The Effect of Green Extraction Technologies on the Chemical Composition of Medicinal Chaga Mushroom Extracts.

The mushroom industry should implement green extraction technologies; however, there is not enough information on the differences between these techniques expressed as the chemical composition of the resulting extract. In this study, selected types of green extraction techniques (GETs) were used on Chaga (Inonotus obliquus) (Fr.) Pilát from Serbia (IS) and Mongolia (IM) to examine the differences that would enable the composition-based technology choices in the mushroom supplement industry. Subcritical water extraction (SWE), microwave-assisted (MW) extraction, and ultrasonic-assisted extraction (VAE) were used to prepare the extracts. SWE was performed at two different temperatures (120 and 200 °C), while 96% ethanol, 50% ethanol, and water were used for MW and VAE. The yield, the content of total phenols, total proteins, and carbohydrates, qualitative and quantitative analysis of phenolic compounds, carbohydrates, including α- and ß- and total glucans, and fatty acids, were determined in the obtained extracts. SWE resulted in a significantly higher yield, total polysaccharide, and glucan content than any other technique. Glucose was the most dominant monosaccharide in the SWE samples, especially those extracted at 200 °C. The MW 50% EtOH extracts showed the highest yield of total phenols. Among the tested phenolic compounds, chlorogenic acid was the most dominant. SWE can be recommended as the most efficient method for extracting commercially important compounds, especially glucans and phenols.

Bioprospecting of Selected Species of Polypore Fungi from the Western Balkans.

Growing mushrooms means meeting challenges while aiming for sustainability and circularity. Wherever the producer is located, commercial strains are the same originating from several producers. Customized strains adapted to local conditions are urgently needed. Before introducing new species to the strain development pipeline, the chemical characterization and biological activity of wild ones need to be assessed. Accordingly, the mycoceutical potential of five polypore mushroom species from Serbia was evaluated including: secondary metabolite composition, oxidative damage prevention, anti-tyrosinase, and anti-angiotensin converting enzyme (ACE). The phenolic pattern was comparable in all samples, but the amounts of specific chemicals varied. Hydroxybenzoic acids were the primary components. All samples had varying quantities of ascorbic acid, carotene, and lycopene, and showed a pronounced inhibition of lipid peroxidation (LPx) and ability to scavenge HO•. Extracts were more potent tyrosinase inhibitors but unsuccessful when faced with ACE. Fomitopsis pinicola had the strongest anti-tumor efficacy while Ganoderma lucidum demonstrated strong selectivity in anti-tumor effect in comparison to normal cells. The evaluated species provided a solid foundation for commercial development while keeping local ecology in mind.

Comparative analysis of Ag NPs functionalized with olive leaf extract and oleuropein and toxicity in human trophoblast cells and peripheral blood lymphocytes.

Dry olive leaf extract (DOLE) and its active component oleuropein (OLE) were applied as reducing and stabilizing agents to prepare colloidal 20-25 nm silver nanoparticles (Ag NPs). The Ag NPs were characterized using transmission electron microscopy, X-ray diffraction analysis, and absorption spectroscopy. The cytotoxic actions of coated Ag NPs, and their inorganic and organic components, were examined against trophoblast cells and human peripheral blood lymphocytes (PBLs), Gram-positive, Gram-negative bacteria, and yeast. The genotoxic potential was evaluated in PBLs in vitro with the comet assay. Ag/DOLE and Ag/OLE induced cytotoxic effects in both types of cells after 24 h exposure when silver concentrations were 0.025-0.2 mM. However, the most pronounced cytotoxicity exhibits Ag/OLE. Both colloids also caused reduced ROS production in both cell types at 0.1 mM and 0.2 mM, while bare Ag NPs did not alter ROS levels at any of the conditions. Functionalized Ag/DOLE and Ag/OLE did not show genotoxic effects in PBLs, while bare AgNPs increased DNA damage significantly only at 0.2 mM. Regarding the antimicrobial effects, the Ag/OLE had MIC values for all evaluated microorganisms from 0.0625 to less than 0.0312 mM. Also, the antimicrobial effect of Ag/DOLE was significantly higher on Gram-negative bacteria and yeast than on Gram-positive bacteria. Obtained results indicate that Ag/OLE induced the most pronounced biological effects, beneficial for its application as an antimicrobial agent, but with potential risks from exposure to high concentrations that could induce cytotoxicity in healthy human cells.

