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Jiaosu, also called as fermented fruit and vegetable juices, is becoming an increasingly popular health food, especially in East Asian markets. Watermelon, cantaloupe and orange were used as the raw materials to produce five kinds Jiaosu with natural fermentation, including single source Jiaosu and mixed jiaosu. Then the composition and antioxidant capacity were determined. All Jiaosu appear brown and different Jiaosu vary greatly. The pH of five kinds Jiaosu range from 3.06 to 4.55. Between the five kinds Jiaosu, orange Jiaosu is the highest in total protein (9.46 ± 0.41 mg/ml), total phenol (0.32 ± 0.01 μg/ml) and alcohol (56.51 ± 0.03 μg/ml). All Jiaosu have strong antioxidant capacity and watermelon Jiaosu shows the strongest antioxidant capacity. The antioxidant capacity of five kinds Jiaosu determined by FRAP assay is significantly correlated with the total protein content and total phenol content, respectively. The results indicated the raw materials had a decisive effect on the components and antioxidant capacity of Jiaosu. [ABSTRACT FROM AUTHOR]

Lupinus is one of the most geographically widespread genera. It can be divided into New World and Old World Lupinus species according to the geographical distribution of its members. However, there are relatively few studies on their genetic differences, especially regarding the taxonomy and geographical evolutionary history of New World species. Here, we conducted comparative, phylogenetic, and evolution analysis between one New World and five Old World Lupinus species based on their complete chloroplast genomes. Compared with the Old World species, the chloroplast genome of L. westianus in the New World was more variable, showing the deletion of the pseudogene ycf1 and two rps12 gene introns, the 20 kb inversion, the higher number of repeated sequences, the larger genome size, and the lower GC content. Phylogenetic analysis indicated that the genetic relationship between the New World species L. westianus and the Old World species L. albus was closer than to the rest. Evolutionary analysis confirmed that the matK and ycf1 genes were under positive selection, and rpoA, accD, and rpoC2 genes have site-specific selection in L. westianus, which might be related to adaptive evolution. Therefore, our finding would provide genetic information for the evolutionary history and taxonomy of Lupinus species. [ABSTRACT FROM AUTHOR]

Microorganisms play an important role in immobilizing and detoxifying excessive Mn; however, there is so far a lack of sufficient information concerning highly Mn(II)-tolerant bacteria. The present study was conducted to analyze the bio-sorption characteristics of a strain (HM8) isolated from manganese ore wastes. Analytical data from the 16S rDNA sequence determination showed that the species, HM8, had a 99% similarity to Ralstonia pickettii. Results from the designed physiological, biochemical and isothermal adsorption tests indicated that HM8 did not only grow well at a Mn(II) concentration level of 10,000 mg/L but also removed 1,002.83 mg/L of Mn(II) from the bulk solution of the culture, showing that the isolated strain possessed strong capabilities to tolerate and remove Mn(II). In the isothermal bio-sorption experiments performed to investigate the effects of relevant factors on Mn(II) sorption, the highest Mn(II) removal rate was obtained at the contact time 72 h, temperature 40°C, and pH 6.0, while the differences in both strain growth and Mn(II) removal rate between different inoculated HM8 doses were found to be insignificant within the tested range. Scanning electron microscopy showed that, under Mn(II) stress, HM8 cells appeared irregular and cracked, with apparent wrinkles on the surface. The peaks in the Fourier transform infrared spectra showed that hydroxyl and carboxyl groups were the main functional groups for Mn(II) adsorption. The experimental data supported the practical application of HM8 as a biological adsorbent for remediation of heavily Mn contaminated sites. [ABSTRACT FROM AUTHOR]

