Optimization of Ultrasound-Assisted Extraction of Polyphenol Content from Zea mays Hairs (Waste)

Table 4

Effect estimation, statistical significance, and regression coefficient estimates for phenolic compounds extraction from Z. mays hairs.

Source	Coefficient	Degree of freedom	value
b0	14.186	—	<0.01
X1	1.450	1	<0.01
X2	0.771	1	0.0451
X3	−4.996	1	<0.01
X1-1	1.178	1	0.0302
X2-2	−0.714	1	0.207
X3-3	−0.664	1	0.271
X1-2	0.300	1	4.36
X1-3	0.200	1	12.4
X2-3	0.192	1	13.5