Search Results (216)

Heavy metal pollution, particularly copper contamination, threatens the ecological environment and human survival. In response to this pressing environmental issue, the development of innovative remediation strategies has become imperative. Bioremediation technology is characterized by remarkable advantages, including its ecological friendliness, cost-effectiveness, and operational efficiency. In our previous research, Rossellomorea sp. ZC255 demonstrated substantial potential for environmental bioremediation applications. This study investigated the removal characteristics and underlying mechanism of strain ZC255 and revealed that the maximum removal capacity was 253.4 mg/g biomass under the optimal conditions (pH 7.0, 28 °C, and 2% inoculum). The assessment of the biosorption process followed pseudo-second-order kinetics, while the adsorption isotherm may fit well with both the Langmuir and Freundlich models. Cell surface alterations on the Cu(II)-treated biomass were observed through scanning electron microscopy (SEM). Cu(II) binding functional groups were determined via Fourier transform infrared spectroscopy (FTIR) analysis. Simultaneously, the genomic analysis of strain ZC255 identified multiple genes potentially involved in heavy metal resistance, transport, and metabolic processes. These studies highlight the significance of strain ZC255 in the context of environmental heavy metal bioremediation research and provide a basis for using strain ZC255 as a copper removal biosorbent. Full article

Widespread antibiotic residues are accumulating in the environment, potentially causing adverse effects for humans, animals, and the ecosystem, including an increase in antibiotic-resistant bacteria, resulting in worldwide concern. There are various commonly used physical, chemical, and biological treatments for the degradation of antibiotics. However, the elimination of toxic end products generated by physicochemical methods and the need for industrial applications pose significant challenges. Hence, environmentally sustainable, green, and readily available approaches for the transformation and degradation of these antibiotic compounds are being sought. Herein, we review the impact of sustainable fungal laccase-based bioremediation strategies. Fungal laccase enzyme is considered one of the most active enzymes for biotransformation and biodegradation of antibiotic residue in vitro. For industrial applications, the low laccase yields in natural and genetically modified hosts may constitute a bottleneck. Methods to screen for high-laccase-producing sources, optimizing cultivation conditions, and identifying key genes and metabolites involved in extracellular laccase activity are reviewed. These include advanced transcriptomics, proteomics, and metagenomics technologies, as well as diverse laccase-immobilization technologies with different inert carrier/support materials improving enzyme performance whilst shifting from experimental assays to in situ monitoring of residual toxicity. Still, more basic and applied research on laccase-mediated bioremediation of pharmaceuticals, especially antibiotics that are recalcitrant and prevalent, is needed. Full article

Microcystins (MCs) are the most toxic and abundant cyanotoxins found in natural waters during harmful cyanobacterial blooms. These toxins pose a significant threat to plant, animal, and human health due to their toxicity. Degradation of MCs by MC-degrading bacteria is a promising method for controlling these toxins, demonstrating safety, high efficiency, and cost-effectiveness. In this study, we isolated potential MC-degrading bacteria (strains TA13, TA14, and TA19) from Lake Kasumigaura in Japan and found that they possess a high capacity for MC degradation. Based on 16S rRNA gene sequencing, all three isolated strains were identified as belonging to the Klebsiella species. These bacteria effectively degraded MC-RR, MC-YR, and MC-LR under various temperature and pH conditions within 10 h, with the highest degrading activity and degradation rate observed at 40 °C. Furthermore, the isolated strains efficiently degraded MCs not only under neutral pH conditions, but also in alkaline environments. Additionally, we detected the MC-degrading gene (mlrA) in all three isolated strains, marking the first report of the mlrA gene in Klebsiella species. The copy number of the mlrA gene in the strains increased after exposure to MCs. These findings indicate that strains TA13, TA14, and TA19 significantly contribute of MC bioremediation in Lake Kasumigaura during cyanobacterial blooms. Full article

