Industrial by-products provide materials for remediation measures. In this study, a silicon-iron amendment was prepared from residue originating from acid-extracted copper (Cu) tailings based on thermal activation at temperatures ranging from 550 °C to 1150 °C for 30 min with the use of additives (CaO, Na₂CO₃, NaOH). The remediation performance of the amendment was evaluated through soil incubation and greenhouse pot experiments with vetiver (Vetiveria zizanioides). The results showed that the highest levels of soluble Si (6.11% of the total Si) and Fe (2.3% of the total Fe) in the amendment were achieved with thermal activation at 1150 °C for 30 min using an optimal ratio between residue and additives (residue: CaO: Na₂CO₃: NaOH = 1: 0.4: 0.4: 0.2). Heavy metal release indicated that the amendment could be safely used for soil remediation. The incubation experiments showed that the DTPA-extractable Cd, Cr and Pb in contaminated soils decreased with increasing amendment rate, which was not observed for As. The amendment-induced decrease in the Cd, Cr and Pb availability in contaminated soils could be explained by pH-change induced immobilization, Fe-induced chemisorption, Si-induced co-precipitation, and Ca-induced ion exchange. Correlation analysis suggested that there were significant negative correlations between DTPA-extractable Cd, Cr and Pb and the pH, Fe, Si, and Ca in soil pore water and soil. The most suitable amendment rate was determined to be 1% by balancing the efficacy and wise utilization of the amendment. The pot experiment demonstrated that the amendment promoted the vetiver growth and stimulated the accumulation of Cd and Cr in the roots. The amendment was proved to be promising for the phytostabilization of Cd, Cr and Pb in contaminated soils. Further investigations are required to determine whether the amendment is a tool for the long-term remediation of multi-metal-contaminated soils at the field scale.

In order to select appropriate plant species for phytoremediation of explosive compounds, phytotoxicity, uptake proficiency, capability of the plant to degrade/transform the compounds, and several environmental factors need to be considered. The environmental factors comprise climatic attributes, soil type, the water environment, root penetration depth, contaminant kinetics, and bioavailability. Out of the plant species that have shown efficient TNT uptake, there are only a few that can do so in a variety of environments, which is imperative in case of contaminants that are widespread, such as TNT and RDX. The two most effective species for TNT uptake reported to date are Eurasian water milfoil, Myriophyllum spicatum and vetiver grass, Chrysopogon zizanioides. For RDX phytoremediation, reed canary grass, fox sedge, and rice have shown promise, although degradation of RDX in the plant tissue is limited. Over the past few decades, a considerable amount of information on phytotoxicity and metabolism of TNT and RDX in plants and microorganisms have been collected, which has led to the identification of potential plant species for use in TNT and RDX phytoremediation, as well as candidate genes for developing effective transgenic plants. Recent research has also revealed promising non-transgenic approaches, such as use of chaotropic agents for enhanced solubilization and uptake of TNT, which could prove to be practical and effective for military sites. Field trials of some of these promising new technologies are necessary for the development of effective, low-cost, and environmentally friendly phytoremediation of explosive-contaminated sites.

Heavy metal pollution in the environment compromises environmental quality and human health. Phytoremediation is an innovative, green, and affordable technique that uses plants for the removal of contaminants from soil and water. Finding suitable plants that can adequately remove heavy metals from both soil and water has been a research hotspot in recent years, and there has been a rapid development in research on the use of high biomass producing crops for this purpose. Vetiver grass and Indian mustard have emerged as plants that are effective for phytoremediation and can serve other purposes during and after their use in phytoremediation. These plants are applicable in many areas because they can tolerate varied climatic conditions, thrive on degraded lands and contaminated water bodies, are easy to cultivate, and produce high biomass. This review article evaluates the phytoremediation potential of vetiver grass and Indian mustard by providing a synthesis of studies that have investigated their use for this purpose. The review considered research articles from the past 21 years and highlights the status and possible advancements in the efficient use of these plants for the remediation of heavy metal–contaminated sites. This work is of importance because phytoremediation is still undergoing immense research to promote its applicability and acceptability. Thus, it gives information on two important plants that are very useful for phytoremediation.

