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Understanding the interactions of carbon and metal pollutants in anthropogenically impacted rivers is a prerequisite for determining the relative fates of these stressors. Here, through two sets of studies, we report carbon–metal pollutant interactions choosing the CO2 emission and sediment microbial extracellular enzyme activities as major determinants. The study, conducted along a 520-km main river and along a point source trajectory, showed a TOC-dependent but metal pollution-constrained CO2 emission. We found significant relationships (p < 0.05–0.001) between CO2 emission flux and its determinants: TOC, Cmic, FDAase and β-D-glucosidase. In the point source trajectory, CO2 emission flux was closely synchronous to these determinants. These relationships, however, were significantly constrained at the sites such as Knuj, Jjmu and Rjht where the concentrations of total heavy metal (∑THM) in the sediment exceed 347.44 µg g−1 indicating that the heavy metal pollution counteracted the C processing and consequently the CO2 emission flux. The study suggests that the excessive load of metal pollutants will eventually interrupt the C-cycling in the Ganga River inviting caution in C budgeting and C transport to coastal ocean. [ABSTRACT FROM AUTHOR]

The potential pollution risks and characteristics of heavy metal pollution in surface streams were assessed in a decommissioned uranium tailing. The results demonstrated that the concent of seven heavy metals in the tailing were comparatively high and were beyond the environmental quality standard limits of surface water. Correlation and enrichment factor studies demonstrated that mining operations were the main source of contamination. According to pollution evaluation indices, there was a high risk of contamination and notable enrichment and pollution features for Tl, Mo, Mn, U, and Al in the tailing. Ni and Cd were mildly contaminated and enriched. [ABSTRACT FROM AUTHOR]

Horizontal gene transfer plays a key role in the global dissemination of antimicrobial resistance (AMR). AMR genes are often carried on self-transmissible plasmids, which are shared amongst bacteria primarily by conjugation. Antibiotic use has been a well-established driver of the emergence and spread of AMR. However, the impact of commonly used non-antibiotic compounds and environmental pollutants on AMR spread has been largely overlooked. Recent studies found common prescription and over-the-counter drugs, artificial sweeteners, food preservatives, and environmental pollutants, can increase the conjugative transfer of AMR plasmids. The potential mechanisms by which these compounds promote plasmid transmission include increased membrane permeability, upregulation of plasmid transfer genes, formation of reactive oxygen species, and SOS response gene induction. Many questions remain around the impact of most non-antibiotic compounds on AMR plasmid conjugation in clinical isolates and the long-term impact on AMR dissemination. By elucidating the role of routinely used pharmaceuticals, food additives, and pollutants in the dissemination of AMR, action can be taken to mitigate their impact by closely monitoring use and disposal. This review will discuss recent progress on understanding the influence of non-antibiotic compounds on plasmid transmission, the mechanisms by which they promote transfer, and the level of risk they pose. [ABSTRACT FROM AUTHOR]

Modifying cells with polymers on the surface can enable them to gain or enhance function with various applications, wherein the atom transfer radical polymerization (ATRP) has garnered significant potential due to its biocompatibility. However, specifically initiating ATRP from the cell surface for in-situ modification remains challenging. This study established a bacterial surface-initiated ATRP method and further applied it for enhanced Cr(VI) removal. The cell surface specificity was facilely achieved by cell surface labelling with azide substrates, following alkynyl ATRP initiator specifically anchoring with azide–alkyne click chemistry. Then, the ATRP polymerization was initiated from the cell surface, and different polymers were successfully applied to in-situ modification. Further analysis revealed that the modification of Shewanella oneidensis with poly (4-vinyl pyridine) and sodium polymethacrylate improved the heavy metal tolerance and enhanced the Cr(VI) removal rate of 2.6 times from 0.088 h−1 to 0.314 h−1. This work provided a novel idea for bacterial surface modification and would extend the application of ATRP in bioremediation. [Display omitted] • ATRP specifically initiated from the bacterial cell surface was developed. • Bacterial cell was successfully modified by this new ATRP method. • The surface modified bacterial cell exhibited enhanced Cr(VI) removal. [ABSTRACT FROM AUTHOR]

Heavy metal Cd2+ can easily be accumulated by fungi, causing significant stress, with the fungal cell membrane being one of the primary targets. However, the understanding of the mechanisms behind this stress remains limited. This study investigated the changes in membrane lipid molecules of Pleurotus ostreatus mycelia under Cd2+ stress and the antagonistic effect of Ca2+ on this stress. Cd2+ in the growth media significantly inhibited mycelial growth, with increasing intensity at higher concentrations. The addition of Ca2+ mitigated this Cd2+-induced growth inhibition. Lipidomic analysis showed that Cd2+ reduced membrane lipid content and altered lipid composition, while Ca2+ counteracted these changes. The effects of both Cd2+ and Ca2+ on lipids are dose dependent and phosphatidylethanolamine appeared most affected. Cd2+ also caused a phosphatidylcholine/phosphatidylethanolamine ratio increase at high concentrations, but Ca2+ helped maintain normal levels. The acyl chain length and unsaturation of lipids remained unaffected, suggesting Cd2+ doesn't alter acyl chain structure of lipids. These findings suggest that Cd2+ may affect the growth of mycelia by inhibiting the synthesis of membrane lipids, particular the synthesis of phosphatidylethanolamine, providing novel insights into the mechanisms of Cd2+ stress in fungi and the role of Ca2+ in mitigating the stress. • Cd2+ in growth media inhibits mycelial growth, with stronger effects at higher concentrations. • Ca2+ mitigates Cd2+-induced growth inhibition in mycelium in a dose-dependent manner. • Cd2+ reduces membrane lipids and alters lipid composition, while Ca2+ counteracts the changes. • Phosphatidylethanolamine is most affected, the acyl chains of eight classes remain unaffected. [ABSTRACT FROM AUTHOR]

In recent years, ion-imprinted polymers have gained significant attention and are extensively utilized owing to their high selectivity toward target ions. For this research, Pb(II) ions were used as the template ions, polyamide-amine dendrimers as the curing agent, epoxy resin as the carrier and combined with ion-imprinting technique in the preparation of Pb(II)-imprinted polymer (Pb(II)-IIP). Systematic adsorption experiments were used to investigate the impact of the adsorbent on the adsorption performance of Pb(II) ions. The composition of the adsorbent was further studied by FT-IR, SEM and other characterization techniques. The maximal adsorption capacity at pH = 5 and T = 318 K was calculated to be 138.8 mg/g. In the coexistence of multiple ions, the Pb(II)-IIP showed high selectivity for Pb(II) adsorption. Pb(II) was still removed at a rate of more than 91% after five cycles of experiments, indicating good reusability. [ABSTRACT FROM AUTHOR]

This study describes the synthesis of a novel meso/magnetic adsorbent based on chitosan nanocomposite hydrogel to remove heavy metal ions from aqueous solutions. The meso/magnetic nanocomposite hydrogel was designed from the blending of chitosan and cellulose bio-polysaccharides in the presence of magnetic Laponite RD (nanoclay) nanoparticles (Fe3O4/La). Fe3O4/La nanoparticles were obtained by the in-situ co-precipitation method. The nanocomposite hydrogel was characterised by FT-IR, XRD, VSM, TGA, TEM, FE-SEM, and BET techniques. Several important parameters influence the adsorption of Cu (II), Hg (II), Co (II), and Ni (II) ions in the aqueous solution such as contact time, pH, temperature, and effect of metal concentration with single and multi-metal systems were investigated systematically by batch experiments. Compared with the adsorption of other ions, adsorption of the Hg (II) ions on the chitosan/cellulose/laponite RD nanocomposite hydrogel was showed high selective and high-efficient. The adsorption process of Hg (II) ions has shown best correlated to the Langmuir isotherm and pseudo-second-order models, respectively. The maximum adsorption capacity of Hg (II) ions was 579.8 mg/g. The thermodynamic data showed that the adsorption process was spontaneous, favourable, and endothermic. [ABSTRACT FROM AUTHOR]

