Genuscandida berkhout

Two strains ofCandida albicans, one of low, the other of high virulency, were cultivated in a semi-synthetic medium with glucose concentrations 3 and 0.4%. The validity of the mathematical theory of single stage continuous cultivation was verified. The standard hyperbolic course of the curves expressing mutual relations between the substrate and microorganisms concentrations (S and X respectively), and dilution rate D gets lost at the concentration of 3%. For the 0.4% glucose concentration, reasonable agreement between theoretical and experimental values was obtained at lower dilution rates, so far as the yield coefficient remained constant. At greater dilution rates D, the yield coefficient decreased and the experimental values deviated from the theoretical ones. Specific rate of oxygen consumption\(Q_{O_2 } \), specific rate of CO₂ formation\(Q_{CO_2 } \), the specific rate of the substrate consumption q, alcohol formation P and total acids formation have been followed. By calculation, the smallest dilution rate “a”, was determined for which steady state conditions are still valid. This magnitude has been experimentally verified for the strain “19”. The steady state conditions are possible at 0.4% glucose concentration for the following range of dilution rates D: Strain “19” from D=0.0039 to 0.42 h^?1 strain “109” from D=0.003 to 0.41 h^?1. All calculated values were evaluated by statistical t-test. Significant differences between strains have been found for the yield coefficient at the concentration of 0.4%. This difference is probably caused by a small difference in the initial concentration of glucose S₀.