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The introduction of antimicrobial nanoparticles into nanofiber coatings is significant for enhancing microbial corrosion protection. Here, electrospun polysulfone nanofiber (PSU-Nf) and PSU-Nf functionalized with biogenic silver nanoparticles (AgNPs) coatings (PSU-Nf-AgNPs) used for Cobalt (Co) corrosion resistance in a marine environment containing Aeromonas eucrenophila (A. eucrenophila). We utilized the barrier function of the PSU-Nf and the bacterial inhibition property of the AgNPs that are synthesized using bacteria. The thickness of nanofiber coatings was 233.11 ± 33.64 µm analyzed by optical microscope and beadless morphology of nanofibers was observed using scanning electron microscope (SEM). The corrosion behavior of Co coated with PSU-Nf and PSU-Nf-AgNPs in abiotic and in the presence of the bacterium environment was investigated via polarization techniques and electrochemical impedance spectroscopy (EIS). Corrosion analysis reveals that the charge transfer resistance (Rct) increased because of the addition of the nanostructure resulting in a reduction in corrosion rate. SEM micrographs show Co surface was severely damaged by a microbial corrosive attack with severe crevices. However, the PSU-Nf and especially PSU-Nf-AgNPs coated Co surface was still covered by nanofiber coatings as the bacteria colony was not noticed. In addition, the results of the performing bacterial disk diffusion method indicated that electrospun PSU-Nf-AgNPs have good antibacterial activity against Gram-positive, Gram-negative, and model biofilm bacterium. It was found that the uncoated Co surface had severe crevices and offered poor corrosion resistance under mineral salt medium with A. eucrenophila strain. Therefore, PSU-Nf-AgNPs coated Co exhibited better corrosion resistance in mineral salt medium containing bacteria.

Bu calismada, Sphagnum palustre L. bataklik-karayosunu (SPM) metilen mavisi (MB) gideriminde tekrar kullanilabilir ve ekonomik bir biyomateryal olarak kullanilmistir. Farkli pH, sicaklik, zaman, statik / calkalama kosullari, adsorban miktari ve boya konsantrasyonunun boyar madde giderimine etkileri arastirilmistir. Bataklik-karayosunu, dusuk konsantrasyon boyar maddeyi (50 mg L −1 ) 1 saat icinde neredeyse tamamini (% 99,5) giderirken, 500 mg L -1 yuksek konsantrasyonu %85 oraninda giderdigi belirlenmistir. Adsorpsiyon izoterm verilerinin Langmuir izotermi ile uygun oldugu bulunmustur. Bu duruma ilaveten, tekrar kullanilabilirlik deneyleri S. palustre ’nin en az alti renk giderimi isleminde yuksek giderim verimi ile kullanildigini gostermistir. Altinci tekrar kullanilabilirlik testinde, metilen mavisinin renk giderim verimi % 65 ± 0.2 olarak bulunmustur. Bu sonuclar, cok yonlulugu ve yeniden kullanilabilirligi nedeniyle Sphagnum’un renk giderimi uygulamasinda kullanilabilecegini onermektedir.

Microbiologically influenced corrosion is a global problem especially materials used in marine engineering. In that respect, inhibitors are widely used to control fouling and corrosion in marine systems. Most techniques used in inhibitor production are expensive and considered hazardous to the ecosystem. Therefore, scientists are motivated to explore natsural and green products as potent corrosion inhibitors especially in nano size. In this study, antibacterial and anticorrosive properties of green silver nanoparticles (AgNPs) were studied through weight loss, electrochemical characterization, and surface analysis techniques. The corrosion of copper (Cu) in artificial seawater (ASW), Halomonas variabilis (H. variabilis) NOSK, and H. variabilis + AgNPs was monitored using electrochemical measurements like open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization curves. AgNPs showed excellent antibacterial activity against pathogenic microorganisms. Electrochemical studies demonstrate a noticeable decrease in OCP and current density in ASW containing H. variabilis + AgNPs compared to both ASW and ASW inoculated with bacterium, which confirmed the decrease of corrosion rate of copper. Furthermore, the obtained voltammograms show that the silver nanoparticles were adsorbed on the copper electrode surface from the corrosion solution. Thus, the results prove that the novel idea of green silver nanoparticles acts as an anticorrosive film in the marine environment.

