International Journal of Phytoremediation最新文献

Tannery solid waste poses significant environmental challenges owing to its high metal content, especially Cr. Converting this waste into value-added byproduct i.e., biochar offers a sustainable management approach to reducing the waste load on landfill sites and also guarding the nearby fauna, flora and water bodies. This study aimed to develop metal-resistant microbial consortium loaded biochar (MCLB) by inoculating tannery solid waste biochar (BC) with consortium of ten Bacillus and/or five Trichoderma strains and their effect was evaluated on the morphological and biochemical attributes of sunflowers including metals immobilization. The soil amendment with BC at 2% rate improved the shoot height, dry biomass, and chlorophyll content in sunflowers but not in higher doses. However, the application of MCLB even at its highest concentration i.e., 10% dose showed a significant increase in shoot length (61.2%) and dry weight (656.9%) over BC only. The findings of metal bioavailability indicated that the application of MCLB having metal-resistant strains decreased the mobility of Cd, Cr, Cu, Ni, Pb and Zn into the sunflower tissues compared to BC. Moreover, MCLB enhanced the uptake of Fe and Mg which are beneficial to the plant. In addition to that, the results for phenolic and proline content demonstrated a considerable decrease by MCLB indicating less stress response as compared to BC. Therefore, these findings highlight the potential of MCLB as a sustainable soil amendment for improving the growth attributes of oil-yielding sunflower varieties by using tannery solid waste biochar while decreasing the uptake of nonessential metals. By pyrolyzing the tannery solid waste into biochar, this approach contributes to a circular economy and environmental remediation practices.

Remediation of heavy metal pollution is essential for safeguarding ecological integrity and public health. The present work aimed to prepare a novel biochar from Eucalyptus Camaldulensis leaves (EC-biochar) for the effective removal of Cd²⁺ and Pb²⁺ cations, as representative heavy metals, from aqueous solutions. The adsorption performance of Cd²⁺ and Pb²⁺ cations by EC-biochar was assessed by varying different operating parameters (e.g. pH, temperature, EC-biochar dose, adsorption time, and adsorbate concentration). The maximum removal efficiencies of Pb²⁺ (83.8%) and Cd²⁺ (89.6%) ions were achieved at pH 4.5. The pseudo-second order and Langmuir isotherm models satisfactorily predict the adsorption of Pb²⁺ and Cd²⁺ cations onto EC-biochar. The negative values of ΔG° and ΔH° demonstrated that the adsorption process is spontaneously feasible and exothermic. It is also worth pointing out that the regeneration/reuse study revealed that the as-prepared EC-biochar maintained an excellent adsorption performance after five reuse cycles, demonstrating its suitable reusability. These findings demonstrate that the EC-biochar can serve as an inexpensive, effective and recyclable adsorbent for treating heavy metal-laden effluents.

The discharge of wastewater containing toxic pollutants, such as lead [Pb(II)] and cadmium [Cd(II)], into water bodies is one of the most critical challenges nowadays. Apart from this, the daily generation of organic waste like vegetable, fruit, and flower waste in cities is increasing constantly. Therefore, a novel approach was adopted in this study that used flower waste (Tagetes erecta L. marigold) for the metal removal from polluted water with a view to manage flower waste and metal contaminants simultaneously. The characterization of prepared waste of T. erecta flowers and its biosorption capacity for Cd and Pb were investigated through various techniques viz., atomic absorption spectrophotometer (AAS), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), and Fourier transform infrared analysis (FTIR). Experiments for adsorption isotherm were carried out at the room temperature and the performance was determined using Langmuir and Freundlich adsorption models. Equilibrium data was confirmed to follow pseudo second order kinetics. The maximum adsorption capacities of flower waste for Cd(II) and Pb(II) were 52.6 and 21.74 mg g^-1, respectively. The study findings indicated that the optimum pH and time for the most effective elimination were pH 6 and 150 min, respectively, for Pb (80%) and Cd (91.8%).

