•High cell density of Scenedesmus incrassatulus biomass was achieved in heterotrophic culture.•Vitamins were suggested as regulatory factor in enhancing pigment synthesis.•Two stage ...hetrotrophy/photoinduction process was employed for S. incrassatulus culture.•Two stage hetrotrophy/photoinduction process improved the biomass and lutein productivity.
A biomass production process including two stages, heterotrophy/photoinduction (TSHP), was developed to improve biomass and lutein production by the green microalgae Scenedesmus incrassatulus. To determine the effects of different nitrogen sources (yeast extract and urea) and temperature in the heterotrophic stage, experiments using shake flask cultures with glucose as the carbon source were carried out. The highest biomass productivity and specific pigment concentrations were reached using urea+vitamins (U+V) at 30°C. The first stage of the TSHP process was done in a 6L bioreactor, and the inductions in a 3L airlift photobioreactor. At the end of the heterotrophic stage, S. incrassatulus achieved the maximal biomass concentration, increasing from 7.22gL−1 to 17.98gL−1 with an increase in initial glucose concentration from 10.6gL−1 to 30.3gL−1. However, the higher initial glucose concentration resulted in a lower specific growth rate (μ) and lower cell yield (Yx/s), possibly due to substrate inhibition. After 24h of photoinduction, lutein content in S. incrassatulus biomass was 7 times higher than that obtained at the end of heterotrophic cultivation, and the lutein productivity was 1.6 times higher compared with autotrophic culture of this microalga. Hence, the two-stage heterotrophy/photoinduction culture is an effective strategy for high cell density and lutein production in S. incrassatulus.
A xanthate-based, solvent free, homolytic substitution on selected substituted pyrrole systems is described. Additionally, a practical entry for the rapid construction of pyrrole fused systems using ...this solventless radical addition followed by a double nucleophilic alkylation sequence, is also reported.
Growth of lulo (Solanum quitoense Lam.) plants affected by salinity and substrate Flórez, Sandra Liliana(Universidad Nacional de Colombia Facultad de Agronomía); Lasprilla, Diego Miranda(Universidad Nacional de Colombia Facultad de Agronomía); Chaves, Bernardo(Universidad Nacional de Colombia Facultad de Agronomía) ...
Revista Brasileira de Fruticultura,
06/2008, Letnik:
30, Številka:
2
Journal Article
Odprti dostop
The effects of 0, 30 and 60 mM NaCl and substrates (red peat, sand or 3:1:1 w/w mixture of peat, sand, or soil) on vegetative growth of lulo, an Andean fruit species, during 12 weeks were studied. ...The experiment was carried out by using 2000 cm³ of polypropylene plastic pots under greenhouse conditions. Plant height, number of leaves and nodes, leaf area, total plant dry matter (DM), and shoot/root ratio were evaluated. With the increase of salt concentration, the plant height, the number of leaves and nodes, the leaf areas and plant dry mass DM decreased, whereas shoot/root ratio increased. Sand grown lulo plants were most affected by salinity and presented total mortality at 60 mM NaCl. On the other hand, plants held either in peat or in substrate mixture developed larger height, greater leaf and node numbers, higher leaf area and dry matter content. Shoot/root ratio in control (soil) and sand-grown plants (30 mM NaCl) was lower.
Durante 12 semanas, foi estudado o efeito de 0; 30 e 60 mM de NaCl e dos substratos (turfa vermelha, ou de mistura de turfa, areia, ou solo 3:1:1 w/w) sobre o desenvolvimento vegetativo de lulo, uma espécie de fruto originária dos Andes. O experimento foi feito em condições de casa de vegetação, utilizando vasos plásticos de polipropileno de 2.000 cm³. Foram avaliadas as mudanças em altura de planta, número de folhas e nós, área foliar, massa seca total da planta (DM) e relação raiz parte aérea. Com o incremento da concentração salina, a altura de planta, o número de folhas e de nós, as áreas foliares e a massa seca da planta diminuíram, enquanto a relação parte aérea/raiz aumentou. As plantas de lulo cultivadas em areia foram as mais afetadas pela salinidade e apresentaram mortalidade total aos 60 mM de NaCl. Assim, as plantas mantidas em turfa ou na mistura de substratos apresentaram maiores alturas, número de folhas e nós, áreas foliares e conteúdo de massa seca. A relação parte aérea/raiz foi mais baixa no controle (solo) e nas plantas cultivadas em areia (30 mM NaCl).
The effects of 0, 30 and 60 mM NaCl and substrates (red peat, sand or 3:1:1 w/w mixture of peat, sand, or soil) on vegetative growth of lulo, an Andean fruit species, during 12 weeks were studied. ...The experiment was carried out by using 2000 cm³ of polypropylene plastic pots under greenhouse conditions. Plant height, number of leaves and nodes, leaf area, total plant dry matter (DM), and shoot/root ratio were evaluated. With the increase of salt concentration, the plant height, the number of leaves and nodes, the leaf areas and plant dry mass DM decreased, whereas shoot/root ratio increased. Sand grown lulo plants were most affected by salinity and presented total mortality at 60 mM NaCl. On the other hand, plants held either in peat or in substrate mixture developed larger height, greater leaf and node numbers, higher leaf area and dry matter content. Shoot/root ratio in control (soil) and sand-grown plants (30 mM NaCl) was lower.Durante 12 semanas, foi estudado o efeito de 0; 30 e 60 mM de NaCl e dos substratos (turfa vermelha, ou de mistura de turfa, areia, ou solo 3:1:1 w/w) sobre o desenvolvimento vegetativo de lulo, uma espécie de fruto originária dos Andes. O experimento foi feito em condições de casa de vegetação, utilizando vasos plásticos de polipropileno de 2.000 cm³. Foram avaliadas as mudanças em altura de planta, número de folhas e nós, área foliar, massa seca total da planta (DM) e relação raiz parte aérea. Com o incremento da concentração salina, a altura de planta, o número de folhas e de nós, as áreas foliares e a massa seca da planta diminuíram, enquanto a relação parte aérea/raiz aumentou. As plantas de lulo cultivadas em areia foram as mais afetadas pela salinidade e apresentaram mortalidade total aos 60 mM de NaCl. Assim, as plantas mantidas em turfa ou na mistura de substratos apresentaram maiores alturas, número de folhas e nós, áreas foliares e conteúdo de massa seca. A relação parte aérea/raiz foi mais baixa no controle (solo) e nas plantas cultivadas em areia (30 mM NaCl).
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