Key message: JrVHAG1 is an important candidate gene for plant osmotic tolerance regulation. Abstract: Vacuolar H-ATPase (V-ATPase) is important for plant responses to abiotic stress; the G subunit is a vital part of V-ATPase. In this study, a G subunit of V-ATPase was cloned from Juglans regia ( JrVHAG1) and functionally characterized. JrVHAG1 transcription was induced by mannitol that increasing 17.88-fold in the root at 12 h and 19.16-fold in the leaf at 96 h compared to that under control conditions. JrVHAG1 was overexpressed in Arabidopsis and three lines (G2, G6, and G9) with highest expression levels were selected for analysis. The results showed that under normal conditions, the transgenic and wild-type (WT) plants displayed similar germination, biomass accumulation, reactive oxygen species (ROS) level, and physiological index. However, when treated with mannitol, the fresh weight, root length, water-holding ability, and V-ATPase, superoxide dismutase, and peroxidase activity of G2, G6, and G9 were significantly higher than those of WT. In contrast, the ROS and cell damage levels of the transgenic seedlings were lower than those of WT. Furthermore, the transcription levels of V-ATPase subunits, ABF, DREB, and NAC transcription factors (TFs), all of which are factors of ABA signaling pathway, were much higher in JrVHAG1 transgenic plants than those in WT. The positive induction of JrVHAG1 gene under abscisic acid (ABA) treatments in root and leaf tissues indicates that overexpression of JrVHAG1 improves plant tolerance to osmotic stress relating to the ABA signaling pathway, which is transcriptionally activated by ABF, DREB, and NAC TFs, and correlated to ROS scavenging and V-ATPase activity. [ABSTRACT FROM AUTHOR]

Rodent pests severely damage agricultural crops. Outbreak risk models of rodent pests often do not include sufficient information regarding geographic variation. Habitat plays an important role in rodent-pest outbreak risk, and more information about the relationship between habitat and crop protection is urgently needed. The goal of the present study was to provide an outbreak risk map for the Dongting Lake region and to understand the relationship between rodent-pest outbreak variation and habitat distribution. The main rodent pests in the Dongting Lake region are Yangtze voles ( Microtus fortis). These pests cause massive damage in outbreak years, most notably in 2007. Habitat evaluation and ecological details were obtained by analyzing the correlation between habitat suitability and outbreak risk, as indicated by population density and historical events. For the source-sink population, 96.18% of Yangtze vole disaster regions were covered by a 10-km buffer zone of suitable habitat in 2007. Historical outbreak frequency and peak population density were significantly correlated with the proportion of land covered by suitable habitat ( r = 0.68, P = 0.04 and r = 0.76, P = 0.03, respectively). The Yangtze vole population tends to migrate approximately 10 km in outbreak years. Here, we propose a practical method for habitat evaluation that can be used to create integrated pest management plans for rodent pests when combined with basic information on the biology, ecology and behavior of the target species. [ABSTRACT FROM AUTHOR]

In this article, we study the limit set of trajectory in three-dimensional quasi-homogeneous system. For the trajectory which is close to a singular curve, we show that either it approaches a fixed point or infinity, or it oscillates. Moreover, an oscillating example is given. The behaviour of trajectory which is near a closed orbit is also studied. At the end, we classify the integral manifolds of the system with isolated singularities. [ABSTRACT FROM PUBLISHER]

In this paper, we study the number of limit cycles that bifurcate from the periodic orbits of a cubic reversible isochronous center under cubic perturbations. It is proved that in this situation the least upper bound for the number of zeros (taking into account the multiplicity) of the Abelian integral associated with the system is equal to four. Moreover, for each k = 0, 1, ..., 4, there are perturbations that give rise to exactly k limit cycles bifurcating from the period annulus. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we study the projective vector field of a three-dimensional quasi-homogeneous system with weight and degree , . Projective vector fields of this kind are classified into two types. For one type, has no closed orbit and at most eight singularities, which lead to a global topology of the three-dimensional system. For the other type, has at most ten singularities. In addition, we show a relationship between and a Lienard system of this type. For both of them we obtain some conditions for the existence of limit cycles. [Copyright &y& Elsevier]

Spatial and quantitative assessments of water yield services in watershed ecosystems are necessary for water resource management and improved water ecological protection. In this study, we used the InVEST model to estimate regional water yield in the Dongjiang Lake Basin in China. Moreover, we designed six scenarios to explore the impacts of climate and land use/land cover (LULC) changes on regional water yield and quantitatively determined the dominant mechanisms of water yield services. The results are expected to provide an important theoretical reference for future spatial planning and improvements of ecological service functions at the water source site. We found that (1) under the time series analysis, the water yield changes of the Dongjiang Lake Basin showed an initial decrease followed by an increase. Spatially, water yield also decreased from the lake area to the surrounding region. (2) Climate change exerted a more significant impact on water yield changes, contributing more than 98.26% to the water yield variability in the basin. In contrast, LULC had a much smaller influence, contributing only 1.74 %. (3) The spatial distribution pattern of water yield services in the watershed was more vulnerable to LULC changes. In particular, the expansion of built-up land is expected to increase the depth of regional water yield and alter its distribution, but it also increases the risk of waterlogging. Therefore, future development in the basin must consider the protection of ecological spaces and maintain the stability of the regional water yield function. [ABSTRACT FROM AUTHOR]