This study investigates the potential of Citrus paradisi peel (CP) as biosorbent for the elimination of Rhodamine B (RhD B) from wastewater. The study used FTIR, SEM and EDX to determine the structure of CP. It was shown that 1.4 and 2.0 g were the optimal biosorbent doses for plain and treated peels, respectively. A number of factors were optimized in order to examine the sorbent efficiency for Rhodamine-B dye. Simple and acid-modified biosorbents were employed in batch mode processing to remove hazardous basic dyes such as rhodamine-B. Adsorption equilibrium was achieved within 60 min, and treated grapefruit peels (TTCP) were found to be more effective than untreated grapefruit peels (UCP). Kinetic studies outcomes showed that the pseudo-second-order kinetics form fit more with an R2 of ≥ 0.916 and ≥ 0.932 for UCP and TTCP respectively. The adsorption isotherm of Langmuir was used to describe equilibrium for TTCP, with highest sorption ability of 321.507 µg/g. The study also discovered that 1 M HCl and NaOH may be used to regenerate CP, with recovery rates of RhD B reaching up to 98% and 85%, respectively indicating CP is a potential biosorbent for removing RhD B from aqueous solutions.

Batch adsorption experiments were carried out to evaluate the removal of Rhodamine B (RhB), a cationic dye, from synthetic wastewater using a multi-walled carbon nanotube/titanium dioxide (MWCNT/TiO₂)-modified biochar composite (CBTM), with pristine biochar (CCB) as a reference. The effects of solution pH, contact time, adsorbent dosage, temperature, and initial dye concentration on adsorption performance were systematically investigated. Maximum RhB removal occurred at pH 3, with equilibrium achieved after 180 min. Under these conditions, CBTM exhibited a higher adsorption capacity (31.43 mg·g^-1) than CCB (17.31 mg·g^-1) at 313 K. Equilibrium data were best described by the Freundlich isotherm, indicating multilayer adsorption on heterogeneous surfaces, while kinetic analysis showed that the pseudo-first-order model provided the most accurate fit, suggesting a physisorption-dominated process. Thermodynamic parameters (ΔG°, ΔH°, ΔS°) confirmed that the adsorption was spontaneous and endothermic. Interestingly, while CBTM demonstrated superior dye removal, antimicrobial assays revealed stronger bacterial inhibition by CCB. These results highlight the potential of CBTM for efficient dye removal and underscore the multifunctional capabilities of biochar-based adsorbents.

Pontederia cordata, Canna indica, Myriophyllum verticillatum, and Vallisneria natans were selected to investigate the effect and mechanism of plant removal of total nitrogen (TN), total phosphorus (TP), perfluorooctanoic acid (PFOA), and perfluorooctane sulfonate (PFOS) from simulated river water under microplastic stress through hydroponic experiments. The results showed that the four plants had good ability to remove TN, TP, PFOA, and PFOS from simulated river water under microplastic stress. The removal of TN, TP, PFOA, and PFOS by plants under microplastic stress ranged from 57.1% to 80.0%, 48.5% to 67.6%, 42.0% to 68.5%, and 48.0% to 85.3%, respectively. The best removal of TN and TP was achieved by P. cordata with 80.0% and 67.6%, respectively, while PFOA and PFOS were removed by P. cordata at a rate of 42.0% and 48.0%, respectively. M. verticillatum showed the most significant removal of PFOA and PFOS. The uptake of PFOS by plants was better than that of PFOA. Perfluorooctane sulfonate (PFOS) tended to accumulate in plant roots more than PFOA in P. cordata and C. indica. Microplastic stress resulted in a decrease in plant removal of TN, TP, PFOA, and PFOS by 3.9%∼5.3%, 5.4%∼6.9%, 4.9%∼7.2%, and 2.7%∼7.2%, respectively.

In Mexico, oil spills are primarily caused by fuel theft. These incidents have led to the degradation of agricultural soils, with adverse effects on the environment, human health, and the economic development of affected regions. Consequently, biotechnological decontamination techniques have emerged as a promising solution for the restoration of these sites. This study aimed to evaluate the phytoremediation of diesel-contaminated agricultural soils using Gypsophila paniculata and spent Pleurotus spp. substrate as a biostimulant. Additionally, the potential genetic and cellular damage caused by the contaminants present in the soil was assessed before and after the application of biological decontamination treatments. The greenhouse experiment lasted 50 days. Morphological variables of the plants and the total petroleum hydrocarbons (TPH) (mg/kg) were measured, alongside soil toxicity, which was assessed by evaluating the mitotic index (%) and micronucleus frequency (%) in Vicia faba cells. Plants grown with the biostimulant exhibited enhanced morphological characteristics, while the bioremediation treatments achieved diesel removal rates ranging from 29.4% to 46.1%. However, potential genotoxic and cytotoxic effects were observed across all treatments.

