Green synthesis of magnetite iron oxide nanoparticles using Azadirachta indica leaf extract loaded on reduced graphene oxide and degradation of methylene blue.

In the current arena, new-generation functional nanomaterials are the key players for smart solutions and applications including environmental decontamination of pollutants. Among the plethora of new-generation nanomaterials, graphene-based nanomaterials and nanocomposites are in the driving seat surpassing their counterparts due to their unique physicochemical characteristics and superior surface chemistry. The purpose of the present research was to synthesize and characterize magnetite iron oxide/reduced graphene oxide nanocomposites (FeNPs/rGO) via a green approach and test its application in the degradation of methylene blue. The modified Hummer's protocol was adopted to synthesize graphene oxide (GO) through a chemical exfoliation approach using a graphitic route. Leaf extract of Azadirachta indica was used as a green reducing agent to reduce GO into reduced graphene oxide (rGO). Then, using the green deposition approach and Azadirachta indica leaf extract, a nanocomposite comprising magnetite iron oxides and reduced graphene oxide i.e., FeNPs/rGO was synthesized. During the synthesis of functionalized FeNPs/rGO, Azadirachta indica leaf extract acted as a reducing, capping, and stabilizing agent. The final synthesized materials were characterized and analyzed using an array of techniques such as scanning electron microscopy (SEM)-energy dispersive X-ray microanalysis (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis, and UV-visible spectrophotometry. The UV-visible spectrum was used to evaluate the optical characteristics and band gap. Using the FT-IR spectrum, functional groupings were identified in the synthesized graphene-based nanomaterials and nanocomposites. The morphology and elemental analysis of nanomaterials and nanocomposites synthesized via the green deposition process were investigated using SEM-EDX. The GO, rGO, FeNPs, and FeNPs/rGO showed maximum absorption at 232, 265, 395, and 405 nm, respectively. FTIR spectrum showed different functional groups (OH, COOH, C=O), C-O-C) modifying material surfaces. Based on Debye Sherrer's equation, the mean calculated particle size of all synthesized materials was < 100 nm (GO = 60-80, rGO = 90-95, FeNPs = 70-90, Fe/GO = 40-60, and Fe/rGO = 80-85 nm). Graphene-based nanomaterials displayed rough surfaces with clustered and spherical shapes and EDX analysis confirmed the presence of both iron and oxygen in all the nanocomposites. The final nanocomposites produced via the synthetic process degraded approximately 74% of methylene blue. Based on the results, it is plausible to conclude that synthesized FeNPs/rGO nanocomposites can also be used as a potential photocatalyst degrader for other different dye pollutants due to their lower band gap.

Phosphate solubilizing Aspergillus Niger PH1 ameliorates growth and alleviates lead stress in maize through improved photosynthetic and antioxidant response.

Among the several threats to humanity by anthropogenic activities, contamination of the environment by heavy metals is of great concern. Upon entry into the food chain, these metals cause serious hazards to plants and other organisms including humans. Use of microbes for bioremediation of the soil and stress mitigation in plants are among the preferred strategies to provide an efficient, cost-effective, eco-friendly solution of the problem. The current investigation is an attempt in this direction where fungal strain PH1 was isolated from the rhizosphere of Parthenium hysterophorus which was identified as Aspergillus niger by sequence homology of the ITS 1 and ITS 4 regions of the rRNA. The strain was tested for its effect on growth and biochemical parameters as reflection of its potential to mitigate Pb stress in Zea mays exposed to 100, 200 and 500 µg of Pb/g of soil. In the initial screening, it was revealed that the strain has the ability to tolerate lead stress, solubilize insoluble phosphate and produce plant growth promoting hormones (IAA and SA) and other metabolites like phenolics, flavonoids, sugar, protein and lipids. Under 500 µg of Pb/g of soil, Z. mays exhibited significant growth retardation with a reduction of 31% in root length, 30.5% in shoot length, 57.5% in fresh weight and 45.2% in dry weight as compared to control plants. Inoculation of A. niger to Pb treated plants not only restored root and shoot length, rather promoted it to a level significantly higher than the control plants. Association of the strain modulated the physio-hormonal attributes of maize plants that resulted in their better growth which indicated a state of low stress. Additionally, the strain boosted the antioxidant defence system of the maize there by causing a significant reduction in the ascorbic acid peroxidase (1.5%), catalase (19%) and 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical scavenging activity (33.3%), indicating a lower stress condition as compared to their non-inoculated stressed plants. Based on current evidence, this strain can potentially be used as a biofertilizer for Pb-contaminated sites where it will improve overall plant health with the hope of achieving better biological and agricultural yields.

