MONITORING BIOMASS AND GLYCEROL IN AN ESCHERICHIA-COLI FERMENTATION USING NEAR-INFRARED SPECTROSCOPY

Near-infrared spectroscopy was used to determine biomass and glycerol concentrations in E. coli whole broth fermentation samples. For dry ce ll weight, a standard error of prediction (SEP) of 0.2 g/L and correla tion coefficient (r) of 0.991 were obtained. The SEP and r for glycero l, carbon nutrient, were 0.3 g/L and 0.979, respectively. Off-line ana lysis was accomplished with 2 minutes of sampling and therefore provid es the opportunity to monitor fermentations quickly enough to permit i n-process development and troubleshooting.