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Interferon (IFN) contributes to the host's antiviral response by inducing IFN-stimulated genes (ISGs). However, their functional targets and the mechanism of action remain elusive. Here, we report that one such ISG, TRIM21, interacts with and degrades the TRPV2 channel in myeloid cells, reducing its expression and providing host protection against viral infections. Moreover, viral infection upregulates TRIM21 in paracrine and autocrine manners, downregulating TRPV2 in neighboring cells to prevent viral spread to uninfected cells. Consistently, the Trim21-/- mice are more susceptible to HSV-1 and VSV infection than the Trim21+/+ littermates, in which viral susceptibility is rescued by inhibition or deletion of TRPV2. Mechanistically, TRIM21 catalyzes the K48-linked ubiquitination of TRPV2 at Lys295. TRPV2K295R is resistant to viral-infection-induced TRIM21-dependent ubiquitination and degradation, promoting viral infection more profoundly than wild-type TRPV2 when reconstituted into Lyz2-Cre;Trpv2fl/fl myeloid cells. These findings characterize targeting the TRIM21-TRPV2 axis as a conducive strategy to control viral spread to bystander cells.
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Ribonucleoproteínas , Canais de Cátion TRPV , Ubiquitinação , Viroses , Animais , Humanos , Camundongos , Regulação para Baixo , Células HEK293 , Herpesvirus Humano 1/fisiologia , Interferons/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/metabolismo , Ribonucleoproteínas/metabolismo , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética , Viroses/metabolismoRESUMO
Rodent damage poses a significant threat to crops, human life, and health. Compared to chemical rodent control, such as placing poisonous baits, it is more economical and environmentally friendly to use physical methods, such as building a rodent-proof wall. This study introduces a method of physically controlling harmful rodents and four methods of calculating the effect of rodents control. To understand the controlling effect of the rodent-proof wall, an investigation was conducted on the Dongting Lake beach and corresponding farmland in the embankment in April and July 2012. Our findings illustrated that the density of the reed vole Microtus fortis in the farmland with rodent-proof walls was 0.52%, significantly lower than that in the farmland without rodent-proof walls (1.76%) after artificial trapping and drug extermination (χ2 = 3.900, P = 0.048). The density of M. fortis that had migrated into the farmland in dikes with a rodent-proof wall decreased by 98.53%, significantly higher than the decrease of density in dikes without a rodent-proof wall (86.61%) (χ2 = 11.060, P = 0.01). The results demonstrated the effectiveness of rodent-proof wall control. Therefore, building a rodent-proof wall should be advocated and vigorously promoted to prevent the migration of rodents into the Dongting Lake area and similar environments, as they cause harm.
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Arvicolinae , Roedores , Animais , Humanos , Lagos , Produtos AgrícolasRESUMO
Introduction: The Yangtze vole (Microtus fortis) is a small herbivorous rodent that usually causes damage to crops and forests in China. Various measures were used to control their population including chemical rodenticides. However, rodenticides may cause secondary damage to the environment and the ecosystem. Therefore, the development of new rodent sterilants is urgent. Considering that some compounds of paper mulberry leaves have been verified that can inhibit the biosynthesis of sexual hormone, we aimed to explore the antifertility effect of paper mulberry leaves on M. fortis. Methods: In this study, voles were divided into three groups including a male group, a female group, and a breeding group, and paper mulberry leaves were added into basal fodder of voles maintained in laboratory, of which the proportion of leaf weight was 50%. In each group, voles were fed with mixed fodder as treatment (BP) and voles were fed with basal fodder as contrast (CK). Results and discussion: After feeding for more than 1 month, the results indicated that paper mulberry leaves attracted voles to feed, but inhibited their growth and reproduction. Since the second week, food intakes of BP have been significantly higher than CK (p< 0.05). However, weights of voles in male and female groups were 72.283 ± 7.394 g and 49.717 ± 2.278 g in the fifth week, and both were significantly reduced compared with their original weight (p< 0.05). Meanwhile, testicular volumes of male voles fed with BP were significantly smaller than CK (former: 318.000 ± 44.654 mm3, latter: 459.339 ± 108.755 mm3); the testosterone level, sperm number, and vitality of BP were obviously weaker than CK. Female uteruses and oophoron of BP grew slower, and the organ coefficients of uterus and oophoron fed BP were both significantly lower than CK (p< 0.05). The first reproduction of BP couple voles spent 45 days, while CK spent only 21 days. These results suggest that paper mulberry leaves could be the potential resource to produce sterilants to control rodent populations by delaying their sexual growth and reproduction. If it was practical, the apparent advantages of paper mulberry are that it is an abundant resource and the inhibitory effect could be effective in both male and female individuals. Our conclusion also supports the transformation of rodent management from lethal management to fertility control, which would be more ecologically friendly to agriculture and the ecosystem.