Artificial Neural Network Prediction of Antiadhesion and Antibiofilm-Forming Effects of Antimicrobial Active Mushroom Extracts on Food-Borne Pathogens.

The problem of microbial biofilms has come to the fore alongside food, pharmaceutical, and healthcare industrialization. The development of new antibiofilm products has become urgent, but it includes bioprospecting and is time and money-consuming. Contemporary efforts are directed at the pursuit of effective compounds of natural origin, also known as "green" agents. Mushrooms appear to be a possible new source of antibiofilm compounds, as has been demonstrated recently. The existing modeling methods are directed toward predicting bacterial biofilm formation, not in the presence of antibiofilm materials. Moreover, the modeling is almost exclusively targeted at biofilms in healthcare, while modeling related to the food industry remains under-researched. The present study applied an Artificial Neural Network (ANN) model to analyze the anti-adhesion and anti-biofilm-forming effects of 40 extracts from 20 mushroom species against two very important food-borne bacterial species for food and food-related industries-Listeria monocytogenes and Salmonella enteritidis. The models developed in this study exhibited high prediction quality, as indicated by high r2 values during the training cycle. The best fit between the modeled and measured values was observed for the inhibition of adhesion. This study provides a valuable contribution to the field, supporting industrial settings during the initial stage of biofilm formation, when these communities are the most vulnerable, and promoting innovative and improved safety management.

Barium hexaferrite nanoplatelets with polyphenol coatings for versatile applications as a stable, magnetic, and antimicrobial colloid.

Colloidal stabilization of magnetic nanoparticles is one of the most important steps in the preparation of magnetic nanoparticles for potential biomedical applications. A special kind of magnetic nanoparticle are barium hexaferrite nanoplatelets (BSHF NPLs) with a hexagonal shape and a permanent magnetic moment. One strategy for the stabilization of BHF in aqueous media is to use coatings. In our research, we used an eco-friendly tannic acid, as a coating on BSHF NPLs. As-prepared BSHF NPLs coated with tannic acid were examined with transmission electron microscopy, infrared and UV-Vis spectroscopy, electro-kinetic measurements, and their room-temperature magnetic properties were measured. Stable colloids were tested in two biological complex media and antimicrobial properties of the material were examined. To enhance the antimicrobial properties of our material, we used tannic acid as a platform for the in-situ production of silver on BSHF NPLs. New hybrid material with silver also possesses magnetic properties and excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus.

Toxicity of Silver Nanoparticles Supported by Surface-Modified Zirconium Dioxide with Dihydroquercetin.

The antibacterial performance and cytotoxic examination of in situ prepared silver nanoparticles (Ag NPs), on inorganic-organic hybrid nanopowder consisting of zirconium dioxide nanoparticles (ZrO2 NPs) and dihydroquercetin (DHQ), was performed against Gram (-) bacteria Escherichia coli and Gram (+) bacteria Staphylococcus aureus, as well as against human cervical cancer cells HeLa and healthy MRC-5 human cells. The surface modification of ZrO2 NPs, synthesized by the sol-gel method, with DHQ leads to the interfacial charge transfer (ICT) complex formation indicated by the appearance of absorption in the visible spectral range. The prepared samples were thoroughly characterized (TEM, XRD, reflection spectroscopy), and, in addition, the spectroscopic observations are supported by the density functional theory (DFT) calculations using a cluster model. The concentration- and time-dependent antibacterial tests indicated a complete reduction of bacterial species, E. coli and S. aureus, for all investigated concentrations of silver (0.10, 0.25, and 0.50 mg/mL) after 24 h of contact. On the other side, the functionalized ZrO2 NPs with DHQ, before and after deposition of Ag NPs, do not display a significant decrease in the viability of HeLa MRC-5 cells in any of the used concentrations compared to the control.

Interfacial charge transfer complex formation between silver nanoparticles and aromatic amino acids.

The optical properties of surface-modified silver nanoparticles (Ag NPs) with aromatic amino acids tryptophan (Trp) and histidine (His) were examined using the cluster model for density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. Also, the redistribution of electronic charges upon chemisorption of ligand molecules onto silver's surfaces is determined. The obtained theoretical data, on one side, undoubtedly indicate the the formation of an interfacial charge transfer (ICT) complex between silver and this type of ligand, and, on the other side, partial oxidation of surface silver atoms accompanied by an increase of electron density in ligand molecules. The ICT complex formation, based on noble metal nanoparticles, has never been reported previously to the best of our knowledge. The experimental spectroscopic measurements support the theoretical data. A new absorption band in the visible spectral range appears upon surface modification of Ag NPs, and, when exposed to air, oxidation of surface-modified Ag NPs is significantly faster than the oxidation of the unmodified ones.

