Marina Nisnevitch - Academia.edu (original) (raw)

Papers by Marina Nisnevitch

Biosensors

L-Lactate is an indicator of food quality, so its monitoring is essential. Enzymes of L-Lactate m... more L-Lactate is an indicator of food quality, so its monitoring is essential. Enzymes of L-Lactate metabolism are promising tools for this aim. We describe here some highly sensitive biosensors for L-Lactate determination which were developed using flavocytochrome b2 (Fcb2) as a bio-recognition element, and electroactive nanoparticles (NPs) for enzyme immobilization. The enzyme was isolated from cells of the thermotolerant yeast Ogataea polymorpha. The possibility of direct electron transfer from the reduced form of Fcb2 to graphite electrodes has been confirmed, and the amplification of the electrochemical communication between the immobilized Fcb2 and the electrode surface was demonstrated to be achieved using redox nanomediators, both bound and freely diffusing. The fabricated biosensors exhibited high sensitivity (up to 1436 A·M−1·m−2), fast responses, and low limits of detection. One of the most effective biosensors, which contained co-immobilized Fcb2 and the hexacyanoferrate of ...

Applied Sciences

The broad definition of the term biosensing relates to practically all processes of molecular rec... more The broad definition of the term biosensing relates to practically all processes of molecular recognition [...]

Biosensors

Laccase is a copper-containing enzyme that does not require hydrogen peroxide as a co-substrate o... more Laccase is a copper-containing enzyme that does not require hydrogen peroxide as a co-substrate or additional cofactors for an enzymatic reaction. Nanomaterials of various chemical structures are usually applied to the construction of enzyme-based biosensors. Metals, metal oxides, semiconductors, and composite NPs perform various functions in electrochemical transformation schemes as a platform for the enzyme immobilization, a mediator of an electron transfer, and a signal amplifier. We describe here the development of amperometric biosensors (ABSs) based on laccase and redox-active micro/nanoparticles (hereafter—NPs), which were immobilized on a graphite electrode (GE). For this purpose, we isolated a highly purified enzyme from the fungus Trametes zonatus, and then synthesized bi- and trimetallic NPs of noble and transition metals, as well as hexacyanoferrates (HCF) of noble metals; these were layered onto the surfaces of GEs. The electroactivity of many of the NPs immobilized on ...

Biomedicines

Phlomis viscosa Poiret (an evergreen shrub) represents a valuable source of medicinal compounds. ... more Phlomis viscosa Poiret (an evergreen shrub) represents a valuable source of medicinal compounds. In this study, we discovered compounds with antimicrobial and antiviral properties. The aim of this study was to identify compounds of P. viscosa and estimate the antimicrobial and antiviral activity of its phytochemicals. The volatile compounds were identified using gas chromatography/mass spectrometry (GC/MS) analysis. For the identification of nonvolatile components of the extracts, high-performance liquid chromatography (HPLC), liquid chromatography–electrospray ionization-mass spectrometry (LC-ESI-MS) and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) were applied. Quercetin 3-O-rutinoside and hesperidin caused a significant decrease in the bacterial concentration of Agrobacterium tumefaciens, Xylella fastidiosa and Pseudomonas syringae (p < 0.001). The growth of drug-resistant microorganisms (Escherichia coli, Klebsiella pneumoniae, A...

Energies

Biofuel is considered one of the most viable alternatives to fossil fuels derived from the dwindl... more Biofuel is considered one of the most viable alternatives to fossil fuels derived from the dwindling petroleum resources that damage the environment. Bioethanol could be manufactured from agricultural wastes, thus providing inexpensive natural resources. Several strategies have been utilized to convert lignocellulosic hydrolysate to bioethanol with various suspended microorganisms. In this study, we alternatively propose to encapsulate these microorganisms in bioreactor setups. An immobilized cell system can provide resistance to the inhibitors present in hydrolysates, enhance productivity, facilitate the separation process, and improve microorganism recycling. Herein, we developed a continuous bioethanol production process by encapsulating three types of micro-organisms: T. reesei, S. cerevisiae, and P. stipitis. These microorganisms were encapsulated in SBP (“Small Bioreactor Platform”) capsules and tested for their viability post encapsulation, biological activity, and bioethanol...

