Fluorescence monitoring of immobilzed microorganisms in cultures

Gel Entrapment and Micro-Encapsulation: Methods, Applications and Engineering Principles

“…Eikmeier et al, 1984;Bailliez et al, 1985;Godia et al, 1987;Marin-Iniestaet al, 1988;Barbotin et al, 1990b Willaert and Baron, 1993 growth rate, spatial invasive biomass distribution Membrane reactor Measurements of On-line and in situ substrate and measurement product Hannoun and Stephanopoulos, 1990;Willaertetal., 1990;De Backer et al, 1992 Fluorescent measurements of intracellular NADH of S. cerevisiae cells grown on a gelatine surface and free cells have been performed (Doran and Bailey, 1987): dynamic responses of NADH for immobilised cells were different from those of yeast cells grown in suspension, indicating that immobilisation affects cellular regulation and control functions within the glycolytic pathway. The influence of the immobilisation of S. cerevisiae in Caalginate has also been studied by using on-line measurements of NADH fluorescence (Müller et al, 1988;Anders et al, 1990;Scheper et al, 1990). A comparison of the immobilised and suspended cell system showed that the rate of ethanol consumption during an aerobic fermentation was significantly slower for the immobilised cells.…”

Real and pseudo oxygen gradients in Ca‐alginate beads monitored during polarographic Po2‐measurements using Pt‐needle microelectrodes

“…24 In all batch-type experiments the median bead diameter was 2 mm and the cells were grown in medium I1 on 1% (w/v) glucose under aerobic conditions at 30°C and pH 4. The ratio a1ginate:medium was 1:20 and the initial cell concentration yielded in about 5.0 g dry WUL gel.…”

“…Two different experiments with gel-immobilized cells were performed: (1) cultivation of immobilized yeast in a shaker flask on a rotary shaker; and (2) cultivation in a packed bed reactor (PBR) system. 24 In all batch-type experiments the median bead diameter was 2 mm and the cells were grown in medium I1 on 1% (w/v) glucose under aerobic conditions at 30°C and pH 4. The ratio a1ginate:medium was 1:20 and the initial cell concentration yielded in about 5.0 g dry WUL gel.…”

Determination of yeast glycogen content by individual cell spectroscopy using image analysis

“…Further, image analysis systems have been coupled to automatic sampling systems providing near real-time data throughout the entire course of the fermentations (Zalewski and Buchholz, 1996). Characterization of yeast during immobilized (Muller et al, 1988) and free-cell (Suhr et al, 1995) fermentations has been reported using fluorescent probes and cameras installed in the wall of the fermentation vessel. Image analysis techniques have also been used to study the effect of cell morphology on the filtration characteristics of fermentation broths (McCarthy et al, 1998).…”