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Shellfish and seaweed, the primary mariculture species in China, generate significant amounts of dissolved organic matter (DOM) during growth. This production significantly influences the carbon cycle in the marine environment. In the present study, we evaluated the DOM changes during growth in both seawater and sediments in Nan'ao, Guangdong Province, southern China. The results showed that both shellfish and seaweed growth increased organic carbon content in seawater and sediments. DOM and water-extractable organic matter in the seaweed cultivation area exhibited greater aromaticity and hydrophobicity, indicating that seaweed-produced organic matter is more difficult to decompose and resistant to consumption. This implies a potential to expand the refractory dissolved organic carbon (RDOC) pool in the marine environment. We also estimated carbon removal and carbon sequestration by shellfish and seaweed culture in Guangdong Province from 2012 to 2021. Average carbon removal by shellfish cultivation is at 227.81 Gg C yr -1 , and the release of carbon is at 205.71 Gg C yr -1 . Carbon removal by seaweed cultivation is at 22.95 Gg C yr -1 with carbon sequestration of 11.89 Gg C yr -1 . Compared with shellfish, seaweed has a large carbon sequestration potential. The integrated aquaculture of shellfish and seaweed in adjacent areas, given the environmental and socioeconomic benefits of absorbing nitrogen and phosphorus nutrients, mitigating eutrophication, and ocean acidification, is advisable for coastal developing countries to promote shellfish-seaweed farming., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The spatial layout of the air quality monitoring network (AQMN) is crucial for objective, accurate, and comprehensive air quality assessment. The current technical standard specified the minimum quantity requirements for air quality monitoring sites, but there were no standards to specify the spatial of monitoring sites. This study proposed a novel framework to evaluate and optimize the spatial layout of AQMN. First, this study proposed three indicators to evaluate the performance of the current AQMN. They were monitoring area repetition rate, population coverage rate, and correlations. The assessment of AQMN in Beijing-Tianjin-Hebei and surroundings areas (BTHs) showed the overall monitoring area repetition rate and population coverage rate was 81.07 % and 35.5 %, respectively, which means the current AQMN in BTHs has very high monitoring repeatability and limited population coverage. Secondly, a large-scale linear programming model was built to optimize the spatial layout and determine the spatial location of 279 newly added monitoring sites in BTHs according to the Environmental Monitoring 14th Five-Year Plan of China. The optimization results showed that the optimized AQMN covered 97 million additional people, and the population coverage rate increased to 49.5 %. The proposed framework provided a valuable tool to evaluate and optimize AQMN and could be a potential solution for developing new technical standards of AQMN., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Seaweeds, as marine photosynthetic organisms, are harvested by humans from the wild or through cultivation for various production purposes and to provide a range of marine ecosystem services, including nutrient removal, oxygen production, and carbon sequestration. The potential use of cultivated seaweed in mitigating carbon dioxide (CO 2 ) has been extensively proposed in conjunction with commercial seaweed production worldwide. This study aims to assess the annual potential and benefits of cultivated seaweed in reducing and fixing anthropogenic CO 2 . Over the past two decades (2000-2019), global seaweed production has seen significant growth. The total output of cultivated seaweed reached 407.4 × 10 7 tons (t), with coastal mariculture removing 4.26 × 10 7  t of carbon annually and wild capture removing 2.24 × 10 6  t. The recalcitrant dissolved organic carbon (RDOC, 549.88-621.60 × 10 4  t) plays a significant role in the carbon sinks of seaweed cultivation. The substantial benefits of carbon sink resulting from the formation of RDOC from seaweed make up a considerable proportion in the calculation of carbon sequestration and sink enhancement benefits in large-scale seaweed cultivation. The sizable carbon sink base of seaweed cultivation (8631.90-9567.37 × 10 4  t) results in significant carbon fixation benefits. The total economic value of carbon sequestration and oxygen production was estimated at $70.36 ± 1.52 billion, with an annual average benefit of $3.52 ± 1.70 billion. Increasing the area and yield available for cultivated seaweed has the potential to enhance biomass production, carbon accumulation, and CO 2 drawdown. It is crucial to emphasize the need for improved communication regarding the essential criteria for the feasibility of CO 2 removal (CDR), with a focus on conducting life cycle assessments (LCA) when utilizing marine processes in the present and future work. The sustainable development of the seaweed cultivation industry not only ensures that Asian-Pacific countries remain leaders in this field but also provides an effective yet overlooked solution to excessive CO 2 emissions