. 2017 Jun 14;11:54. doi: 10.1186/s13065-017-0285-1

Table 3.

Quadratic polynomial equations for the three responses in terms of coded factors

Responses	Equations
Extraction yield	$Y = 20.33 - 0.95 A - 1.08 B - 0.35 C - 3.33 A B - 1.68 A C - 0.80 B C + 0.082 A^{2} - 1.36 B^{2} + 0.75 C^{2}$	(3)
DPPH radical scavenging activity	$Y = 74.41 - 8.49 A - 5.43 B - 1.52 C - 5.32 A B - 1.72 A C - 3.08 B C - 5.01 A^{2} - 1.17 B^{2} - 0.80 C^{2}$	(4)
TPC	$Y = 118.39 - 4.24 A + 0.84 B - 1.30 C - 4.69 A B - 2.17 A C + 6.11 B C - 5.13 A^{2} - 0.0027 B^{2} - 0.46 C^{2}$	(5)

In these equations, Y is the predicted response, A, B and C are the values of the independent variables, extraction temperature (°C), extraction time (min) and solvent ratio (water: ethanol) (v/v%), respectively