Torrefaction is a thermochemical pretreatment in which biomass is heated at 200–300 °C for 30–60 min in an inert atmosphere. Torrefaction has been previously used to improve the fuel properties of lignocellulosic biomass; however, the use of torrefaction for bioenergy generation represents a low-value final product as well as the dead end of the biomass value chain. Herein, we demonstrate the proof-of-concept for the utilisation of torrefaction as a pretreatment to convert low-value wood waste into biosurfactants, a high-value specialty biochemical. Wood waste was torrefied at 225 °C, 250 °C, 275 °C, and 300 °C and physicochemically characterised using proximate and ultimate analyses, FTIR, XRD, TGA–DTG, and SEM–EDX to assess its suitability as fermentation feedstock. Aspen waste torrefied at temperatures less than 250 °C was directly utilised by Burkholderia thailandensis DSM 13276 via semi-solid-state fermentation to yield biosurfactants, and 225 °C was selected for further experiments as it resulted in the production of biosurfactants which reduced the surface tension of the production medium to 36.8 mN/m and had an emulsification index of 64.1%. Tension and emulsification activities decreased with the increase in torrefaction temperature. The biosurfactant derived from torrefaction at 225 °C formed highly stable emulsions with diesel oil (lasting >40 days), in addition to low interfacial tension, suggesting potential applications in diesel bioremediation. This integrated, chemical-free strategy offers an alternative application for torrefied wood waste as well as a feasible solution for the cost-effective chemical-free production of biosurfactants, incorporating circular economy principles. Full article

The escalating climate crisis and the imperative to transition from a fossil fuel-dependent economy demand transformative solutions for sustainable energy and carbon management. Biological CO₂ capture and utilization (CCU) using microalgae represents a particularly compelling approach, capitalizing on microalgae’s high photosynthetic efficiency and remarkable product versatility. This review critically examines the principles and recent breakthroughs in microalgal CO₂ bioconversion, spanning strain selection, advanced photobioreactor (PBR) design, and key factors influencing carbon sequestration efficiency. We explore diverse valorization strategies, including next-generation biofuel production, integrated wastewater bioremediation, and the synthesis of value-added chemicals, underscoring their collective potential for mitigating CO₂ emissions and achieving comprehensive resource valorization. Persistent challenges, such as economically viable biomass harvesting, cost-effective scale-up, and enhancing strain robustness, are rigorously examined. Furthermore, we delineate promising future prospects centered on cutting-edge genetic engineering, integrated biorefinery concepts, and synergistic coupling with waste treatment to maximize sustainability. By effectively bridging carbon neutrality with renewable resource production, microalgae-based technologies hold considerable potential to spearhead the circular bioeconomy, accelerate the renewable energy transition, and contribute significantly to achieving global climate objectives. Full article

The release of polycyclic aromatic hydrocarbons (PAHs) into the environment has become a serious concern with rapidly increasing human activities. PAHs are one of the hazardous pollutants generated primarily from the incomplete combustion of fossil fuels, industrial emissions, and the expenditure of vehicles. These toxic compounds are very dangerous to ecosystems and human health due to being persistent, bioaccumulative, and carcinogenic. Composting is considered a form of bioremediation for eliminating PAHs in contaminated soils. The method utilizes microbial communities to break down organic pollutants and is low-cost and environmentally friendly. The efficiency factor depends on many aspects, including soil pH, oxygen, temperature provision, and the diversity of microbes, among others. Thermophilic conditions help in the decomposition of both low- and high-molecular-weight PAHs. This paper focuses on the effectiveness of composting as a bioremediation technology for remediating PAH-contaminated soils and its impact on the environment and human health. Due to its safety and high efficiency, composting should be improved and prioritized for its widespread application as a principal remediation technology for PAH pollution at the earliest opportunity. Full article