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. • B. cereus HM5/ B. thuringiensis HM7 improved the accumulation of Mn by B. papyrifera. • B. cereus HM5 and B. thuringiensis HM7 could reduce oxidative stress induced by Mn. • The strains promoted the growth of plant root system and improved soil environment. [ABSTRACT FROM AUTHOR]

Spectral reflectance distortions caused by terrain and solar illumination seriously reduce the accuracy of mapping forest carbon density, especially in mountainous regions. Many models have been developed for mitigating or eliminating the terrain effects on the quality of remote sensing images in hilly and mountainous areas. However, these models usually use global parameters, which may lead to overcorrections for regions with poor illumination and steep slopes. In this study, we present a local parameter estimation (LPE) method based on a pixel-moving window for topographic correction (TC), which can be considered as a general optimization framework for most semiempirical TC models. We set seven kernel sizes for the presented framework, which are 15 pixels, 25 pixels, 50 pixels, 100 pixels, 250 pixels, 500 pixels, and 1000 pixels, respectively. The proposed method was then applied to four traditional TC models, Minnaert (MIN), C Correction (CC), Sun Canopy Sensor + C (SCSC) and Statistical Empirical Correction (SEC), to form four new TC models. These new models were used to estimate forest carbon density of a mountainous area in Southern China using field plot data and a Landsat 8 image. Four evaluation methods, including correlation analysis, the stability of land covers, comparison of reflectance between sunlit and shaded slopes, and accuracy assessment of forest carbon density, were employed to evaluate the contributions of moving window sizes, and assess the performance of the TC models for forest carbon density estimation. The results show that the four TC models with LPE perform much better than the traditional TC models in reducing the topographic effects and improving the estimation accuracy of forest carbon density for the study area. Among the traditional TC models, SEC performs slightly better than SCSC, CC, and MIN. Therefore, the SEC-based model with LPE, that is, LPE-SEC, gets greater R2 and smaller relative RMSE values in estimating forest carbon density than other models. Moreover, all the means of the predicted forest carbon density values fall in the confidence interval of the validation data at a significant level of 0.05. Overall, this study implies that the proposed method with LPE provides great potential to improve the performance of TC and forest carbon density estimation for the study area. It is expected that the improved TC method can be applied to other mountainous areas to improve the quality of remotely sensed images. [ABSTRACT FROM AUTHOR]

Thiourea-dioxide–reduced magnetic graphene oxide (TDMGO) was successfully prepared as an efficient adsorbent for the removal of tetracycline (TC) from aqueous solutions via strong adsorptive interactions. The composite was characterized by SEM, TEM, EDS, TGA, FT-IR, XPS, XRD and VSM. The effects of variables such as the pH, TC concentration, and temperature were successfully analyzed. The kinetics and isothermal parameters were described well by pseudo-second-order and Langmuir isotherm models, respectively, and the maximum adsorption capacity ( q m ) of TDMGO for TC calculated from the Langmuir isotherm was 1233 mg/g at 313 K. The removal of TC onto TDMGO, as indicated by the thermodynamic parameters, was spontaneous and endothermic. The removal performance was slightly affected by the solution pH. The presence of NaCl in the solution facilitated TC adsorption, and the optimum adsorption capacity was obtained when the NaCl concentration was >0.001 M. The adsorption capacity decreased slightly with increasing humic acid concentration. In addition, the adsorbent could be regenerated and reused. Based on these results, TDMGO is a promising adsorbent for the efficient removal of TC antibiotics from aquatic environments for pollution treatment. [ABSTRACT FROM AUTHOR]

A novel PbMoO4@MBC (MBL-2) magnetic heterojunction photocatalyst was prepared by the successful loading of Fe3O4 with PbMoO4 onto the highly conductive BC surface through the integration of co-precipitation and pyrolysis. Using advanced characterization methods could reveal the composition, morphology, and optoelectronic properties of the material. The results showed that using BC as the electron transfer interface provided a pathway for charge transfer between Fe3O4 and PbMoO4, and importantly, the PbMoO4@MBC (MBL-2) nanocomposite had a large specific surface area, excellent magnetic response, high light absorption capacity for efficient carrier separation, and thus the photocatalytic activity was high. The degradation rate of MBL-2 for TC under visible light was as high as 89%. More importantly, PbMoO4@MBC (MBL-2) possessed good stability and reusability. The Z-scheme electron transfer pathway for improved photocatalytic performance was proposed by radical capture experiments and electron spin resonance (ESR) measurement analysis. [ABSTRACT FROM AUTHOR]

