Table 2.
Effects of different metal ions, enzyme inhibitors, and organic solvents on LipSB 25-4 activity.
| Reagent | Residual activity (%) |
|---|---|
| Control | 100 |
| Metal ions | |
| ZnCl2 | 114.3 |
| CoCl2 | 74.6 |
| NiCl2 | 76.2 |
| NaCl | 54.0 |
| MnCl2 | 19.0 |
| MgCl2 | 0.0 |
| CaCl2 | 41.3 |
| CdCl2 | 57.1 |
| CuCl2 | 60.3 |
| Enzyme inhibitors | |
| EDTA | 94 |
| β-Mercaptoethanol | 108 |
| PMSF | 81 |
| Iodoacetic acid | 88 |
| SDS | 80 |
| Control | 100 |
| Organic solvents | |
| Methanol | 100.4 |
| Ethanol | 99.6 |
| Isopropanol | 91.1 |
| Acetone | 108.4 |
| Acetonitrile | 102.2 |
| DMSO | 96.9 |
| Butanol | 97.7 |
| Hexane | 99.5 |
| n-Heptane | 107.0 |
| Isooctane | 114.4 |
| Chloroform | 101.9 |
| Ethyl acetate | 108.4 |
Lipase preparation was incubated in the presence of 5 mM metal ions, 0.1% enzyme inhibitors, and 50% (v/v) organic solvents for 1 h at 30°C. Residual activity was measured using a standard method with p-NPP and the activity of enzyme without added metal ions, enzyme inhibitors, and organic solvent was taken as 100%.