Hospitalisations Due to Dental Infection: A Retrospective Clinical Audit from an Australian Public Hospital.

The aim of this clinical audit is to evaluate the characteristics of dental infections requiring hospitalisations, which may help improve preventative and management policies. This study retrospectively evaluated the records of patients admitted to the Nepean hospital, Kingswood, New South Wales, Australia, due to dental infections between 2018 and 2019. A total of 102 patients, mostly in their thirties with equal gender distribution, were admitted with dental infections, presenting with pain (100%), swelling (99%), trismus (40.2%), dysphagia (27.4%), fever (21%) [>37 °C], tachycardia (24.8%) and tachypnoea (9.3%). Most patients (68%) presented on weekends, outside regular working hours, and public holidays. A total of 52.5% of patients had taken prior antibiotics. Dental caries, smoking, mental health issues, and illicit drug use were featured strongly. The majority of patients (56.4%) underwent treatment under local anaesthesia. The total length of hospital stay was 271 days (mean 2.7, SD 1.6). Augmentin was the most prescribed antibiotic. Complications were reported in 8.8% of the patients, primarily due to airway compromise. Dental infections leading to hospitalisations continue to be a burden on the healthcare system. A notable finding was that the presentations were primarily on weekends, outside regular working hours, and public holidays, and the majority required dental interventions under local anaesthesia. The provision of on-call emergency dental services may reduce potentially preventable hospitalisations and the length of hospital stay.

Effect of green-synthesized copper oxide nanoparticles on growth, physiology, nutrient uptake, and cadmium accumulation in Triticum aestivum (L.).

Cadmium (Cd) stress in crops has been serious concern while little is known about the copper oxide nanoparticles (CuO NPs) effects on Cd accumulation by crops. This study investigated the effectiveness of CuO NPs in mitigating Cd contamination in wheat (Triticum aestivum L.) cultivation through a pot experiment, presenting an eco-friendly solution to a critical agricultural concern. The CuO NPs, synthesized using green methods, exhibited a circular shape with a crystalline structure and a particle size ranging from 8 to 12 nm. The foliar spray of CuO NPs was applied in four different concentrations i.e. control, 25, 50, 75, 100 mg/L. The obtained data demonstrated that, in comparison to the control group, CuO NPs had a beneficial influence on various growth metrics and straw and grain yields of T. aestivum. The green CuO NPs improved T. aestivum growth and physiology under Cd stress, enhanced selected enzyme activities, reduced oxidative stress, and decreased malondialdehyde levels in the T. aestivum plants. CuO NPs lowered Cd contents in T. aestivum tissues and boosted the uptake of essential nutrients from the soil. Overall, foliar applied CuO NPs were effective in minimizing Cd contents in grains thereby reducing the health risks associated with Cd excess in humans. However, more in depth studies with several plant species and application methods of CuO NPs are required for better utilization of NPs in agricultural purposes.

Multi-Walled CNTs/BiVO4 Heterostructures for Solar-Driven Evaporation System and Efficient Photocatalytic Activity against Oxytetracycline.

