Microalgae have received increasing attention as one of the most promising feedstocks in development new healthier food products and different strategies been attempted to improve their growth. However, high production costs low productivities, commonly associated with photoautotrophic growths, are still a big challenge. In this study, two-step optimization strategy was carried out order maximi...

Heterotrophic (phagotrophic) flagellates are key components of planktonic food webs in freshwater and marine ecosystems because they are the main consumers of bacteria. Although they are ubiquitous in aquatic ecosystems, they were numerically undetectable in turbid glacier-fed lakes. Here we show that glacial particles had negative effects on the survival and growth of heterotrophic flagellates...

Many of the current greenhouse based intensive marine shrimp production systems have used photoautotrophic algae systems to control inorganic nitrogen accumulation. A second strategy of nitrogen control used in some indoor intensive recirculating production systems is using large fixed-film bioreactors. This option utilizes chemosynthetic autotrophic bacteria, Ammonia Oxidizing Bacteria (AOB) a...

Volatile fatty acids (VFAs) produced by fermentative bacteria can be used instead of high value carbohydrates like glucose to reduce the costs associated mixotrophic microalgal cultivation. This process is however limited a poor assimilation butyrate and low tolerance microalgae VFA concentrations. In this study, 10 strains, isolated from local natural environments or selected culture collectio...

Recent field studies indicate that dinoflagellates are key degraders of copepod fecal pellets. This study is the first to publish direct evidence of pellet grazing by dinoflagellates. Feeding and growth on copepod fecal pellets were studied for both heterotrophic (4 species) and mixotrophic dinoflagellates (3 species) using a combination of classic incubation experiments and video recordings of...

Here, we investigated effects of copper (Cu) and chromium (Cr) toxicity on two contrasting strains of Euglena gracilis, with and without chloroplasts, grown in culture media promoting either phototrophic or heterotrophic growth. This led to insights into Cr/Cu toxicity mechanisms and into the regulation of phototrophic vs heterotrophic metabolism. Our data strongly suggest that in Cu(2+) and Cr...

Cyanobacteria combine the photosynthetic and respiratory electron transport in one membrane system, the thylakoid membrane. This feature requires an elaborate regulation mechanism to maintain a certain redox status of the electron transport chain, hence allowing proper photosynthetic and respiratory energy metabolism. In this context, metabolic adaptations, as seen in the light-to-dark and dark...