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02/2023 Methanol Measurement in Pichia Pastoris Fermentation: Inline Probes and Practical Tips

Pichia Pastoris fermentation is a frequently used method in biotechnology to produce proteins and enzymes. However, fermentation brings some challenges, especially in terms of methanol production. In this article, we will focus on specific methods for measuring methanol during Pichia Pastoris fermentation and provide practical tips for measuring methanol in the bioreactor.


Methanol Production in Pichia Pastoris Fermentation

During fermentation, Pichia Pastoris produces methanol to promote its growth. However, methanol is toxic and at high concentrations can inhibit or even kill the cells. Therefore, it is important to monitor and control methanol production during fermentation.

Inline Probes for Methanol Measurement

One method for monitoring methanol production during Pichia Pastoris fermentation is inline probes. Inline probes continuously measure the methanol content during fermentation. There are several types of inline probes that can be used for methanol measurement, including spectroscopic probes and electrochemical probes.

Spectroscopic Probes

Spectroscopic probes measure the methanol content based on absorption spectra in the infrared region. The method is sensitive and accurate, but requires careful calibration.

Electrochemical Probes

Electrochemical probes measure the methanol content based on electrochemical reactions. The method is easy to handle and requires only minimal calibration. However, it is important to regularly clean and calibrate the probes to obtain accurate results.

Practical Tips for Methanol Measurement in the Bioreactor

In addition to using inline probes, there are other practical tips for measuring methanol in the bioreactor. One option is to take samples during fermentation. The samples can then be analyzed in the laboratory to determine the methanol content. Although this method is time-consuming and requires additional work, it is more accurate than measuring with inline probes. Another option is to use reference substance solutions. Reference substance solutions are added at the beginning of fermentation and serve as a reference for methanol measurement. Using reference substance solutions can minimize deviations in measurements due to impurities or other factors.


Methanol measurement in Pichia Pastoris fermentation is an important factor in controlling methanol production and ensuring successful growth of cells and production of high-quality biotechnological products. The use of inline probes is a useful method for continuously measuring methanol content. However, it is important to carefully select the method and regularly clean and calibrate the probes. Additionally, practical tips such as controlling the bioreactor, regularly monitoring and cleaning the measurement equipment, and calibrating probes and solutions can help ensure successful and efficient Pichia Pastoris fermentations.