Water area and waterweed coverage are the key environmental factors for ecological breeding of Eriocheir sinensis in ponds. In order to explore the effects of above two factors on the growth of E. sinensis, three groups of experiments were set up: low coverage small area (C1S1), high coverage small area (C2S1), and high coverage large area (C2S2), and water environmental factors and the growth of E. sinensis were monitored. The results showed that the dissolved oxygen of ponds with different waterweed coverage was significantly different (p < 0.05), and the phosphate in ponds changed significantly from July to October (p < 0.05). The correlation analysis showed that NH3-N and pH were significantly positively correlated (p < 0.05). At the same time, there was a significant negative correlation between NH3-N and DO, H3PO4 and pH (p < 0.05). Further analysis of the relationship between surface area, waterweed coverage and environmental factors revealed that the surface area and waterweed coverage were closely related to NH3-N, H3PO4 and DO. From July to October, the differences in morphology and weight of E. sinensis in different ponds became more and more significant. In terms of growth rate, C1S1 with a small area and low coverage had a downward trend, while C2S1 and C2S2 were the opposite. In the final stage of the experiment, C2S2 had the highest yield (0.1311 kg/m2), and C1S1 had the lowest yield (0.0600 kg/m2). Then, the ponds with high waterweed coverage and large area can bring better benefits. [ABSTRACT FROM AUTHOR]

Heavy metal pollution has become increasingly prominent, and bioremediation of heavy metal polluted areas is urgently needed. Broussonetia papyrifera is a pioneer tree species for vegetation restoration in the tailings area, while its molecular mechanism of heavy metal adaptation is not clear. Here, we report that a R2R3 MYB from B. papyrifera (BpMYB1) is involved in Cd accumulation by controlling the down-stream genes and mineral accumulation. Overexpression of BpMYB1 in B. papyrifera resulted in a significant increase in Cd accumulation and multiple gene transcription. Among the up-regulated genes, BpMYB1 could bind to ferrochelatase (BpFC2), basic helix-loop-helix transcription factor bHLH93 (BpbHLH93), and basic leucine zipper transcription factor bZIPs (BpbZIP1 , BpbZIP-CPC1) by recognizing TATCCAOSAMY (TATCCA) motif and related promoter segments. Further investigations revealed that overexpression of BpbZIP1 promotes the absorption of Cd, BpMYB1 regulate Cd uptake in plant relating to Fe accumulation without Fe-deficiency pathway via recognizing the downstream BpbHLH93 and involving in PCs biosynthetic pathway via recognizing the target BpFC2. Moreover, the Cd response effect mediated by BpMYB1 was boosted by interacting with a DELLA protein BpGAI1, a vital member of GA signaling. These results provide new insights into the molecular feedback mechanisms underlying BpMYB1-BpGAI1 controlled Cd uptake in plants, which will benefit for phytoremediation of Cd polluted soil. [Display omitted] • BpMYB1 overexpression benefits for Cd enrichment and tolerance of B. papyrifera. • BpMYB1 could regulate the transcription of multiple genes in Cd stress response. • The Cd stress response of BpMYB1 involves in the gibberellin-dependant signaling. • BpMYB1 could recognize downstream genes of BpFC2 , BpbHLH93 , BpbZIP1 , BpbZIP-CPC1. • BpFC2 , BpbHLH93 , BpbZIP1 , BpbZIP-CPC1 overexpression improves plant Cd uptake. [ABSTRACT FROM AUTHOR]

