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Lipase-catalyzed organic reactions have been widely practiced in the past three decades. Especially interesting are insoluble/immobilized forms due to providing a possibility of facile use and recyclability, thus reducing process costs, and making the procedure more environmentally friendly. Carbon-based supports have been extensively exploited for this purpose, because of neutral and biodegradable nature and thermal and chemical stability. Their high specific surface area, characteristic surface morphology and lower mass transfer resistances play a vital role in the performance of the attached enzyme. This review paper presents an overview of the main aspects of lipase immobilized on multi-walled carbon nanotubes (MWCNTs). Moreover, different immobilization strategies to achieve a biocatalyst with improved performances are discussed. Furthermore, as lipases are considered to have high commercial worth for synthesis of valuable organic molecules, the second part of the paper is dedicated to the overview of the most important industrial sectors in which these nanobiocatalysts have been used. In specific, applications in biodiesel production, flavour ester synthesis and racemization are summarized., Lipaze su poslednjih decenija široko rasprostanjeni katalizatoriu raznovrsnim organskim reakcijama. Posebno su interesantne u imobilisanom/nerastvornom obliku jer je na ovaj način olakšana njihova upotreba uz mogućnost recikliranja i ponovne upotrebe čime se smanjuju troškovi samog procesa i postupak je ekološki prihvatljiviji. Kao nosači za vezivanje nanomaterijali na bazi ugljenika, posebno ugljenične nanocevi, su našli primenu zbog svojih izuzetnih fizičkih, mehaničkih i hemijskih svojstava. Njihova velika specifična površina, karakteristična površinska morfologija i smanjen otpor prenosu mase igraju vitalnu ulogu u performansama vezanog enzima. Ovaj pregledni rad predstavlja prikaz glavnih aspekata lipaze imobilisane na višeslojne ugljenične nanocevi i različitih strategija imobilizacije za dobijanje biokatalizatora sa poboljšanim svojstvima. Takođe, kako su lipaze enzimi od velikog komercijalnog značaja za organsku sintezu i primenu u biotehnologiji, drugi deo rada posvećen je pregledu najvažnijih industrijskih sektora u kojima su ovi nanobiokatalizatori našli primenu. Shodno tome, dat je pregled proizvodnje biodizela, mirisnih estara i racemizacije

Lipase-catalyzed organic reactions have been widely practiced in the past three decades. Especially interesting are insoluble/immobilized forms due to providing a possibility of facile use and recyclability, thus reducing process costs, and making the procedure more environmentally friendly. Carbon-based supports have been extensively exploited for this purpose, because of neutral and biodegradable nature and thermal and chemical stability. Their high specific surface area, characteristic surface morphology and lower mass transfer resistances play a vital role in the performance of the attached enzyme. This review paper presents an overview of the main aspects of lipase immobilized on multi-walled carbon nanotubes (MWCNTs). Moreover, different immobilization strategies to achieve a biocatalyst with improved performances are discussed. Furthermore, as lipases are considered to have high commercial worth for synthesis of valuable organic molecules, the second part of the paper is dedicated to the overview of the most important industrial sectors in which these nanobiocatalysts have been used. In specific, applications in biodiesel production, flavour ester synthesis and racemization are summarized., Lipaze su poslednjih decenija široko rasprostanjeni katalizatoriu raznovrsnim organskim reakcijama. Posebno su interesantne u imobilisanom/nerastvornom obliku jer je na ovaj način olakšana njihova upotreba uz mogućnost recikliranja i ponovne upotrebe čime se smanjuju troškovi samog procesa i postupak je ekološki prihvatljiviji. Kao nosači za vezivanje nanomaterijali na bazi ugljenika, posebno ugljenične nanocevi, su našli primenu zbog svojih izuzetnih fizičkih, mehaničkih i hemijskih svojstava. Njihova velika specifična površina, karakteristična površinska morfologija i smanjen otpor prenosu mase igraju vitalnu ulogu u performansama vezanog enzima. Ovaj pregledni rad predstavlja prikaz glavnih aspekata lipaze imobilisane na višeslojne ugljenične nanocevi i različitih strategija imobilizacije za dobijanje biokatalizatora sa poboljšanim svojstvima. Takođe, kako su lipaze enzimi od velikog komercijalnog značaja za organsku sintezu i primenu u biotehnologiji, drugi deo rada posvećen je pregledu najvažnijih industrijskih sektora u kojima su ovi nanobiokatalizatori našli primenu. Shodno tome, dat je pregled proizvodnje biodizela, mirisnih estara i racemizacije

