Reduction Of Ferric Ions Research Articles

Anthocyanin extract of Lannea microcarpa fruits stall oxidative rout associated with aflatoxin B1 hepatocarcinogenesis

Abstract The capability of anthocyanins extract of Lannea microcarpa fruits to scavenge reactive oxygen species and stall aflatoxin B 1 -mediated oxidative rout on cellular proteins, lipids and DNA was investigated. Reactive oxygen species (ROS) scavenging potentials of the anthocyanins extract of Lannea microcarpa fruits (0.2–1.0 mg/mL) was investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide ion, hydrogen peroxide, hydroxyl radical and ferric ion reducing system. Anthocyanins extract at 1.0 mg/mL scavenged DPPH, superoxide ion, hydrogen peroxide, and hydroxyl radical by 91%, 88%, 90% and 83%, respectively, it also reduced ferric ion significantly. The specific activities of reactive oxygen species detoxifying enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose 6-phosphate dehydrogenase) were significantly ( P Lannea microcarpa fruits anthocyanins. These inductions significantly ( P 1 -mediated decrease in reactive oxygen species detoxifying enzymes and compared favorably with Vitamin C. Aflatoxin B 1 -mediated elevation in the concentrations of conjugated dienes, lipid hydroperoxides, malondialdehyde, protein carbonyl and fragmented DNA were significantly ( P Lannea microcarpa fruits anthocyanins. Overall, the results of this study show that Lannea microcarpa fruits anthocyanins possesses antioxidant properties and halted aflatoxin B 1 -mediated oxidative rout on cellular proteins, lipids and DNA.

Evaluation of antioxidant, antibacterial and cytotoxic effects of green synthesized silver nanoparticles by Piper longum fruit

Silver nanoparticles synthesized through bio-green method has been reported to have biomedical applications to control pathogenic microbes as it is cost effective compared to commonly used physical and chemical methods. In present study, silver nanoparticles were synthesized using aqueous Piper longum fruit extract (PLFE) and confirmed by UV–visible spectroscopy. The nanoparticles were spherical in shape with an average particle size of 46nm as determined by scanning electronic microscopy (SEM) and dynamic light scattering (DLS) particle size analyzer respectively. FT-IR spectrum revealed the capping of the phytoconstituents, probably polyphenols from P. longum fruit extract and stabilizing the nanoparticles. Further the ferric ion reducing test, confirmed that the capping agents were condensed tannins. The aqueous P. longum fruit extract (PLFE) and the green synthesized silver nanoparticles (PLAgNPs) showed powerful antioxidant properties in in vitro antioxidant assays. The results from the antimicrobial assays suggested that green synthesized silver nanoparticles (PLAgNPs) were more potent against pathogenic bacteria than the P. longum fruit extract (PLFE) alone. The nanoparticles also showed potent cytotoxic effect against MCF-7 breast cancer cell lines with an IC 50 value of 67μg/ml/24h by the MTT assay. These results support the advantages of using bio-green method for synthesizing silver nanoparticles with antioxidant, antimicrobial and cytotoxic activities those are simple and cost effective as well.

Bridelia ferruginea Promotes Reactive Oxygen Species Detoxification in N-Nitrosodiethylamine-Treated Rats

ABSTRACTThis study was aimed at investigating the in vitro and in vivo reactive oxygen species (ROS) scavenging and detoxification potentials of aqueous extract of Bridelia ferruginea (B. ferruginea). Reactive oxygen species scavenging potentials of the aqueous leaf extract of B. ferruginea (0.2–1.0 mg/ml) was investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide ion, hydrogen peroxide, hydroxyl radical, and ferric ion reducing system. The detoxification of ROS was evaluated in N-nitrosodiethylamine-induced redox imbalance in the liver of rats. B. ferruginea extract at 1.0 mg/ml scavenged the DPPH, superoxide ion, hydrogen peroxide, and hydroxyl radical at 87%, 83%, 92%, and 86%, respectively, it also reduced ferric ion significantly. ROS detoxifying enzymes (superoxide dismutase (SOD), catalase, glutathione peroxidase, glutathione reductase, and glucose 6-phosphate dehydrogenase) activities were significantly (p < .05) induced by B. ferruginea. These inductions significantly ( p < .05) attenuated the N-nitrosodiethylamine-mediated decrease in ROS detoxifying enzymes and compared favorably with Vitamin C. N-nitrosodiethylamine-mediated elevation in the concentrations of malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and percentage DNA fragmentation were significantly (p < .05) lowered by B. ferruginea extract. Overall, the results of this study show that B. ferruginea leaf extract possess ROS scavenging and detoxification potentials.