Woody plants are important source of edible oil, and Camellia hainanica and Camellia sinensis are two new option. The physicochemical properties and fatty acid composition were determined in both species. The oil content of C. hainanica was 37.60–41.60%, and that of C. sinensis was 31.04–33.20%. There were no significant differences in saponification value, refractive index or relative density (P > 0.05). The types of fatty acids were the same in both species, but the composition was significantly different (P < 0.01). Among the nine fatty acids measured, only the concentration of oleic acid was higher in C. hainanica oil than that C. sinensis oil. The contents of vitamin E and total phenols in C. hainanica oil were significantly higher than those in C. sinensis oil (P < 0.01). The higher unsaturated fatty acids, vitamin E, and total phenols, in C. hainanica give it a greater advantage. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A simple electrochemical method for detecting glutathione reductase was developed in this work. It was observed that the impedance of electrode increased obviously after the electrode modification by glutathione, and the value of impedance was closely related to the reduced glutathione (GSH) concentration. Based on the fact that glutathione reductase (GR) could catalyze oxidized glutathione (GSSG) to GSH rapidly in the presence of NADPH (β-nicotinamide adenine dinucleotide 2'-phosphate reduced), and as GSH was immobilized on the gold electrode surface, the impedance increased drastically. Meanwhile, it was found that the impedance was correlated with the activity of GR, and a chemical equation was obtained based on the relationship between the impedance and enzymatic activity. The range of enzymatic activity that could be measured at 0.005‒0.5 U by using this assay, and the detection limit was 0.005 U (1 U means reduction of 1.0 μmol GSSG per min at pH 7.2 at 25°C). The enzymatic activity of GR obtained by this method was compared with those obtained by colorimetric detection, and the results showed that the new method is reliable. Therefore, the new method is highly sensitive with convenience consuming time within 20 min to complete a test, thus showing a promising potential of being applied in medicine. [ABSTRACT FROM AUTHOR]

In this study, exogenous spermidine role on Salix matsudana tolerance to cadmium was evaluated. Spermidine and cadmium presented antagonistic effects on the biomass, copper and zinc concentrations in S. matsudana. cadmium mainly distributed in the cell wall of subcellular fraction; 46.97%–60.43% of cadmium existed in a sodium chloride-extracted form. Cadmium contents in roots, leaves, and twigs ranged from 2002.67 to 3961.00, 111.59 to 229.72, and 102.56 to 221.27 mg/kg, respectively. Spermidine application elevated cadmium concentrations in the roots, cuttings, and cell wall and the ratio of deionized water-extracted cadmium, but decreased cadmium levels in the twigs and leaves and the fractions of cadmium extracted by ethanol and sodium chloride, respectively. Putrescine and malondialdehyde were important indicators of cadmium-induced oxidative damage. Exogenous spermidine alleviated the accumulation of superoxide anion, hydrogen peroxide, malondialdehyde via promoting the levels of spermidine, soluble protein, superoxide dismutase, reductive ascorbate, glutathione reductase, and glutathione peroxidase in S. matsudana leaves under the corresponding cadmium stress. The results indicated that S. matsudana was a candidate for cadmium rhizoremediation and extraction in leaves; the spermidine application enhanced the cadmium tolerance of S. matsudana through promoting cadmium accumulation in roots, cell wall, and less bioactive chemical forms and the antioxidative ability. [ABSTRACT FROM AUTHOR]

Abstract A novel ternary composite of graphitic carbon nitride (g-C 3 N 4)/graphene oxide (GO) sheets/BiFeO 3 (CNGB) with highly enhanced visible-light photocatalytic activity toward Cr(VI) photoreduction is prepared and characterized. The characterization and photocatalysis experiments corroborate its reasonable band gap, efficient charge separation and transfer, widened visible-light adsorption, easy solid-liquid separation, good stability and superior catalytic activity of CNGB. Three CNGB samples with different ratios of g-C 3 N 4 and BiFeO 3 (CNGB-1, -2, -3 with 2:4, 3:3, and 4:2, respectively), though possessing different adsorption ability, eventually remove all Cr(VI) ions via photocatalysis within 90 min. The catalytic efficiency of the composite is the highest at pH 2; increases in pH decrease the catalytic ability. The inorganic anions such as SO 4 −, Cl−, and NO 3 − only slightly affects the photocatalytic process. The matching of the band structure between BiFeO 3 and g-C 3 N 4 generates efficient photogenerated electron migration from the conduction band of g-C 3 N 4 to that of BiFeO 3 , which is also facilitated by the electron bridging and collecting effects of GO, and holes transfer from the valence band of BiFeO 3 to that of g-C 3 N 4 , yielding the efficient separation of photogenerated electron-hole pairs and the subsequent enhancement of photocatalytic activity. The research provides a theoretical basis and technical support for the development of photocatalytic technologies for effective application in wastewater treatment and Cr-contaminated water restoration. Highlights • g-C 3 N 4 /graphene oxide/BiFeO 3 (CNGB) ternary assembly is easily prepared. • CNGB shows excellent photocatalysis of Cr (Ⅵ) reduction and easy removal from water. • CNGB shows maximized efficiency at low pH. • CNGB have little chance of electron-hole recombination. • CNGB shows great visible-light response. [ABSTRACT FROM AUTHOR]

