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Harmful algal blooms (HABs) resulting from eutrophication pose a major threat to ecosystems and human health, necessitating effective control measures. Allelochemicals have shown their importance in slowing down algal proliferation due to their proven efficacy and low ecological impacts. In this study, allelopathy tea polyphenols (TPs) and β-cyclodextrin were combined to prepare slow-release algicidal microcapsules, and the diversity of microbial community in the algal inhibition process was analyzed. Results showed that TP slow-release microcapsules had strong algicidal activity. When against Microcystis aeruginosa within 20 d, their constant inhibitory rate was up to 99% compared to the control group. Microbial diversity decreased with an increase in algae density, and the species richness and diversity of algae increased under the stress of TP slow-release microcapsules. The redundancy analysis showed that the environmental factors with impacts on the abundance and diversity of bacterial communities in descending order were dissolved oxygen, pH, and temperature. This study provides a theoretical basis for the application of TP slow-release microcapsules to actual water.

Ferrous sulfide (FeS) nanoparticles constitute an effective hexavalent chromium (Cr(VI)) treatment reagent. However, FeS nanoparticles aggregate easily, significantly limiting their engineering applicability. To overcome this shortcoming and further improve Cr(VI) removal efficiency, this study used tannic acid (TA) to modify FeS nanoparticles. The results demonstrated that TA-modified FeS nanoparticles, TA-nano-FeS, had a significantly reduced tendency to agglomerate, and maintained particle diameters of 10–100 nm, which were much shorter than diameters of FeS nanoparticles. In addition, TA-nano-FeS could combine the surface-active functional groups of TA. The maximum removal capacity of TA-nano-FeS was 381.04 mg/g, which was 2.92 and 1.83 times higher than those of TA and nano-FeS, respectively. Furthermore, the acidic condition was more beneficial for Cr(VI) removal, and the coexisting cations (Ca2+ and Mg2+) slightly decreased the removal efficiency of Cr(VI). Adsorption, reduction, and co-precipitation were the removal mechanisms, and the reaction products included FeCr2O4, Cr2O3, Fe2O3, Cr(OH)3, and S8. The results provided valuable information for the practical application of TA-nano-FeS in Cr(VI) removal.

The long-standing popularity of semiconductor photocatalysis, due to its great potential in a variety of applications, has resulted in the creation of numerous semiconductor photocatalysts, and it stimulated the development of various characterization methods. In this study, Fe2O3/Bi2WO6 composite with a flower-like microsphere and hierarchical structure was synthesized with the facile hydrothermal-impregnation method without any surfactants. X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible (UV–Vis) diffuse reflectance spectroscopy, and photoluminescence spectroscopy were used to characterize the structures of the samples. The specific surface area was estimated with the Brunauer-Emmett-Teller (BET) method, and pore size distribution was determined using the Barrett-Joyner-Halenda (BJH) method. The synthesized Fe2O3/Bi2WO6 composite had an average diameter of approximately 4 nm, with smaller specific surface area and larger pore diameter than those of pristine Bi2WO6. The results of XRD and SEM analyses confirmed that the composite was composed of Fe2O3 and Bi2WO6. The absorption edge of Bi2WO6 was at a wavelength of 460 nm. By contrast, the absorption edge of Fe2O3/Bi2WO6 to visible light was redshifted to 520 nm, with narrower bandgap width and stronger visible light response. It was also found that the main active substances in the degradation of microcystin-LR (MC-LR) were hydroxyl radicals (·OH) and electron holes (h+). Consequently, the results further showed that the heterojunction between Fe2O3 and Bi2WO6 can improve the charge transfer rate and effectively separate the photoinduced electrons and holes. Compared with Bi2WO6, Fe2O3/Bi2WO6 had no significant difference in the adsorption capacity of MC-LR and had more efficient photocatalytic degradation activity of MC-LR. The degradation rates of MC-LR by Fe2O3/Bi2WO6 and Bi2WO6 reached 80% and 56%, respectively. The degradation efficiency of MC-LR was affected by the initial pH value, initial Fe2O3/Bi2WO6 concentration, and initial MC-LR concentration.

