Brief evaluation of the membrane and metabolic characteristics of heat-injured yeast with dielectrophoretic velocimetry

摘要

Constant monitoring and detailed examination of microbial metabolism have been required for the quality control in advanced bioindustry. Although microbial evaluation using dielectrophoresis should be an attractive scheme, the relationship with metabolism has not been understood well. In this paper, the membrane states and metabolic change of heat-injured Saccharomyces cerevisiae in a micro-cell were investigated using dielectrophoretic velocimetry under accurate temperature conditions. The treatment time at low temperature sensitively influenced the dielectrophoretic velocity of target yeast. Numerical analyses of the equivalent electrical circuit for bacterial cell revealed that the change in electrical parameters of cell membrane has a strong correlation with the transmembrane state and growth activity. These results suggest that the measurement of dielectrophoretic velocity would be available for rapid and simple metabolic evaluation of target microorganisms.