Joshi Jnanada Shrikant, Fladung Laura, Kruse Olaf, Patel Anant
Bielefeld Institute of Applied Materials Research, Hochschule Bielefeld-University of Applied Sciences and Arts, 33619 Bielefeld, Germany.
Faculty of Biology, Bielefeld University, 33615 Bielefeld, Germany.
Microorganisms. 2025 Mar 5;13(3):606. doi: 10.3390/microorganisms13030606.
Microalgal biotechnology is gaining attention due to its potential to produce pigments, lipids, biofuels, and value-added products. However, challenges persist in terms of the economic viability of microalgal lipid production in photobioreactors due to slow growth rates, expensive media, complex downstream processing, limited product yields, and contamination risks. Recent studies suggest that co-cultivating microalgae with bacteria can enhance the profitability of microalgal bioprocesses. Immobilizing bacteria offers advantages such as protection against shear forces, the prevention of overgrowth, and continuous product secretion. Previous work has shown that biopolymeric immobilization of enhances 2,3-butanediol production. In this study, a novel co-fermentation process was developed by exploiting the chemical crosstalk between a freshwater microalga , also known as , and an immobilized plant-growth-promoting bacterium, . This co-cultivation resulted in increased metabolite production, with a 1.5-fold increase in the bacterial 2,3-butanediol concentration and a 3-fold increase in the microalgal growth rates compared to these values in free-cell co-cultivation. Moreover, the co-culture with the immobilized bacterium exhibited a 5-fold increase in the photosynthetic pigments and a 3-fold increase in the microalgal lipid concentration compared to these values in free-cell co-cultivation. A fixed bed photobioreactor was further constructed, and the co-cultivation bioprocess was implemented to improve the bacterial 2,3-butanediol and microalgal lipid production. In conclusion, this study provides conclusive evidence for the potential of co-cultivation and biopolymeric immobilization techniques to enhance 2,3-butanediol and lipid production.
微藻生物技术因其在生产色素、脂质、生物燃料和增值产品方面的潜力而受到关注。然而，由于生长速度缓慢、培养基昂贵、下游加工复杂、产品产量有限以及存在污染风险，光生物反应器中微藻脂质生产的经济可行性方面仍然存在挑战。最近的研究表明，将微藻与细菌共培养可以提高微藻生物过程的盈利能力。固定化细菌具有诸如抵御剪切力、防止过度生长和持续分泌产物等优点。先前的工作表明，生物聚合物固定化可提高2,3-丁二醇的产量。在本研究中，通过利用一种淡水微藻（也称为 ）与一种固定化的促进植物生长的细菌 之间的化学相互作用，开发了一种新型的共发酵工艺。与自由细胞共培养相比，这种共培养导致代谢产物产量增加，细菌2,3-丁二醇浓度增加了1.5倍，微藻生长速率增加了3倍。此外，与固定化细菌的共培养相比，自由细胞共培养中的光合色素增加了5倍，微藻脂质浓度增加了3倍。进一步构建了固定床光生物反应器，并实施了共培养生物过程以提高细菌2,3-丁二醇和微藻脂质的产量。总之，本研究为共培养和生物聚合物固定化技术在提高2,3-丁二醇和脂质产量方面的潜力提供了确凿证据。
