Today, pathogenic microorganisms are increasingly developing resistance to conventional drugs, necessitating the exploration of alternative strategies. In addressing this challenge, nano-based antibacterial agents offer a promising avenue of research. In the present study, we used an extract of Moringa oleifera, a widely recognized edible and medicinal plant, to synthesize biogenetic tellurium nanoparticles (Bio-TeNPs). Transmission electron microscopy, scanning electron microscopy, and dynamic light scattering analyses revealed that the obtained Bio-TeNPs had diameters between 20 and 50 nm, and zeta potential values of 23.7 ± 3.3 mV. Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that the Bio-TeNPs consisted primarily of Te(0), along with some organic constituents. Remarkably, these Bio-TeNPs exhibited potent antibacterial activity against a spectrum of pathogens, including Escherichia coli, Klebsiella pneumoniae, Shigella dysenteriae, Salmonella typhimurium, Streptococcus pneumoniae, and Streptococcus agalactiae. In addition, findings from growth curve experiments, live/dead cell staining, and scanning electron microscopy observations of cell morphology demonstrated that Bio-TeNPs at a concentration of 0.07 mg/mL effectively disrupted E. coli and K. pneumoniae cells, leading to cell rupture or shrinkage. The biofilm inhibition rates of 0.7 mg/mL Bio-TeNPs against E. coli and K. pneumoniae reached 92% and 90%, respectively. In addition, 7 mg/mL Bio-TeNPs effectively eradicated E. coli from the surfaces of glass slides, with a 100% clearance rate. These outcomes underscore the exceptional antibacterial efficacy of Bio-TeNPs and highlight their potential as promising nanomaterials for combating bacterial infections.

A capture systematic evolution of ligands by exponential enrichment (Capture-SELEX) was described to discover novel aptamers specific for 5-hydroxymethylfurfural (5-HMF), and a biosensor based on molecular beacon was constructed to detect 5-HMF. The ssDNA library was immobilized to streptavidin (SA) resin to select the specific aptamer. The selection progress was monitored using real-time quantitative PCR (Q-PCR), and the enriched library was sequenced by high-throughput sequencing (HTS). Candidate and mutant aptamers were selected and identified by Isothermal Titration Calorimetry (ITC). The FAM-aptamer and BHQ1-cDNA were designed as the quenching biosensor to detect 5-HMF in milk matrix. After the 18th round selection, the Ct value decreased from 9.09 to 8.79, indicating that the library was enriched. The HTS results indicated that the total sequence numbers for 9th, 13th, 16th, and 18th were 417054, 407987, 307666, and 259867, but the number of sequences for the top 300 sequences was gradually increased from 9th to 18th, and the ClustalX2 analysis showed that there were four families with high homology rate. ITC results indicated that the K_d values of H1 and its mutants H1-8, H1-12, H1-14, and H1-21 were 2.5 μM, 1.8 μM, 1.2 μM, 6.5 μM, and 4.7 μM. The linear range of the quenching biosensor was from 0 μM to 75 μM, and it had a similar linear range in the 0.1% milk matrix. This is the first report to select a novel aptamer specific for 5-HMF and develop quenching biosensor for the rapid detection of 5-HMF in milk matrix.

Understanding changes in the distribution and coverage of aquatic vegetation (AV) is of great significance for the restoration of lake ecosystems. In this study, the vegetation and bloom indices (VBI) algorithm were used to interpret submerged aquatic vegetation (SAV), floating/emergent aquatic vegetation (FEAV), and algal bloom (AB). The dynamics of AV and their influencing factors in Bao’ an Lake, in the middle reaches of the Yangtze River in China, were studied from 2000 to 2023. The results showed that (1) the VBI algorithm can accurately distinguish AV and AB of different life forms with an overall accuracy of 93% and a kappa coefficient of 0.86. (2) Macrophyte coverage decreases. AV grew vigorously in spring, and SAV was the dominant type within it, whereas AV coverage was low in summer, and SAV had no summer species for a long time. In 2000, the coverage of AV was the highest, reaching 64.5%, but a gradual decrease that followed in the coming years finally led to a coverage percentage of less than 5% by 2023. (3) The correlation between SAV coverage and total phosphorus (p < 0.01), total nitrogen (p < 0.05), and water depth/transparency (p < 0.05) in Bao’ an Lake were 0.23, 0.28, and 0.32, respectively. (4) The SAV species experienced three stages: richness (before 2003), monotonicity (2004–2020), and final disappearance (2021–present). This study shows that the coverage of AV in Bao’ an Lake is too low and the number of SAV species is one (2010–now). Therefore, it is necessary to implement measures to improve vegetation coverage and diversity.

Nutrients, organic matter (OM), and heavy metals (HMs) in lake sediments are critical elements contributing to water pollution. In April 2019, surface sediments from Wanghu Lake were collected, and the nutrient, organic matter, and heavy metal content of the sediments were determined. We mainly evaluated the sediment pollutants through four evaluation methods to assess pollution and provide a reference for pollution control in Wanghu Lake. The results indicated that the averages of total phosphorus (TP) and total nitrogen (TN) were (1045.74 ± 190.17) mg/kg, (945.27 ± 203.56) mg/kg; most of them showed serious pollution and moderate pollution, respectively. OM was (32.31 ± 5.11) g/kg. Among them, TP and OM in the northwestern Wanghu Lake were significantly higher than those in the eastern lake (p < 0.05). It shows that nutrients are greatly affected by historical aquaculture and urban human activities. TP was the most serious in the center of the lake, and the source of pollution was mainly the historical deposition. The average of Cd, Cr, Cu, Ni, Pb, Zn, Hg, and As in the sediments were 2.15, 1.09, 1.93, 1.37, 1.28, 1.49, 2.60, 1.77 times that of the soil background values of Hubei Province, respectively. Hg and Cd were the main factors contributing to the surface sediments, with levels at considerable and moderate risks, respectively.

Ultraplankton plays an important role in the biogeochemical cycles of aquatic ecosystems. Based on 16S rRNA gene sequencing technology, the community structure composition of prokaryotic ultraplankton and its relationship with environmental factors were analyzed. The results showed that Cihu Lake was experiencing eutrophication and that Xiandao Lake was in the process of changing from mesotrophic to oligotrophic conditions. Cihu Lake and Xiandao Lake were regulated primarily by nitrogen nutrients. Proteobacteria, Bacteroidota, Cyanobacteria, and Actinobacteriota were the major phyla of prokaryotic ultraplankton in both lakes. Among them, Cyanobacteria dominate in the summer in Cihu Lake, which can have seasonal cyanobacterial blooms. Seasonal variation significantly affects the diversity and community structure of prokaryotic ultraplankton in the lakes, with temperature and dissolved oxygen being the key environmental factors determining plankton community composition. The PICRUSt functional prediction analysis indicated a higher water purification and exogenous pollution remediation capacity of the microbial communities of Xiandao Lake, as well as in the spring samples of Cihu Lake. In this study, the diversity and spatial–temporal succession patterns of prokaryotic ultraplankton in Cihu Lake and Xiandao Lake were elucidated, providing a useful reference for the lake environmental protection and water eutrophication management in Cihu Lake and Xiandao Lake.