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It is generally accepted that sulfur can passivate the bioavailability of heavy metals in soil, but it is not clear whether high sulfur in cadmium (Cd) and chromium (Cr) contaminated soil has negative effect on soil microbial community and ecological function. In this study, total sulfur (TS) inhibited the Chao 1, Shannon, Phylogenetic diversity (Pd) of bacterial and Pd of fungi in slightly contaminated soil by Cd and Cr around pyrite. TS, total potassium, pH, total chromium, total cadmium, total nitrogen, soil organic matter were the predominant factors for soil microbial community; the contribution of TS in shaping bacterial and fungal communities ranked at first and fifth, respectively. Compared with the low sulfur group, the abundance of sulfur sensitive microorganisms Gemmatimonas , Pseudolabrys , MND1 , and Schizothecium were decreased by 68.79–97.22% (p < 0.01) at high sulfur one; the carbon fixation, nitrogen cycling, phosphorus cycling and resistance genes abundance were significantly lower (p < 0.01) at the latter. Such variations were strongly and closely correlated to the suppression of energy metabolism (M00009, M00011, M00086) and carbon fixation (M00173, M00376) functional module genes abundance in the high sulfur group. Collectively, high sulfur significantly suppressed the abundances of functional microorganisms and functional genes in slightly contaminated soil with Cd and Cr, possibly through inhibition of energy metabolism and carbon fixation of functional microorganisms. This study provided new insights into the environmental behavior of sulfur in slightly contaminated soil with Cd and Cr. [Display omitted] • Sulfur was a key factor affecting soil microbial community near mines. • High sulfur inhibited abundance of soil functional microbes. • The functional & resistance genes were suppressed by high sulfur. • Functional microbes were inhibited via energy metabolism and carbon fixation. [ABSTRACT FROM AUTHOR]

Urbanization has progressively intensified over the past few decades, transforming the structure and function of urban ecosystems and influencing the concentrations and spatial distributions of phosphorus (P) in the soil. This study collected 177 surface soil samples (to a depth of 20 cm) to understand the dynamics of soil P along a gradient of urbanization from a densely urbanized central city to less human-affected suburbs to a new exurban satellite in Chengdu, China. The results showed that concentrations of soil total P (TP) and its fractions (except Water-Po, NaOH-Pi, and Residual-P) in the central city and exurban satellite were significantly higher than in suburban areas ( p  < 0.05). Meanwhile, the concentrations of soil TP and its fractions (except Residual-P) significantly decreased with the increase in distance from the urban center ( p  < 0.05). These concentrations were significantly positively correlated with the densities of built-up areas and roads, and showed significant differences among different green space types. The results of generalized linear models indicated that the most decisive factors contributing to TP accumulation were the distance from urban center and green space type. Generally, green space type and density of built-up area were likely to be more crucial determinants governing soil inorganic P fractions compared with other factors, whereas the key factors affecting soil organic P fractions were varied. To conclude, urbanization is likely to lead to the accumulation of P and, thus, controlling the expansion of built-up areas and road areas is necessary to alleviate soil P accumulation in urban systems. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the effects of short-term root-zone hypoxic stress and exogenous calcium application or deficiency in an anoxic nutrient solution on nitrogen metabolism in the roots of the muskmelon cultivar Xiyu No. 1. Seedlings grown in the nutrient solution under hypoxic stress for 6d displayed significantly reduced plant growth and soluble protein concentrations. However, NO3 − uptake rate and activities of nitrate reductase and glutamate synthase were significantly increased. We also found higher amounts of nitrate, ammonium, amino acids, heat-stable proteins, polyamines, H2O2, as well as higher polyamine oxidase activity in the roots. In comparison to the reactions seen under hypoxic stress, exogenous calcium application led to a marked increase in plant weights, photosynthesis parameters, NO3 − uptake rate and contents of nitrate, ammonium, amino acids (e.g., glutamic acid, proline, glycine, cystine, γ-aminobutyric acid), soluble and heat-stable proteins, free spermine, and insoluble bound polyamines. Meanwhile, exogenous calcium application resulted in significantly increased activities for nitrate reductase, glutamine synthetase, and glutamate synthase but decreased activities for diamine and polyamine oxidase, as well as lower H2O2 content in roots during exposure to hypoxia. However, calcium deficiency in the nutrient solution decreased plant weight, photosynthesis parameters, NO3 − reduction, amino acids (e.g., alanine, aspartic acid, glutamic acid, γ-aminobutyric acid), protein, all polyamines except for free putrescine, and the activities of glutamate synthase and glutamine synthetase. Additionally, there was an increase in the NO3 − uptake rate, polyamine oxidase activity and H2O2 contents under hypoxia–Ca. Simultaneously, exogenous calcium had little effect on nitrate absorption and transformation, photosynthetic parameters, and plant growth under normoxic conditions. These results suggest that calcium confers short-term hypoxia tolerance in muskmelon, most likely by promoting nitrate uptake and accelerating its transformation into amino acids, heat-stable proteins or polyamines, as well as by decreasing polyamine degradation in muskmelon seedlings. [Copyright &y& Elsevier]

