Recovery of Bacillus licheniformis Alkaline Protease from Supernatant of Fermented Wastewater Sludge Using Ultrafiltration and Its Characterization

Table 5

Effect of metal ions on alkaline protease activity.

Metal ions (5 mm)	Residual alkaline protease activity (%)
Control	100
Ca^2+	125 ± 6.1
K^+	6 ± 0.26
Fe^2+	66 ± 3.1
Zn^2+	98 ± 4.7
Hg^2+	23 ± 1.1
Mg^2+	99 ± 4.8
Mn^2+	114 ± 5.5
Cu^2+	95 ± 4.6
Co^2 +	91 ± 4.4
Na^+	96 ± 4.7