The contribution of seasonal variations and Zostera marina presence to the bacterial community assembly of seagrass bed sediments.

Background: Microorganisms play pivotal roles in seagrass ecosystems by facilitating material and elemental cycling as well as energy flux. However, our understanding of how seasonal factors and seagrass presence influence the assembly of bacterial communities in seagrass bed sediments is limited. Employing high-throughput sequencing techniques, this study investigates and characterizes bacterial communities in the rhizosphere of eelgrass (Zostera marina) and the bulk sediments across different seasons.

The causal link between nitrogen structure and physiological processes of Ulva prolifera as the causative species of green tides.

Harmful algal blooms (HABs) increase with eutrophication depending on the nutrient structure (availability and ratios), but an unequivocal causal link between these factors is rarely established. Here, we provide support for the causal link between the nitrogen structure and physiological processes of Ulva prolifera as the causative species of Yellow Sea green tides (YSGTs) using in situ and laboratory experiments. The results showed that the components of nitrogen nutrients in seawater exhibited significant spatiotemporal variation.

Distribution Control and Environmental Fate of PFAS in the Offshore Region Adjacent to the Yangtze River Estuary─A Study Combining Multiple Phases Analysis.

The Yangtze River Estuary is the terminal sink of terrestrial per- and polyfluoroalkyl substances (PFAS) from the Yangtze River, while the environmental fate characteristics of legacy and emerging PFAS around this region have rarely been discussed. Here, 24 targeted PFAS in seawater, sediments, suspended particulate matter (SPM), and plankton in the offshore region adjacent to this estuary were investigated. The three dominant PFAS in all phases were perfluorooctanoic acid (PFOA, 23.

Community structure of endophytic bacteria of Sargassum thubergii in the intertidal zone of Qingdao in China.

Endophytic bacteria are one of the symbiotic microbial groups closely related to host algae. However, less research on the endophytic bacteria of marine algae. In this study, the endophytic bacterial community of Sargassum thunbergii was investigated using the culture method and high-throughput sequencing.

The host sex contributes to the endophytic bacterial community in and their receptacles.

Endophytic bacteria have a complex coevolutionary relationship with their host macroalgae. Dioecious macroalgae are important producers in marine ecosystems, but there is still a lack of research on how sex influences their endophytic bacteria. In this study, the endophytic bacterial communities in male and female and their reproductive tissues (receptacles) were compared using culture methods and high-throughput sequencing.

Reactive oxygen species mediated extracellular polymeric substances production assisting the recovery of Thalassiosira pseudonana from polystyrene micro and nanoplastics exposure.

As emerging pollutants in the aquatic environments, micro- and nano-plastics (MNPs) aroused widespread environmental concerns for their potential threats to the ecological health. Previous research has proved that microalgae growth could recover from the MNPs toxicities, in which the extracellular polymeric substances (EPS) might play the key role. In order to comprehensively investigate the recovery process of microalgae from MNPs stress and the effecting mechanisms of EPS therein, this study conducted a series of experiments by employing two sizes (0.

Acclimation of intertidal macroalgae Ulva prolifera to UVB radiation: the important role of alternative oxidase.

Background: Solar radiation is primarily composed of ultraviolet radiation (UVR, 200 - 400 nm) and photosynthetically active radiation (PAR, 400 - 700 nm). Ultraviolet-B (UVB) radiation accounts for only a small proportion of sunlight, and it is the primary cause of plant photodamage. The use of chlorofluorocarbons (CFCs) as refrigerants caused serious ozone depletion in the 1980s, and this had led to an increase in UVB.

Behavioral toxicity of TDCPP in marine zooplankton: Evidence from feeding and swimming responses, molecular dynamics and metabolomics of rotifers.

As new organic flame retardants, chlorinated organophosphate esters (Cl-OPEs) have high water solubility and structural similarity to organophosphate pesticides, posing risks to aquatic organisms. The potential neurotoxicity of Cl-OPEs has attracted attention, especially in marine invertebrates with a relatively simple nervous system. In this study, a marine rotifer with a cerebral ganglion, Brachionus plicatilis, was exposed to tris (1,3-dichloro-2-propyl) phosphate (TDCPP) (two environmental concentrations and one extreme level), and the changes in feeding and swimming behaviors and internal mechanism were explored.

Molecular insight into the binding properties of marine algogenic dissolved organic matter for polybrominated diphenyl ethers and their combined effect on marine zooplankton.

Polybrominated diphenyl ethers (PBDEs) are widespread in marine ecosystems, despite the limits placed on several congeners, and pose a threat to marine organisms. Many coexisting factors, especially dissolved organic matter (DOM), affect the environmental behavior and ecological risk of PBDEs. Since blooms frequently occur in coastal waters, we used algogenic DOM (A-DOM) from the diatom Skeletonem costatum and examined the interaction of A-DOM with 2,2',4,4'-tetrabromodiphenyl ether (BDE-47).

ROS meditated paralytic shellfish toxins production changes of Alexandrium tamarense caused by microplastic particles.

A variety of studies have investigated the toxic effects of microplastics (MPs) on microalgae, but few of them considered their influence on dinoflagellate toxins production, which could cause significant ecological safety concerns in coastal areas. This research investigated the impacts of 5 μg L and 5 mg L polystyrene (PS) MPs on the changes of paralytic shellfish toxins (PSTs) production and their relationship with cellular oxidative stress of Alexandrium tamarense, a common harmful algal blooms causative dinoflagellate. The results showed elevation of reactive oxygen species (ROS) levels, activation of antioxidant system and overproduction of PSTs were positively correlated under PS MPs exposure (especially under 5 mg L PS MPs), and the PSTs changes were eliminated by the ROS inhibitor.

