Biodegradation最新文献

Pharmaceutical pollutants have emerged as pervasive environmental contaminants, entering ecosystems via wastewater effluents, agricultural runoff and improper disposal. These pollutants typically belong to classes such as antiepileptics, antibiotics, analgesics, non-steroidal anti-inflammatory drugs, hormones and antiseptics. Their recalcitrance arises from their stable chemical structures, which resist degradation and pose significant challenges for conventional wastewater treatment processes, leading to their persistence in the environment and potentially harmful effects on ecosystems and human health. This study investigates microbial engineering strategies for the efficient degradation of pharmaceutical pollutants. Recent advancements in CRISPR systems, ALE, metabolic engineering, bioaugmentation and bioreactor designs have significantly improved pollutant breakdown. Additionally, novel approaches to address emerging contaminants and the application of advanced biotechnologies like synthetic biology and metagenomics are crucial for developing more effective and sustainable bioremediation strategies. These insights offer a roadmap for developing more effective and sustainable solutions for the bioremediation of pharmaceutical pollutants.

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Microbial enhanced oil recovery (MEOR) is an innovative method for recovering residual oil from aged oil wells but availability of indigenous microorganisms in the reservoir with high potential for MEOR and biodegradation has always been a challenge. Samples from aged oil wells were analysed using 16S rRNA ribotyping, and other microbial activity tests which include hydrocarbon degradation, sulphate reduction, nitrate reduction, acetate utilization and methane production. Hydrocarbon degradation dominated activities in all samples and sequenced data implicated the genus Pseudomonas, to be present in all the oil wells and dominating in OKP-7T (98%), OVH-12T (54%), SAP-12L (94%), OBN-15L (71%), ORO-6T (66%) and OKP-5S (86%). The corresponding data on anaerobic biodegradation of oil well samples when supplemented with acetate commonly found in samples showed same samples dominated by the genus Pseudomonas also degrading between 51 and 87% of the residual hydrocarbons in samples after 10 weeks of anaerobic incubation. Other microbial activities observed in the study were nitrate reduction where the genus Tepidiphilus, were found in four samples (OVH-1S, OVH-3L, OVH-12T and SAP-9S) and dominating in OVH-1S (74%). Some samples also showed methanogenic activities as evidenced by the occurrence of Methanobravibacter and Methanothermoacter in the sequenced data. Dominance of the oil wells by the genus Pseudomonas with high potential for biodegradation and MEOR will be of great significance to the oil industry especially when considering aged oil wells that have approached their economic limits. This study was the first to investigate the dominance of the genus Pseudomonas in low sulphate aged oil wells in the Niger Delta and the potential prospects of such dominance for biodegradation and MEOR applications.

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Plastic pollution is a worldwide problem, especially when it comes to polyethylene (PE), the most consumed plastic in the world. Biodegradation is a naturally occurring process mediated by microorganisms and their enzymes. The biodegradation of PE by fungi has been investigated since 1980, and these microorganisms are considered great PE biodegraders due to the strong oxidative activity and low substrate specificity of their ligninolytic extracellular enzymes. This review covers 40 manuscripts published up to December 31st of 2024 and the search was performed on PudMed and Science Direct databases using keywords linked by Boolean operators. It was listed 26 cultivable fungal genera capable of biodegrading PE, of which Aspergillus was the genus most reported. Filamentous fungal species, mainly from terrestrial ecosystem were the most studied for this purpose; however, the highest PE biodegradation rates were demonstrated by fungi isolated from the aquatic environment (Alternaria alternata). The data evidences that different methods of plastic pre-treatment and fungal consortia improve and accelerate PE biodegradation. Moreover, there is a non-homogeneous global distribution of research in this area of knowledge as well as the need for a standardization of methodological experimentation. Therefore, this area of research is still in its infancy and deserves to be explored in more in-depth studies to advance biotechnological solutions for plastic waste management.

