Abstract
A membrane probe was used to monitor the dissolved oxygen concentrations in continuous cultures of Candida utilis and Micrococcus roseus growing at low dissolved oxygen concentrations and various agitation levels. For the yeast fermentations, increasing the agitation level within the range of 0.1 to 0.3 w per liter lowered steady-state dissolved oxygen concentrations in the fermentor. The steady-state dissolved oxygen concentration in the fermentor was not influenced by the agitation level within the range of 0.3 to 1.8 w per liter. With M. roseus, no effect of agitation on steady-state dissolved oxygen concentrations in the fermentor was observed within the range of 0.1 to 1.8 w per liter. It was concluded that, under the conditions used, a measurable transfer barrier from the liquid to the yeast cells existed at agitation levels below 0.3 w per liter and that this barrier did not exist at agitation levels above 0.3 w per liter. The transfer barrier from the liquid to the yeast surface could be represented by a stagnant film of liquid 0.6 × 10-4 cm thick surrounding the cell at an agitation level of 0.10 w per liter. This film represented an oxygen concentration drop of 1.3 × 10-7 M from the bulk of the medium to the cells under the experimental conditions.
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Selected References
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- Button D. K., Garver J. C. Continuous culture of Torulopsis utilis: a kinetic study of oxygen limited growth. J Gen Microbiol. 1966 Nov;45(2):195–204. doi: 10.1099/00221287-45-2-195. [DOI] [PubMed] [Google Scholar]
- FINN R. K. Agitation-aeration in the laboratory and in industry. Bacteriol Rev. 1954 Dec;18(4):254–274. doi: 10.1128/br.18.4.254-274.1954. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Johnson M. J. Aerobic microbial growth at low oxygen concentrations. J Bacteriol. 1967 Jul;94(1):101–108. doi: 10.1128/jb.94.1.101-108.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Millington R. J. Diffusion Constant and Diffusion Coefficient. Science. 1955 Dec 2;122(3179):1090–1091. doi: 10.1126/science.122.3179.1090. [DOI] [PubMed] [Google Scholar]
- RICHARDS J. W. Studies in aeration and agitation. Prog Ind Microbiol. 1961;3:141–172. [PubMed] [Google Scholar]