Chemical washing is considered an effective technique for removing heavy metals (HMs) from industrial sludge. However, traditional washing methods have the potential to cause secondary environmental pollution. In this study, a new chemical washing strategy that circumvents the risk of secondary contamination by using two organic acid polymers—Caboxyethylthiosuccinic acid (CETSA) and itaconic-acrylic acid copolymer (IA-AA) were introduced to remove Pb, Zn, Ni and Cr from industrial sludge. The quantity of HMs removed from the sludge increases as a function of increasing agent concentration, Solid-to-liquid ratio, and washing time, while various trends were observed in response to increasing pH. In addition, response surface analysis showed that CETSA concentration significantly affected HM removal; and IA-AA concentration, pH, and washing time showed evident impacts on washing efficiency. Optimal washing specifications using CETSA, with respect to agent concentration, pH, and washing time, were 66.76 g/L, 2.76, and 248 min, respectively; while those of IA-AA were 100 g/L, 2, and 360 min, respectively. CETSA and IA-AA removed 69.04% and 98.31% of total HMs, respectively, and decreased the labile fractions of Zn and Ni. Fourier transform infrared spectroscopy analysis suggested that the hydroxyl, carboxyl, carbonyl might contribute to the heavy metal extraction. Overall, CETSA and IA-AA should be seriously considered as reliable washing agents for use in HM removal from sludge. [Display omitted] • CETSA and IA-AA can effectively remove Pb, Zn, Ni and Cr from industrial sludge. • Optimal washing specifications were obtained using Response surface methodology. • CTESA and IA-AA washing decreased the labile fraction concentration of heavy metals. [ABSTRACT FROM AUTHOR]

The purpose of this study was to synthesize FeS/chitosan/biochar composite (FSBC) to remove Cr(VI). Results indicate that the modification of FeS particles and chitosan to biochar provided large specific surface area and more active adsorption sites. FSBC(1:1:1) have an enhanced Cr(VI) adsorption capacity of 103.93 mg g-1 at 0.01 g per 50 mL Cr(VI) solution compared with 19.97 mg g−1 for FeS particles and 22.45 mg g−1 for biochar. Increasing temperature promote Cr(VI) removal. By contrast, increasing Cl- and SO42- concentrates and solution pH prevented Cr(VI) adsorption. Cr(VI) removal could attribute to surface adsorption, reduction and precipitation. XPS results indicated that 76.07% of Cr(VI) removal was due to reduction or precipitation, and 23.93% could be ascribed to surface adsorption. After adsorption-desorption cycle, Cr(VI) removal capacities are 70.42, 65.33 and 11.67 mg g−1 for FSBC(1:1:1), FSBC(1:1:5) and FSBC(5:5:1), respectively. The study demonstrated that FSBC were high-effective adsorbents for Cr(VI) removal in the water environment. [Display omitted] • FSBC was synthesized combining the advantages of biochar, chiostan, and FeS. • FSBC(1:1:1) has an enhanced Cr(VI) removal capacity of 103.93 mg g−1. • Cr(VI) removal could attribute to surface adsorption, reduction and precipitation. [ABSTRACT FROM AUTHOR]