Ficus carica Latex-Mediated Synthesis of Silver Nanoparticles and Its Application as a Chemophotoprotective Agent

The present work provides scientific support on the use of latex of Ficus carica to synthesize stable silver nanoparticles (AgNPs). AgNPs synthesized immediately after the addition of latex to silver nitrate solution at room temperature. Synthesized nanoparticles were of spherical shape with average size of 163.7 nm. Fourier transform infrared spectroscopy analysis revealed capping of proteins and phenolic compound on AgNPs, while X-ray diffraction analysis confirmed the fcc nature of AgNPs. Particles formed were stable for a long time (6 months). It was found that incorporation of AgNPs with 2 and 4% concentration exhibits synergistic increase in sun protection factor of commercial sunscreen and natural extracts ranging from 01 to 12,175% than control. Further characterization of latex and AgNPs revealed total phenolic content of 98.75 and 94.88 μg/ml. The ferric ion reduction potentials of latex and AgNPs were 79.69 and 18.79%. Reduction potential of ascorbic acid was synergistically increased after cumulative preparation of ascorbic acid with latex and AgNPs and found to be 106.76 and 101.50% for ascorbic acid + latex and ascorbic acid + AgNPs, respectively.

Copper recovery from tin stripping solution: Galvanostatic deposition in a batch-recycle system

Tin stripping is employed widely for the manufacture of printed circuit boards. At the end of stripping process, in general, 2–40g/l of Cu along with 150g/l SnO2 and ferric and nitrate ions remain in solution. The performance of an electrochemical batch recycle reactor for copper recovery from simulated tin stripping waste solutions was examined by galvanostatic plating. Galvanostatic control was achieved by the application of decreasing constant current steps which followed the concentration decay of metal ions in solution. The concentration decay was predicted by a model based on the batch recycle reactor operating under mass transport control. The current required to reduce the copper ions at the mass transfer limit at each time step was predicted from the model. These were matched against copper reclamation experiments from simulated tin stripping waste solutions using a single volumetric mass transfer coefficient as a fitting parameter. The prediction of the concentration decay of copper ions was in good agreement with the experimental data. It was found that the current efficiency for copper deposition was lowered by nitrates and oxygen present in the electrolyte due to their co-reduction at the cathode. Dissolved Fe3+ ions also influenced current efficiency for copper recovery due to the simultaneous reduction of ferric ions. The current efficiency was between 70% and 90% throughout the electrolytic process, which suggests that electrochemical copper reclamation may be a viable process.

Spectrophotometric Methods for the Determination of New Oral Penem (Faropenem) in Pure and in Formulations

Three simple, precise, accurate and economical spectrophotometric methods in ultraviolet and visible region were developed for the determination of faropenem in pure and formulations have been described. The method A is based on the reduction of ferric ion into ferrous ion by the mentioned drug in the presence of 1,10-phenanthroline to form a highly stable orange red colored ferrion complex measured at 510 nm. The method B is based on the oxidation of MBTH with Fe(III) followed by coupling with mentioned drug to form a highly stable violet colored chromogen measured at 610 nm. The method C is based on the reduction of Folin Ciocalteau (FC) reagent in alkaline medium by faropenem leading to the formation of intense blue colored chromogen measured at 740 nm. The results of analysis for all the three methods have been validated statistically and by recovery studies. The proposed methods were simple, sensitive and economical for the quantitative determination of faropenem and were successfully employed for the estimation in pure and in formulations.