Our study navigated investigated the metal adsorption ability of bacterial Bacillus cereus strain HM-5 isolated from manganese ore. The effects of pH, initial metal ions concentration, biomass dose, contact time, and temperature on biosorption were studied. The results showed that the biosorption capacity of the B. cereus strain HM-5 for the metallic ions reached up to 98.9% for Mn at 600 mg/L initial metal ion concentration. The biosorptoin was most affected by pH and incubation temperature. Optimal pH and temperature were 6 and 35°C, respectively. Optimal contact time was 5 d for biosorption by B. cereus strain HM-5. The surface chemical functional groups of B. cereus biomass identified by Fourier transform infrared (FTIR) were hydroxyl, alkyl, amide, phosphoryl, and phosphoric acid groups, which may be involved in the biosorption of heavy metals. SEM micrographs indicated that B. cereus HM-5 cells were irregular and cracked with the appearance of wrinkles and many flocs on the surface after Mn stress. The results showed that the selected bacteria had good application prospect in manganese-contaminated soil remediation. [ABSTRACT FROM AUTHOR]

Abstract A novel aptamer sensor for ratiometric ochratoxin A (OTA) detection was constructed based on the host-guest competition mode. Firstly, the aptamer modified with methylene blue (MB) at its terminal was fixed on the surface of the gold electrode via the host-guest recognition with β-cyclodextrin (β-CD). Then the MoS 2 nanosheets/Au NPs nanocomposites were used for the signal amplification. When OTA was present, the configuration of MB-aptamer transformed from vertical linear to G-quadruplex, thus making itself unable to get close to the electrode surface and causing a decrease in the redox current of the MB-aptamer. Whereas the free ferrocenecarboxylic acid could recognize and occupy the vacant site and produce signals in the current, resulting in the “ratiometric” effect. Consequently, on the basis of the “dual-signal” principle, a highly sensitive detection of OTA was made, indicating that the OTA concentration had a linear response to the signal of sensor between 0.1 nM and 50 nM, and as low as 0.06 nM OTA had been detected. Overall, this method for OTA detection was constructed easily with high sensitivity and specificity, providing a significant platform for highly efficient detection of OTA in biological samples. Graphical abstract Image 1 Highlights • A novel electrochemical sensor for ochratoxin A detection was developed. • MoS 2 nanosheets-Au NPs nanocomposites were used for the signal amplification. • OTA aptamer ensures the specificity of detection. • The merit of β-CD with superior recognition capability was employed. • The ratiometric strategy could avoid the majority of the interferences and maintain higher precision. [ABSTRACT FROM AUTHOR]

Background: Vacuolar H+-ATPase (V-ATPase) is a vital protein complex involved in abiotic stress response in plants. The G subunit of Juglans regia (JrVHAG1) was previously identified as a drought tolerance-related gene involved in the ABA (abscisic acid)-signal pathway. Heavy metal stress is becoming a major detriment for plant growth, development, and production. In order to understand the role of JrVHAG1, the potential function mechanism of JrVHAG1 exposed to CdCl2 stress was confirmed in this study. Results: Transcription of JrVHAG1 was induced by ABA and increased to 58.89-fold (roots) and 7.38-fold (leaves) and by CdCl2 to 2.65- (roots) and 11.42-fold (leaves) relative to control, respectively. Moreover, when treated simultaneously with ABA and CdCl2 (ABA+CdCl2), JrVHAG1 was up-regulated to 110.13- as well as 165.42-fold relative to control in the roots and leaves, accordingly. Compared to the wild type (WT) Arabidopsis plants, the transgenic plants with overexpression of JrVHAG1 (G2, G6, and G9) exhibited increased seed germination rate, biomass accumulation, proline content, and activities of superoxide dismutase (SOD) and peroxidase (POD) under ABA, CdCl2, and ABA+CdCl2 treatments. In contrast, the reactive oxygen species (ROS) staining, malondialdehyde (MDA) content, hydrogen dioxide (H2O2) content, as well as electrolyte leakage (EL) rates of transgenic seedlings were all lower than those of WT exposed to ABA, CdCl2 and ABA+CdCl2 stresses. Furthermore, a 1200 bp promoter fragment of JrVHAG1 was isolated by analyzing the genome of J. regia, in which the cis-elements were identified. This JrVHAG1 promoter fragment showed expression activity that was enhanced significantly when subjected to the above treatments. Yeast one-hybrid assay and transient expression analysis demonstrated that JrMYB2 specifically bound to the MYBCORE motif and shared similar expression patterns with JrVHAG1 under ABA, CdCl2 and ABA+CdCl2 stress conditions. Conclusions: Our results suggested that the JrVHAG1 gene functions as a CdCl2 stress response regulator by participating in ABA-signal pathway and MYB transcription regulation network. JrVHAG1 gene is a useful candidate gene for heavy metal stress tolerance in plant molecular breeding. [ABSTRACT FROM AUTHOR]