Nanofibers with inorganic nanoparticles are novel hybrid nanocomposites that have great potential in various areas. In the present study, cellulose acetate nanofibers (CA-Nf) loaded with biogenic silver nanoparticles were prepared and characterized. In situ synthesis of silver nanoparticles was accomplished using a bacteria free solution as a reducing agent. Nanofibers incorporated with silver nanoparticles were fabricated using the electrospinning technique. Upright microscopy and SEM micrographs depicted that the CA-Nf coatings consist of dense and compact entangled nanofibers that completely cover the copper surface. Corrosion measurements were performed by potentiodynamic polarization measurements and electrochemical impedance spectroscopy (EIS) techniques on the bare copper and CA-Nf and CA-Nf_5% AgNp coated copper surfaces in artificial seawater (ASW) and Escherichia coli ATCC 13883 inoculated solutions. Weight loss and electrochemical corrosion test results revealed that the CA-Nf-coated copper had greater corrosion resistance than bare copper. The additional electrospun CA-Nf_5% AgNp coating also had greater antibacterial behavior toward model biofilm bacterium Pseudomonas aeruginosa than uncoated copper specimens. Therefore, this nanofiber with AgNps was demonstrated as an efficient anticorrosive material in both corrosive and biocorrosive marine solutions.

Polyvinyl alcohol (PVA) electrospun nanofibers and boric acid (BA) complexes of these nanofibers were synthesized with and without using TritonX-100(TX-100) as a water soluble surfactant (PVA, PVA/BA, PVA/TX-100, PVA/TX-100/BA). The electrospun nanofibers were characterized by SEM, FTIR and TGA. Preliminary results showed that certain amount of boric acid decreased the number of Stapylococcus aureus from 6,8x10(7)(CFU/mL) to 3x10(7)(CFU/mL). In the preparation of polymer, boric acid was used as a crosslinker and antimicrobial agent whereas TX-100 was used as surfactant. The viscosity and conductivity measurements indicated that the BA increased viscosity but decreased conductivity. In contrast, TX-100 increased conductivity without considerable effect on viscosity, which affects the production and resulting nanofiber properties such as diameter and bead formation. The antimicrobial activities of the nanofibers were assayed in vitro by Gram-negative (E. coli) and Gram-positive(S. aureus) bacteria. It was observed that PVA/TX-100/BA showed better antibacterial activity against S.aureus bacteria compared to PVA and PVA/TX-100 nanofibers.

In this study, preparation and application of novel biocomposite materials for textile dye removal which are produced by immobilization of specific bacteria onto electrospun nanofibrous webs are presented. A textile dye remediating bacterial isolate, Clavibacter michiganensis, was selected for bacterial immobilization, a commercial reactive textile dye, Setazol Blue BRF-X, was selected as the target contaminant, and electrospun polycaprolactone (PCL) and polylactic acid (PIA) nanofibrous polymeric webs were selected for bacterial integration. Bacterial adhesion onto nanofibrous webs was monitored by scanning electron microscopy (SEM) imaging and optical density (OD) measurements were performed for the detached bacteria. After achieving sufficient amounts of immobilized bacteria on electrospun nanofibrous webs, equivalent web samples were utilized for testing the dye removal capabilities. Both bacteria/PCL and bacteria/PLA webs have shown efficient remediation of Setazol Blue BRF-X dye within 48 hat each tested concentration (50, 100 and 200 mg/L), and their removal performances were very similar to the free bacteria cells. The bacteria immobilized webs were then tested for five times of reuse at an initial dye concentration of 100 mg/L, and found as potentially reusable with higher bacterial immobilization and faster dye removal capacities at the end of the test. Overall, these findings suggest that electrospun nanofibrous webs are available platforms for bacterial integration and the bacteria immobilized webs can be used as starting inocula for use in remediation of textile dyes in wastewater systems. (C) 2017 Elsevier Ltd. All rights reserved.

