Table 3.

Determination of brazilin content in Caesalpinia sappan natural deep eutectic solvent (NADES) extracts using different experimental designs.

Run	Independent Variables					Response R1: Brazilin levels (μg/ml)
	(x1) Ratio of glycerol vs ChCl in NADES (%)		(x2) Ratio of NADES vs sample powders (%)		(x3) Percentage of water added (%)
	Glycerol	ChCl	NADES	Powder		Predicted	Actual
1	49.50	50.50	80.00	20.00	10.00	80.62	74.21 ± 0.19b
2	49.50	50.50	80.00	20.00	50.00	139.97	141.39 ± 1.27
3	49.50	50.50	66.00	34.00	10.00	169.49	179.02 ± 0.71
4	33.00	67.00	80.00	20.00	30.00	121.89	132.66 ± 1.98
5	49.50	50.50	73.33	26.67	30.00	185.35	174.04 ± 0.87
6	49.50	50.50	73.33	26.67	30.00	185.35	177.74 ± 0.47
7	33.00	67.00	73.33	26.67	50.00	274.02	268.94 ± 0.78
8	66.00	34.00	66.00	34.00	30.00	233.17	233.25 ± 1.92
9	66.00	34.00	73.33	26.67	10.00	114.61	112.11 ± 0.27
10	66.00	34.00	73.33	26.67	50.00	217.25	206.91 ± 15.48
11	33.00	67.00	66.00	34.00	30.00	287.63	282.45 ± 2.10
12	49.50	50.50	66.00	34.00	50.00	351.31	368.67 ± 1.66a
13	66.00	34.00	80.00	20.00	30.00	98.69	114.72 ± 2.54
14	49.50	50.50	73.33	26.67	30.00	185.35	175.84 ± 1.06
15	33.00	67.00	73.33	26.67	10.00	135.50	138.26 ± 1.26

Bioactive contents are expressed as the mean ± SEM of two replicates. The extraction conditions that produced the (a) highest and (b) lowest bioactive compound yields are labeled.