On-line biomass monitoring by capacitance measurement

摘要: Abstract An in-situ, steam-sterilizable capacitance probe was used to follow the biomass concentration on-line, in bioreactors from 20 2000 l total volume. Microbial cultures of Saccharomyces cerevisiae, Pichia pastoris and Streptomyces virginiae were grown batch fed-batch culture both defined complex media order demonstrate wide dynamic operating range instrument. A linear correlation found between on-line measurement off-line measurements (optical density, OD620; packed mycelial volume, PMV; X, colony forming units, CFU ml−1) for concentrations (dry cell weight) up 30 g l−1 (St. virginiae), 106 (S. cerevisiae) 89 (P. pastoris). The slightly influenced by variations agitation speed strong extraneous radio frequencies. specific constant (Cs) all microbial cells which dependent on viability size. Cs easy calculate using an estimation concentration. Biomass Monitor proved suitable precise monitoring homogeneous (uni-cellular) heterogeneous (mycelial) bioreactors.