Barbosa Maria J, Hoogakker Jeroen, Wijffels René H
Food and Bioprocess Engineering Group, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
Biomol Eng. 2003 Jul;20(4-6):115-23. doi: 10.1016/s1389-0344(03)00033-9.
Light availability inside the reactor is often the bottleneck in microalgal cultivation and for this reason much attention is being given to light limited growth kinetics of microalgae, aiming at the increase of productivity in photobioreactors. Steady-state culture characteristics are commonly used for productivity optimisation and for cell physiology studies in continuous cultures, and are normally achieved using chemostat cultivations. In the present study, we investigated the applicability of a new and dynamic cultivation method called acceleration-stat (A-stat) to microalgae cultivations where light is the limiting substrate. In the A-stat, the dilution rate is increased at a constant rate. This acceleration rate should be a compromise between a short cultivation time, in order to make it a fast process, and the metabolic adaptation rate of the microorganism to changes in the environment. Simulations of the A-stat were done with different acceleration rates to have an indication of the best rate to use. An A-stat was performed in a pilot plant bubble column (65 l) with Dunaliella tertiolecta as a model organism, and results showed that a pseudo steady state was maintained throughout the experiment. From this work, it was concluded that the A-stat can be used as a fast and accurate tool to determine kinetic parameters and to optimise any specific type of photobioreactor.
反应器内部的光照条件往往是微藻培养的瓶颈，因此，人们对微藻在光照受限情况下的生长动力学给予了高度关注，旨在提高光生物反应器的生产力。稳态培养特性通常用于连续培养中的生产力优化和细胞生理学研究，通常通过恒化器培养来实现。在本研究中，我们研究了一种名为加速恒化器（A-stat）的新型动态培养方法在以光为限制底物的微藻培养中的适用性。在A-stat中，稀释率以恒定速率增加。这种加速速率应该是在短培养时间（以便使其成为一个快速过程）和微生物对环境变化的代谢适应速率之间的一种折衷。对A-stat进行了不同加速速率的模拟，以确定最佳使用速率。在一个中试规模的鼓泡塔（65升）中以杜氏盐藻作为模式生物进行了A-stat实验，结果表明在整个实验过程中维持了一个伪稳态。从这项工作得出的结论是，A-stat可以用作一种快速且准确的工具来确定动力学参数并优化任何特定类型的光生物反应器。