The reduction of water pollution represents one of the priority topics of the EU’s goal to achieve climate neutrality by 2050. Herby textile industry is focused on developments in numerous environmental and social issues, including high emissions, high water and/or energy consumption and heavy pollution [1]. Coloured effluents from this industry disposed into natural ecosystems are responsible for about 20% of global clean water pollution [2]. The European Union aims to reduce textile waste and increase the life cycle and recycling of textiles as part of the plan to achieve a circular economy by 2050 by sustainable products and empowering consumers to participate in the green transition [2]. One of the main research topics connecting textile industry and waste water reduction is found in synthesis of eco-friendly dyes which are superior to their natural analogues due to the excellent dyeing capabilities and colour fastness properties. Among these, azo pyridine dyes gained attention for the simplicity of their preparation, good colour fastness, high tinctorial strength, thermal and optical stability [3]. Traditionally, applied as disperse dyes, they have low water solubility and are used for colouring mostly synthetic fibres. Recent findings showed that the introduction of the pyridinium ring into pyridone molecule resulted in enhanced water solubility of the dyes and improved affinity towards various natural and synthetic fibres, especially wool and cellulose diacetate fibres [4]. For the purpose of addressing environmental issues in the textile industry, in this work, two pyridinium-based azo pyridone dyes with improved solubility and affinity towards different fibres, are used for dyeing wool fabric. The results show that the same dyebath can be efficiently used multiple times, therefore reducing waste in the water while securing the optimizing dying. The obtained fabrics from different cycles are further characterized by K/S values while the residue of the dye in

The quest for sustainable biomaterials with excellent biocompatibility and tailorableproperties has put polyhydroxyalkanoates (PHAs) into the research spotlight. However, high productioncosts and the lack of bioactivity limit their market penetration. To address this, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was combined with a bacterial pigment with stronganticancer activity, prodigiosin (PG), to obtain functionally enhanced PHBV-based biomaterials. Thesamples were produced in the form of films 115.6–118.8 m in thickness using the solvent castingmethod. The effects of PG incorporation on the physical properties (morphology, biopolymer crystallinityand thermal stability) and functionality of the obtained biomaterials were investigated. PGhas acted as a nucleating agent, in turn affecting the degree of crystallinity, thermal stability andmorphology of the films. All samples with PG had a more organized internal structure and highermelting and degradation temperatures. The calculated degree of crystallinity of the PHBV copolymerwas 53%, while the PG1, PG3 and PG3 films had values of 64.0%, 63.9% and 69.2%, respectively.Cytotoxicity studies have shown the excellent anticancer activity of films against HCT116 (coloncancer) cells, thus advancing PHBV biomedical application potential.

During a fire, passive fire protection systems are designed to prevent the spread of flames, smoke, and toxic gases. The new fire-retardant (FR) material, used for passive fire protection, is created by combining copolymers (VC–co–VAc) (Slovinyl KV 173) and PVC K70 with expanded graphite and plasticizers/modifiers such as diisononyl phthalate-DINP, diisononyl terephthalate-DINTP, dioctyl adipate-DOA, as well as plasticizers that are synthesized based on tertiary recycling of waste poly(ethylene terephthalate) (PET), 1-hexadecene, azodicarbonamide (ADC), tri(p-cresyl phosphate), epoxidized soybean oil (ESO) and acrylate emulsion (DH50, Ecrylic, or Flexryl, etc.). The obtained material's morphology was examined using an emission scanning electron microscope (FESEM) field. Tensile testing was used to determine the mechanical properties of the obtained samples, as well as Shore A hardness and toughness using the Charpy impact test. All samples obtained were tested according to non-flammability standards. To conform to the new trend of "green economy," the development of novel eco-friendly FRs with improved thermal and mechanical properties will include careful consideration of environmental protection and sustainable development.

