Search Results (63)

The contamination of drinking water sources with selenium (Se) oxyanions, including selenite (Se(IV)) and selenate (Se(VI)), contains serious health hazards with an oral intake exceeding 400 µg/day and therefore requires urgent attention. Various natural and anthropogenic sources are responsible for high Se concentrations in aquatic environments. In addition, the chemical behavior and speciation of selenium can vary noticeably depending on the origin of the source water. The Se(VI) oxyanion is more soluble and therefore more abundant in surface water. Se levels in contaminated waters often exceed 50 µg/L and may reach several hundred µg/L, well above drinking water limits set by the World Health Organization (40 µg/L) and Germany (10 µg/L), as well as typical industrial discharge limits (5–10 µg/L). Overall, Se is difficult to remove using conventionally available physical, chemical, and biological treatment technologies. The recent literature has therefore highlighted promising advancements in Se removal using emerging technologies. These include advanced physical separation methods such as membrane-based treatment systems and engineered nanomaterials for selective Se decontamination. Additionally, other integrated approaches incorporating photocatalysis coupled adsorption processes, and bio-electrochemical systems have also demonstrated high efficiency in redox transformation and capturing of Se from contaminated water bodies. These innovative strategies may offer enhanced selectivity, removal, and recovery potential for Se-containing species. Here, a current review outlines the sources, distribution, and chemical behavior of Se in natural waters, along with its toxicity and associated health risks. It also provides a broad and multi-perspective assessment of conventional as well as emerging physical, chemical, and biological approaches for Se removal and/or recovery with further prospects for integrated and sustainable strategies. Full article

The need for sustainable and efficient water decontamination methods has led to the increasing use of redox enzymes such as glucose oxidase (GOx). GOx immobilization on textile supports provides a promising alternative for catalyzing pollutant degradation in bio-Fenton (BF) and bio-electro-Fenton (BEF) systems. However, challenges related to enzyme stability, reusability, and environmental impact remain a concern. This communication paper outlines innovative strategies developed to address these challenges, notably the use of ecotechnologies to achieve efficient GOx immobilization while maintaining biocatalytic activity. Plasma ecoprocesses, amino-bearing biopolymer-chitosan, as well as a bio-crosslinker genipin have been used efficiently on conductive carbon and non-conductive polyester-PET nonwovens. In certain cases, immobilized GOx can retain high catalytic activity after multiple cycles, making them an effective biocatalyst for organic dye degradation (Crystal Violet and Remazol Blue) via bio-Fenton reactions, including total heterogeneous bio-Fention system. Moreover, the conductive carbon felt-based bioelectrodes successfully supported simultaneous pollutant degradation and energy generation in a BEF system. This work highlights the potential of textile-based enzyme immobilization for sustainable wastewater treatment, bio-electrochemical energy conversion, and also for bacterial deactivation. Future research will focus on optimizing enzyme stability and enhancing BEF efficiency for large-scale applications. Full article

Decades of technological advancements have led to major environmental concerns, particularly the bioaccumulation of heavy metals, which pose persistent risks to ecosystems and human health. Consequently, research has increasingly shifted from conventional remediation techniques toward more sustainable, environmentally friendly solutions. This review explores recent advancements, ongoing challenges, and future perspectives in the field of bioremediation, emphasizing its potential as a green technology for heavy metal decontamination. Despite significant progress, key challenges remain, including scalability limitations and the management of bioremediation by-products, along with the influence of regulatory policies and public perception on its large-scale implementation. Emerging approaches such as genetic engineering and nanotechnology show promise in overcoming these limitations. Gene editing allows the tailoring of specific metabolic traits for bioprocesses targeted towards increased tolerance to pollutants and higher biodegradation efficiency, higher enzymatic specificity and affinity, and improved yield and fitness in plants. Nanotechnologies, particularly biogenic nanostructures, open up the possibility of repurposing waste materials as well as harnessing the advantages of the biosynthesis of NPs with higher stability, biocompatibility, and biostimulant capacities. Furthermore, biopolymers and bio-based nanocomposites can improve the efficiency and costs of bioremediation protocols. Even so, further research is essential to evaluate their long-term risks and feasibility. Full article

