Influence of a Combination of Flocculants on Harvesting of 
                            Chaetoceros gracilis
                        
 Marine Microalgae

We examined uptake of tri-n-butyltin (TBT) by three genera of marine microalgae and one genus of cyanobacterium. There was a linear relationship between external concentrations of TBT and cell burdens in the microalgae Nannochloris sp., Chaetoceros gracilis, and the cyanobacterium Synechococcus sp. (PR-6). The relationship between external TBT concentrations and cell TBT burdens was distinctly nonlinear for Isochrysis galbana. Competitive binding experiments showed a decrease of approximately 88% of the total bound radiolabeled TBT to I. galbana in the presence of a 200-fold excess of unlabeled TBT. No significant decrease of bound TBT was observed for Nannochloris sp. These studies demonstrate that either partitioning or binding may control bioaccumulation of TBT by marine phytoplankton.

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Isoprostanoid Profiling of Marine Microalgae

Biomolecules ◽

10.3390/biom10071073 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1073

Author(s):

Claire Vigor ◽

Camille Oger ◽

Guillaume Reversat ◽

Amandine Rocher ◽

Bingqing Zhou ◽

...

Keyword(s):

Mass Spectrometry ◽

Fatty Acids ◽

Polyunsaturated Fatty Acids ◽

Phaeodactylum Tricornutum ◽

Marine Microalgae ◽

Copper Stress ◽

Bioactive Metabolites ◽

Chaetoceros Gracilis ◽

Oily Fish ◽

Mass Spectrometry Mass Spectrometry

Algae result from a complex evolutionary history that shapes their metabolic network. For example, these organisms can synthesize different polyunsaturated fatty acids, such as those found in land plants and oily fish. Due to the presence of numerous double-bonds, such molecules can be oxidized nonenzymatically, and this results in the biosynthesis of high-value bioactive metabolites named isoprostanoids. So far, there have been only a few studies reporting isoprostanoid productions in algae. To fill this gap, the current investigation aimed at profiling isoprostanoids by liquid chromatography -mass spectrometry/mass spectrometry (LC-MS/MS) in four marine microalgae. A good correlation was observed between the most abundant polyunsaturated fatty acids (PUFAs) produced by the investigated microalgal species and their isoprostanoid profiles. No significant variations in the content of oxidized derivatives were observed for Rhodomonas salina and Chaetoceros gracilis under copper stress, whereas increases in the production of C18-, C20- and C22-derived isoprostanoids were monitored in Tisochrysis lutea and Phaeodactylum tricornutum. In the presence of hydrogen peroxide, no significant changes were observed for C. gracilis and for T. lutea, while variations were monitored for the other two algae. This study paves the way to further studying the physiological roles of isoprostanoids in marine microalgae and exploring these organisms as bioresources for isoprostanoid production.

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A photobioreactor using Nannochloropsis oculata marine microalgae for removal of polycyclic aromatic hydrocarbons and sorption of metals in produced water

Chemosphere ◽

10.1016/j.chemosphere.2021.130775 ◽

2021 ◽

pp. 130775

Author(s):

Isadora Machado Marques ◽

Adna Caroline Vale Oliveira ◽

Olivia Maria Cordeiro de Oliveira ◽

Emerson Andrade Sales ◽

Ícaro Thiago Andrade Moreira

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Aromatic Hydrocarbons ◽

Produced Water ◽

Nannochloropsis Oculata ◽

Marine Microalgae ◽

Polycyclic Aromatic

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Removal of Pharmaceutical Micropollutants with Integrated Biochar and Marine Microalgae

Microorganisms ◽

10.3390/microorganisms9010004 ◽

2020 ◽

Vol 9 (1) ◽

pp. 4

Author(s):

Amin Mojiri ◽

Maedeh Baharlooeian ◽

Reza Andasht Kazeroon ◽

Hossein Farraji ◽

Ziyang Lou

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Response Surface Methodology ◽

Cell Viability ◽

Response Surface ◽

Contact Time ◽

Marine Microalgae ◽

Chaetoceros Muelleri ◽

Mean Squared Errors ◽

High Concentrations

Using microalgae to remove pharmaceuticals and personal care products (PPCPs) micropollutants (MPs) have attracted considerable interest. However, high concentrations of persistent PPCPs can reduce the performance of microalgae in remediating PPCPs. Three persistent PPCPs, namely, carbamazepine (CBZ), sulfamethazine (SMT) and tramadol (TRA), were treated with a combination of Chaetoceros muelleri and biochar in a photobioreactor during this study. Two reactors were run. The first reactor comprised Chaetoceros muelleri, as the control, and the second reactor comprised Chaetoceros muelleri and biochar. The second reactor showed a better performance in removing PPCPs. Through the response surface methodology, 68.9% (0.330 mg L−1) of CBZ, 64.8% (0.311 mg L−1) of SMT and 69.3% (0.332 mg L−1) of TRA were removed at the initial concentrations of MPs (0.48 mg L−1) and contact time of 8.1 days. An artificial neural network was used in optimising elimination efficiency for each MP. The rational mean squared errors and high R2 values showed that the removal of PPCPs was optimised. Moreover, the effects of PPCPs concentration (0–100 mg L−1) on Chaetoceros muelleri were studied. Low PPCP concentrations (<40 mg L−1) increased the amounts of chlorophyll and proteins in the microalgae. However, cell viability, chlorophyll and protein contents dramatically decreased with increasing PPCPs concentrations (>40 mg L−1).

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