worldwide., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Seaweed debris is susceptible to being buried in sediments due to natural environmental changes and human activities. So far, the effect of buried seaweeds on the environment and its decomposition mechanism remains unclear. This study simulated the decomposition of seaweed Gracilariopsis lemaneiformis for 180 days with different burial depths (0 cm and 10 cm) and burial weights (10 g and 20 g). Our findings revealed that compared with Gracilariopsis decomposition on the sediment surface, the seaweed buried in sediment slowed down the release of N, P, and dissolved organic carbon (DOC) by enhancing the activity of diverse anaerobic microbes (i.e. Draconibacterium, Desulfuromusa, Sediminispirochaeta), which were associated with organic matter decomposition. The enhanced burial quantity of Gracilariopsis resulted in a 3.28 % increase in sediment OC and enriched the humification degree of DOC in seawater. These results highlight the role of seaweed burial in enhancing OC sequestration in marine environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Our previous research revealed the apoptosis-inhibiting effect of lncRNA FAM230B in gastric cancer (GC). While its role on ferroptosis of GC remain unexplored. In this study, the m6A level and RNA stability regulation of METTL3 on FAM230B was detected by m6A quantification, stability assays, MeRIP, and their interaction was confirmed by RIP, and RNA pull-down assays. The level of ferroptosis was detected by flow cytometry, MDA and GSH level assessments, and electron microscopy. Gene expression was detected by quantitative real-time PCR, western blot, and immunofluorescence. The miR-27a-5p and BTF3 interaction was predicted with TargetScan and confirmed by dual-luciferase assay. Here, elevated levels of METTL3 and FAM230B were observed in GC tissues and cell lines. METTL3 was confirmed to bind with FAM230B RNA. Furthermore, silencing METTL3 reduced FAM230B m6A levels and stability, leading to decreased FAM230B and increased miR-27a-5p expressions. FAM230B knockdown favored ferroptosis and increased BTF3 expression, while its overexpression mitigated erastin-induced ferroptosis in GC cells. Additionally, BTF3 overexpression was found to negate miR-27a-5p's ferroptosis-promoting effects in GC cells. Collectively, our study demonstrates that the m6A modification of FAM230B by METTL3 plays a crucial role in promoting GC progression by reducing ferroptosis, through the modulation of the miR-27a-5p/BTF3 axis., Competing Interests: Declaration of competing interest The authors declared that they have no conflict of interest regarding to this research., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Consumed VOCs are the compounds that have reacted to form ozone and secondary organic aerosol (SOA) in the atmosphere. An approach that can apportion the contributions of primary sources and reactions to the consumed VOCs was developed in this study and applied to hourly VOCs data from June to August 2022 measured in Shijiazhuang, China. The results showed that petrochemical industries (36.9 % and 51.7 %) and oxidation formation (20.6 % and 35.6 %) provided the largest contributions to consumed VOCs and OVOCs during the study period, whereas natural gas (5.0 % and 7.6 %) and the mixed source of liquefied petroleum gas and solvent use (3.1 % and 4.2 %) had the relatively low contributions. Compared to the non-O 3 pollution (NOP) period, the contributions of oxidation formation, petrochemical industries, and the mixed source of gas evaporation and vehicle emissions to the consumed VOCs during the O 3 pollution (OP) period increased by 2.8, 3.8, and 9.3 times, respectively. The differences in contributions of liquified petroleum gas and solvent use, natural gas, and combustion sources to consumed VOCs between OP and NOP periods were relatively small. Transport of petrochemical industries emissions from the southeast to the study site was the primary consumed pathway for VOCs emitted from petrochemical industries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cultivation of the seaweed, Gracilariopsis lemaneiformis, supports environmental bioremediation and the aquaculture economy in coastal ecosystems, and microorganisms play important roles during the cultivation process. In this study, we aimed to understand the response of bacterial communities through a full cultivation cycle of G. lemaneiformis. We analyzed the bacterial communities using 16S rRNA gene amplicon sequencing and defined the environmental factors of 144 water samples from the Nan'ao Island, South China Sea. Community diversity, keystone species and ecological networks of bacterial communities shifted markedly in the cultivation zone largely due to changes in the environmental factors, seaweed biomass and cultivation stages. The bacterial communities at the seaweed zone have lower species richness, more seaweed-associated taxa and simpler but more stable co-occurrence networks compared to the control zone. Persistent microbial groups such as Aquimarina, Formosa, Glaciecola and Marinobacter exhibited a strong association with seaweed during the growth and maturity stages. We describe a conceptual model to summarize the changes in the bacterial community composition, its diversity and the ecological networks in seaweed cultivation zone. Overall, this study provides new perspectives on the dynamic interaction of seaweed cultivation, bacterial communities and environment factors and their potential ecosystem services as observed in the example of the G. lemaneiformis cultivation ecosystem., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

