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The widespread application of nanoparticles (NPs) in agriculture has not only enhanced the efficiency of agrochemical use but also introduced environmental pollution, potentially impacting human health through absorption and accumulation in edible plants. The purpose of this study was to evaluate the toxic effects and ecological risks of Cu2O nanoparticles (nCu2O) in the life cycle of soybean, and to provide a theoretical basis for the safe application of NPs in agriculture. Soybeans were grown in natural soil modified with nCu2O, bulk cuprous oxide (bCu2O) and copper sulfate (CuSO4) at concentrations of 0, 50, 200, and 800 mg/kg. Samples and grains from treated soybeans were collected at the flowering, podding, and seed-filling stages for analysis. The results indicated that treatments with nCu2O, bCu2O, and Cu2+ reduced the chlorophyll content in soybean leaves, thereby affecting photosynthesis. Significant reductions were observed in the net photosynthetic rate (Pn), the transpiration rate (Tr), stomatal conductance (Gs), the quantum yield of photosystem II (Y(II)), photochemical quenching (qP), and the electron transport rate (ETR) at high concentrations. However, the toxicity of nCu2O to photosynthesis recovers as the plant grows. Almost all treatments increased the levels of antioxidant enzymes (SOD, POD, CAT) and reduced oxidative stress. In the nCu2O and bCu2O treatments, grain protein content was significantly reduced, while fat and water content increased. Phosphorus (P) content decreased, whereas sulfur (S), potassium (K), magnesium (Mg) and calcium (Ca) contents increased. The accumulation of copper in plants followed the order nCu2O > bCu2O > Cu2+, with the bCu2O treatment being slightly more toxic than the nCu2O treatment, and both being more toxic than the Cu2+ treatment. The above data indicated that nCu2O had a dose-dependent effect, which significantly inhibited soybean growth and changed grain quality at high concentrations. [ABSTRACT FROM AUTHOR]

Z-scheme Bi2MoO6/Bi5O7I heterojunction was constructed by an in situ solvothermal method, which was composed of Bi2MoO6 nanosheets growing on the surface of Bi5O7I microrods. The antibacterial activities under illumination towards Escherichia coli (E. coli) were investigated. The Bi2MoO6/Bi5O7I composites exhibited more outstanding antibacterial performance than pure Bi2MoO6 and Bi5O7I, and the E. coli (108 cfu/mL) was completely inactivated by BM/BI-3 under 90 min irradiation. Additionally, the experiment of adding scavengers revealed that h+, •O2− and •OH played an important role in the E. coli inactivation process. The E. coli cell membrane was damaged by the oxidation of h+, •O2− and •OH, and the intracellular components (K+, DNA) subsequently released, which ultimately triggered the apoptosis of the E. coli cell. The enhanced antibacterial performance of Bi2MoO6/Bi5O7I heterojunction is due to the formation of Z-scheme heterojunction with the effective charge transfer via the well-contacted interface of Bi2MoO6 and Bi5O7I. This study provides useful guidance on how to construct Bi5O7I-based heterojunction for water disinfection with abundant solar energy. [ABSTRACT FROM AUTHOR]

A high-performance liquid chromatograph with diode array detector was established for the simultaneous determination of five phenylethanoid glycosides in Syringa pubescens Turcz. The optimal chromatographic conditions were achieved on a Zorbax C18 column using gradient elution with 0.5% aqueous acetic acid and acetonitrile as the mobile phase at the flow rate of 1.0 mL/min. The detection wavelength was developed as follows: 0–10 min, 276 nm; 10–45 min, 332 nm. The validation of the method including linearity, precision, stability, accuracy, repeatability and recovery was tested. The chemometric analysis including hierarchical cluster analysis and principal component analysis was employed to investigate the similarity and difference of samples from different geographical origin. The results revealed that S. pubescens samples were divided into four clusters based on the phenylethanoid glycosides contents. Antioxidant activity of extract was measured using three different methods including α,α-diphenyl-β-picrylhydrazyl and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical scavenging assays, and ferric reducing antioxidant power assay. Furthermore, different phenylethanoid glycosides exhibited different contribution to antioxidant capacities. This study provides a foundation for the quality evaluation and offers scientific data for the utilization of S. pubescens resources. [ABSTRACT FROM AUTHOR]