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Although the research framework of ecological function zoning is complex and diverse, there are not many spatially continuous zoning results, which can be effectively applied to watershed management practices. Ecosystem service bundles and trade-offs can identify interactions among multiple ecosystem services, and achieve better social-ecosystem management when applying to ecological function zoning. Taking the Dongjiang Lake Basin, China, as research area, the study used the InVEST model to investigate the trade-offs and synergies of ecosystem services at township and grid scales, respectively. Then, the study conducted ecological function zoning based on the bundles and trade-off intensity among ecosystem services. The results showed that food production showed extremely significant trade-offs with other services in the two scales, in which the trade-off intensity between food production and water purification was the largest, and the water areas were the hotspots of trade-off intensity. Based on the ecosystem service bundles at the township, combined with the trade-off intensity, the watershed was finally divided into four ecological functional zones, namely, agricultural product supply area (southern part in the study area), economic forestry area (northeast regions in the study area), water supply area (western areas of the study area), and forest conservation area (northern areas in the study area), accounting for 29.27%, 14.63%, 17.07%, and 39.03%, respectively. The study contributed to the ecological function maintenance and sustainable development in Dongjiang Lake Basin and provided an important reference in ecological zoning.
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Ecossistema , Lagos , China , Desenvolvimento Sustentável , Agricultura , Conservação dos Recursos NaturaisRESUMO
The serious ecological damage caused by mining activities cannot be ignored. The use of an environmentally friendly restoration method to rebuild the vegetation and soil environment in the mining area has attracted more and more attention. This paper aims to study soil quality as well as vegetation characteristics of four woody species including Pinus massoniana (P. massoniana), Broussonetia papyrifera (B. papyrifera), Koelreuteria paniculata (K. paniculata), Osmanthus fragrans (O. fragrans), and two herbaceous species including Setaria viridis (S. viridis) and Cynodon dactylon (C. dactylon). In addition, we further clarified the effects of B. papyrifera and K. paniculata on soil nutrients and microbial communities after restoration. The results showed that the vegetation restoration area had better soil quality and plant community diversity, and the woody plants restoration effect were better. Compared with slag, B. papyrifera and K. paniculata remediation could improve soil pH and mitigate heavy metal contamination in mining areas, but was not effective in enhancing Soil Organic Matter (SOM), Total Nitrogen (TN), Total Potassium (TK) and Total Phosphorus (TP). In addition, the abundance and diversity of soil bacterial communities were increased. Of all the study sites, Proteobacteria had the greatest dominance. Vegetation restoration resulted in an increase in the relative abundance of Acidobacteria, while a decrease in Actinobacteria, Cyanobacteria and Firmicutes. With the restoration of vegetation, the increase of pH, the change of TN, SOM, TK, TP and the mitigation of Manganese (Mn) pollution were the main reasons affecting the soil microbial community. This study has great significance for understanding the ecological changes in the mining area after artificially mediated vegetation restoration, including changes in soil environment, plant community and microbial community, and woody plants will be more encouraged for the restoration of manganese mining areas.