In large-scale seaweed farming, an understanding of the decomposition process plays a pivotal role in optimizing cultivation practices by considering the influence of the bacterial community. Therefore, we assessed the bacterial community structure and its influence on environmental factors during Gracilaria lemaneiformis decomposition, utilizing both microcosms and in-situ simulations. The decomposition rates in the microcosms and in situ simulations reached 79 % within 180 days and 81 % within 50 days, respectively In the microcosms, the dissolved oxygen content decreased from 5.3 to 0.4 mg/L, while the concentrations of total organic carbon, nitrogen, and phosphorus in the water increased by 165 %, 1636 %, and 2360 %, respectively. The common dominant bacteria included Proteobacteria, Planctomycetes, Firmicutes, Bacteroidetes, and Spirochaetae. Planctomycetes and Firmicutes were positively correlated with the total organic carbon, nitrogen, and phosphorus concentrations. Planctomycetes species played significant roles during the decomposition process. The overall findings of this study could inform more sustainable seaweed cultivation practices., Competing Interests: Declaration of competing interest The authors declare that this study was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest., (Copyright © 2023. Published by Elsevier Ltd.)

Gracilaria bioremediates heavy metals (Cd, Cr, Pb, Ni, Cu, Zn, Fe, and Mn) and improves water quality in mariculture zones. However, Gracilaria litter produced during the growth and harvest process has become a critical bottleneck problem that limits the sustainable development of the Gracilaria cultivation industry. Experiments of decaying dried (dead) and frozen fresh (falling and dying) G. lemaneiformis and G. lichenosdies were carried out using the litterbag technique under laboratory-controlled and in situ conditions. The results showed that decay rates (k), decomposed time in 50 % (t50) and in 95 % (t95) varied between dried and frozen fresh Gracilaria and were different between G. lemaneiformis and G. lichenosdies. All Gracilaria samples showed an 80 %-90 % weight loss in 15-45 d. The variation in MAIs (accumulation index of metals) between the dried and frozen fresh Gracilaria litters differed significantly and provided evidence that metals could be imported or exported from litter to the environment. Based on our estimates from the 15-45 d experiment, the decay of Gracilaria can release and adsorb heavy metals. The enrichment of Fe, Pb, and Mn was more significant than the release, but the release of Cr, Zn, Cd, Pb, Cu, and Ni was more significant than the enrichment. Heavy metals in Gracilaria litters were accumulated and released simultaneously during decay. The present study simulated and underscores that Gracilaria cultivation intensely influences heavy metals recycled in marine environments It provides a theoretical basis for seaweed management for the sustainable development of the seaweed industry in the mariculture zone., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The spatio-seasonal variation, bioaccumulation and potential ecological risk of four metals (Co, Ni, Cu and Zn) in the multi-media of the Pearl River Estuary (PRE) were assessed. The degree of contamination and ecological risk of the four metals followed this pattern: Cu > Zn > Ni > Co, upstream > downstream, wet season > dry season. There were non-linear and linear correlations for Co, linear and non-linear correlations for Ni, and non-linear and no correlation for both Cu and Zn, between metals in bottom water or bioavailable concentrations in sediment and fish muscle. Co and Ni showed lightly polluted levels; Cu and Zn showed heavily polluted levels. This study demonstrates a tendency of cross-accumulation in fish of these four transition metals within specific habitats of the PRE., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

Seaweeds are important primary producers and bioremediation materials, but its litter produced during growth and harvest is one of the restrictions to the sustainable development of seaweed cultivation. In this study, we conducted field investigation and indoor experiments to analyze the bioaccumulation and release of metals in Gracilaria lemaneiformis during the growth and decaying. The investigation revealed the 3.5 × 10 5  t (wet weight) G. lemaneiformis from a 1500 ha cultivation area bioaccumulated 1925-2353 kg Zn, 233.5-251 kg Cu, 70.5-80.5 kg Pb and 25.5-47 kg Cd, indicating that G. lemaneiformis is a good metals remover. The growth and decaying period of G. lemaneiformis releases, absorbs or adsorbs metals. It has the function of a "heavy metal pool", simultaneously accumulate and release metals. G. lemaneiformis has a strong influence on heavy metals cycling in the seaweed cultivation ecosystem and provides a very good sample for biogeochemistry study for the globally seaweed sustainable development., (Copyright © 2021. Published by Elsevier Ltd.)