A series of twelve novel hybrids of cinnamic acid and thiocarbohydrazones were designed, synthesized in high yield using a simple coupling strategy via acid chlorides, and evaluated for their impact against Mycobacterium tuberculosis (Mtb) and cancer cells survival. Among them, compound 3 demonstrated strong anti-Mtb activity by reducing bacilli survival for>90 % in all three treated Mtb isolates, whereas isoniazid and rifampicin did not. Moreover, compound 3 didn't affect vitality of HepG-2 cells, implying on advantageous hepatotoxicity profile compared to current therapeutic options for tuberculosis. Compounds 2a and 3b displayed as strong inducers of apoptosis in A549 cells, both activating intrinsic caspase pathway and cell cycle arrest at the G0/ G1 phase. Subsequent analyses disclosed differences in their activities, where 3b has ability to induce production of mitochondrial superoxide anions, while 2a significantly inhibited cellular mobility. More importantly, 3b considerably affected viability of HepG-2 and HaCaT cells, whereas 2a had moderate impact only on the later. Molecular modeling studies indicated high permeability and good absorption through the human intestine, and moderate aqueous solubility with poor blood-brain barrier permeability. In summary, our results reveal that novel compounds 3 and 2a represent promising agents for tuberculosis and cancer treatment, respectively, indicating that fur-ther investigation needs to be performed to clarify the mechanisms of their anti-Mtb and anticancer activity. (c) 2021 The Authors. Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Management of waste polymers (polyethylene - PE and polypropylene - PP) represents one of the major obstacles in the field of environmental protection, which demands a most efficient and eco-friendly technological solution. Due to the high use of various plastic materials, the amount of landfilled or dissipated plastic waste is continuously growing. Therefore, this paper examines the possibilities of recycling these polymers, alongside obtaining granules of similar or advanced physico-mechanical characteristics to the commercially available ones. The applied technology consists of several consecutive processes (collecting, grinding, washing and extruding) where the obtained materials can later be incorporated into widely applicable products, such as foils, bin liners, bags, among others. In this way, high-quality products with great market potential are obtained, which will consequently contribute to lower extraction and less depletion of natural resources. Thus major problems may be solved optimally, consolidating the efficiency of improved eco-friendly technologies which is in line with environmental protection and sustainable waste management.

The aim of this paper is to investigate the application of modified lignin-based adsorbent for successful removal of dichromate ions and sodium diclofenac (DCF) from aqueous solutions by adsorption. Modification of lignin-based adsorbent (LBA) was performed by inverse suspension copolymerization with branched poly (ethylene-imine) using epichlorohydrin as a crosslinker. After that, the functionalization of LBA was performed by chemical binding of amino modified nanoparticles of manganese (IV) oxide, in order to improve the adsorption properties. Characterization of LBA-MnO2 microspheres was performed using FT-IR spectrometer, Scanning electron microscopy, BET/BJH analysis. The adsorption process was performed in a batch adsorption system. The results were obtained with the help of kinetic and corresponding equilibrium adsorption isotherms. The maximum adsorption capacity for the removal of Cr2O7 2- ions and DCF was obtained using the Langmuir model and amounts to 88.4 mg g-1 and 52.8 mg g-1 at 45 °C, respectively. Adsorption kinetics was described using a second-order pseudo model. Based on thermodynamic parameters, it was concluded that the adsorption process is an endothermic and spontaneous. Based on the obtained results, LBA-MnO2 material possess very good adsorption properties.

