Nickel-based perovskite-catalysed direct phenol-to-aniline liquid-phase transformations.

Liquid phase direct amination of phenols to primary anilines with hydrazine was achieved using commercial NiLa-perovskite catalysts as bifunctional Lewis acid/redox-active catalysts without adding any external hydride sources. The amination strategy took place efficiently in the absence of any amount of reducing gasses (H2/NH3) and noble metals under mild conditions.

Ball-Milling Enhanced UV Protection Performance of Ca2Fe-Sulisobenzone Layered Double Hydroxide Organic Clay.

Using a co-precipitation technique, the anionic form of sulisobenzone (benzophenone-4) sunscreen ingredient was incorporated into the interlayer space of CaFe-hydrocalumite for the first time. Using detailed post-synthetic millings of the photoprotective nanocomposite obtained, we aimed to study the mechanochemical effects on complex, hybridized layered double hydroxides (LDHs). Various physicochemical properties of the ground and the intact LDHs were compared by powder X-ray diffractometry, N2 adsorption-desorption, UV-Vis diffuse reflectance, infrared and Raman spectroscopy, scanning electron microscopy and thermogravimetric measurements. The data showed significant structural and morphological deformations, surface and textural changes and multifarious thermal behavior. The most interesting development was the change in the optical properties of organic LDHs; the milling significantly improved the UV light blocking ability, especially around 320 nm. Spectroscopic results verified that this could be explained by a modification in interaction between the LDH layers and the sulisobenzone anions, through modulated π-π conjugation and light absorption of benzene rings. In addition to the vibrating mill often used in the laboratory, the photoprotection reinforcement can also be induced by the drum mill grinding system commonly applied in industry.

Influence of rapid heat treatment on the photocatalytic activity and stability of calcium titanates against a broad range of pollutants.

Calcium titanate (CTO) photocatalysts were synthesized using a sol-gel method by adopting a cost-efficient, rapid calcination technique. The CTOs were characterized by X-ray diffractometry, X-ray photoelectron spectroscopy, infrared spectroscopy, nitrogen adsorption, porosimetry measurements, scanning/transmission electron microscopy, and diffuse reflectance spectroscopy. Their photocatalytic activity was assessed through the photocatalytic degradation of phenol, oxalic acid, and chlorophenol under UV light exposure, using a commercial CTO as a reference. The stability of the samples was evaluated using compounds with -OH, -COOH, and -Cl functional groups. Characterization results showed that CTO composites containing anatase, rutile, and brookite titania were obtained. Increasing the calcination temperature led to various crystalline compositions, higher crystallinity, larger primary crystallite sizes, and smaller specific surface areas. The photocatalytic activity of all CTO/TiO2 composites was superior compared to the commercial CTO we used as a reference. The high photocatalytic activity of the best-performing composites was attributed to their higher specific surface areas and the synergistic effect between the crystal phases. A cost comparison was also made between our unique calcination technique and conventional calcination, and it was found that our method is approximately 35% more cost-effective, while retaining the photocatalytic activity.

Treatments with Diquat Reveal the Relationship between Protein Phosphatases (PP2A) and Oxidative Stress during Mitosis in Arabidopsis thaliana Root Meristems.

Reversible protein phosphorylation regulates various cellular mechanisms in eukaryotes by altering the conformation, activity, localization, and stability of substrate proteins. In Arabidopsis thaliana root meristems, histone post-translational modifications are crucial for proper cell division, and they are also involved in oxidative stress signaling. To investigate the link between reactive oxygen species (ROS) and mitosis, we treated various Arabidopsis genotypes, including wild-types and mutants showing dysfunctional PP2A, with the ROS-inducing herbicide diquat (DQ). Studying the c3c4 double catalytic subunit mutant and fass regulatory subunit mutants of PP2A provided insights into phosphorylation-dependent mitotic processes. DQ treatment reduced mitotic activity in all genotypes and caused early mitotic arrest in PP2A mutants, likely due to oxidative stress-induced damage to essential mitotic processes. DQ had a minimal effect on reversible histone H3 phosphorylation in wild-type plants but significantly decreased phospho-histone H3 levels in PP2A mutants. Following drug treatment, the phosphatase activity decreased only in the stronger phenotype mutant plants (fass-5 and c3c4). Our findings demonstrate that (i) the studied PP2A loss-of-function mutants are more sensitive to increased intracellular ROS and (ii) DQ has indirect altering effects of mitotic activities and histone H3 phosphorylation. All these findings underscore the importance of PP2A in stress responses.