Seaweed is an inherently important entity in marine ecosystems. It is not only consumed by aquatic animals but also improves environmental quality in the mariculture. Seaweed is also part of the diet of human beings. The purpose of the present study was to evaluate the antagonism of selenium (Se)-enriched Gracilaria lemaneiformis against heavy metals, specifically, the potential of dietary Se-enriched Gracilaria to protect against heavy metal toxicity in rabbitfish (Siganus oramin). Growth rate, heavy metal (Se, Cd, Pb, Cu, Zn and Cr) concentrations, malondialdehyde (MDA), metallothionein (MT), and the activity of the antioxidants, glutathione peroxidase (GPX), catalase (CAT) and superoxide dismutase (SOD) were all assessed. The results showed that the total organic and inorganic Se concentration for the 250 mg L -1 Se-enriched Gracilaria was significantly higher than those of the 50 and 10 mg L -1 treatments after 3 days of enrichment. The mean total Se concentrations in Gracilaria were 42.5 μg g -1 in the 250 mg L -1 treatment, 13.5 μg g -1 in the 50 mg L -1 treatment and 2.5 μg g -1 in the 10 mg L -1 treatment, respectively. Organic Se accounts for 80-82% of total Se in Se-enriched Gracilaria. The Se concentration of rabbitfish fed Se-enriched Gracilaria was significantly higher than control. Furthermore, Se increased Cu and Zn absorption, and enhanced MT generation, and improved GPX, CAT, and SOD antioxidant activity, and decreased MDA concentrations and lipid peroxidation levels, all antagonistic to Cd, Pb and Cr. The effects of Se-enriched Gracilaria on waterborne Cd, Pb and Cr-induced toxicity occurred via both enzymatic and non-enzymatic antioxidative mechanisms in rabbitfish. Selenium had synergistic effects on Zn and Cu in rabbitfish. For the 50 mg L -1 Se-enriched Gracilaria treatment, the Se, Cu, Zn, and antagonistic Cd, Pb, Cr, and the antioxidant enzymes CAT, SOD, GPX activities, and MT concentrations in rabbitfish were higher than that with the 250 mg L -1 and 10 mg L -1 Se-enriched Gracilaria treatments. The 50 mg L -1 Se treatment of Gracilaria was deemed to be the optimum concentration to promote growth of rabbitfish. Therefore, the obtained results suggest Se-enriched Gracilaria can antagonize heavy metal toxicity, and is an advisable Se supplement to improve the edible safety of cultured animals., (Copyright © 2020 Elsevier Inc. All rights reserved.)

