Bioremediation Of Environments Research Articles

Bioremediation of heavy metal-contaminated environment: developed strategies and potential use of biosurfactants as chelators

Abstract Heavy metal pollution damages the ecosystems and presents a major problem for public health. Thus, an urgent need was developed to decrease the high levels of heavy metals in the soil and aquatic environments. With this aim, numerous physicochemical strategies were developed. However, they are money-consuming, require the use of energy and chemical additives and can release secondary compounds that can pollute and cause great damage to the environment. Then, biological methods based on the investigation of bacteria, fungi and plants along with their derived secondary active metabolites became the best alternatives. Using plant capacities, different phytoremediation strategies were developed such as phytoextraction, phytovolatilization, rhizofiltration and phytostabilization. Regarding bioremediation, bacterial biosorption of heavy metals, biolixiviation and lagooning offer great potential for their environmental cleaning. Additionally, the use of secondary active metabolites, such as biosurfactants, is well-studied. Generally, they are a class of structurally very varied molecules commonly synthesized by many microorganisms with amphiphilic character. Owing to their anionic charge, they have the capacity to sequestrate heavy metals permitting their elimination. Glycolipids and lipopeptides are among the most recognized biosurfactants with interesting heavy metal chelating properties.

Assessment and Biodegradation of Polycyclic Aromatic Hydrocarbons in Soil and Water Around Petroleum Products Depot Suleja, Nigeria.

Petroleum contamination constitutes a frequent incidence in various petroleum depots in Nigeria. In this study, the polycyclic aromatic hydrocarbons (PAHs) present in soil and water in communities around Petroleum Products Marketing Company (PPMC) Suleja, Nigeria, were evaluated and degraded using indigenous microorganisms. The samples sites were divided into 7 plots from where samples of water and soil were obtained: one within the PPMC depot, five from communities surrounding the depot, and the control 93,000km from the depot. The microbial counts were determined using spread plate inoculation technique on minimal salt media. The microbial isolates were characterized and identified based on their cultural, biochemical, and molecular characteristics. The potential of the microbial isolates to utilize 0.05 mL of diesel, kerosene, engine oil, and crude oil was determined in a Bushnell Haas Broth, and the biodegradation was determined by total viable cell counts and spectrophotometry. The ability of the isolates to mineralize PAHs was also evaluated in a minimum salt media. The bacterial isolates were species of Streptococcus, Pseudomonas, Staphylococcus, Proteus, Escherichia, and Bacillus, while species of Penicillium, Aspergillus, Mucor, and Rhizopus were isolated among the fungi. Aspergillus niger strain ATCC 1015 and Bacillus thuringiensis strain M43 showed high capacity to utilize the 16 priority PAHs. The pahE1 gene was used by Bacillus thuringiensis, Pseudomonas aeruginosa and A. niger, while Penicillium notatum used pahE2 gene for the degradation of the PAH. The current study identified microbial isolates that can utilize priority PAHs, making them beneficial for oil spill bioremediation in tropical environments.

Lignin precursors enhance exolaccase-started humification of bisphenol A to form functional polymers

Humification plays a significant role in converting phenolic pollutants and forming heterogeneous polymers, but few studies have been performed to investigate exolaccase-started humification (ESH). Herein, the influences of lignin precursors (LPs) on exolaccase-induced bisphenol A (BPA) removal and humification were explored. In particular, the architectural features and botanical effects of the formed humification products were also tested. ESH was extremely beneficial in boosting BPA removal in the presence of LPs. Compared with LP-free (58.49%), 100% of BPA was eliminated after the reaction with ESH for 72 h. Such a process was controlled by an exolaccase-caused random assembly of radicals, which generated a large number of hydrophobic polymers through nonspecific covalent binding of C–C and/or C–O. These humified polymers were extremely stable at pH 2.0–10.0 and −20 °C to 80 °C and displayed unique functions, i.e., scavenged 2,2-diphenyl-1-picrylhydrazyl/2,2′-azino-bis3-ethylbenzothiazoline-6-sulphonic acid radicals and exerted antioxidant capacities. More importantly, the functional polymers could act as auxin analogs to increase the germination index (>100%), plant biomass, and salt tolerance of radish seedlings. Our findings disclosed that ESH could not only be optimized to mitigate the ecological risks of phenolic pollutants and sequester organic carbon in environmental bioremediation, but the resulting abundant auxin analogs also contributed to agricultural productivity.