The environmental implications of tire wear particles (TWPs) have been extensively studied. One notable concern associated with nano-sized TWPs is their potential role as carriers that enhance the spread of co-occurring pollutants, especially in the context of aging processes. This study demonstrated how exposure to acid, ultraviolet (UV) radiation, or ozone (O3) induced alterations in the physico-chemical properties of TWPs, consequently increasing their mobility within saturated sand environments. In cotransport cases, both original TWPs and aged TWPs inhibited the transport of Cd2+ and Ni2+ in different degrees, whereas no obvious changes in their intrinsic mobilities. The contaminant-mobilizing ability of TWPs followed the order of original TWPs/UV-TWPs < H+-TWPs < O3-TWPs. Experimental results and model-based analyses indicated the important role of mobility, adsorption affinity and desorption hysteresis in the cotransport of TWPs and heavy metals. In comparison with original TWPs, the adsorption affinity of H+-TWPs and O3-TWPs for Cd2+/Ni2+ decreased, while that of UV-TWPs was similar to original TWPs. Simultaneously, the desorption rates of TWPs decreased to different extents after aging. The results of this study provide valuable insights on the fate of aged TWPs and their interactions with heavy metals in the natural environment, and help assess the environmental behavior and contaminant mobilization capacity of TWPs, especially considering the distinct effects of different aging processes. It is imperative to emphasise the necessity for targeted management strategies to transport the environmental impacts of TWPs, particularly as they age and interact with heavy metals. [ABSTRACT FROM AUTHOR]

Industrial wastewater often contains highly carcinogenic and mutagenic inorganic pollutants and harmful heavy metals such as Chromium (Cr), which are highly reactive and toxic, even at low concentrations. Efficient remediation or removal of Chromium is necessary to prevent its adverse impacts on humans and the environment. We have employed biofilm grown on a glass surface as a sustainable tool to reduce water's Cr(VI) levels. We studied biofilm formation using four different bacterial strains. Among those, Pseudomonas aeruginosa was selected based on its biofilm formation ability, estimated by qualitative and quantitative means. Maximum biofilm formation was observed on a glass surface using tryptone soya broth (TSB) at 37 °C and pH 7.5. The biofilm was characterized using Field Emission Scanning Electron Microscopy (FESEM) and stereo microscopy. The biofilm tolerated up to 10 ppm of chromium supplementation in the culture medium. The Cr(VI) concentration was determined using a UV–Vis spectrophotometer, and total chromium content was obtained using Inductively Coupled Plasma—Optical Emission Spectrometry (ICP-OES). With preformed biofilm on glass, Cr(VI) concentration was reduced by 97% within eight hours with a reduction rate of 12.27% per hour. In comparison to biofilm during formation, preformed biofilm gave better results. The Field Emission Scanning Electron Microscopy (FESEM)—Energy Dispersive Spectroscopy (EDS) (FESEM-EDS) analysis depicted very minimal Cr(VI) adsorption into the cells, indicating the reduction of more harmful Cr(VI) to less toxic Cr(III). The present findings can lead to the development of an efficient treatment strategy for chromium-contaminated water. [ABSTRACT FROM AUTHOR]

The presence of heavy metals in aqueous media threatens environmental safety and human health, so it is necessary to effectively remove them from wastewater. Through a simple preparation method, lignin (LS) and montmorillonite (MMT) were successfully prepared into efficient biosorbents. The prepared hydrogel not only has water absorption and pH-responsive swelling properties, but also has good removal effect on heavy metals. The maximum adsorption capacity of Cd (II) ions was 587.14 mg / g. The maximum adsorption capacity of Zn (II) ions was 297.13 mg / g.The results of principal component analysis show that the adsorption process of heavy metals is in good agreement with different kinetic and isotherm models. The adsorption mechanism is proposed, which is related to the chemical properties between adsorbents. This study provides a promising and sustainable lignin-based composite hydrogel. [ABSTRACT FROM AUTHOR]

Environmental impacts related to arsenic (As) contamination are a persistent issue of particular interest in Latin American countries with increasing mining activities. In Ecuador, the redefinition of public policies to promote the increase in mining since 2008 has led to a significant rise in the presence of this heavy metal in rivers and effluents, sometimes exceeding the 0.1 mg L−1, limit recommended by Ecuadorian Environmental Regulations. This study aimed to evaluate the sublethal effects through the detection of biochemical biomarker changes (Catalase, Antioxidant capacity by FRAP, and Glutathione S-transferase) generated in larvae of Nectopsyche sp following prolonged exposure to different concentrations of As (C1 = 0.05 mg L−1, C2 = 0.1 mg L−1, C3 = 0.8 mg L−1) in a controlled environment, emulating the maximum limits allowed by current Ecuadorian legislation. While As concentration levels in water increased, so did levels in the tissue of Nectopsyche sp specimens. On the other hand, behavioral parameters (mortality and mobility) did not show differences in either time or As concentrations. However, both Catalase and Antioxidant capacity by FRAP levels tended to decrease with increasing As concentration, and in both cases, the differences were significant. Additionally, Glutathione S-transferase activity did not increase significantly. These results preliminarily demonstrate that biochemical responses change with varying As concentrations in Nectopsyche sp and are affected at behavioral and biochemical levels produced by the As at chronic levels. [ABSTRACT FROM AUTHOR]

Cadmium (Cd), a widely distributed environmental pollutant in agroecosystems, causes negative effects on crops and herbivores through bottom-up processes. The gut microbial community of an insect can play a critical role in response to metal stress. To understand how microbiota affect the stress responses of organisms to heavy metals in agroecosystems, we initially used 16S rRNA sequencing to characterize the larval gut microbiota of Chilo suppressalis, an important agricultural pest, exposed to a diet containing Cd. The species richness, diversity, and composition of the gut microbial community was then analyzed. Results revealed that while the richness (Chao1 and ACE) of gut microbiota in larvae exposed to Cd was not significantly affected, diversity (Shannon and Simpson) was reduced due to changes in species distribution and relative abundance. Overall, the most abundant genus was Enterococcus, while the abundance of the genera Micrococcaceae and Faecalibaculum in the control significantly superior to that in Cd-exposed pests. Phylogenetic investigation of microbial communities by the reconstruction of unobserved states (PICRUSt) showed that the intestinal microorganisms appear to participate in 34 pathways, especially those used in environmental information processing and the metabolism of the organism. This study suggests that the gut microbiota of C. suppressalis are significantly impacted by Cd exposure and highlights the importance of the gut microbiome in host stress responses and negative effects of Cd pollution in agroecosystems. [ABSTRACT FROM AUTHOR]

The present study describes synthesis of Salvia species (S. plebeia and S. moorcroftiana) mediated gold nanoparticles using deionized water and ethanol as extracting solvents. The study further quantify total phenolic and flavonoids content, assessment of antioxidative and microbial inhibitory potential, and catalytic and sensing abilities of the synthesized gold nanoparticles in dyes degradation and heavy metals sensing. Quantifying the phenolic content, ethyl acetate extract of S. moorcroftiana exhibited the high content (327.2 mg gallic acid equivalent per gram) followed by ethanol and methanol extracts. However, S. plebeia was comparatively low in total phenolic content. In total flavonoid content quantification, methanol and ethanol extracts of S. moorcroftiana exhibited statistically same content (406.9 mg quercetin equivalent per gram and 400.8 mg quercetin equivalent per gram, respectively) followed by ethyl acetate extract. In synthesis of Salvia aqueous mediated gold nanoparticles, ratio/concentration (extract/salt solution) of 1:20 resulted in the most intense and sharp peak at 520–530 nm, whereas ethanolic extract produced reasonable and prominent nanoparticles under sunlight with 1:5 to 1:10 concentration. Assessing the antioxidant and antibacterial activities, Salvia extracts and the nanoparticles were potent antiradical and antibacterial agents. Furthermore, the subject nanoparticles have shown reasonable degradation of Congo red, methylene blue, and methyl orange, and sensing property to detect lead(II) in river water. Hence, Salvia species and the nanoparticles could be used in curing diseases involving free radicals, infections, and remediation of environmental contamination with dyes and lead(II). [ABSTRACT FROM AUTHOR]