• Metabolic dynamics of L. ruthenicum fruit was monitored using UHPLC-MS/MS. • A total of 49 compounds were tentatively identified in the fruits. • Four developmental stages can be easily distinguished by PCA. • Positive correlation between anthocyanin and spermidine derivative hexoses was found. • The positive correlation was attributed to a glycosyltransferase HG27071. The Lycium ruthenicum (Lr) fruit is a widely used nutritional food that contains various bioactive components such as anthocyanin and spermidine derivatives. In the present study, ultra-high-performance liquid chromatography with tandem mass spectrometry was utilized to profile the metabolic dynamics of four developmental stages of Lr fruit. A total of 49 compounds, including anthocyanin, alkaloids, hydroxycinnamic acid derivatives, flavonoids, and amino acids, were tentatively identified. Principal component analysis distinguished the fruit at four developmental stages using 15 (9 were tentatively identified) potential marker compounds. Pearson correlation analysis suggested that anthocyanin and spermidine derivative hexoses had a strong positive correlation coefficient. A glucosyltransferase (HG27071) was confirmed to glucosylate both anthocyanidin and spermidine derivative in vitro. Our results provide insight into the metabolic linkages among bioactive components in Lr fruits. The glucosyltransferase identified in this study will promote its potential use in functional foods and natural pigment resources. [ABSTRACT FROM AUTHOR]

The second recovery of rare earth elements from the bastnaesite-rich slags can effectively alleviate their industry demand and achieve cleaner production, but it still remains unclear and difficult to remove impurities from the leachate by hydrochloric acid. In this study, NaOH and NH 4 HCO 3 as precipitants were used to remove impurities and explore the optimal precipitation conditions and the mechanism by the D-optimal mixture design. The results showed that among the factors of temperature, pH and concentration, pH was the key affecting factor in impurity removal by the two reagents. The synergistic effect between the temperature and concentration promoted the impurity removal for NaOH and NH 4 HCO 3 , and the antagonism of pH with temperature inhabited the removal in the NH 4 HCO 3 group. At the optimal conditions of 35.7–70.0 °C, 2.0–6.0 solution pH and 2.0–6.0 mol L−1 concentrations, the removal rates of Fe3+, Al3+, and Cu2+ by the NaOH were about 100, 64.9, and 58.4%, respectively, and those were about 100, 36.1, and 26.6% under the optimal conditions of 25.9–60.0 °C, 3.0–5.0 solution pH and 0.5–2.5 mol L−1 concentrations by NH 4 HCO 3 , respectively. Therefore, NaOH and NH 4 HCO 3 are two feasible reagents for impurity removal in rare earth leachate for cleaner production. [Display omitted] • Impurity ions were effectively removed by NaOH and NH 4 HCO 3. • D-optimal mixture design was first employed for impurity removal optimization. • Interaction between temperature and concentration lifted the impurity removal. • The REEs recovery efficiencies are 99.6 and 94.4% in optimized conditions. [ABSTRACT FROM AUTHOR]

Soil washing with chelators is a promising and efficient method of remediating metals-contaminated soils. However, the toxicity of residual metals and the effects on soil microbial properties have remained largely unknown after washing. In this study, we employed four biodegradable chelators for removal of metals from contaminated soils: iminodisuccinic acid (ISA), glutamate-N,N-diacetic acid (GLDA), glucomonocarbonic acid (GCA), and polyaspartic acid (PASP). The maximum removal efficiencies for Cd, Pb, and Zn of 85, 55, and 64% and 45, 53, and 32% were achieved from farmland soil and mine soil using biodegradable chelators, respectively. It was found that the capacity of ISA and GLDA to reduce the labile fraction of Cd, Pb, and Zn was similar to that of the conventional non-biodegradable chelator ethylenediaminetetraacetic acid (EDTA). The leachability, mobility, and bioaccessibility of residual metals after washing decreased notably in comparison to the original soils, thus mitigating the estimated environmental and human health risks. Soil β-glucosidase activity, urease activity, acid phosphatase activity, microbial biomass nitrogen, and microbial biomass phosphorus decreased in the treated soils. However, compared with EDTA treatment, soil enzyme activities distinctly increased by 5–94% and overall microbial biomass slightly improved in the remediated soils, which would facilitate reuse of the washed soils. Based on soil toxicity tests that employed wheat seed germination as the endpoint of assessment, the washed soils exhibited only slight effects especially after ISA and GLDA treatments, following high-efficiency metal removal. Hence, ISA and GLDA appear to possess the greatest potential to rehabilitate polluted soils with limited toxicity remaining. [ABSTRACT FROM AUTHOR]