Charcoal production is still considered a polluting industry with a certain impact on global clim... more Charcoal production is still considered a polluting industry with a certain impact on global climate change. This traditional practice along the Eastern Mediterranean Sea shoreline exists since the iron age and was industrialized during the Ottoman Empire period, for fueling the Hijaz train engines. The charcoal production continued long after the Hijaz trainline ceased and gradually increased in magnitude, becoming a major environmental and health issue in the last couple of decades. In parallel to the regulatory actions aimed at stopping air pollution, the development of a new type of ecological charcoal production system involved cooperation between Palestinian charcoal manufacturers and Israeli researchers. This combined effort has led to the termination of air pollution through the implementation of the new system and the transformation of the land previously used for charcoal production into farming.

International Journal of Molecular Sciences, 2022

Photosensitizers (PSs) are known as powerful antibacterial agents that are activated by direct ex... more Photosensitizers (PSs) are known as powerful antibacterial agents that are activated by direct exposure to visible light. PSs can be noncovalently entrapped into the silica gel network for their controlled release into a contaminated area. The immobilization of PS-containing gel matrices on a polymer support expands their possible applications, such as antibacterial surfaces and coatings, which can be used for the disinfection of liquids. In the current study, we report the use of Rose Bengal (RB) incorporated into organically modified silica matrices (RB@ORMOSIL matrices) by the sol-gel technique. The RB matrices exhibit high activity against Gram-positive and Gram-negative bacteria under illumination by white light. The amount and timing of solidifier addition to the matrix affected the interaction of the latter with the RB, which in turn could affect the antibacterial activity of RB. The most active specimen against both Gram-positive and Gram-negative bacterial cells was the RB6...

Processes, 2021

Current strategies of combating bacterial infections are limited and involve the use of antibioti... more Current strategies of combating bacterial infections are limited and involve the use of antibiotics and preservatives. Each of these agents has generally inadequate efficacy and a number of serious adverse effects. Thus, there is an urgent need for new antimicrobial drugs and food preservatives with higher efficacy and lower toxicity. Edible plants have been used in medicine since ancient times and are well known for their successful antimicrobial activity. Often photosensitizers are present in many edible plants; they could be a promising source for a new generation of drugs and food preservatives. The use of photodynamic therapy allows enhancement of antimicrobial properties in plant photosensitizers. The purpose of this review is to present the verified data on the antimicrobial activities of photodynamic phytochemicals in edible species of the world’s flora, including the various mechanisms of their actions.

The 1st International Electronic Conference on Biosensors, 2020

Nanozymes (NZs) are catalytically active nanomaterials that have enzyme-like activity but possess... more Nanozymes (NZs) are catalytically active nanomaterials that have enzyme-like activity but possess increased stability and greater availability due to the fact of their simpler preparation technologies. Nanozymes as nanoscale artificial enzymes demonstrate various catalytic specificities as oxidoreductases, such as peroxidase, catalase, laccase, and others as well as hydrolases, proteases, endonucleases, DNA-ases, NO synthases, etc. A broad variety of NZs exhibits dual-or multienzyme mimetic activity. Nanozymes as stable, low-cost mimetics of natural enzymes have a high potential for application in different branches of biotechnology including scientific investigations, industry, and ecology. Nanozymes can be applied in medicine as diagnostic tools and components of therapeutic drugs. Since NZs have high catalytic activity and chemical and biological stability, they are very promising in the construction of biosensors and biofuel cells. For these reasons, the search for simple methods of synthesis and characterization of different NZs is a very important and real problem. The "green" synthesis of Prussian blue analogous as peroxidase-like NZs using oxido-reductases is described in this study. The obtained green-synthesized hexacyanoferrates (gHCFs) of transition metals were characterized by structure, size, composition, catalytic properties, electro-mediator activities, and substrate specificity. Copper hexacyanoferrate (gCuHCF) was studied in more detail. When immobilized on a graphite electrode (GE), gCuHCF under special conditions of pH and tension gave amperometric signals on hydrogen peroxide and can be used as a peroxidase mimetic in oxidase-based biosensors. Under other conditions, gCuHCF/GE reacts to other analytes. We propose that gHCFs of transition metals synthesized via enzymes may become prospect platforms for the construction of multi-functional amperometric (bio)sensors.

