May 1, 1996

Axenic mass cultivation of the free-living soil amoeba, Acanthamoeba castellanii in a laboratory fermentor

Antonie van Leeuwenhoek
P H WeekersG D Vogels

Abstract

Axenic mass cultivation of Acanthamoeba castellanii in laboratory fermentors (141) yielded after 20 days approximately 3 g cells (wet weight). After a short lag phase amoebal cell numbers increased exponentially to a maximum of 3.5 x 10(5) cells per ml until cell death occurred after 20 days. Optical density and protein concentrations revealed identical patterns. During amoebal growth only 12-19% of the initially added glucose (100 mM) as sole carbon source was used. Large amounts of ammonia (1 g in 10.51 culture volume) were excreted into the medium which subsequently raised the pH from 6.6 to 7.7, and from 6.6 to 6.8 in 2 and 20 mM buffered media, respectively. Growth inhibition and cell death could not be explained by a depletion of glucose or oxygen limitations during growth. The production of ammonia had a growth inhibitory effect, however, the sudden termination of the exponential growth phase and cell death could not be explained by the toxic influence of ammonia only.

Mentioned in this Paper

Buffers
Dioxygen
Acanthamoeba castellanii
Amoeba genus
Cell Count
Anhydrous Dextrose
Blood Ammonia Measurement
Ammonia Inhalants
Metabolic Inhibition
Ammonia

About this Paper

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