Optimization of Synthesis of Seleno-Sargassum fusiforme (Harv.) Setch. Polysaccharide by Response Surface Methodology, Its Characterization, and Antioxidant Activity

Table 3

Analysis of variance of regression model.

Parameter	Sum of squares	Df	Mean square	Standard error	𝐹 value	𝑃 value
Intercept	—	1	—	0.021	—	—
𝑋1	0.12	1	0.12	0.017	52.82	0.0002**
𝑋2	0.30	1	0.30	0.017	136.66	<0.0001**
𝑋3	0.077	1	0.077	0.017	35.19	0.0006**
𝑋1𝑋2	0.093	1	0.093	0.023	42.25	0.0003**
𝑋1𝑋3	0.010	1	0.010	0.023	4.74	0.0659
𝑋2𝑋3	0.036	1	0.036	0.023	16.45	0.0048**
𝑋1^2	0.32	1	0.32	0.023	147.66	<0.0001**
𝑋2^2	0.58	1	0.58	0.023	266.10	<0.0001**
𝑋3^2	7.668𝐸−003	1	7.668𝐸−003	0.023	3.49	0.1038
Model	1.62	9	0.18	—	81.77	<0.0001**
Residual	0.015	7	2.195𝐸−003	—
Lack of fit	0.012	3	4.001𝐸−003	—	4.76	0.0829
Pure error	3.361𝐸−003	4	8.403𝐸−004
Cor total	1.63	16

𝑅² = 0.9906, adjusted 𝑅² = 0.9785, C.V. = 0.0162, ^∗𝑃<0.05, ^∗∗𝑃<0.01.