A method for grafting ethylenediamine to a magnetic graphene oxide composite (EDA-GO@Fe3O4) was developed for Cr(VI) decontamination. The physicochemical properties of EDA-GO@Fe3O4 were characterized using HRTEM, EDS, FT-IR, TG-DSC, and XPS. The effects of pH, sorbent dose, foreign anions, time, Cr(VI) concentration, and temperature on decontamination process were studied. The solution pH can largely affect the decontamination process. The pseudo-second-order model is suitable for being applied to fit the adsorption processes of Cr(VI) with GO@Fe3O4 and EDA-GO@Fe3O4. The intra-particle diffusion is not the rate-controlling step. Isotherm experimental data can be described using the Freundlich model. The effects of multiple factors on the Cr(VI) decontamination was investigated by a 25−1 fractional factorial design (FFD). The adsorption process can significantly be affected by the main effects of A (pH), B (Cr(VI) concentration), and E (Adsorbent dose). The combined factors of AB (pH × Cr(VI) concentration), AE (pH × Adsorbent dose), and BC (Cr(VI) concentration × Temperature) had larger effects than other factors on Cr(VI) removal. These results indicated that EDA-GO@Fe3O4 is a potential and suitable candidate for treatment of heavy metal wastewater. [ABSTRACT FROM AUTHOR]

The protective role of spermidine addition in media to Salix matsudana exposed to Pb was investigated by a hydroponic experiment in this study. The application of spermidine enhanced the biomass of S. matsudana exposed to Pb. Pb induced an increase in Pb levels in all organs of S. matsudana with the order of roots (maximum of 27616.0 mg/kg DW) > cuttings > twigs > leaves. Exogenous spermidine promoted the accumulation of Pb in the roots, but inhibited the Pb translocation to the shoots and thus the Pb content in the twigs and leaves. The Pb-induced decrease in the concentrations of spermidine, soluble protein, and nitric oxide was elevated by the application of spermidine in the leaves of S. matsudana . Exogenous spermidine could also effectively up-regulate the antioxidative capacity and reduced the accumulation of superoxide anion, hydrogen peroxide, malondialdehyde, and putrescine. The results suggested that S. matsudana could accumulate a high level of Pb in the roots, and exogenous spermidine could enhance S. matsudana tolerance to Pb by the synergistic promotion of Pb accumulation in the roots and the levels of spermidine, nitric oxide, and antioxidants in the leaves. [ABSTRACT FROM AUTHOR]

Modifying energy band structure and increasing absorption are two efficient strategies to improve the photocatalytic performance of semiconductor photocatalysts. In this study, a novel biochar (BC) based photocatalyst, nitrogen-doped (N-doped) BC based PbMoO 4 (NPBC) was developed by combining both strategies. After loading PbMoO 4 on poplar sawdust via in situ method, the composites were pyrolyzed in the presence of a certain amount of urea. Nitrogen doping successfully increased the specific surface area and narrowed the bandgap of the composite of PbMoO 4 @BC (PBC) to improve its adsorption-photocatalytic performance. NPBC-2, in which the ratio of PbMoO 4 : poplar sawdust was 3:1.6, exhibited excellent adsorption-photocatalytic removal for 40 mg L−1 tetracycline (TC) under visible light and the total removal rate was 88.25%, which was 1.60 and 3.46 folds of that for PBC and PbMoO 4, respectively. The adsorption kinetic of TC removal by NPBC-2 fitted well with pseudo fist order models, and the adsorption was dominated by the physical process. Vacancies (h+) and superoxide radicals (•O 2 −) were the main active species for TC photodegradation. In addition, after 5 cycles, the composite still exhibited high ability for TC removal. Therefore, N-doped BC based photocatalysts provided a feasible and effective way for the remediation of organism-contaminated water. • A novel PbMoO 4 @NBC catalyst was synthetic by combing precipitation and calcination. • The N doping shorten the band gap of the PBC. • The N-doped on PBC enhanced separation efficiency of electron-hole pairs. • The N-doped on PBC improved the adsorption capacity and removal efficiency of TC. [ABSTRACT FROM AUTHOR]