Exploring electroactive microenvironments in polymer-based nanocomposites to sensitize bacterial cells to low-dose embedded silver nanoparticles.

The search for alternative antimicrobial strategies capable of avoiding resistance mechanisms in bacteria are highly needed due to the alarming emergence of antimicrobial resistance. The application of physical stimuli as a mean of sensitizing bacteria for the action of antimicrobials on otherwise resistant bacteria or by allowing the action of low quantity of antimicrobials may be seen as a breakthrough for such purpose. This work proposes the development of antibacterial nanocomposites using the synergy between the electrically active microenvironments, created by a piezoelectric polymer (poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)), with green-synthesized silver nanoparticles (AgNPs). The electrical microenvironment is generated via mechanical stimulation of piezoelectric PVDF-TrFE/AgNPs films using a lab-made mechanical bioreactor. The generated material's electrical response further translates to bacterial cells, namely Escherichia coli and Staphylococcus epidermidis which in combination with AgNPs and the specific morphological features of the material induce important antibacterial and antibiofilm activity. Both porous and non-porous PVDF composites have shown antibacterial characteristics when stimulated at a mechanical frequency of 4 Hz being the effect boosted when AgNPs were incorporated in the nanocomposite, reducing in more than 80% the S. epidermidis bacterial growth in planktonic and biofilm form. The electroactive environments sensitize the bacteria allowing the action of a low dose of AgNPs (1.69% (w/w)). Importantly, the material did not compromise the viability of mammalian cells, thus being considered biocompatible. The piezoelectric stimulation of PVDF-based polymeric films may represent a breakthrough in the development of antibacterial coatings for devices used at hospital setting, taking advantage on the use of mechanical stimuli (pressure/touch) to exert antibacterial and antibiofilm activity. STATEMENT OF SIGNIFICANCE: The application of physical methods in alternative to the common chemical ones is seen as a breakthrough for avoiding the emergence of antimicrobial resistance. Antimicrobial strategies that take advantage on the capability of bacteria to sense physical stimuli such as mechanical and electrical cues are scarce. Electroactive nanocomposites comprised of poly(vinylidene fluoride-co-trifluoroethylene (PVDF-TrFE) and green-synthesized silver nanoparticles (AgNPs) were developed to obtain material able to inhibit the colonization of microorganisms. By applying a mechanical stimuli to the nanocomposite, which ultimately mimics movements such as walking or touching, an antimicrobial effect is obtained, resulting from the synergy between the electroactive microenvironments created on the surface of the material and the AgNPs. Such environments sensitize the bacteria to low doses of antimicrobials.

Influence of glucose, sucrose, and dextran coatings on the stability and toxicity of silver nanoparticles.

Aqueous colloids, consisting of 15-30 nm-sized silver nanoparticles (Ag NPs), were prepared using the reducing and stabilizing abilities of glucose, sucrose, and dextran. The long-term stability of coated Ag NPs increases from glucose over sucrose to dextran, i.e., with the increase of the molecular weight of carbohydrate molecules. The density functional theory (DFT) calculations of the partial atomic (Mulliken) charges and adsorption energies are applied to explain the enhanced stability of coated Ag NPs. All coated Ag NPs have a significantly broader concentration range of nontoxic behavior toward pre-osteoblast cells than bare Ag NPs prepared using sodium borohydride. The carbohydrate-coated Ag NPs display the same level of toxic ability against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria as bare Ag NPs. The differences in toxicity mechanism of the coated and bare Ag NPs are a consequence of the absence and presence of co-occurring Ag+ ions in examined dispersion, respectively.

Surface-modified ZrO2 nanoparticles with caffeic acid: Characterization and in vitro evaluation of biosafety for placental cells.