The issue of heavy metal pollution is a critical global concern that requires urgent solution. However, conventional heavy metal adsorbents are too costly to be applied in large-scale engineering. In this study, adsorption behavior and mechanism of sintering red mud (RM-A) and bayer red mud (RM-B) for heavy metals were investigated to address the disposal of red mud as industrial waste and remediation of heavy metal pollution. Batch adsorption experiments were conducted to explore the adsorption performances of RM-A and RM-B under various conditions. Characterization of RM-A and RM-B before and after adsorption by XRD, FTIR and SEM-EDX was applied to investigate the specific adsorption behavior and mechanism. Adsorption experiments of both RM-A and RM-B fitted pseudo-second-order kinetic model and Langmuir isotherm model, with estimated maximum adsorption capacity of 21.96 and 25.19 mg/g for Cd2+, 21.47 and 26.06 mg/g for Cu2+ and 55.47 and 59.65 mg/g for Pb2+, respectively. Precipitation transformation of calcite was the primary adsorption mechanism for RM-A, whereas ion exchange of cancrinite, surface coordination compounds of hematite and minor precipitation transformation of calcite accounted for the adsorption mechanism for RM-B. Overall, RM-A and RM-B exhibited best adsorption performance for Pb2+, with RM-B showing greater adsorption capacity attributed to its higher specific surface area. This study compared the adsorption properties of RM-A and RM-B for the first time and demonstrated that both red muds can be effectively applied to remove heavy metals, thereby contributing to the sustainable industrial waste management and resourceful reuse. [ABSTRACT FROM AUTHOR]

Changing climate imposes abiotic stress factors, including salinity, flood, drought, high and low temperature, and light as well as heavy metals on medicinal plants. Plants respond to stress in terms of growth and biosynthesis of metabolites. The rhizomatous genus Curcuma has been extensively used in traditional or folk medicine worldwide and its therapeutic potential relies on its phyto-constituents. A discrete array of literature depicts negative effects on growth and alterations in yield of secondary metabolites under abiotic stress. However, one complete and precise document on the response of Curcuma spp. towards abiotic stress and their molecular mechanism is lacking. Hence, this review has been prepared by pulling together the published information on the abiotic stress response as well as the future research prospects on the Curcuma spp. along with other related rhizomatous plants of the family Zingiberaceae, to obtain prospective clues on possible responses of these medicinally potential species in the verge of changing climate. We have also highlighted the stress mitigation strategies employed by these plants in the light of available literature and by comparing with information on related species of Zingiberaceae family. We have focused on the urgency of multiomics approaches to find out the genetic and biochemical strategies of Curcuma spp. to cope with stress as well as emphasized for conservation of rare and endangered species of Curcuma. This review will be helpful for plant physiologists, farmers, pharmaceutical industries, and policy makers, to implement better plans and policies regarding uninterrupted commercial yield of Curcuma secondary metabolites in changing climate. [ABSTRACT FROM AUTHOR]

Tea leaves and their infusion have been interested in the populations because of their therapeutic and relaxing effects. However, tea plant is prone to heavy metals' bioaccumulation. Regarding the high consumption of tea infusion, concentration of arsenic, cadmium, and lead in black tea infusion was determined by inductively coupled plasma mass spectrometry. Tea infusion was prepared by addition of 45 mL deionized water to 1 g tea leaves followed by heating at 90°C for 10 min. After analysis, carcinogenic and noncarcinogenic risks of heavy metals were investigated by Monte Carlo simulation in two age groups of children and adults younger and older than 15 years old, respectively. According to the results, Hazard Quotient (HQ) of three heavy metals in both children and adults was equal and lower than 0.01. Furthermore, incremental lifetime cancer risk (ILCR) of arsenic in Iranian black tea consumers (<1.5 × 10−6) and lead in all consumers (about 2.55 × 10−7) was within the acceptable range introduced by US EPA (≤10−6). ILCR of arsenic in children and adults consuming foreign tea infusion was within the range of 10−6–10−4. Our further investigation revealed that the highest area (75%–85%) of cumulative frequency distribution for arsenic ILCR in foreign tea consumers was related to ILCR ≤10−5 which is the acceptable range determined by the World Health Organization. Therefore, there was no serious concern about the intake of heavy metals by tea infusion in Iranian children and adults. [ABSTRACT FROM AUTHOR]

One of the goals of sustainable agricultural production is to avoid soil contamination by elements defined as trace metals (TMs). The aim of this study was to assess the long-term impact of the use of pig slurry (PS) and NPK mineral fertilizers on the soil content of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn). In a 9-year crop rotation, PS was used three times only before root crops. The same four levels of NPK doses (N0P0K0, N1P1K1, N3P2K2, N4P2K2) were applied to both plots with and without PS. Soil samples were collected in early spring from topsoil (0–0.3 m) and subsoil (0.3–0.6 m). Three forms of TMs were determined in the soil: pseudo-total (Aqua regia); bioavailable (Mehlich 3 method) and readily bioavailable (mobile) forms (1 M NH4NO3). The tested factors did not have a significant impact on the Cd, Cu and Pb content, regardless of the form analyzed and the soil depth. PS application significantly increased the content of bioavailable forms of Zn regardless of the year, and the content of pseudo-total Zn only in the sugar beet year, i.e. after manure application. Increasing NPK doses increased the content of mobile Zn in the topsoil, especially in PS plots. A tendency to accumulate mobile forms of Cd and Pb was also observed on NPK-fertilized plots. Thus, long-term application of high NPK doses may increase the risk of contamination of the food chain with these metals. The content of mobile Cd and Zn was positively related to the content of total nitrogen in the soil and negatively related to pH. [ABSTRACT FROM AUTHOR]

Objective The primary objective of this study was to investigate the potential correlation between the presence of 22 metals in urine and the risk of developing gallstones in Bouyei population in qiannan region, ultimately aiming to furnish a scientific foundation for early preventative measures and targeted interventions. Methods From July 2018 to August 2019, a baseline survey was conducted among residents aged 30 to 79 years in Qiannan Bouyei and Miao Autonomous Prefecture using multistage stratified cluster sampling, including questionnaires, physical examination and ICP-MS to detect urine metal concentration. Urinary metal concentrations were divided into four groups (Q1, Q2, Q3, Q4), and binary logistic regression model was used to analyze the relationship between single metal and gallstone risk. At the same time, the dose-response relationship between metal concentration and gallstone risk was investigated by using restricted cubic splines. Results The gallstone detection rate of Bouyei population was 8.825%. After adjusting for covariates, binary logistic regression analysis revealed that in the male group, compared to the Q1 group, there was a positive association between gallstone risk and selenium in the Q2 group (OR=1.894, 95%CI: 1.046-3.431), Se in the Q3 group (OR=1.912, 95%CI: 1.053-3.472), and Fe in the Q3 group (OR=1.827, 95%CI: 1.040-3.210). In the female group, Al in the Q3 group (OR=1.460, 95%CI: 1.050-2.028) was positively associated with gallstone risk, while Na in the Q4 group (OR=0.654, 95%CI: 0.452-0.948) was negatively associated with gallstone risk, with a dose-response relationship observed. Conclusion There is a significant correlation between the concentration of certain metals in urine and the risk of gallstones. In the Bouyei female population in particular, urinary aluminum and urinary sodium concentrations have a significant impact on gallstone formation, providing possible directions for future prevention and treatment strategies. [ABSTRACT FROM AUTHOR]

This review article details the advancements in detecting heavy metals in aquatic environments using remote sensing methodologies. Heavy metals are significant pollutants in aquatic environment, and their detection and monitoring are crucial for predicting water quality. Traditional in situ water sampling methods are time-consuming and costly, highlighting the advantages of remote sensing techniques. Analysis of the reflectance and absorption characteristics of heavy metals has identified the red and near-infrared bands as the sensitive wavelengths for heavy metal detection in aquatic environments. Several studies have demonstrated a correlation between total suspended matter and heavy metals, which forms the basis for retrieving heavy metal content from TSM data. Recent developments in hyperspectral remote sensing and machine (deep) learning technologies may pave the way for developing more effective heavy metal detection algorithms. [ABSTRACT FROM AUTHOR]

