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Lignin-modifying enzymes (LMEs) are impactful biocatalysts in environmental remediation applications. However, LMEs-assisted experimental degradation neglects the molecular basis of pollutant degradation. Furthermore, throughout the remediation process, the inherent hazards of environmental pollutants remain untapped for in-depth toxicological endpoints. In this investigation, a predictive toxicological framework and a computational framework adopting LMEs were employed to assess the hazard of Priority Pollutants (PP) and its possible LMEs-assisted catalytic screening. The potential hazardous outcomes of PP were assessed using quantitative structure-activity relationship (QSARs)-based techniques including Toxtree, ECOSAR, and T.E.S.T. tools. Toxicological findings revealed positive outcomes in a multitude of endpoints for all PP. The PP compound 2,3,7,8-TCDD (dioxin) was found to exhibit the lowest concentration of aquatic toxicity implementing aquatic model systems; LC

A functional PbO-lignin electrode hydrid material composite was designed and manufactured. Moreover, its connection efficiency was confirmed using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). We noted that the superficial layers of PbO combined with layers of the biopolymer and that oxygen atoms present in both materials had influence on the chemical environment of the neighboring compound. Hence, it can be said that the addition of PbO significantly contributes to the improvement of thermal stability of the final inorganic-organic system. In the framework of the study, the dispersive, morphological and structural characteristics were determined using scanning electron microscopy (SEM) and laser diffraction method. Electrochemical studies indicated that the PbO-lignin material exhibits better electrochemical properties compared to PbO without the addition of kraft lignin (increased capacitance, lower charge transfer resistance), as the specific capacitance after 5000 charge/discharge cycles was still at 95% of the initial value. Such promising operating parameters show that this material can be successfully used as an electrode material for energy management systems.

Studies on the identification, properties and function of chitin in sponges (Porifera), which are recognized as the first multicellular organisms on Earth, continue to be of fundamental scientific interest. The occurrence of chitin has so far been reported in 21 marine sponge species and only in two inhabiting fresh water. In this study, we present the discovery of α-chitin in the endemic demosponge Ochridaspongia rotunda, found in Lake Ohrid, which dates from the Tertiary. The presence of chitin in this species was confirmed using special staining, a chitinase test, FTIR, Raman and NEXAFS spectroscopy, and electrospray ionization mass spectrometry (ESI-MS). In contrast to the case of marine sponges, chitin in O. rotunda has been found only within its holdfast, suggesting a role of chitin in the attachment of the sponge to the hard substratum. Isolated fibrous matter strongly resemble the shape and size of the sponge holdfast with membrane-like structure.

Nanozymes are super-efficient nanomaterials with enzyme-like characteristics, as the name suggests. In the last decade, efforts have been made to develop "artificial enzymes," which are alternatives to natural enzymes. As nanoscience and nanotechnology advance, nanozymes, which are catalytic nanomaterials having enzyme-like properties, have fascinated researchers' attention. Nanozymes with unique physicochemical properties and nanomaterials that mimic catalytic activity have gained a special interest in the industrial sectors. However, several constraints have hampered their effective deployment in industrial processes, including denaturation, time-consuming manufacturing, overall high cost-ratio, and reutilization challenges. After a brief overview of nanozyme research, an analysis of the similarities and differences between nanozymes and natural and synthetic enzymes is presented. Because of their distinct properties, nanozymes stand out in this comparison. Nanozymes have exhibited a variety of applications leveraging the physiochemical properties of nanomaterials, ranging from in vitro detection to enzyme substitution in biological systems. In addition, nanozymes have introduced a new field called nanozymology, which blends nanotechnology with enzymology.

A novel non-enzymatic glucose sensor based on poly(caffeic acid)@multi-walled carbon nanotubes decorated with CuO nanoparticles (PCA@MWCNT-CuO) was developed. The described approach involves the complexation/accumulation of Cu(II) on PCA@MWCNT followed by electrochemical CuO deposition in an alkaline electrolyte. The morphology and surface characteristics of the nanomaterial were determined by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), Raman spectroscopy, and inductively coupled plasma mass spectrometry (ICP-MS). A hybrid-support sensor device was then developed to assess the glucose concentration in different solutions. The sensitivity of the electrode is 2412 μA mM

