Optimization of degradation conditions for sulfachlorpyridazine by Bacillus sp. DLY-11 and analysis of biodegradation mechanisms.

Sulfachloropyridazine (SCP) is a common sulfonamide antibiotic pollutant found in animal excreta. Finding highly efficient degrading bacterial strains is an important measure to reduce SCP antibiotic pollution. Although some strains with degradation capabilities have been screened, the degradation pathways and biotransformation mechanisms of SCP during bacterial growth are still unclear. In this study, a strain capable of efficiently degrading SCP, named Bacillus sp. DLY-11, was isolated from pig manure aerobic compost. Under optimized conditions (5 % Vaccination dose, 51.5 â„ƒ reaction temperature, pH=7.92 and 0.5 g/L MgSO4), this strain was able to degrade 97.7 % of 20 mg/L SCP within 48 h. Through the analysis of nine possible degradation products (including a new product of 1,4-benzoquinone with increased toxicity), three potential biodegradation pathways were proposed. The biodegradation reactions include S-N bond cleavage, dechlorination, hydroxylation, deamination, methylation, sulfur dioxide release, and oxidation reactions. This discovery not only provides a new efficient SCP-degrading bacterial strain but also expands our understanding of the mechanisms of bacterial degradation of SCP, filling a knowledge gap. It offers important reference for the bioremediation of antibiotic pollutants in livestock and poultry farming.

Optimizing mangrove afforestation: Mollusc biodiversity comparisons reveal optimal mudflat-mangrove area ratio.

In recent decades, mangrove wetlands globally have suffered from human activities and climate change, leading to issues like area reduction, degraded ecological functions and declining biodiversity. Restoration efforts, primarily through mangrove afforestation (i.e. mangrove plantation in mudflats), have been widespread, yet they often overlook the significance of unvegetated mudflats. In addition, under the condition that the total area of suitable mudflats is limited, the problem of what is the threshold of mangrove forests and unvegetated mudflats to better protect mangrove biodiversity has not been solved. Therefore, this study conducted a field survey of molluscs in mangrove wetlands in Hainan Island in China and explored the relative importance of mangroves and unvegetated mudflats through taxonomic alpha diversity and functional diversity. The results showed that (1) mollusc abundance of unvegetated mudflats was notably higher than this of mangrove forests, and the species richness, functional richness and functional vulnerability were significantly lower than those of mangrove forests; (2) the abundance and functional vulnerability of molluscs were mainly affected by sediment properties (pH, interstitial water salinity, median diameter, total nitrogen, C/N ratio), while the species richness and functional richness of molluscs were primarily influenced by vegetation structure (plant density); and (3) retaining at least 20% of the unvegetated mudflat area could well protect the biodiversity of mangrove wetlands. To our knowledge, our study is the first to propose the proportion of mangrove forests and unvegetated mudflats on the basis of benthic biodiversity, providing theoretical support and decision-making reference for mangrove protection and restoration.

Hydrothermal synthesized kaolin group lamellar/spongy aluminosilicates for enhanced lead vapor capture.

Developing high-temperature-resistant adsorbents with superior porous properties is crucial for safely disposing of heavy metal-containing solid waste via pyrolysis. We synthesized aluminosilicates hydrothermally and observed that acidic conditions, especially HCl (pH=2.6), favored sponge-like mineral (NC2.6) formation with a specific surface area of 500.31 m²/g and pore volume of 0.986 cm³ /g, while alkaline conditions (pH=12.0) promoted spherical particle growth. NC2.6 exhibited higher adsorption capacity compared to kaolinite and halloysite in the PbCl2 vapor adsorption, reaching a maximum of 137.68 mg/g at 700 â„ƒ (75.91 % stable). We examined the effect of CO2 and H2O on adsorption efficiency and explored the mechanisms using DFT and GCMC simulations. From GCMC results, CO2 negatively impacted PbCl2 adsorption due to competitive adsorption, while H2O increased adsorption content (144.24 mg/g at 700 â„ƒ) by converting PbCl2 into oxides. DFT revealed the presence of CO2 enhanced the adsorption stability of PbCl2 via the formation of covalent bonds between O in CO2 and Pb, and active O on the aluminosilicate surface. H2O increased PbCl2 adsorption energy, as O in H2O occupied an active Al that originally formed a covalent bond with Cl, while the H formed a weak hydrogen bond with this Cl.