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Manganês , Metais Pesados , Manganês/análise , Biodegradação Ambiental , Plantas , Metais Pesados/análise , Bactérias , Solo/química , Microbiologia do SoloRESUMO
Developing broad-spectrum light reactions, effective charge separation, and easily recoverable photocatalysts were considered cost-effective pollution remediation methods. The ZnFe2O4/BC/ZnO composite was prepared to achieve these objectives, where biochar (BC) was used as a conductive channel and ZnFe2O4 as a magnetic substance. Among them, the 0.6-ZBO composite performed the best, with photocatalytic removal of tetracycline (TC) reaching 85.6%. The photocatalytic degradation rated constant of 0.6-ZBO composite was 23.36 × 10-3 min-1, which was 7.6, 4.1, and 2.5 times higher than that of ZnFe2O4/BC, ZnO, and ZnFe2O4/ZnO samples, respectively. According to several characterization data, it was demonstrated that successful Z-scheme heterojunctions were constructed between ZnFe2O4 and ZnO. The 0.6-ZBO complex increased the range of light absorption and strengthened the separation of electron-hole pairs, thus improving the redox ability of the complex. In the different water matrices, the stability of 0.6-ZBO was excellent and its ability to remove TC decreased slightly to about 11% after 5 cycles. This work provided a valuable approach to design a novel and efficient system for degrading organic pollutants in wastewater using magnetic biochar.
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Óxido de Zinco , Catálise , Tetraciclina , Antibacterianos , LuzRESUMO
Photocatalysis, as a novel technique, has been widely used for antibiotic pollution remediation in wastewater. In the processes of degradation and removal of antibiotics, the impact of photocatalysts on microenvironment is very important but remains poorly understood. In the present study, the effect of typical photocatalyst g-C3N4 (Graphitic carbon nitride) on microbial community was investigated in two sediment types (riverbed sediment and pig-farm sediment) polluted by tetracycline (TC) in central southern China. The riverbed sediment and pig farm sediment samples were respectively exposed to g-C3N4 (25, 75, 125 mgâ kg-1) and TC (60, 120, 180 mgâ L-1) treatments alone or combination for 30 days, respectively. The bacterial community and antibiotic resistance genes (ARGs) of the treated sediments were analyzed by Illumina sequencing and metagenomic sequencing. Studies had shown that: TC, g-C3N4, and TC/g-C3N4 have significant effects on the changes of microbial communities and components in riverbed sediment, but they do not exist in pig farm sediment. The most alterations of microbial taxa were Acidobacteriota, Actinobacteriota, and Desulfobacterota in riverbed sediment, and Elusimicrobiota in the pig farm sediment under various treatments. Through network analysis, it was found that the distribution of microorganisms in the pig farm sediment is more complex and more stable. The addition of g-C3N4 reduced the absolute abundance of ARGs in the two examined sediments, but not significantly changed their relative abundance of ARGs. The g-C3N4 application was beneficial to the removal of TC residues and to the prevention of the generation and transmission of ARGs in sediments. Our results suggested that g-C3N4 was a suitable photocatalyst with excellent application prospect for the removal of TC residues and the control of ARGs in environment.
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Biochar had been widely used to improve the activity of photocatalysts, the biochar-based photocatalysts had more potential for environmental pollution remediation, but their effect on the sediment remained unknown. To understand these, the typical photocatalyst g-C3N4 was modified by biochar to develop g-C3N4/biochar with enhanced photocatalytic ability. Riverbed sediment was exposed to g-C3N4 and g-C3N4/biochar respectively for 30 days, and Illumina sequencing was utilized to examine the changes in the bacterial community in the sediment. The results showed that in riverbed sediment, g-C3N4 exposure had a concentration-dependent effect on the diversity of bacteria, while g-C3N4/biochar exposure had a slight influence on the bacterial diversity and the diversity almost maintained stable with different g-C3N4/biochar concentration. The application of g-C3N4 exhibited an inhibition influence on the growth of Acidobacteria, Gemmatimonadetes, and Rokubacteria in sediment, whose relative abundance increased when g-C3N4 was 25 mg/kg, and then decreased when g-C3N4 beyond this concentration. The presence of g-C3N4/biochar increased the relative abundance of Cyanobacteria in sediment and showed no obvious impact on other dominant phyla. Both g-C3N4 and g-C3N4/biochar could alter the levels of TP, NN, and AN in the sediment, but the magnitude of the changes of these physicochemical factors caused by g-C3N4/biochar was much smaller than those caused by g-C3N4. In addition, the complexity of the bacterial community network was reduced in a high concentration of g-C3N4, while it remained stable with different concentrations of g-C3N4/biochar treatments. Totally, this study demonstrated that, compared to g-C3N4, g-C3N4/biochar was able to maintain the relative stability of the bacterial community in riverbed sediment and mitigate the negative effects of photocatalysts to some extent, making biochar an ecological remediation agent with great potential for application.
