Takahashi Masato, Aoyagi Hideki
Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8572, Japan.
AMB Express. 2020 Apr 19;10(1):77. doi: 10.1186/s13568-020-01013-7.
The circulation direct monitoring and sampling system (CDMSS) is used as a monitoring device for CO and O concentrations of bypass type in shake-culture flask. The CDMSS could measure ka, an index for evaluating the performance of aerobic culture incubators, and k, an indicator of the degree of CO ventilation in the flask gas phase. We observed that cylindrical flasks provided a different culture environment, yielded a much higher k than the Erlenmeyer and Sakaguchi flasks, and yielded ka equivalent to that by Erlenmeyer flask by setting the ring-type baffle appropriately. Baffled cylindrical flask used for Escherichia coli K12 IFO3301 shake culture maintained lower CO concentrations in the headspace than conventional flasks; therefore, CO accumulation in the culture broth could be suppressed. Cell growth in baffled cylindrical flask (with ka equivalent to that of the Erlenmeyer flask) was about 1.3 and 1.4 times that in the Erlenmeyer and Sakaguchi flasks, respectively. This study focused on the batch culture at the flask scale and designed the headspace environment with low CO accumulation. Therefore, we conclude that redesign of flasks based on ka and k may contribute to a wide range of fields employing microorganism culture.
循环直接监测与采样系统（CDMSS）用作摇瓶培养中旁路型一氧化碳（CO）和氧气（O）浓度的监测装置。CDMSS能够测量ka（评估需氧培养箱性能的指标）以及k（摇瓶气相中CO通气程度的指标）。我们观察到，通过适当设置环形挡板，圆柱形摇瓶提供了不同的培养环境，其k值比锥形瓶和坂口瓶高得多，且ka值与锥形瓶相当。用于大肠杆菌K12 IFO3301摇瓶培养的带挡板圆柱形摇瓶，其顶部空间中的CO浓度低于传统摇瓶；因此，可以抑制培养液中CO的积累。带挡板圆柱形摇瓶（ka值与锥形瓶相当）中的细胞生长分别约为锥形瓶和坂口瓶中的1.3倍和1.4倍。本研究聚焦于摇瓶规模的分批培养，并设计了低CO积累的顶部空间环境。因此，我们得出结论，基于ka和k对摇瓶进行重新设计可能有助于广泛应用微生物培养的领域。