Developing a sustainable environment requires addressing primitive water scarcity and water contamination. Antibiotics such as oxytetracycline (OTC) may accumulate in the environment and in the human body, increasing the risks to the ecosystem. The treatment of polluted water and the production of potable water can be achieved in a variety of ways, including photodegradation, solar distillation, and filtration. Freshwater supplies can be increased by implementing energy-efficient technologies for the production of clean water. Solar water evaporation combined with photocatalytic degradation and sterilization offers a promising avenue for integration into the clean water and energy production fields. The present study reports the synthesis of a 3D solar steam generator comprised of BiVO4 and carbon nanotubes (CNT) nanocomposite decorated over a cigarette filter as the light-to-heat conversion layer for solar steam generation. The BiVO4@CNT-based 3D solar evaporator over the hydrophilic cellulosic fibers of the cigarette filter endowed excellent evaporation rates (2.36 kg m-2 h-1) under 1 kW m-2 solar irradiation, owing to its superior hydrophilicity and broadband solar absorption (96%) equipped with localized heating at microscale thermal confinement optimized by the minimum thermal conductivity of the overall system. Furthermore, the BiVO4@CNT composite exhibited a heightened photo activity up to 83% of the photodegradation of oxytetracycline (OTC) antibiotic due to the inhibition of charge recombination from the industrial effluents. This approach transforms the water-energy nexus into a synergistic bond that offers opportunities to meet expected demand, rather than being competitive.

Green synthesis and characterization of silver and copper nanoparticles and their use as an effective adsorbent for chromium removal and recovery from wastewater.

Chromium (Cr) is one of the hazardous heavy metals that is naturally carcinogenic and causes various health problems. Metallic nanoparticles such as silver and copper nanoparticles (Ag NPs and Cu NPs) have gained great attention because of their unique chemical, physical, and biological attributes, serving diverse and significant role in various useful and sustainable applications. In the present study, both of these NPs were synthesized by green method in which Azadirachta indica plant extract was used. These nanoparticles were characterized by using advanced instrumental techniques such as Fourier transmission infrared (FTIR), X-ray diffraction (XRD), scanning electron microscope attached with energy-dispersive spectroscopy (SEM-EDS), and elemental mapping. These environmentally friendly nanoparticles were utilized for the batch removal of Cr from the wastewater. For analysis of adsorption behaviour, a range of kinetic isotherm models (Freundlich, Temkin, Dubinin, and Langmuir) and kinetic models (pseudo-first-order and pseudo-second-order) were used for the Cu-NPs and Ag-NPs. Cu NPs exhibited the highest Cr removal efficiency (96%) within a contact time of 10-15 min, closely followed by Ag NPs which achieved a removal efficiency of 94% under the similar conditions. These optimal outcomes were observed at a sorbent dose of 0.5 g/L for Ag NPs and 0.7 g/L for Cu NPs. After effectively capturing Cr using these nanoparticles, the sorbates were examined through SEM-EDX analysis to observe how much Cr metal was attached to the nanoparticles, potentially for future use. The analysis found that Ag-NPs captured 18% of Cr, while Cu-NPs captured 12% from the aqueous solution. More precise experimental conditions are needed for higher Cr removal from wastewater and determination of the best conditions for industrial-level Cr reuse. Although nanomaterial exhibit high efficiency and selectivity for Cr removal and recovery from wastewater, more research is necessary to optimize their synthesis and performance for industrial-scale applications and develop efficient methods for Cr removal and recovery.

Evaluation of nanoceria on cadmium uptake in Triticum aestivum (L.) and its implications for dietary health risk.

In recent times, significant attention has been directed toward the synthesis and application of nanoparticles (NPs) in agriculture sector. In current study, nanoceria (CeO2 NPs) synthesized by green method were employed to address cadmium (Cd) accumulation in wheat (Triticum aestivum L.) cultivated in field with excess Cd. The application of CeO2 NPs was carried out through foliar spraying, performed twice during the growth of T. aestivum. Four levels of CeO2 NPs were used: T0, T1, T2, and T3 as 0, 50, 75, and 100 mgL-1, respectively. Results highlighted the positive effects of CeO2 NPs on various growth parameters, including plant height, spike length, photosynthetic related attributes, as well as straw and grain of grains in comparison to T1 (control group). Furthermore, CeO2 NPs led to a reduction in oxidative stress in the leaves and enhanced in enzyme activities in comparison to T1. Notably, Cd concentrations in straw, roots, and grains exhibited a decline following the treatment with CeO2 NPs, in contrast to the control group. In terms of health implications, the calculated health risk index associated with dietary consumption of grains by adults remained below the defined threshold with supply of nanoparticles. Foliar application of CeO2 NPs proved to be an effective approach in reducing cadmium content in wheat grains. This reduction holds significant potential for minimizing the risk of cadmium exposure to human health through the food chain. Employing the green synthesis method amplifies the potential for extensive production and a wide array of environmental applications for CeO2 NPs. This dual capacity makes them proficient in tackling environmental stresses while concurrently mitigating adverse ecological effects.