Quality Control in the Beverage Industry, 2019

Abstract The fermented foods and beverages industry needs effective manufacturing technologies an... more Abstract The fermented foods and beverages industry needs effective manufacturing technologies and reliable methods of analysis in order to ensure the safety and high quality of the final products. The following substances must be controlled in the wine industry: basic components (ethanol, sugar, and glycerol), aromatic volatile organic chemicals, dangerous products (impurities and carcinogenic metabolites of the beverage process) as well as toxic ions of heavy and transition metals. A wide range of traditional and advanced analytical methods is used in wine science and wineries for monitoring organic and inorganic chemicals in wines. However, they all have certain disadvantages. Well-known physicochemical methods usually lack precision, sensitivity, and selectivity. Modern high-throughput approaches require special skills, are time-consuming, expensive, and often also have low selectivity. This situation necessitates further development of highly selective and sensitive methods for monitoring important analytes in the winemaking and food industries. Simple and low-cost enzymatic approaches can be promising for monitoring chemicals (enzymes substrates and their cofactors) in routine assays, not only for the industrial giants, but also for small wineries. This chapter includes a description of modern quantitative assay methods for important components of wines and novel highly selective enzymatic approaches, as well as the authors’ research results, conclusions, and future prospects.

Copyright © 2014 Sasi Sigawi et al. This is an open access article distributed under the Creative... more Copyright © 2014 Sasi Sigawi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Aliphatic amines, including methylamine, are air-pollutants, due to their intensive use in industry and the natural degradation of proteins, amino acids, and other nitrogen-containing compounds in biological samples. It is necessary to develop systems for removal ofmethylamine from the air, since airbornemethylamine has a negative effect on humanhealth.Theprimary amine oxidase (primary amine: oxygen oxidoreductase (deaminating) or amine oxidase, AMO; EC 1.4.3.21), a copper-containing enzyme from the thermotolerant yeast Hansenula polymorpha which was overexpressed in baker’s yeast Saccharomyces cerevisiae, was tested for its ability to oxidize airborne methylamine. A continuous fluidized bed bioreactor (CFBR) was designed to enable bioc...

Abstract: The photosensitizers Rose Bengal (RB) and methylene blue (MB), when immobilized in poly... more Abstract: The photosensitizers Rose Bengal (RB) and methylene blue (MB), when immobilized in polystyrene, were found to exhibit high antibacterial activity in a continuous regime. The photosensitizers were immobilized by dissolution in chloroform, together with polystyrene, with further evaporation of the solvent, yielding thin polymeric films. Shallow reservoirs, bottom-covered with these films, were used for constructing continuous-flow photoreactors for the eradication of Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli and wastewater bacteria under illumination with visible white light using a luminescent lamp at a 1.8 mW·cm−2 fluence rate. The bacterial concentration decreased by two to five orders of magnitude in separate reactors with either immobilized RB or MB, as well as in three reactors connected in series, which contained one of the photosensitizers. Bacterial eradication reached more than five orders of magnitude in two reactors connected in series, ...

New techniques in antimicrobial photodynamic therapy: scope of

Non-conventional Yeasts: from Basic Research to Application, 2019

Microbial enzymes have gained interest for their widespread use in industries and medicine due to... more Microbial enzymes have gained interest for their widespread use in industries and medicine due to their stability, catalytic activity, and low-cost production, compared to plant and animal analogues. Microbial enzymes are capable of degrading toxic chemical compounds of industrial and domestic wastes by degradation or via conversion to nontoxic products. Enzyme technology broadly involves production, isolation, purification, and use of enzymes in various industries (e.g., food, medicine, agriculture, chemicals, pharmacology). The development of simple technologies for obtaining highly purified novel enzymes is an actual task for biotechnology and enzymology. This chapter presents a review of the main achievements in the elaboration of modern techniques for obtaining recombinant and novel enzymes. The results of a series of the authors' investigations into the development of novel enzymatic approaches, including biosensors, for determination of practically important analytes are summarized. The described methods are related to isolation of highly purified yeast oxido-reductases: alcohol oxidase, flavocytochrome b 2 , glycerol dehydrogenase, and formaldehyde dehydrogenase. The enzymes were isolated from selected or recombinant yeast cells using the simple and effective technologies developed by the authors.

Applied Sciences, 2021

Nanozymes (NZs) are nanostructured artificial enzymes that mimic catalytic properties of natural ... more Nanozymes (NZs) are nanostructured artificial enzymes that mimic catalytic properties of natural enzymes. The NZs have essential advantages over natural enzymes, namely low preparation costs, stability, high surface area, self-assembling capability, size and composition-dependent activities, broad possibility for modification, and biocompatibility. NZs have wide potential practical applications as catalysts in biosensorics, fuel-cell technology, environmental biotechnology, and medicine. Most known NZs are mimetics of oxidoreductases or hydrolases. The present work aimed to obtain effective artificial peroxidase (PO)-like NZs (nanoPOs), to characterize them, and to estimate the prospects of their analytical application. NanoPOs were synthesized using a number of nanoparticles (NPs) of transition and noble metals and were screened for their catalytic activity in solution and on electrodes. The most effective nanoPOs were chosen as NZs and characterized by their catalytic activity. Ki...