Current insights into the green synthesis, in planta characterization and phytoeffects of nickel nanoparticles and their agricultural implications.

The intensifying production and release into the environment as well as the increasing potential in agricultural applications make the relationship between plants and nickel nanoparticles (Ni NPs) a relevant and timely topic. The aim of this review is to give an overview and discuss the latest findings about the relationship of Ni NPs and plants. Ni NPs can be synthesized using phytochemicals derived from plant parts in an environmentally friendly manner. There are several ways for these nanoparticles to enter plant cells and tissues. This can be demonstrated through various imaging and chemical mapping approaches (e.g., transmission electron microscopy, X-ray fluorescence spectroscopy etc.). NiO NPs affect plants at multiple levels, including subcellular, cellular, tissue, organ, and whole-plant levels. However, the effects of Ni NPs on plants' ecological partners (e.g., rhizobiome, pollinators) remain largely unknown despite their ecotoxicological significance. The main cause of the Ni NPs-triggered damages is the reactive oxygen species imbalance as a consequence of the modulation of antioxidants. In non-tolerant plants, the toxicity of NiO NPs can be mitigated by exogenous treatments such as the application of silicon, salicylic acid, or jasmonic acid, which induce defense mechanisms whereas Ni-hypertolerant plant species possess endogenous defense systems, such as cell wall modifications and nitrosative signaling against NiO NP stress. Research highlights the role of Ni NPs in managing fungal diseases, showcasing their antifungal properties against specific pathogens. Due to the essentiality of Ni, the application of Ni NPs as nanofertilizers might be promising and has recently started to come into view.

Urgent needs for second life using and recycling design of wasted electric vehicles (EVs) lithium-ion battery: a scientometric analysis.

Currently, lithium-ion batteries are increasingly widely used and generate waste due to the rapid development of the EV industry. Meanwhile, how to reuse "second life" and recycle "extracting of valuable metals" of these wasted EVBs has been a hot research topic. The 4810 relevant articles from SCI and SSCI Scopus databases were obtained. Scientometric analysis about second life using and recycling methodologies of wasted EVBs was conducted by VOSviewer, Pajek, and Netdraw. According to analytical results, the research of second life using and recycling mythologies has been growing and the expected achievement will continue to increase. China, Germany, the USA, Italy, and the UK are the most active countries in this field. Tsinghua University in China, "Fraunhofer ISI, Karlsruhe" in Germany, and "Polytechnic di Torino" in Italy are the most productive single and collaborative institutions. The journals SAE technical papers and World Electric Vehicle Journal have the highest publication and citations than other journals. Chinese author "Li Y" has the highest number of 36 publications, and his papers were cited 589 times by other authors. By analyzing the co-occurrence and keywords, energy analysis, second life (stationary using, small industry), and treatment methods, (hydrometallurgy and pyrometallurgical, electrochemical, bio-metallurgical) were the hot research topics. The S-curve from the article indicates hydrometallurgical and bio-metallurgical methods are attached with great potential in the near future. Further, different treatment methodologies are observed especially advanced techniques in hydrometallurgical, and spent medium bioleaching techniques in bio-metallurgical are good, economically cheap, has low CO2 emission, environmentally friendly, and has high recovery rate. Finally, this research provides information on second life use and top recycling methodology opportunities for future research direction for researchers and decision-makers who are interested in this research.

High-Entropy Oxides: A New Frontier in Photocatalytic CO2 Hydrogenation.