Wastewater contaminated with cadmium is a concern because of its toxicity, persistence, and bioaccumulation to the environment, ecosystem, and human health, so it is required to remove cadmium(II) ions before releasing them to receiving water. Banana powder beads (BPB), banana powder doped ZnO beads (BPZB), banana powder doped MgO beads (BPMB), and banana powder doped ZnO + MgO beads (BPZMB) were synthesized as the novel cadmium adsorbents, and their characterizations, cadmium adsorption performances, cadmium adsorption patterns and mechanisms, thermodynamic study, and reusability were investigated. BPMB had the highest specific surface area of 16.60 m2/g and the smallest pore size of 1.69 nm than other materials. BPB was an amorphous structure, whereas BPZB, BPMB, and BPZMB were crystalline structures presenting their specific metal oxide peaks of ZnO or MgO. They were coarse surfaces and had a spherical shape consisting of C, O, Ca, Cl, and Na. Their main functional groups were O–H, C–H, C=O, C–O, and N–H. The points of zero charge of BPB, BPZB, BPMB, and BPZMB were 5.37, 6.75, 9.87, and 9.43. The cadmium removal efficiencies of BPB, BPZB, BPMB, and BPZMB were 89.18%, 96.62%, 99.59%, and 97.85%, and their qm values were 90.09, 232.56, 454.55, and 303.03 mg/g, respectively. Thus, the metal oxide helped to improve material efficiency, especially MgO. The Freundlich and pseudo-second-order kinetic models were good fit models for describing their adsorption patterns and mechanisms. The increasing temperature affected to decrease their cadmium adsorptions. They could be reused in more than 3 cycles of more than 73% of cadmium adsorption. The electrostatic interaction played an important role in describing their cadmium adsorptions. Therefore, BPBM was a good cadmium adsorbent for application in industrial wastewater treatment since it had a higher performance of cadmium adsorption than other materials. [ABSTRACT FROM AUTHOR]

The development of heavy metals, particularly chromium (Cr)-tolerant crop cultivars, is hampered due to lack of understanding of the mechanisms behind Cr stress tolerance. In this study, two Brassica napus cultivars, ZS758 and ZD622, were compared for Cr stress resistance by using the chlorophyll a fluorescence technique and biochemical characteristics. In both cultivars, Cr stress dramatically decreased PSII and PSI efficiency, biomass accumulation, and antioxidant enzyme levels. Although, cultivar ZS758 showed reduction in oxidative stress by decreasing the production of reactive oxygen species (ROS) in terms of reduced H2O2 and MDA content and increased enzymatic activities of key antioxidants enzymes including SOD, APX, CAT, and POD activities that play a crucial role in the regulation of numerous transcriptional pathways involved in oxidative stress responses. Higher non-photochemical quenching (NPQ) and QY were found in tolerant ZS758 cultivar under Cr stress, indicating that tolerant cultivar had a greater capacity to preserve PSII activity under Cr stress by enhancing heat dissipation as a photo-protective component of NPQ. Lower PSI activity and electron transfer from PSII were confirmed by lower PSI efficiency and higher donor end limitation of PSI in both rapeseed cultivars. The Cr concentration was greater in the ZD622 as compared to ZS758, which affected the mineral nutrients profile and damaged the cellular ultrastructure and related gene expression levels. However, current study suggest that cultivar ZS758 is more resistant to Cr stress than ZD622 due to improved metabolism and structural integrity and Cr stress tolerance that is linked with the increased PSII activity, NPQ, and antioxidant potential; these physiological characteristics can be exploited to select cultivars for Cr stress tolerance. [ABSTRACT FROM AUTHOR]

The co-contamination of dyes and heavy metal ions often used as mordants poses potential risks to environment and public health, and is a challenging problem that needs to be solved in water treatment. Meanwhile, improving the solid–liquid separation capability of adsorbents is of great significance for the application of adsorption technology. Herein, amidation modified hollow composite microspheres were prepared using hollow glass microsphere (HGM) as matrix through hydrolysis and condensation of silane coupling agent (A-1100) and subsequent amidation reaction. The material (HGMNE) not only exhibited good adsorption performance for DB86 and Ni2+ but also had stable self-floating capability. The adsorption of DB86 by HGMNE is mainly carried out by the electrostatic interaction between positively charged quaternary amine nitrogen and negatively charged DB86, while the adsorption of Ni2+ is achieved by the carboxyl group in EDTA group through complexation interaction to adsorb Ni2+ to form Ni complex. This research not only is devoted to the utilization of HGMNE to achieve the co-removal of DB86 and Ni2+ and flexible self-floating solid–liquid separation but also verifies the feasibility and applicability of the modification method of introducing organic adsorption functional groups through amidation reaction, so as to expand the preparation path of HGM-based adsorbents. [ABSTRACT FROM AUTHOR]

Elevated concentrations of metals in rivers can pose significant risks to human health. Consequently, it is essential to monitor metal levels in river water to minimize human exposure, particularly through consumption of harvested fish and other uses. This study examined the water quality of the Ona River in Ibadan, Nigeria. Seven potentially toxic elements (PTEs), namely Fe, Cu, Mn, Zn, Pb, Cd, Cr and four macronutrients: Mg, Na, K, Ca were investigated. Surface and pore water samples were collected from six sampling points during the peak of the dry and the rainy seasons. These were analyzed according to standard procedures and processed using the Simple Fuzzy Classification (SFC) model with four classes. The results revealed that the PTEs: Fe, Pb, Cd, Cr, and Mn were detected above guideline limits in several sampling points, indicating possible contamination from anthropogenic sources. Simple fuzzy classification puts the quality of water in the investigated portion of the river in the range of 67.4–88.5% in the C1 (pristine) category during the dry season and 61.9–88.6% in C1 (pristine) during rainy season. However, there were membership functions of up to 58.7 and 63.2; 61.2 and 75.4 as well as 44.3 and 43.5% in C2, C3, and C4 categories (contaminated, polluted and extremely polluted, respectively) during the first and second sampling, respectively. Due to the high concentrations of toxic and bioaccumulative metals in the river, efforts should be made to control the discharge of pollutants into the river. These will prevent human health exposure risks tendencies for various uses, including fish production. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Rice is often rotated with dryland crops to produce sufficient foodstuff, as rice is the main food crop of humans. In order to verify whether under the intensive rice‐based cropping system, high yield and good quality of rice can be achieved simultaneously to ensure food security. Five long‐term paddy–upland rotations – wheat–rice (WR), rapeseed–rice (RR), garlic–rice (GR), broad beans–rice (BR) and potato–rice (PR) – were conducted from 2014 to investigate rice yield, along with the profiling of 24 elements in rice grain.Mg, Zn, Cu, As, Mo and Sb concentrations were highest in the aleurone layer, and Ag and Cd concentrations showed little variation among different parts of the rice grain. Al, Ti, V, Si, Fe and Tl concentrations in the endosperm under GR were higher, while the Se concentration under PR was the highest. Furthermore, the yield of GR and PR were higher than the other three rotations with N supplementation, and the sustainable yield index of PR and WR were larger than 0.8.When we consider the concentration of toxic (As, Cd and Pb) and nutrient elements (Ca, Fe, Zn, Se, Cu and Mg) in the endosperm and grain yields, PR can simultaneously achieve high yield, high nutrition and low toxicity with different nitrogen treatments. Here we provide novel insights regarding the selection of rice‐based cropping systems, focused on producing nutritious and safe rice with high grain yield. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Chitosan (CTS) is recognized for enhancing a plant’s resilience to various environmental stresses, such as salinity and drought. Moreover, salicylic acid (SA) is acknowledged as a growth regulator involved in addressing metal toxicity. However, the effectiveness of both compounds in mitigating Cr-induced stress has remained relatively unexplored, especially in the case of Aconitum napellus, a medicinally and floricultural important plant. Therefore, the primary objective of this study was to investigate the potential of CTS and SA in alleviating chromium (Cr)-induced stress in A. napellus. To address these research questions, we conducted a controlled experiment using potted plants to evaluate the individual and combined impacts of CTS and SA on plants exposed to Cr stress. Foliar application of CTS (0.4 g/L) or SA (0.25 mmol/L) led to significant improvements in the growth, chlorophyll content, fluorescence, and photosynthetic traits of A. napellus plants under Cr stress. The most notable effects were observed with the combined application of CTS and SA, resulting in increases in various morphological parameters, such as shoot length (2.89% and 7.02%) and root length (27.75% and 3.36%) under the Cr 1 and Cr 2 treatments, respectively. Additionally, several physiological parameters, such as chlorophyll a (762.5% and 145.56%), chlorophyll b (762.5% and 145.56%), carotenoid (17.03% and 28.57%), and anthocyanin (112.01% and 47.96%) contents, were notably improved under the Cr 1 and Cr 2 treatments, respectively. Moreover, the combined treatment of CTS and SA improved the fluorescence parameters while decreasing the levels of enzymatic antioxidants such as catalase (27.59% and 43.79%, respectively). The application also notably increased osmoprotectant parameters, such as the total protein content (54.11% and 20.07%) and the total soluble sugar content (78.17% and 49.82%) in the leaves of A. napellus in the Cr 1 and 2 treatments, respectively. In summary, these results strongly suggest that the simultaneous use of exogenous CTS and SA is an effective strategy for alleviating the detrimental effects of Cr stress on A. napellus. This integrated approach opens promising avenues for further exploration and potential implementation within agricultural production systems.Key message: This explains the interactive role of chitosan and salicylic acid in alleviating chromium stress in Aconitum napellus. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Wheat is one of major sources of human cadmium (Cd) intake. Reducing the grain Cd concentrations in wheat is urgently required to ensure food security and human health. In this study, we performed a field experiment at Wenjiang experimental field of Sichuan Agricultural University (Chengdu, China) to reveal the effects of FeCl3 and Fe2(SO4)3 on reducing grain Cd concentrations in dwarf Polish wheat (Triticum polonicum L., 2n = 4x = 28, AABB). Results: Soil application of FeCl3 and Fe2(SO4)3 (0.04 M Fe3+/m2) significantly reduced grain Cd concentration in DPW at maturity by 19.04% and 33.33%, respectively. They did not reduce Cd uptake or root-to-shoot Cd translocation, but increased Cd distribution in lower leaves, lower internodes, and glumes. Meanwhile, application of FeCl3 and Fe2(SO4)3 up-regulated the expression of TpNRAMP5, TpNRAMP2 and TpYSL15 in roots, and TpYSL15 and TpZIP3 in shoots; they also downregulated the expression of TpZIP1 and TpZIP3 in roots, and TpIRT1 and TpNRAMP5 in shoots. Conclusions: The reduction in grain Cd concentration caused by application of FeCl3 and Fe2(SO4)3 was resulted from changes in shoot Cd distribution via regulating the expression of some metal transporter genes. Overall, this study reports the physiological pathways of soil applied Fe fertilizer on grain Cd concentration in wheat, suggests a strategy for reducing grain Cd concentration by altering shoot Cd distribution. [ABSTRACT FROM AUTHOR]