The presence of opportunistic pathogens, such as the Enterobacter cloacae complex (ECC), in fresh vegetables poses a significant health risk, particularly amid the ongoing antibiotic resistance crisis. Traditional chemical decontamination methods are often ineffective and these are associated with issues such as cross-resistance between antibiotics and biocides, highlighting the need for alternative approaches. This study describes the isolation of a novel phage, FENT2, with anti-ECC activity, obtained from cattle farm sewage. Belonging to the Seunavirus genus, FENT2 did not carry genes associated with lysogenic cycle, antimicrobial resistance, or virulence factors. The phage demonstrated lytic activity against the host strain E. kobei AG07E, which harbored the mcr-9 gene, exhibiting a narrow host range that also included E. ludwigii strains. In vitro assays using BioTrac (SY-LAB) impedance technology confirmed the sustained lytic activity of FENT2 under food-related stress conditions, including pH levels from 5 to 7 and NaCl concentrations up to 2%. Furthermore, FENT2 demonstrated bactericidal potential on lettuce leaves, achieving 1 log reduction in bacterial counts of the host strain after 30 min immersion treatment. These findings highlight FENT2 as a promising candidate for biocontrol applications, offering a sustainable alternative to conventional decontamination methods for reducing antimicrobial-resistant ECC contamination in fresh produce. Full article

Background: The purpose of this work was to demonstrate the ozone efficacy for disinfection of the PHARMODUCT^® automatic dispensing system for antineoplastic preparation, as a guarantee of a higher grade of cleanliness. While the use of ozone gas disinfection is almost consolidated in food and water treatment, there is a lack of scientific data in the pharmaceutical field. The scope of this study was to demonstrate the ozone efficacy for disinfection of the PHARMODUCT^® automatic dispensing system, before starting the antineoplastic preparation, in order to ensure a high degree of cleanliness and, at the same time, to define a biodecontamination procedure that could also be translatable to other automated compounding systems on the market. Methods: Ozone efficacy was determined by calculating the difference (pre-exposure–post-exposure) in CFU counts on the plate. A group of four different ATCC-selected microbial strains were tested using two distinct cycles. The first one was evaluated with an ozone gas concentration of 40 ppm for 40 min; the second cycle increased the concentration to 60 ppm for the same duration. Results: Results showed that exposure to 40 ppm ozone gas led to a 4-log reduction of all tested ATCC strains. In contrast, exposure to 60 ppm ensured a 6-log reduction. Conclusions: The ozone disinfection process, applied to the PHARMODUCT^® system, provides a superior grade of cleanliness compared to the manual disinfection procedure, thus offering insight beyond the current anti-inflammatory and analgesic application of ozone therapy in the medical field. Full article

Increasing water pollution by bio-recalcitrant contaminants necessitates the use of robust treatment methods. Individual treatment methods are not effective against these emerging organic pollutants due to their stability in the environment. This has necessitated the use of advanced integrated systems such as photocatalytic membranes. Synergy in the reactive photocatalytic membranes effectively degrades the emerging organic pollutants. This review presents the state of the art in the synthesis and application of photocatalytic membranes in water and wastewater treatment. The study critically evaluates pertinent aspects required to improve the performance of photocatalytic membranes, such as tailored material synthesis, membrane fouling control, improved photocatalyst light absorption, use of visible light from sunlight, enhanced reaction kinetics through synergy, and regeneration and reuse. Previous studies report on the effectiveness of photocatalytic membranes in the removal of organic contaminants in synthetic and actual wastewater. As such, they show great potential in wastewater decontamination; however, they also face limitations that need to be addressed. The review identifies the challenges and provides a way forward in increasing the photoactivity of titanium oxide, fouling mitigation, scalability, improving cost effectiveness, enhancing membrane stability, and other aspects relevant in scaling up efforts from the lab scale to industrial scale. Full article