The development of efficient visible light-responsive photocatalysts is of great importance to the advancement of photocatalytic technology. Bi2MoO6 was prepared via the citric acid (CA)-assisted solvothermal method and characterized by XRD, SEM, UV-Vis DRS, BET, and PL. The photocatalytic performance of the synthesized material was evaluated by ciprofloxacin (CIP) degradation, Escherichia coli (E. coli) and Staphylococcus aureus (S. aures) inactivation under visible light. Bi2MoO6 prepared with 3 mmol amount of CA, namely BM-3, exhibits the optimal photocatalytic activity. The CIP degradation efficiency of BM-3 reaches 89. 5% within 100 min, which is 2.45 times higher than that of BM-0 prepared without CA. In addition, BM-3 could completely inactivate E. coli within 150 min or S. aures within 200 min, causing concave surfaces and cell aggregation due to the leakage of cellular contents. Multiple cycles of experimentation were conducted to validate the stability of BM-3. The wide visible light absorption range, large specific surface area, and efficient photogenerated carrier separation efficiency were key factors contributing to the superior photocatalytic performance of Bi2MoO6 synthesized by the CA-assisted solvothermal method. [ABSTRACT FROM AUTHOR]

Liquid exfoliation of bulk g-C3N5 was applied to synthesize g-C3N5 nanosheets. In order to characterize the samples, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectra (XPS), UV-Vis absorption spectra (UV-Vis), and photoluminescence spectra (PL) were examined. g-C3N5 nanosheets exhibited enhanced performance in the inactivation of Escherichia coli (E. coli) with visible light irradiation relative to bulk g-C3N5 and promoted complete inactivation of E. coli within 120 min. h+ and •O2− were the principal reactive species in the antibacterial process. In the early stages, SOD and CAT played a defensive role in resisting oxidative damage of active species. With the prolonged light exposure time, the antioxidant protection system was overwhelmed leading to the destruction of the cell membrane. The leakage of cell contents such as K+, protein, and DNA caused bacterial apoptosis ultimately. The enhanced photocatalytic antibacterial performance of g-C3N5 nanosheets is ascribed to the stronger redox property by the upward shift of CB and downward shift of VB compared with bulk g-C3N5. On the other hand, larger specific surface area and better separation efficiency of photoinduced carriers are helpful to the improved photocatalytic performance. This study systematically revealed the inactivation process toward E. coli and expanded the application range of g-C3N5-based materials with abundant solar energy. [ABSTRACT FROM AUTHOR]

In this paper, a novel S-scheme CuS/Bi5O7I heterojunction was successfully constructed using a two-step approach comprising the alkaline hydrothermal method and the adsorption–deposition method, and it consisted of Bi5O7I microrods with CuS particles covering the surface. The photocatalytic antibacterial effects on Escherichia coli (E. coli) were systematically examined with visible light exposure. The results suggested that the 3%-CuS/Bi5O7I composite showed the optimal antibacterial activity, completely inactivating E. coli (5 × 108 cfu/mL) in 180 min of irradiation. Moreover, the bacterial inactivation process was scientifically described. •O2− and h+ were the major active species for the inactivation of the bacteria. In the early stages, SOD and CAT initiated the protection system to avoid the oxidative destruction of the active species. Unfortunately, the antioxidant protection system was overwhelmed thereafter, which led to the destruction of the cell membrane, as evidenced by the microstructure changes in E. coli cells. Subsequently, the leakage of intracellular components including K+, proteins, and DNA resulted in the unavoidable death of E. coli. Due to the construction of the S-scheme heterojunction, the CuS/Bi5O7I composite displayed the boosted visible light harvesting, the high-efficiency separation of photogenerated electrons and holes, and a great redox capacity, contributing to an outstanding photocatalytic disinfection performance. This work offers a new opportunity for S-scheme Bi5O7I-based heterojunctions with potential application in water disinfection. [ABSTRACT FROM AUTHOR]