Invasibility framework to predict the early colonization of alien Sonneratia in mangrove: Implications for coastal area management.

Invasibility, or an ecosystem's susceptibility to invasion, plays a critical role in managing biological invasions but is challenging to quantify due to its dependence on specific ecosystem variables. This limitation restricts the practical application of this concept in the control of alien species. This study aims to simplify invasibility into measurable components and develop an applicable framework to predict early colonization of alien plants within the coastal mangrove ecosystem. We used the unchanneled path length (UPL), a widely applied hydrological connectivity-related indicator, to assess the accessibility of the mangrove. The enhanced vegetation index (EVI), positively correlated with above-ground biomass, was used to evaluate the potential competitive intensity. Firstly, building on existing studies, we developed a four-quadrant concept model integrating the effects of EVI and UPL on the early colonization of the alien species Sonneratia apetala. Our results revealed significant differences in EVI and UPL values between colonized and uncolonized areas, with colonized regions displaying markedly lower values (P < 0.001). Additionally, logistic regression showed a significant negative association between the probability of successful colonization by S. apetala and both indicators (P < 0.001). These results validate the effectiveness of our conceptual model. Furtherly, we identified four key niche opportunities for exotic species in mangrove: mudflats outside the mangrove forest, tidal creeks, canopy gaps, and unmanaged abandoned aquaculture ponds. Overall, this study provides important insight into the ecological processes of alien S. apetala colonization and practical information for management of coastal areas susceptible to invasion. Additionally, it presents a case study on the practical application of the concept of invasibility in the management of alien species.

A potential slow-release fertilizer based on biogas residue biochar: Nutrient release patterns and synergistic mechanism for improving soil fertility.

The large yield of anaerobic digestates and the suboptimal efficacy of nutrient slow-release severely limit its practical application. To address these issues, a new biochar based fertilizer (MAP@BRC) was developed using biogas residue biochar (BRC) to recover nitrogen and phosphorus from biogas slurry. The nutrient release patterns of MAP@BRC and mechanisms for enhancing soil fertility were studied, and it demonstrated excellent performance, with 59% total nitrogen and 50% total phosphorus nutrient release rates within 28 days. This was attributed to the coupling of the mechanism involving the dissolution of struvite skeletons and the release of biochar pores. Pot experiments showed that crop yield and water productivity were doubled in the MAP@BRC group compared with unfertilized planting. The application of MAP@BRC also improved soil nutrient levels, reduced soil acidification, increased microbial populations, and decreased soil heavy metal pollution risk. The key factors that contributed to the improvement in soil fertility by MAP@BRC were an increase in available nitrogen and the optimization of pH levels in the soil. Overall, MAP@BRC is a safe, slow-release fertilizer that exhibits biochar-fertilizer interactions and synergistic effects. This slow-release fertilizer was prepared by treating a phosphorus-rich biogas slurry with a nitrogen-rich biogas slurry, and it simultaneously addresses problems associated with livestock waste treatment and provides a promising strategy to promote zero-waste agriculture.

Effects of biochar combined with MgO desulfurization waste residue on nitrogen conversion and odor emission in chicken manure composting.

Aim: Chicken manure is known to produce strong odors during aerobic composting, which not only pollutes the surrounding environment but also leads to the loss of valuable nutrients like nitrogen and sulfur, thus reducing the quality of the fertilizer. Methods: In this study, we explored the use of biochar combined with MgO desulfurization waste residue (MDWR) as a novel composting additive. Our approach involved conducting composting tests, characterizing the compost samples, conducting pot experiments, and examining the impact of the additives on nitrogen retention, deodorization, and compost quality. Results: Our findings revealed that the addition of biochar and MDWR significantly reduced ammonia volatilization in chicken manure compost, demonstrating a reduction rate of up to 60.12%. Additionally, the emission of volatile organic compounds (VOCs) from chicken manure compost treated with biochar and MDWR decreased by 44.63% compared to the control group. Conclusions: The composting product treated with both biochar and MDWR (CMB) exhibited a 67.7% increase in total nitrogen (TN) compared to the blank control group, surpassing the other treatment groups and showcasing the synergistic effect of these two additives on nitrogen retention. Moreover, the CMB treatment facilitated the formation of struvite crystals. Furthermore, our pot experiment results demonstrated that the CMB treatment enhanced vegetable yield and quality while reducing nitrate content. These findings highlight the significant impact of MDWR on nitrogen retention, deodorization, and compost quality enhancement, thereby indicating its promising application prospects.