Antibiotic and Heavy Metal Co-Resistant Strain Isolated from Enrichment Culture of Marine Sediments, with Potential for Environmental Bioremediation Applications.

Antibiotics and heavy metals have caused serious contamination of the environment and even resulted in public health concerns. It has therefore become even more urgent to adopt a sustainable approach to combating these polluted environments. In this paper, we investigated the microbial community of marine sediment samples after 255 days of enrichment culture under Cu (II) and lincomycin stress and ZC255 was the most resistant strain obtained. The 16S rRNA gene sequence confirmed that it belonged to the genus Rossellomorea. Strain ZC255 was resistant to 12 kinds of antibiotics, and had a superior tolerance to Cu (II), Pb (II), Ni (II), Zn (II), Cr (III), and Cd (II). Moreover, it exhibits strong bioremoval ability of Cu and lincomycin. The removal efficiency of Cu (II) and lincomycin can achieve 651 mg/g biomass and 32.5 mg/g biomass, respectively. Strain ZC255 was a promising isolate for pollution bioremediation applications.

Shrimp laccase degrades polycyclic aromatic hydrocarbons from an oil spill disaster in Brazil: A tool for marine environmental bioremediation

Our work aims to purify, characterize and evaluate a laccase from by-products of the shrimp farming industry (Litopenaeus vannamei) for the degradation of Polycyclic Aromatic Hydrocarbons (PAHs) from 2019 oil spill in Brazilian coast. The enzyme was purified by affinity chromatography and characterized as thermostable, with activity above 90 °C and at alkaline pH. In addition, the laccase was also tolerant to copper, lead, cadmium, zinc, arsenic, hexane and methanol, with significant enzymatic activation in acetone and 10 mM mercury. Concerning PAHs' degradation, the enzyme degraded 42.40 % of the total compounds, degrading >50 % of fluorene, C4-naphthalenes, C3-naphthalenes, C2-naphthalenes, anthracene, acenaphthene, 1-methylnaphthalene and 2-methylnaphthalene. Thus, this laccase demonstrated important characteristics for bioremediation of marine environments contaminated by crude oil spills, representing a viable and ecological alternative for these purposes.

Biodegradation of Waste Lubricant Oil by a Novel Isolated Biosurfactant Producer- Achromobacter xylosoxidans PSA5

Waste lubricant oil (WLO) is a critical environmental issue because of its recycle and disposal challenges. A potent biosurfactant-producing bacterial strain was isolated by the enrichment culture technique using WLO as the sole carbon source from the oil-contaminated soils. The strain was identified as Achromobacter xylosoxidans (NCBI GenBank accession number: MW673656) based on the morphological, biochemical, and 16S rRNA gene sequencing. The preliminary characterization of the produced biosurfactant by biochemical methods revealed its glycolipid nature. The strain possessed extensive biodegradative potential and degraded various components present in WLO. The gas chromatography-mass spectrometry (GC-MS) analysis showed that the strain could degrade hydrocarbons (C7-C22) and diethyl phthalate, a priority pollutant, with a relative degradation of 43.87% within 7 days of incubation. The biodegradation of WLO by the strain confers its use in the bioremediation of oil-polluted environments, and the simultaneous biosurfactant production is undoubtedly a step toward greener technology.

Short Peptides for Hydrolase Supramolecular Mimicry and Their Potential Applications.

Hydrolases are enzymes that have found numerous applications in various industrial sectors spanning from pharmaceuticals to foodstuff and beverages, consumers' products such as detergents and personal care, textiles, and even for biodiesel production and environmental bioremediation. Self-assembling and gelling short peptides have been designed for their mimicry so that their supramolecular organization leads to the creation of hydrophobic pockets for catalysis to occur. Catalytic gels of this kind can also find numerous industrial applications to address important global challenges of our time. This concise review focuses on the last 5 years of progress in this fast-paced, popular field of research with an eye towards the future.

