藻類是小型的氣候保護者。即使在自然狀態下，它們也是極其高效的光合作用者，吸收的二氧化碳 (CO₂) 是陸地植物的十倍。在配備了適當感測器、控制技術和自動化的生物反應器中，藻類的效率可以提高到陸地植物的一百倍。這表明它們在發展氣候中和的循環經濟方面有著巨大的潛力。透過 PhotoBionicCell 研究專案，我們展示了未來工業生物化的潛在方法。
藻類可以自動培養，並透過生物反應器控制其生長。藻類液體被向上泵入表面收集器，在表面收集器中以均勻的流動分布，然後流回培養器。在這個循環過程中，藻類細胞透過葉綠體中的光合作用，將陽光、二氧化碳和水轉化為氧氣和化學能載體或有機可回收材料。這就是如何在一個封閉循環中培養生物質，這種方法非常高效，並且可節約資源。
成熟的開迴路和閉迴路控制系統與最先進的自動化元件相結合，為微生物提供了最佳條件。整合的充氣理念，確保空氣中的二氧化碳均勻分布到循環的生物流體中。
生物反應器面臨的一個主要挑戰是如何精確確定生物質的體積。我們的開發人員正在使用新創公司 Q.ANT 提供的量子技術感測器來實現這一點。它即時返回關於生物體生長的準確資訊。藉由微流體技術，藻類可自動連續地泵經 Festo 感測器。量子感測器能夠以光學方式檢測單個細胞，以便可以精確地確定生物量。此外，它還檢查細胞的活力。只有這樣，才有可能提前回應過程事件並對其進行調節。
Depending on the nutrients fed to the algae biomass, the products that are formed as part of the metabolic processes are fatty acids, colour pigments and surfactants. They can be used as the starting materials for the production of medicines, foodstuffs, plastics, cosmetics or fuels. Unlike petroleum-based products, biologically based end products can usually be biodegraded and, in keeping with an overall circular economy, recycled in a climate-neutral process.
Our researchers have also focused on the cultivation of the blue-green algae in their work for the PhotoBionicCell. They are producing colour pigments, omega-3 fatty acids and polyhydroxybutyrate (PHB). By adding other substances, the resulting PHB can be processed into a filament for 3D printing. Complex forms of sustainable plastic components or packaging can be manufactured in a short time with this modern production technology. For example, specific fastening clips made of bioplastic are installed in the PhotoBionicCell.
Many laboratory analyses have been done manually up to now. This is slow and can result in errors. The automation of such laboratory systems in the future will enable all required data to be read directly and in real time and researchers can concentrate better on their core tasks.
PhotoBionicCell will be completed by using in-house developed software. The dashboard allows multiple photobioreactors to be displayed with the current data situation and live images. Changes to parameters and the corresponding evaluations can be made around the clock and remotely. Users can thus respond to changes in the bioreactor at any time and, for example, start harvesting the product at the optimum time.
The digitised laboratory will be enhanced by an augmented reality application. A tablet can be used to augment reality and visualise the technical processes, process parameters and information about the processes inside the bioreactor.
Our developers are also using artificial intelligence (AI) to evaluate the data. This allows the bioreactor to be optimised for the propagation of the algae cultures or to maintain specified growth parameters with minimal energy input. It could also be used to forecast the service life of valves and other components. The use of digital twins created with the help of AI would also be possible. They could be used in future to simulate complete lifecycles of bioreactors and to show virtual images. The expected cell growth of different microorganisms could also be estimated with great accuracy before the physical setup up of a real system.
In addition to optimising laboratory facilities with automation and digitalisation, so-called artificial photosynthesis offers another promising perspective for cultivating biomass even more efficiently. With the Max Planck Institute for Terrestrial Microbiology Marburg as our partner, we have developed an automatic dispenser to improve the individual enzymes of photosynthesis. This requires testing thousands of variants of an enzyme. Compared to manual pipetting, the new automatic dispenser works much faster and eliminates errors. In addition, the automatic machine can be adapted to new tasks in seconds.
However, it's not just the individual building blocks of photosynthesis that can be optimised. The scientists are working on the digital optimisation of complete metabolic paths. This approach is referred to as synthetic biology. A metabolic path optimised on the computer is packed in synthetically manufactured cells, referred to as droplets. They have a diameter of around 90 micrometres and contain all the required enzymes and biocatalysts. This enables them, like their biological models, to absorb carbon dioxide using light energy.
Even though we are still in the middle of the development process, the potential for the future is already becoming clear today. If expertise in automation and basic research come together, the road to carbon-neutral production on an industrial scale will be implemented much faster. That is why we are conducting research in the field of biologisation.