The Isolation of Anaerobic and Facultative Anaerobic Sulfate-Reducing Bacteria (SRB) and a Comparison of Related Enzymes in Their Sulfate Reduction Pathways.

Sulfate-reducing bacteria (SRB) are an important group of microorganisms that cause microbial corrosion. In this study, culturable SRB were isolated and identified from the inner rust layer of three kinds of steel and from sediments, and a comparison of amino acid sequences encoding related enzymes in the sulfate reduction pathway between anaerobic and facultative anaerobic SRB strains was carried out. The main results are as follows.

Tributyl phosphate can inhibit the feeding behavior of rotifers by altering the axoneme structure, neuronal coordination and energy supply required for motile cilia.

Organophosphorus flame retardants (OPFRs) are frequently detected in aquatic environments and can potentially amplify the food chain, posing a potential risk to organisms. Marine invertebrates have primitive nervous systems to regulate behavior, but how they respond to OPFRs that are potentially neurotoxic substances is unclear. This study assessed changes in the feeding behavior of rotifer Brachionus plicatilis exposed to alkyl OPFRs tributyl phosphate (TnBP) (0.

Luteolin induces apoptosis by impairing mitochondrial function and targeting the intrinsic apoptosis pathway in gastric cancer cells.

Gastric cancer is one of the most lethal cancers worldwide. Research has focused on exploring natural medicines to improve the systematic chemotherapy for gastric cancer. Luteolin, a natural flavonoid, possesses anticancer activities.

UV-B radiation alleviated detrimental effects of polymethyl methacrylate microplastics on marine diatom Thalassiosira pseudonana.

Microplastics (MPs) in marine environments simultaneously affect microalgae with UV-B radiation, while their joint effecting mechanisms remain largely unknown. To fill this research gap, the joint effects of polymethyl methacrylate (PMMA) MPs and UV-B radiation (natural environments intensity) on the model marine diatom Thalassiosira pseudonana were investigated. Antagonism was found between the two factors with regards to population growth.

Studies on the Composition and Diversity of Seagrass Rhizosphere Mmicroorganisms in the Yellow River Delta.

Seagrass is a significant primary producer of coastal ecosystems; however, the continued degradation of seagrass beds is a serious problem that has attracted widespread attention from researchers. Rhizosphere microorganisms affect seagrass and participate in many life activities of seagrass. This study explored the relationship between the composition of microbes in the rhizosphere and the surrounding environment of by using High-throughput sequencing methods.

Peroxidase-like phosphate hydrate nanosheets bio-synthesized by a marine Shewanella algae strain for highly sensitive dopamine detection.

The sensitive and rapid detection of dopamine (DA) is of great significance for early diagnosis of related diseases. Current detection strategies of DA are time-consuming, expensive and inaccurate, while biosynthetic nanomaterials were considered highly stable and environment friendly, which were promising on colorimetric sensing. Thus, in this study, novel zinc phosphate hydrate nanosheets (SA@ZnPNS) biosynthesized by Shewanella algae were designed for the detection of DA.

Effects of UV-B radiation on epiphytic bacterial communities on male and female Sargassum thunbergii.

The effects of increased UV-B radiation on macroalgae have been widely studied, but knowledge concerning the response of communities of algal epiphytic bacteria to increased UV-B radiation and differences between male and female algae is still lacking. Via 16S rDNA high-throughput sequencing technology, changes in the epiphytic bacterial communities on male and female S. thunbergii under increased UV-B radiation were studied in the lab.

Chloroplast genomic comparison provides insights into the evolution of seagrasses.

Background: Seagrasses are a polyphyletic group of monocotyledonous angiosperms that have evolved to live entirely submerged in marine waters. Thus, these species are ideal for studying plant adaptation to marine environments. Herein, we sequenced the chloroplast (cp) genomes of two seagrass species (Zostera muelleri and Halophila ovalis) and performed a comparative analysis of them with 10 previously published seagrasses, resulting in various novel findings.

The inhibition and recovery mechanisms of the diatom Phaeodactylum tricornutum in response to high light stress - A study combining physiological and transcriptional analysis.

By combining physiological/biochemical and transcriptional analysis, the inhibition and recovery mechanisms of Phaeodactylum tricornutum in response to extreme high light stress (1300 μmol photons · m  · s ) were elucidated. The population growth was inhibited in the first 24 h and started to recover from 48 h. At 24 h, photoinhibition was exhibited as the changes of PSII photosynthetic parameters and decrease in cellular pigments, corresponding to the downregulation of genes encoding light-harvesting complex and pigments synthesis.

Structure-Function Covariation of Phycospheric Microorganisms Associated with the Typical Cross-Regional Harmful Macroalgal Bloom.

Unravelling the structure-function variation of phycospheric microorganisms and its ecological correlation with harmful macroalgal blooms (HMBs) is a challenging research topic that remains unclear in the natural dynamic process of HMBs. During the world's largest green tide bloom, causative macroalgae experienced dramatic changes in growth state and environmental conditions, providing ideal scenarios for this investment. Here, we assess the phycospheric physicochemical characteristics, the algal host's biology, the phycospheric bacterial constitutive patterns, and the functional potential during the .