Core–Shell Structure Dependent Reactivity of Fe@Fe2O3 Nanowires on Aerobic Degradation of 4-Chlorophenol

In this study, core-shell Fe@Fe₂O₃ nanowires with different iron oxide shell thickness were synthesized through tuning water-aging time after the reduction of ferric ions with sodium borohydride without any stirring. We found that these Fe@Fe₂O₃ nanowires exhibited interesting core-shell structure dependent reactivity on the aerobic degradation of 4-chlorophenol. Characterization results revealed that the core-shell structure dependent aerobic oxidative reactivity of Fe@Fe₂O₃ nanowires was arisen from the combined effects of incrassated iron oxide shell and more surface bound ferrous ions on amorphous iron oxide shell formed during the water-aging process. The incrassated iron oxide shell would gradually block the outward electron transfer from iron core for the subsequent two-electron molecular oxygen activation, but more surface bound ferrous ions on iron oxide shell with prolonging aging time could favor the single-electron molecular oxygen activation, which was confirmed by electron spin resonance spectroscopy with spin trap technique. The mineralization of 4-chlorophenol was monitored by total organic carbon measurement and the oxidative degradation intermediates were analyzed by gas chromatography-mass spectrometry. This study provides new physical insight on the molecular oxygen activation mechanism of nanoscale zerovalent iron and its application on aerobic pollutant removal.

Characterization of phenolics, in vitro reducing capacity and anti-glycation activity of red grape skins recovered from winemaking by-products

Red grape skins recovered from ten winemaking processes were analyzed for total phenolic content (Folin Ciocalteu assay), proanthocyanidins (n-butanol/HCl assay), individual phenolics (UPLC-DAD-MS), in vitro ferric ion reducing capacity and anti-glycation activity by bovine serum albumin/fructose and bovine serum albumin/methylglyoxal model systems. The aim was to assess if these by-products have potential as dietary anti-glycation agents, to prevent the glyco-oxidative stress associated with type-2 diabetes. Variability was observed in total phenolics (12.1-53.6g gallic acid Eq/kg), proanthocyanidins (7.2-51.1g/kg), anthocyanins (2.5-13.8 g malvidin 3-O glucoside Eq/kg), flavonols (0.3-2.6g quercetin 3-O glucoside Eq/kg) and reducing capacity (103-511 mmol Fe(II) Eq/kg). For all samples, the anti-glycation effectiveness was higher than that of commercial nutraceutical preparations. Hence, in spite of differences in cultivar, location of the vineyard and winemaking procedures, these by-products could be used as a source of cost-effective anti-glycation agent either as a food ingredient or as a nutraceutical preparation.

Functional stability of gelatin–lignosulphonate films and their feasibility to preserve sardine fillets during chilled storage in combination with high pressure treatment

Abstract The physico-chemical and functional stability of gelatin (G) and gelatin–lignosulphonate (GLS) films stored during 4 weeks at 21 °C, (i) in container or (ii) in contact with oil, was examined. Addition of lignosulphonate dramatically increased ABTS radical scavenging and ferric ion reducing capacities, which remained practically unaltered after the storage period. GLS films exhibited reduced elongation at break, irrespective of storage medium, and retained their water resistance. The feasibility of using GLS film to improve the quality of sardine fillets during chilled storage, alone or in combination with high pressure treatment (300 MPa/10 min/7 °C), was evaluated. The combined use of GLS film with high pressure reduced microbial growth, total volatile basic compounds (TVB) and thiobarbituric acid reactive substances (TBARS) during chilled storage. No noteworthy high pressure-induced colour changes were observed in the sardine muscle using this treatment alone, although an increase in yellowness due to the combined treatment was detected. Industrial Relevance Addition of lignosulphonate dramatically increased antioxidant properties (ABTS radical scavenging and ferric ion reducing) of gelatin films, which remained practically unaltered during 4 weeks of storage at room temperature. Application of those films confers stability during storage of chilled sardine, especially in combination with high pressure treatment. These novel packaging was promising for fish preservation.

