Relation between growth dynamics and diffusional limitations in Saccharomyces cerevisiae cells growing as entrapped in an insolubilised gelatin gel

Flow-cytometric analysis was employed to investigate growth dynamics of a y east cell population immobilised in an insolubilised gelatin gel by means o f the quantitative determination of the average protein content per cell. T his analysis was carried out on both the immobilised cell population consid ered as a whole and the subpopulations colonising the gelatin matrix at dif ferent depths. The results show that growth of the gelatin-immobilised yeas t population was affected by the existence of a gradient of nutrient concen trations through the matrix and are in agreement with the unsteady-state di ffusion model employed for the description of glucose transfer in the gel. (C) 2001 Federation of European Microbiological Societies. Published by Els evier Science B.V. All rights reserved.