Table 4.
The coded second-order regression coefficients for the encapsulation yield (EY) and the retentions of total saponin (TSC), total phenolic (TPC) and total flavonoid (TFC) content and the total antioxidant activity (TAA) for the bitter melon extract encapsulated powder obtained from the RSM CCD design.
| Independent Variables | Regression Coefficient Values | ||||
|---|---|---|---|---|---|
| EY (Y1) | TSC (Y2) | TPC(Y3) | TFC (Y4) | TAA (Y5) | |
| Intercept | 63.97 | 61.58 | 56.51 | 50.39 | 44.33 |
| Linear | |||||
| X1 | 5.10 * | 5.04 * | 9.24 ** | 14.66 *** | 6.84 * |
| X2 | −6.53 * | 4.82 * | −1.07 | −0.82 | 0.70 |
| Quadratic | |||||
| X1 X1 | 0.87 | 4.94 | 12.51 ** | 9.53 * | 14.01 ** |
| X2 X2 | −1.63 | 4.53 * | 16.67 ** | 6.81 * | 22.48 *** |
| Interaction | |||||
| X1X2 | 4.46 | −1.45 | −1.51 | 0.13 | −2.69 |
| R2 | 0.86 | 0.87 | 0.98 | 0.97 | 0.98 |
| p-value of lack of fit | 0.083 | 0.062 | 0.071 | 0.100 | 0.075 |
X1: The overall concentration of the encapsulation agents’ stock solution; X2: The ratio of the bitter melon extract to the encapsulation agents’ stock solution; *: p < 0.05; **: p < 0.01; ***: p < 0.0001.