Optimization of Fermentation Conditions and Media for Production of Glucose Isomerase from Bacillus megaterium Using Response Surface Methodology

Figure 6

The effect of the concentration of peptone on glucose isomerase production. Peptone is the second nitrogen source for bacterial growth and enzyme synthesis; therefore, the concentration of peptone may affect the glucose isomerase activity. In this study, the concentration of peptone was increased from 0 to 1% along with an elevation of enzyme activity from 0.182 ± 0.002 to 0.263 ± 0.004 U/mg biomass (). Then, the enzyme activity decreased along with the higher increase of peptone concentration (1.5–2.5%). Therefore, we chose 1% peptone as the optimal concentration to produce glucose isomerase.