Iron-modified biochar improves plant physiology, soil nutritional status and mitigates Pb and Cd-hazard in wheat (Triticum aestivum L.).

Environmental quality and food safety is threatened by contamination of lead (Pb) and cadmium (Cd) heavy metals in agricultural soils. Therefore, it is necessary to develop effective techniques for remediation of such soils. In this study, we prepared iron-modified biochar (Fe-BC) which combines the unique characteristics of pristine biochar (BC) and iron. The current study investigated the effect of pristine and iron modified biochar (Fe-BC) on the nutritional values of soil and on the reduction of Pb and Cd toxicity in wheat plants (Triticum aestivum L.). The findings of present study exhibited that 2% Fe-BC treatments significantly increased the dry weights of roots, shoots, husk and grains by 148.2, 53.2, 64.2 and 148%, respectively compared to control plants. The 2% Fe-BC treatment also enhanced photosynthesis rate, transpiration rate, stomatal conductance, intercellular CO2, chlorophyll a and b contents, by 43.2, 88.4, 24.9, 32.5, 21.4, and 26.7%, respectively. Moreover, 2% Fe-BC treatment suppressed the oxidative stress in wheat plants by increasing superoxide dismutase (SOD) and catalase (CAT) by 62.4 and 69.2%, respectively. The results showed that 2% Fe-BC treatment significantly lowered Cd levels in wheat roots, shoots, husk, and grains by 23.7, 44.5, 33.2, and 76.3%. Whereas, Pb concentrations in wheat roots, shoots, husk, and grains decreased by 46.4, 49.4, 53.6, and 68.3%, respectively. Post-harvest soil analysis showed that soil treatment with 2% Fe-BC increased soil urease, CAT and acid phosphatase enzyme activities by 48.4, 74.4 and 117.3%, respectively. Similarly, 2% Fe-BC treatment significantly improved nutrients availability in the soil as the available N, P, K, and Fe contents increased by 22, 25, 7.3, and 13.3%, respectively. Fe-BC is a viable solution for the remediation of hazardous Cd and Pb contaminated soils, and improvement of soil fertility status.

Risk assessment of toxic and hazardous metals in paddy agroecosystem by biochar-for bio-membrane applications.

Toxic and carcinogenic metal (loid)s, such arsenic (As) and cadmium (Cd), found in contaminated paddy soils pose a serious danger to environmental sustainability. Their geochemical activities are complex, making it difficult to manage their contamination. Rice grown in Cd and As-polluted soils ends up in people's bellies, where it can cause cancer, anemia, and the deadly itai sickness. Solving this issue calls for research into eco-friendly and cost-effective remediation technology to lower rice's As and Cd levels. This research delves deeply into the origins of As and Cd in paddy soils, as well as their mobility, bioavailability, and uptake mechanisms by rice plants. It also examines the current methods and reactors used to lower As and Cd contamination in rice. Iron-modified biochar (Fe-BC) is a promising technology for reducing As and Cd toxicity in rice, improving soil health, and boosting rice's nutritional value. Biochar's physiochemical characteristics are enhanced by the addition of iron, making it a potent adsorbent for As and Cd ions. In conclusion, Fe-BC's biomembrane properties make them an attractive option for remediating As- and Cd-contaminated paddy soils. More efficient mitigation measures, including the use of biomembrane technology, can be developed when sustainable agriculture practices are combined with these technologies.

Water Quality Index and Human Health Risk Assessment of Drinking Water in Selected Urban Areas of a Mega City.

