of estimated parameters for growth of S. aureus treated with various concentrations of PGF using Model: (Y = β0 + β1 x +β2 x2 + ε1).