WOS: 000475871000007 Nanosized silver (Ag) borate particles were synthesized under facile and controlled conditions for the antibacterial ceramic applications. Obtained powder materials were characterized comprehensively for the detection of crystallinity, particle size, morphology and surface characteristics. Since obtained borate particles must be optimized by comparing their size, shape and composition, a statistical method (Taguchi Method) was used. Taguchi method allowed the control and deep insight on the variables namely temperature, reaction time, mol ratio and stirring speed. Since obtained nanoparticles can be easily modified and dispersed in ceramic matrixes, formation parameters for the best antibacterial glaze composition were defined. Structural analysis and crystallinity investigation with x-ray diffraction showed that temperature has a huge impact on the formation of nanoparticles as diffraction patterns revealed. Scanning Electron Microscopy unveiled that morphology of the nanoparticles are relatively spherical and EDX revealed that there is no other impurities. Synthesized nanoparticles were utilized for the 1 x 1 cm ceramic samples for antibacterial applications. Results showed that gram positive and gram negative bacterias are deactivated as tests revealed and reported. Manisa Celal Bayar University Coordination Unit For Scientific Research Projects (BAP) [2014-152] Support of this work by the Manisa Celal Bayar University Coordination Unit For Scientific Research Projects (BAP) (Project No: 2014-152).

Nowadays, green and efficient synthetic strategies have been gaining great interest for the synthesis of nanoparticles. In this study, the biosynthesis of silver nanoparticles and its photocatalytic activity for photodegradation of organic dye and antimicrobial property was studied. The initial syntheses of Ag nanoparticles were characterized by UV–Vis spectrophotometer and showed the surface plasmon resonance band at 430-450 nm. Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) study showed evidence that proteins are possible reducing agents. The structure of AgNPs was determined by Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). SEM and TEM studies revealed the synthesized AgNPs to be spherical. The AgNPs exhibited photocatalytic activity for photodegradation of organic dye such as Methylene Blue. Approximately 18% degradations of methylene blue within 4 h was observed with biosynthesized Ag nanoparticles in the photocatalytic degradation process.

Cyclodextrins (CD) are cyclic oligosaccharides produced from the enzymatic degradation of starch as a white powder form; on the other hand, they can be transformed into ultrathin electrospun fiber form by electrospinning technique. The electrospun cyclodextrin fibers (CD-F) can be quite attractive materials to encapsulate bacteria for bioremediation purposes. For instance, CD-F not only serve as a carrier matrix but also it serves as a feeding source for the encapsulated bacteria. In the present study, we demonstrate a facile approach by encapsulation of bacteria into CD-F matrix for wastewater treatment application. The natural and non-toxic properties of CD-F render a better bacterial viability for fibrous biocomposite. The encapsulated bacteria in CD-F exhibit cell viability for more than 7 days at 4 °C storage condition. Furthermore, we have tested the bioremediation capability of bacteria/CD-F biocomposite for the treatment of heavy metals (Nickel(II) and Chromium(VI)) and textile dye (Reactive Black 5, RB5). The bacteria/CD-F biocomposite has shown removal efficiency of Ni(II), Cr(VI) and RB5 as 70 ± 0.2%, 58 ± 1.4% and 82 ± 0.8, respectively. As anticipated, the pollutants removal capabilities of the bacteria/CD-F was higher compare to free bacteria since bacteria can use CD as an extra carbon source which promotes their growth rate. This study demonstrates that CD-F are suitable platforms for the encapsulation of bacterial cells to develop novel biocomposites that have bioremediation capabilities for wastewater treatment. The Scientific and Technological Research Council of Turkey (TUBITAK, project #114Y264) is acknowledged for funding the research. Dr. Uyar acknowledges The Turkish Academy of Sciences - Outstanding Young Scientists Award Program (TUBA-GEBIP) for partial funding of the research. A. Celebioglu acknowledges TUBITAK project #113Y348 for a postdoctoral fellowship. O.F. Sarioglu acknowledges TUBITAK BIDEB (2211-C) for National Ph.D. Scholarship. Appendix A

