Applied Microbiology and Biotechnology

, Volume 61, Issue 3, pp 189–196 | Cite as

Aspergillus niger citric acid accumulation: do we understand this well working black box?

  • Levente Karaffa
  • Christian P. KubicekEmail author


This Mini-Review summarizes the current knowledge on the biochemical and physiological events leading to massive citric acid accumulation by Aspergillus niger under industrially comparable conditions, thereby particularly emphasizing the roles of glycolytic flux and its control, excretion of citric acid from the mitochondria and the cytosol, and the critical fermentation variables. The potential of novel techniques for metabolic analysis and genomic approaches in understanding this fermentation is also discussed.


Fermentation Citric Acid Gluconic Acid Pyruvate Carboxylase Alternative Oxidase 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors are cooperating within the framework of an Austro-Hungarian Intergovernmental Science and Technology Cooperation Programme (A-26/2000). The authors are grateful to Dr. Elisabeth Sandor for drawing Fig. 2.


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  1. 1.Division of Applied Biochemistry and Gene Technology, Institute of Chemical EngineeringTU WienViennaAustria
  2. 2.Department of Microbiology and Biotechnology, Faculty of SciencesUniversity of DebrecenDebrecenHungary

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