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  • Colour is crucial for enhancing the appetizing value and consumer acceptance of food products. The commonly used food colourants and food preservatives such as Malachite Green (MG) and Copper Sulfate (CS) can cause severe health problems. This study investigates the toxicity of these food-grade colourants through acute exposure using cytotoxicity using the brine shrimp model including 3D surface analysis (3DSA) and studies Brine shrimp were treated with various concentrations of MG and CS. The cytotoxic effect was confirmed by brine shrimp lethality assay and 3DSA. Molecular docking and Molecular Dynamic simulation were done using hAChE binding cavity. Results showed that concentrations (2.5-10 µg/ml) of MG and CS significantly decreased locomotor behaviour within 1 h, while higher concentrations (10-100 µg/ml) caused high mortality rates. Morphological studies revealed that there is a significant reduction (p<0.05) in shrimp length treated with MG and CS. The 3DSA indicates that there is an inappropriate surface of the shrimp morphology. Interestingly, MG-treated shrimps had shown significant inhibition of AChE in homogenates, indicating cholinergic nerve-mediated toxicity. Computational studies showed MG confined active binding with human acetylcholinesterase (hAChE), with a binding energy MMGBSA of -51.3 kcal/mol. MD simulation confirmed reversible binding stability inside the hAChE pocket. It can be concluded that acute exposure to brine shrimps with MG and CS exhibited cytotoxicity as evidenced by the increase in mortality of the shrimps. This study further warrants the investigation of MG and CS residues from commonly used fruits and vegetables and their putative toxic effect using studies.

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  • The hypothesis that the antibacterial effect of copper depends on its state was tested. It was studied the antibacterial effect of copper applied to the fabric, copper in chelated and free (ionic) forms on the growth intensity of and in the system after a single or "primary" contact. Classical microbiology methods were used. Copper was applied to the fabric by magnetron and arc planar discharge systems, and the culture of microalgae , resistant to the action of high concentrations of copper, was used to obtain copper in chelated form. It was shown that a thin layer of copper (3 μm) applied to the fabric showed pronounced antibacterial activity against (85 % compared to the antibiotic meropenem) and less pronounced activity against , which is resistant to meropenem. Copper in ionic form inhibited the growth of as well as the antibiotic, and also effectively inhibited the growth of i.e., copper ions did not have species specificity like the antibiotic. Components of microalgae cells had weakly expressed antibacterial effect to these types of bacteria, and supplementary addition of copper sulfate to the biomass of microalgae led to an increase of their antibacterial activity and this is more pronounced for microalgae culture in which the ratio « chelated/ionic » forms of copper is shifted to the ionic form. It was shown that the antibacterial activity of microalgae biomass after the first introduction into the tested bacterial cultures depends on the amount of free or "weakly bound" with cell components copper ions. It is suggested that the antibacterial effect of fabric with a thin layer of copper may be determined by two mechanisms: the action of copper ions and mechano-bactericidal effects, while chelated forms of copper may have a prolonged effect on bacterial cultures.

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  • This study evaluated the efficacy of various inorganic materials, biological control agents, organic agricultural materials (OAMs), and essential oils for controlling cucumber powdery mildew (CPM) under greenhouse conditions. Treatments included silicate, bicarbonate, copper sulfate, sulfurbased compounds, Bacillus subtilis KB-401, Bacillus amyloliquefaciens M27, Bordeaux mixtures, chitosan combined with oxidated copper salt, chitooligosaccharides, and essential oils such as castor and rapeseed oil with lecithin. Results demonstrated that Bordeaux mixtures, particularly Bordeaux Mixture I, and sulfur-based compounds provided the most reliable CPM control among inorganic materials. Bacillus strains KB-401 and M27 achieved sustained disease suppression, suggesting their value in integrated pest management (IPM). Chitosan combined with oxidated copper salt showed high efficacy, making it a promising candidate for long-term control. Among OAMs, loess-sulfur mixtures proved especially effective in preventive applications, achieving comparable results to resistant cultivar 'Saronsamcheok'. Essential oils, including castor and rapeseed oil, also exhibited significant CPM suppression potential, although repeated applications may be necessary for sustained control. These findings highlight the potential of these environmentally friendly treatments as viable components of an IPM strategy for managing CPM in cucumber crops. Further studies are recommended to optimize combinations and application timing for enhanced efficacy.