Banana is a tropical fruit widely accepted by people over the world. Its chemical composition is critical for its organoleptic properties and nutritional value. In this work, the metabolite changes during postharvest senescence were investigated using NMR spectroscopy. The 1D and 2D NMR spectroscopic information revealed the primary and secondary metabolites in banana fruit, including organic acids, amino acids, carbohydrates and phenolics. Bananas at five senescence stages showed similar chemical profiles, but the levels of the individual compounds varied to a large extent. The principal metabolites responsible for postharvest senescence of banana were valine, alanine, aspartic acid, choline, acetate, glucose, malic acid, gallic acid and dopamine. At stage V, ethanol was present due to the conversion of glucose. Salsolinol was generated due to the conversion of dopamine. This was a characteristic marker for the postharvest senescence of banana fruit. [ABSTRACT FROM AUTHOR]

Soil washing, an emerging method for treating soils contaminated by heavy metals, requires an evaluation of its efficiency in simultaneously removing different metals, the quality of the soil following remediation, and the reusability of the recycled washing agent. In this study, we employed N , N -bis (carboxymethyl)- l -glutamic acid (GLDA), a novel and readily biodegradable chelator to remove Cd, Pb, and Zn from polluted soils. We investigated the influence of washing conditions, including GLDA concentration, pH, and contact time on their removal efficiencies. The single factor experiments showed that Cd, Pb, and Zn removal efficiencies reached 70.62, 74.45, and 34.43% in mine soil at a GLDA concentration of 75 mM, a pH of 4.0, and a contact time of 60 min, and in polluted farmland soil, removal efficiencies were 69.12, 78.30, and 39.50%, respectively. We then employed response surface methodology to optimize the washing parameters. The optimization process showed that the removal efficiencies were 69.50, 88.09, and 40.45% in mine soil and 71.34, 81.02, and 50.95% in polluted farmland soil for Cd, Pb, and Zn, respectively. Moreover, the overall highly effective removal of Cd and Pb was connected mainly to their highly effective removal from the water-soluble, exchangeable, and carbonate fractions. GLDA-washing eliminated the same amount of metals as EDTA-washing, while simultaneously retaining most of the soil nutrients. Removal efficiencies of recycled GLDA were no > 5% lower than those of the fresh GLDA. Therefore, GLDA could potentially be used for the rehabilitation of soil contaminated by heavy metals. [ABSTRACT FROM AUTHOR]

The cost–effective removal and recovery of phosphate from wastewater is of great importance to controlling eutrophication and alleviating the phosphorus resource exhaustion crisis. Herein, chitosan (Cs) encapsulated bimetallic lanthanum (La) and iron (Fe) metal(hydro) oxides (La/Fe–Cs) composites were fabricated using a co–precipitated method for enhanced phosphate removal and recovery. The La/Fe–Cs composites had rough and raised spongy–like surfaces coated with La/Fe (hydr)oxide particles with a high specific surface area of 109.84 m2 g−1, providing more potential binding sites for phosphate capture. The La/Fe–Cs composites with a 1:2 La–to–Fe molar ratio exhibited a maximum adsorption capacity of 67.52 mg g−1 for phosphate at 308 K, calculated using the Langmuir model, which was 211% higher than that of monometallic Fe–Cs composites. Meanwhile, this composite also showed a high phosphate removal rate (63–95%) in an extensive applicable pH range (3.00–10.00) and rapid adsorption within 10 min (up to 94%). Moreover, the adsorption of phosphate by La/Fe–Cs composites was mildly disturbed against co–existing ions of NO 3 −, Cl−, and humic acid, while adsorption capacities were reduced by almost 13–45% with the existence of SO 4 2−, HCO 3 −, and CO 3 2−. The FTIR, XPS, and DFT results suggested that La–doped facilitated phosphate removal and the predominant mechanisms involved electrostatic interaction, surface precipitation, and inner–sphere complexation processes. Additionally, La/Fe–Cs composites also illustrated excellent efficiencies in simultaneous scavenging phosphate and ammonia from eutrophication and poultry wastewater. These results highlight bimetallic La/Fe–Cs composites are promising candidates for efficient elimination and recovery of phosphate from real wastewater, and subsequently could be used as slow–release fertilizers or soil amendments. [Display omitted] •Bimetallic La/Fe–Cs composites were synthesized for phosphate removal. • The derived bimetallic La/Fe–Cs composites showed excellent phosphate adsorption capacity of 67.52 mg g−1 • Mechanisms driving phosphates adsorbed onto the La/Fe–Cs composites were elucidated by FTIR, XPS, and DFT. • High efficiency in scavenging phosphate from eutrophication wastewater and poultry wastewater. • The phosphate–loden La/Fe–Cs composites can be used as slow–release fertilizers or soil amendments. [ABSTRACT FROM AUTHOR]

