Table 2.

Analysis of variance (ANOVA) and fitness of the model regression equation

Source	Yield (%)		TPC (mg GAE/g DW)		TFC (mg NAE/g DW)		DPPH (% Inhibition)
	SS	p-value	SS	p-value	SS	p-value	SS	p-value
Model	56.38	0.009**	1.91	0.001***	2.35	0.000***	382.38	0.000***
Linear	50.61	0.001**	1.69	0.000***	2.25	0.000***	324.96	0.000***
$X_1$	0.06	0.760	0.06	0.032*	0.24	0.000***	0.21	0.645
$X_2$	2.53	0.093	0.02	0.204	0.00	0.009**	24.88	0.003**
$X_3$	48.02	0.000***	1.61	0.000***	2.01	0.000***	299.87	0.000***
Quadratic	2.98	0.285	0.16	0.028*	0.07	0.000***	11.34	0.071
$X_1^2$	0.02	0.709	0.02	0.308	0.00	0.008**	2.72	0.188
$X_2^2$	1.91	0.116	0.00	0.522	0.00	0.149	8.49	0.025*
$X_3^2$	1.05	0.240	0.14	0.007**	0.07	0.000***	0.13	0.712
Interaction	2.79	0.307	0.06	0.158	0.03	0.000***	46.09	0.004**
$X_1{X}_2$	0.00	1.000	0.02	0.141	0.00	0.388	0.26	0.604
$X_1{X}_3$	2.72	0.085	0.02	0.139	0.02	0.000***	44.85	0.001***
$X_2{X}_3$	0.06	0.758	0.01	0.227	0.00	0.364	0.97	0.334
Lack of fit	1.79	0.529#	0.02	0.618#	0.00	0.320#	4.05	0.072#
R2	0.9502		0.9811		0.9996		0.9890
Adjusted R2	0.8606		0.9469		0.9989		0.9692
PRESS	31.23		0.35		0.01		65.25

SS sum of square; PRESS prediction error sum of squares; TPC total phenolic content; TFC total flavonoid content; DPPH DPPH radical scavenging activity; GAE gallic acid equivalents; NAE naringin equivalents

*p < 0.05, **p < 0.01, ***p < 0.001 indicates significance; ^#p of lack of fit indicates not significance (low standard errors)