Miscanthus × giganteus was tested for textile dye removal. Sorption of Direct Blue 78 was achieved slowly by the leaf (63% after 24 h), while sorption of Basic Red 18 was fast by the stem (96% in an hour). Lignocellulose (24.62% in leaf, 41.34% in fresh and 48.05% in old stem) was responsible for the interaction. FTIR spectra and SEM images of native material and with sorbed dye were similar. Negligible quantities of peroxidases (2 μg/g in old stem) pointed to physical forces underlying sorption. pHpzc for stem-BR18 pair was 5.90 and maximum sorption could be achieved in pH interval 4-9. Desorption and repeated sorption defined maximal binding capacity of 20.8 mg BR18/g of stem. BR18 could be desorbed by only 23% with 0.1 M HCl. Small quantities of zinc (0.71-1.13%), copper (0.74-1.43%) and silicon (0.12-0.28%) were detected without significant difference between samples, as well as chlorine (0.24%) in the sample after desorption and in the sample with sorbed 20.8 mg/g BR18. We propose a more thorough investigation of M. × giganteus as a sorbent of a wider pallet of dyes, as it exerts a potential for such purpose.

Heavy metal contamination is a global issue caused by persistent, toxic, and bioaccumulative elements such as cadmium, lead, arsenic, chromium, and mercury. Unlike organic pollutants, these metals resist biodegradation and accumulate in soils, water, and living organisms, creating severe ecological and health risks. Conventional remediation techniques are expensive, energy-intensive, and produce secondary waste, driving the need for sustainable alternatives. Bioremediation, particularly phytoremediation and mycoremediation, has emerged as an eco-friendly and cost-effective strategy. Recent studies highlight the central role of proteins and peptides in these processes. In plants, metal transporters, metallothioneins, phytochelatins, and redox enzymes regulate the uptake, detoxification, and sequestration of metals, while fungi rely on extracellular enzymes, redox-active metabolites, and cell wall proteins for biosorption and transformation. Advances in protein engineering and synthetic biology now enhance the ability of plants and fungi to target and detoxify metals with greater efficiency. The novelty of this review emphasizes the mechanistic contributions of proteins and peptides to bioadsorption, bioaccumulation, and biotransformation, while addressing current challenges related to scalability, environmental variability, and regulatory acceptance. By integrating synthetic biology, nanobiotechnology, and omics-driven protein discovery, we propose design-based frameworks for next-generation remediation that could transform heavy metal cleanup into predictable, programmable, and field-ready technologies.

A 90-day pot study investigated the effect of low-density polyethylene microplastics (LDPE MPs) on bioaugmented phytoremediation of crude oil-contaminated soil using lemongrass (Cymbopogon flexuosus) and Micrococcus luteus WN01 (PGPR). Plant growth, root morphology, root exudates, microbial population, dehydrogenase activity, residual TPH concentration, and LDPE MP degradation were evaluated. M. luteus significantly increased plant biomass and improved TPH degradation by 79.16% and 64.43%, which were 25.04% and 15.85% higher than uninoculated treatments. M. luteus inoculation still led to higher TPH removal compared to uninoculated treatments despite MP-induced alterations in plant biochemical and morphological traits. GC/MS analysis of lemongrass root exudates showed that M. luteus enriched plants with GABA-associated allelochemicals. FTIR analysis indicated accelerated oxidation of LDPE MPs in planted treatments compared to unplanted ones, evidenced by increased absorbance at characteristic peaks (3620.71 cm^-1 O-H stretching, 1651 cm^-1 C=O stretching, and 1031.10 cm^-1 C-O stretching). This strongly suggests a co-metabolic breakdown of LDPE MPs within the plant rhizosphere (a degradation hotspot). Lemongrass essential oil was not significantly affected by the contaminant or M. luteus. This study highlights the lemongrass-M. luteus association as a promising candidate for the remediation of both petroleum- and MP-contaminated soil, with the added benefit of essential oil production.