Herein, we investigate the potential of nanostructured high-entropy oxides (HEOs) for photocatalytic CO2 hydrogenation, a process with significant implications for environmental sustainability and energy production. Several cerium-oxide-based rare-earth HEOs with fluorite structures were prepared for UV-light driven photocatalytic CO2 hydrogenation toward valuable fuels and petrochemical precursors. The cationic composition profoundly influences the selectivity and activity of the HEOs, where the Ce0.2Zr0.2La0.2Nd0.2Sm0.2O2-δ catalyst showed outstanding CO2 activation (14.4 molCO kgcat-1 h-1 and 1.27 molCH3OH kgcat-1 h-1) and high methanol and CO selectivity (7.84% CH3OH and 89.26% CO) under ambient conditions with 4 times better performance in comparison to pristine CeO2. Systematic tests showed the effect of a high-entropy system compared to midentropy oxides. XPS, in situ DRIFTS, as well as DFT calculation elucidate the synergistic impact of Ce, Zr, La, Nd, and Sm, resulting in an optimal Ce3+/Ce4+ ratio. The observed formate-routed mechanism and a surface with high affinity to CO2 reduction offer insights into the photocatalytic enhancement. While our findings lay a solid foundation, further research is needed to optimize these catalysts and expand their applications.

Optimized Pt-Co Alloy Nanoparticles for Reverse Water-Gas Shift Activation of CO2.

Different Co contents were used to tune bimetallic Pt-Co nanoparticles with a diameter of 8 nm, resulting in Pt:Co ratios of 3.54, 1.51, and 0.96. These nanoparticles were then applied to the MCF-17 mesoporous silica support. The synthesized materials were characterized with HR-TEM, HAADF-TEM, EDX, XRD, BET, ICP-MS, in situ DRIFTS, and quasi in situ XPS techniques. The catalysts were tested in a thermally induced reverse water-gas shift reaction (CO2:H2 = 1:4) at atmospheric pressure in the 200-700 °C temperature range. All bimetallic Pt-Co particles outperformed the pure Pt benchmark catalyst. The nanoparticles with a Pt:Co ratio of 1.51 exhibited 2.6 times higher activity and increased CO selectivity by 4% at 500 °C. Experiments proved that the electron accumulation and alloying effect on the Pt-Co particles are stronger with higher Co ratios. The production of CO followed the formate reaction pathway on all catalysts due to the face-centered-cubic structure, which is similar to the Pt benchmark. It is concluded that the enhanced properties of Co culminate at a Pt:Co ratio of 1.51 because decreasing the ratio to 0.96 results in lower activity despite having more Co atoms available for the electronic interaction, resulting in the lack of electron-rich Pt sites.

Microcystin-LR, a cyanotoxin, modulates division of higher plant chloroplasts through protein phosphatase inhibition and affects cyanobacterial division.

Microcystin-LR (MC-LR) is a harmful cyanotoxin that inhibits 1 and 2A serine-threonine protein phosphatases. This study examines the influence of MC-LR on chloroplast division and the underlying mechanisms and consequences in Arabidopsis. MC-LR increased the frequency of dividing chloroplasts in hypocotyls in a time range of 1-96 h. At short-term exposures to MC-LR, small-sized chloroplasts (longitudinal diameters ≤6 µm) were more sensitive to these stimulatory effects, while both small and large chloroplasts showed stimulations at long-term exposure. After 48 h, the cyanotoxin increased the frequency of small-sized chloroplasts, indicating the stimulation of division. MC-LR inhibited protein phosphatases in whole hypocotyls and isolated chloroplasts, while it did not induce oxidative stress. We show for the first time that total cellular phosphatases play important roles in chloroplast division and that particular chloroplast phosphatases may be involved in these processes. Interestingly, MC-LR has a protective effect on cyanobacterial division during methyl-viologen (MV) treatments in Synechococcus PCC6301. MC-LR production has harmful effects on ecosystems and it may have an ancient cell division regulatory role in stressed cyanobacterial cells, the evolutionary ancestors of chloroplasts. We propose that cytoplasmic (eukaryotic) factors also contribute to the relevant effects of MC-LR in plants.

Application of Alcohols to Inhibit the Formation of Ca(II) Dodecyl Sulfate Precipitate in Aqueous Solutions.

The presence of alkaline earth cations, in particular, Ca2+ and Mg2+ ions in brine, causes undesired effects in solutions containing anionic surfactants because of precipitate formation. In the present study, an anionic surfactant, sodium dodecyl sulfate (SDS), was investigated, focusing on the determination of various properties (surface tension, critical micelle concentration, micelle size, turbidity) in the presence of alcohols and, in particular, the inhibition of the precipitation of SDS with calcium ions. The calcium ions were added to the surfactant in increasing concentrations (3.0-10.0 g/L), and short-carbon-chain alcohols (methanol, ethanol, n-propanol and n-butanol) were used to shift the onset of precipitate formation. The critical micelle concentration (CMC) of SDS in the presence of alcohols was also determined. It was established that among these alcohols, methanol and ethanol did not exert significant effects on the solubility of the Ca(DS)2 precipitate, while n-propanol and n-butanol were found to be much more efficient inhibitors. In addition, all the alcohols in the applied concentration range (up to 20 V/V%) were found to decrease the critical micelle concentration of SDS.