The Saimaa ringed seal (Pusa hispida saimensis) is a subspecies of ringed seal, landlocked in Lake Saimaa, Finland. The small population of less than 500 seals is facing many human-induced threats, including chemical contaminants. Mercury, in particular, has previously been suggested to be one of the chemicals affecting the viability of this endangered population. We analysed mercury concentrations from placentas and lanugo pup tissues (blubber, brain, kidney, liver, and muscle) to determine current prenatal exposure levels. These pups were found dead in or near birth lairs and were less than 3 months old. Additionally, we used threshold values available in the literature to estimate the potential mercury toxicity to the Saimaa ringed seal. We also determined selenium concentrations for its potential to alleviate the adverse effects of mercury. We further supplemented our study with brain samples collected from various seal age classes. These seals were found dead by either natural causes or by being caught in gillnets. The analysed chemicals were present in all tissues. For lanugo pups, mercury concentrations were the highest in the kidney and liver, whereas the highest selenium to mercury molar ratio was observed in placentas. The toxicity evaluation suggested that, in severe cases, mercury may cause adverse effects in lanugo and older pups. In these cases, the selenium concentrations were low and selenium to mercury ratio was below 1:1 threshold ratio and thus unlikely to provide adequate protection from the adverse effects of mercury. Furthermore, adverse effects are more likely to occur in adult seals, as mercury bioaccumulates, leading to higher concentrations in older individuals. Placental mercury concentrations correlated to those in the livers and muscle tissues of lanugo pups. This, together with the fact that placentas can be collected non-invasively and in good condition, provides a potential novel method for biomonitoring mercury exposure in Saimaa ringed seals. [ABSTRACT FROM AUTHOR]

Microorganisms remain in water from various sources after desalination and other treatments, posing health risks. We explored alternative natural disinfection agents, focusing on grape seed extract (GSE). We collected local grape seeds in Saudi Arabia and analyzed their chemical components. Using gas chromatography–mass spectrometry and inductively coupled plasma mass spectrometry, we identified essential phytochemicals in the GSE, including polyphenols, flavonoids, and alkaloids. Notably, the GSE was free from bacteria and heavy-metal contamination and rich in beneficial nutrient metals. We conducted qualitative analyses on local water and urine samples to detect bacterial infections, heavy metals, and minerals. To assess GSE's antibacterial potential, we performed molecular docking analysis. Our results reveal a strong binding energy between GSE and bacterial protein receptors, parallel to that of standard antibiotics. Additionally, the results of the laboratory pilot investigations align with those of computational analyses, confirming GSE's efficacy. Agar well diffusion tests demonstrated significantly greater zones of inhibition for the crude oil extract compared with both diluted GSE and the positive control against the bacteria detected in the water and urine samples. Furthermore, we identified contamination by four bacterial strains and heavy metals in water samples and female urine samples, highlighting the need for effective water disinfectants. GSE shows promise as a safe and potent natural water disinfectant. [ABSTRACT FROM AUTHOR]

The exogenous application of oxalic acid is a potential approach to amplifying phytoremediation performance on Cd-contaminated soils. However, few studies explore the optimal oxalic acid application regime from a perspective of coupling different concentrations and timings to maximize Cd removal rate. Given this, a pot experiment was conducted using oil sunflower (Helianthus annuus L.) as the test plant. Oxalic acid was added to the pots at concentrations of 1, 2, 3, 4, 5, and 6 mmol/kg at 20, 30, 40, and 50 days after emergence. A control (CK) without exogenous oxalic acid was also included. We examined the discrepancies in various soil Cd forms, sunflower height, plant non-protein thiol (NPT) levels, and soil Cd remediation efficiency under different oxalic acid application regimes. The results showed that applying oxalic acid at a concentration of 4 mmol/kg reduced the proportion of Fe-Mn oxide Cd and organic Cd compared to the control (CK), while increased the proportion of available Cd. The optimal application time is 30 or 40 days after emergence. The addition of exogenous oxalic acid promoted the growth of sunflowers, with the greatest increase in plant height observed when 4 mmol/kg oxalic acid was applied at 30 days after emergence. Exogenous oxalic acid enhanced the absorption of Cd by sunflower roots, with the total Cd accumulation in roots, stems, and leaves being higher than in the control (CK). When 4 mmol/kg oxalic acid was applied at 30 days after emergence, the total Cd accumulation in roots, stems, and leaves was highest. Under different application times and concentration levels of oxalic acid, Cd accumulation was highest in roots, followed by leaves, with stems showing the lowest accumulation. The NPT content in each part is as follows: root > stem > leaf. Applying 5 mmol/kg oxalic acid after 30 days of sunflower emergence resulted in relatively higher total NPT content in roots, stems, and leaves compared to the control (CK). The TOPSIS model was used for comprehensive evaluation, which showed that 4 mmol/kg oxalic acid application at 30 days after emergence could be used as the optimal oxalic acid application regime for phytoremediation. These findings indicate that the addition of oxalic acid effectively promoted the absorption of Cd by sunflower and increased the efficiency of Cd removal from the rhizosphere soil, with the optimal removal of soil Cd achieved by applying oxalic acid at a concentration of 4 mmol/kg 30 days after the emergence of oilseed sunflower seedlings. [ABSTRACT FROM AUTHOR]