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Carvão Vegetal , Recuperação e Remediação Ambiental , Carvão Vegetal/farmacologia , BactériasRESUMO
Heavy metal resistant bacteria play an important role in the metal biogeochemical cycle in soil, but the benefits of microbial oxidation for plants and soil have not been well-documented. The purpose of this study was to explore the contribution of two Bacillus spp. to alleviate the antimony (Sb) toxicity in plants, and, then, to propose a bioremediation method for Sb contaminated soil, which is characterized by environmental protection, high efficiency, and low cost. This study explored the effects of Bacillus cereus HM5 and Bacillus thuringiensis HM7 inoculation on Broussonetia papyrifera and soil were evaluated under controlled Sb stressed conditions (0 and 100 mmol/L, antimony slag) through a pot experiment. The results show that the total root length, root volume, tips, forks, crossings, and root activities of B. papyrifera with inoculation are higher than those of the control group, and the strains promote the plant absorption of Sb from the soil environment. Especially in the antimony slag treatment group, B. cereus HM5 had the most significant effect on root promotion and promoting the absorption of Sb by B. papyrifera. Compared with the control group, the total root length, root volume, tips, forks, crossings, and root activities increased by 64.54, 70.06, 70.04, 78.15, 97.73, and 12.95%, respectively. The absorption of Sb by root, stem, and leaf increased by 265.12, 250.00, and 211.54%, compared with the control group, respectively. Besides, both B. cereus HM5 and B. thuringiensis HM7 reduce the content of malondialdehyde, proline, and soluble sugars in plant leaves, keeping the antioxidant enzyme activity of B. papyrifera at a low level, and alleviating lipid peroxidation. Principal component analysis (PCA) shows that both B. cereus HM5 and B. thuringiensis HM7 are beneficial to the maintenance of plant root functions and the improvement of the soil environment, thereby alleviating the toxicity of Sb. Therefore, B. cereus HM5 and B. thuringiensis HM7 in phytoremediation with B. papyrifera is a promising inoculant used for bacteria-assisted phytoremediation on Sb contaminated sites.
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Photocatalysts have been widely prepared and used in wastewater treatment. Although the influence of photocatalyst application on survival and activity of organisms has been examined, its impact on composition and diversity of microbial community is not fully understood. In this study, the impact of photocatalyst g-C3N4 (Graphitic carbon nitride) on microbial communities in riverbed sediments polluted by antibiotic tetracycline (TC) was investigated. The sediment samples collected from the Xiangjiang River of China were exposed to different concentrations of TC, g-C3N4 and TC/g-C3N4 and the bacterial community were analyzed by Illumina sequencing. The results showed that the dominant bacterial phyla were Acidobacteriota, Proteobacteria, Actinobacteriota, and Chloroflexi in the study site. When compared to the control treatments, the application of TC, g-C3N4 and TC/g-C3N4 exhibited distinguishable effects on bacterial community structure in sediments. The presence of TC had greater influence on bacterial composition, while g-C3N4 and TC/g-C3N4 had less influence on bacteria. The diversity and richness of microorganisms in sediment increased under g-C3N4 application and reached the highest values when g-C3N4 was 75 mg/kg. The photocatalyst g-C3N4 restored bacterial community diversity affected by TC, reduced the TC residues in aquatic environment, and eliminated the side effects of TC application in sediments. Our study indicated that g-C3N4 was an environmentally friendly photocatalyst with lightly negative effects on microbial community in riverbed sediments, and could be used for effective remediation of TC-contaminated environments.