The present study was conducted to evaluate the quality of drinking water and assess the potential health hazards due to water contaminants in selected urban areas of Lahore, Pakistan. Water samples were collected from ten sites and analyzed for different physico-chemical parameters including turbidity, color, pH, total dissolved solids (TDS), nitrates, fluoride, residual chlorine, and total hardness. Additionally, heavy metal (arsenic) and microbial parameters (E. coli) were also determined in the water samples. Drinking water quality evaluation indices, including the water quality index (WQI) for physico-chemical and biological parameters and human health risk assessment (HHRA) for heavy metal were estimated using the analytical results of the target parameters. It was found in most of the areas that the levels of arsenic, fluoride, TDS, and residual chlorine were higher than those recommended by the National Environmental Quality Standard (NEQS) and World Health Organization (WHO) guidelines. In addition to the physico-chemical parameters, microbial content (E. coli) was also found in the drinking water samples of the selected areas. Statistical analysis of the results indicated that levels of target parameters in drinking water samples are significantly different between sampling sites. The WQI for all physico-chemical and microbial parameters indicated that drinking water in most of the areas was unfit and unsuitable (WQI > 100) for drinking purposes except for the water of Bhatti Gate and Chota Gaon Shahdara with a WQI of 87 and 91, respectively. Drinking water in these areas had a very poor WQI rating. According to HHRA, drinking water from the selected sites was found to be of high risk to children and adults. The carcinogenic risk of arsenic indicated that all samples were of high risk to both adults and children (4.60 and 4.37 × 10-3, respectively). Regular monitoring of drinking water quality is essential, and proactive measures must be implemented to ensure the treatment and availability of safe drinking water in urban areas.

Enhancing chromium removal and recovery from industrial wastewater using sustainable and efficient nanomaterial: A review.

Water contamination can be detrimental to the human health due to higher concentration of carcinogenic heavy metals such as chromium (Cr) in the wastewater. Many traditional methods are being employed in wastewater treatment plants for Cr removal to control the environmental impacts. Such methods include ion exchange, coagulation, membrane filtration, and chemical precipitation and microbial degradation. Recent advances in materials science and green chemistry have led to the development of nanomaterial that possess high specific surface areas and multiple functions, making them suitable for removing metals such as Cr from wastewater. Literature shows that the most efficient, effective, clean, and long-lasting approach for removing heavy metals from wastewater involves adsorbing heavy metals onto the surface of nanomaterial. This review assesses the removal methods of Cr from wastewater, advantages and disadvantages of using nanomaterial to remove Cr from wastewater and potential negative impacts on human health. The latest trends and developments in Cr removal strategies using nanomaterial adsorption are also explored in the present review.

Rapid Method for Quantification of Iron (Fe+3) from Ferrazone (NaFe-EDTA) in Fortified Wheat Flour.

Conventional methods for quantifying the added iron in wheat flour are time-consuming and costly. A rapid method (Time/Sample: 95 min) was developed by modifying the conventional standard method (Time/Sample: 560 min) and validated. Linearity and linear regression of the rapid method presented excellent correlation coefficient (R2) values (0.9976 to 0.9991), which were close to 1, while the limits of agreement (LOA) were in the range of -0.01 to 0.06 mg/kg. The limits of detection (LOD)/specificity and limits of quantitation (LOQ)/sensitivity values were found to be 0.03 and 0.09 mg/kg, respectively. The rapid method was subjected to validation, wherein the precision of intra-assay, inter-assay, and inter-person was determined to be within the range of 1.35-7.25%. These results indicate a high level of accuracy and precision of the method. The percent relative standard deviation (RSD) for recoveries at varying spiking levels, that is, 5, 10, and 15 mg/kg, was determined at 1.33 lying far below the upper limit of acceptability (RSD < 20). Overall, the developed rapid method can be sustainably alternate for conventional methods owing to its ability to produce accurate, precise, robust, and reproducible results.

Recent Progress and Perspective of an Evolving Carbon Family From 0D to 3D: Synthesis, Biomedical Applications, and Potential Challenges.

