Table 4.

Regression model formula for predicting independent variables and responses from the experimental model.

Responses	Regression model formula (y)	Linearity (R2)
Trans-cinnamaldehyde contenta	y = 1041.86-63.61$x_1$-503.83$x_2$-70.82$x_3$-8.42$x_1{x}_2$-102.97$x_1{x}_3$ + 3.03$x_2{x}_3$+187.98$x_1^2$ + 32.06$x_2^2$–85.48$x_3^2$	0.9812
Coumarin contenta	y = 1152.79 + 8.42$x_1$-499.42$x_2$-59.18$x_3$ + 12.52$x_1{x}_2$–136.66$x_1{x}_3$ + 103.77$x_2{x}_3$+5.77$x_1^2$ + 40.17$x_2^2$–120.51$x_3^2$	0.9737
Brazilin contentb	y = 185.35-19.42$x_1$-75.05$x_2$ + 60.29$x_3$+7.82$x_1{x}_2$-8.97$x_1{x}_3$-30.62$x_2{x}_3$	0.9848

The yields of bioactive substances (responses) were represented as y, whereas x₁, x_2, and x₃ represent factors A (percentage of glycerol [hydrogen bond donor] in NADES), B (percentage of natural deep eutectic solvent [NADES] without sample powder), and C (percentage of water in NADES), respectively. The analysis was performed via analysis of variance for the ^aquadratic and ^btwo-factor interactions models.