Bio-based waste materials are more often used as effective and cheap adsorbents to remove toxic organic compounds such dyes. Batch adsorption of C.I. Basic Blue 3 (BB3) onto Cladium mariscus saw-sedge was studied in comparison with sawdust obtained from various species of wood in order to explore their potential application as low-cost sorbents for basic dye removal from wastewaters. The effect of phase contact time (1–240 min), initial dye concentration (50–200 mg/L), and the auxiliaries presence (10–60 g/L NaCl and 0.1–0.75 g/L anionic surfactant) on BB3 uptake was investigated. The adsorption kinetic data followed the pseudo-second order equation rather than pseudo-first order one. The equilibrium adsorption data were analyzed using the Langmuir, Freundlich, and Tempkin isotherm models. The monolayer sorption capacities decreased from 44.29 to 42.07 mg/g for Cladium mariscus saw-sedge and from 28.69 to 27.5 mg/g for sawdust with temperature increasing from 20 to 50 °C. The thermodynamic parameters such as the change in free energy (∆G°), enthalpy (∆H°), and entropy (∆S°) were calculated, too.

In this work, new M

Introduction We present a multimodal nanoplatforms for the treatment of hepatocellular carcinoma (HCC) in vitro. The nanoplatforms are based on polydopamine (PDA)-coated magnetite nanoparticles (NPs) and spheres (sMAG) with PAMAM dendrimers and functionalized with NHS-PEG-Mal (N-hydroxysuccinimide-polyethylene glycol-maleimide) linker, which allows their functionalization with a folic acid derivative. The nanomaterials bearing a folic acid-targeting moiety show high efficiency in killing cancer cells in the dual chemo- and photothermal therapy (CT-PTT) of the liver cancer cells in comparison to modalities performed separately. Materials and methods All materials are characterized in detail with transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential and magnetic measurements. Also, photothermal properties were determined under irradiation of nanoparticles with laser beam of 2 W/cm2. The nontoxicity of nanoparticles with doxorubicin and without was checked by WST and LIVE/DEAD assay. Those tests were also used to evaluate materials bearing folic acid and anticancer drug in combined chemo- and photothermal therapy of HCC. Further, the generation of reactive oxygen species profile was also evaluated using flow cytometry test. Results Both NPs and sMAG showed high photothermal properties. Nevertheless, the higher photothermal response was found for magnetic spheres. Materials of concentration above 10 µg/mL reveal that their activity was comparable to free doxorubicin. It is worth highlighting that a functionalized magnetic sphere with DOXO more strongly affected the HepG2 cells than smaller functionalized nanoparticles with DOXO in the performed chemotherapy. This can be attributed to the larger size of particles and a different method of drug distribution. In the further stage, both materials were assessed in combined chemo- and photothermal therapy (CT-PTT) which revealed that magnetic spheres were also more effective in this modality than smaller nanoparticles. Conclusion Here, we present two types of nanomaterials (nanoparticles and spheres) based on polydopamine and PAMAM dendrimers g.5.0 functionalized with NHS-PEG-Mal linker terminated with folic acid for in vitro hepatocellular carcinoma treatment. The obtained materials can serve as efficient agents for dual chemo- and photothermal therapy of HCC. We also proved that PDA-coated magnetic spheres were more efficient in therapies based on near-infrared irradiation because determined cell viabilities for those materials are lower than for the same concentrations of nanomaterials based on small magnetic nanoparticles.

Mesoporous Al2O3 obtained via a soft template method was used as a support for the immobilization of laccase from Trametes versicolor. Porous alumina is a very attractive engineering material extensively used in catalysis, adsorption and separation. The proposed route of synthesis of Al2O3 yielded a material with high well developed parameters of the porous structure and thermal, and kinetic stability. The next stage involved typical adsorption immobilization of laccase at different pH (3–6). The support and prepared biocatalytic system were comprehensively analyzed with respect to morphology, porosity, electrokinetic and thermal stability, and characteristic functional groups. Furthermore, the oxidation reaction of sulfonic acid was used as a model reaction to evaluate the catalytic activity of obtained biocatalyst. Based on this reaction, the influence of pH and temperature on catalytic activity was determined, in addition to the system’s storage stability and reusability. The biocatalytic system exhibits catalytic activity from 40% up to 100% in the analyzed pH range 3–6 and in the temperature range 30–70 °C. Additionally, laccase immobilized onto Al2O3 retains approximately 65% of its initial activity after 30 days of storage, and around 60% after 10 reaction cycles. A suggested mechanism of laccase immobilization was also proposed.