Massive use of fossil fuels has led to an increase in the CO2 concentration in the atmosphere, an... more Massive use of fossil fuels has led to an increase in the CO2 concentration in the atmosphere, and this has caused global climate changes. In contradistinction, biofuels, which are produced from plant sources, and in particular biodiesel, do not affect the greenhouse gas balance. Conventional sources of biodiesel are agricultural crops, such as corn, soybean, canola, cotton, mustard, and palm. However, use of these crops for biodiesel leads to the depletion of global food resources. The aim of the present study was to develop a scheme for rapid and efficient production of biodiesel from brown grease, i.e. cooking oil waste, which has a high free fatty acids content. Biodiesel is produced by free fatty acid esterification and triglyceride trans-esterification [1]. These processes can be performed under thermal activation and classical homogeneous catalysis; however, this scheme cannot serve for production of biodiesel in a continuous regime [2]. The present research proposes performa...

Pathogens, 2021

Conventional methods of onychomycosis treatment are ineffective in some cases because the cure of... more Conventional methods of onychomycosis treatment are ineffective in some cases because the cure of onychomycosis very often depends on the patient’s individual response to the treatment; therefore, there is a crucial need to research and develop new methods of onychomycosis therapy. One of the most innovative treatments is photodynamic therapy (PDT) using photosensitizers (PSs). However, effective treatment depends on the correct choice of photosensitizer and substances that improve the characteristics of the final formulation. The aim of our work was to find an effective formulation for the treatment of onychomycosis. To achieve this goal, we tested the effect of three types of PSs, rose Bengal (RB), malachite green oxalate (MGO), and methylene blue (MB), on Candida albicans. The most effective PS was RB, and so the study was continued with Trichophyton rubrum. Additional comparative studies were carried out on substances included in the formulation (urea and thiourea), focusing on ...

Formaldehyde (FA) is a very toxic pollutant. FA in indoor air has a negative effect on human heal... more Formaldehyde (FA) is a very toxic pollutant. FA in indoor air has a negative effect on human health and should be removed by ventilation or by conversion to non-toxic products. The formaldehyde dehydrogenase (FdDH), a NADand glutathione-dependent enzyme from recombinant methylotrophic yeast Hansenula polymorpha, was tested for its ability to oxidize airborne FA. A continuous fluidized bed bioreactor was designed to enable a bioconversion of airborne FA by FdDH or by recombinant yeast cells immobilized in calcium alginate beads. The results demonstrated that such the bioreactor with immobilized FdDH provides 97-100% elimination of airborne FA and the bioreactor with immobilized cells eliminates 94-100% of

Biosensors, 2021

Prussian blue analogs (PBAs) are well-known artificial enzymes with peroxidase (PO)-like activity... more Prussian blue analogs (PBAs) are well-known artificial enzymes with peroxidase (PO)-like activity. PBAs have a high potential for applications in scientific investigations, industry, ecology and medicine. Being stable and both catalytically and electrochemically active, PBAs are promising in the construction of biosensors and biofuel cells. The “green” synthesis of PO-like PBAs using oxido-reductase flavocytochrome b2 is described in this study. When immobilized on graphite electrodes (GEs), the obtained green-synthesized PBAs or hexacyanoferrates (gHCFs) of transition and noble metals produced amperometric signals in response to H2O2. HCFs of copper, iron, palladium and other metals were synthesized and characterized by structure, size, catalytic properties and electro-mediator activities. The gCuHCF, as the most effective PO mimetic with a flower-like micro/nano superstructure, was used as an H2O2-sensitive platform for the development of a glucose oxidase (GO)-based biosensor. Th...

Polymers, 2020

Consumption of contaminated water may lead to dangerous and even fatal water-borne diseases. Disi... more Consumption of contaminated water may lead to dangerous and even fatal water-borne diseases. Disinfection of drinking water is the most effective solution for this problem. The most common water treatment methods are based on the use of toxic disinfectants. Composites of polymers with nanosized metals and their oxides may become a good alternative to the existing methods. Expanding the scope of our previous publication, copper, cuprous, and copper oxide nanoparticles were immobilized onto linear low-density polyethylene by a simple thermal adhesion method. The antibacterial efficiency of the immobilized nanoparticles was tested against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus in batch experiments and for the first time the efficiency of these composites is reported for continuous flow regime. Immobilized copper and cuprous oxide nanoparticles demonstrated a high ability to eradicate bacteria after 30 min. These composites showed no or very limited leach...