Engineering a biofilters microbiome with activated carbon and bioaugmentation to improve stormwater micropollutant removal

Harnessing prokaryotes’ metabolic capacity and adaptive potential is of interest for environmental bioremediation and biological treatment of domestic and industrial waste. Bioaugmentation is commonly implicated in the cleanup of high-dosed environmental pollution. In this study, Arthrobacter aurescens TC1 was used to augment biofiltration systems for bioremediation of stormwater micropollutant. Bioaugmentation was tested on non-vegetated and vegetated system designs, with or without an adsorbent biocarrier [granulated activated carbon (GAC)]. This study investigated how system design affects microbial function and structure. It focused on long-term metabolic responses of the biofilter’s microbiome to low chronic exposure to the herbicide atrazine and fluctuations in atrazine load. Shotgun metagenomics analyses demonstrated that the major contributor to microbiome structure was the supplementation of GAC. Vegetation affected microbiome structure mainly in sand biofilter-media. GAC showed a significant shift in atrazine-degrading genes over time compared to sand. Diversity and richness increased with time in all system designs, regardless of atrazine load fluctuations. To conclude, incorporating GAC in stormwater-biofiltration systems effectively enhances the micropollutant-biodegradation capacity in stormwater with negligible effects on the biofilter’s microbiome diversity and function.

Melanin biopolymers from microbial world with future perspectives-a review.

Melanin is an amorphous polymer made of heterogeneous functional groups synthesized by diverse organisms including fungi, bacteria, animals, and plants. It was widely acknowledged for its biological processes and its key role in the protection of organisms from environmental stress. Recently, melanin clutches attention in the field of nanobiotechnology, drug delivery, organic semiconductors and bioelectronics, environmental bioremediation, photoprotection, etc., Furthermore, melanin from natural sources like microbial community shows antimicrobial, fighting cancer, radical scavenging, cosmeceuticals, and many therapeutic areas as well. Though the multipotentiality nature of melanin has been put forth, real-world applications still flag fall behind, which might be anticipated to the inadequate and high price essence of natural melanin. However, current bioprocess technologies have paved for the large-scale or industrial production of microbial melanin, which could help in the replacement of synthetic melanin. Thus, this review emphasizes the various sources for melanin, i.e., types-based on its pathways and its chemical structures, functional efficiency, physical properties, and conventional and modern methods of both extraction and characterization. Moreover, an outlook on how it works in the field of medicine, bioremediation, and other related areas provides perspectives on the complete exploitation of melanin in practical applications of medicine and the environment.

Genomic and biotechnological potential of a novel oil-degrading strain Enterobacter kobei DH7 isolated from petroleum-contaminated soil

In this study, a novel oil-degrading strain Enterobacter kobei DH7 was isolated from petroleum-contaminated soil samples from the industrial park in Taolin Town, Lianyungang, China. The whole genome of the strain was sequenced and analyzed to reveal its genomic potential. The oil degradation and growth conditions including nitrogen, and phosphorus sources, degradation cycle, biological dosing, pH, and oil concentration were optimized to exploit its commercial application. The genome of the DH7 strain contains 4,705,032 bp with GC content of 54.95% and 4653 genes. The genome analysis revealed that there are several metabolic pathways and enzyme-encoding genes related to oil degradation in the DH7 genome, such as the paa gene cluster which is involved in the phenylacetic acid degradation pathway, and complete degradation pathways for fatty acid and benzoate, genes related to chlorinated alkanes and olefins degradation pathway including adhP, frmA, and adhE, etc. The strain DH7 under the optimized conditions has demonstrated a maximum degradation efficiency of 84.6% after 14 days of treatment using synthetic oil, which comparatively displays a higher oil degradation efficiency than any Enterobacter species known to date. To the best of our knowledge, this study presents the first-ever genomic studies related to the oil degradation potential of any Enterobacter species. As Enterobacter kobei DH7 has demonstrated significant oil degradation potential, it is one of the good candidates for application in the bioremediation of oil-contaminated environments.

Unveiling the draft genome sequence of diesel-degrading Paenibacillus sp. strain d9, a surfactant producer isolated from diesel-contaminated soil

Introduction: Gram-positive bacteria, particularly Bacillus and Paenibacillus spp., have gained significant attention for their potential in environmental bioremediation (biosurfactant production) and diverse biotechnological applications. Among these, Paenibacillus sp. D9, isolated from oil-contaminated soil, has shown diesel and engine oil degradation capabilities and biosurfactant production. However, its role in alkane degradation remains unexplored. Methodology and Result: To shed light on its unique attributes, we conducted whole-genome sequencing of Paenibacillus sp. D9 using the Illumina HiSeq 2000 platform. The draft genome comprised 56 contigs and 7 scaffolds, with a size of 5,645,302 bp at 157.94× coverage and a G + C content of 58.13%. A total of 9,950 Coding Sequences (CDSs) were predicted, and functional annotation revealed 3,283 (43.19%) and 3,155 (58.8%) putative genes based on Bacterial Annotation System (BASys) and Rapid Annotation using the Subsystems Technology (RAST) subsystem categorization, respectively. Furthermore, 93 tRNA and 23 rRNA genes were identified. Conclusion: This genome announcement provides valuable insights into the genetic potential of Paenibacillus sp. D9 and paves the way for future research in its biotechnological applications.