Pesticides and heavy metals are considered as potent contaminants in aquatic environment. Both contaminants are sourced into the aquatic ecosystems by various types of anthropogenic as well as natural practices. Such types of aquatic contamination drastically affect the normal activity of associated living organisms particularly fish. Both the pesticides and heavy metals toxicity cause several negative effects on fish growth, physiology, immune response, reproduction, embryonic and larval development as well as different histopathology of major organs including fish gill, kidney, liver, gonads, and intestine. Besides, the consumption of contaminated fish poses a serious health concern to associated consumers. Considering these serious issues, the current review is designed to investigate the toxic effects of pesticides and heavy metals on different aspects of fishes along with their possible sources, major types, and mode of action as well as role of medicinal herbs to mitigate their toxicity. [ABSTRACT FROM AUTHOR]

This study examined the concentrations of seven heavy metals (Pb, Cu, Zn, Cr, Cd, Ni, and Mn) in the muscle tissue of six commonly consumed fish species (Cyprinus carpio, Labeo rohita, Wallagu attu, Hypophthalmicthys molitrix, Channa punctuate, and Puntius sophore) from the River Indus in the Mianwali district Pakistan. Samples were collected during both pre-monsoon and post-monsoon seasons to assess the potential human health risks associated with these heavy metals. The levels of metals were measured using atomic absorption spectroscopic analysis. The results showed varying concentrations of heavy metals in the fish samples (mg/kg), ranging from 10.17-2.06 for Pb, 41.83-12.54 for Cu, 417.04-41.93 for Zn, 2.06-0.46 for Cr, 0.86-0.08 for Cd, 4.33-1.43 for Ni, and 50.16-8.74 for Mn. Notably, metal concentrations were generally higher during the pre-monsoon season, with Pb consistently exceeding standard limits in the muscle tissue of all fish species. ANOVA analysis revealed significant variations in heavy metal concentrations among different fish species. While the current consumption rate poses no significant health risks, ongoing monitoring of heavy metal concentrations in fish and their environmental sources is crucial to ensure consumer safety and sustainable aquatic ecosystems. [ABSTRACT FROM AUTHOR]

This study unveiled the cadmium phytoremediation potential and its augmentation using 6-Benzylaminopurine in Strobilanthes alternata. Cadmium stress was provided by applying 250 mg/kg cadmium chloride in soil and 25 ppm of 6-BAP (25 ml) was administered to the plants as foliar spray. The results revealed high bioconcentration factor (BCF) (18.82 ± 0.54) and low translocation factor (TF) values (0.055 ± 0.002) for the plant based on which we strongly recommend S. alternata as a promising candidate for Cd phytoremediation. The phytostabilization potential of the plant was further enhanced by applying 6-BAP, which augmented its BCF to 22.09 ± 0.64 and reduced the TF to 0.038 ± 0.001. Cd toxicity caused a reduction of plant growth parameters, root volume, adaxial-abaxial stomatal indices, relative water content, tolerance index, moisture content, membrane stability index, and xylem vessel diameter in S. alternata. However, Cd + 6-BAP treated plants exhibited an increase of the same compared to Cd-treated plants. FTIR analysis of Cd + 6-BAP treated plants revealed increased deposition of hemicellulose, causing enhanced retention of Cd in the root xylem walls, which is largely responsible for increased phytostabilization of Cd. Therefore, 6-BAP application in S. alternata can be exploited to restore Cd-contaminated areas effectively. STATEMENT OF NOVELTY: The research paper "6-Benzylaminopurine Mediated Augmentation of Cadmium Phytostabilization Potential in Strobilanthes alternata" has established the Cd phytostabilization potential of the plant Strobilanthes alternata and also identified the role of 6-BAP in augmenting the Cd phytoremediation potential of this plant for the very first time. The physiological and anatomical changes in relation to the applied stress signals were also studied for the first time in S. alternata. [ABSTRACT FROM AUTHOR]

The industrial world exposes living organisms to a variety of metal pollutants. Here we investigated whether such elements affect G-rich sequences susceptible to fold into G-quadruplex (GQ) structures. Thermal stability and conformation of these oligoncleotides was studied at various molar ratios of a variety of heavy metal salts using thermal FRET, transition-FRET (t-FRET) and circular dichroism. Metal ions affected the thermal stability of the GQs to different extents; some metals had no effect on T m while other metals caused small to moderate changes in T m at 1:1 or 1:10 molar ratio. While most of the metals had no major effect, Al3+, Cd2+, Pb2+, Hg2+ and Zn2+ altered the thermal stability and structural features of the GQs. Some metals such as Pb2+ and Hg2+ exhibit differential interactions with telomere, c-myc and c-kit GQs. Overall, toxic heavy metals affect G-quadruplex stability in a sequence and topology dependent manner. This study provides new insight into how heavy metal exposure may affect gene expression and cellular responses. • Heavy metal ions affect the thermal stability of the G-quadruplexes to different extents. • Al3+, Cd2+, Pb2+, Hg2+ and Zn2+ altered the thermal stability and structural features of the GQs. • Pb2+ and Hg2+ exhibit differential interactions with telomere, c-myc and c-kit G-quadruplexes. • Toxic heavy metals affect stability of G-quadruplexes in a sequence and topology dependent manner. • Heavy metal exposure may affect gene expression and cellular responses through direct DNA binding. [ABSTRACT FROM AUTHOR]

Kalmegh (Andrographis paniculata) is an important medicinal plant belonging to the Acanthaceae family and used for the treatment of many diseases. This study is focused on determining the critical limit for the cultivation of A. paniculata in sodic soil. A pot experiment was conducted with different exchangeable sodium percentages (ESPs) to determine the critical limit for the cultivation of A. paniculata in sodic soil. The critical limit, 16 ESP, was found for A. paniculata grown in sodic soil. Overall, increasing trends in N, P, K, Ca, Mg, Na, Zn, Fe, Cu, Mn, Cr, and Mo and a decreasing trend in Ni and Se were observed in all part of the plant due to increasing sodicity levels. The determination of the critical limit for the cultivation of A. paniculata in sodic soil is an important aspect of this paper. The nutrients and heavy metal profiling with the extreme levels of sodicity will be useful to study the nutrient utilization pattern for the nutrient management strategy of A. paniculata. [ABSTRACT FROM AUTHOR]

Toxic metals and metalloids pollution is a major ecological and human health issue, yet classical detection methods are limited. Here we review surface-enhanced Raman spectroscopy-based sensors using nanomaterial-based substrates for metal detection, with emphasis on substrate composition, functionalization, and assembly; metal sensing strategies; and analytical performance. Substrates include nobel metals, semiconductors, and composites. Substrate assembly can be done in solution or on solid supports. Sensing strategies comprise direct sensing, reporter recognition, reporter migration, substrate aggregation, and substrate modification. In general, the physicochemical properties of the substrates determine sensor sensitivity through electromagnetic and chemical enhancements of Raman scattering, whereas substrate surface functionalization, or lack thereof, determines sensor selectivity and the sensing mechanism. The main elements analyzed are mercury, lead, copper, arsenic, and chromium. [ABSTRACT FROM AUTHOR]

Lake Victoria is an important source of fish for domestic, regional and global market. Recently, the lake has experienced severe pollution from wastewater and industry. Winam Gulf, located on the eastern side of Lake Victoria Kenya is currently under pollution threat from multiclass pollutants including heavy metals, potentially harming human health and aquatic biodiversity. Therefore, the objective of this paper was to investigate the comparative analysis of heavy metal loading from sewage effluents and Inlet Rivers in the Winam Gulf of Lake Victoria, Kenya using appropriate standard methods. Data obtained show that Nickel average concentration 0.255 mg/l exceeding 0.07mg/l WHO acceptable standards; Lead average concentration 0.048 mg/l exceeding 0.01 mg/l WHO acceptable standard; Cadmium average concentration 0.037mg/l exceeding 0.003mg/l WHO acceptable standard. Among the rivers sampled, River Kisat showed higher concentrations of all the heavy metals analyzed than River Nyando. Heavy metal concentration of the sediment and water samples collected from the different sites were significantly different (p≤0.05). In conclusion, the concentrations of Nickel, Lead, and Cadmium in water samples exceeded WHO standards, especially in River Kisat. The study recommends that there is need to conduct routine assessment of the levels of heavy metals within the gulf, stricter enforcement of regulations governing waste water treatment and discharge and improved efficiency of wastewater treatment plants. [ABSTRACT FROM AUTHOR]