In many areas, wastewater feeds water bodies, which leads to it being non-usable for agricultural and other uses. Phytoremediation is a scientific approach which cleans contaminated waters, demanding large areas for application. Vertical agriculture is a new method to compact plant cultures. This study investigates vertical wastewater phytoremediation (VWP). Twenty vetiver grasses were planted in a hydroponic vertical agriculture system. Wastewater flowed into the system in four different flow rates, 60, 80, 100, and 160 l day⁻¹ and water purity was assessed in order to measure the remediation ability of the VWP. Results showed a reduction in biochemical oxygen demand (BOD5 and NO₃⁻ concentrations and an increase of electrical conductivity (EC) and dissolved oxygen (DO) in the outlet. Maximum and minimum (BOD5) reduction percentage (78.47% and 67.36%) and NO₃⁻ removal percentage (90.53% and 36.41%) occurred in flow rates 60 and 160 l day⁻¹, respectively. With the increase of wastewater flow rate, phytoremediation performance decreased, but the performance of VWP with vetiver grass was efficient enough to enable wastewater remediation. Scaling up VWP with Vetiver and related competitive plant species holds promise for wastewater remediation for both human and ecosystem services.

This study reports organics and nutrient removal performances of the intensified constructed wetlands, i.e., tidal flow-based microbial fuel cell (MFC) and tidal flow wetlands that received municipal wastewater. The wetland systems were filled with organic (coco peat, biochar) or waste (Jhama brick, steel slag) materials, planted with Phragmites australis or Chrysopogon zizanioides (Vetiver) species, and operated under three flood periods: 8, 16, 24 h. Input ammonia nitrogen (NH₃–N), total nitrogen (TN), phosphorus (P), chemical oxygen demand (COD), and biochemical oxygen demand (BOD) load across the wetland systems ranged between 3–27, 12–78, 0.1–23, 36–1130, and 11–281 g/m²day, respectively; mean removal percentages were 60–83, 74–84, 95–100, 94–98, and 93–97%, respectively, throughout the experimental run. The wetland systems achieved similar organics and P removals; operational and media variation did not influence removal kinetics. All wetland systems achieved the highest TN removal (76–87%) when subjected to 24-h flood period. TN removal performances of waste material–based wetlands were comparable to organic media-based systems. Tidal flow-based MFC wetlands achieved better TN removal than tidal flow wetlands because of supplementary electron production through fuel cell–based organics degradation kinetics. Maximum power production rates across the tidal flow-based MFC wetlands ranged between 53 and 57 mW/m². Monod kinetics–based continuous stirred tank reactor (CSTR) models predicted NH₃–N, TN, and COD removals (in wetland systems) more accurately. Kinetic models confirmed the influence of substrate (i.e., pollutant) and environmental parameters on pollutant removal routes.

Vetiver has a broad history of traditional medicinal uses, but only a handful of research article has reported its utility in treating diseases. But unfortunately, no work has been reported on the anti-inflammatory activity of its plant extract and inflammatory-linked diseases. Hence, the present review focuses on investigating the several presumptions which can be put forward to explain its anti-inflammatory property. Thus, for ensuring the same, all the databases like science direct, PubMed, book chapters, and other authenticated papers were thoroughly studied to present a connection between inflammation and the plant potential. After gaining enough knowledge on pathogenesis of inflammation, it has been observed that the release of mediators from the arachidonic acid metabolism pathway and generation of oxidative and nitrogen species are presented as the main reason for the occurrence of inflammation condition. The stimulation of antioxidant enzyme system network by the plant extract reduces the level of oxidative stress, creating a balance between oxidant and antioxidant system. Moreover, its antimicrobial activity will prevent the biological source of stimulation towards injury and the CNS depressant effect will subside the pain of inflammation. Amalgamating all the factors together, the plant can be utilized as anti-inflammatory can be and also can be proved as a beneficial perspective in the treatment of inflammation-linked disorders.

Phytoremediation is an attractive, economic alternative to soil removal and burial methods to remediate contaminated soil. However, it is also a slow process. The effect of humic acid in enhancing B and Pb phytoextraction from contaminated soils was studied (pot experiment) using transplanted vetiver grass (Vetiveria zizanioides (L.) Nash). Boron was applied at 0, 45, 90 and 180 kg B ha-¹ soil (as H₃BO₃) in 16 replicates. Of the 64 pots, four pots each were treated with 0, 100, 200 and 400 kg ha-¹ humic acid (HA) solution. In a separate experiment, Pb was applied (as Pb(NO₃)₂) at 0, 45, 90 and 180 kg Pb ha-¹ prior to addition of HA solutions at levels identical to the B experiment. Experiments were conducted using a randomized complete block design with four replicates. Vetiver grass was harvested 90 days after planting. Lead addition beyond 45 kg Pb ha-¹ decreased Pb uptake mostly due to a yield decline. Humic acid application increased Pb availability in soil and enhanced Pb uptake while maintaining or enhancing yield. An application of 200 kg HA ha-¹ was optimal for maintaining yield at elevated Pb levels. Boron application did not impact yield but greatly increased B content of roots and shoot. Boron uptake was greatest upon addition of 400 kg HA ha-¹. We conclude that HA addition to vetiver grass can be an effective way to enhance phytoremediation of B and Pb but optimum rates differ depending on soil B and Pb contamination levels.