Design of Bismuth Tungstate Bi2WO6 Photocatalyst for Enhanced and Environmentally Friendly Organic Pollutant Degradation.

In this study, a chemical precipitation approach was adopted to produce a photocatalyst based on bismuth tungstate Bi2WO6 for enhanced and environmentally friendly organic pollutant degradation. Various tools such as X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), optical spectroscopy and X-ray photoelectron spectroscopy, were employed to assess the structural and morphological properties. Hence, the XRD profiles showed a well crystallized Bi2WO6 orthorhombic phase. The photocatalytic performance of the resulting photocatalyst was assessed by the decomposition of Rhodamine B (RhB) and methyl orange (MO) with a decomposition efficiency of 97 and 92%, along with the highest chemical oxygen demand of 82 and 79% during 120 min of illumination, respectively. The principal novelty of the present work is to focus on the changes in the crystalline structure, the morphology, and the optical and the photoelectrochemical characteristics of the Bi2WO6, by tuning the annealing temperature of the designed photocatalyst. Such physicochemical property changes in the as-prepared photocatalyst will affect in turn its photocatalytic activity toward the organic pollutant decomposition. The photocatalytic mechanism was elaborated based on electrochemical impedance spectroscopy, photocurrent analysis, photoluminescence spectroscopy, and radical trapping measurements. The overall data indicate that the superoxide O2•- and holes h+ are the principal species responsible for the pollutant photodegradation.

Antimicrobial and antioxidant activity of encapsulated tea polyphenols in chitosan/alginate-coated zein nanoparticles: a possible supplement against fish pathogens in aquaculture.

Regulation of antibiotic use in aquaculture calls for the emergence of more sustainable alternative treatments. Tea polyphenols (GTE), particularly epigallocatechin gallate (EGCG), have various biological activities. However, tea polyphenols are susceptible to degradation. In this work, EGCG and GTE were encapsulated in zein nanoparticles (ZNP) stabilized with alginate (ALG) and chitosan (CS) to reduce the degradation effect. ALG-coated ZNP and ALG/CS-coated ZNP encapsulating EGCG or GTE were obtained with a hydrodynamic size of less than 300 nm, an absolute ζ-potential value >30 mV, and an encapsulation efficiency greater than 75%. The antioxidant capacity of the encapsulated substances, although lower than that of the free ones, maintained high levels. On the other hand, the evaluation of antimicrobial activity showed greater efficiency in terms of growth inhibition for ALG/CS-ZNP formulations, with average overall values of around 60%, reaching an inhibition of more than 90% for Photobacterium damselae. These results support encapsulation as a good strategy for tea polyphenols, as it allows maintaining significant levels of antioxidant activity and increasing the potential for antimicrobial activity, in addition to increasing protection against sources of degradation.

Nickel oxide nanoparticles induce cell wall modifications, root anatomical changes, and nitrosative signaling in ecotypes of Ni hyperaccumulator Odontarrhena lesbiaca.