Calcium silicate hydrate (CSH) gel is the most important hydration product of cement. It influences the mechanical properties of resulting materials and plays an important role in the adsorption and immobilization of heavy metal ions. Research in the structure of CSH gel and its ability for heavy metal immobilization enables the development of tailored cement-based materials, a feature that holds significant future potential. In this study, CSH gel was synthesized under different pH and Ca/Si conditions. Structural and morphological changes in CSH gel were investigated using modern technologies. The results revealed that both pH and Ca/Si ratios were important factors influencing the structure of CSH gel. During the formation of CSH, both Cr3+ and Pb2+ can be incorporated into CSH gel, and promoting the formation of calcium hydroxide Cr3+ can also replace Si4+ in the Si-O bond. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a well-known neurotoxin with established adverse effects on the neurological functions of children and younger adults, including motor, learning, and memory abilities. However, its potential impact on older adults has received less attention. Using the zebrafish model, our study aims to characterize the dose–response relationship between environmentally relevant Pb exposure levels and their effects on changes in behavior and transcriptomics during the geriatric periods. We exposed two-year-old zebrafish to waterborne lead acetate (1, 10, 100, 1000, or 10,000 µg/L) or a vehicle (DMSO) for 5 days. While lower concentrations (1–100 µg/L) reflect environmentally relevant Pb levels, higher concentrations (1000–10,000 µg/L) were included to assess acute toxicity under extreme exposure scenarios. We conducted adult behavior assessment to evaluate the locomotor activity following exposure. The same individual fish were subsequently sacrificed for brain dissection after a day of recovery in the aquatic system. RNA extraction and sequencing were then performed to evaluate the Pb-induced transcriptomic changes. Higher (1000–10,000 ug/L) Pb levels induced hyperactive locomotor patterns in aged zebrafish, while lower (10–100 ug/L) Pb levels resulted in the lowest locomotor activity compared to the control group. Exposure to 100 µg/L led to the highest number of differentially expressed genes (DEGs), while 10,000 µg/L induced larger fold changes in both directions. The neurological pathways impacted by Pb exposure include functions related to neurotransmission, such as cytoskeletal regulation and synaptogenesis, and oxidative stress response, such as mitochondrial dysfunction and downregulation of heat shock protein genes. These findings emphasize a U-shape dose–response relationship with Pb concentrations in locomotor activity and transcriptomic changes in the aging brain. [ABSTRACT FROM AUTHOR]

The impact of fertilization and irrigation on heavy metal accumulation in saline–alkali soil and its underlying mechanisms are critical issues given the constraints that soil salinization places on agricultural development and crop quality. This study addressed these issues by investigating the effects of adjusting organic fertilizer types, proportions, and irrigation volumes on the physicochemical properties of lightly to moderately saline–alkali soils and analyzing the interaction mechanisms between microorganisms and heavy metals. The results indicate that the rational application of organic fertilizers combined with supplemental irrigation can mitigate soil salinity accumulation and water deficits, and reduce the soil pH, thereby enhancing soil oxidation, promoting nitrogen transformation and increasing nitrate–nitrogen levels. As the proportion of organic fertilizers increased, heavy metal residues, enrichment, and risk indices in the crop grains also increased. Compared to no irrigation, supplemental irrigation of 22 mm during the grain-filling stage increased soil surface Cd content, Zn content, and the potential ecological risk index (HRI) by 10.2%, 3.1%, and 8%, respectively, while simultaneously reducing the heavy metal content in grains by 12–13.5% and decreasing heavy metal enrichment. Principal component analysis revealed the primary factors influencing Cu and Zn residues and Cd accumulation in the crop grains. Soil salinity was significantly negatively correlated with soil pH, organic matter, total nitrogen, and ammonium nitrogen, whereas soil organic matter, total nitrogen, ammonium nitrogen, soil pH, oxidation–reduction potential, soluble nitrogen, and microbial biomass nitrogen were positively correlated. The accumulation and residues of Zn and Cu in the soil were more closely correlated with the soil properties compared to those of Cd. Specifically, Zn accumulation on the soil surface was primarily related to aliphatic organic functional groups, followed by soil salinity. Residual Zn in the crop grains was primarily associated with soil oxidation–reduction properties, followed by soil moisture content. The accumulation of Cu on the soil surface was mainly correlated with the microbial biomass carbon (MBC), whereas the residual Cu in the crop grains was primarily linked to the soil moisture content. These findings provide theoretical insights for improving saline–alkali soils and managing heavy metal contamination, with implications for sustainable agriculture and environmental protection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A critical review and analysis of the literature relevant to the phenolic content of eucaryotic microalgae was performed. Several issues were identified and discussed. In summary, the main problems with the reporting on the phenolic content of microalgae are the following: (1) despite its usefulness in the determination of phenolic content in plant samples, the Folin–Ciocalteu assay is non-suitable for microalgal research due to the high presence of interfering compounds in microalgal extracts such as chlorophyll and its derivatives in organic extracts and free aromatic amino acids or nucleotides in aqueous extracts; (2) while there is chromatographic evidence for the presence of simple phenolic acids in most microalgal clades, the lack of critical enzymes of phenolic biosynthesis in most microalgae, as well as the high variability of phenolic profiles even in the same genus, require more extensive research before conclusions are drawn; (3) the accumulation and metabolism of external phenolics by microalgae has been almost universally neglected in studies focusing on the phenolic content of microalgae, even when natural seawater or complex organic media are used in the cultivation process. Despite these issues, the literature focusing on the bioremediation of waste streams rich in phenolics through microalgae demonstrates the ability of those organisms to adsorb, internalize, and in many cases oxidize or transform a wide range of phenolic compounds, even at very high concentrations. Simple phenolics found in waste streams, such as olive mill waste, have been shown to enhance the antioxidant activity and various bioactivities of microalgal extracts, while complex biotransformation products of phenolics have also been characterized. In conclusion, the de novo biosynthesis of phenolic compounds via eucaryotic microalgae requires further investigation with better designed experiments and suitable analytical methods, while the response of microalgae to phenolic compounds in their growth medium is of great practical interest, both in terms of waste treatment and for the production of functional foods, cosmetics, and pharmaceuticals. [ABSTRACT FROM AUTHOR]

Coal gangue hill, a significant anthropogenic interference, can cause various forms of land degradation. The promoting effect of coal gangue on soil qualities has also been discovered. However, few studies investigated the soil properties and microbiome of prolonged gangue hills. Here, we investigated soil microbial communities and chemical properties in a vegetated gangue hill and adjacent cropland and wasteland (regarded as gangue‐free lands). We did not find any significant differences in the content of organic matter, total nitrogen, and total phosphorus between the gangue hill and the cropland (Kruskal–Wallis test, p > 0.05). The content of all metals we investigated (Pb, Ni, Sb, Fe, and Al) did not exceed the risk control values (GB 15618‐2018; GB 36600‐2018). The content of Fe and soil electrical conductivity of the gangue hill was significantly higher than the gangue‐free lands (about 2 times and 20 times, respectively), which were also the key factors shaping microbial communities (Mantel's test, p < 0.05). There were no significant differences in the composition of the bacterial communities between the gangue hill and gangue‐free lands. The random‐forest model identified four species belonging to Actinobacteria and Ascomycota as the unique species in the gangue hill. Functional annotation revealed that the significant differences between the two land types were in bacterial nutrition types, fungal saprophytic types, and nitrogen cycling. Our study provided a theoretical foundation for land management and sustainable utilization in abandoned mining areas. [ABSTRACT FROM AUTHOR]

An investigation was undertaken to assess the potential for heavy metal leaching from gold tailings (GTs) when used GTs as fine aggregate for concrete. The leaching behavior in different pH leaching solutions and long-term leaching features of gold tailings concrete were studied. A kinetic model was used to predict the total amount of heavy metal leaching that will occur in next thirty years. The results reveal that the levels of Ba, Cd, Cr, Pb, Mn and Cu in GTs exceed the natural levels of these elements found in Chinese soil. Significantly, the leaching of Ba, Cd, Pb, Mn and Cu is more evident. GTs content shows a positive correlation with the leaching amount of heavy metals, and the cumulative leaching amount of heavy metals drops dramatically after 16 d. Based on 30 years leaching amount prediction, the leaching amount of Pb, Cu and Ba is 2 - 3 mg / L, while the leaching amount of Cd, Cr and Mn is less than 1 mg / L. These findings indicate that the GTs is sufficiently cured in concrete, thereby reducing the risk of long-term leaching of heavy metals. [ABSTRACT FROM AUTHOR]

