Departamento de Bioingeniería, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal. 510-3, 62250, Cuernavaca, Mor., México.
Cytotechnology. 1996 Jan;22(1-3):225-37. doi: 10.1007/BF00353943.
Dissolved oxygen tension and oxygen uptake rate are critical parameters in animal cell culture. However, only scarce information of such variables is available for insect cell culture. In this work, the effect of dissolved oxygen tension (DOT) and the utility of on-line oxygen uptake rate (OUR) measurements in monitoring Spodoptera frugiperda (Sf9) cultures were determined. Sf9 cells were grown at constant dissolved oxygen tensions in the range of 0 to 30%. Sf9 metabolism was affected only at DOT below 10%, as no significant differences on specific growth rate, cell concentration, amino acid consumption/production nor carbohydrates consumption rates were found at DOT between 10 and 30%. The specific growth rate and specific oxygen uptake rate followed typical Monod kinetics with respect to DOT. The calculated μ(max) and [Formula: see text] max were 0.033 h(-1) and 3.82×10(-10) mole cell(-1)h(-1), respectively, and the corresponding saturation constants were 1.91 and 1.57%, respectively. In all aerated cultures, lactate was consumed only after glucose and fructose had been exhausted. The yield of lactate increased with decreasing DOT. It is proposed, that an 'apparent' DOT in non-instrumented cultures can be inferred from the lactate yield of bioreactors as a function of DOT. Such a concept, can be a useful and important tool for determining the average dissolved oxygen tension in non-instrumented cultures. It was shown that the dynamic behavior of OUR can be correlated with monosaccharide (fructose and glucose) depletion and viable cell concentration. Accordingly, OUR can have two important applications in insect cell culture: for on-line estimation of viable cells, and as a possible feed-back control variable in automatic strategies of nutrient addition.
溶解氧张力和耗氧速率是动物细胞培养的关键参数。然而，昆虫细胞培养的此类变量信息却很少。在这项工作中，确定了溶解氧张力 (DOT) 的影响以及在线耗氧速率 (OUR) 测量在监测 Spodoptera frugiperda (Sf9) 培养物中的用途。 Sf9 细胞在 0 至 30%的范围内的恒定溶解氧张力下生长。只有在 DOT 低于 10%时， Sf9 代谢才会受到影响，因为在 DOT 为 10%至 30%之间时，比生长速率、细胞浓度、氨基酸消耗/产生以及碳水化合物消耗率没有明显差异。比生长速率和比耗氧速率均遵循典型的 Monod 动力学与 DOT 有关。计算出的 μ(max) 和 [Formula: see text] max 分别为 0.033 h(-1) 和 3.82×10(-10) mole cell(-1)h(-1)，相应的饱和常数分别为 1.91%和 1.57%。在所有充气培养物中，只有在葡萄糖和果糖耗尽后才消耗乳酸。随着 DOT 的降低，乳酸的产率增加。有人提出，在没有仪器的培养物中，可以根据生物反应器中乳酸的产率与 DOT 的关系推断出“表观”DOT。这种概念可以作为确定非仪器化培养物中平均溶解氧张力的有用且重要的工具。结果表明，OUR 的动态行为可以与单糖（果糖和葡萄糖）耗尽和活细胞浓度相关联。因此，OUR 在昆虫细胞培养中有两个重要的应用：在线估计活细胞，以及作为自动添加营养物策略中的反馈控制变量。
