The nature and composition of buffer solution have to be considered carefully since they play an important role in controlling the properties of the enzyme and the analyte [16]. The buffers used in the assay procedure included acetic acid/acetate of pH 3.6-5.6; citric acid/potassium citrate of pH 3.6-5.6; Potassium dihydrogenphosphate/dipotassium hydrogen phosphate with pH range of 6.0-7.5; Potassium dihydrogenphosphate/Sodium hydroxide (KH2PO4/NaOH) of pH ranging from 6.0-8.0 and tris buffer of pH 9.8. The corresponding pH-dependent response curve is shown in Fig. 2. The highest activity of the enzyme was observed in 100 mM KH2PO4/NaOH buffer of pH 7.8. Hence, 100 mM KH2PO4/NaOH buffer of pH 7.8 was taken as the optimal reaction buffer for subsequent analysis.