In our previous study, we prepared the granules by embedding artemisinin into alginate-chitosan using microcapsule technology. These granules can release artemisinin sustainably and have a strong inhibitory effect on the growth of both single Microcystis aeruginosa and mixed algae. To safely and effectively use artemisinin sustained-release granules to control algal blooms, the ecotoxicity was studied by assessing their acute and chronic toxicity to Daphnia magna (D. magna) and Danio rerio (D. rerio), along with their antioxidant activities. The results showed that the 48-h median effective concentration (EC50) of pure artemisinin to D. magna was 24.54 mg/L and the 96-h median lethal concentration (LC50) of pure artemisinin to D. rerio was 68.08 mg/L. Both values were classified as intermediate toxicity according to the Organization for Economic Co-operation and Development (OECD). The optimal algae inhibitory concentration of artemisinin sustained-release granules (1 g/L) had low acute toxicity to both D. magna and D. rerio. The sustained-release granules had higher chronic toxicity to D. magna than to D. rerio. Partial indices of D. magna were inhibited by granules when the concentrations were larger than 0.1 g/L. Low granule concentration had an inductive effect on antioxidant enzyme activities in D. magna and D. rerio. With the increase of the exposure concentration and time, the enzyme activity presented a trend of first increasing and then decreasing, and the overall changes were significant. The change trend and range of enzyme activity indicated that the granules could cause serious oxidative stress to D. magna and D. rerio, and the changes were consistent with the results of toxicity experimentation.

Purpose: To investigate the osteogenic effect of nano-grade pearl powder(NPP)/chitosan-hyaluronic acid (C-HA)/recombinant human bone morphology protein-2 (rhBMP-2) artificial bone., Methods: A bone defect model with a diameter of 7 mm and a height of 10 mm was made at the distal end of the femur. NPP/C-HA stent containing rhBMP-2 was prepared according to the shape of the defect. No material was implanted in the defect as blank group. NPP/C-HA was used as the control group, NPP/C-HA/rhBMP-2 was implanted into the experimental group. At 4 weeks, 8 weeks, and 12 weeks, the bone effects of each component were detected by cone-beam CT(CBCT), H-E and Masson staining. Serum ALP activity and OCN in tissues to determine the osteogenic differentiation and osteogenesis maturity were detected. SPSS 18.0 software package was used for statistical analysis., Results: At 12 weeks, the defect was completely repaired in the experimental group. No immunological side effects such as inflammation and rejection were observed. At 8 and 12 weeks, CBCT showed that the experimental group had a higher CT value (Hounsfield units, HU) compared with the control group and the blank group(P<0.05). H-E and Masson staining showed that the experimental group had obvious new bone formation compared with the control group and the blank group at 8 weeks and 12 weeks, and ALP activity of the experimental group was significantly different from the control group and the blank group at 8 weeks. OCN immunohistochemical scoring of the experimental group was significantly different from the control group and the blank group(P<0.05)., Conclusions: NPP/C-HA/rhBMP-2 has good tissue fusion, osteoinductivity, osteoconductivity and osteogenicity, which is expected to provide more effective treatment for bone repair.

Objective: To study the effects of Bushen Zhuyun Decoction (BZD) on the reproductive capacity of mice., Methods: Totally 60 female Kunming mice were randomly divided into the experimental group and the control group. BZD was perfused by gastric tube to mice in the experimental group, twice daily. Meanwhile, mice in the control group were administered with normal saline by gastrogavage. Mice were sacrificed on the 10th day and the 20th day of medication respectively, 15 mice each time in each group. The serum levels of estradiol and progesterone were detected by radioimmunoassay. The morphological changes of uterus and ovary were observed using HE staining. The expressions of leukaemia inhibitory factor (LIF), epidermal growth factor (EGF), and calcitionin (CT) were determined using immunohistochemical assay., Results: Compared with the control group at the same time point, the weights of uterus and ovary increased, the serum levels of estradiol and progestogen increased, the expressions of LIF, CT, and EGF increased in the experimental group on the 10th day and the 20th day of medication (P <0.05, P <0.01). Better results were shown on the 20th day of medication (P <0.05). Histological results showed increased ovarian follicle numbers, increased endometrial gland numbers, endometrial hyperplasia (stratiform arranged), and increased stromal cells in the experimental group, especially on the 20th day of medication., Conclusion: BZD could improve the reproductive capacity by advancing the development of generative organs, promoting the secretion of estradiol and progestogen and the follicular growth, and increasing the receptivity of endometrium.