During a fire, passive fire protection systems are designed to prevent the spread of flames, smoke, and toxic gases. The new fire-retardant (FR) material, used for passive fire protection, is created by combining copolymers (VC-co-VAc) (Slovinyl KV 173) and PVC K70 with expanded graphite and plasticizers/modifiers such as diisononyl phthalate - DINP, diisononyl terephthalate - DINTP, dioctyl adipate - DOA, as well as plasticizers that are synthesized based on tertiary recycling of waste poly(ethylene terephthalate) (PET), 1-hexadecene, azodicarbonamide (ADC), tri(p-cresyl phosphate), epoxidized soybean oil (ESO) and acrylate emulsion (DH50, Ecrylic, or Flexryl, etc.). The obtained material's morphology was examined using an emission scanning electron microscope (FESEM) field. Tensile testing was used to determine the mechanical properties of the obtained samples, as well as Shore A hardness and toughness using the Charpy impact test. All samples obtained were tested according to non-flammability standards. To conform to the new trend of "green economy," the development of novel eco-friendly FRs with improved thermal and mechanical properties will include careful consideration of environmental protection and sustainable development.

The specific objectives of the presented study were related to the optimization of the production process of N-alkyl-, N,N-dialkyl-, and N-cycloalkyl-O-isobutyl thiocarbamate; trial industrial production of N-ethyl-O-isobutyl thiocarbamate; and the evaluation of flotation efficiency of N-ethyl-O-isobutyl thiocarbamate using a real ore sample. The optimization of thiocarbamate syntheses were performed by varying the molar ratio of isobutyl alcohol, carbon disulfide, potassium hydroxide, reaction time, and reaction temperature. In the first step, one-pot reaction took place to produce alkyl xanthate and was followed with chlorination to give alkyl chloroformate (O-alkyl carbonochloridothioate); finally, thiocarbamates were obtained by the reaction with corresponding amines. N-alkyl-O-ethyl thiocarbamate was synthesized as a comparative flotation agent. The structure of the synthesized compounds was confirmed by IR, H-1 and C-13 NMR, and MS instrumental methods, and the purity was determined by gas chromatographic method and elemental analysis. The optimized methods gave high-purity products in a significant yield that was also confirmed by semi-industrial production of N-ethyl-O-isobutyl thiocarbamate. The optimized thiocarbamate synthesis, without isolation of intermediates, is of great importance from the aspect of green technologies. Flotation efficiency test results, using real copper and zinc ores, showed the highest activity of N-ethyl-O-isobutyl thiocarbamate. The optimal one-pot thiocarbamate synthesis provides a simple procedure with a high conversion degree, and, thus, offers valuable technology applicable at the industrial scale.

Photocatalytic degradation of the carbamate insecticide methomyl and its commercial product Lannate-90 in aqueous suspension of TiO2 and ZnO using an Osram ultra-vitalux lamp (315-400 nm) was investigated. The objective of the investigation was to study and compare the rates of photochemical degradation of the pure active compound and its formulated product in order to find out the impact of inert ingredients on degradation processes. The photo-chemical degradation of pure methomyl was found to be slower than the degradation of its commercial product Lannate-90. Photodegradation was investigated by UV-Vis spectrometry and HPLC, while mineralization was monitored using IC and TOC analyses. Light absorption capabilities of catalysts were characterized by ultraviolet-visible diffuse reflectance spectroscopy method, while the stability of catalysts was studied by infrared analyses. Degradation products of methomyl and its formulated product were identified by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) results and tentative photodegradation pathways were proposed.

In this work, the optimization of synthesis of terpolymer monolith based on glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA) and additional cross-linkers: trimethylolpropanetriacrylate (TMPTA) or triethylene glycol dimethacrylate (TEGDMA) was performed. Moreover, novel vinyl functionalized cross-linkable polymers: ethanolamine (EA)/methacryloyl (MAC) modified poly (methyl methacrylate) (PMMA), and hydrolyzed poly (ethylene-co-vinyl acetate) copolymer (EVOH) modified with MAC either directly or via ethyl malonyl chloride/EA bridging group (m-EVA) were used as cross-linkable polymer to improve mechanical/elastic properties of the obtained monoliths. Optimization procedure, performed applying response surface methodology (RSM), was focused on the production of materials with improved dimensional stability/integrity and porosity with abundance of epoxide groups capable for immobilization of lipase from Candida rugosa (CRL). Structural characterization of the synthesized monoliths was determined using FTIR, Raman and H-1 NMR spectroscopies, while morphology/porosity was determined by SEM technique and image analysis; and mechanical properties by diametral compression testing. The most potential monolith containing m-EVA polymeric cross-linker, i.e. GMA/EGDMA/TEGDMA/m-EVA monolith, was used as CRL carrier in a two-step immobilization process. Enzyme loading and the activity of obtained preparations for various initial enzyme concentrations were monitored after 4 and 48 h of immobilization. The resulting catalysts show high potency in biocatalytic reactions with the highest percentage of retained initial lipase activity of 64.5%.