India’s fast industrialization and population expansion have resulted in heavy metal accumulation from many operations, which has caused massive waste generation and poisoning of soils. Therefore, it is necessary to design reclamation to improve th T.Ne soil. Phytoremediation presents itself as a viable, economical, and environmentally sustainable solution to this problem. This study was carried out by using plants namely, aloe-vera (Aloe-Barbadensis), tulsi (Ocimum Tenuiflorium), and vetiver (Chrysopogon Zizanoides) plants which were planted in a simulated soil of Cd, Zn and Pb, for 4 weeks. The sample of plant and soil were taken in 9 different pots, (15 cm diameter and 25 cm height) among 9 potted soils one will be tested as a controlled sample. An aqueous solution of lead, cadmium and zinc were added separately to the dry soil samples. The moisture level of the soil was maintained to near field water capacity (35.6%) and equilibrated for two weeks. The saplings of vetiver grass, aloe vera and tulsi were selected and pruned (the shoots were originally 20 cm high and the roots 8 cm long), and then transplanted into the pots. The AAS test was conducted after 4 weeks of growing in simulated soil. Tulsi demonstrated the highest efficacy in reducing Zn concentrations from 300 mg/kg to 188.3 mg/kg, followed by vetiver (179.3 mg/kg) and Aloe vera (158.3 mg/kg). Similarly, for Pb, tulsi exhibited the most substantial reduction (from 600 mg/kg to 188.3 mg/kg), followed by vetiver (164.3 mg/kg) and Aloe vera (179.6 mg/kg). Regarding Cd, tulsi reduced concentrations from 80 mg/kg to 18.62 mg/kg, while vetiver achieved a 17.62 mg/kg reduction. The result highlights Tulsi’s superior remediation potential, attributed to its efficient heavy metal uptake and translocation mechanisms. Thus, using these plants in the phytoremediation process, the heavy metals are extracted more economically than other plants. This technique highlights the innate ability of hyper-accumulator plant species, which flourish in situations high in heavy metals, to extract contaminants from contaminated soil.

Vetiver is a traditional plant with versatile applications in medicine, aroma, commerce, environmental-protection, and agriculture. This review was designed to compile all the latest information on phytochemistry, pharmacology, and traditional uses of C. zizanioides. All the information related to this plant was gathered from several authentic sites, using keywords like Chrysopogon zizanioides, Vetiveria zizanioides, Khus, and Khas-Khas. The included resources were journaled articles, book chapters, books, Ayurvedic Pharmacopoeias, and Ayurvedic Formulary of India, from science direct, PubMed, research gate etc. All the necessary, relevant, authentic, and updated information were tried to inculcate in the manuscript. The literature was collected via online sites like Pub med, Scopus, and Science direct as well. During compilation, it observed that many traditional utilities of vetiver got their authentication when tested using different disease-based pharmacological models taking various extracts of roots, leaves, and root oil as test samples. However, systematic studies for isolation of active constituents and establishing their mechanism of action are still required to be validated. On the other hand, the development of novel and robust techniques needed for oil extraction can further enhance the exploration of biological utilities faster. Moreover, the cultivators and harvesters must address carefully to prevent the linked drawback of soil erosion.

Two cadmium-resistant bacteria, Ralstonia sp. TAK1 and Arthrobacter sp. TM6, produced exopolymers that promoted cadmium solubilization in contaminated soil. The enhancement of cadmium uptake and accumulation in a monocot (Vetiveria nemoralis, vetiver grass) and a dicot (Ocimum gratissimum, African basil) was investigated in a greenhouse study. Compared with the uninoculated control, Ralstonia sp. TAK1 and Arthrobacter sp. TM6 increased cadmium accumulation in the roots and shoots of V. nemoralis. These cadmium-resistant bacteria increased the cadmium content of whole V. nemoralis plants similarly to ethylenediaminetetraacetic acid (EDTA) treatment alone. In contrast, only Arthrobacter sp. TM6 enhanced cadmium accumulation in the roots and shoots of O. gratissimum. The highest cadmium content of whole O. gratissimum plants was observed when the plant was treated with EDTA following treatment with Arthrobacter sp. TM6. The phytoextraction coefficient and translocation factor (TF) of bacteria-inoculated V. nemoralis were higher than those of O. gratissimum. Arthrobacter sp. TM6 increased the phytoextraction coefficients and TFs in V. nemoralis and O. gratissimum. These results indicate that Arthrobacter sp. TM6 and both tested plant species promote cadmium phytoextraction in contaminated soil.