We report an Illumina high-throughput sequencing protocol of eukaryotic microbes in the world’s deepest marine blue hole, Sansha Yongle Blue Hole, Xisha, South China Sea. The variable V9 region of small subunit (SSU) rDNA, was sequenced using this approach from the waters of blue hole and outer reef slope. 917,771 unique eukaryotic 18S rRNA gene sequences and 6093 operational taxonomic units (OTUs) were identified. Significant differences in the eukaryotic composition were observed between the blue hole and outer reef slope, and the richness in the blue hole was much higher than that in the outer reef slope. The richness and diversity of eukaryotes in the blue hole were both lowest at 60 m and highest at 100 m depth. Eukaryotic microalgae assemblages dominated by Dinophyceae were the most abundant in the 10–20 m water column in the hole. Fauna was the main group at and below a depth of 60 m, where Araneae and Cyclopoida were dominant in the 60 m and 80 m water layer, respectively. There was a large number of Entoprocta at a depth of 180 m in the hole, where little oxygen was detected. Turbidity and nitrite concentration had a significant effect on the eukaryote community structure (p < 0.01).

Due to the increase in nanoplastics (NPs) abundance in aquatic environments, their effects on phytoplankton have aroused large research attention. In this study, 100 nm sized polystyrene NPs were chosen to investigate their effecting performance and mechanisms on a typical dinoflagellates Alexandrium tamarense. The results indicated the population growth and photosynthetic efficiencies of A. tamarense were significantly inhibited by NPs exposure, as well as the increase in cellular total carotenoids and paralytic shellfish toxins (PSTs). Meanwhile, the cellar ROS levels increased, corresponding to the increased activities or contents of multiple antioxidant components, including SOD, CAT, GPX, GR, GSH and GSSG. The transcriptional results support the physiological–biochemical results and further revealed the down-regulation of genes encoding the light reaction centers (PSI and PSII) and up-regulation of genes encoding the antioxidant components. Up-regulation of genes encoding key enzymes of the Calvin cycle and glycolytic pathway together with the TCA cycle could accelerate organic carbon and ATP production for A. tamarense cells resistant to NPs stress. Finally, more Glu and acetyl-CoA produced by the enhanced GSH cycle and the glycolytic pathway, respectively, accompanied by the up-regulation of Glu and Arg biosynthesis genes supported the increase in the PST contents under NPs exposure. This study established a data set involving physiological–biochemical changes and gene information about marine dinoflagellates responding to NPs, providing a data basis for further evaluating the ecological risk of NPs in marine environments.

Despite the importance of surface microbiota in postharvest quality, the effects of mechanical damage on microbial succession in Hypsizygus marmoreus during refrigerated storage remain insufficiently understood. In this study, 16S rRNA gene and ITS amplicon sequencing were used to characterize the bacterial and fungal communities on intact and mechanically damaged H. marmoreus during 15 days of storage at 4 °C. Storage time, rather than mechanical damage, was the main driver of whole-community variation, although mechanical damage accelerated visible spoilage assessed qualitatively. Bacterial communities showed pronounced temporal turnover, shifting from early Firmicutes-rich assemblages to late-stage Proteobacteria-dominated communities, especially Pseudomonas. In contrast, fungal communities remained largely dominated by Ascomycota throughout storage, although mechanically damaged mushrooms showed a greater late-stage occurrence of opportunistic yeasts such as Candida. Predicted functional and phenotypic analyses further suggested late-stage increases in Gram-negative, aerobic, biofilm-forming, stress-tolerant, and potentially pathogenic bacterial traits. Because these traits were inferred from 16S rRNA gene-based prediction rather than measured directly, they should be interpreted cautiously. Overall, the results suggest that maintaining the physical integrity of H. marmoreus during postharvest handling may help preserve quality and delay the emergence of spoilage-associated microbial traits during refrigerated storage.

