SIRE-TECHNOLOGY - PART III - GLUCOSE MONITORING DURING FERMENTATION OF A LIGNOCELLULOSIC HYDROLYSATE BY SACCHAROMYCES-CEREVISIAE EMPLOYING A DIFFERENTIAL AMPEROMETRIC BIOSENSOR

A biosensor with an Injectable recognition element (SIRE-biosensor) wa s used to measure the glucose concentration in undiluted samples from a fermentation of a hardwood hydrolysate. Glucose oxidase (1 mg/ml, 18 4.9 U/ml) was used as the recognition element in combination with an a mperometric transducer. The results obtained with the SIRE-biosensor s howed a good correlation to those obtained with an established analyti cal procedure (HPLC). The correlation coefficient and regression line between the two methods were r = 0.996 and y = 0.86x - 0.21. Thus, the results from the SIRE-biosensor were slightly lower than those obtain ed with HPLC, and the reasons herein are discussed. The SIRE-biosensor had a sampling frequency of 12 samples per hour, whereas the HPLC onl y allowed measurements of 1.2 samples per hour and required dilution o f the samples. Additionally, the SIRE-biosensor measurements do not re quire any sample preparation, thus suggesting that the sensor can be u sed for in situ monitoring of fermentation processes.