Term: stationary phase (fermentation) https://doi.org/10.1351/goldbook.S05948 Definition: The phase of a culture of microorganisms or animal and plant cells cultured in vitro that follows the exponential growth phase and in which there is little or no growth. In some cases it is a phase of product formation, e.g. formation of secondary metabolites. Related Terms: 1) in vitro (http://doi.org/10.1351/goldbook.I03153). 2) secondary metabolites (http://doi.org/10.1351/goldbook.S05526). Source: PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 166 (https://doi.org/10.1351/pac199264010143) Citation: 'stationary phase (fermentation)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S05948 License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.