Table 2.
Relative specific activities and enzyme kinetics of β-glucosidase from Lactobaillus antri (rBGLa).
| Chemicals | Relative activity (%) | Kinetic parameter | ||
|---|---|---|---|---|
| kcat (s -1 ) | K m (mM) | kcat/K m (mM -1 s -1 ) | ||
| pNPGa | 100 ± 1 | 407 ± 7 | 1.84 ± 0.07 | 221 ± 9 |
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| pNPG + 0.1mM cellobiose | 57.3 ± 1.5 | 432 ± 32 | 4.40 ± 0.57 | 98.1 ± 14.7 |
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| pNPGrb | 0.00123 ± 0.00006 | 0.213 ± 0.005 | 102 ± 6 | 0.00209 ± 0.00012 |
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| Liquiritin | 37.1 ± 0.3 | - | - | - |
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| Geniposide | 2.20 ± 0.04 | - | - | - |
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| Baicalin | 0.0261 ± 0.0002 | - | - | - |
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| Glycyrrhizin | 0.000190 ± 0.000103 | - | - | - |
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| Hesperidin | 0.0199 ± 0.0005 | - | - | - |
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| Neohesperidin | 0.00120 ± 0.00004 | - | - | - |
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| Naringin | 0.000866 ± 0.000090 | - | - | - |
a pNPG, p-nitrophenyl β-D-glucopyranoside; bpNPGr, p-nitrophenyl β-D-glucuronide.
For the measurement of relative activities, 1 mM substrates were reacted with 100 μg/mL rBGLa (pNPG, pNPGr, baicalin, glycyrrhizin, hesperidin, and naringin) and 0.1 μg/mL rBGLa (liquiritin and geniposide).