The YanTai HY-Nuclear Power Plant (HYNPP) is a newly constructed nuclear power plant that entered operation after 2021. To establish a preoperational ecological baseline for the HYNPP, this study examined macrobenthic community structure and its relationships with multiple environmental variables using year-round field surveys conducted from 2016 to 2017. Eighty-five species from eight phyla were recorded in total, with winter showing the highest species number and spring exhibiting peak biomass. Species composition displayed pronounced seasonal turnover, with replacement rates exceeding 93% between adjacent seasons. Principal coordinates analysis (PCoA) and hierarchical clustering confirmed significant seasonal variation and the localized aggregation of species near the HYNPP. Diversity indices (S, H′, D′, and J′) varied across seasons and spatial gradients, strongly influenced by sea bottom temperature (SBT), salinity, dissolved oxygen (DO), and nutrient concentrations. Spearman correlation analysis and random forest (RF) modeling revealed SBT, DO, phosphate, and phytoplankton cell as dominant factors shaping macrobenthic diversity. RF models provided key insights into nonlinear interactions and variable importance across seasons. Leveraging the dependence-preserving power of copulas, Copula-Based Random Forest (CBRF) models were further developed under a +4°C warming scenario to simulate post-operational thermal-discharge effects; the CBRF framework captured complex spatial responses, predicting localized biomass increases in sheltered muddy areas and biomass reductions in the outer bay. Mollusk biomass was projected to peak in spring near mixed-substrate habitats, while annelids and arthropods showed variable responses linked to sediment type and nutrient availability. These findings highlight strong spatiotemporal coupling between environmental parameters and macrobenthic assemblages, emphasizing the roles of SBT and phytoplankton-driven organic inputs in modulating community structure. The predictive framework built here supports long-term ecological risk assessments and management strategies for mitigating thermal discharge impacts in the Yellow Sea region.

Coastal ecosystems are critical biogeochemical reactors and biodiversity reservoirs, yet the mechanisms governing the community connectivity and stability of their foundational microbiomes remain poorly understood, particularly in anthropogenically influenced coastal oceans. Here, we systematically analyzed prokaryotic and microeukaryotic communities along both vertical and horizontal gradients in the Bohai-Yellow Sea, a model anthropogenically influenced and multi-stressed coastal ocean. We found that horizontal gradients, primarily driven by distance to coastline and latitudinal transitions, surpassed vertical gradients as the principal force governing microbial community assembly, connectivity, and stability. These horizontal factors overwhelmingly shaped microbial diversity, niche breadth, and biogeographic patterns, with prokaryotes displaying broader environmental adaptability and stronger cross-regional dispersal potential than microeukaryotes. Consequently, prokaryotes maintained higher spatial connectivity than microeukaryotes across both dimensions. This prokaryotic connectivity advantage was most pronounced within intermediate water masses. In contrast, vertical connectivity weakened with intensified water column stratification from the well-mixed Bohai Sea to the hydrographically complex South Yellow Sea. Horizontal gradients directly steered microbial co-occurrence network properties, driving a depth-dependent decline in network complexity and stability. This regional disparity was further underscored by distinct stability trade-offs: the semi-enclosed Bohai Sea fostered robust, modular networks, whereas the Yellow Sea systems formed highly connected but less modular, and thus more vulnerable, network architectures. Our findings reveal a dominant horizontal connectivity mode in coastal microbiomes, establishing a mechanistic link between large-scale environmental gradients and microbial network stability. This is a crucial advance for predicting ecological responses to anthropogenic and climate perturbations in vulnerable coastal zones. IMPORTANCE: Coastal microbial communities drive global biogeochemical cycles, yet the principles governing their large-scale connectivity and microbial network stability remain elusive, particularly in anthropogenic disturbances regions. Focusing on the Bohai-Yellow Sea system, we establish that horizontal transport processes, modulated by land-sea exchange and latitudinal gradients, override vertical stratification as the dominant force structuring microbial assembly and interaction networks. We demonstrate that prokaryotes possess a stronger horizontal dispersal advantage than microeukaryotes, sustaining higher connectivity through intermediate water layers. This horizontal connectivity governs microbial network stability. Networks shift from robust, prokaryote-driven modular architectures in shallow coastal waters to fragile, microeukaryote-dominated patterns in deeper, stratified regions. These findings define a “horizontal connectivity mode” as a central organizing principle for coastal microbiomes, moving beyond descriptive biogeography to provide a mechanistic framework for predicting community resilience to anthropogenic and climate forcing.

Introduction: Mulberry ( Morus alba L.) leaves (MLs), a well-known food-medicine homologous substance, possess potent properties against oxidative stress. However, the impact of industrial drying methods on their antioxidant activity is still not completely clear. Methods: A comprehensive approach based on UPLC-MS/MS metabolomics, network pharmacology and molecular docking was employed to find the active compounds in MLs treated by different drying methods and their potential antioxidant mechanisms in this study. Results and discussion: A total of 1467 metabolites were detected through UPLC-MS/MS analysis, and differential metabolites of MLs were searched by multivariate statistical analysis. Hot-air dried MLs exhibited the highest DPPH and ABTS radical scavenging capacities, as well as the strongest ferric reducing antioxidant power. This enhanced activity might be attributed to the maximal hydrolysis of kaempferol glycosides, leading to the significant accumulation of free kaempferol. Network pharmacology analysis further revealed that the bioactive compounds in MLs exerted their antioxidant effects by targeting key proteins, including AKT1, TNF, ALB, IL-1B, and BCL2. These findings provided valuable insights into how different drying methods influenced the antioxidant property of MLs.