The Response Surface BBD Method was Used to Optimize the Ultrasonic-Assisted Extraction of Anthocyanins from the Fruits of Eleutherococcus brachypus and Its Storage Stability and Antioxidant Properties

Table 1

Box–Behnken design optimization yield of anthocyanins (mg/g) and variance.

No	BBD experiments						ANOVA
	X1	X2	X3	Y	Actual value	Predicted value	Source	Sum of squares	Degree of freedom		Mean square		F value		value
1	15	80	200	0.66	0.66 ± 0.06	0.66	Model	2.760	9		0.307		86.39		<0.0001
2	15	75	240	1.61	1.61 ± 0.03	1.65	X1	0.423	1		0.423		119.09		<0.0001
3	20	85	200	0.80	0.80 ± 0.01	0.77	X2	0.738	1		0.738		207.71		<0.0001
4	10	75	200	1.80	1.80 ± 0.11	1.83	X3	0.095	1		0.095		26.62		0.0013
5	10	80	160	1.40	1.40 ± 0.04	1.42	X1 X2	0.016	1		0.016		4.40		0.0742
6	15	80	200	0.66	0.66 ± 0.01	0.66	X1 X3	0.003	1		0.003		0.85		0.3869
7	15	80	200	0.64	0.64 ± 0.01	0.66	X2X3	0.002	1		0.002		0.45		0.5237
8	20	75	200	1.27	1.27 ± 0.03	1.25	X1^2	0.040	1		0.040		11.26		0.0121
9	10	80	240	1.22	1.22 ± 0.05	1.15	X2^2	0.970	1		0.970		272.99		<0.0001
10	15	80	200	0.65	0.65 ± 0.07	0.66	X3^2	0.366	1		0.366		103.11		<0.0001
11	10	85	200	1.08	1.08 ± 0.02	1.10	Residual	0.025	7		0.004
12	15	85	160	1.30	1.30 ± 0.07	1.26	Lack of fit	0.024	3		0.008		22.36		0.0058
13	15	80	200	0.69	0.69 ± 0.01	0.66	Pure error	0.001	4		0.001
14	15	75	160	1.88	1.88 ± 0.15	1.83	Cor total	2.790	16
15	15	85	240	0.95	0.95 ± 0.02	1.00	Credibility analysis of the regression equations
16	20	80	240	0.76	0.76 ± 0.06	0.74	Std.dev	Mean	C.V.%	R^2		Adjusted R^2		Predicted R^2	Adeq precision
17	20	80	160	0.83	0.83 ± 0.10	0.90	0.0596	1.07	5.57	0.9911		0.9796		0.8645	25.6725

X1, ratio of liquid-to-solid (mL/g); X2, ethanol concentration (%); X3, ultrasonic irradiation power (W). Y, yield of anthocyanins (mg/g). , extremely significant.