Table 2 Results of central composite design for ethanol concentration
From: Catalytic hydrolysis of agar using magnetic nanoparticles: optimization and characterization
Model term | Coefficient estimate | Computed t value | p Value |
|---|---|---|---|
(a) Model coefficients, t and p value for second-order regression model for Escherichia coli K12 | |||
 Intercept (β0) | 0.001986 | 8.73 | 0.000* |
  Linear coefficients | |||
   X1 (Hydrolysate concentration %) | 0.000226 | 0.89 | 0.394 |
   X2 (Temperature ºC) | − 0.000439 | − 1.73 | 0.115 |
   X3 (Time H) | 0.000090 | 0.35 | 0.730 |
  Square coefficients | |||
   X12 (Hydrolysate concentration % x Hydrolysate concentration %) | 0.000667 | 1.60 | 0.140 |
   X22 (Temperature ºC x Temperature ºC) | 0.000667 | 1.60 | 0.140 |
   X32 (Time H x Time H) | 0.000217 | 0.52 | 0.613 |
  Interaction coefficients | |||
   X1X2 (Hydrolysate concentration % x Temperature ºC) | 0.000247 | 0.44 | 0.667 |
   X1X3 (Hydrolysate concentration % x Time H) | 0.000672 | 1.20 | 0.256 |
   X2X3 (Temperature ºC x Time H) | − 0.000389 | − 0.70 | 0.502 |
(b) Model coefficients, t and p value for second-order regression model for Saccharomyces cerevisiae S288c (ATCC 7754) | |||
 Intercept (β0) | 0.005606 | 9.93 | 0.000 * |
  Linear coefficients | |||
   X1 (Hydrolysate concentration %) | − 0.004829 | − 7.67 | 0.000 * |
   X2 (Temperature ºC) | − 0.004151 | − 6.59 | 0.000 * |
   X3 (Time H) | 0.001417 | 2.25 | 0.048 * |
  Square coefficients | |||
   X12 (Hydrolysate concentration % x Hydrolysate concentration %) | 0.00355 | 3.45 | 0.006 * |
   X22 (Temperature ºC x Temperature ºC) | 0.00180 | 1.75 | 0.111 |
   X32 (Time H x Time H) | 0.00010 | 0.10 | 0.922 |
  Interaction coefficients | |||
   X1X2 (Hydrolysate concentration % x Temperature ºC) | 0.00315 | 2.27 | 0.046 * |
   X1X3 (Hydrolysate concentration % x Time H) | − 0.00145 | − 1.05 | 0.319 |
   X2X3 (Temperature ºC x Time H) | − 0.00279 | − 2.02 | 0.071 |