The toxicity of hybrid nanoparticles, consisting of non-toxic components, zirconium dioxide nanoparticles (ZrO2 NPs), and caffeic acid (CA), was examined against four different cell lines (HTR-8 SV/Neo, JEG-3, JAR, and HeLa). Stable aqueous ZrO2 sol, synthesized by forced hydrolysis, consists of 3-4 nm in size primary particles organized in 30-60 nm in size snowflake-like particles, as determined by transmission electron microscopy and direct light scattering measurements. The surface modification of ZrO2 NPs with CA leads to the formation of an interfacial charge transfer (ICT) complex followed by the appearance of absorption in the visible spectral range. The spectroscopic observations are complemented with the density functional theory calculations using a cluster model. The ZrO2 NPs and CA are non-toxic against four different cell lines in investigated concentration range. Also, ZrO2 NPs promote the proliferation of HTR-8 SV/Neo, JAR, and HeLa cells. On the other hand, hybrid ZrO2/CA NPs induced a significant reduction of the viability of the JEG-3 cells (39 %) for the high concentration of components (1.6 mM ZrO2 and 0.4 mM CA).

Tuning Properties of Cerium Dioxide Nanoparticles by Surface Modification with Catecholate-type of Ligands.

Cerium dioxide (CeO2) finds applications in areas such as corrosion protection, solar cells, or catalysis, finding increasing applications in biomedicine. This work reports on surface-modified CeO2 particles in order to tune their applicability in the biomedical field. Stable aqueous CeO2 sol, consisting of 3-4 nm in size crystallites, was synthesized using forced hydrolysis. The coordination of catecholate-type of ligands (catechol, caffeic acid, tiron, and dopamine) to the surface-Ce atoms is followed with the appearance of absorption in the visible spectral range as a consequence of interfacial charge-transfer complex formation. The spectroscopic observations are complemented with the density functional theory calculations using a cluster model. The synthesized samples were characterized by X-ray diffraction analysis, transmission electron microscopy, and nitrogen adsorption-desorption isotherms. The ζ-potential measurements indicated that the stability of CeO2 sol is preserved upon surface modification. The pristine CeO2 nanoparticles (NPs) are nontoxic against pre-osteoblast cells in the entire studied concentration range (up to 1.5 mM). Hybrid CeO2 NPs, capped with dopamine or caffeic acid, display toxic behavior for concentrations ≥0.17 and 1.5 mM, respectively. On the other hand, surface-modified CeO2 NPs with catechol and tiron promote the proliferation of pre-osteoblast cells.

Antibacterial ability of immobilized silver nanoparticles in agar-agar films co-doped with magnesium ions.

The antibacterial ability of in situ prepared nanometer-sized silver particles, immobilized in agar-agar films, was studied as a function of the concentration of co-dopant, magnesium ions. Content of inorganic components in hybrid films was determined using inductively coupled plasma optic emission spectroscopy, and found to be low (<2 wt.-%). Morphology of prepared hybrid films, studied by transmission electron microscopy, revealed the presence of non-agglomerated and randomly distributed 10-20 nm silver nanoparticles (Ag NPs) within the agar-agar matrices. Fourier-transform infrared spectroscopy indicated the distinct chemical interaction between Ag NPs and polymer chains. Thermogravimetric analysis, as well as the determination of tensile strength, Young's modulus, and elongation at break showed improvement of thermal stability and mechanical properties of agar-agar matrices upon the incorporation of Ag NPs due to high compatibility between the hydrophilic organic component and inorganic components. The complete microbial reduction of Gram-positive bacteria Staphylococcus aureuswas observed for all agar-silver films, while satisfactory results were observed for Gram-negative bacteria Pseudomonas aeruginosa (≥99.6%). The release of Ag+ ions is suppressed by the increase of the concentration of Mg2+ ions and it was found to be significantly smaller (≤0.24 ppm) than the harmful ecological level (1 ppm).

Sorption of divalent heavy metal ions onto functionalized biogenic hydroxyapatite with caffeic acid and 3,4-dihydroxybenzoic acid.

The sorption ability of biogenic hydroxyapatite (BHAP) towards heavy metal ions (Pb, Cu, Ni, Cd, and Zn) is compared with functionalized BHAP powders with caffeic acid (CA) and 3,4-dihydroxybenzoic acid (3,4-DHBA). The functionalization of the BHAP with either CA or 3,4-DHBA is indicated by the appearance of the colored powders due to the formation of the interfacial charge transfer (ICT) complexes. The detailed characterization of as-prepared and functionalized BHAP samples was performed using transmission electron microscopy, reflection spectroscopy, thermogravimetric analysis and determination of zeta potential. All three sorbents clearly displayed preferential sorption of Pb ions when the total concentration of multi-component equimolar solutions of heavy metal ions is high. It should be emphasized that the sorption capacity of functionalized BHAP with either CA or 3,4-BHAP was found to be higher, up to 60%, compared to as-prepared BHAP without the decrease of selectivity towards Pb ions.