Polycyclic aromatic hydrocarbons (PAHs) such as anthracene persist in the ecosystem due to their low solubility, toxicity, and resistance to microbial attack, posing serious environmental and health risks. Current remediation approaches are often limited by poor degradation efficiency and incomplete mineralization. Here, we present a nano bioremediation strategy that couples Zinc Selenium (ZnSe) nanoparticles with biosurfactant-assisted microbial degradation to enhance anthracene removal. In this study, enrichment culture technique was performed to isolate potential strains, and it was identified as Dyadobacter endophyticus KSKT01 (accession number-PP422395) and Pseudomonas otitidis KKT09 (accession number-PP563796). The biosurfactants were isolated and characterized using FTIR and GC–MS, and it was identified as lipopeptides. The nanoparticles were synthesized and structurally characterized by a UV–Visible spectrophotometer, FTIR, FE-SEM, HR-TEM, EDX, AFM, and XRD. ZnSe exhibited an absorbance peak at 200 nm in the UV spectrum. The FTIR spectra showed possible functional groups associated with biomolecules (alkyne, alkene, and nitro compounds), FE-SEM and HR-TEM demonstrated that ZnSe nanoparticles were spherical in shape with a size range of 200 nm, and AFM also expressed a spherical form of the synthesized ZnSe NPs. XRD showed a crystalline size of 55.5 nm, and the element composition of ZnSe (Zn-53.2% and Se-46.8%) was analyzed by EDX. The obtained results expressed that ZnSe is stable and crystalline, which facilitated electron transfer and microbial interaction. Comparative degradation assays revealed that the combined nanoparticle, biosurfactant, and microbial consortium achieved 98% anthracene degradation in 14 days (50 mg/L). The Gas chromatography mass spectroscopy analysis confirmed the transformation of anthracene into less toxic intermediates such as naphthoic acid and salicylic acid via dioxygenase-mediated pathways. Our findings establish nanobioremediation as a promising platform for sustainable cleanup and provide mechanistic insight for anthracene degradation.

Plastic pollution has become one of the most pressing environmental issues worldwide, with large amounts of conventional plastics accumulating in terrestrial and marine ecosystems due to their persistence and ineffective waste management. Developing and understanding the biodegradation behavior of environmentally friendly alternatives, such as bioplastics, is therefore crucial to mitigate this problem. In this context, the degradation of PHBV-based biocomposites containing purified cellulose (TC), wood flour (WF), and almond shell (AS) fibers have been investigated and compared with neat PHBV in two Mediterranean marine locations—a port and the open sea, within the same geographic region. Changes in weight, surface morphology, surface roughness, surface chemistry, and mechanical properties were monitored and periodically evaluated over 18 months of seawater exposure at the two sites. After 18 months of immersion, PHBV/AS showed the highest disintegration degree (88% for 150 µm films and 33% for 500 µm sheets), with the port environment promoting up to a two- to three-fold higher biodegradation rate compared to the open sea. Additionally, mineralization was studied in lab-simulated marine conditions by tracking CO₂ release in order to study the actual effect of the fibers on the biodegradation rate of the PHBV. The research highlighted the significant influence of habitat-specific factors on biodegradation, with the port environment exhibiting a more pronounced impact on bacterial adhesion, weight loss, and the deterioration of mechanical properties compared to the open sea. Lignocellulosic fillers, regardless of type, promoted PHBV biodegradation in both conditions. In particular, PHBV/AS exhibited the highest disintegration degree, followed by PHBV/TC and PHBV/WF. Fiber characteristics such as size, shape, and porosity predominantly governed biocomposite disintegrability. Almond shell was revealed as the most favorable fiber for PHBV biodegradation during mineralization test. Under laboratory-simulated marine conditions, the composites reached 50% mineralization between 55 and 70% faster than neat PHBV, confirming the accelerating effect of the fibers on the biodegradation kinetics. This study aims to shed light on the understanding of the biodegradation mechanism of biodegradable polymers and the effect of cellulosic fillers on this natural process. Additionally, the study includes tests and measurements of biodegradation under real conditions, which will provide further insights into the kinetics of this process. This knowledge is of interest for designing biodegradable products and predicting their biodegradation time.