A variety of imaging techniques are available for detecting biological processes with sufficient penetration depth and temporal resolution. However, inflammation, cardiovascular, and cancer-related disorders might be difficult to diagnose with typical bioimaging methods because of the lack of resolution in the imaging of deep tissues. Therefore, nanomaterials are the most promising candidate to overcome this hurdle. This review is on the utilization of carbon-based nanomaterials (CNMs), ranging from zero-dimension (0D) to three-dimension (3D), in the development of fluorescence (FL) imaging, photoacoustic imaging (PAI), and biosensing for the early detection of cancer. Nanoengineered CNMs, such as graphene, carbon nanotubes (CNTs), and functional carbon quantum dots (QDs), are being further studied for multimodal biometrics and targeted therapy. CNMs have many advantages over conventional dyes in FL sensing and imaging, including clear emission spectra, long photostability, low cost, and high FL intensity. Nanoprobe production, mechanical illustrations, and diagnostic therapeutic applications are the key areas of focus. The bioimaging technique has facilitated a greater understanding of the biochemical events underlying multiple disease etiologies, consequently facilitating disease diagnosis, evaluation of therapeutic efficacy, and drug development. This review may lead to the development of interdisciplinary research in bioimaging and sensing as well as possible future concerns for researchers and medical physicians.

Effect of titanium dioxide nanoparticles and co-composted biochar on growth and Cd uptake by wheat plants: A field study.

Cadmium (Cd) is a common toxic trace element found in agricultural soils which is mainly due to anthropogenic activities. Cadmium posed a significant risk to humans all around the world due to its cancer-causing ability. The current study demonstrated the effects of soil-applied biochar (BC) and foliar-applied titanium dioxide nanoparticles (TiO2 NPs) (at a rate of 0.5% and 75 mg/L respectively) alone or in combination on growth and Cd accumulation in wheat plants under field experiment. Soil applied BC and foliar TiO2 NPs, as well as BC coupled with TiO2 NPs, reduced Cd contents in grains by 32%, 47%, and 79%, than control respectively. The usage of NPs and BC boosted the plant height as well as chlorophyll contents by lowering oxidative injury and changing selected antioxidant enzyme activities in leaves than control plants. The combined use of NPs and BC prevented excess Cd accumulation in grains over the critical level (0.2 mg/kg) for cereals. The health risk index (HRI) due to Cd was reduced by 79% by co-composted BC + TiO2 NPs treatment than control. Although, HRI was lower than one for all treatments but this may exceed the limit if grains obtained from such field consumed over long periods. In conclusion, TiO2 NPs and BC amendments can be implemented in fields across the globe where excess Cd is present in soils. Additional studies on the use of such approaches in more precise experimental settings are needed in order to address this environmental problem at larger scale.

Reduction in the cadmium (Cd) accumulation and toxicity in pearl millet (Pennisetum glaucum L.) by regulating physio-biochemical and antioxidant defense system via soil and foliar application of melatonin.

Cadmium (Cd) is among the toxic pollutants that harms the both animals and plants. The natural antioxidant, melatonin can improve Cd-stress tolerance but its potential role in reducing Cd stress and resilience mechanisms in pearl millet (Pennisetum glaucum L.) is remain unclear. The present study suggests that Cd causes severe oxidative damage by decreasing photosynthesis, and increasing reactive oxygen species (ROS), malondialdehyde content (MDA), and Cd content in different parts of pearl millet. However, exogenous melatonin (soil application and foliar treatment) mitigated the Cd toxicity and enhanced the growth, antioxidant defense system, and differentially regulated the expression of antioxidant-responsive genes i. e superoxide dismutase SOD-[Fe] 2, Fe-superoxide dismutase, Peroxiredoxin 2C, and L-ascorbate peroxidase-6. The results showed that foliar melatonin at F-200/50 significantly increased the plant height, chlorophyll a, b, a+b and carotenoids by 128%, 121%, 150%, 122%, and 69% over the Cd treatment, respectively. The soil and foliar melatonin at S-100/50 and F-100/50 reduced the ROS by 36%, and 44%, and MDA by 42% and 51% over the Cd treatment, respectively. Moreover, F200/50 significantly boosted the activities of antioxidant enzymes i. e SOD by 141%, CAT 298%, POD 117%, and APX 155% over the Cd treatment. Similarly, a significant reduction in Cd content in root, stem, and leaf was found on exposure to higher concentrations of exogenous melatonin. These findings suggest that exogenous melatonin may significantly and differentially improve the tolerance to Cd stress in crop plants. However, field applications, type of plant species, concentration of dose, and type of stress may vary with the degree of tolerance in crop plants.