The design of multi-purpose decontaminants with environmentally friendly characteristics, low cost, and high efficiency in removing pollutants from the environment is an effective and economic strategy for maintaining the long-term development of the ecosystem. Based on the strategy of killing two birds with one stone, an egg white (EW)/TiO₂ hydrogel with a porous structure is devised as a bio-adsorbent using waste eggs nearing their expiration date for simultaneously achieving the efficient removal of organic dyes and the inactivation of microorganisms from industrial wastewater. The characterizations of its morphology and composition using scanning electron microscopy (SEM), the Brunauer–Emmett–Teller (BET) theory, energy-dispersive spectrometry (EDS), Fourier transform infrared spectroscopy (FTIR), and a thermogravimetric analyzer (TGA) validate the successful synthesis of EW/TiO₂. The maximum adsorption capacity of EW/TiO₂ is 333.172 mg∙mL⁻¹ according to the Langmuir model. The photodegradation of a methyl blue (MB) solution under irradiation via a xenon lamp is used to assess the photocatalytic behavior of EW/TiO₂. Among the different samples, the 5 wt% TiO₂-doped EW/TiO₂ hydrogel shows an efficiency of 99% for 120 min of irradiation. Finally, the antibacterial properties of the EW/TiO₂ hydrogel are evaluated by calculating its bacterial survival rate against Escherichia coli (E. coli). The EW/TiO₂ photocatalyst exhibits a photocatalytic inactivation efficiency of 90.4%, indicating that the EW/TiO₂ hydrogel possesses positive antibacterial activity via effectively inhibiting the growth of the bacteria, which is suitable for industrial wastewater treatment over a long period of time. Full article

A magnetic bio-based adsorbent derived from H₂O₂-activated zeolite and turmeric carbohydrate polymer was fabricated, characterized, and utilized in removing methylene blue (MB) dye at pH 8.0 and temperatures between 25 and 55 °C. To understand the molecular-scale adsorption mechanism, a range of advanced statistical physics models were employed in conjunction with conventional equilibrium models. The as-synthesized biosorbent presented high maximum capacities according to the Langmuir model, with values ranging from 268.67 to 307.73 mg/g. The double-layer equation yielded the best-fitting results to the MB experimental data among the applied statistical physics models. The number of MB molecules ranged from 1.14 to 1.97, suggesting a multi-molecular mechanism with a non-parallel orientation. The main factor affecting the effectiveness of this adsorbent was the density of its functional groups, which varied from 27.7 to 142.1 mg/g. Adsorption energies in the range of 19.22–21.69 kJ/mol were obtained, representing the existence of physical forces like hydrogen bonds and electrostatic interactions. To complete the macroscopic examination of the MB adsorption mechanism, thermodynamic parameters such as entropy, Gibbs free energy, and internal energy were considered. The adsorption/desorption outcomes up to five cycles displayed the stability of the magnetic biosorbent and its potential for decontaminating industrial effluents. Overall, this work increases our understanding of the MB adsorption mechanism onto the produced biosorbent at the molecular level. Full article