Effects of heavy metals on soil microbial communities have been extensively studied due to their persistence in the environment and imposed threats to living organisms; however, there is a lack of in-depth studies of the impacts of heavy metals on plant endophyte communities. Therefore, the responses of plant endophyte communities to different concentrations of heavy metals were investigated in this study. The endophyte communities of plants existing in severely (W1, Pb, 110.49 mg/kg, Cd, 1.11 mg/kg), moderately (W2, Pb, 55.06 mg/kg, Cd, 0.48 mg/kg), and mildly (W3, Pb, 39.06 mg/kg, Cd, 0.20 mg/kg) contaminated soils were analyzed by 16s rRNA high-throughput Illumina sequencing. Furthermore, networks were constructed to illustrate the relationships between microorganisms and environmental factors. High-quality sequences were clustered at a 97% similarity level. Results revealed that the diversity of the community and relative abundance of Cyanobacteria phylum increased with decreasing levels of pollution. Cyanobacteria and Proteobacteria were found to be the dominant phylum, while Methylobacterium and Sphingomonas were observed as the dominant genus. Tukey's HSD test showed that the relative abundances of Cyanobacteria and Proteobacteria phyla and Methylobacterium and Sphingomonas genera differed significantly (p < 0.01) among the plants of the three sample sites. Environmental factor analysis revealed a significant negative correlation (p < 0.01) of Cyanobacteria and a significant positive correlation (p < 0.01) of Methylobacterium with the heavy metal content in the environment. These findings suggest that Cyanobacteria and Methylobacterium may be phylum and genus indicators, respectively, of heavy metal toxicity. Tax4Fun analysis showed the effect of heavy metal toxicity on the abundance of genes involved in plant metabolism. In addition, culturable endophytic strains were isolated to study their resistance to heavy metal stress and their ability to promote plant growth. The potting tests showed that the JG1 strain was tolerant to heavy metals, and it could significantly promote the growth of the host plant under stress caused by multiple heavy metals. Compared to the control, the JG1-treated plants showed a 23.14% increase in height and a 12.84% increase in biomass. Moreover, AP, AK, and HN contents in JG1-treated plants were 20.87%, 12.55%, and 9.03% higher, respectively, under heavy metal stress. The results of this study provide a scientific basis for the construction of an efficient plant endophyte restoration system. [ABSTRACT FROM AUTHOR]

Breast milk is the natural source of nutrition for infants, but while it supports their health, it can also be a potential source of toxic inorganic particulate matter, and this applies to both breast milk and industrially produced milk. The aim of the present study was to evaluate the presence of nanoparticles in both breast milk and formula milk samples. We collected and analyzed, via a new electron scanning microscopic procedure, 19 samples of breast milk from Italian women and 19 formula milk samples produced by different companies. Organic–inorganic agglomerates were detected in 58% of formula and in 63% of breast milk samples, respectively. In addition, a significantly (p < 0.05) greater size of nanoparticles was observed in formula milk samples. The results, showing the presence of inorganic nanosized particles in breast and artificial milk, may lead to future studies aimed at investigating possible nanosized contamination of milk and identifying early prevention strategies for women and animals involved in the food chain. [ABSTRACT FROM AUTHOR]

Hexachlorobenzene (HCB) is one of the most persistent environmental pollutants of global concern. Ni/Fe nanoparticles, with their small particle size, large surface area, and high reactivity, are a promising candidate for HCB degradation. In this work, we investigated the kinetics and products of the dechlorination of HCB by Ni/Fe nanoparticles and how the presence of heavy metal ions Cd(Ⅱ) and Zn(Ⅱ) influences the reaction. It is found that 400 μg/L HCB can be rapidly removed by 7.5 g/L Ni/Fe nanoparticles and the removal percentage reaches 99% in 48 h. The removal is facilitated by adsorption and sequential dechlorination of HCB, producing PCB, 1,2,3,4-TeCB, and 1,2,3-TCB as the main products, with 1,2,3,5/1,2,4,5-TeCB, 1,2,4-TCB, and 1,2-DCB as the minor products. The addition of heavy metal ions Cd(Ⅱ) and Zn(Ⅱ) does not significantly affect the removal rate of HCB but hinders the adsorption and degradation of the byproducts through competitive adsorption. Additionally, the concentration of both Cd(Ⅱ) and Zn(Ⅱ) decreases rapidly and achieves over 98% removal in 4 h. Our study reveals that Ni/Fe nanoparticles can remove HCB and heavy metals Cd(Ⅱ) and Zn(Ⅱ) concurrently, with the extent of HCB dechlorination reduced compared to that without heavy metal. These findings may inform the application of Ni/Fe nanoparticles in the treatment of water bodies and soil contaminated by both halogenated aromatics and heavy metal. [ABSTRACT FROM AUTHOR]

Introduction: Transcriptomics studies speed up the basic and applied research on the identification of genes involved in the biosynthesis of medicinally significant primary and secondary metabolites as well as plant responses to biotic and abiotic stresses. The adequate quality and quantity of RNA are essential for successful transcriptomics investigations such as RNA sequencing (RNA-seq) and microarrays. It is extremely difficult to isolate RNA from medicinal plants with high levels of polyphenols and polysaccharides, such as Borago officinalis. Moreover, isolating nucleic acids from tissues exposed to stressful conditions of heavy metal toxicity such as cadmium is challenging due to the increased accumulation of reactive oxygen species (ROS) and secondary metabolites. Any RNA-seq experiment requires high-quality RNA because the isolated RNA should meet stringent quality control requirements in order to be sequenced on the various platforms. In the present study, we evaluated different RNA extraction methods to obtain an efficient protocol for isolating high-quality total RNA from borage tissue exposed to cadmium stress. Materials and methods: The borage seedlings were grown in hydroponic containers containing half-strength Hoagland's nutrient solution in a growth chamber. Borage seedlings were exposed to 162 μM Cd using cadmium nitrate (Cd (NO3)2.4H2O) at 5-6 leaves stage and sampled at 48 h after treatment. The roots and leaves were subjected to five RNA isolation methods, including phenol/chloroform-based method, CTAB-based method, SDS-based method, RNX-plus protocol, and modified RNX-plus method to obtain an efficient protocol for isolating high-quality total RNA. The concentration and purity of the RNAs extracted using the abovementioned protocols were determined using gel electrophoresis and NanoDrop spectrophotometer. The quality and integrity of selected total RNA were approved with cDNA synthesis, RT-PCR, Bioanalyzer System, and transcriptome sequencing. After evaluating the extraction methods, a quick, simple and efficient instruction based on the modified RNX-Plus extraction method was afforded. Results and discussion: The results showed that the modified RNX-plus method was a fast and efficient protocol for the isolation of RNA from the borage leaf and root when compared with other methods. The method overcame the limitations posed by poor quality and low concentration of isolated RNA from borage samples exposed to cadmium stress. The A260/A280 and A260/A230 ratios of the RNA extracted using the modified RNX-plus method were 2.1 and 2.07, respectively, revealing its high purity. The key factors in the optimized protocol that resulted in removing the impurities were included the increasing ratio of extraction buffer to the amount of the powdered plant sample, using the optimized volume of chloroform, raising the RNA precipitation time at -20°C, washing RNA with lithium chloride and washing again with ethanol. Also, the yields of 333±15 and 463±43 ng μl-1 of RNA with RNA integrity (RIN) numbers of 8.6 and 9.05 were obtained from roots under cadmium stress and control conditions using the described optimized method, respectively. Conclusion: In general, the results of this study showed that the modified RNX-Plus method is convenient, fast, and effective for the isolation of total RNA from borage root and leaf tissues that contain different levels of polysaccharides, polyphenols, and secondary metabolites, and no solution is needed to be prepared before, except for ethanol and Lithium chloride. Since the RNA extracted from this procedure was successfully used for cDNA library construction, RT-PCR, and RNA sequencing, it can be considered as a simple and efficient method for the isolation of RNA from medicinal plants. [ABSTRACT FROM AUTHOR]