The industrial application and environmental release of nickel oxide NPs (NiO NPs) is increasing, but the details of their relationship with plants are largely unknown. In this work, the cellular, tissue, organ, and molecular level responses of three ecotypes of Ni hyperaccumulator Odontarrhena lesbiaca grown in the presence of high doses of NiO NP (250 mg/L and 500 mg/L) were studied. All three ecotypes showed a similar accumulation of Ni in the presence of nano Ni, and in the case of NiO NPs, the root-to-shoot Ni translocation was slighter compared to the bulk Ni. In all three ecotypes, the walls of the root cells effectively prevented internalization of NiO NPs, providing cellular defense against Ni overload. Exposure to NiO NP led to an increase in cortex thickness and the deposition of lignin-suberin and pectin in roots, serving as a tissue-level defense mechanism against excessive Ni. Exposure to NiO NP did not modify or cause a reduction in some biomass parameters of the Ampeliko and Loutra ecotypes, while it increased all parameters in Olympos. The free salt form of Ni exerted more negative effects on biomass production than the nanoform, and the observed effects of NiO NPs can be attributed to the release of Ni ions. Nitric oxide and peroxynitrite levels were modified by NiO NPs in an ecotype-dependent manner. The changes in the abundance and activity of S-nitrosoglutathione reductase protein triggered by NiO NPs suggest that the enzyme is regulated by NiO NPs at the post-translational level. The NiO NPs slightly intensified protein tyrosine nitration, and the slight differences between the ecotypes were correlated with their biomass production in the presence of NiO NPs. Overall, the Odontarrhena lesbiaca ecotypes exhibited tolerance to NiO NPs at the cellular, tissue, organ/organism and molecular levels, demonstrating various defense mechanisms and changes in the metabolism of reactive nitrogen species metabolism and nitrosative protein modification.

Pt/MnO Interface Induced Defects for High Reverse Water Gas Shift Activity.

The implementation of supported metal catalysts heavily relies on the synergistic interactions between metal nanoparticles and the material they are dispersed on. It is clear that interfacial perimeter sites have outstanding skills for turning catalytic reactions over, however, high activity and selectivity of the designed interface-induced metal distortion can also obtain catalysts for the most crucial industrial processes as evidenced in this paper. Herein, the beneficial synergy established between designed Pt nanoparticles and MnO in the course of the reverse water gas shift (RWGS) reaction resulted in a Pt/MnO catalyst having ≈10 times higher activity compared to the reference Pt/SBA-15 catalyst with >99 % CO selectivity. Under activation, a crystal assembly through the metallic Pt (110) and MnO evolved, where the plane distance differences caused a mismatched-row structure in softer Pt nanoparticles, which was identified by microscopic and surface-sensitive spectroscopic characterizations combined with density functional theory simulations. The generated edge dislocations caused the Pt lattice expansion which led to the weakening of the Pt-CO bond. Even though MnO also exhibited an adverse effect on Pt by lowering the number of exposed metal sites, rapid desorption of the linearly adsorbed CO species governed the performance of the Pt/MnO in the RWGS.

Highly Porous Polymer Beads Coated with Nanometer-Thick Metal Oxide Films for Photocatalytic Oxidation of Bisphenol A.

Highly porous metal oxide-polymer nanocomposites are attracting considerable interest due to their unique structural and functional features. A porous polymer matrix brings properties such as high porosity and permeability, while the metal oxide phase adds functionality. For the metal oxide phase to perform its function, it must be fully accessible, and this is possible only at the pore surface, but functioning surfaces require controlled engineering, which remains a challenge. Here, highly porous nanocomposite beads based on thin metal oxide nanocoatings and polymerized high internal phase emulsions (polyHIPEs) are demonstrated. By leveraging the unique properties of polyHIPEs, i.e., a three-dimensional (3D) interconnected network of macropores, and high-precision of the atomic-layer-deposition technique (ALD), we were able to homogeneously coat the entire surface of the pores in polyHIPE beads with TiO2-, ZnO-, and Al2O3-based nanocoatings. Parameters such as nanocoating thickness, growth per cycle (GPC), and metal oxide (MO) composition were systematically controlled by varying the number of deposition cycles and dosing time under specific process conditions. The combination of polyHIPE structure and ALD technique proved advantageous, as MO-nanocoatings with thicknesses between 11 ± 3 and 40 ± 9 nm for TiO2 or 31 ± 6 and 74 ± 28 nm for ZnO and Al2O3, respectively, were successfully fabricated. It has been shown that the number of ALD cycles affects both the thickness and crystallinity of the MO nanocoatings. Finally, the potential of ALD-derived TiO2-polyHIPE beads in photocatalytic oxidation of an aqueous bisphenol A (BPA) solution was demonstrated. The beads exhibited about five times higher activity than nanocomposite beads prepared by the conventional (Pickering) method. Such ALD-derived polyHIPE nanocomposites could find wide application in nanotechnology, sensor development, or catalysis.

Nitro-oxidative response to internalized multi-walled carbon nanotubes in Brassica napus and Solanum lycopersicum.

