Related Experiment Video
Updated: Aug 30, 2026

Medium Preparation for the Cultivation of Microorganisms under Strictly Anaerobic/Anoxic Conditions
Published on: August 15, 2019
Factors affecting constancy of acetate concentration and correct determination of methanogenic activity in pH-stat
1Laboratorium für Technische Chemie, Eidgenössische Technische Hochschule, HCI F 112, Zürich, Switzerland. marek.moesche@tech.chem.ethz.ch
Abstract:
The determination of methanogenic activity with a pH-stat titration bioassay is evaluated utilising a mathematical model of this system. For given kinetic parameters and experimental conditions the model calculates the development of titrant flow and acetate concentration during experiments. Simulations of experiments under various conditions are compared. They show that the original method inherently causes a strong drift of acetate concentration during the experiments and a misestimation of methanogenic activity. As a solution to these disadvantages the addition of sodium hydroxide to the titrant and a careful control of pH during flushing the reactor with gas prior to the experiment are recommended. In this way a better constancy of acetate concentration and a more accurate determination of methanogenic activity should be achievable. The accuracy of this method is limited by the stability of pH-electrode calibration parameters.
Related Concept Videos
Titration of a Weak Acid with a Strong Base
Solution Composition During Acid/Base Titrations
The α0 and α1 values represent the...
Titration of a Weak Acid with a Weak Base
As a result, there is no simple...
Common Ion Effect
Factors Influencing Microbial Growth: pH

