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In this study, an autogenous N-doped biochar derived from Chlorella (CVAC) was prepared with NaOH as activator at 800 °C. The surface structural properties of CVAC and the adsorption performance of CVAC on tetracycline (TC) under different adsorption variables were analyzed and investigated using different characterization methods. The results showed that the specific surface area of CVAC was 491.16 m 2  g -1 and the adsorption process was in accordance with Freundlich model and pseudo-second-order kinetic model. The maximum adsorption capacity of TC was 310.696 mg g -1 at pH 9 and 50 °C, and it was mainly physical adsorption. Furthermore, the cyclic adsorption-desorption behavior of CVAC using ethanol as eluent was evaluated and the feasibility of its long-term application was explored. CVAC also showed good cyclic performance. The variation of ΔG° and ΔH° confirmed that the adsorption of TC by CVAC was a spontaneous heat absorption process., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Shuang Wang reports financial support was provided by National Natural Science Foundation of China., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Marine organisms need to adapt to improve organismal fitness under ocean acidification (OA). Recent studies have shown that marine calcifiers can achieve acclimation by stimulating calcium binding/signaling pathways. Here, a CaM-like gene (CgCaLP-2) from oyster Crassostrea gigas which typically responded to long-term CO 2 exposure (two months) rather than short-term exposure (one week) was characterized. The cloned cDNA was 678 bp and was shorter than the retrieved sequence from NCBI (1125 bp). The two sequences, designated as CgCaLP-2-v1 and CgCaLP-2-v2, were demonstrated to be different splice variants by the genome sequence analysis. Western blotting analysis revealed two bands of 23 kD and 43 kD in mantle and hemocytes, corresponding to predicted molecular weight of CgCaLP-2-v1 and CgCaLP-2-v2, respectively. The isoform CgCaLP-2-v1 (the 23 kD band) was highly stimulated in response to long-term CO 2 exposure (42-day and 56-day treatment) in hemocytes and mantle tissue. The fluorescence signal of CgCaLP-2 in mantle and hemocytes became more intensive after long-term CO 2 exposure. Besides, in hemocytes, CgCaLP-2 presented a higher localization on the nuclear membrane after long-term CO 2 exposure (56 d). The target gene network of CgCaLP-2 was predicted, and a transcription factor (TF) gene annotated as Homeobox protein SIX4 (CgSIX4) showed a similar expressive trend to CgCaLP-2 during CO 2 exposure. Suppression of CgCaLP-2 via RNA interference significantly reduced the mRNA expression of CgSIX4. The results suggested that CgCaLP-2 might mediate the Ca 2+ -CaLP-TF signal transduction pathway under long-term CO 2 exposure. This study serves as an example to reveal that alternative splicing is an important mechanism for generation multiple protein isoforms and thus shape the plastic responses under CO 2 exposure, providing new insight into the potential acclimation ability of marine calcifiers to future OA., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Composite functional materials offer promising opportunities for the development of tailored adsorbents with enhanced bioremediation potential towards toxic, carcinogenic endocrine disrupters such as Bisphenol A (BPA). Copyrolysis of microalga Chlorella sp. (CH) alkali lignin (L) with K 2 CO 3 impregnation yielded a carbon-based composite (CHL-AC) with a micro-mesoporous structure of 0.643 cm 3 /g, surface area of 1414 m 2 /g, and BPA adsorption capacity of Q max 316.858 mg/g. Enhanced BPA removal efficiency indicated a positive synergistic effect upon a combination of L and CH, resulting in a 73.24 % removal efficiency compared with the individual carbon components of 52.33 % for L-AC and 67.35 % for CH-AC. The kinetics and equilibrium results were described well by the pseudo second-order kinetic model and Freundlich isotherm, respectively. This paper elucidates the blending of microalgae and lignin into high-value carbon composite material, CHL-AC, with immense potential for the treatment of BPA-contaminated waters to contribute to Goal 6 (clean water and sanitation)., Competing Interests: Declaration of competing interest We declare no conflicts of interest associated with submission., (Copyright © 2022. Published by Elsevier B.V.)

Activated carbon (ENAC) was prepared by NaOH activation, using macroalgae (Enteromorpha clathrate) as raw material. The prepared activated carbon has a large surface area (1238.491 m 2 g -1 ) and its total pore volume and average pore size are 0.6823 cm 3 g -1 and 2.2038 nm, respectively. The ENAC was characterized by SEM, FTIR, BET and XPS. The effects of contact time (0-960 min), initial tetracycline (TC) concentration (50-500 mg L -1 ), temperature (30-50 °C) and initial pH (2-11) on TC adsorption were evaluated. The adsorption isotherm and adsorption kinetics were discussed. Results showed that the adsorption isotherm was the Langmuir model, and the adsorption process can be described by the pseudo-second-order model. The N 2 adsorption-desorption isotherm was type IV, indicating that the activated carbon had mesoporous structure. Thermodynamic analysis showed that the adsorption process was endothermic and spontaneous. The maximum adsorption capacity of TC was 381.584 mg g -1 . Density functional theory (DFT) was used to simulate and analyze the adsorption process, and the influence of different types of N on the adsorption was expounded. The results showed that there are electrostatic interactions, π-π interactions and hydrogen bonding between the adsorbent and TC. These results indicated that the prepared ENAC had a great application prospect in the removal of antibiotics from aqueous solution., (Copyright © 2021 Elsevier B.V. All rights reserved.)

A FeCl 3 -activated seaweed carbon/MCM-41/alginate hydrogel composite (ECAC/MCM-41/ ALG) cross-linked with calcium chloride (2% CaCl 2 ) was synthesized for the biosorption of bisphenol A (BPA) plasticizer and basic blue (BB) dye. Biosorption uptakes of BPA and BB were performed in a batch mode with varying solution pH from 3 to 11, initial sorbate concentration from 25 to 300 mg/L, reaction time from 0 to 10 h, and biosorption temperature from 30 to 50 °C. The maximum BPA and BB uptake mechanisms were fast, which occurred within contact times of 1 and 2 h with monolayer coverage capacities of 222.32 and 190.11 mg/g at 50 °C, respectively. Cyclic biosorption/desorption behavior was evaluated via an ethanol elution to evaluate the feasibility of the ECAC/MCM-41/ALG for long-term application. Results revealed the biosorption renewability for five cycles up to 80% of the newly synthesized hydrogel composite for the purification of industrial wastewater laden with emerging contaminants., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

A bench-scale constructed wetland combined with microbial electrochemical technology (MET-CW) was run for 400days with groundwater contaminated with benzene, methyl-tert-butyl ether (MTBE), and ammonium (NH4(+)). Four vertically stacked anode modules were embedded into a sand bed and connected with a stainless steel cathode placed in an open water pond. In the zone of presence of anode modules, significantly more benzene and MTBE were removed in the MET-CW compared to the control CW without MET in the first 150 operation days. Benzene was identified as primary electron donor at the anode. Benzene removal and current densities were linearly correlated, implying the potential of the system for electrochemically monitoring benzene biodegradation. Compound-specific isotope analysis (CSIA) indicated that benzene was initially activated by monohydroxylation forming intermediates which were subsequently oxidized accompanied by extracellular electron transfer, leading to current production. NH4(+) removal was not stimulated by MET., (Copyright © 2015 Elsevier Ltd. All rights reserved.)