Crude oil pollution in soil poses a serious global risk to food production and ecosystem health. Polycyclic aromatic hydrocarbons (PAHs) are toxic organic compounds found in crude oil and pose health and ecosystem risks. In this study, we assessed the efficiency of indigenous Syrian fungal and bacterial isolates to biodegrade PAHs. To evaluate bioremediation potential, eighteen isolates were isolated, identified, and tested against 28 detected PAHs. The fungal isolates Aspergillus niger, Penicillium sp., and Cladosporium sp. exhibited chromatic change rates (CCR) of 82.2%, 87.3%, and 89.0%, respectively, and their combinations reached CCR of 93.7 ± 1.8%. Key bacterial isolates, including Pseudomonas sp., Bacillus sp., and Micrococcus sp., demonstrated effectiveness ranging from 77.3 to 78% individually, and 90.7% for consortium. Gas chromatography-mass spectrometry (GC–MS) analysis confirmed substantial reductions in crude oil components after biodegradation. These results demonstrated the value of indigenous microbes for bioremediation. This study is the first combined bacterial–fungal study of PAHs biodegradation in Syria, supporting the use of local isolates to enhance food security and environmental health. This would help decision makers to think about using eco-friendly strategies for PAHs remediation.

Wastewater treatment remains a global challenge, and not all conventional methods are successful from the perspective of sustainability and cost-effectiveness. Bioremediation, which leverages the metabolic activities of microorganisms, plants, and biological agents to degrade or neutralize pollutants, is increasingly recognized as a promising and sustainable remediation strategy. This review discusses the processes of bioremediation, including microbial degradation, bioaccumulation, and phytoremediation, and highlights their applications to various wastewater pollutants such as heavy metals, organic compounds, and nutrients. Special emphasis is placed on recent advancements such as genetically engineered microorganisms, nanotechnology-based enhancements, and integrated biological systems. By consolidating these developments, the review demonstrates the significance of bioremediation as a sustainable, cost-effective, and environmentally safe alternative to traditional wastewater treatment methods. It provides a comprehensive overview of recent advancements, technological innovations, and future opportunities that can assist researchers and practitioners in developing more efficient remediation systems. Finally, the review outlines emerging research directions needed to position bioremediation as a reliable and sustainable component of future wastewater treatment methods.

Aquaculture wastewater contains elevated levels of nutrients and organic pollutants that can accelerate eutrophication and impair aquatic ecosystems if discharged untreated. In the study, a fungal-based remediation approach was investigated for the removal of pollutants from aquaculture wastewater collected from Baltim Station ponds (31.55244° N, 31.092855° E) near Lake Burullus, Egypt. Two native fungal isolates, Aspergillus niger and Aspergillus flavus, were employed for primary mycoremediation experiments, while Ganoderma mbrekobenum was included only in the Plackett–Burman experimental design to evaluate the influence of environmental and nutritional factors on total phosphorus (TP) removal under optimized conditions. The fungal treatment significantly improved water quality, showing substantial reductions in total protein, phosphorus, nitrogen, organic matter, and chemical oxygen demand (COD) indicating a vital role of Aspergillus species in the bioremediation of nutrient-rich aquatic environments. The Plackett–Burman design (PBD) showed that fungal treatment significantly reduced pollutant concentrations with higher metabolic activity and enzymatic production as dehydrogenase and total protein from 9 to 12 days. Moreover, PBD identified KH₂PO₄ and MgSO₄ as the most influential variables for enhancing TP removal in the presence of G. mbrekobenum, while peptone and yeast extract exhibited the greatest effect in the non-fungal control system. The regression models demonstrated strong predictive accuracy (R² > 0.99), confirming the validity of the optimization approach. The results highlight the effectiveness of fungal biomass as a cost-effective and eco-friendly bioremediation strategy for mitigating nutrient pollution in aquaculture effluents and protecting sensitive aquatic environments such as Lake Burullus.