Developing broad-spectrum light reactions, effective charge separation, and easily recoverable photocatalysts were considered cost-effective pollution remediation methods. The ZnFe 2 O 4 /BC/ZnO composite was prepared to achieve these objectives, where biochar (BC) was used as a conductive channel and ZnFe 2 O 4 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 ZnFe 2 O 4 /BC, ZnO, and ZnFe 2 O 4 /ZnO samples, respectively. According to several characterization data, it was demonstrated that successful Z-scheme heterojunctions were constructed between ZnFe 2 O 4 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. [Display omitted] • A novel ZnFe 2 O 4 /BC/ZnO (ZBO) Z-scheme heterojunction was successfully constructed. • The ZBO heterojunction promotes the separation of electron-hole pairs. • BC as a conductive channel of ZnO and ZnFe 2 O 4. • The ZBO composite was relatively effective to remove TC from the wastewater. [ABSTRACT FROM AUTHOR]

Developing efficient and economical photocatalysts was considered as an efficient and economical strategy for pollution remediation. Herein, magnetically separable ZnFe 2 O 4 /CuWO 4 composites (ZW) had been developed via combining ZnFe 2 O 4 with CuWO 4. The composite with a mass ratio of 40% CuWO 4 (ZW-40) performed best, and the tetracycline hydrochloride (TC) removal by adsorption-photocatalysis of ZW-40 reached 86.5%. The photocatalytic degradation rated constant of it was 9.44 × 10−3 min−1, which was approximately 5.04 and 3.28 times compared to the ZnFe 2 O 4 and CuWO 4 samples, respectively. Pseudo-second-order kinetic models could describe well the TC adsorption process, in which chemisorption was the major driving factor, with the maximum adsorption at 23.56 mg g−1. The improved photo-catalytic capability owed to the formation of Z-scheme heterojunctions with ZnFe 2 O 4 and CuWO 4 , which improved the intensity of visible light absorption and enhanced the separation electron-hole pairs as well as the redox capability of the composite. ZW-40 was high stability as its removal ability of TC in different water conditions slightly dropped about 15% after 5 cycles. ZW-40 could effectively remove TC in different water matrix, its removal ability for 40 mg/L was as follows: super-pure water> municipal wastewater> swine farm wastewater. Hence, the complexation of ZnFe 2 O 4 with CuWO 4 provides a valuable strategy to improve the photocatalytic potential for ZnFe 2 O 4 -based catalysts as well as providing a promising pathway for water clarification. • A novel ZnFe 2 O 4 /CuWO 4 (ZW) Z-scheme heterojunction was successfully constructed. • Heterojunction between ZnFe 2 O 4 and CuWO 4 promotes the electron-hole pair separation. • Synergistic adsorption-photocatalysis could more effectively remove tetracycline. • The ZW composite was relatively effective to remove TC from the wastewater. [ABSTRACT FROM AUTHOR]

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 PbMoO 4 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 PbMoO 4 to BC = 1:4; 1:1; and 4:1, respectively) displayed higher activity than pure PbMoO 4. The results showed that the composite with the PbMoO 4 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 PbMoO 4 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 (O 2 −) 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 PbMoO 4 provides a useful strategy for improving the photocatalytic ability of PbMoO 4 -based photocatalysts and offers a promising method for water purification. [Display omitted] • Using poplar sawdust as biochar source realized the rational application of waste. • In situ synthesis enhanced the adsorption and photocatalytic activity of PbMoO 4. • Superior electrical conductivity of BC helps transport of photogenerated carrier. • BC strengthened the visible light response of PbMoO 4 @BC-1. • PbMoO 4 @BC-1 showed promising visible-light photodegradation for TC degradation. [ABSTRACT FROM AUTHOR]