Glutathione treatment suppresses the adverse effects of microplastics in rice.

Oryza sativa is grown worldwide and exhibit sensitivity to different stresses. Exponential increase in microplastics in agroecosystems is damaging and demand pragmatic strategies to protect growth and yield losses. We evaluated exogenous application of different doses of glutathione (GSH) for mediation of physiological traits of rice plants experiencing two different MPs i.e. PET and HDPE in root zone. All the rice seedlings exhibited MP-induced significant (P ≤ 0.001) growth inhibition compared to the control plants. GSH application (T3) significantly increased the shoot fresh weight (8.80%), root fresh weight (19.22%), shoot dry weight (13.705%), root dry weight (25.52%), plant height (5.75%) and 100-grain weight (9.36%), compared to control plants. GSH treated plants (T4) showed a recovery mechanism by managing the marginal rate of reduction of all photosynthetic and gas exchange attributes by showing 34.44, 20.98, 34.83, 42.16, 39.70, and 51.38% reduction for Chl-a, Chl-b, total cholophyll, photosynthetic rate (A), transpiration rate (E), and stomatal conductance (Gs), respectively, compared to control plants. Under 5 mg L-1 HDPE and PET, rice seedlings without GSH treatment responded in terms of increase in total soluble sugar, total free amino acid, glutathione, glutathione disulfide contents, while total soluble protein and ascorbic acid contents decreased significantly, compared with control plants. Corrleation matrix revealed positive relationship between GSH and improvement in studied attributes. Moreover, exogenous GSH improved rice growth and productivity to counter the negative role of MPs. This unique study examined the effects of GSH on rice plants growing in MP-contaminated media and revealed how exogenous GSH helps plants survive MP-stress.

An assessment of the efficacy of biochar and zero-valent iron nanoparticles in reducing lead toxicity in wheat (Triticum aestivum L.).

Soil heavy metal contamination is increasing rapidly due to increased anthropogenic activities. Lead (Pb) is a well-known human carcinogen causing toxic effects on humans and the environment. Its accumulation in food crops is a serious hazard to food security. Developing environment-friendly and cost-efficient techniques is necessary for Pb immobilization in the soil. A pot experiment was executed to determine the role of biochar (BC), zero-valent iron nanoparticles (n-ZVI), and zero-valent iron nanoparticles biochar composite (n-ZVI-BC) in controlling the Pb mobility and bioaccumulation in wheat (Triticum aestivum L.). The results showed that BC and n-ZVI significantly enhanced the wheat growth by increasing their photosynthetic and enzymatic activities. Among all the applied treatments, the maximum significant (p ≤ 0.05) improvement in wheat biomass was with the n-ZVI-BC application (T3). Compared to the control, the biomass of wheat roots, shoots & grains increased by 92.5, 58.8, and 49.1%, respectively. Moreover, the soil addition of T3 amendment minimized the Pb distribution in wheat roots, shoots, and grains by 33.8, 26.8, and 16.2%, respectively. The outcomes of this experiment showed that in comparison to control treatment plants, soil amendment with n-ZVI-BC (T3) increased the catalase (CAT), superoxide dismutase (SOD) activity by 49.8 and 31.1%, respectively, ultimately declining electrolyte leakage (EL), malondialdehyde (MDA) and hydrogen peroxide (H2O2) content in wheat by 38.7, 33.3, and 38%respectively. In addition, applied amendments declined the Pb mobility in the soil by increasing the residual Pb fractions. Soil amendment with n-ZVI-BC also increased the soil catalase (CAT), urease (UR), and acid phosphatase (ACP) activities by 68, 59, and 74%, respectively. Our research results provided valuable insight for the remediation of Pb toxicity in wheat. Hence, we can infer from our findings that n-ZVI-BC can be considered a propitious, environment friendly and affordable technique for mitigating Pb toxicity in wheat crop and reclamation of Pb polluted soils.