Microalgae are increasingly recognised as sustainable, nutrient-dense sources of bioactive compounds with broad health-promoting potential. Rich in carotenoids, phenolics, polyunsaturated fatty acids, phycobiliproteins, sterols, and essential vitamins, microalgae offer a promising foundation for functional foods targeting chronic disease prevention. This narrative review explores the nutritional profiles and biological effects of key species, including Spirulina (Limnospira platensis), Chlorella, Haematococcus, and Nannochloropsis. Scientific evidence supports their antioxidant, anti-inflammatory, immunomodulatory, antimicrobial, and metabolic regulatory activities, contributing to reduced risks of cardiovascular, metabolic, inflammatory, and neurodegenerative disorders. Special emphasis is placed on the synergistic benefits of consuming whole biomass compared to isolated compounds and the technological strategies, such as encapsulation, cell wall disruption, and nutrient optimisation, that enhance the bioavailability of microalgal bioactives. Furthermore, the environmental advantages of microalgae cultivation, such as minimal land and freshwater requirements, carbon sequestration, and wastewater bioremediation, highlight their role in the transition toward sustainable food systems. Despite challenges related to high production costs, sensory attributes, scalability, and regulatory approval, advances in biotechnology, processing, and formulation are paving the way for their broader application. Overall, microalgae represent next-generation bioactive sources that promote human health and environmental sustainability, positioning them as key players in future functional foods and nutraceuticals. Full article

The increasing global oil consumption has led to significant soil contamination by hydrocarbons, notably diesel-range hydrocarbons. Soil bioremediation through bacterial bioaugmentation is an alternative to increase the degradation of organic pollutants such as petroleum products. Bioremediation is a sustainable practice that contributes to the Sustainable Development Goals (SDGs) because it is environmentally friendly, reduces the impact of human activities, and avoids the use of invasive and destructive methods in soil restoration. This study examines the bioremediation potential of hydrocarbonoclastic bacteria isolated from soil close to areas with a risk of spills due to pipelines carrying hydrocarbons. Among the isolated strains, Arthrobacter globiformis, Pantoea agglomerans, and Nitratireductor soli exhibited hydrocarbonoclast activity, achieving diesel removal of up to 90% in short-chain alkanes and up to 60% in long-chain hydrocarbons. The results from in silico studies, which included molecular docking and molecular dynamics simulations, suggest that the diesel removal activity can be explained by the bioavailability of the linear alkanes and their affinity for alkane monooxygenase AlkB present in the studied microorganisms, since long-chain hydrocarbons had lower enzyme affinity and lower aqueous solubility. The correlation of the experimental results with the computational analysis allows for greater insight into the processes involved in the microbial degradation of hydrocarbons with varying chain lengths. Furthermore, this methodology establishes a cost-effective approximation tool for the evaluation of the feasibility of using different microorganisms in bioremediation processes. Full article

Researchers have identified mercury as one of the most toxic environmental pollutants, with deleterious effects on human health and biota. Microorganisms play a key role in the accumulation, degradation, and neutralisation of mercury. Numerous bacteria, fungi, and microalgae possess the mer operon and its homologues, which contain genes responsible for the transport and detoxification of mercury compounds. Mercury-tolerant Microorganisms efficiently convert mercury into less toxic forms. Their tolerance characteristics position them as promising agents for the remediation of ecosystems altered by human activity. This review explores the mechanisms by which microorganisms resist mercury and their potential for biotechnological applications, including eco-friendly and cost-effective bioremediation of mercury-contaminated environments. Full article

