Growth behavior of Chinese hamster ovary cells in a compact loop bioreactor: 1. Effects of physical and chemical environments

Chinese hamster ovary (CHO) cells were cultivated in a compact loop bioreactor using MEM-α medium supplemented with 10% fetal calf serum. Effects of physical and chemical environments, i.e., pH in the medium, stirring speed of impellers, temperature and partial pressure of oxygen ( pO 2) upon growth of suspended cells in the bioreactor were determined in batch cultures. Growth behavior was characterized by specific rates of growth (μ), glucose consumption ( q G) and lactate production ( q L), and the yield coefficients (cell yield from glucose, Y X/G, and lactate yield from glucose, Y L/G). An effect of medium osmolality was also evaluated with T-flask monolayer cultivation. The best growth was observed at pH 7.6, 37°C, 400 rpm, 50–100% saturation with oxygen and 320 mOsmol kg −1. Corresponding to the previous work with a human melanoma cell line, the sophisticated cultivation and process control systems have been improved for CHO cells.