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Bactérias , Rios , Antibacterianos/toxicidade , Biodiversidade , Sedimentos Geológicos/química , Rios/química , TetraciclinasRESUMO
For highly efficient photocatalytic remediation of organic pollutants, broad-spectrum light response and effective charge separation are two key goals. To achieve these goals, a novel biochar (BC) modified PbMoO4 composite catalyst was successfully synthesized in situ by combining coprecipitation with pyrolysis treatment of poplar sawdust and the technical feasibility of degradation of tetracycline (TC) with compound photocatalyst prepared from recovered agricultural and forestry residues was preliminarily demonstrated. The characterization demonstrated that the presence of BC narrowed the bandgap, enhanced visible light absorption as well as facilitated charge separation. Three composites (with the mass ratio of PbMoO4 to BC = 1:4; 1:1; and 4:1, respectively) displayed higher activity than pure PbMoO4. The results showed that the composite with the PbMoO4 to BC ratio of 1:4 exhibited the best photocatalytic activity, for 150 mg L-1 TC the removal rate was 61.0%, and the rate constant was 8.1 × 10-3 min-1, while the photocatalytic activity of PbMoO4 was 26.0% and 3.9 × 10-3 min-1. The reactions in the presence of radical quenchers indicated that holes (h+) and superoxide radicals (O2-) were the dominant active species for photodegradation. In different water matrices, for 150 mg L-1 TC solution the photocatalytic activity of optimal photocatalyst decreased as follows: ultrapure water > artificial sewage > farm sewage > municipal sewage. Moreover, the catalyst exhibited good stability over five cycles. Therefore, BC doped PbMoO4 provides a useful strategy for improving the photocatalytic ability of PbMoO4-based photocatalysts and offers a promising method for water purification.
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Carvão Vegetal , Tetraciclina , Catálise , LuzRESUMO
BACKGROUND: Cultivated tea is one of the most important economic and ecological trees distributed worldwide. Cultivated tea suffer from long-term targeted selection of traits and overexploitation of habitats by human beings, which may have changed its genetic structure. The chloroplast is an organelle with a conserved cyclic genomic structure, and it can help us better understand the evolutionary relationship of Camellia plants. RESULTS: We conducted comparative and evolutionary analyses on cultivated tea and wild tea, and we detected the evolutionary characteristics of cultivated tea. The chloroplast genome sizes of cultivated tea were slightly different, ranging from 157,025 to 157,100 bp. In addition, the cultivated species were more conserved than the wild species, in terms of the genome length, gene number, gene arrangement and GC content. However, comparing Camellia sinensis var. sinensis and Camellia sinensis var. assamica with their cultivars, the IR length variation was approximately 20 bp and 30 bp, respectively. The nucleotide diversity of 14 sequences in cultivated tea was higher than that in wild tea. Detailed analysis on the genomic variation and evolution of Camellia sinensis var. sinensis cultivars revealed 67 single nucleotide polymorphisms (SNPs), 46 insertions/deletions (indels), and 16 protein coding genes with nucleotide substitutions, while Camellia sinensis var. assamica cultivars revealed 4 indels. In cultivated tea, the most variable gene was ycf1. The largest number of nucleotide substitutions, five amino acids exhibited site-specific selection, and a 9 bp sequence insertion were found in the Camellia sinensis var. sinensis cultivars. In addition, phylogenetic relationship in the ycf1 tree suggested that the ycf1 gene has diverged in cultivated tea. Because C. sinensis var. sinensis and its cultivated species were not tightly clustered. CONCLUSIONS: The cultivated species were more conserved than the wild species in terms of architecture and linear sequence order. The variation of the chloroplast genome in cultivated tea was mainly manifested in the nucleotide polymorphisms and sequence insertions. These results provided evidence regarding the influence of human activities on tea.
