Nejvíce citovaný článek - PubMed ID 21086106
The development of microalgal biotechnology in the Czech Republic
Poly(3-hydroxybutyrate) (PHB) is a biobased and biodegradable polymer with properties comparable to polypropylene and therefore has the potential to replace conventional plastics. PHB is intracellularly accumulated by prokaryotic organisms. For the cells PHB functions manly as carbon and energy source, but all possible functions of PHB are still not known. Synechocystis (cyanobacteria) accumulates PHB using light as energy and CO2 as carbon source. The main trigger for PHB accumulation in cyanobacteria is nitrogen and phosphorous depletion with simultaneous surplus of carbon and energy. For the above reasons, obtaining knowledge about external factors influencing PHB accumulation is of highest interest. This study compares the effect of continuous light exposure and day/night (16/8 h) cycles on selected physiology parameters of three Synechocystis strains. We show that continuous illumination at moderate light intensities leads to an increased PHB accumulation in Synechocystis salina CCALA 192 (max. 14.2% CDW - cell dry weight) compared to day/night cycles (3.7% CDW). In addition to PHB content, glycogen and cell size increased, while cell density and cell viability decreased. The results offer new approaches for further studies to gain deeper insights into the role of PHB in cyanobacteria to obtain bioplastics in a more sustainable and environmentally friendly way.
- Klíčová slova
- PHB, Synechocystis, cell size, continuous illumination, day/night cycle, glycogen,
- Publikační typ
- časopisecké články MeSH
The following series of articles form a special issue organized by the Algatech Center of the Institute of Microbiology CAS dedicated to the memory of Dr. Ivan Šetlík.
- MeSH
- biopaliva dějiny MeSH
- dějiny 20. století MeSH
- dějiny 21. století MeSH
- fotosyntéza MeSH
- mikrobiologie dějiny MeSH
- sinice genetika metabolismus účinky záření MeSH
- Check Tag
- dějiny 20. století MeSH
- dějiny 21. století MeSH
- Publikační typ
- biografie MeSH
- historické články MeSH
- oslavné články MeSH
- Geografické názvy
- Československo MeSH
- Názvy látek
- biopaliva MeSH
- O autorovi
- Šetlík, Ivan
In this work, the key moments of the development of the so-called thin-layer cascades (TLC) for microalgae production are described. Development started at the end of the 1950s when the first generation of TLCs was set-up in former Czechoslovakia. Since, similar units for microalgae culturing, which are relatively simple, low-cost and highly productive, have been installed in a number of other countries worldwide. The TLCs are characterized by microalgae growth at a low depth (< 50 mm) and fast flow (0.4-0.5 m/s) of culture compared to mixed ponds or raceways. It guarantees a high ratio of exposed surface to total culture volume (> 100 1/m) and rapid light/dark cycling frequencies of cells which result in high biomass productivity (> 30 g/m2/day) and operating at high biomass density, > 10 g/L of dry mass (DW). In TLCs, microalgae culture is grown in the system of inclined platforms that combine the advantages of open systems-direct sun irradiance, easy heat derivation, simple cleaning and maintenance, and efficient degassing-with positive features of closed systems-operation at high biomass densities achieving high volumetric productivity. Among significant advantages of thin layer cascades compared to raceway ponds are the operation at much higher cell densities, very high daylight productivities, and the possibility to store the culture in retention tanks at night, or in unfavourable weather conditions. Concerning the limitations of TLCs, one has to consider contaminations by other microalgae that limit cultivation to robust, fast-growing strains, or those cultured in selective environments.
