One-Step Ultrafiltration Process for Separation and Purification of a Keratinolytic Protease Produced with Feather Meal

Table 2

Responses of 2³ experimental design.

Trial	predicted	experimental	Relative standard (%)	PF predicted	PF experimental	Relative standard (%)
1	80.5	79.3	−1.5	3.8	3.4	−11.2
2	40.1	41.3	3.0	2.3	2.1	−11.4
3	86.7	87.8	1.3	3.8	4.1	7.8
4	46.2	44.6	−3.7	2.3	1.9	−23.2
5	82.9	77.3	−7.3	3.7	3.6	−2.2
6	62.7	62.2	−0.9	3.4	3.5	1.7
7	82.9	82.4	−0.7	3.7	3.7	0.5
8	68.9	69.4	0.7	3.4	3.4	−1.2

; : enzyme recovery; PF: purification factor.