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Camellia sinensis , Camellia , Genoma de Cloroplastos , Camellia/genética , Camellia sinensis/genética , Genoma de Cloroplastos/genética , Humanos , Filogenia , CháRESUMO
Broussonetia papyrifera is a widely distributed economic tree species, and it is also a pioneer species in adverse environments. In order to investigate the growth and adaptation mechanism of B. papyrifera under cadmium (Cd) contaminated soil, potted experiments were used with six-month treatments to study Cd enrichment and the transportation, morphological and physiological characteristics of B. papyrifera tissues. The results showed that Cd mainly accumulated in the root when the Cd concentration was high (14.71 mg/kg), and the root biomass was significantly reduced by Cd stress although Cd promoted the growth of seedlings. The bioconcentration factors (BCF) increased with the increase in Cd concentration, and reached the maximum value of 0.21 at 14.71 mg/kg. On the contrary, translocation factor (TF) decreased significantly at 8.28-14.71 mg/kg Cd concentration. Cd not only led to the loose arrangement of the xylem vessels of leaves, but also changed the chlorophyll content. However, B. papyrifera could synthesize organic solutes such as soluble protein, soluble sugar and proline to reduce the intracellular osmotic potential. Our study proved that B. papyrifera has good tolerance to Cd stress and is a pioneer tree species for soil and ecological environment restoration.
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Two novel actinobacteria, designated strains GY16T and T44T, were isolated from the leaves and rhizosphere soil of Broussonetia papyrifera, respectively. A polyphasic approach was used for determining their taxonomic position. Results of 16S rRNA gene sequence analysis indicated that strain GY16T exhibited highest similarities to Streptomyces cinereoruber subsp. fructofermentans CGMCC 4.1593T (98.82â%), Streptomyces deccanensis KCTC 19241T (98.76â%), Streptomyces scabiei NRRL B-16523T (98.69â%), Streptomyces europaeiscabiei KACC 20186T (98.69â%) and Streptomyces rishiriensis NBRC 13407T (98.69â%), and strain T44T showed 99.2, 99.1, 99.1 and <98.7â% sequence similarities to Streptomyces filipinensis CGMCC 4.1452T, Streptomyces achromogenes subsp. achromogenes DSM 40028T, Streptomyces durhamensis DSM 40539T and other Streptomyces species, respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain GY16T formed an independent subclade, which indicated that strain GY16T should belong to a potential novel species; and strain T44T was closely related to S. filipinensis CGMCC 4.1452T, S. achromogenes subsp. achromogenes DSM 40028T, S. durhamensis DSM 40539T and S. yokosukanensis DSM 40224T. However, the multilocus sequence analysis evolutionary distance, average nucleotide identity and DNA-DNA hybridization values between closely related relatives were far from the species-level thresholds. In addition, phenotypic and chemotaxonomic characteristics further confirmed that strains GY16T and T44T belonged to two distinct species. Based on these results, it is concluded that the isolated strains represent novel species within the genus Streptomyces, for which the names Streptomyces phaeolivaceus sp. nov. (type strain GY16T=CICC 24807T=KCTC 49326T) and Streptomyces broussonetiae sp. nov. (type strain T44T=CICC 24819T=JCM 33918T) are proposed.
