The toxicity is produced for living organisms when the nanomaterials are developed in the natural ecosystem either naturally or if introduced by humans. Nevertheless, there is a huge gap in the research of this area, and investigations are being conducted to determine the potential detrimental impacts of the nanomaterials and the means of eliminating the potential toxicities. In our research, we investigated the potential of zinc oxide nanoparticle (ZnONPs) tolerant Trichoderma pseudoharzianum T113 strains in reducing the toxicity of ZnO NPs in tomato crops. Our research findings of a very thoroughly investigated experiment on mechanism of action revealed that application of T113 in NPs amended soil triggered an appreciable change in the microbial diversity of the soil and improved the population density and diversity of the growth-promoting soil microbes and fungi that produced glomalin, a protein responsible for metal chelating. The amount of glomalin in the soil was significantly improved in soil by T113 strain inoculation. The diversity and abundance of the microbes, having beneficial impacts on plants and the glomalin in soil, drastically reduced the NPs induced toxicity under the application of the T113 strain of T. pseudoharzianum. Plants inoculated with the T113 strain, when grown in NPNP-contaminated soil, exhibited increased growth, enhanced antioxidant activities, improved photosynthesis, and a decline in damage induced by oxidative stress and the accumulation and translocation of Zn. Moreover, applying the T113 strain also reduced the Zn bioavailability in soil contaminated with NPs. These research findings are an eco-friendly and sustainable solution to the ZnO NP toxicity in the host plants.

Plastic pollution is a universal problem, and microbial management of plastic waste represents a promising area of biotechnological research. This study investigated the ability of bacterial strains which were isolated from landfill soil to degrade Low-Density Polyethylene (LDPE). Strains obtained via serial dilution were screened for LDPE degradation on Minimal Essential Medium (MEM) with hexadecane. Nine isolates producing clearance zones on hexadecane-supplemented MEM were further tested for biofilm formation on LDPE sheets. High cell surface hydrophobicity isolates (>10%) were selected for detailed biodegradation studies. The C-8 bacterial isolate showed the highest LDPE weight loss (3.57%) and exhibited maximum laccase (0.0219 U/mL) and lipase activity (19 mm) among all bacterial isolates after 30 days. Weight loss was further validated by FTIR and SEM analysis. FTIR analysis revealed that in comparison to control, changes in peak were observed at 719 cm-1 (C-H bending), 875.67 cm-1 (C-C vibrations), 1307.07 cm-1 (C-O stretching), 1464.21 cm-1 (C-H bending), 2000-1650 cm-1 (C-H bending), 2849.85 cm-1 (C-H stretching) in microbial treated LDPE sheets. The treated LDPE also displayed increase in carbonyl index (upto 2.5 to 3 folds), double bond index (1 to 2-fold) and internal double bond index (2 to 2.5-fold) indicating oxidation and chain scission in the LDPE backbone. SEM analysis showed substantial micrometric surface damage on the LDPE film, with visible cracks and grooves. Using 16S rRNA gene sequencing, the C-8, C-11, C-15 and C-19 isolate were identified as Bacillus paramycoides, Micrococcus luteus, Bacillus siamensis and Lysinibacillus capsica, respectively.

Biogrouting, a method to enhance soil properties using microorganisms and mechanical techniques, has shown great potential for soil improvement. Most studies focus on small sand columns in labs, but recent tests used 0.5 m plastic boxes filled with sand stabilized with microorganisms and fly ash. The experiments, conducted over 30 days, applied injection and infusion methods with microbial fluids, maintaining groundwater levels to simulate field conditions. Mechanical properties were analyzed through unconfined compressive strength (UCS) tests on extracted samples. Researchers also assessed calcium carbonate distribution and shear strength. Results showed water saturation significantly influenced vertical stress (qu), while UCS correlated with the permeability of sand containing varying calcium carbonate levels. Bacillus safensis, a resilient bacterium used in this process, can withstand extreme conditions. After completing its task, it enters a dormant state and reactivates when needed. The bacteria produce calcium carbonate by binding calcium with enzymes, which cements soil particles, enhancing strength and stability. center dot Testing enzymes on microbes and natural soil center dot Installation settings for drip tools using infusion center dot Soil resistance testing after stabilization using UCS

In today's highly competitive and interconnected global market, economic achievement and prosperity are essential needs for every individual. However, in recent years, the science of sustainability has gained popularity due to mounting evidence of the damaging impacts of environmental issues. Lately, the expansion of petroleum industries and refineries has led to a substantial rise in the production of refinery oily waste. The treatment of such waste presents significant environmental challenges, necessitating the development of sustainable solutions. This review explores the latest advancements in biological processes for treating it, focusing on their efficacy and limitations. These processes are still facing challenges such as slow degradation rates, nutrient availability, and pollutant toxicity, which can hinder efficiency. To address these, efforts are being made to develop more viable biological treatments including exploration of microbial strains, optimizing process conditions, bioreactor systems, and integrating advanced bioremediation techniques. Potential applications of these processes across different contaminated sites are discussed along with commercially available technologies. Drawbacks related to bioprocess scale-up, cost-effectiveness, and regulatory constraints are also addressed. Additionally, it incorporates pertinent case studies that serve as illustrations of successful implementations of biological strategies. Ultimately, this sets the stage for practical bioremediation implementation as a solution for refinery waste management.