Polyphenolic extract of Blighia sapida arilli prevents N-nitrosodiethylamine-mediated oxidative onslaught on microsomal protein, lipid and DNA

Abstract Polyphenolic extract of Blighia sapida arilli was evaluated for reactive oxygen species (ROS) scavenging and detoxification potentials in rat microsomes. ROS scavenging potentials of the polyphenolic extract of B. sapida (0.2–1.0 mg/mL) was investigated using DPPH radical, superoxide anion radical, hydrogen peroxide, hydroxyl radical and ferric ion reducing system. The detoxification of ROS was evaluated in N-nitrosodiethylamine-induced redox imbalance in rat microsomes. B. sapida polyphenolic extract (1.0 mg/mL) scavenged DPPH, superoxide anion radical, hydrogen peroxide, and hydroxyl radical by 60, 67, 63, and 57%, respectively, while ferric ion was significantly reduced. N-nitrosodiethylamine-mediated decrease in the activities of ROS detoxifying enzymes was significantly (P

In vitro antioxidant activity of the methanol extract of Basella alba L (Basellaceae) in rat testicular homogenate

The methanol extract of Basella alba (MEBa) has been shown to improve male fertility. In order to further understand its action mechanism, its antioxidant effect was investigated in vitro. To this respect, the extract was tested on antioxidant enzyme activities and lipid peroxidation using rat testicular homogenate. Furthermore, the effect of the MEBa on oxidation of β-carotene, reduction of ferric ions and scavenging of free radicals was investigated; in addition, phytochemical analyses were performed. The MEBa slightly reduced diphenyl-picrylhydrazyl (DPPH) radical, and inhibited lipid peroxidation and β-carotene oxidation. The MEBa also reduced ferric ions and stimulated the activities of glutathione reductase, catalase and superoxide dismutase. These findings suggest antioxidant properties of MEBa, that could be attributed to phenolic compounds revealed by phytochemical studies of the extract. The MEBa antioxidant properties may thus sustain its various biological activities, such as improvement of male reproductive function.

Antioxidant activity and polyphenol content of cherry stem (Cerasus avium L.) determined by LC–MS/MS

In this study, the antioxidant and antiradical properties of cherry stem (Cerasus avium L.) were examined. The ferric thiocyanate method, ferric ion (Fe3+) and cupric ion (Cu2+) reducing assays and ferrous ions (Fe3+) chelating assay were used in order to measure the antioxidant activity of the plant. Also, its antiradical activity was measured by 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity. Additionally, total phenolic and flavonoid contents of the plant were determined. It was indicated that, both the water extract of cherry stem (WECS) and ethanol extract of cherry stem (EECS) have both antioxidant and antiradical properties, and there is a correlation between these properties and the phenolic and flavonoid contents. Quantities of caffeic acid, ferulic acid, syringic acid, ellagic acid, quercetin, α-tocopherol, pyrogallol, p-hydroxybenzoic acid, vanillin, p-coumaric acid, gallic acid and ascorbic acid were detected by high performance liquid chromatography and tandem mass spectrometry (LC–MS/MS). This study will bring an innovation for further studies conducted on the antioxidant properties of WECS and EECS.

Diethylnitrosamine-induced redox imbalance in rat microsomes: protective role of polyphenolic-rich extract from Sorghum bicolor grains

This study investigates the protective role of polyphenolic-rich extract from Sorghum bicolor against diethylnitrosamine (DEN)-induced redox imbalance in rat microsomes. Reactive oxygen species (ROS) scavenging potentials of the polyphenolic extract from S. bicolor (0.2-1.0 mg/mL) was investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide ion, hydrogen peroxide, hydroxyl radical, and ferric ion reducing system. The detoxification of ROS was evaluated in DEN-induced redox imbalance in rat microsomes. Sorghum bicolor polyphenolic extract at 1.0 mg/mL scavenged the DPPH, superoxide ion, hydrogen peroxide, and hydroxyl radical at 75%, 76%, 79%, and 81%, respectively; it also reduced ferric ion significantly. The polyphenolic extract significantly (p<0.05) attenuated DEN-mediated decrease in the activities of ROS detoxifying enzymes (superoxide dismutase, catalase, glutathione peroxidase and reductase, and glucose-6-phosphate dehydrogenase). The concentrations of malondialdehyde, conjugated dienes, lipid hydroperoxide, protein carbonyl, and percentage DNA fragmentation in DEN-treated microsomes were significantly reduced by the polyphenolic extract. The results of the present study indicated that S. bicolor polyphenolic extract possessed in vitro antioxidant activity and protected microsomes from DEN-mediated oxidative stress by scavenging free radicals and ROS scavenger and inducer of ROS detoxifying enzymes.