Sustained-release nitrate combined with microbial fuel cell: A novel strategy for PAHs and odor removal from sediment.

Nitrate addition is a biostimulation technique that can improve both the oxidation of acid volatile sulfide (AVS) through autotrophic denitrification and the biodegradation of polycyclic aromatic hydrocarbons (PAHs) via heterotrophic denitrification. However, during the remediation, parts of the dissolved nitrate in the sediment migrates from the sediment to the overlying water, leading to the loss of effective electron acceptor. To overcome this limitation, a combined approached was proposed, which involved nitrocellulose addition and a microbial fuel cell (MFC). Results indicated the nitrate could be slowly released and maintained at a higher concentration over long term. In the combined system, the removal efficiencies of PAHs and AVS were 71.56% and 89.76%, respectively. Furthermore, the voltage attained for the MFC-nitrocellulose treatment was maintained at 146.1 mV on Day 70, which was 5.37 times higher than that of the MFC-calcium nitrate treatment. Sediments with nitrocellulose resulted in lower levels of nitrate and ammonium in the overlying water. Metagenomic results revealed that the combined technology improved the expression of nitrogen-cycling genes. The introduction of MFC inhibited sulfide regeneration during incubation by suppressing the enzyme activity like EC4.4.1.2. The enhanced biostimulation provided potential for in-situ bioremediation utilizing MFC coupled with slow-released nitrate (i.e., nitrocellulose) treatment.

Simultaneous PAHs degradation, odour mitigation and energy harvesting by sediment microbial fuel cell coupled with nitrate-induced biostimulation.

The study investigates a bioremediation process of polycyclic aromatic hydrocarbons (PAHs) removal and odour mitigation combined with energy harvesting. Sediment microbial fuel cells (SMFCs) were constructed with the addition of nitrate in the sediment to simultaneously remove acid-volatile sulphide (AVS) and PAHs. With the combined nitrate-SMFC treatment, over 90% of the AVS was removed from the sediment in 6 weeks of the SMFC operation and a maximum of 94% of AVS removal efficiency was reached at Week 10. The highest removal efficiencies of phenanthrene, pyrene, and benzo[a]pyrene was 93%, 80%, and 69%, respectively. The maximum voltage attained for the combined nitrate-SMFC treatment was 341 mV. Illumina HiSeq sequencing revealed that the autotrophic denitrifiers Thiobacillus are the dominant genus. In electricity generation, both sulphide-oxidation and PAH-oxidation are the possible pathways. Besides, the addition of nitrate stimulated the growth of Pseudomonas which is responsible for the electricity generation and direct biodegradation of the PAHs, indicating a synergistic effect. The developed bioremediation process demonstrated the potential in the in-situ bioremediation process utilizing SMFC combined with nitrate-induced bioremediation.

Multifunctional Nanoparticles Loaded with Vascular Endothelial Growth Factor Inhibitors and MED1 siRNA to Inhibit Breast Cancer Progression by Targeting Tumor-Associated Macrophages and Breast Cancer Cells.

Breast cancer is still threatening many people' lives, hence novel targeted therapies are urgently required to improve the poor outcome of breast cancer patients. Herein, our study aimed to explore the potential of nanoparticles (NPs)-loaded with VEGF inhibitors and MED1 siRNA for treatment of the disorder. PEG and MTC conjugates were synthesized by ion gelation, and equipped with VEGF inhibitor (siV) and MED1 (siD) siRNA (MT/PC/siV-D NPs). The size and morphology of the NPs were detected by TEM. Agarose gel experiment was performed to detect drug encapsulation rate and NPs stability. Zeta potential was assessed by immunofluorescence assay and cell uptake was detected by fluorescence analysis. After cancer cells were treated with NPs or PBS, cell proliferation and invasion were evaluated with VEGF and MED1 expression was detected by Western blot and RT-qPCR analyses. Animal model was conducted to confirm the role of NPs in tumor growth. Results showed that, the MT/PC/siV-D NPs exhibited great stability, drug encapsulation and internalization ability. The combined NPs caused decreased proliferation and invasion of tumor cells, inducing M2 macrophages to re-polarize to M1 type with declined expression of VEGF and MED1. Moreover, the NPs remarkably alleviated breast tumor progression. The multifunctional NPs equipped with EGF inhibitors and MED1 siRNA can inhibit tumor progression by targeting TAMs and cancer cells during breast cancer.