Biosensors

L-Lactate is an indicator of food quality, so its monitoring is essential. Enzymes of L-Lactate m... more L-Lactate is an indicator of food quality, so its monitoring is essential. Enzymes of L-Lactate metabolism are promising tools for this aim. We describe here some highly sensitive biosensors for L-Lactate determination which were developed using flavocytochrome b2 (Fcb2) as a bio-recognition element, and electroactive nanoparticles (NPs) for enzyme immobilization. The enzyme was isolated from cells of the thermotolerant yeast Ogataea polymorpha. The possibility of direct electron transfer from the reduced form of Fcb2 to graphite electrodes has been confirmed, and the amplification of the electrochemical communication between the immobilized Fcb2 and the electrode surface was demonstrated to be achieved using redox nanomediators, both bound and freely diffusing. The fabricated biosensors exhibited high sensitivity (up to 1436 A·M−1·m−2), fast responses, and low limits of detection. One of the most effective biosensors, which contained co-immobilized Fcb2 and the hexacyanoferrate of ...

Applied Sciences

The broad definition of the term biosensing relates to practically all processes of molecular rec... more The broad definition of the term biosensing relates to practically all processes of molecular recognition [...]

Biosensors

Laccase is a copper-containing enzyme that does not require hydrogen peroxide as a co-substrate o... more Laccase is a copper-containing enzyme that does not require hydrogen peroxide as a co-substrate or additional cofactors for an enzymatic reaction. Nanomaterials of various chemical structures are usually applied to the construction of enzyme-based biosensors. Metals, metal oxides, semiconductors, and composite NPs perform various functions in electrochemical transformation schemes as a platform for the enzyme immobilization, a mediator of an electron transfer, and a signal amplifier. We describe here the development of amperometric biosensors (ABSs) based on laccase and redox-active micro/nanoparticles (hereafter—NPs), which were immobilized on a graphite electrode (GE). For this purpose, we isolated a highly purified enzyme from the fungus Trametes zonatus, and then synthesized bi- and trimetallic NPs of noble and transition metals, as well as hexacyanoferrates (HCF) of noble metals; these were layered onto the surfaces of GEs. The electroactivity of many of the NPs immobilized on ...

Biomedicines

Phlomis viscosa Poiret (an evergreen shrub) represents a valuable source of medicinal compounds. ... more Phlomis viscosa Poiret (an evergreen shrub) represents a valuable source of medicinal compounds. In this study, we discovered compounds with antimicrobial and antiviral properties. The aim of this study was to identify compounds of P. viscosa and estimate the antimicrobial and antiviral activity of its phytochemicals. The volatile compounds were identified using gas chromatography/mass spectrometry (GC/MS) analysis. For the identification of nonvolatile components of the extracts, high-performance liquid chromatography (HPLC), liquid chromatography–electrospray ionization-mass spectrometry (LC-ESI-MS) and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) were applied. Quercetin 3-O-rutinoside and hesperidin caused a significant decrease in the bacterial concentration of Agrobacterium tumefaciens, Xylella fastidiosa and Pseudomonas syringae (p < 0.001). The growth of drug-resistant microorganisms (Escherichia coli, Klebsiella pneumoniae, A...

Energies

Biofuel is considered one of the most viable alternatives to fossil fuels derived from the dwindl... more Biofuel is considered one of the most viable alternatives to fossil fuels derived from the dwindling petroleum resources that damage the environment. Bioethanol could be manufactured from agricultural wastes, thus providing inexpensive natural resources. Several strategies have been utilized to convert lignocellulosic hydrolysate to bioethanol with various suspended microorganisms. In this study, we alternatively propose to encapsulate these microorganisms in bioreactor setups. An immobilized cell system can provide resistance to the inhibitors present in hydrolysates, enhance productivity, facilitate the separation process, and improve microorganism recycling. Herein, we developed a continuous bioethanol production process by encapsulating three types of micro-organisms: T. reesei, S. cerevisiae, and P. stipitis. These microorganisms were encapsulated in SBP (“Small Bioreactor Platform”) capsules and tested for their viability post encapsulation, biological activity, and bioethanol...