In addition to their beneficial effects on plant physiology, multi-walled carbon nanotubes (MWCNTs) are harmful to plants in elevated concentrations. This study compared the effects of two doses of MWCNT (10 and 80 mg/L) in Brassica napus and Solanum lycopersicum seedlings focusing on nitro-oxidative processes. The presence of MWCNTs was detectable in the root and hypocotyl of both species. Additionally, transmission electron microscopy analysis revealed that MWCNTs are heavily transformed within the root cells forming large aggregates. The uptake of MWCNTs negatively affected root viability and root cell proliferation of both species, but more intense toxicity was observed in S. lycopersicum compared to B. napus. The presence of MWCNT triggered more intense protein carbonylation in the relative sensitive S. lycopersicum, where increased hydrogen peroxide levels were observed. Moreover, MWCNT exposure increased the level of physiological protein tyrosine nitration which was more intense in S. lycopersicum where notable peroxynitrite accumulation occurred. These suggest for the first time that MWCNT triggers secondary nitro-oxidative stress which contributes to its toxicity. Moreover, the results indicate that the extent of the nitro-oxidative processes is associated with the extent of MWCNT toxicity.

Facile immobilization of cholesterol oxidase on Pt,Ru-C nanocomposite and ionic liquid-modified carbon paste electrode for an efficient amperometric free cholesterol biosensing.

In present work, the enzyme cholesterol oxidase (ChOx) was immobilized by Nafion® (Naf) on Pt,Ru-C nanocomposite and an ionic liquid (IL)-modified carbon paste electrode (CPE) in order to create cholesterol biosensor (Naf/ChOx/Pt,Ru-C/IL-CPE). The prepared working electrodes were characterized using scanning electron microscopy-energy-dispersive spectrometry, while their electrochemical performance was evaluated using electrochemical impedance spectroscopic, cyclic voltammetric, and amperometric techniques. Excellent synergism between IL 1-allyl-3-methylimidazolium dicyanamide ([AMIM][DCA]), Pt,Ru-C, and ChOx, as modifiers of CPE, offers the most pronounced analytical performance for improved cholesterol amperometric determination in phosphate buffer solution pH 7.50 at a working potential of 0.60 V. Under optimized experimental conditions, a linear relationship between oxidation current and cholesterol concentration was found for the range from 0.31 to 2.46 µM, with an estimated detection limit of 0.13 µM and relative standard deviation (RSD) below 5.5%. The optimized amperometric method in combination with the developed Naf/ChOx/Pt,Ru-C/IL-CPE biosensor showed good repeatability and high selectivity towards cholesterol biosensing. The proposed biosensor was successfully applied to determine free cholesterol in a human blood serum sample via its enzymatic reaction product hydrogen peroxide despite the presence of possible interferences. The percentage recovery ranged from 99.08 to 102.81%, while RSD was below 2.0% for the unspiked as well as the spiked human blood serum sample. The obtained results indicated excellent accuracy and precision of the method, concluding that the developed biosensor can be a promising alternative to existing commercial cholesterol tests used in medical practice.

Hungarian and Indonesian rice husk as bioadsorbents for binary biosorption of cationic dyes from aqueous solutions: A factorial design analysis.

The wastewater of the dye industry can be characterized by a complex chemical composition and consists of numerous dyes. Bioadsorbents are increasingly applied for the biosorption of dyes because they are inexpensive and environmentally friendly. Rice husk (RH) is a potential agricultural waste that can be converted into a bioadsorbents for the biosorption of cationic dyes. Herein, the removal of methylene blue (MB) and basic red 9 (BR9) dyes by Hungarian rice husk (HRH) and Indonesian rice husk (IRH) using binary biosorption was investigated. Adsorbents were characterized by zeta potential, Fourier-transform infrared spectroscopy, and scanning electron microscopy. Batch biosorption evaluated the influence of different variables, including pH, adsorbent dose, contact time, and initial concentrations. Several factors that influence the biosorption of MB and BR9 onto rice husk were assessed using main effect, Pareto charts, normal probability plots, and interaction effect in a factorial design. The optimum contact time was 60 min. Isotherm and kinetic models of MB and BR9 in binary biosorption fitted to the Brunauer-Emmett-Teller multilayer and the Elovich equation based on correlation coefficients and nonlinear chi-square. Results showed that the biosorption capacity of HRH was 10.4 mg/g for MB and 10 mg/g for BR9; values for IRH were 9.3 mg/g and 9.6 mg/g, respectively. Therefore, HRH and IRH were found to be effective adsorbents for removing MB and BR9 via binary biosorption.