Estimating the spatial distribution of soil nitrogen at different scales is crucial for improving soil nitrogen use efficiency and controlling nitrogen pollution. We evaluated the spatial variability of soil total nitrogen (TN) and available nitrogen (AN) in the Fujiang River Valley, a typical hilly region composed of low, medium and high hills in the central Sichuan Basin, China. We considered the two N forms at single hill, landscape and valley scales using a combined method of classical statistics, geostatistics and a geographic information system. The spatial patterns and grading areas of soil TN and AN were different among hill types and different scales. The percentages of higher grades of the two nitrogen forms decreased from low, medium to high hills. Hill type was a major factor determining the spatial variability of the two nitrogen forms across multiple scales in the valley. The main effects of general linear models indicated that the key affecting factors of soil TN and AN were hill type and fertilization at the single hill scale, hill type and soil type at the landscape scale, and hill type, slope position, parent material, soil type, land use and fertilization at the valley scale. Thus, the effects of these key factors on the two soil nitrogen forms became more significant with upscaling. [ABSTRACT FROM AUTHOR]

The water-soluble bioactive polysaccharides can contribute to the health benefits of Lycium barbarium fruit. However, the structure characteristics of these polysaccharides remain unclear yet. An important polysaccharide (LBPA) was isolated and purified from L. barbarium in this work. It was identified by chemical and spectroscopic methods as arabinogalactan with β- d -(1 → 6)-galactan as backbone, which was different to any reported polysaccharides from this species before. This arabinogalactan was comprised of Ara f , Gal p , Glc p A and Rha p with a molar ratio of 9.2:6.6:1.0:0.9. The side chains, including α- l -Ara f -(1→, α- l -Ara f -(1 → 5)-α- l -Ara f -(1→, β- l -Ara f -(1 → 5)-α- l -Ara f -(1→ and α- l -Rha p -(1 → 4)-β- d -Glc p A-(1 → 6)-β- d -Gal p -(1→, were linked to β- d -(1 → 6)-galactan at O-3. The putative structure was drawn as below. The molecular weight was determined to be 470,000 g/mol by gel permeation chromatography. [ABSTRACT FROM AUTHOR]

Fruit of two different papaya cultivars (‘Sui huang’, yellow flesh, and ‘Sui hong’, red flesh) were characterized in terms of carotenoid and volatile profiles throughout storage at 25 °C. The results showed that ‘Sui huang’ cultivar exhibited significantly lower carotenoid contents than ‘Sui hong’, which accounted for the different color characteristic. The analyses of HPLC coupled to mass spectrometry showed that zeaxanthin, β-cryptoxanthin and and β-carotene were identified as the most abundant carotenoids in ‘Sui huang’ fruit while the most abundant carotenoids were lycopene, followed by β-carotene, zeaxanthin and β-cryptoxant hin in ‘Sui hong’ fruit. The high expression of carotenoid cleavage dioxygenase gene ( CpCCD1 ) in ‘Sui hong’ papaya fruit might stimulate the degradation of β-carotene and lycopene and then form the specific volatiles of 6-methyl-5-hepten-2-one and β-ionone. [ABSTRACT FROM AUTHOR]