To understand the heterogeneous behavior of oil-particle aggregates (OPAs) in the riverine environment as well as the uncertainties caused by the coupling effects between their stochastic formation and transportation processes, this study employed the coagulation conceptual formula and random-walk particle tracking model. Through careful inspection using the classic Rouse-Vanoni diagram and existing laboratory observations, a vertical diffusivity scheme and the packing coefficient for an oil-sediment interaction model were determined. The density variations and deposition patterns of hypothetically fully developed OPAs as well as the impact of oil-sediment interactions on the longitudinal distribution of deposited OPAs were then investigated. The results indicate that the formation process of OPAs has a significant effect on their longitudinal deposition. The range of potentially trapped OPAs varied from several to hundreds of times the range of cases that exclude oil-sediment interactions. The deposition diagram proposed in this study visualizes the relationship between the configuration and deposition pattern of OPAs and can assist in determining the most unfavorable scenarios for oil-spill countermeasures. Further refinement and calibration of the model are necessary in the future to provide guidelines for oil spill responses and recovery in riverine environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Prymnesium (Haptophyta) species form toxic blooms throughout the world resulting in large fish-kills and economic losses. A culture of Prymnesium parvum JX12 was isolated and established from the Pearl River Estuary of China. The toxic characteristics of JX12 to aquatic animals were investigated, considering the effects of temperature, salinity, and nutrients. Cultures of JX12 exhibited significant lethal toxicity to the fish, Mugil sp., M. soiuy, M. cephalus, Ctenogobius sp. and Chrysiptera parasema, and the brine shrimp, Artemia salina, but no significant effects on the shellfish Ruditapes variegatus and the shrimp Penacus orientalis. The toxicity of JX12 to A. salina increased with growth of the culture. The decline phase displayed the strongest potency, followed by the stationary phase, exponential phase and lag phase. Also, there was a significant difference in toxicity among culture fractions of JX12 compared to whole-cell culture. For example, the toxicity of a cell-free culture filtrate on brine shrimp was reduced by 50% by the end of the experiment, while the sonicated and re-suspended cultures caused near 100% mortality. The toxicity of JX12 was also regulated by environmental factors such as temperature, salinity and nutrients. The strongest toxicities were at moderate water temperature (20-25 °C) and salinity (35 psu). The toxicity was reduced significantly at higher or lower temperatures and salinities. Furthermore, the toxicity of JX12 was greatly enhanced when ambient nutrients were deficient. Due to the potent toxicity of JX12 to multiple aquatic animals, especially fish and zooplankton, this species threatens the food web and trophic dynamics of coastal ecosystems. This study suggested that the ability to produce and release toxin(s) is an effective competition strategy for P. parvum to suppress predators and sympatric competitors and thus form blooms., Competing Interests: Declaration of Competing Interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Submerged macrophytes are widely distributed primary producer that play important roles in maintaining healthy aquatic ecosystems. Generally, the relationships between macrophytes and environmental factors are complicated, so nonlinear nonparametric models with relatively flexible structures are optimal for macrophyte habitat simulation. In this study, generalized additive model (GAM) was used to evaluate the response of the submerged macrophytes biomass to water environmental factors in the Baiyangdian Lake. Forward stepwise method was used to implement model optimization. Likelihood ratio test was used to determine whether adding a variable enhances the model performance. Four individual variables (water depth, transparency, total nitrogen, and total phosphorus) and two interaction terms (water depth × transparency and water depth × total phosphorus) were included in the optimal GAM. The optimal model explained 70.5% of the biomass variation with a relatively low residual deviance value (22.40). There was a significant correlation between the measured and predicted data (R 2  = 0.716, p = 0.0004). The response lines generated by the model indicated that macrophyte biomass had a positive correlation with transparency but negative correlations with total nitrogen and nitrite nitrogen in water. The response patterns of macrophyte biomass to water depth and total phosphorus were unimodal. The biomass reached the maximum value when the water depth was about 2.1 m and the total phosphorus concentration was 0.07 mg/L. Water depth and transparency, which affect light availability, are critical physical variables affecting the conditions associated with the submerged macrophytes, and excess nitrite and phosphorus limiting macrophyte biomass., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Seaweed Gracilaria lemaneiformis is the main dietary source of the abalone mariculture industry in China. In this study, we examined the protection of selenium (Se)-enriched G. lemaneiformis against cadmium (Cd) toxicity in the abalone, Haliotis discus hannai, using various indices including metal concentration (Se and Cd), growth rate, GPx enzymatic antioxidants, and metallothionein (MT) concentration over a period of 28 days of exposure. The growth rates and Se contents increased significantly in abalones fed with Se-enriched G. lemaneiformis, while the toxicity of Cd was reduced. Seven to 12 days Cd exposure to the Se-enriched G. lemaneiformis not only affected GPx activity but the MT levels fluctuated irregularly. MT concentrations increased after 3 days exposure and then gradually decreased to the control level after Day 7. There were statistically significant positive correlations between MT levels, GPx activity and Se concentrations, and negative relationships between MT levels, GPx activity and Cd levels in abalones. These findings suggest that Se-enriched Gracilaria protects abalone against Cd toxicity. The possible mechanism is the induction of MT with a concomitant increased capacity of GPx enzymatic antioxidants., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Seaweeds take up elements directly from seawater and have been widely employed in coastal field studies of trace element contamination. In our study, the contents of the elements, K, P, Ca, Mg, Na, Fe, Mn, Zn, Cu, B, Cd, Cr, Ni, Pb and Se, were determined from eight dominant seaweeds and the seawater from Shen'ao bay, Nan'ao Island. The levels of Cr, Ni, Mn, Zn, Cd and Pb in the seaweeds showed similar contents. Moreover, B and Se levels were in a similar pattern as those reported from other coastal areas. Rhodophyta showed higher contents and bioconcentration factors (BCF) of B than Chlorophyta or Phaeophyta. Chlorophyta had greater contents of Fe, Ni and Pb than either Rhodophyta or Phaeophyta. U. fasciata is a good biomonitor and strong accumulator of Ni and Pb, G. lemaneiformis of Zn, Cr and Se, and S. fusiforme of Cu and Cd. Our data, along with those from other investigators, can help interpret the biomonitoring data and the design of biomonitoring programs for the protection and management of coastal environments., (Copyright © 2018. Published by Elsevier B.V.)

