Kronusová Olga, Kaštánek Petr, Koyun Görkem, Kaštánek František, Brányik Tomáš
Department of Biotechnology, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague, Czech Republic.
EcoFuel Laboratories s.r.o., Ocelářská 9, 190 00 Prague, Czech Republic.
Microorganisms. 2022 Jul 21;10(7):1473. doi: 10.3390/microorganisms10071473.
The freshwater green microalgae, (CCALA 330), has the ability to produce extracellular polysaccharides (EPS). Conditions for optimum growth and EPS overproduction were determined in laboratory-scale tubular photobioreactors (PBR) with a working volume of 300 mL. Multiple limitations in nutrient supply were proven to be an effective method for EPS overproduction. Salinity stress was also applied to the culture, but no significant increase in EPS production was observed. The effects of different nitrogen sources were examined and the microalgae exhibited the fastest growth and EPS production in medium containing ammonium nitrate. Under determined optimal conditions, EPS concentration reached 10 g/L (71% of the total biomass) and a total biomass of 14 g/L at the end of 17 days cultivation. Pilot-scale cultivation was also carried out in a column type airlift photobioreactor (PBR) with a working volume of 60 L. A new and efficient methodology was developed for separating cells from the EPS-containing culture broth. Due to the strong attachment between cells and EPS, high-pressure homogenization was carried out before a centrifugation process. The EPS in the supernatant was subsequently purified using ultrafiltration. The green microalgae may therefore be appropriate for the commercial production of EPS.
淡水绿微藻（CCALA 330）具有产生胞外多糖（EPS）的能力。在工作体积为300 mL的实验室规模管式光生物反应器（PBR）中确定了最佳生长和EPS过量生产的条件。事实证明，营养供应的多重限制是EPS过量生产的有效方法。还对培养物施加了盐度胁迫，但未观察到EPS产量有显著增加。研究了不同氮源的影响，微藻在含有硝酸铵的培养基中生长最快且EPS产量最高。在确定的最佳条件下，培养17天后，EPS浓度达到10 g/L（占总生物量的71%），总生物量为14 g/L。还在工作体积为60 L的柱式气升光生物反应器（PBR）中进行了中试规模培养。开发了一种新的高效方法，用于从含EPS的培养液中分离细胞。由于细胞与EPS之间的强附着力，在离心过程之前进行了高压均质处理。随后使用超滤法纯化上清液中的EPS。因此，这种绿色微藻可能适合用于EPS的商业化生产。
