van Leeuwen Michiel, Heijnen Joseph J, Gardeniers Han, van der Wielen Luuk A M, van Gulik Walter M
Dept. of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
Biotechnol Prog. 2009 May-Jun;25(3):892-7. doi: 10.1002/btpr.145.
We developed and applied a conductometric method for the quantitative online measurement of the carbon dioxide (CO(2)) production during batch cultivations of Candida utilis on a 100-microL scale. The applied method for the CO(2) measurement consisted of absorption of the produced CO(2) from the exhaust gas of the microbioreactor in an alkali solution, of which the conductivity was measured on-line. The measured conductivity change of the alkali solution showed a linear relation with the total amount of CO(2) absorbed. After calibration of the CO(2) measurement system, it was connected to a well of a 96-well microtiter plate. The mixing in the well was achieved by a magnetic stirrer. Using online measurement of the CO(2) production during the cultivation, we show reproducible exponential batch growth of C. utilis on a 100-microL scale. The CO(2) production measurements obtained from the microcultivation were compared with the CO(2) production measurement in a 4-L bioreactor equipped with a conventional off-gas analyzer. The measurements showed that on-line measurement of the CO(2) production rate in microbioreactors can provide essential data for quantitative physiological studies and provide better understanding of microscale cultivations.
我们开发并应用了一种电导测量方法，用于在线定量测量100微升规模的产朊假丝酵母分批培养过程中二氧化碳（CO₂）的生成量。所应用的CO₂测量方法包括将微生物反应器废气中产生的CO₂吸收到碱性溶液中，并在线测量其电导率。测得的碱性溶液电导率变化与吸收的CO₂总量呈线性关系。在对CO₂测量系统进行校准后，将其连接到96孔微量滴定板的一个孔中。通过磁力搅拌器实现孔内混合。通过在线测量培养过程中CO₂的生成量，我们展示了100微升规模的产朊假丝酵母可重复的指数分批生长。将从微量培养中获得的CO₂生成量测量结果与配备传统废气分析仪的4升生物反应器中的CO₂生成量测量结果进行了比较。测量结果表明，微生物反应器中CO₂生成速率的在线测量可为定量生理学研究提供重要数据，并有助于更好地理解微尺度培养。