Removal of refractory organics from piggery bio-treatment effluent by the catalytic ozonation process with piggery biogas residue biochar as the catalyst.

After anaerobic-oxic (A/O) treatment, there are often high chromaticity levels in piggery bio-treatment effluents, which still contain a high concentration of refractory organics. This paper describes the use of piggery biogas residue biochar (BioC) to support MnO2 to prepare a catalyst (MnO2/BioC) and examines the effects of catalyst addition, pH and ozone dosage on chromaticity and organic matter degradation in the ozonation process. Three-dimensional fluorescence spectroscopy (3D-EEM) and GC-MS were used to analyse changes in the organic component of the effluent before and after ozonation. The results indicate that the decolorization percentages reached 91.29% and that the UV254 and CODcr removal percentages reached 81.64% and 61.07%, respectively, when the MnO2/BioC catalyst addition amount was 1.0 g·L-1, the pH was 9.0, and the ozone dosage was 0.45 g·L-1. The 3D-EEM analysis results showed that the macromolecular organics mainly consisted of humic acids before treatment, and the removal of humic acid organic matter after treatment had an obvious effect. The GC-MS analysis results showed that the refractory organics were mainly phenols, esters, alcohols and hydrocarbons, and most of the refractory organics were oxidatively degraded after treatment. These results show that ozone catalytic oxidation treatment of piggery bio-treatment effluent can reduce chromaticity and refractory organics.

Influence of reflux ratio on the anaerobic digestion of pig manure in leach beds coupled with continuous stirred tank reactors.

The effect of reflux ratio on the anaerobic mono-digestion of pig manure (PM) in leach beds coupled with continuous stirred tank reactors (CSTRs) has been studied in this work, and contents of volatile fatty acids (VFAs) and biogas yields were determined for three groups of leach bed reactor (LBR) - CSTR systems. The obtained results indicated that the reflux of biogas slurry increased both the pH of the acid-producing phase and acetic acid yield and repeatedly degraded the refractory organic matter in the biogas slurry. The larger reflux ratio increased the inoculation volume and substantially enhanced the mass transfer process. The maximum values of the biogas and methane yields equal to 259.49 and 167.44 mL/g volatile solids, respectively, were achieved at a reflux ratio of 100%. Moreover, the weight of the PM leachate residue was reduced by 94.14%, and the total nutrient content (N + P2O5 + K2O) was relatively high (1.48%), which was suitable for vegetable seedling substrates. In conclusion, during the treatment of PM in LBR-CSTRs, the solid phase remains on the leach bed, and the leachate is supplied to a biogas tank, which effectively increases its stability of operation.

The effect of fermented superphosphate pretreatment and step-feed mode on biological denitrification of piggery wastewater.

Chemical pretreatment can reduce NH3-N levels in piggery wastewater to a certain extent, but the lack of a carbon source for subsequent biological treatment leads to a low denitrification efficiency and poor total nitrogen (TN) removal percentage. Taking superphosphate (SP) pretreatment (SP/Pretreatment) as the control, this research studies the influence of fermented superphosphate (FSP; SP plus a carbon source) pretreatment (FSP/Pretreatment) on biological denitrification in a subsequent biological treatment step. Furthermore, the removal of pollutants under different influent modes is also evaluated. The experimental results show that with the addition of the SP pretreatment, the removal percentage of NH3-N was 52%, and the chemical oxygen demand (COD)/TN ratio increased from 0.36 to 0.71. However, with the addition of the FSP pretreatment, the removal percentage of NH3-N reached 64%, and the COD/TN ratio increased to 2.28. The combination of the FSP pretreatment and a subsequent sequencing batch reactor (SBR) step in the step-feed influent mode resulted in the best denitrification, with a TN removal percentage of 57%. This result was 51% higher than that of the SP/Pretreatment-SBR system, indicating that the addition of the FSP pretreatment improves the biological denitrification of piggery wastewater. After the full treatment process for piggery wastewater, the effluent COD was 57.33 mg·L-1, the NH3-N was 66.32 mg·L-1, and the total phosphorus (TP) was 1.17 mg·L-1, all of which meet the emission standards of the "Fouling Standards for Pollutants in the Livestock Breeding Industry" (GB 18596-2001) (400 mg·L-1 COD, 80 mg·L-1 NH3-N, 8 mg·L-1 TP).