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A mesoporous crosslinked chitosan-activated clinoptilolite biocomposite (CS-GA/ACP) was prepared with chitosan (CS) as the substrate and glutaraldehyde (GA) as the crosslinking agent. Structural analysis of the CS-GA/ACP composite beads was performed using FTIR, SEM, and BET techniques. The adsorption properties of the CS-GA/ACP for Congo red (CR) and methylene blue (MB) removal were examined using a batch method. The effects of CS loading, CS-GA/ACP dosages (0.005-0.25 g), pH values (3-11), initial concentrations (30-300 mg/L), contact time (5-120 min), ionic strength, and temperatures (25-65 ℃) on the adsorption of CR and MB on the CS-GA/ACP composite beads were investigated. The pseudo-second-order kinetics could better describe the adsorption process than the pseudo-first-order kinetics, and the Langmuir isotherms model agreed well with the experimental data. The maximum adsorption capacities of the CS-GA/ACP for CR and MB were 180.59 mg/g and 143.67 mg/g at 25 ℃, respectively. The proposed mechanism studies showed that the possible interaction between the adsorbent and dye molecules were Yoshida H-bonding, dipole-dipole H-bonding, electrostatic interaction and n-π interaction. The CS-GA/ACP can be recycled to remove dyes without significant loss of efficacy, and the adsorption of dyes on the CS-GA/ACP is spontaneous endothermic adsorption. Overall, the CS-GA/ACP showed an excellent performance for dyes removal in aqueous solution and could be a practical candidate for industrial applications., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Ocean acidification (OA) resulting from increasing atmospheric CO 2 strongly influences marine ecosystems, particularly in the polar ocean due to greater CO 2 solubility. Here, we grew the Antarctic sea ice diatom Nitzschia sp. ICE-H in a semicontinuous culture under low (~400ppm) and high (1000ppm) CO 2 levels. Elevated CO 2 resulted in a stimulated physiological response including increased growth rates, chlorophyll a contents, and nitrogen and phosphorus uptake rates. Furthermore, high CO 2 enhanced cellular particulate organic carbon production rates, indicating a greater shift from inorganic to organic carbon. However, the cultures grown in high CO 2 conditions exhibited a decrease in both extracellular and intracellular carbonic anhydrase activity, suggesting that the carbon concentrating mechanisms of Nitzschia sp. ICE-H may be suppressed by elevated CO 2 . Our results revealed that OA would be beneficial to the survival of this sea ice diatom strain, with broad implications for global carbon cycles in the future ocean., (Copyright © 2017. Published by Elsevier Ltd.)

A cDNA (GenBank ID: GU395492) encoding cytosolic glutathione reductase (named ICE-LGR) in Antarctic microalgae Chlamydomonas sp. ICE-L was successfully cloned by RT-PCR and rapid amplification of cDNA ends technique (RACE). The expression patterns of ICE-LGR under different salinity stresses were determined by real-time PCR. ICE-LGR cDNA has 1913 bp nucleotides with an open reading frame (ORF) of 1458 bp, encoding 485 amino acid residues. The deduced amino acid sequence shows 79% homology with glutathione reductase (GR) of Chlamydomonas reinhardtii. Activity assessment and mRNA expression analysis results showed that activity and expression level of GR in ICE-L cells were up-regulated under either high or low salinity. Together, our results revealed that ICE-LGR might play an important role in Antarctic ice algae Chlamydomonas sp. ICE-L acclimatizing to polar high salinity environment as well as low salinity. These results provide us valuable information on further investigating the molecular mechanism of ICE-LGR., (Copyright © 2011 Elsevier B.V. All rights reserved.)