Bioavailability study of a polyphenol‐enriched extract from Hibiscus sabdariffa in rats and associated antioxidant status

The aqueous extracts of Hibiscus sabdariffa have been commonly used in folk medicine. Nevertheless, the compounds or metabolites responsible for its healthy effects have not yet been identified. The major metabolites present in rat plasma after acute ingestion of a polyphenol-enriched Hibiscus sabdariffa extract were characterized and quantified in order to study their bioavailability. The antioxidant status of the plasma samples was also measured through several complementary antioxidant techniques. High-performance liquid chromatography coupled to time-of-flight mass spectrometry (HPLC-ESI-TOF-MS) was used for the bioavailability study. The antioxidant status was measured by ferric reducing ability of plasma method, thiobarbituric acid reactive substances assay, and superoxide dismutase activity assay. Seventeen polyphenols and metabolites have been detected and quantified. Eleven of these compounds were metabolites. Although phenolic acids were found in plasma without any modification in their structures, most flavonols were found as quercetin or kaempferol glucuronide conjugates. Flavonol glucuronide conjugates, which show longer half-life elimination values, are proposed to contribute to the observed lipid peroxidation inhibitory activity in the cellular membranes. By contrast, phenolic acids appear to exert their antioxidant activity through ferric ion reduction and superoxide scavenging at shorter times. We propose that flavonol-conjugated forms (quercetin and kaempferol) may be the compounds responsible for the observed antioxidant effects and contribute to the healthy effects of H. sabdariffa polyphenolic extract.

Antioxidant activity some endemic Iranian medicinal plants (Apiaceae)

Herbs and their products have been used in the food industry for their flavouring and biological activities since ancient times [1]. Oxidation, deterioration, and microbial reactions occurring in food products may cause economic loss [2]. In this study, seven plants were collected from their natural location in Chaharmahal va Bakhtiari and determined. By maceration method with methanol solvent, extracts were obtained. Antioxidant activity of methanolic extracts was evaluated by three assays: DPPH, FRAP & TEAC. Among the plant extracts were evaluated in FRAP assay, Echiophora platyloba DC showed relatively strong ferric ion reducing activity with 3.38mg/ml. In TEAC assay, IC50 value of E. platyloba was determine to be 1.70mg/ml. In comparing different extracts, E. platyloba was found to be better antioxidants than the other plants, correlating with its high total phenolics and flavonoids content.

Antioxidant properties and essential oil composition of Calamintha grandiflora L.

Essential oil was isolated from the leaves of Calamintha grandiflora L. by hydrodistillation and analysed by gas chromatography–mass spectrometry (GC–MS). The most abundant compounds in C. grandiflora essential oil were isomenthone, neo-isomenthol, pulegone and isomenthol, constituting 34.07%, 7.65%, 19.83% and 19.54%, respectively. The residues obtained after hydrodistillation were separated into the solid and liquid fractions, the former one was extracted with acetone, methanol and ethanol, while the latter one was sprayed or freeze dried. Antioxidant potential of extracts was evaluated by DPPH (batch and HPLC-on-line) and ABTS+ radical scavenging, ferric ion reduction (FRAP) assays and by the effect on oil peroxidation in Oxipres apparatus. The content of total phenolic compounds, flavonoids and flavonols was determined spectrophotometrically. Rosmarinic and salvianolic C acids were identified as the main antioxidants in C. grandiflora.

Experimental study of iron-control agents selection for high temperature sour gas and oil wells acidizing process

In acidizing process, the pH of acid increases gradually. When PH is higher than about 2.2, Fe3+ forms a black sticky precipitant that decreases well permeability. Therefore, using Ferric ion reducing agent as an additive is a proper way to prevent of precipitant formation. In this study, some materials are introduced as reducing agents and compared with each other. Then the effect of adding catalyst to these materials was investigated and the best mixtures were chosen and compared with commercial ferrotrol 200 from BJ service. These two mixtures include thioglycolic acid as ferric ion reducing agent and potassium iodide as a catalyst, and phosphinic acid salt as ferric ion reducing agent and potassium iodide as a catalyst. The results showed that the proposed additives have better performance at high temperature in contrast to ferrotrol 200. Then these two mixtures and ferrotrol 200 were compared with each other in the presence of H2S and calcium carbonate (representative of reservoir rock). The result showed that the two chosen mixtures mentioned above have better performances in contrast to ferrotrol 200 owing to better reduction of ferric ion and performing faster than H2S, also, prevent of FeS and S precipitants formation. After that, a comparison between these two mixtures and ferrotrol 200 has been performed in the presence of crude oil that proved these studied additives do successfully; however, additive including thioglycolic acid is more proper in acidizing process of oil wells.