Enzymes, as nature’s precision biocatalysts, hold transformative potential across industrial, environmental, and biomedical sectors. However, their instability, solvent sensitivity, and limited reusability in their free form necessitate advanced immobilization strategies to enhance their robustness and scalability. This review critically examines cutting-edge advancements in enzyme immobilization, focusing on the integration of artificial intelligence (AI), novel nanomaterials, and dynamic carrier systems to overcome the traditional limitations of mass transfer, enzyme leakage, and cost inefficiency. Key innovations such as metal–organic frameworks (MOFs), magnetic nanoparticles, self-healing hydrogels, and 3D-printed scaffolds are highlighted for their ability to optimize enzyme orientation, stability, and catalytic efficiency under extreme conditions. Moreover, AI-driven predictive modeling and machine learning emerge as pivotal tools for rationalizing nanomaterial synthesis, multi-enzyme cascade design, and toxicity assessment, while microfluidic systems enable precise biocatalyst fabrication. This review also explores emerging carrier-free strategies, including cross-linked enzyme aggregates (CLEAs) and DNA-directed immobilization, which minimize diffusion barriers and enhance substrate affinity. Despite progress, challenges persist in regards to eco-friendly nanomaterial production, industrial scalability, and real-world application viability. Future directions emphasize sustainable hybrid material design, AI-aided lifecycle assessments, and interdisciplinary synergies between synthetic biology, nanotechnology, and data analytics. By connecting laboratory innovation with industrial needs, this work provides a forward-thinking framework to harness immobilized enzymes for achieving global sustainability goals, particularly in bioremediation, bioenergy, and precision medicine. Full article

Proteins are crucial for medicine, pharmaceuticals, food, and environmental applications since they are used in various fields such as synthesis of drugs, industrial enzyme production, biodegradable plastics, bioremediation processes, etc. Xylanase is an important and versatile enzyme with applications across various industries, including pulp and paper, biofuel production, food processing, textiles, laundry detergents, and animal feed. Key parameters in biotechnological protein production include temperature, pH, and working volumes and especially medium compositions where optimization is crucial for large-scale applications due to cost considerations. Machine learning methods have emerged as effective alternatives to traditional statistical approaches in optimization. This study focuses on optimizing xylanase production via bioprocesses by employing regression analysis on datasets from various studies. The extreme gradient boosting (XGBoost) regression model was applied to predict xylanase activity under different experimental conditions, accurately predicting xylanase activity and identifying the significance of each variable. This study utilized experimentally derived datasets from peer-reviewed publications, in which the corresponding laboratory experiments had already been conducted and validated. The results demonstrate that machine learning methods can effectively optimize protein production processes, offering a strong alternative to traditional statistical approaches. Full article

Manganese peroxidase (MnP) is widely studied for its potential in bioremediation, although its production typically relies on costly synthetic culture media (SCM). This study evaluates olive mill solid waste (OMSW) as a sustainable substrate for MnP production. Three alternatives were evaluated: (1) using SCM; (2) using OMSW; and (3) using OMSW, followed by anaerobic digestion (AD). The alternatives were evaluated by both an economic and life cycle assessment (LCA). The economic analysis considered indicators such as net present value (NPV), internal rate of return (IRR), and payback period. The LCA methodology was conducted according to ISO 14040/44 standards, with a cradle-to-gate system boundary, using SimaPro v9.4 software. Replacing SCM with OMSW improved economic performance, though environmental impacts showed no significant improvement and, in some cases, worsened. In contrast, combining OMSW with anaerobic digestion enhanced both dimensions: Alternative 3 reached the highest NPV (USD 984,464), a 20.9% IRR, and a 4.1-year payback, while reducing impacts by 275% (Stratospheric ozone depletion), 89% (terrestrial ecotoxicity), 78% (freshwater ecotoxicity), and 50% (marine eutrophication) compared to Alternative 1. Finally, the use of OMSW combined with AD reduces economic costs and environmental impact, contributing to the field of sustainable enzyme production Full article