Conformational stability of various 5-substituted orotic acid derivatives was studied by applying linear free energy relationships (LFER) to the C-13 NMR chemical shifts. The correlation analysis for the substituent-induced chemical shifts (SCS) with inductive (rI), and various resonance (rR) parameters were carried out through Single Substituent Parameter (SSP) and Dual Substituent Parameter (DSP) methods, and multiple regression analysis. Good Hammett correlations for all carbons were obtained, while electrophilic substituent constants better fitted for C2 carbon with electron-donor substituents. Conformational analysis of various derivatives using RB3LYP/6-311 ++G (3df,3dp) DFT method, together with C-13 NMR data suggests that most of the substituted orotic acid derivatives exist in planar conformation, except nitro and alkyl substituted derivatives. Internal rotation of carboxylic group showed significant impact on the extent of conjugative interaction making syn conformation more stable in all the derivatives studied. Further, of all 5-substituted orotic acid derivatives, diketo form proved to be the most stable form compared to zwitterionic and enol tautomeric forms. Optimized geometries and transmission effects of particular substituent through well-defined p-resonance units suggest that these units behave as isolated as well as conjugated fragments, depending on the type of substituent.

The substituent and solvent effect on intramolecular charge transfer (ICT) in 5-aryli dene-3-methyl-2,4-thiazolidinediones (series 1) and 5-arylidene-3-phenyl-2,4-thiazolidinediones (series 2) was studied by using experimental and theoretical methodology. The effect of specific and non-specific solvent-solute interactions on the UV-vis absorption maxima shifts was evaluated by using the Kamlet-Taft and Catalan solvent parameter sets. Linear free energy relationships (LFERs) have been applied to the UV-vis and C-13 NMR data by using SSP (single substituent parameter) and DSP (dual substituent parameters). Comparative LFER analysis of 10 styrenic series was performed in order to distinguish contribution of structural and electronic substituent effect on extent of p-polarization in a side chain (vinyl) group. Furthermore, the experimental findings were interpreted with the aid of ab initio MP2 and time-dependent density functional (TD-DFT) methods. TD-DFT calculations are performed to quantify the efficiency of intramolecular charge transfer (ICT) allowing us to define the charge-transfer distance (DCT), amount of transferred charge (QCT), and difference of dipole moments between the ground and excited states (mu CT). It was found that both substituents and solvents influence electron density shift, i.e. extent of conjugation, and affect intramolecular charge transfer character in the course of excitation.

Derivati izatina su se u novije vreme pokazali kao jedinjenja korisna u farmakologiji, jer ispoljavaju širok spektar dejstava kao sto su antivirusna, antitumorna, antibakterijska, antituberkulozna, antigljivična, antikonvulzivna. Reč je o jedinjenjima koja nastaju reakcijom izatina i primarnih amina i spadaju u grupu Šifovih (Schiff) baza. Kao deo serije istraživanja koje se bavi derivatima izatina, sintetisani su i njihovi kompleksi sa metalima. Ispitana je njihova antimikrobna aktivnost, pomoću bujon - mikrodilucione metode, na kojoj se može zasnovati i mogućnost njihove primene., The isatin derivatives have recently shown the potential to be used in pharmaclogy because of their activities such as antiviral, anticancer, antibacterial, antituberculosis, antifungal and anticonvulsive. These compounds belong to the group of Schiff bases and they are synthesized by the reaction of isatin and primary amines. As a part of the series of investigation that deals with the isatin derivatives, their complexes with metals were synthesized. Their antimicrobial activity was examined using the broth micro-dilution method, which could provide the ground for the application of these compounds.