Guanglin 9 ( Eucalyptus grandis × Eucalyptus urophlla ) and Eucalyptus grandis 5 are two eucalyptus species which have been found to grow normally in soils contaminated with lanthanum and cerium, but the tolerance mechanisms are not clear yet. In this study, a pot experiment was conducted to investigate the tolerance mechanisms of the eucalyptus to lanthanum and cerium. Cell walls stored 45.40–63.44% of the metals under lanthanum or cerium stress. Peroxidase and catalase activities enhanced with increasing soil La or Ce concentrations up to 200 mg kg −1 , while there were no obvious changes in glutathione and ascorbate concentrations. Non-protein thiols concentrations increased with increasing treatment levels up to 200 mg kg −1 , and then decreased. Phytochelatins concentrations continued to increase under La or Ce stress. Therefore, the two eucalyptus species are La and Ce tolerant plants, and the tolerance mechanisms include cell wall deposition, antioxidant system response, and thiol compound synthesis. [ABSTRACT FROM AUTHOR]

• Marsh degradation reduced large-aggregate ratio and SOC content in aggregates. • Dominant aggregate size of SOC preservation decreased under marsh degradation. • SOC active functional groups in aggregates increased along degraded marsh gradient. • Marsh degradation weaken organic C stability and sequestration in soil aggregates. Alpine marsh wetlands in the Qinghai-Tibetan Plateau are ecological hotspots for global carbon (C) cycling in Central Asia; however, the soil C sinks are increasingly limited by marsh degradation. To assess the physical mechanisms by which changes in the soil C sequestration occur, the distribution and functional groups of soil organic C (SOC) in aggregates along a marsh degradation gradient on the Zoige Plateau in China were investigated using soil samples collected from differently degraded marshes. Our results showed that, beyond the state of light degradation, the large aggregate content decreased significantly by 31.1–55.2%, while the micro-aggregate content increased significantly by 23.1–93.1%. The SOC content in the aggregates decreased significantly by 39.1–84.8% and the dominant aggregate size for SOC preservation decreased to small or micro-aggregate. Marsh degradation also decreased the relative ratio of aliphatic-C while increasing that of alcohol and phenolic-C, and polysaccharide-C. Index I (relative decomposition of SOC in aggregates) was 73.5–429.0% higher for degraded marshes than for relatively pristine marsh (RPM), while Index Ⅱ (relative recalcitrance of SOC in aggregates) was 13.8–79.5% lower in comparison. Therefore, we concluded that marsh degradation probably reduces the organic C sequestration capacity of soil by increasing the decomposition of SOC in aggregates after both the dominant aggregate size for SOC preservation and aggregate stability decreased. This result represents the physical mechanism by which the decrease in SOC content occurs in response to marsh degradation in alpine regions. [ABSTRACT FROM AUTHOR]

Abstract: Chelant assisted phytoextraction has been proposed to enhance the efficiency of remediation. This study evaluated the effects of biodegradable ethylene diamine tetraacetate (EDDS), nitrilotriacetic (NTA) and anionic polyacrylamide (APAM) on the tolerance and uptake of Siegesbeckia orientalis L. at 10 and 100mgkg−1 Cd-contaminated soils. On the 80th and 90th days of transplanting, pots were treated with EDDS and NTA at 0 (control), 1 and 2mmolkg−1 soils, and APAM at 0 (control), 0.07 and 0.14gkg−1. Generally, the root and shoot biomass of S. orientalis in all treatments reduced not significantly compared with the control, and the activities of peroxidase and catalase in leaves generally increased by the application of chelants (P <0.05). The concentrations of Cd in the shoots were increased significantly by addition of all chelants. As a result, the Cd accumulation of S. orientalis under treatments with higher dosages of the three chelants on the 80th day were 1.40–2.10-fold and 1.12–1.25-fold compared to control at 10 and 100mgkg−1 Cd, respectively. Under the addition of 2mmolkg−1 NTA on the 80th day, the highest metal extraction ratio reached 1.2% and 0.4% at 10 and 100mgkg−1 Cd soils, respectively. Therefore, the applications of EDDS, NTA and APAM may provide more efficient choices in chemical-enhanced phytoextraction. [Copyright &y& Elsevier]

