Bioprocessing of “Hair Waste” by Paecilomyces lilacinus as a Source of a Bleach-Stable, Alkaline, and Thermostable Keratinase with Potential Application as a Laundry Detergent Additive: Characterization and Wash Performance Analysis

Table 4

Effect of protease inhibitors, metal ions, detergents, and solvents on protease activity (data are given as Residual activity (%) ± SD).

Chemical none	Concentration	Residual activity (%); 100
Inhibitor
PMSF	2 mM	7.0 ± 0.0
Iodoacetate	10 mM	95.1 ± 4.7
EDTA	5 mM	99.6 ± 6.3
1,10-Phenantroline	1 mM	100 ± 0.2
Pepstatin A	100 𝜇g/mL	87.5 ± 5.5
Metal ion
Mg^2+	1 mM	105.0 ± 1.2
Zn^2+	1 mM	92.8 ± 1.4
Ca^2+	1 mM	102.9 ± 0.5
Hg^2+	1 mM	6.0 ± 0.6
Detergents
Triton X-100	0.5% (v/v)	97.7 ± 2.7
Tween 20	0.5% (v/v)	98.5 ± 2.0
SDS	0.5% (v/v)	75.9 ± 3.4
Bleaching agent
	1% (w/v)	140 ± 2.3
H2O2	2%	137 ± 0.3
	3%	122.7 ± 4.0
	0.2% (w/v)	99.7 ± 2.4
Sodium perborate	0.5%	97.6 ± 0.9
	1.0%	90.8 ± 2.0
Solvent
DMSO	1% (v/v)	106.0 ± 1.6
Ethanol	1% (v/v)	105.4 ± 4.0
Methanol	1% (v/v)	117.0 ± 2.9
Isopropanol	1% (v/v)	98.9 ± 1.7