FTIR as an easy and fast analytical approach to follow up microbial growth during fungal pretreatment of poplar wood with Phanerochaete chrysosporium.

Since the determination of the fermentation kinetics is one of the main challenges in solid state fermentation, the quantitative measurement of biomass growth during microbial pretreatment by FTIR spectroscopy in Attenuated Total Reflectance mode was evaluated. Peaks at wave numbers of 1651 cm and 1593 cm showed to be affected during pretreatment of poplar wood particles by Phanerochaete chrysosporium MUCL 19343. Samples with different microbial biomass fractions were obtained from two different experiments, i.e., shake flask and fixed-bed reactor experiments. The glucosamine concentration was compared to the normalized absorbance ratio of the 1651 cm to 1593 cm peak, measured by FTIR-ATR, and resulted in a linear relationship. The application of a normalized absorbance ratio in function of time provided a graph that was similar to the microbial growth curve. Application of FTIR in ATR mode to follow-up kinetics during solid state fermentation seems to be a fast and easy alternative to laborious measurement techniques, such as glucosamine determination.