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  • Tetrahymenosis has resulted in significant economic losses for the ornamental fish farming industry in Harbin. While previous studies have investigated the outbreaks and histopathology of Tetrahymena pyriformis in fish, there is still a lack of study on the use of the application of fish drugs for prevention and treatment. This experiment aims to evaluate the efficacy of three fish drugs (copper, Nitrofural, Methylene Blue) in combating tetrahymenosis in goldfish. We utilized eDNA-based 16 s rDNA gene amplifiers sequencing and qPCR technologies to extract environmental samples and conducted high-throughput sequencing to assess the interaction between the diversity of T. pyriformis and other microorganisms in aquaculture water following the introduction of various fish medications. Our findings revealed that among the three fish drugs test, Nitrofural displayed the most promising effects, followed by Methylene Blue, while copper sulfate proved to be the least effective. Consequently, our study provides a treatment plan for addressing tetrahymenosis in goldfish and offers insights into the pathological changes in goldfish tissues following the onset of the disease.

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  • Two new organo-inorganic hybrids, (CNH)[Cu(HO)](BeF) () and (CNH)[Cu(HO)](SeO) (), were prepared via the interaction of ethylenediamine, copper fluoroberyllate or selenate, and H[BeF]/HSeO in aqueous solutions. The structures of and are similar to each other and the previously reported (CNH)[Cu(HO)](SO): monoclinic, 2/, = 5.1044(2) Å, = 11.6171(4) Å, = 10.1178(3) Å, and β = 94.431(3)° for ; and = 5.25020(10), = 11.7500(2), = 10.4434(2), and β = 94.5464(17)° for . All structures contain a square planar [Cu(HO)] species, which coordinates, at rather long distances, two tetrahedral dianions in κ mode, forming relatively weak [Cu(HO)()] complexes. These are linked together via hydrogen bonding into pseudo-chains; the ethylenediammonium cations link them into a 3D architecture. Compound is, to the best of our knowledge, the first-though expected-representative of a hybrid organo-inorganic fluoroberyllate. The crystal chemical relations within the structural family (enH)[Cu(HO)]() are discussed.

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  • The development of phantoms to reduce animal testing or to validate new instruments or operation techniques is of increasing importance. For this reason, a blood circulation phantom was developed to test a newly designed retractor system with an integrated oxygen sensor. This phantom was used to evaluate the impact of the 3D printed blood vessel on the measurement of the oxygen saturation.

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  • This work investigates the inhibition effect and adsorption properties of a new tailor-made synthesized model molecule of ionic liquids, namely N-decyl nicotinamide bromide [CNic]Br in an acidic 0.1 M NaSO solution (pH = 2.7) against the corrosion of copper. Electrochemical methods ( electrochemical impedance spectroscopy and potentiodynamic polarization), and piezoelectric method (quartz crystal microbalance with impedance analysis (EQCM-I) were applied to study the corrosion protection performance of the inhibitor. Electrochemical measurements have indicated favorable corrosion inhibition performance of [CNic]Br. The corrosion inhibition efficiency increases with the increase of inhibitor concentration, at a [CNic]Br concentration of 10 M the efficiency reaches 93 %. The inhibitor adsorption slightly differed from the ideal Langmuir adsorption isotherm. [CNic]Br can be considered to be a mixed-type inhibitor. The inhibition efficiency was found to be time-dependent. In the presence of the highest 10 M inhibitor concentration the formation of the maximum protective effect of the inhibitor layer takes several hours, the maximum value of polarization resistance was 8.5 kΩ cm after 5 h. The copper dissolution and the inhibitor adsorption were also monitored by real-time changes in mass and viscoelasticity determined by QCM-I. It was obtained that the inhibitor adsorption on the copper surface leads to a decrease in copper dissolution and an increase in viscoelasticity. The layer on the copper surface becomes softer due to the complex between the inhibitor and the corrosion products on the surface.