Phenotypically complex living materials containing engineered cyanobacteria

The field of engineered living materials lies at the intersection of materials science and synthetic biology with the aim of developing materials that can sense and respond to the environment. In this study, we use 3D printing to fabricate a cyanobacterial biocomposite material capable of producing multiple functional outputs in response to an external chemical stimulus and demonstrate the advantages of utilizing additive manufacturing techniques in controlling the shape of the fabricated photosynthetic material. As an initial proof-of-concept, a synthetic riboswitch is used to regulate the expression of a yellow fluorescent protein reporter in Synechococcus elongatus PCC 7942 within a hydrogel matrix. Subsequently, a strain of S. elongatus is engineered to produce an oxidative laccase enzyme; when printed within a hydrogel matrix the responsive biomaterial can decolorize a common textile dye pollutant, indigo carmine, potentially serving as a tool in environmental bioremediation. Finally, cells are engineered for inducible cell death to eliminate their presence once their activity is no longer required, which is an important function for biocontainment and minimizing environmental impact. By integrating genetically engineered stimuli-responsive cyanobacteria in volumetric 3D-printed designs, we demonstrate programmable photosynthetic biocomposite materials capable of producing functional outputs including, but not limited to, bioremediation.

Mechanistic insights into the response of electroactive biofilms to Cd2+ shock: bacterial viability and electron transfer behavior at the cellular and community levels

Electroactive biofilms (EABs) play a crucial role in environmental bioremediation due to their excellent extracellular electron transfer (EET) capabilities. However, Cd2+ can have toxic effects on the electrochemical performance of EABs, and the comprehensive inhibition mechanism of EABs in response to Cd2+ shock remains elusive. This study indicated that Cd2+ shock significantly reduced biomass and increased oxidative stress in EABs at the cellular level. The bacterial viability of EABs in phase III under 0.5 mM Cd2+ shock (EABCd2+-III0.5) decreased by 16.31% compared to EABCK-III. Moreover, intracellular NADH, c-Cyts, and the abundance of electroactive species were essential indicators to evaluate EET behavior of EABs. In EABCd2+-III0.5, these indicators decreased by 26.32%, 33.40%, and 20.65%, respectively. Structural equation modeling analysis established quantitative correlations between core components and electrochemical activity at cellular and community levels. The correlation analysis revealed that the growth and electron transfer functions of EABs were predictive indicators for their electrochemical performance, with standardized path coefficients of 0.407 and 0.358, respectively. These findings enhance our understanding of EABs’ response to Cd2+ shock and provide insights for improving their performance in heavy metal wastewater.

Pseudomonas aeruginosa based concurrent degradation of beta-cypermethrin and metabolite 3-phenoxybenzaldehyde, and its bioremediation efficacy in contaminated soils

Beta-cypermethrin is one of the widely used pyrethroid insecticides, and problems associated with the accumulation of its residues have aroused public attention. Thus, there is an urgent need to effectively remove the beta-cypermethrin that is present in the environment. Biodegradation is considered a cost-effective and environmentally friendly method for removing pesticide residues. However, the beta-cypermethrin-degrading microbes that are currently available are not optimal. In this study, Pseudomonas aeruginosa PAO1 was capable of efficiently degrading beta-cypermethrin and its major metabolite 3-phenoxybenzaldehyde in water/soil environments. Strain PAO1 could remove 91.4% of beta-cypermethrin (50 mg/L) in mineral salt medium within 120 h. At the same time, it also possesses a significant ability to metabolize 3-phenoxybenzaldehyde—a toxic intermediate of beta-cypermethrin. The Andrews equation showed that the maximum substrate utilization concentrations of beta-cypermethrin and 3-phenoxybenzaldehyde by PAO1 were 65.3558 and 49.6808 mg/L, respectively. Box–Behnken design-based response surface methodology revealed optimum conditions for the PAO1 strain-based degradation of beta-cypermethrin as temperature 30.6 °C, pH 7.7, and 0.2 g/L inoculum size. The results of soil remediation experiments showed that indigenous micro-organisms helped to promote the biodegradation of beta-cypermethrin in soil, and beta-cypermethrin half-life in non-sterilized soil was 6.84 days. The bacterium transformed beta-cypermethrin to produce five possible metabolites, including 3-phenoxybenzyl alcohol, methyl 2-(4-hydroxyphenoxy)benzoate, diisobutyl phthalate, 3,5-dimethoxyphenol, and 2,2-dimethyl-1-(4-phenoxyphenyl)propanone. Among them, methyl 2-(4-hydroxyphenoxy)benzoate and 3,5-dimethoxyphenol were first identified as the intermediate products during the beta-cypermethrin degradation. In addition, we propose a degradation pathway for beta-cypermethrin that is metabolized by strain PAO1. Beta-cypermethrin could be biotransformed firstly by hydrolysis of its carboxylester linkage, followed by cleavage of the diaryl bond and subsequent metabolism. Based on the above results, P. aeruginosa PAO1 could be a potent candidate for the beta-cypermethrin-contaminated environmental bioremediation.