Drug Delivery Systems for Diabetes Treatment.

BACKGROUND: Insulin is essential for the treatment of Type 1 diabetes mellitus (T1DM) and is necessary in numerous cases of Type 2 diabetes mellitus (T2DM). Prolonged administration of anti-diabetic therapy is necessary for the maintenance of the normal glucose levels and thereby preventing vascular complications. A better understanding of the disease per se and the technological progress contribute to the development of new approaches with the aim to achieve better glycemic control. OBJECTIVE: Current therapies for DM are faced with some challenges. The purpose of this review is to analyze in detail the current trends for insulin delivery systems for diabetes treatment. RESULTS: Contemporary ways have been proposed for the management of both types of diabetes by adequate application of drug via subcutaneous, buccal, oral, ocular, nasal, rectal and pulmonary ways. Development of improved oral administration of insulin is beneficial regarding mimicking physiological pathway of insulin and minimizing the discomfort of the patient. Various nanoparticle carriers for oral and other ways of insulin delivery are currently being developed. Engineered specific properties of nanoparticles (NP): controlling toxicity of NP, stability and drug release, can allow delivery of higher concentration of the drug to the desired location. CONCLUSIONS: The successful development of any drug delivery system relies on solving three important issues: toxicity of nanoparticles, stability of nanoparticles, and desired drug release rate at targeted sites. The main goals of future investigations are to improve the existing therapies by pharmacokinetic modifications, development of a fully automatized system to mimic insulin delivery by the pancreas and reduce invasiveness during admission.

Immobilization of dextransucrase on functionalized TiO2 supports.

The TiO2 based hybrid supports with different functional groups (amino, glutaraldehyde or epoxy) were prepared and their influence on immobilization of dextransucrase (DS) was studied. Novel synthetic route for surface modification of TiO2 with amino and glutaraldehyde groups was developed taking advantage of charge transfer complex (CTC) formation between surface Ti atoms and salicylate-type of ligand (5­aminosalicylic acid (5-ASA)). The proposed coordination of 5-ASA to the surface of TiO2 powder and optical properties of CTC was presented. The pristine TiO2 and amino functionalized TiO2 have higher sorption capacity for DS (12.6 and 12.0mgg-1, respectively) compared to glutaraldehyde and epoxy activated supports (9.6 and 9.8mgg-1, respectively). However, immobilized enzyme to either glutaraldehyde or epoxy functionalized TiO2 have almost two times higher expressed activities compared to pristine TiO2 support (258, 235 and 142IUg-1, respectively). Thermal stability of enzyme immobilized on glutaraldehyde and epoxy functionalized supports was studied at 40°C, as well as operational stability under long-run working conditions in repeated cycles. After five cycles, DS imobilized on glutaraldehyde activated support retained almost 70% of its initial expressed activity, while, after five cycles, performance of DS immobilized on epoxy activated support was significantly lower (15%).

Acute toxicity study in mice of orally administrated TiO2 nanoparticles functionalized with caffeic acid.

The acute toxicity of surface-modified TiO2 nanoparticles (NPs) with caffeic acid (CA) was compared with those of its separate constituents (free CA and bare TiO2 NPs) upon their oral administration in laboratory mice. Prior to in vivo experiments, the interfacial charge transfer (ICT) complex between surface Ti atoms and CA is thoroughly characterized. Composition and stability constants of ICT complex were determined using Job's method and Banesi-Hildebrand analysis, respectively. The experimental data were supported with quantum chemical calculations based on density functional theory (DFT). Acute toxicity signs, including biochemical alterations and extensive histopathological changes in the liver tissue of mice were detected 14 days after oral administration of bare TiO2 NPs. However, the clinical signs of toxicity, the fractional contribution of organs, biochemical parameters of liver and kidney function, and histopathological changes in liver upon treatment with surface-modified TiO2 NPs with CA were not observed. Also, the genotoxic potential of the ICT complex and its constituents were evaluated in leukocytes of whole blood cells in vivo by comet assay. Both, bare and surface-modified TiO2 NPs did not display DNA damaging effect in time frame of 24 h upon their oral administration in mice.

Dextran coated silver nanoparticles - Chemical sensor for selective cysteine detection.