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Broussonetia/microbiologia , Filogenia , Microbiologia do Solo , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Folhas de Planta , RNA Ribossômico 16S/genética , Rizosfera , Análise de Sequência de DNA , Streptomyces/isolamento & purificaçãoRESUMO
Microorganisms play a significant part in detoxifying and immobilizing excessive metals. The present research isolated a strain (HM7) with high Mn(II) tolerance from Mn(II)-contaminated soil samples. The 16S rDNA sequence analysis showed that HM7 had a 99% similarity to Bacillus thuringiensis, which can survive under a high concentration 4,000 mg/L of Mn(II), and the highest removal rate was up to 95.04% at the concentration of 400 mg/L. The highest Mn(II) removal rate was detected at the contact time 72 h, temperature 30 °C, and pH 5.0, while the differences in strain growth and Mn(II) removal rate among different inoculation doses were insignificant. Scanning electron microscopy indicated B. thuringiensis HM7 cells appeared irregular and cracked under Mn(II) stress. Fourier transform infrared exhibited that functional groups like carboxyl, hydroxyl, amino, sulfhydryl groups, and amide bands might take part in the complexation of Mn(II). In addition, HM7 suggested the ability of indoleacetic acid production, siderophore production, and P' solubilization potential. Therefore, HM7 might have a potential to promote metal absorption by changing the form of heavy metals, and the experiments supported the application of B. thuringiensis HM7 as a biological adsorbent in Mn(II) contaminated environment remediation.
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In the present work, a series of magnetically separable Fe3O4/g-C3N4/MoO3 nanocomposite catalysts were prepared. The as-prepared catalysts were characterized by XRD, EDX, TEM, FT-IR, UV-Vis DRS, TGA, PL, BET and VSM. The photocatalytic activity of photocatalytic materials was evaluated by catalytic degradation of tetracycline solution under visible light irradiation. Furthermore, the influences of weight percent of MoO3 and scavengers of the reactive species on the degradation activity were investigated. The results showed that the Fe3O4/g-C3N4/MoO3 (30%) nanocomposites exhibited highest removal ability for TC, 94% TC was removed during the treatment. Photocatalytic activity of Fe3O4/g-C3N4/MoO3 (30%) was about 6.9, 5, and 19.9-fold higher than those of the MoO3, g-C3N4, and Fe3O4/g-C3N4 samples, respectively. The excellent photocatalytic performance was mainly attributed to the Z-scheme structure formed between MoO3 and g-C3N4, which enhanced the efficient separation of the electron-hole and sufficient utilization charge carriers for generating active radials. The highly improved activity was also partially beneficial from the increase in adsorption of the photocatalysts in visible range due to the combinaion of Fe3O4. Superoxide ions (·O2-) was the primary reactive species for the photocatalytic degradation of TC, as degradation rate were decreased to 6% in solution containing benzoquinone (BQ). Data indicate that the novel Fe3O4/g-C3N4/MoO3 was favorable for the degradation of high concentrations of tetracycline in water.
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Óxido Ferroso-Férrico/química , Grafite/química , Molibdênio/química , Nanocompostos/química , Compostos de Nitrogênio/química , Óxidos/química , Processos Fotoquímicos , Tetraciclina/química , Água/química , Catálise , Luz , Imãs/química , Tetraciclina/isolamento & purificação , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificaçãoRESUMO
Combining phytoremediation plants and microorganisms is a promising method of remediating heavy metal contaminated soil. In this study, two manganese-tolerant strains were isolated from Mn slag and identified as Bacillus cereus HM5 and Bacillus thuringiensis HM7. These two Bacillus spp. have the ability to dissolve phosphorus, produce IAA and iron carrier. A pot experiment of Broussonetia papyrifera was conducted to explore potential of B. cereus HM5 and B. thuringiensis HM7 to improve effect of remedying Mn pollution by B. papyrifera. The strains were inoculated under different Mn treated (5 mmol/L, 50 mmol/L, Mn slag) respectively and the growth, root structure, root activity, physiological and biochemical characteristics of the leaves and accumulation of Mn for B. papyrifera were determinated. The effects of the soil environment to remediation were observed, the results showed that the biomass, total root length, surface area, crossings, tips, forks and root activity of B. papyrifera with inoculated strain were higher than those of the control group. The inoculation of these two Bacillus spp. increased the absorption of Mn by B. papyrifera and the concentration of Mn in the aerial parts of plants, indicating that the two strains could promote the growth of B. papyrifera and the accumulation of Mn. In addition, microbes reduced malonaldehyde content and the activities of antioxidant enzymes in leaves, suggesting that the two Bacillus spp. reduced Mn-induced oxidative stress. The principal component analysis showed that the added Bacillus strain prefer to promote plant root function maintenance and improve soil environment, rather than direct adsorption of heavy metals. These observations indicated that B. cereus HM5 and B. thuringiensis HM7 were valuable microorganisms, which could improve the remediating efficiency of B. papyrifera under Mn-contaminated soil.