Synthetic bacterial consortia enhanced the degradation of mixed priority phthalate ester pollutants

Dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), bis(2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DOP) are hazardous chemicals listed as priority pollutants that disrupt endocrine systems. According to available reports, these six priority phthalate esters (PAEs) are considered the most polluting; however, no studies have been conducted on the efficient remediation of these PAEs. We therefore designed and constructed a synthetic bacterial consortium capable of the simultaneous and efficient degradation of six priority PAEs in minimal inorganic salt medium (MSM) and soil. The consortium comprised Glutamicibacter sp. ZJUTW, which demonstrates priority for degrading short-chain PAEs; Cupriavidus sp. LH1, which degrades phthalic acid (PA) and protocatechuic acid (PCA), intermediates of the PAE biodegradation process; and Gordonia sp. GZ-YC7, which efficiently degrades long-chain priority PAEs, including DEHP and DOP. In MSM containing the six mixed PAEs (250 mg/L each), the ZJUTW + YC + LH1 consortium completely degraded the four short-chain PAEs within 48 h, and DEHP (100%) and DOP (62.5%) within 72 h. In soil containing the six mixed PAEs (DMP, DEP, BBP, and DOP, 400 mg/kg each; DBP and DEHP, 500 mg/kg, each), the ZJUTW + YC + LH1 consortium completely degraded DMP, DEP, BBP, and DBP within 6 days, and 70.84% of DEHP and 66.24% of DOP within 2 weeks. The consortium efficiently degraded the six mixed PAEs in both MSM and soil. We thus believe that this synthetic microbial consortium is a strong candidate for the bioremediation of environments contaminated with mixed PAE pollutants.

In vitro assays reveal inherently insecticide-tolerant termite symbionts.

Introduction: Termite symbionts are well known for conferring a myriad of benefits to their hosts. Bacterial symbionts are repeatedly associated with increased fitness, nutritional supplementation, pathogen protection, and proper development across insect taxa. In addition, several recent studies link bacterial symbionts to reduced insecticide efficacy. This has important implications both in pest control management and environmental bioremediation efforts. Insects' guts may be a valuable resource for microbes with broad application given their unique niches and metabolic diversity. Though insecticide resistance in termites is considered unlikely due to their life history, the close association of termites with a multitude of bacteria raises the question: is there potential for symbiont-mediated pesticide tolerance in termites? Methods and results: We identified a candidate that could grow in minimal medium containing formulated pesticide. This bacterial isolate was then subjected to continuous culture and subsequently demonstrated improved performance in the presence of pesticide. Isolates subjected to continuous culture were then grown at a range of concentrations from 1-10X the formulation rate. After constant exposure for several generations, isolates grew significantly better. Conclusion: Here we demonstrate that naïve insect hosts can harbor symbionts with inherent insecticide tolerance capable of rapid adaptation to increasing insecticide concentrations overtime. This has broad implications for both pest control and environmental cleanup of residual pesticides.