Charcoal production is still considered a polluting industry with a certain impact on global clim... more Charcoal production is still considered a polluting industry with a certain impact on global climate change. This traditional practice along the Eastern Mediterranean Sea shoreline exists since the iron age and was industrialized during the Ottoman Empire period, for fueling the Hijaz train engines. The charcoal production continued long after the Hijaz trainline ceased and gradually increased in magnitude, becoming a major environmental and health issue in the last couple of decades. In parallel to the regulatory actions aimed at stopping air pollution, the development of a new type of ecological charcoal production system involved cooperation between Palestinian charcoal manufacturers and Israeli researchers. This combined effort has led to the termination of air pollution through the implementation of the new system and the transformation of the land previously used for charcoal production into farming.

International Journal of Molecular Sciences, 2022

Photosensitizers (PSs) are known as powerful antibacterial agents that are activated by direct ex... more Photosensitizers (PSs) are known as powerful antibacterial agents that are activated by direct exposure to visible light. PSs can be noncovalently entrapped into the silica gel network for their controlled release into a contaminated area. The immobilization of PS-containing gel matrices on a polymer support expands their possible applications, such as antibacterial surfaces and coatings, which can be used for the disinfection of liquids. In the current study, we report the use of Rose Bengal (RB) incorporated into organically modified silica matrices (RB@ORMOSIL matrices) by the sol-gel technique. The RB matrices exhibit high activity against Gram-positive and Gram-negative bacteria under illumination by white light. The amount and timing of solidifier addition to the matrix affected the interaction of the latter with the RB, which in turn could affect the antibacterial activity of RB. The most active specimen against both Gram-positive and Gram-negative bacterial cells was the RB6...

Processes, 2021

Current strategies of combating bacterial infections are limited and involve the use of antibioti... more Current strategies of combating bacterial infections are limited and involve the use of antibiotics and preservatives. Each of these agents has generally inadequate efficacy and a number of serious adverse effects. Thus, there is an urgent need for new antimicrobial drugs and food preservatives with higher efficacy and lower toxicity. Edible plants have been used in medicine since ancient times and are well known for their successful antimicrobial activity. Often photosensitizers are present in many edible plants; they could be a promising source for a new generation of drugs and food preservatives. The use of photodynamic therapy allows enhancement of antimicrobial properties in plant photosensitizers. The purpose of this review is to present the verified data on the antimicrobial activities of photodynamic phytochemicals in edible species of the world’s flora, including the various mechanisms of their actions.

The 1st International Electronic Conference on Biosensors, 2020

Nanozymes (NZs) are catalytically active nanomaterials that have enzyme-like activity but possess... more Nanozymes (NZs) are catalytically active nanomaterials that have enzyme-like activity but possess increased stability and greater availability due to the fact of their simpler preparation technologies. Nanozymes as nanoscale artificial enzymes demonstrate various catalytic specificities as oxidoreductases, such as peroxidase, catalase, laccase, and others as well as hydrolases, proteases, endonucleases, DNA-ases, NO synthases, etc. A broad variety of NZs exhibits dual-or multienzyme mimetic activity. Nanozymes as stable, low-cost mimetics of natural enzymes have a high potential for application in different branches of biotechnology including scientific investigations, industry, and ecology. Nanozymes can be applied in medicine as diagnostic tools and components of therapeutic drugs. Since NZs have high catalytic activity and chemical and biological stability, they are very promising in the construction of biosensors and biofuel cells. For these reasons, the search for simple methods of synthesis and characterization of different NZs is a very important and real problem. The "green" synthesis of Prussian blue analogous as peroxidase-like NZs using oxido-reductases is described in this study. The obtained green-synthesized hexacyanoferrates (gHCFs) of transition metals were characterized by structure, size, composition, catalytic properties, electro-mediator activities, and substrate specificity. Copper hexacyanoferrate (gCuHCF) was studied in more detail. When immobilized on a graphite electrode (GE), gCuHCF under special conditions of pH and tension gave amperometric signals on hydrogen peroxide and can be used as a peroxidase mimetic in oxidase-based biosensors. Under other conditions, gCuHCF/GE reacts to other analytes. We propose that gHCFs of transition metals synthesized via enzymes may become prospect platforms for the construction of multi-functional amperometric (bio)sensors.