alpha-Tocopherol (alpha-TC) and alpha-TC/cyclodextrin (CD)-inclusion complex (IC) incorporated electrospun poly(lactic acid) (PLA) nanofibers (NF) were developed via electrospinning (PLA/alpha-TC-NF and PLA/alpha-TC/gamma-CD-IC-NF). The release of alpha-TC into 95% ethanol (fatty food simulant) was much greater from PLA/alpha-TC/gamma-CD-IC-NF than from PLA/alpha-TC-NF because of the solubility increase in alpha-TC; this was confirmed by a phase-solubility diagram. 2,2-Diphenyl-1-picrylhydrazyl radical-scavenging assay shows that PLA/alpha-TC-NF and PLA/alpha-TC/gamma-CD-IC-NF had 97% antioxidant activities; this value was expected to be high enough to inhibit lipid oxidation. PLA/alpha-TC-NF and PLA/alpha-TC/gamma-CD-IC-NF were tested directly on beef with the thiobarbituric acid reactive substance (TBARS) method, and the nanofibers displayed a lower TBARS content than the unpackaged meat sample. Thus, active packaging significantly enhanced the oxidative stability of the meat samples at 4 degrees C. In conclusion, PLA/alpha-TC/gamma-CD-IC-NF was shown to be promising as an active food-packaging material for prolonging the shelf life of foods. (C) 2017 Wiley Periodicals, Inc.

In this study, preparation and application of novel biocomposite materials that were produced by encapsulation of bacterial cells within electrospun nanofibrous webs are described. A commercial strain of Pseudomonas aeruginosa which has methylene blue (MB) dye remediation capability was selected for encapsulation, and polyvinyl alcohol (PVA) and polyethylene oxide (PEO) were selected as the polymer matrices for the electrospinning of bacteria encapsulated nanofibrous webs. Encapsulation of bacterial cells was monitored by scanning electron microscopy (SEM) and fluorescence microscopy, and the viability of encapsulated bacteria was checked by live/dead staining and viable cell counting assay. Both bacteria/PVA and bacteria/PEO webs have shown a great potential for remediation of MB, yet bacteria/PEO web has shown higher removal performances than bacteria/PVA web, which was probably due to the differences in the initial viable bacterial cells for those two samples. The bacteria encapsulated electrospun nanofibrous webs were stored at 4 degrees C for three months and they were found as potentially storable for keeping encapsulated bacterial cells alive. Overall, the results suggest that electrospun nanofibrous webs are suitable platforms for preservation of living bacterial cells and they can be used directly as a starting inoculum for bioremediation of water systems. (C) 2017 Elsevier B.V. All rights reserved.

We have proposed a new strategy for preparing free-standing nanofibrous webs from an inclusion complex (IC) of a well-known flavor/fragrance compound (limonene) with three modified cyclodextrins (HP beta CD, M beta CD, and HP gamma CD) via electrospinning (CD/limonene-IC-NFs) without using a polymeric matrix. The experimental and computational modeling studies proved that the stoichiometry of the complexes was 1:1 for CD/limonene systems. M beta CD/limonene-IC-NF released much more limonene at 37, 50, and 75 degrees C than HP beta CD/limonene-IC-NF and HP gamma CD/limonene-IC-NF because of the greater amount of preserved limonene. Moreover, M beta CD/limonene-IC-NF has released only 25% (w/w) of its limonene, whereas HP beta CD/limonene-IC-NF and HP gamma CD/limonene-IC-NF released 51 and 88% (w/w) of their limonene in 100 days, respectively. CD/limonene-IC-NFs exhibited high antibacterial activity against E. coli and S. aureus. The water solubility of limonene increased significantly and CD/limonene-IC-NFs were dissolved in water in a few seconds. In brief, CD/limonene-IC-NFs with fast dissolving character enhanced the thermal stability and prolonged the shelf life along with antibacterial properties could be quite applicable in food and oral care applications.

Free-standing nanofibrous webs of cyclodextrin/geraniol-inclusion complex (CD/geraniol-IC-NF) showing antibacterial, antioxidant activity and slow release of geraniol were developed as flavour/fragrance releasing materials via electrospinning. The electrospinning of CD/geraniol-IC-NFs with uniform and bead-free morphology was achieved without using a polymer matrix. Three types of CDs modified with hydroxypropyl and methyl groups (HP beta CD, M beta CD, and HP gamma CD) were used to obtain CD/geraniol-IC-NFs. The polymer-free CD/geraniol-IC-NFs allow us to attain much higher geraniol loading (similar to 11%, w/w) when compared to electrospun polymeric nanofibers containing CD/geraniol-IC (similar to 5%, w/w). Geraniol has a volatile nature, yet, a significant amount of geraniol (similar to 60-90%) was preserved in CD/geraniol-IC-NFs due to the complexation, whereas evaporation of geraniol was unavoidable for polymeric nanofibers incorporating geraniol without cyclodextrin. Short-term (3 h) temperature dependent release (37 degrees C, 50 degrees C, and 75 degrees C) and long-term open air (50 days, at RT) release tests revealed that M beta CD/geraniol-IC-NF released less geraniol compared to HP beta CD/geraniol-IC-NF and HP gamma CD/geraniol-IC-NF, indicating that much stronger inclusion complexation was formed between M beta CD and geraniol. The release of geraniol from CD/geraniol-IC-NFs prevented the colonization of Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria to a great extent, as observed in the antibacterial activity results. It was observed that CD/geraniol-IC-NFs had higher antioxidant activity compared to pure geraniol due to the solubility increase. In brief, the results reported here may open a new door to enhance the performance of essential oils and flavour/fragrances, to preserve volatile compounds from evaporation and to better understand the potential of CD/IC-NFs as carrier systems for guest compounds in the food, cosmetic and household cleaning industries.

