Table 2.

Regression coefficients of the predicted second-order model for the response variables

Model parameter	Particle size (Y1) (R2 = 0.9369)		Zeta potential (Y2) (R2 = 0.9840)		Polydispersity (Y3) (R2 = 0.9623)		Derived count rate (Y4) (R2 = 0.8916)
	Coefficient	S.E.1	Coefficient	S.E.	Coefficient	S.E.	Coefficient	S.E.
Constant	2,691.62∗∗∗	378.06	−0.52	4.08	0.26	0.16	−2,095,958∗∗	474,898
Linear
X12	−3,519.05∗∗∗	542.36	23.37∗∗	5.85	−0.46	0.23	3,469,777∗∗∗	681,289
X23	−4,986.43∗	2,286.62	13.22	24.65	−0.93	0.98	9,086,937∗∗	2,872,355
Quadratic
X12	1,272.14∗∗∗	222.09	−4.70	2.39	0.28∗∗	0.10	−1,196,938∗∗	278,986
X22	523.31	3,855.81	32.99	41.56	0.90	1.65	−3,899,058	4,843,506
Cross-product
X1X2	4,150.00∗	1,884.75	−18.33	20.32	0.90	0.81	−6,777,967∗	2,367,545

∗∗∗ Significant at p < 0.01.

∗∗ Significant at p < 0.05.

∗ Significant at p < 0.1.

¹⁾Standard error.

²⁾Concentration of polyglutamic acid.

³⁾Concentration of fucoidan.