Quality Control in the Beverage Industry, 2019

Abstract The fermented foods and beverages industry needs effective manufacturing technologies an... more Abstract The fermented foods and beverages industry needs effective manufacturing technologies and reliable methods of analysis in order to ensure the safety and high quality of the final products. The following substances must be controlled in the wine industry: basic components (ethanol, sugar, and glycerol), aromatic volatile organic chemicals, dangerous products (impurities and carcinogenic metabolites of the beverage process) as well as toxic ions of heavy and transition metals. A wide range of traditional and advanced analytical methods is used in wine science and wineries for monitoring organic and inorganic chemicals in wines. However, they all have certain disadvantages. Well-known physicochemical methods usually lack precision, sensitivity, and selectivity. Modern high-throughput approaches require special skills, are time-consuming, expensive, and often also have low selectivity. This situation necessitates further development of highly selective and sensitive methods for monitoring important analytes in the winemaking and food industries. Simple and low-cost enzymatic approaches can be promising for monitoring chemicals (enzymes substrates and their cofactors) in routine assays, not only for the industrial giants, but also for small wineries. This chapter includes a description of modern quantitative assay methods for important components of wines and novel highly selective enzymatic approaches, as well as the authors’ research results, conclusions, and future prospects.

Copyright © 2014 Sasi Sigawi et al. This is an open access article distributed under the Creative... more Copyright © 2014 Sasi Sigawi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Aliphatic amines, including methylamine, are air-pollutants, due to their intensive use in industry and the natural degradation of proteins, amino acids, and other nitrogen-containing compounds in biological samples. It is necessary to develop systems for removal ofmethylamine from the air, since airbornemethylamine has a negative effect on humanhealth.Theprimary amine oxidase (primary amine: oxygen oxidoreductase (deaminating) or amine oxidase, AMO; EC 1.4.3.21), a copper-containing enzyme from the thermotolerant yeast Hansenula polymorpha which was overexpressed in baker’s yeast Saccharomyces cerevisiae, was tested for its ability to oxidize airborne methylamine. A continuous fluidized bed bioreactor (CFBR) was designed to enable bioc...

Abstract: The photosensitizers Rose Bengal (RB) and methylene blue (MB), when immobilized in poly... more Abstract: The photosensitizers Rose Bengal (RB) and methylene blue (MB), when immobilized in polystyrene, were found to exhibit high antibacterial activity in a continuous regime. The photosensitizers were immobilized by dissolution in chloroform, together with polystyrene, with further evaporation of the solvent, yielding thin polymeric films. Shallow reservoirs, bottom-covered with these films, were used for constructing continuous-flow photoreactors for the eradication of Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli and wastewater bacteria under illumination with visible white light using a luminescent lamp at a 1.8 mW·cm−2 fluence rate. The bacterial concentration decreased by two to five orders of magnitude in separate reactors with either immobilized RB or MB, as well as in three reactors connected in series, which contained one of the photosensitizers. Bacterial eradication reached more than five orders of magnitude in two reactors connected in series, ...

New techniques in antimicrobial photodynamic therapy: scope of

Non-conventional Yeasts: from Basic Research to Application, 2019

Microbial enzymes have gained interest for their widespread use in industries and medicine due to... more Microbial enzymes have gained interest for their widespread use in industries and medicine due to their stability, catalytic activity, and low-cost production, compared to plant and animal analogues. Microbial enzymes are capable of degrading toxic chemical compounds of industrial and domestic wastes by degradation or via conversion to nontoxic products. Enzyme technology broadly involves production, isolation, purification, and use of enzymes in various industries (e.g., food, medicine, agriculture, chemicals, pharmacology). The development of simple technologies for obtaining highly purified novel enzymes is an actual task for biotechnology and enzymology. This chapter presents a review of the main achievements in the elaboration of modern techniques for obtaining recombinant and novel enzymes. The results of a series of the authors' investigations into the development of novel enzymatic approaches, including biosensors, for determination of practically important analytes are summarized. The described methods are related to isolation of highly purified yeast oxido-reductases: alcohol oxidase, flavocytochrome b 2 , glycerol dehydrogenase, and formaldehyde dehydrogenase. The enzymes were isolated from selected or recombinant yeast cells using the simple and effective technologies developed by the authors.

Applied Sciences, 2021

Nanozymes (NZs) are nanostructured artificial enzymes that mimic catalytic properties of natural ... more Nanozymes (NZs) are nanostructured artificial enzymes that mimic catalytic properties of natural enzymes. The NZs have essential advantages over natural enzymes, namely low preparation costs, stability, high surface area, self-assembling capability, size and composition-dependent activities, broad possibility for modification, and biocompatibility. NZs have wide potential practical applications as catalysts in biosensorics, fuel-cell technology, environmental biotechnology, and medicine. Most known NZs are mimetics of oxidoreductases or hydrolases. The present work aimed to obtain effective artificial peroxidase (PO)-like NZs (nanoPOs), to characterize them, and to estimate the prospects of their analytical application. NanoPOs were synthesized using a number of nanoparticles (NPs) of transition and noble metals and were screened for their catalytic activity in solution and on electrodes. The most effective nanoPOs were chosen as NZs and characterized by their catalytic activity. Ki...