Heavy metal (HM) pollution in agricultural soils threatens plant growth and food security, underscoring the urgency for sustainable and eco-friendly solutions. This study investigates the potential of endophytic fungi, Fusarium proliferatum SL3 and Aspergillus terreus MGRF2, in mitigating nickel (Ni) and cadmium (Cd) stress in Solanum lycopersicum (tomato). These fungi were evaluated for their plant growth-promoting traits, including the production of indole-3-acetic acid (IAA) and siderophores, offering a sustainable strategy for alleviating HM toxicity. Inoculation with SL3 and MGRF2 significantly reduced metal accumulation in plant tissues by enhancing metal immobilization and modifying root architecture. Microscopic analysis revealed that fungi protected root epidermal cells from Ni- and Cd-induced damage, preserving cellular integrity and preventing plasmolysis. Fungal-treated plants exhibited improved growth and biomass, with SL3 demonstrating superior Cd stress mitigation and MGRF2 excelling under Ni stress. Photosynthetic pigment levels, including chlorophyll-a and carotenoids, were restored, highlighting the role of fungi in maintaining photosynthetic efficiency. Antioxidant activity was also modulated, as reduced glutathione (GSH) levels and increased flavonoid production were observed, contributing to enhanced oxidative stress management. Hormonal profiling revealed that fungal inoculation balanced stress-induced hormonal disruptions, with lower abscisic acid (ABA) levels and improved salicylic acid (SA) and gibberellic acid (GA) pathways. These changes facilitated better stress adaptation, enhanced nutrient uptake, and improved physiological performance. qRT-PCR analysis further revealed differential gene expression patterns, while antioxidant enzyme activity strengthened the plants' defense against HMinduced oxidative damage. Multivariate analyses highlighted shoot and root traits as critical indicators of resilience, with fungal inoculation driving substantial improvements. These findings demonstrate the potential of SL3 and MGRF2 as eco-friendly bioinoculants, offering a sustainable and cost-effective approach to reducing HMs toxicity in contaminated soils while enhancing crop productivity. This work highlights the promising role of plant-microbe interactions in advancing sustainable agriculture and addressing the challenges posed by heavy metal pollution.

Rampant industrial growth and urbanization have caused a wide range of hazardous contaminants to be released into the environment resulting in several environmental issues that could eventually lead to ecological disasters. The unscientific disposal of urban and industrial wastes is a critical issue as it can cause soil contamination, bioaccumulation in crops, groundwater contamination, and changes in soil characteristics. This article explores the impact of various industrial and urban wastes, including petroleum hydrocarbons (PHs), coal-fired fly ash, municipal solid waste (MSW) and wastewater (MWW), and biomedical waste (BMW) on various types of soil. The contamination and impact of each of these wastes on soil properties such as compaction characteristics, plasticity, permeability, consolidation characteristics, strength characteristics, pH, salinity, etc is studied in detail. Most of the studies indicate that these wastes contain heavy metals, organics, and other hazardous compounds. When applied to the soil, PHs tend to cause large settlements and reduction in plasticity, while the effect of coal-fired fly ash varies as it mainly depends on the type of soil. From the studies it was seen that the long-term application of MWW improves the soil health and properties for agricultural purposes. Significant soil settlements were observed in areas of MSW disposal, and studies show that MSW leachate also alters soil properties. While the impacts of direct BMW disposal have not been extensively studied, few researchers have concentrated on utilizing certain components of BMW, like face masks and nitrile gloves to enhance the geotechnical characteristics of weak soil. Soil remediation is required to mitigate the contamination caused by heavy metals and PHs from these wates to improve the soil quality for engineering and agricultural purposes, avert bioaccumulation in crops, and pose less environmental and public risks, and ecotoxicity. Coal-fired fly ash and biomedical waste ash contain compounds that promote pozzolanic reactions in soil, recycling and reuse as soil stabilizers offer an effective strategy for their reduction in the environment, thus complying to sustainable practices. In essence, this study offers a contemporary information on the above aspects by identifying the gaps for future research and mitigation strategies of contaminated soils.