Compartmentation of trace metals in Cymodocea nodosa from a heavily polluted area (Central Gulf of Gabes; Southern Mediterranean Sea): Potential use of the seagrass as environmental monitoring and bioremediation tool

This study was conducted to better understand the adaptative strategies of Cymodocea nodosa occurring in the heavily polluted environment of central Gulf of Gabes (SE Tunisia). Cd, Cu, Pb and Zn concentrations were assessed in the seagrass roots, rhizomes, and leaves, and in the surrounding seawater and sediments. Sediments were found to be the main source of contaminants bioaccumulated in C. nodosa. Bioaccumulation patterns differed significantly with metals and plant organs. While Cd, Cu and Zn were found to accumulate in leaves, Pb concentrates mainly in roots. In the heavily polluted environment of the Gulf of Gabes, C. nodosa seems to have developed two different adaptative strategies: metal trapping in roots and metal transfer from permanent (roots) to temporary (leaves) organs. These mechanisms allow the seagrass to remove the excess of metals. These properties show the potential use of C. nodosa not only as bioindicator but also as an effective bioremediation tool.

Nanobioremediation: a potential and sustainable strategy to combat environmental pollution

Environment and human health are continuously threatened due to various pollutants that have emerged from multiple world events, such as industrial development and exponential population growth. As a result, finding and implementing new solutions to address the problem of environmental contamination has become critical. Nanotechnology is a new science that has applications in a variety of sectors including environmental bioremediation. Nanomaterials (NMs) possess distinctive physical and chemical properties, hence the attention of scientists and researchers associated with environment, especially bioremediation have been focused to them. Nanoremediation is a potential technique for dealing with persistent pollutants such as pesticides, halogenated chemicals, heavy metals, chlorinated solvents etc. It is also a long-term solution for developing contaminants removal of from soil, air, and water due to its adaptability. This article gives an outline of how different types of NMs can be used to deal with environmental health including status of soil, water, and air remediation using various NMs such as carbon, metal, silica, polymer etc.

Uncovering the metabolic pathway of novel Burkholderia sp. for efficient triclosan degradation and implication: Insight from exogenous bioaugmentation and toxicity pressure

Triclosan (TCS), a synthetic and broad-spectrum antimicrobial agent, is frequently detected in various environmental matrices. A novel TCS degrading bacterial strain, Burkholderia sp. L303, was isolated from local activated sludge. The strain could metabolically degrade TCS up to 8 mg/L, and optimal conditions for TCS degradation were at temperature of 35 °C, pH 7, and an increased inoculum size. During TCS degradation, several intermediates were identified, with the initial degradation occurring mainly through hydroxylation of aromatic ring, followed by dechlorination. Further intermediates such as 2-chlorohydroquinone, 4-chlorocatechol, and 4-chlorophenol were produced via ether bond fission and C–C bond cleavage, which could be further transformed into unchlorinated compounds, ultimately resulting in the complete stoichiometric free chloride release. Bioaugmentation of strain L303 in non-sterile river water demonstrated better degradation than in sterile water. Further exploration of the microbial communities provided insights into the composition and succession of the microbial communities under the TCS stress as well as during the TCS biodegradation process in real water samples, the key microorganisms involved in TCS biodegradation or showing resistance to the TCS toxicity, and the changes in microbial diversity related to exogenous bioaugmentation, TCS input, and TCS elimination. These findings shed light on the metabolic degradation pathway of TCS and highlight the significance of microbial communities in the bioremediation of TCS-contaminated environments.

Isolation and Screening of Microorganisms from Waste Dumping Sites for Biosorption of Cadmium and Lead

Heavy metal poisoning of the environment poses a serious threat to ecosystems and human health. Landfills have been found to harbor diverse microbial communities capable of bioremediating such contaminants via biosorption. Unlike traditional methods of heavy metal remediation, which often involve costly and resource-intensive techniques, biosorption offers a promising alternative that harnesses the natural capabilities of microorganisms. The objective of this research was to identify and screen microorganisms from landfills for their ability to bio-sorb cadmium (Cd) and lead (Pb). The present study deals with the isolation and screening of the microorganisms capable of removing heavy metals from the area near Dehradun Municipal Solid Waste Management Pvt. Ltd. Among the 17 bacterial isolates and 2 fungal isolates, only 7 bacteria and one fungal strain were able to absorb the heavy metal concentration. Among the 7 bacterial strains, the percentage of microbes with the ability to absorb Pb ranged from 35% to 70%, while the percentage of microbes with the ability to absorb Cd ranged from 20% to 50%. On the other hand, the fungal strain had an absorption capacity of about 80% for both Pb and Cd. This study emphasizes the potential of microorganisms isolated from landfills as attractive candidates for Cd and Pb biosorption. These isolates show significant tolerance and efficient biosorption capacities, making them good candidates for further exploration and prospective application in the bioremediation of heavy metal-contaminated environments.