Contaminated sediments may induce long-term risks to humans and ecosystems due to the accumulation of priority and emerging inorganic and organic pollutants having toxic and bio-accumulation properties that could become a secondary pollution source. This study focused on the screening of novel bio-based materials to be used in the decontamination of marine sediments considering technical and environmental criteria. It aimed to compare the environmental impacts of cellulose-based adsorbents produced at lab scale by using different syntheses protocols that involved cellulose functionalization by oxidation and branching, followed by structuring of an aerogel-like material via Soxhlet extraction and freeze-drying or their combination. As model pollutants, we used 4-nitrobenzaldehyde, 4-nitrophenol, methylene blue, and two heavy metals, i.e., cadmium and chromium. When comparing the three materials obtained by only employing the Soxhlet extractor with different solvents (without freeze-dying), it was observed that the material obtained with methanol did not have a good structure and was rigid and more compact than the others. A Life Cycle Assessment (LCA) was conducted to evaluate the environmental performance of the novel materials. Apart from the hierarchical categorization of the materials based on their technical and environmental performance in eliminating organic pollutants and heavy metal ions, it was demonstrated that the cellulose-based material obtained via Soxhlet extraction with ethanol was a better choice, since it had lower environmental impacts and highest adsorption capacity for the model pollutants. LCA is a useful tool to optimize the sustainability of sorbent materials alongside lab-scale experiments and confirms that the right direction to produce new performant and sustainable adsorbent materials involves not only choosing wastes as starting materials, but also optimizing the consumption of electricity used for the production processes. The main results also highlight the need for precise data in LCA studies based on lab-scale processes and the potential for small-scale optimization to reduce the environmental impacts. Full article

Polymicrobial biofilm removal and decontamination of the implant surface is the most important goal in the treatment of periimplantitis. The aim of this study is to evaluate the efficacy of four different decontamination methods for removing Acinetobacter baumannii and Staphylococcus aureus biofilms in vitro. Seventy-five dental implants were contaminated with a bacterial suspension and randomly divided into five groups (n = 15): the negative control group, which received no treatment; the positive control group, treated with 0.2% chlorhexidine; group 1, treated with a chitosan brush (Labrida BioCleanTM, Labrida AS, Oslo, Norway); group 2, treated with a chitosan brush and 0.2% chlorhexidine; and group 3, treated with a device based on the electrolytic cleaning method (GalvoSurge, GalvoSurge Dental AG, Widnau, Switzerland). The colony-forming unit (CFU) count was used to assess the number of viable bacteria in each sample, and statistical analyses were performed. When compared to the negative control group, all the decontamination methods reduced the CFU count. The electrolytic cleaning method decontaminated the implant surface more effectively than the other three procedures, while the chitosan brush was the least effective. Further research in more realistic settings is required to assess the efficacy of the decontamination procedures described in this study. Full article

Phytoremediation is an eco-friendly technology that utilizes plants and plant–microbe interactions to remove a wide spectrum of organic and inorganic pollutants from contaminated environments such as soils, waters and sediments. This low-impact, environmentally sustainable and cost-effective methodology represents a valuable alternative to expensive physical and chemical approaches, characterized by secondary pollution risks, and is gaining increasing attention from researchers and popular acceptance. In this review, the main mechanisms underlying the decontamination activity of plants have been clarified, highlighting the environmental remediation in fertility and soil health. Studies have illustrated the high potential of phytoremediation coupled with green and sustainable biocatalytic processes, which together represent a non-polluting alternative for the conversion of plant biomass into renewable resources. The convenience of this technology also lies in the valorization of the bio-wastes towards biofuels, energy purposes and value-added products, contributing to an effective and sustainable circular approach to phyto-management. The strategy proposed in this work allows, with the use of totally green technologies, the recovery and valorization of contaminated soil and, at the same time, the production of bioenergy with high efficiency, within the framework of international programs for the development of the circular economy and the reduction of greenhouse carbon emissions. Full article