In the presented study poly(methyl methacrylate) (PMMA) and magnetite nanoparticles were used to prepare novel PMMA/Fe3O4 electrospun nanofibers. The obtained materials were characterized, and then modified and used as supports for covalent binding and encapsulation of laccase from Trametes versicolor. High enzyme loading (63.2 mg of laccase per 1 cm2 of support) was recorded for the system after covalent binding, and the formation of stable interactions was confirmed, as leaching of the enzyme from the support did not exceed 12%. Furthermore, the obtained biocatalytic systems exhibited excellent pH, thermal and storage stability as well as reusability: after 40 days of storage and 5 successive biocatalytic cycles they retained 80% of their initial properties. Experiments on the removal of antibiotic showed that both immobilized laccases possess high ability to convert tetracycline. Under optimal process conditions (pH 5, temperature 25 °C, tetracycline solution concentration 1.0 mg L−1) the removal efficiency reached 100% and 94% for covalently bonded and encapsulated laccase. Finally, the degradation products were examined to investigate the degradation mechanism. The data showed that oxidation, dehydrogenation and demethylation are major reactions in the degradation of tetracycline using immobilized laccase. The findings demonstrate clearly that laccase immobilized by covalent binding and encapsulation using electrospun materials has the potential for application in environmental protection processes for the removal of antibiotics.

In this study, we present the concept of co-immobilization of xylose dehydrogenase and alcohol dehydrogenase from Saccharomyces cerevisiae on an XN45 nanofiltration membrane for application in the process of xylose bioconversion to xylonic acid with simultaneous cofactor regeneration and membrane separation of reaction products. During the research, the effectiveness of the co-immobilization of enzymes was confirmed, and changes in the properties of the membrane after the processes were determined. Using the obtained biocatalytic system it was possible to obtain 99% xylonic acid production efficiency under optimal conditions, which were 5 mM xylose, 5 mM formaldehyde, ratio of NAD+:NADH 1:1, and 60 min of reaction. Additionally, the co-immobilization of enzymes made it possible to improve stability of the co-immobilized enzymes and to carry out xylose conversion in six consecutive cycles and after 7 days of storage at 4 °C with over 90% efficiency. The presented data confirm the effectiveness of the co-immobilization, improvement of the stability and reusability of the biocatalysts, and show that the obtained enzymatic system is promising for use in xylose bioconversion and simultaneous regeneration of nicotinamide cofactor.

Enzymatic conversion of micropollutants into less-toxic derivatives is an important bioremediation strategy. This paper aims to critically review the progress in water and wastewater treatment by both free and immobilized enzymes presenting this approach as highly efficient and performed under environmentally benign and friendly conditions. The review also summarises the effects of inorganic and organic wastewater matrix constituents on enzymatic activity and degradation efficiency of micropollutants. Finally, application of enzymatic reactors facilitate continuous treatment of wastewater and obtaining of pure final effluents. Of a particular note, enzymatic treatment of micropollutants from wastewater has been mostly reported by laboratory scale studies. Thus, this review also highlights key research gaps of the existing techniques and provides future perspectives to facilitate the transfer of the lab-scale solutions to a larger scale and to improve operationability of biodegradation processes.

Biological treatment of water and wastewater using microorganisms and/or enzymes has surfaced asapromising approach for removal of hazardous pollutants. Particularly, enzymatic techniques, based on oxidoreductase enzymes, have several attractive advantages including high enzyme activity, sustainability, low cost, low energy requirements, andalack of toxic solvents. However, free enzymes suffer due to their low stability and extremely limited reusability. To overcome these drawbacks, enzymes' immobilization is frequently applied, which results in improvement of catalytic features of the biocatalyst and enhanced enzymes recovery and reuse. It has been reported thatakey effect on the final properties of the immobilized enzyme is selection of suitable support materials. Over recent years, progress in the synthesis of nanostructured materials has prompted their use as supports for enzyme immobilization mainly due to their unique properties, such as large surface area and small particle size. The nanoscale materials of organic, inorganic, and hybrid/composite origin are also used to immobilize enzymes such as laccase, tyrosinase, and peroxidases to produce efficient nanobiocatalysts for removal of selected water pollutants. In this chapter, we present an overview of the recent achievements in the removal of pollutants, mainly phenol and its derivatives, from water bodies using nanoimmobilized enzymes. It has been shown that such an approach results in effective removal of pollutants and its conversion into less toxic compounds compared with parent substances. However, further progress and improvements will allow enzymatic treatment of phenolic compounds to become one of the most significant removal strategies.