A simple, fast and non-costly method for selective cysteine (Cys) detection, based on optical changes of silver colloids, is developed. For that purpose, stable colloids consisting of silver nanoparticles (Ag NPs) coated with polysaccharide dextran (Dex), isolated from bacterium species Leuconostoc mesenteroides T3, were prepared. The synthesized samples were thoroughly characterized including absorption and FTIR spectroscopy, as well as transmission electron microscopy and X-ray diffraction analysis. The silver colloids display high sensitivity and selectivity towards Cys detection in aqueous solutions. The Ag NPs coated with Dex provide possibility to detect Cys among a dozen amino acids and its detection limit was found to be 12.0µM. The sensing mechanism - red shift of optical absorption - is discussed in terms of the agglomeration of Ag NPs due to formation of hydrogen bonds between Cys molecules attached to different Ag NPs.

Surface-modified TiO2 nanoparticles with ascorbic acid: Antioxidant properties and efficiency against DNA damage in vitro.

The antigenotoxic and antioxidative properties of surface-modified TiO2 nanoparticles (NPs) with ascorbic acid (AA) were compared with those of constituents (free AA and bare TiO2 NPs). Colloids consisting of the TiO2 NPs with anatase crystal structure were prepared by acidic hydrolysis of TiCl4. The synthesized TiO2 NPs were characterized using transmission electron microscopy and X-ray diffraction analysis. The charge transfer (CT) complex formation between surface Ti atoms and AA is indicated by immediate appearance of red color. Composition and stability constants of CT complex were determined using Job's method and Banesi-Hildebrand analysis, respectively. The surface structure of CT complex was determined from infra-red spectra of free and bound AA to the surface Ti atoms. The experimental data were supported with quantum chemical calculations based on density functional theory (DFT). The antigenotoxic potential of CT complex was evaluated in leukocytes of whole blood cells in vitro by comet assay method. For evaluation of antioxidant properties, total antioxidant status (TAS) and total oxidant status (TOS) were determined in human serum pool in vitro. The presented results indicate that bare TiO2 NPs have more pronounced antigenotoxic effects in comparison with either surface-modified TiO2 NPs with AA or free AA. No significant differences between the antigenotoxic and antioxidative properties of free and bound AA on the TiO2 NPs were noticed in the investigated concentration range. It seems that surface-modified TiO2 NPs with AA and/or similar compounds can be used to maintain its beneficial activities.

Production of bioethanol from pre-treated cotton fabrics and waste cotton materials.

This study highlights the potential of cotton fabric as a promising feedstock for the production of bioethanol as renewable biofuel. The effect of corona pre-treatment of non-mercerized and mercerized cotton fabrics on glucose and ethanol yield is discussed. Fermentation kinetics for ethanol production and the basic process parameters were assessed and compared. Corona pre-treatment of cotton fabrics led to an increase in the glucose yield (compared to control sample) during enzymatic hydrolysis, and consequently the ethanol yield during fermentation by yeast Saccharomyces cerevisiae var. ellipsoideus. The system with mercerized cotton fabric was found to be superior obtaining an ethanol productivity of 0.900g/Lh and ethanol yield of 0.94g/g (based on glucose) after 6h of fermentation time. The similar results were obtained during processing of waste cotton materials performed under the same process conditions. The obtained results showed that cotton fabric could become an alternative feedstock for the bioethanol production. For potential industrial implementation the waste mercerized cotton scraps would be the materials of choice.

Impregnation of cotton fabric with silver nanoparticles synthesized by dextran isolated from bacterial species Leuconostoc mesenteroides T3.

This study was aimed to highlight the possibility of cotton fabric impregnation with silver nanoparticles synthesized by dextran isolated from Leuconostoc mesenteroides T3 in order to obtain antimicrobial properties. The fabrication of dextran was proved by FTIR spectroscopy. Particle sizes of synthesized dextran and silver nanoparticles were measured by dynamic light scattering method. The presence of silver nanoparticles on the surface of cotton fabric was confirmed by scanning electron microscopy, X-ray diffraction measurements and reflectance spectrophotometry. Antimicrobial activity of cotton fabric impregnated with silver nanoparticles was tested against bacteria Escherichia coli and Staphylococcus aureus, and fungus Candida albicans. The results indicated that synthesized silver nanoparticles can provide satisfactory antimicrobial activity. However, maximum reduction (99.9%) of all tested microorganisms can be obtained only when 1.0mmolL(-1) colloid consisting of silver nanoparticles is applied.