(1) Background: Nanostructured cellulose has emerged as an efficient bio-adsorbent aerogel material, offering biocompatibility and renewable sourcing advantages. This study focuses on isolating (ligno)cellulose nanofibers ((L)CNFs) from barley straw and producing aerogels to develop sustainable and highly efficient decontamination systems. (2) Methods: (Ligno)cellulose pulp has been isolated from barley straw through a pulping process, and was subsequently deconstructed into nanofibers employing various pre-treatment methods (TEMPO-mediated oxidation process or PFI beater mechanical treatment) followed by the high-pressure homogenization (HPH) process. (3) Results: The aerogels made by (L)CNFs, with a higher crystallinity degree, larger aspect ratio, lower shrinkage rate, and higher Young’s modulus than cellulose aerogels, successfully adsorb and remove organic dye pollutants from wastewater. (L)CNF-based aerogels, with a quality index (determined using four characterization parameters) above 70%, exhibited outstanding contaminant removal capacity over 80%. The high specific surface area of nanocellulose isolated using the TEMPO oxidation process significantly enhanced the affinity and interactions between hydroxyl and carboxyl groups of nanofibers and cationic groups of contaminants. The efficacy in adsorbing cationic dyes in wastewater onto the aerogels was verified by the Langmuir adsorption isotherm model. (4) Conclusions: This study offers insights into designing and applying advanced (L)CNF-based aerogels as efficient wastewater decontamination and environmental remediation platforms. Full article

To accelerate the depletion of total petroleum hydrocarbons, a hydrocarburoclastic ascomycetes, Lambertella sp. MUT 5852, was bioaugmented to dredged sediments co-composting with a lignocellulosic matrix. After only 28 days of incubation, a complete depletion of the contamination was observed. The 16S rDNA metabarcoding of the bacterial community and a predictive functional metagenomic analysis were adopted to evaluate potential bacterial degrading and detoxifying functions. A combination of toxicological assays on two eukaryotic models, the root tips of Vicia faba and the human intestinal epithelial Caco-2 cells, was adopted to assess the robustness of the process not only for the decontamination but also for the detoxification of the dredged sediments. Bacterial taxa, such as Kocuria and Sphingobacterium sps., resulted to be involved in both the decontamination and detoxification of the co-composting dredged sediments by potential activation of diverse oxidative processes. At the same time, the Kocuria sp. showed plant growth-promoting activity by the potential expression of the 1-aminocyclopropane-1-carboxylate deaminase activity, providing functional traits of interest for a technosol in terms of sustaining primary producer growth and development. Full article

During the last decade, the consumption of plastics has increased highly in parallel with plastic waste. The transition towards a circular economy is the only way to prevent the environment from landfilling and incineration. This review details the recycling techniques with a focus on mechanical recycling of polymers, which is the most known and developed technique in industries. The different steps of mechanical recycling have been highlighted, starting from sorting technologies to the different decontamination processes. This paper covers degradation mechanisms and ways to improve commodity polymers (Polyolefins), engineering polymers (PET, PA6), and bio-sourced polymers (PLA and PHB). Full article

Background cold atmospheric plasma (CAP) is known to be a surface-friendly yet antimicrobial and activating process for surfaces such as titanium. The aim of the present study was to describe the decontaminating effects of CAP on contaminated collagen membranes and their influence on the properties of this biomaterial in vitro. Material and Methods: A total of n = 18 Bio-Gide^® (Geistlich Biomaterials, Baden-Baden, Germany) membranes were examined. The intervention group was divided as follows: n = 6 membranes were treated for one minute, and n = 6 membranes were treated for five minutes with CAP using kINPen^® MED (neoplas tools GmbH, Greifswald, Germany) with an output of 5 W, respectively. A non-CAP-treated group (n = 6) served as the control. The topographic alterations were evaluated via X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Afterward, the samples were contaminated with E. faecalis for 6 days, and colony-forming unit (CFU) counts and additional SEM analyses were performed. The CFUs increased with CAP treatment time in our analyses, but SEM showed that the surface of the membranes was essentially free from bacteria. However, the deeper layers showed remaining microbial conglomerates. Furthermore, we showed, via XPS analysis, that increasing the CAP time significantly enhances the carbon (carbonyl group) concentration, which also correlates negatively with the decontaminating effects of CAP. Conclusions: Reactive carbonyl groups offer a potential mechanism for inhibiting the growth of E. faecalis on collagen membranes after cold atmospheric plasma treatment. Full article