Phosphorylated Peptide Derived from the Myosin Phosphatase Target Subunit Is a Novel Inhibitor of Protein Phosphatase-1.

Identification of specific protein phosphatase-1 (PP1) inhibitors is of special importance regarding the study of its cellular functions and may have therapeutic values in diseases coupled to signaling processes. In this study, we prove that a phosphorylated peptide of the inhibitory region of myosin phosphatase (MP) target subunit (MYPT1), R690QSRRS(pT696)QGVTL701 (P-Thr696-MYPT1690-701), interacts with and inhibits the PP1 catalytic subunit (PP1c, IC50 = 3.84 µM) and the MP holoenzyme (Flag-MYPT1-PP1c, IC50 = 3.84 µM). Saturation transfer difference NMR measurements established binding of hydrophobic and basic regions of P-Thr696-MYPT1690-701 to PP1c, suggesting interactions with the hydrophobic and acidic substrate binding grooves. P-Thr696-MYPT1690-701 was dephosphorylated by PP1c slowly (t1/2 = 81.6-87.9 min), which was further impeded (t1/2 = 103 min) in the presence of the phosphorylated 20 kDa myosin light chain (P-MLC20). In contrast, P-Thr696-MYPT1690-701 (10-500 µM) slowed down the dephosphorylation of P-MLC20 (t1/2 = 1.69 min) significantly (t1/2 = 2.49-10.06 min). These data are compatible with an unfair competition mechanism between the inhibitory phosphopeptide and the phosphosubstrate. Docking simulations of the PP1c-P-MYPT1690-701 complexes with phosphothreonine (PP1c-P-Thr696-MYPT1690-701) or phosphoserine (PP1c-P-Ser696-MYPT1690-701) suggested their distinct poses on the surface of PP1c. In addition, the arrangements and distances of the surrounding coordinating residues of PP1c around the phosphothreonine or phosphoserine at the active site were distinct, which may account for their different hydrolysis rate. It is presumed that P-Thr696-MYPT1690-701 binds tightly at the active center but the phosphoester hydrolysis is less preferable compared to P-Ser696-MYPT1690-701 or phosphoserine substrates. Moreover, the inhibitory phosphopeptide may serve as a template to synthesize cell permeable PP1-specific peptide inhibitors.

Multi-round recycling of green waste for the production of iron nanoparticles: synthesis, characterization, and prospects in remediation.

Due to the widespread applications of metal nanoparticles (NPs), green synthesis strategies have recently advanced, e.g., methods that utilize extracts made from different plant wastes. A particularly innovative approach to reducing large amounts of available household/agricultural green wastes is their application in nanoparticle generation. Regarding this, the aim of our work was to examine the possibility of upgrading green nanoparticle syntheses from an innovative economic and environmental point of view, namely by investigating the multiple recyclabilities of green tea (GT), coffee arabica (CA), and Virginia creeper (Parthenocissus quinquefolia) (VC) waste residues for iron nanoparticle (FeNPs) synthesis. The plant extracts obtained by each extraction round were analyzed individually to determine the amount of main components anticipated to be involved in NPs synthesis. The synthesized FeNPs were characterized by X-ray powder diffraction and transmission electron microscopy. The activity of the generated FeNPs in degrading chlorinated volatile organic compounds (VOC) and thus their future applicability for remediation purposes were also assessed. We have found that VC and especially GT residues could be reutilized in multiple extraction rounds; however, only the first extract of CA was suitable for FeNPs' generation. All of the obtained FeNPs could degrade VOC with efficiencies GT1-Fe 91.0%, GT2-Fe 83.2%, GT3-Fe 68.5%; CA1-Fe 76.2%; VC1-Fe 88.2%, VC2-Fe 79.7%, respectively, where the number (as in GT3) marked the extraction round. These results indicate that the adequately selected green waste material can be reutilized in multiple rounds for nanoparticle synthesis, thus offering a clean, sustainable, straightforward alternative to chemical methods.