Seaweed cultivation not only provides economy benefits, but also remediates the environment contaminated by mariculture of animals (e.g., fish, shrimps). However, the response of microbial communities to seaweed cultivation is poorly understood. In this study, we analyzed the diversity, composition, and structure of water and sediment microbial communities at a seaweed, Gracilaria lemaneiformis, cultivation zone and a control zone near Nan'ao Island, South China Sea by MiSeq sequencing of 16S rRNA gene amplicons. We found that large-scale cultivation of G. lemaneiformis increased dissolved oxygen (DO) and pH but decreased inorganic nutrients, possibly due to nutrient uptake, photosynthesis and other physiological processes of G. lemaneiformis. These environmental changes significantly (adonis, P<0.05) shifted the microbial community composition and structure of both water column and sediment samples in the G. lemaneiformis cultivation zone, compared to the control zone. Also, certain microbial taxa associated with seaweed, such as Arenibacter, Croceitalea, Glaciecola, Leucothrix and Maribacter were enriched at the cultivation zone. In addition, we have proposed a conceptual model to summarize the results in this study and guide future studies on relationships among seaweed processes, microbial communities and their environments. Thus, this study not only provides new insights into our understanding the effect of G. lemaneiformis cultivation on microbial communities, but also guides future studies on coastal ecosystems., (Copyright © 2017. Published by Elsevier B.V.)

Mitophagy is the selective degradation of mitochondria by autophagy, which is an important mitochondrial quality and quantity control process. During Drosophila metamorphosis, the degradation of midgut involves a large change in length and organization, which is mediated by autophagy. Here we noticed a cell-type specific mitochondrial clearance process that occurs in enterocytes (ECs), while most mitochondria remain in intestinal stem cells (ISCs) during metamorphosis. Although PINK1/PARKIN represent the canonical pathway for the elimination of impaired mitochondria in varied pathological conditions, their roles in developmental processes or normal physiological conditions have been less studied. To examine the potential contribution of PINK1 in developmental processes, we monitored the dynamic expression pattern of PINK1 in the midgut development by taking advantage of a newly CRISPR/Cas9 generated knock-in fly strain expressing PINK1-mCherry fusion protein that presumably recapitulates the endogenous expression pattern of PINK1. We disclosed a spatiotemporal correlation between the expression pattern of PINK1 and the mitochondrial clearance or persistence in ECs or ISCs respectively. By mosaic genetic analysis, we then demonstrated that PINK1 and PARKIN function epistatically to mediate the specific timely removal of mitochondria, and are involved in global autophagy in ECs during Drosophila midgut metamorphosis, with kinase-dead PINK1 exerting dominant negative effects. Taken together, our studies concluded that the PINK1/PARKIN is crucial for timely cell-type specific mitophagy under physiological conditions and demonstrated again that Drosophila midgut metamorphosis might serve as an elegant in vivo model to study autophagy., (Copyright © 2016 Elsevier Inc. All rights reserved.)