Enhancement of Cadmium Phytoremediation Potential of Helainthus annus L. with Application of EDTA and IAA.

The aim of the current study was to assess the cadmium (Cd) phytoremediation potential of Halianthus annus L. that was exposed to 50, 100, and 150 mg/kg of cadmium for 15, 30, and 60 days with application of EDTA (Ethylenediaminetetraacetic acid) in the soil and IAA (indole acetic acid) as a foliar spray. The results indicated that the concentration, duration of exposure, and amount of Cd affect the phytoremediation potential. The maximum Cd was observed at 60 days (32.05, 16.86, and 10.63%) of Cd application, compared to 15 (2.04, 0.60, and 1.17%) or 30 days (8.41, 3.93, and 4.20%, respectively), in a dose-dependent manner. The application of EDTA in the soil and foliar IAA enhanced the Cd accumulation in the plants at 15, 30, and 60 days of exposure, with maximum accumulation at 60 days. Exposed plants with foliar IAA application showed 64.82%, 33.77%, and 25.84% absorption at 50, 100, and 150 mg/kg, respectively. Apart from higher absorption, the cadmium translocation to the edible part of the plants ceased, i.e., the seeds had 0% accumulation. The interesting fact was recorded that efficient phytoremediation was recorded at 15 days of exposure, whereas maximum phytoremediation was recorded at 60 days of exposure. To minimize the stress, the host also produced stress-related metabolites (i.e., flavonoids, phenolics, proline, and sugar) and antioxidants (i.e., catalases and ascorbate peroxidases). From the current evidence, it could be assumed that the use of EDTA and IAA, along with hyperaccumulating plants, could be a possible green method to remediate Cd-contaminated soil efficiently in a short period of time.

Kinetic and isotherms modeling of methyl orange and chromium (VI) onto hexagonal ZnO microstructures as a membrane for environmental remediation of wastewater.

Globally, contamination of water by dyes and heavy metals (HMs) is a serious environmental and public health problem due to their carcinogenic and mutagenic nature. It is incumbent to treat innocuously before discharge. It is the first time, hexagonal zinc oxide (ZnO) microstructure are being employeed as a membrane in the simultaneous removal of methyl orange (MO) and chromium (Cr (VI)) from the aqueous solution. The surface chemistry of hexagonal ZnO was characterized for morphology, surface functional groups, crystalline nature, and elemental composition by scanning electron microscope (SEM), Fourier transmission infrared spectroscopy (FTIR), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). Adsorption capacity and removal efficiency was determined by the laboratory batch adsorption experiments, while nonlinear, linear kinetics and isotherm models were fitted to experimental data to investigate the adsorption process. The results exhibited that the maximum adsorption capacity (qmax) of hexagonal ZnO from the Langmuir isotherm model was 80.39 mg g-1 and 84.10 mg g-1 for MO and Cr (VI) respectively. According to the modeling findings, linear langmuir fitted to the experimental data with R2 0.967 and 0.971 for both MO and Cr (VI) which indicates monolayer physical adsorption of both pollutants has taken place. Whereas, kinetic study showed nonlinear pseudo-second order with R2 0.989 and 0.986 for MO and Cr (VI) model best fitted with the experimental data. The values of thermodynamics parameters Gibbs free energy change ΔG°, heat of enthalpy ΔH° and, heat of entropy ΔS° indicate that spontaneous, endothermic, and irreversible adsorption reactions occurred. Overall, it is concluded from our observations that hexagonal ZnO has the potential to be used as an eco-friendly, cost-effective adsorbent for simultaneous remaoval of both MO and Cr (VI) from water. Findings of the current investigation provide valuable insights for the development of an inexpensive, effective and sustainable filtration method for the treatment of MO and Cr (VI) synergistically.