Chlorpyrifos contamination is a currently on-going issue with significant environmental impacts. As such, rapid and effective techniques that remove chlorpyrifos from the environment are urgently required. Here, a strain of Pseudomonas nitroreducens W-7 exhibited exceptional degradation ability towards both chlorpyrifos and its major metabolite 3,5,6-trichloro-2-pyridinol (TCP). W-7 can effectively reduce the toxicity of chlorpyrifos and TCP towards a variety of sensitive organisms through its superior degradation capacity. W-7 demonstrated efficient soil bioremediation by removing over 50 % of chlorpyrifos (25 mg/kg) from both sterile and non-sterile soils within 5 days, with significantly reduced half-lives. Additionally, 16S rDNA high-throughput sequencing of the soil revealed that the introduction of W-7 had no significant impact on the soil microbial community. A pivotal hydrolase Oph2876 containing conserved motif (HxHxDH) and a bimetallic catalytic center was identified from W-7. Oph2876 was a heat- and alkali-resistant enzyme with low sequence similarity (< 44 %) with other reported organophosphorus hydrolases, with a better substrate affinity for hydrolysis of chlorpyrifos to TCP. The molecular docking and site-directed mutagenesis studies indicated that the amino acid residues Asp235, His214, and His282, which were associated with the conserved sequence HxHxDH, were crucial for the activity of Oph2876. These findings contribute to a better understanding of the biodegradation mechanism of chlorpyrifos and present useful agents for the development of effective chlorpyrifos bioremediation strategies.

Since the beginning of their production and use, fossil fuels have affected ecosystems, causing significant damage to their biodiversity. Bacterial bioremediation can provide solutions to this environmental problem. In this study, the new species Isoptericola peretonis sp. nov. 4D.3T has been characterized and compared to other closely related species in terms of hydrocarbon degradation and biosurfactant production by in vitro and in silico analyses. Biosurfactants play an important role in microbial hydrocarbon degradation by emulsifying hydrocarbons and making them accessible to the microbial degradation machinery. The tests performed showed positive results to a greater or lesser degree for all strains. In the synthesis of biosurfactants, all the strains tested showed biosurfactant activity in three complementary assays (CTAB, hemolysis and E24%) and rhamnolipid synthesis genes have been predicted in silico in the majority of Isoptericola strains. Regarding hydrocarbon degradation, all the Isoptericola strains analyzed presented putative genes responsible for the aerobic and anaerobic degradation of aromatic and alkane hydrocarbons. Overall, our results highlight the metabolic diversity and the biochemical robustness of the Isoptericola genus which is proposed to be of interest in the field of hydrocarbon bioremediation.

Asbestos is a silicate mineral that occurs naturally and is made up of flexible fibres that are resistant to heat, fire, and chemicals and do not conduct electricity. Both anthropogenic disturbance and natural weathering of asbestos-containing waste materials (ACWMs) can result in the emission of asbestos fibre dust, which when breathed, can cause asbestosis, a chronic lung illness that happens due to prolonged exposure of such fibre dust, and can cause 'mesothelioma' cancer. Although asbestos mining and its utilisation had been banned in many countries, there is still a significant issue of ACWMs disposal in the built environment and abandoned sites. It is neither practical nor economical to safely eliminate ACWMs from the built environment, and it is estimated that globally, 4 billion metric tonnes of ACWMs require safe management strategies. The toxicity of inhaled asbestos fibre relies on its surface properties, and in particular the distribution of iron, which serves a critical role in pathogenicity by forming reactive free radicals that damage DNA, thereby trigging cancer. Examining the usefulness of higher plants and microbes in the bioremediation of soil contaminated with ACWMs is the prime aim of the review. Higher plants and microorganisms such as lichens, fungi, and bacteria often play a major role in the remediation of soil contaminated with ACWMs by facilitating the bioweathering of asbestos and the removal of iron to mitigate the toxicity of asbestos.

Heavy metal compounds are used in a variety of industrial processes, including tanning, chrome plating, anti-corrosion treatments, and wood preservation. Heavy metal ion pollution in water and wastewater is often caused by industrial effluent discharge into open water sources. Toxic heavy metal ions such as As (III), Cr (VI), Cd (II), and Pb (II) are well-known and enter the body through a variety of pathways, including the food chain, respiration, skin absorption, and drinking water. These heavy metal ions produce oxidative stress in cells, resulting in cell organelle destruction. Heavy metals produce toxicity and may cause genetic material mutation or change, histone modification, and epigenetic alteration at various stages. Furthermore, heavy metals are linked to heart failure, renal damage, liver failure, and a variety of skin problems. For heavy metals cleanup, several standard approaches are utilized. Nonetheless, these technologies are costly and result in toxic sludge after treatment. As a result, there is an urgent need for an appropriate, environmentally safe, and efficient heavy metal removal technology. For heavy metal removal, microbial-based approaches are regarded as both environmentally benign and cost-effective. This review focuses on heavy metal pollution in water, its harmful consequences, and heavy metal cleanup by microbiological means.