Massive use of fossil fuels has led to an increase in the CO2 concentration in the atmosphere, an... more Massive use of fossil fuels has led to an increase in the CO2 concentration in the atmosphere, and this has caused global climate changes. In contradistinction, biofuels, which are produced from plant sources, and in particular biodiesel, do not affect the greenhouse gas balance. Conventional sources of biodiesel are agricultural crops, such as corn, soybean, canola, cotton, mustard, and palm. However, use of these crops for biodiesel leads to the depletion of global food resources. The aim of the present study was to develop a scheme for rapid and efficient production of biodiesel from brown grease, i.e. cooking oil waste, which has a high free fatty acids content. Biodiesel is produced by free fatty acid esterification and triglyceride trans-esterification [1]. These processes can be performed under thermal activation and classical homogeneous catalysis; however, this scheme cannot serve for production of biodiesel in a continuous regime [2]. The present research proposes performa...

Pathogens, 2021

Conventional methods of onychomycosis treatment are ineffective in some cases because the cure of... more Conventional methods of onychomycosis treatment are ineffective in some cases because the cure of onychomycosis very often depends on the patient’s individual response to the treatment; therefore, there is a crucial need to research and develop new methods of onychomycosis therapy. One of the most innovative treatments is photodynamic therapy (PDT) using photosensitizers (PSs). However, effective treatment depends on the correct choice of photosensitizer and substances that improve the characteristics of the final formulation. The aim of our work was to find an effective formulation for the treatment of onychomycosis. To achieve this goal, we tested the effect of three types of PSs, rose Bengal (RB), malachite green oxalate (MGO), and methylene blue (MB), on Candida albicans. The most effective PS was RB, and so the study was continued with Trichophyton rubrum. Additional comparative studies were carried out on substances included in the formulation (urea and thiourea), focusing on ...

Formaldehyde (FA) is a very toxic pollutant. FA in indoor air has a negative effect on human heal... more Formaldehyde (FA) is a very toxic pollutant. FA in indoor air has a negative effect on human health and should be removed by ventilation or by conversion to non-toxic products. The formaldehyde dehydrogenase (FdDH), a NADand glutathione-dependent enzyme from recombinant methylotrophic yeast Hansenula polymorpha, was tested for its ability to oxidize airborne FA. A continuous fluidized bed bioreactor was designed to enable a bioconversion of airborne FA by FdDH or by recombinant yeast cells immobilized in calcium alginate beads. The results demonstrated that such the bioreactor with immobilized FdDH provides 97-100% elimination of airborne FA and the bioreactor with immobilized cells eliminates 94-100% of

Biosensors, 2021

Prussian blue analogs (PBAs) are well-known artificial enzymes with peroxidase (PO)-like activity... more Prussian blue analogs (PBAs) are well-known artificial enzymes with peroxidase (PO)-like activity. PBAs have a high potential for applications in scientific investigations, industry, ecology and medicine. Being stable and both catalytically and electrochemically active, PBAs are promising in the construction of biosensors and biofuel cells. The “green” synthesis of PO-like PBAs using oxido-reductase flavocytochrome b2 is described in this study. When immobilized on graphite electrodes (GEs), the obtained green-synthesized PBAs or hexacyanoferrates (gHCFs) of transition and noble metals produced amperometric signals in response to H2O2. HCFs of copper, iron, palladium and other metals were synthesized and characterized by structure, size, catalytic properties and electro-mediator activities. The gCuHCF, as the most effective PO mimetic with a flower-like micro/nano superstructure, was used as an H2O2-sensitive platform for the development of a glucose oxidase (GO)-based biosensor. Th...

Polymers, 2020

Consumption of contaminated water may lead to dangerous and even fatal water-borne diseases. Disi... more Consumption of contaminated water may lead to dangerous and even fatal water-borne diseases. Disinfection of drinking water is the most effective solution for this problem. The most common water treatment methods are based on the use of toxic disinfectants. Composites of polymers with nanosized metals and their oxides may become a good alternative to the existing methods. Expanding the scope of our previous publication, copper, cuprous, and copper oxide nanoparticles were immobilized onto linear low-density polyethylene by a simple thermal adhesion method. The antibacterial efficiency of the immobilized nanoparticles was tested against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus in batch experiments and for the first time the efficiency of these composites is reported for continuous flow regime. Immobilized copper and cuprous oxide nanoparticles demonstrated a high ability to eradicate bacteria after 30 min. These composites showed no or very limited leach...