Polytetrafluoroethylene (PTFE) is a widely used fluoropolymer known for its chemical stability and resistance to degradation, making it a persistent environmental pollutant. The bioremediation of PTFE has proven challenging due to its inert nature. The aim of the present study is to characterize how changes in PTFE and irradiated PTFE may affect the proteomic profile of Aspergillus niger to propose protein biomarkers and depict bioremoval strategies. The results show that irradiating PTFE causes structural and spectral changes that increase with the increase of electron beam irradiation doses at 20, 40, 80, 160, and 320 kGy as compared to the control. PTFE and irradiated PTFE were added to a 24 h Aspergillus niger culture, and the proteomic profile was studied using quantitative protein assay and a high-throughput Ultra Performance Liquid Chromatography (UPLC) proteomics approach. The resultant chromatograms show that peak shifts can serve as a rapid indicator of PTFE and irradiated PTFE, highlighting the potential of proteomic profiling as a rapid screening tool. Energy Dispersive X-Ray (EDX) mapping images show fluoride attached to A. niger mycelia, while quanitative SPADNS Fluoride assay revealed deflourination % of 28.0 and 31.6% for 80 and 320 kGy irradiated PTFE culture, respectively, as compared 11.2% for non-irradiated PTFE. These findings suggest that 1) high electron beam irradiation doses enhance PTFE degradation, 2) the proteomic profile can be used as a biomarker to detect the presence of PTFE or irradiated PTFE, and 3) A. niger can be further exploited for both PTFE and irradiated PTFE bioremoval via deflourination or adsorption on mycelial network. Further research is needed to enhance the deflourination process.

Worldwide, one third of waste accumulation was shared by solid waste plastic bags which play a major role in manufacturing and packaging industries. Mismanage of waste plastics results in soil absorption and leads to soil infertility and structural degradation of soil. Biodegradation of plastic films enlighten the microbial activity towards plastic treatment without harming the ecosystem. Advancement towards biodegradation with aid of nanoparticles as degradation enhancer provides a synergistic approach to mitigate the plastic pollution. In this study, plastic degrading microorganisms were isolated from agriculture soil and metal nanoparticles such as Zinc oxide (ZnO) and Zinc-Magnesium oxide (ZnO-MgO) nanoparticles were synthesized using Co-precipitation method. Thus prepared inorganic metal nanoparticles were subsequently added to enhance the microbial degradation action. The synthesised nanoparticles appeared as hexagonal nanoflakes with a size range of 32.8 and 35 nm respectively. The isolated strain from the soil Stutzerimonas stutzeri, a gram negative bacterium was identified using 16S rRNA sequencing technique. The plastic films treated with isolated strain, showed 65% of degradation efficiency rate in the presence of synthesised nanoparticles as enhancers. SEM analysis confirmed the bacterial adhesion and revealed significant structural damage such as cracks, pits, holes and erosion in plastic film. FT-IR analysis revealed the presence of functional groups such as carbonyl (C=O) and (–CH) stretching at 1076 cm⁻¹ and 719 cm⁻¹ as a indication of polymer degradation. Further, simpler metabolic by-products formation such as fatty acids and succinic acid were analyzed using Gas Chromatography-Mass Spectrometry (GC–MS). Further, metabolic byproducts were analyzed using gas chromatography-mass spectrometry (GC–MS) and their toxicity was assessed using the Allium cepa as an invitro plant model. The absence of negative effects on mitotic cell division suggested that no toxic compounds were released during the microbial degradation process. This study reveals about an improved method of nanoparticles assisted biodegradation which may pave a better pathway for sustainable solution in plastic waste management.