Assuntos
Biodegradação Ambiental , Broussonetia/fisiologia , Manganês/metabolismo , Bacillus/fisiologia , Bacillus cereus , Biomassa , Broussonetia/microbiologia , Manganês/análise , Metais Pesados/análise , Desenvolvimento Vegetal , Folhas de Planta/química , Raízes de Plantas/química , Solo/química , Poluentes do Solo/análiseRESUMO
Norfloxacin (NOF) is an environmentally harmful and ubiquitous aquatic pollutant with extensive production and application. In this study, a novel composition named carbon-based composite photocatalytic material of zinc oxide and zinc sulphide (ZnO/ZnS@BC) was successfully obtained by the impregnation-roasting method to remove NOF under UV-light. Scanning electron microscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and energy dispersive spectrometer characterised the composition. ZnO/ZnS was successfully decorated on the surface of biochar (BC). The pH, the ZnSO4/PS ratio, and ions and quenchers, were investigated. High removal efficiency was obtained with a pH of 7 and a ZnSO4/PS ratio of 1:1, and the removal ratio of NOF reached 95% within three hours; the adsorption and degradation ratios reached 46% and 49%, respectively. Fe2+ promoted the degradation of NOF, whereas other ions inhibited it, with NO3- showing the strongest inhibitory effect. Three reactive species (tert-butanol, quinone, and ammonium oxala) were identified in the catalytic system. The decreasing order of the contribution of each reactive species was: O2- > ·OH- > h+. Additionally, a recycling experiment demonstrated the stability of the catalyst; the catalytic degradation ratio of NOF reached 78% after five successive runs. Therefore, ZnO/ZnS@BC possessed strong adsorption capacity and high ultraviolet photocatalysis ability.
RESUMO
Lack of complete genomic information concerning Vicia sepium (Fabaceae: Fabeae) precludes investigations of evolution and populational diversity of this perennial high-protein forage plant suitable for cultivation in extreme conditions. Here, we present the complete and annotated chloroplast genome of this important wild resource plant. V. sepium chloroplast genome includes 76 protein-coding genes, 29 tRNA genes, 4 rRNA genes, and 1 pseudogene. Its 124,095 bp sequence has a loss of one inverted repeat (IR). The GC content of the whole genome, the protein-coding, intron, tRNA, rRNA, and intergenic spacer regions was 35.0%, 36.7%, 34.6%, 52.3%, 54.2%, and 29.2%, respectively. Comparative analyses with plastids from related genera belonging to Fabeae demonstrated that the greatest variation in the V. sepium genome length occurred in protein-coding regions. In these regions, some genes and introns were lost or gained; for example, ycf4, clpP intron, and rpl16 intron deletions and rpl20 and ORF292 insertions were observed. Twelve highly divergent regions, 66 simple sequence repeats (SSRs) and 27 repeat sequences were also found in these regions. Detailed evolutionary rate analysis of protein-coding genes showed that Vicia species exhibit additional interesting characteristics including positive selection of ccsA, clpP, rpl32, rpl33, rpoC1, rps15, rps2, rps4, and rps7, and the evolutionary rates of atpA, accD, and rps2 in Vicia are significantly accelerated. These genes are important candidate genes for understanding the evolutionary strategies of Vicia and other genera in Fabeae. The phylogenetic analysis showed that Vicia and Lens are included in the same clade and that Vicia is paraphyletic. These results provide evidence regarding the evolutionary history of the chloroplast genome.