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  • The exploration of efficient and safe chemodynamic therapy (CDT)-based cancer treatment is expected but still faces challenges. Herein, a kind of multifunctional nanomicelles was constructed for CDT, combined with biocompatible polysaccharides as nanocarriers, pH responsiveness and active targeting of P-selectin overexpressed tumors. The P-selectin-targeted ligand, polyguluronate sulfate (PGS), complexed with copper peroxide to form PGS-Cu nanomicelles by electrostatic interactions. Under acidic conditions, PGS-Cu nanomicelles released copper ions with HO and were able to produce •OH by Fenton-like reaction. In vitro data demonstrated PGS-Cu nanomicelles had high selectivity targeting P-selectin over-expressed cancer cells and induced cell death via CDT. In vivo evaluation showed PGS-Cu nanomicelles were enriched in tumor tissues and significantly inhibited tumor growth. This study identified that PGS-Cu nanomicelles could be a highly effective strategy for CDT cancer treatment.

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  • Single-crystal X-ray diffraction and electron paramagnetic resonance (EPR) spectroscopic experiments, complemented by quantum chemical DFT calculations, were carried out on the copper-doped metal-organic hybrid and Tutton salt analogue zinc creatininium sulfate to determine its crystal structure, to characterize the electronic structure of the doped Cu(II) binding site, and to propose a pathway for an excited-state, proton-coupled electron transfer (PCET) process in UV-exposed crystals. The crystal structure is isomorphous to that of cadmium creatininium sulfate, which has the transition ion, not in direct coordination with the creatinine, but forming a hexahydrate complex, which is bridged to a creatininium through an intervening sulfate ion. The EPR (2.446, 2.112, 2.082) and copper hyperfine (: -327, -59.6, 10.8 MHz) tensor parameters are consistent with doped copper replacing host zinc in the metal-hexahydrate complex. These parameters are similar to those observed for copper hexahydrate in doped Tutton salt systems at low temperature, where the unpaired electron occupies mainly the copper 3 orbital. At room temperature in the Tutton systems, vibration couplings stemming from a dynamic Jahn-Teller effect cause tensor averaging which results in a reduction in their maximum -tensor and hyperfine tensor values. However, like for the doped isomorphous Cd creatinine crystal, the Cu(II) EPR exhibits little, or no room temperature averaging compared to its low temperature pattern. Samples exposed to 254 nm UV light generate a carbon-centered free radical species, characterized by an isotropic g-tensor ( = 2.0029) and an alpha-proton hyperfine coupling (-24 -14 +4 G). These parameters identify it as a creatinine radical cation formed by the oxidative release of one of its C2 methylene hydrogens. DFT calculations confirm the unpaired electronic structures of both the Cu(II) site and free radical. The growth in radical concentration with an increase in the UV exposure time coincides with a decrease in the copper EPR signal, indicating a coupled light-induced oxidation reduction process. A comparison of the crystal structure with the EPR parameters and DFT results provides evidence for a UV-induced PCET.

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  • This study aimed to investigate the effects of replacing inorganic trace minerals (ITM) with organic trace minerals (OTM) on growth performance, body composition, gut histomorphometry, digestive enzyme activity, apparent digestibility coefficients (ADC), and mineral balance in juvenile Nile tilapia, . Fish ( = 432; 2.5 ± 0.5 g) were randomly distributed into four groups with four replicates each (27 fish per replicate). A control diet (gross 15.2 MJ gross energy kg; 367.3 g crude protein kg) was elaborated to meet the dietary requirements of zinc (Zn), manganese (Mn), and copper (Cu) using ITM in the sulfate form (ITM100). From the control diet, three diets were elaborated using OTM to supply 100% (OTM100), 75% (OTM75), and 50% (OTM50) of Zn, Mn, and Cu ITM of the control diet, respectively, supplied in the glycinate form. Fish were hand-fed six times daily for 8 weeks. Growth performance was not changed by dietary treatments. Fish fed on the diet OTM50 showed higher whole-body and vertebrae ash contents and higher whole-body calcium (Ca), Zn, and iron (Fe) retention than those fed on the control diet. The activity of digestive enzymes and the ADC of energy and nutrients, including Zn, Mn, and Cu, were similar in fish fed on diets OTM50 and ITM100. A reduction in Zn (-39.8%), Mn (-11.1%), and Cu (-14.0%) loss was observed in fish fed on the diet OTM50 than in fish fed diet ITM100. The dietary treatments did not affect the gut histomorphometry. In conclusion, the inclusion of OTM in Nile tilapia's diets represents a promising strategy to reduce 50% of ITM sources by utilizing Zn, Mn, and Cu OTM as glycinates without detrimental effects on growth performance, nutrient utilization, and gut function. These results additionally reinforce the environmental benefits of using OTM for precise mineral nutrition in aquaculture.

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