Abstract: Identification of new higher yield cadmium (Cd)-hyperaccumulating cultivars from native species is key to the phytoremediation of Cd contaminated soils. A pot experiment with different soil Cd concentrations and a plot experiment at 28.44mgCdkg−1 were conducted to investigate Cd tolerance and accumulation by Siegesbeckia orientalis following a field survey. In the pot experiment, at Cd concentration of 150mgkg−1, S. orientalis grew normally and shoot biomass was not reduced significantly compared with the no Cd control. The activities of superoxide dismutase and catalase in roots and leaves, and peroxidase in leaves significantly increased with increasing soil Cd (P <0.05). The highest shoot Cd concentrations were 117.48, 192.92 and 77.10mgkg−1, in the field survey, pot and plot experiments, respectively and their corresponding accumulations were 6.762mgplant−1, 4.134mgpot−1 and 18.45mgm−2. All Cd bioconcentration factors and translocation factors were more than 1.0. Therefore, S. orientalis is a Cd-accumulator with hyperaccumulating ability. [Copyright &y& Elsevier]

Abstract: Two alkali-soluble polysaccharide fractions (ASPs I and II) were extracted from longan fruit pericarp in this work. The results of chemical composition indicated that ASP I and II fractions comprised mainly of polysaccharides, proteins and lignins. Four monosaccharides, namely Xyl, Ara, Glc and Gal, were identified for both ASPs I and II. Xyl was the dominant monosaccharide in the two alkali-soluble polysaccharides with relative molar percentages of >60%. It constructed the backbone in combination with Ara for both ASPs I and II. The analysis of glycosidic linkage indicated that Xyl had two linkages,→3)-Xyl-(1→ and →3, 4)-Xyl-(1→. The substitution at C-4 position indicated that Xyl was of pyranose structure. The infrared spectra of ASPs I and II showed the characteristic bands at approximate 897cm−1 which indicated the β-linkage configuration of Xyl. Industrial relevance: Hemicellulose has been suggested as an important polysaccharide with good pharmaceutical properties, including immune modulation and anti-cardiovascular diseases. In this work, alkali-soluble polysaccharides were extracted from longan fruit pericarp and fractionated. The structural characteristics were identified by gas chromatography/mass spectrometry and infrared spectrophotometry. The results will be helpful for application of hemicellulose in functional food industry. [Copyright &y& Elsevier]

Excessive ammonium (NH 4 +) and phosphate (PO 4 3−) in aquatic environments can cause serious eutrophication. Agricultural waste is an efficient adsorbent for nutrients removal and has good potential for comprehensive utilisation of resources. In this study, two Chinese medicinal herbal residues, Rhizoma Typhonium Gigantei (ZB) and Radix Glycyrrhizae Preparata (ZG), were implemented to simultaneously remove NH 4 + and PO 4 3− from water. Parameters such as adsorbent dosage, solution pH, contact time and initial concentration that influenced the adsorption process onto adsorbents, along with removal mechanism and practical performance were investigated. The microstructure of ZB was irregular with numerous spherical particles, while ZG displayed an uneven flaky structure with few rough grooves. The nutrients adsorption was significantly influenced by pH. The maximum adsorption capacity by ZB was 91.84 N mg g−1 and 71.81 P mg g−1. In addition, the maximum adsorption capacity recorded by ZG was 100.86 N mg g−1 and 89.51 P mg g−1 (pH, 8.0; dosage, 0.2 g L−1; initial concentration, 60 mg L−1; and contact time, 180 min, for both the herbal residues). The adsorption of NH 4 + and PO 4 3− was well described by the pseudo-second-order and intra-particle diffusion models, respectively. The Langmuir isotherm model is the best fit model for the adsorption equilibrium data, suggesting monolayer adsorption of NH 4 + and PO 4 3− by the two adsorbents. In addition, NH 4 + was predominantly adsorbed by electrostatic attraction, ion exchange and complexation, whereas PO 4 3− was predominantly adsorbed by intra-particle diffusion and ligand exchange. Practical application analysis demonstrated that ZG could remove and recover more NH 4 + and PO 4 3− from swine wastewater than ZB. Therefore, ZG exhibited a more significant potential to simultaneously remove and recover NH 4 + and PO 4 3− from wastewater. [Display omitted] • Ammonium and phosphate can be effectively and simultaneously adsorbed. • Ammonium was removed by electrostatic attraction, ion exchange and complexation. • Phosphate was removed mainly by intra-particle diffusion and ligand exchange. • Chinese herbal medicine residues show great application potential in wastewater. • About 80% adsorbed ammonium and phosphate could be successfully recovered. [ABSTRACT FROM AUTHOR]