Figure 3.

Effect of different concentrations of validamine added on the acarbose fermentation in batch culture by A. utahensis ZJB-08196. Symbols: shaded line bar:acarbose; black bar: impurity C; lined bar: DCW. Fermentations were carried out at 28°C and 200 rpm for 168 h in fermentation medium with the exogenous addition of validamine in the range from 0 to 160 mg/L prior to inoculation. The error bars in the figure indicate the standard deviations from three independent samples. *indicates statistic significance (P < 0.05) compared to control experiments without the addition of validamine.