The exponentially fed batch culture as a reliable alternative to conventional chemostats
The exponentially fed batch culture as a reliable alternative to conventional chemostats
复制标题
DOI：
10.4319/lom.2014.12.432
复制
发表时间：
2014-07-01
影响因子：
2.7
通讯作者：
Ptacnik, Robert
中科院分区：
文献类型：
--
作者：
Fischer, Robert;Andersen, Tom;Ptacnik, Robert
趋化菌和它们共同的替代品，半连续培养，在水生生态学中扮演着关键的角色。尽管恒化系统具有理论和概念上的优势，但它们的设置和操作可能具有挑战性。其中一个挑战是在不改变稀释率的情况下获得具有代表性的样品体积，另一个挑战是确保流出物构成恒化剂内容物的无偏损失。在这里，我们提出了一个特定的系统，指数补料批培养（EFB），作为一个经济的，简单的操作，虽然可靠的替代传统的化学调节剂。欧洲生物研究所在生物技术研究和工业生物工程方面享有盛誉。与传统的恒化器一样，EFB培养是一种连续培养方法。与传统的恒化器相比，它没有流出。为了确保恒定的稀释率和稳定的状态，新鲜培养基按当前培养量的比例连续供应。因此，培养体积和培养基供应率都随时间呈指数增长，直到采样时，体积恢复到初始状态。这允许在不干扰实验单元稳定状态的情况下采集大量样品。在这里，我们通过培养绿藻直到达到稳定状态，比较了指数投料分批培养与常规恒化器和半连续系统的性能。半连续系统与两种连续方法之间的差异最为显著。EFB和趋化剂的结果非常相似。然而，趋化器取样的偏差导致相对于EFB的生物量积累。
Chemostats and their common alternative, semicontinuous cultures, play a pivotal role as model systems in aquatic ecology. Despite the theoretical and conceptual advantages chemostat systems offer, they can be challenging to set up and operate. One such challenge is to obtain a representative sample volume without changing the dilution rate, another is to ensure that the outflow constitutes an unbiased loss of the chemostat contents. Here, we present a specific system, the exponentially fed-batch culture (EFB), as an economic, simply operable albeit reliable alternative to conventional chemostats. The EFB is well-known in biotechnological research and in industrial bioengineering. Like a conventional chemostat, the EFB culture is a continuous culture method. In contrast to a conventional chemostat, there is no outflow. To ensure a constant dilution rate and therefore steady state, fresh medium is continuously supplied proportional to the current culture volume. Hence culture volume and medium supply rate both increase exponentially with time until sampling, when the volume is set back to the initial state. This allows taking large sample volumes without disturbing the steady state of the experimental unit. Here we compare the performance of the exponentially fed-batch culture with a conventional chemostat and a semicontinuous system by growing a green algae until steady state is reached. Most pronounced differences were found between semicontinuous system and the two continuous methods. Results from the EFB and chemostat were very similar. However, a bias in the sampling of the chemostat resulted in accumulation of biomass relative to the EFB.