Petroleum-contaminated soil was used to isolate and characterize biosurfactant producing bacteria. The strain could produce higher amount of biosurfactant in medium supplemented with motor oil as sole source of carbon and energy. A new biosurfactant producing bacterium, designated as Staphylococcus xylosus STF1 based on morphological, physiological, biochemical tests and 16S rRNA gene sequencing. The isolated bacterium was first screened for the ability to produce biosurfactant. Partial sequence of STF1 strain of 16S rDNA gene was highly similar to those of various members of the family Staphylococcaceae. Biochemical characterizations including FT-lR. Raman spectroscopy and Mass spectroscopy studies suggested the biosurfactant to be lipopeptide. Study also confirmed that the cell free supernatant exhibited high emulsifying activity against the different hydrocarbons. Moreover, the partially purified biosurfactant exhibited antimicrobial activity by inhibiting the growth of several bacterial species. The strain could be a potential candidate for the production of polypeptide biosurfactant which could be useful in a variety of biotechnological and industrial processes, particularly in the food and oil industry. (C) 2015 Elsevier By. All rights reserved

A contaminant resistant Lysinibacillus sp. NOSK was isolated from a soil sample and its Reactive Black 5 (RB5) and Cr(VI) removal efficiencies were investigated as a function of changes in the initial pH values, temperature, static/shaking conditions, reactive dye and Cr(VI) concentrations. In this study, an electrospun polysulfone nanofibrous web (PSU-NFW) was found to be effective in attachment of bacterial cells. Bacteria attached PSU-NFWs (bacteria/PSU-NFW) have shown highly efficient removal of RB5, as 99.7 +/- 0.9% and 35.8 +/- 0.4% for the pristine PSU-NFW. Moreover, the highest Cr(VI) removal efficiencies measured were 98.2 +/- 0.6% for bacteria attached PSU-NFW and 32.6 +/- 0.6% for the pristine PSU-NFW. Simultaneous removal of RB5 and Cr(VI) were also investigated. Reusability test results indicate that, bacteria/PSU-NFW can be reused for at least 7 cycles with 28.1 +/- 0.6% and 66.7 +/- 0.8% removal efficiencies for RB5 and Cr(VI), respectively.

In this study, we have developed microalgae immobilized by polysulfone nanofibrous web (microalgae/PSU-NFW) for the removal of reactive dyes (Remazol Black 5 (RB5) and Reactive Blue 221 (RB221). Here, an electrospinning technique was used to produce polysulfone nanofibrous web (PSU-NFW) as a free-standing material on which microalgae Chlamydomona reinhardtii was immobilized on PSU-NFW. The decolorization capacities of microalgae/PSU-NFW were significantly higher than that of pristine PSU-NFW. The decolorization rate for RB5 was calculated as 72.97 +/- 0.3% for microalgae/PSU-NFW, whereas it was 12.36 +/- 0.3% for the pristine PSU-NFW. In the case of RB221 solution, decolorization rates were achieved as 30.2 +/- 0.23 and 5.51 +/- 0.4% for microalgae/PSU-NFW and pristine PSU-NFW, respectively. Reusability tests revealed that microalgae/PSU-NFW can be used in at least three successive decolorization steps in which the decolorization rate of the RB5 was found to be 51 +/- 0.69% after the third reuse step. These results are promising and therefore suggest that microalgae/PSU-NFW could be applicable for the decolorization of dyes because of their versatility and reusability.