An FAD-dependent glucose dehydrogenase (FAD-GDH) from Aspergillus terreus NIH2624 was expressed in Escherichia coli with a yield of 228±16U/L of culture. Co-expression with chaperones DnaK/DnaJ/GrpE and osmotic stress induced by simple carbon sources enhanced productivity significantly, improving the yield to 23883±563U/L after optimization. FAD-GDH was purified in two steps with the specific activity of 604U/mg. Using d-glucose as substrate, the optimal pH and temperature for FAD-GDH were determined to be 7.5 and 50°C, respectively. Activity was stable across the pH range 3.5-9.0, and the half-life was 52min at 42°C. Km and Vmax were calculated as 86.7±5.3mM and 928±35U/mg, and the molecular weight was approximately 65.6kDa based on size exclusion chromatography, indicating a monomeric structure. The 3D structure of FAD-GDH was simulated by homology modelling using the structure of A. niger glucose oxidase (GOD) as template. From the model, His551, His508, Asn506 and Arg504 were identified as key residues, and their importance was verified by site-directed mutagenesis. Furthermore, three additional mutants (Arg84Ala, Tyr340Phe and Tyr406Phe) were generated and all exhibited a higher degree of substrate specificity than the native enzyme. These results extend our understanding of the structure and function of FAD-GDH, and could assist potential commercial applications., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Soil salinity is known to enhance cadmium (Cd) accumulation in crops. However, the mechanism by which this occurs independent of the surrounding soil remains unclear. In this study, root adsorption and uptake of salt cations and Cd by edible amaranth under NaCl salinity stress were investigated in hydroponic cultures with 0, 40, 80, 120, and 160mM of NaCl and 27nM Cd. The dominant Cd species in the nutrient solution changed from free Cd(2+) to Cd chlorocomplexes as NaCl salinity increased. High salinity significantly reduced K, Ca, and Cd root adsorption and K, Ca, Mg, and Cd uptake. High salinity decreased root adsorption of Cd by 43 and 58 percent and Cd uptake by 32 and 36 percent in salt-tolerant and salt-sensitive cultivars, respectively. Transformation of Cd from free ion to chlorocomplexes is unlikely to have significantly affected Cd uptake by the plant because of the very low Cd concentrations involved. Application of Ca ion channel blocker significantly reduced Na, K, Ca, Mg, and Cd uptake by the roots, while blocking K ion channels significantly reduced Na and K uptake but not Ca, Mg, and Cd uptake. These results suggest that Na was absorbed by the roots through both Ca and K ion channels, while Cd was absorbed by the roots mainly through Ca ion channels and not K ion channels. Salinity caused a greater degree of reduction in Cd adsorption and uptake in the salt-sensitive cultivar than in the salt-tolerant cultivar. Thus, competition between Na and Cd for Ca ion channels can reduce Cd uptake at very low Cd concentrations in the nutrient solution., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The impact of typical pollutants upon the fish-farming was assessed by use of a battery of biomarkers in two typical marine aquaculture regions in South China. Biotransformation parameters including 7-ethoxyresorufin-O-deethylase (EROD), aminopyrine N-demethylase (APND), erythromycin N-demethylase (ERND), glutathione-S-transferase (GST) and Malondialdehyde (MDA) were measured in five cultured fish species. Pollutants such as polycyclic aromatic hydrocarbon (PAHs), organochlorinated compounds (OCs), heavy metals and antibiotics (quinolones and sulfonamides) in sediments were characterized. Higher pollutant residue levels were observed in Dapeng Cove. EROD, APND and ERND activities were lower in fish from Dapeng Cove compared with fish from Hailing Island, while it is just on the contrary for GST and MDA. ERND, APND and GST showed sensitivity corresponding to different pollutants. Small fish species seemed to exhibit more sensitive to pollutants. The study further supports usefulness of multi-biomarker approach considering multiple species to define the effects of anthropogenic inputs in marine aquaculture systems., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The concentrations and distribution of polychlorinated biphenyls were determined in water, surface sediments and fishes from the estuaries of Pearl River, PR China. The results showed that the concentrations ranged from 2.47 ng l-1 to 6.75 ng l-1 in water, from 11.13 ng g-1 to 23.23 ng g-1 in sediments (dry weight) and from 68.64 ng g-1 to 316.85 ng-1 in fish (lipid weight). It was found that the feeding habits of fish were very significant in the accumulation of polychlorinated biphenyls and pattern of congeners. Carnivorous and benthic fishes such as eel (Anguilla japonica) and Chinese sea catfish (Arius sinensis) were found to have high concentrations of polychlorinated biphenyls and of high-chlorinated congeners, while herbivores such as shad (Clupanodon punctatus) and mullet (Mugil cephalus) exhibited an opposite trend. Congeners IUPAC Nos. 153, 138, 118, 87/81, 170 and 52 were found frequently in most samples (both sediment and fish). In comparison with other places in the world, the concentration of polychlorinated biphenyls in sediment and fish from the estuary of Pearl River were low.