Optimisation of ultrasonic-assisted extraction and biological activity of total flavonoids from leaves of Murrayae exotica using response surface methodology

Figures & Tables

Elution profile of MELPTF on AB-8 macroporous resin column. MELPTF, MELTF after purification.

Source	Sum of squares	Df	Mean square	F-value	p-value	Significant^a
Model	20.16	9	2.24	10.82	0.0024
X₁	6.88	1	6.88	33.24	0.0007
X₂	2.97	1	2.97	14.36	0.0068	**
X₃	3.13	1	3.13	15.11	0.0060	***
X₁X₂	0.26	1	0.26	1.26	0.2987	**
X₁X₃	0.72	1	0.72	3.49	0.1038	**
X₂X₃	0.15	1	0.15	0.71	0.4273	*
X₁²	2.53	1	2.53	12.23	0.0100	*
X₂²	1.77	1	1.77	8.53	0.0223
X₃²	1.14	1	1.14	5.49	0.0516
Residual	1.45	7	0.21
Lack of fit	0.79	3	0.26	1.58	0.3255	Not significant
Pure Error	0.66
Cor total	21.61	4
R²	0.9329	16
R_2adj.	0.8467

Run	X₁	X₂	X₃	Extraction yield (mg · g⁻¹)
Run	X₁	X₂	X₃	Experimental	Predicted
1	−1	−1	0	5.71	5.29
2	0	1	1	8.33	8.26
3	0	0	0	7.42	8.00
4	0	1	−1	6.85	6.62
5	0	−1	−1	5.71	5.79
6	1	−1	0	6.53	6.64
7	0	0	0	7.74	8.00
8	0	0	0	8.30	8.00
9	1	0	−1	7.62	7.43
10	−1	0	−1	4.39	4.73
11	0	0	0	8.38	8.00
12	0	−1	1	6.43	6.65
13	−1	0	1	6.63	6.83
14	−1	1	0	6.11	6.00
15	1	1	0	7.95	8.37
16	1	0	1	8.17	7.83
17	0	0	0	8.14	8.00

No.	Optimum conditions			Extraction yield (mg · g⁻¹)
No.	Solvent concentration (%)	Ultrasonic time (min)	Liquid-solid radio (mL · g⁻¹)	Experimental	Predicted
1	76	55	22	8.79	8.62
2	76	55	22	8.28	8.62
3	76	55	22	8.39	8.62
4	76	55	22	8.56	8.62
5	76	55	22	8.93	8.62
Average				8.59
Ethanol leaching extraction
6	0	20	20	3.38
7	0	20	20	3.28
8	0	20	20	3.42
Average				3.36

Code	Solvent concentration (%)	Ultrasonic time (min)	Liquid-solid ratio (mL · g^-1)
−1	60	30	15
0	70	45	20
1	80	60	25