Amino acids profiles in a ph-auxostat

Authors

  • Yen-Han Lin,

    Corresponding author
    1. Department of Chemical Engineering, 110 Science Place, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
    • Department of Chemical Engineering, 110 Science Place, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
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    • joint professorship with Saskatchewan Research Council, SK, Canada

  • Wei Ji

    1. Department of Chemical Engineering, 110 Science Place, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
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Abstract

The proportions of amino acids changed dramatically in a pH-auxostat as the dilution rate was increased by feeding a medium with a low buffering capacity. A brief period of auxostatic culturing converts an elective mixed culture to a nearly pure culture, and this selection is accelerated by lowering the buffering capacity. As the specific growth rate was increased, the organisms utilized some of amino acids partially and/or completely, while others were essentially unchanged or even enriched. Such an enrichment effect was greatest at the highest specific growth rate.

Abstract

Les proportions d'acides aminès changent considèrablement dans un pH-auxostat alors que la vitesse de dilution augmente si on alimente le milieu avec une faible capacitè tampon. Une breáve pèriode de mise en culture auxostatique convertit une culture mixte èlective en une culture presque pure, et cette sèlection est accèlèrèe si on abaisse la capacitè tampon. Lorsque la vitesse de croissance spècifique est augmentèe, les organismes utilisent certains des acides aminès partiellement et/ou compleátement, tandis que d'autres restent essentiellement inchangès ou měme enrichis. Cet effet d'enrichissement est měme plus important à la vitesse de croissance spècifique la plus grande.

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