Photocatalytic technology is regarded as one of the most promising pathways to solve the global energy shortage and environmental crisis, and the development of efficient photocatalysts with visible tight response has always been a research hotspot in the photocatalytic field. As the continuation and development of traditional photocatalyst bismuth oxyhalides (BiOX, X = Cl, Br, I), the bismuth rich bismuth oxyhalides (BixOyXz) shows tunable band structure which benefit to improve the photocatalytic actively. The methods of controlled synthesis of BixOyXz were summarized, including solid phase thermal conversion method, alkaline precipitated on/hydrothermal/solvothermal method, etc. The photocatalytic applications of BixOyXz were also introduced in degrading organic pollutants, spitting water to hydrogen, reducing carbon dioxide and nitrogenization. Finally, the current problems and future development directions of BixOyXz were proposed. The review will deepen the understanding of BixOyXz and open new directions for the design and optimization bismuth-based photocatalytic materials for energy and environmental applications. [ABSTRACT FROM AUTHOR]

The pathogenic bacteria in water that threatens the human health and photocatalytic disinfection have been proven to be a cost-effective and promising green technology. It is significant and necessary to develop efficient, safe, and visible light-driven photocatalysts. In this study, Escherichia coli was used as model bacterium and the disinfection performance of prepared S-doped g-C3N4 nanosheets (S-CNNs) under visible light was investigated. The results showed that the synergistic effects of S doping and the unique 2D structure of S-CNNs enhanced the visible light absorption, enlarged the specific surface area and reduced the recombination of photogenerated charge carriers which is beneficial for promoting the photocatalytic disinfection of the E. coli. Scavenger experiments indicated •O2− and h+ were the predominant reactive species in the photocatalytic disinfection process. In addition, the kinetics of disinfection activity were fitted by the modified Hom model and the k2 value of S-CNNs is 0.0219 min−1, which is much higher than that of the bulk g-C3N4 (CN). This work has demonstrated efficient bacterial inactivation with S-CNNs under visible light irradiation. [ABSTRACT FROM AUTHOR]

On the basis of g-C3N4 nanosheets prepared by liquid phase ultrasonic exfoliation, Ag/g-C3N4 nanosheets were fabricated by loading Ag nanoparticles through the method of light reduction. The as-prepared samples were characterized by TEM, FT-IR, XRD, BET and transient photocurrent. The disinfection of Escherichia coli (E. coli) was studied to evaluate the photocatalytic activity under visible light. The photocatalytic antibacterial kinetics were researched by modified Horn model. The results show that 3% Ag/g-C3N4 nanosheets exhibit the optimal photocatalytic disinfection of E. coli and the k2 value of 3% Ag/g-C3N4 nanosheets is 2.99 times of bulk g-C3N4 and 1.45 times of 3% Ag/bulk g-C3N4. Large specific surface area and high photocarrier separation efficiency have resulted in the excellent photocatalytic antibacterial activity of 3% Ag/g-C3N4 nanosheets. [ABSTRACT FROM AUTHOR]

The medicinal insects are one of the most abundant renewable resources with remarkable therapeutic potentials. In this paper on the basis of a comprehensive consulting,sorting and analyzing of the ancient and modern medical literatures, the resource research history and present situation, pharmacological effects and mechanisms of medicinal insects in China are systematically summarized. Then the existing problems and development prospect of medicinal insect resource are discussed. This review would provide reference for further study of medicinal insect resource. [ABSTRACT FROM AUTHOR]