The biodegradation of glyphosate by bacteria is an emerging bioremediation strategy necessitated by the intensive use of this herbicide in global agriculture. This study systematically reviews the literature to identify bacteria with the potential to degrade glyphosate. The PRISMA protocol was utilized, considering relevant articles identified in electronic databases such as PubMed, Scopus, and Science Direct. The research identified 34 eligible studies, highlighting the genera Bacillus, Pseudomonas, and Ochrobactrum as having the greatest potential for glyphosate degradation. These findings were based on analytical techniques such as High-Performance Liquid Chromatography (HPLC) and Nuclear Magnetic Resonance (NMR), which identified and quantified intermediate metabolites, primarily AMPA (aminomethylphosphonic acid), sarcosine, and glyoxylate. This investigation also addressed enzymatic efficiency in biodegradation, emphasizing enzymes like glyphosate oxidoreductase and C-P lyases. The results indicated that South and North America lead in publications on this topic, with Argentina and the United States being the main contributors, reflecting the intense use of glyphosate in these countries. Additionally, studies in Europe and Asia focused on microbial diversity, exploring various bacterial genera. This investigation revealed that despite the promising microbial potential, there are challenges related to environmental condition variations and the cost of large-scale implementation, indicating that continuous research and process optimization are essential for the effective and sustainable application of this biotechnology. Full article

Large-scale cultivation of cyanobacteria is often limited by the high cost of synthetic culture medium and the environmental impact of nutrient consumption. Cheese whey, a major agro-industrial waste product, is rich in organic and inorganic nutrients, making it a promising low-cost alternative for microbial growth while addressing waste bioremediation. This study investigates the growth performance and the biochemical composition of four different cyanobacterial species (Phormidium sp., Synechocystis sp., Chlorogloeopsis fritschii, and Arthrospira platensis), cultivated in cheese whey (CW). Pretreated CW was used at 20% and 100% v/v concentrations. All species grew satisfactorily in both concentrations, reaching biomass above 4 g L⁻¹ (in 100% v/v CW) and 2 g L⁻¹ (in 20% v/v CW). The highest μ_max value (0.28 ± 0.02 d⁻¹) was presented by Synechocystis sp. grown in 20% CW. Waste bioremediation of both 20 and 100% v/v CW demonstrated effective nutrient removal, with COD removal exceeding 50% for most species, while total nitrogen (TN) and total phosphorus (TP) removals reached up to 33% and 32%, respectively. Biochemical composition analysis revealed high carbohydrate and protein content, while lipid content remained below 15% in all cases. Interestingly, C. fritschii accumulated 11% w/w polyhydroxyalkanoates (PHAs) during the last day of cultivation in 20% v/v CW. These findings highlight the potential of C. fritschii as a valuable candidate for integration into bioprocesses aimed at sustainable bioplastic production. Its ability to synthesize PHAs from agro-industrial waste not only enhances the economic viability of the process but also aligns with circular economy principles. This study is a primary step towards establishing a biorefinery concept for the cultivation of cyanobacterial species in cheese whey-based wastewater streams. Full article

The valorization of dredged sediments (DS) presents a sustainable solution for managing waste while addressing resource scarcity and environmental concerns. This review explores treatment techniques and reuse options for DS, focusing on applications in the construction industry. However, disposal poses challenges due to potential contamination with heavy metals and organic pollutants. The study categorizes treatment approaches into physical, chemical, biological, and thermal processes. Physical methods, such as separation and dewatering, offer volume reduction but have limited capacities against chemically bound contaminants. Chemical treatments, including oxidation and immobilization, target specific pollutants but often entail high costs and environmental risks. Biological approaches, such as bioremediation and phytoremediation, provide sustainable, low-cost alternatives but require longer timescales. Thermal processes like pyrolysis and vitrification efficiently destroy or stabilize contaminants but involve high energy demands. Pyrolysis emerges as a particularly promising technology, combining effective decontamination with energy recovery and biochar production. Despite the advances in the area, the review identifies key barriers to large-scale DS reuse: contamination variability, lack of standardized guidelines, and limited long-term performance data. Future research should focus on integrated treatment strategies, such as combining DS with other industrial by-products, and optimization of processing, aiming to attain cost-effective, sustainable reuse. Overall, the valorization of treated DS supports circular-economy principles and offers significant environmental and economic benefits. Full article