Synthetic hormones constitute a dangerous class of pollutants as they impose risks on the reproductive health of ecosystem life and humans via the water, including drinking water. Traditional methods of wastewater treatment seem to be inefficient. In this work, design and fabrication of a new biosystem made of CaSiO3 and laccase is reported and its application for removal of 17α-ethynylestradiol (EE2) from aqueous systems is demonstrated. EE2 is a synthetic estrogen, which is known to resist degradation. The effect of treatment time, pH, temperature, estrogen concentration and mass of the biocatalytic system was investigated. Treatment of EE2 solution (0.1mg/L) with 100mg of the biosystem for 12h at pH 5, 25 °C resulted in 100% removal efficiency. The data confirmed a synergistic degradation of estrogen resulting from simultaneous adsorption and biocatalytic conversion with a significant predominance of enzymatic conversion. The efficiency of estrogen removal by the biosystem varied depending on type of cations and anions present in the solution. After 10 cycles of repeated use, and 20 days of storage, the CaSiO3-laccase biosystem retained ~40% of its initial activity. Application of the CaSiO3-laccase biosystem significantly reduced toxicity and estrogenic activity of the solution. Finally, it was also possible to remove more than 40% of EE2 from samples of real wastewater using the CaSiO3-laccase biosystem. The method may pave the way for new efficient approaches for removal of pharmaceuticals and hormones from wastewater.

Diclofenac sodium is an anti-inflammatory drug commonly used to cure pain in various treatments. The remarkable potential of this pain-killer leads to its excessive use and, therefore, a persistent water contaminant. Its presence in aqueous bodies is hazardous for both humans and the environment because it causes the growth of harmful drug-resistant bacteria in water. Herein, we present a comparative study of the ZnO and ZnFe

Gd3+-, Pr3+- or Sm3+-doped Co-Zn (Co0.5Zn0.5Fe2O4) magnetic ferrites (i.e., Co0.5Zn0.5Gd0.1Fe1.9O4, Co0.5Zn0.5Pr0.1Fe1.9O4 and Co0.5Zn0.5Sm0.1Fe1.9O4) were prepared using a facile sol-gel approach, and the structure, surface morphology and chemical composition of the products were studied by means of scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), UV-visible diffuse reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and vibrating sample magnetometer (VSM) spectroscopy. XRD patterns show the Co-Zn product is composed of cubic spinel phases with few impurities or secondary phases, and the average crystallite sizes of the samples are determined to be approximately ∼51–80, ∼99–181, ∼68–103 and ∼83–133 nm. Also the coercivity and remnant and saturation magnetizations, evaluated by vibrating sample magnetometer (VSM), are found to increase linearly with the incorporation of Gd3+, Pr3+ and Sm3+ in the product formulation. The Co1−xZnxFe2−yRyO4 photocatalyst sample is found to display a red shift in its absorption, and exhibits outstanding photocatalytic effects in the degradation of MO under ultraviolet (UV) light. This is attributed to the reduction of the band gap of cobalt-zinc ferrite due to the presence of rare earth ions. Further in vitro evaluations of the cytotoxic effects of the synthesized nanoparticles were performed on a HeLa cell line.

This study presents proof-of-concept validation of a multi enzymatic biocatalytic system, capable of producing monosaccharides from a birch biomass pretreated liquor with simultaneous cofactor regeneration. To improve the stability of the proposed biocatalyst, co-immobilization of NAD+-dependent xylose dehydrogenases, glucose dehydrogenase, and NADH-dependent 3-hydroxybutyrate dehydrogenase was performed on mesoporous silica SBA-15. The results of the physicochemical analysis confirmed the effectiveness of enzymes deposition on the support material and changes in the surface area and porous structure of silica before and after the process. Process conditions in which the three-enzymes system allowed to achieve the highest efficiency of the conducted reactions were optimized at 20 °C, pH 7, 90 min of process duration, 400 mM of levulinic acid addition and ratio of NAD+:NADH 1:5. Results from this study demonstrate excellent xylonic acid, gluconic acid and 4-hydroxyvaleric acid production at conversion rate of 98.7%, 95.6% and 99.2%, respectively. In addition, the high stability and reusability of the developed biocatalytic system was confirmed based on tests in ten successive catalytic cycles and the storage time of 10 days at 4 °C. At the end of the tests, co-immobilized enzymes were capable of catalyzing the process with >70% efficiency. The presented data confirmed the effectiveness of co-immobilization, improvement of enzyme properties including their high reusability, as well as indicated the application potential of the proposed multienzymatic system in the conversion of components of pretreated biomass solutions.