Influence of oxalic acid formed on the degradation of phenol by Fenton reagent

The objective of this work is to examine the influence of oxalic acid formed on the degradation of phenol by Fenton reagent. Oxalic acid formed at initial stage within 30min significantly suppresses the reduction of ferric ion, thus terminating degradation reaction. The yield of oxalic acid is dependent on the amount of ferrous ion dosed since the minimal amount of oxalic acid is formed after the degradation reaction terminates. Mineralization of phenol by Fenton reagent stagnates after 120min under the conditions used in this study. The reason why the mineralization stagnated can be assumed to be following two mechanisms other than the depletion of H2O2. In the case where a small amount of ferrous ions is dosed, the reduction of ferric ions is minimal by oxalic acid formed. In the case where a large amount of ferrous ions is dosed, the amount of degradable organic compounds is insufficient owing to preferential conversion to oxalic acid. The mineralization can be enhanced by the intermittent dosing of ferrous ions, which facilitates the suppression of oxalic acid formation during the degradation by Fenton reagent.

Degradation of Acid Orange 7 in aqueous solution by a novel electro/Fe2+/peroxydisulfate process

A novel process in which electrochemistry (EC) was coupled with ferrous ion activation of peroxydisulfate (Fe2+/S2O82−) was proposed for the decolorization of Acid Orange 7. In this process, the reaction between peroxydisulfate and externally added ferrous ion results in the production of sulfate free radical as well as ferric ion, and at the same time ferrous ion could be electro-regenerated at the cathode by the reduction of ferric ion. Color removal by the Fe2+/S2O82− process was significantly enhanced in the presence of applied current. The effects of some important reaction parameters such as initial pH, current density, S2O82− concentration and Fe2+ concentration on the decolorization of Acid Orange 7 by EC/Fe2+/S2O82− process were investigated. The results showed that the decolorization efficiency was not significantly affected by the initial pH value, and the decolorization efficiency increased with the increase of S2O82− concentration and Fe2+ concentration. The current densities had little effect on the decolorization of Acid Orange 7 at the beginning of the reaction, while it improved the decolorization efficiency after 60min reaction. The GC–MS analysis was employed to identify the intermediate products and a plausible degradation pathway is proposed. The chemical oxygen demand (COD) removal efficiency was 57.6% after 60min reaction and it reached 90.2% when the reaction time was extended to 600min. Toxicity test with Daphnia magna showed that the acute toxicity of the solution increased during the first stage of the reaction, and then gradually decreased with the progress of the oxidation.

High‐throughput screening for cellobiose dehydrogenases by Prussian Blue in situ formation

Extracellular fungal flavocytochrome cellobiose dehydrogenase (CDH) is a promising enzyme for both bioelectronics and lignocellulose bioconversion. A selective high-throughput screening assay for CDH in the presence of various fungal oxidoreductases was developed. It is based on Prussian Blue (PB) in situ formation in the presence of cellobiose (<0.25 mM), ferric acetate, and ferricyanide. CDH induces PB formation via both reduction of ferricyanide to ferrocyanide reacting with an excess of Fe³⁺ (pathway 1) and reduction of ferric ions to Fe²⁺ reacting with the excess of ferricyanide (pathway 2). Basidiomycetous and ascomycetous CDH formed PB optimally at pH 3.5 and 4.5, respectively. In contrast to the holoenzyme CDH, its FAD-containing dehydrogenase domain lacking the cytochrome domain formed PB only via pathway 1 and was less active than the parent enzyme. The assay can be applied on active growing cultures on agar plates or on fungal culture supernatants in 96-well plates under aerobic conditions. Neither other carbohydrate oxidoreductases (pyranose dehydrogenase, FAD-dependent glucose dehydrogenase, glucose oxidase) nor laccase interfered with CDH activity in this assay. Applicability of the developed assay for the selection of new ascomycetous CDH producers as well as possibility of the controlled synthesis of new PB nanocomposites by CDH are discussed.