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(a) Viable bacterial number of E. coli and (b) viable bacterial number of S. aureus on PU and hybrid mats; (c) growth inhibition of E. coli and (d) growth inhibition of S. aureus on PU and hybrid mats.
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A hybrid nanofibrous mat consisting of polyurethane, dextran, and 10 wt % of biopigment (i.e., pyocyanin) was facilely fabricated using a direct-conventional electrospinning method. The field emission scanning electron microscopy showed the bead-free fibers with a twisted morphology for the pyocyanin-loaded mat. The addition of pyocyanin enables th...
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Context 1
... Stability. Mechanical strength of the electrospun mats was investigated by DMA, and the results are presented in Figure S4. Figure S4a shows the modulus curves of electrospun mats. ...
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... strength of the electrospun mats was investigated by DMA, and the results are presented in Figure S4. Figure S4a shows the modulus curves of electrospun mats. The maximum storage modulus of the bare PU membrane was 549 MPa, whereas the PUD and PUDP hybrid electrospun mats exhibited the maximum storage moduli of 558 and 221 MPa, respectively. ...
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... antibacterial activity was examined by immersing the PU, PUD, and PUDP membrane into the S. aureus or E. coli suspension. The count of viable cells was measured as a function of time via observation, and Figure 4a,b shows the corresponding results. It can be seen that there is no significant loss in the number of viable bacterial cells with pristine PU and PUD samples, whereas a significant decrease in the number of viable cells can be found with the PUDP sample, representing the antibacterial activity of pyocyanin. ...
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... can be seen that there is no significant loss in the number of viable bacterial cells with pristine PU and PUD samples, whereas a significant decrease in the number of viable cells can be found with the PUDP sample, representing the antibacterial activity of pyocyanin. Further, the antibacterial activity of pristine PU, PUD, and PUDP samples was further assessed by calculating the percentage of bacterial inhibition after 12 h of time and represented in Figure 4c,d. The % of bacterial inhibition for the PUDP sample was found to be 98.54 and 90.2% for E. coli and S. aureus, respectively. ...
Citations
... Dextran is water soluble, biocompatible, and biodegradable and has been applied in the field of food engineering. For example, electrospun fiber films based on dextran are used for antioxidant activity packaging 41 , edible antibacterial food packaging 42,43 and functional food 44,45 . ...
The nanofibers formed by electrospinning technology have the advantages of orderly release mechanism and controllable dissolution rate. However, the use of toxic and harmful organic solvents is widespread in the field of electrospinning, which not only poses a potential hazard to human health and the natural environment, but also increases the manufacturing cost and difficulty of electrospinning. Therefore, the purpose of this paper is to introduce the application of green electrospinning technology in food engineering. Water solvent electrospinning is mainly introduced, and some water-soluble biopolymer and synthetic polymers are reviewed. Their latest applications and development limitations in the field of food engineering are introduced and discussed. The water solvent electrospinning introduced here transforms a process that has adverse effects on the environment and health into a scalable and ecologically conscious “green” electrospinning, which is both important and timely and will bring exemplary changes to the field of food engineering.
... Fabrics treated with the microbial dye can be analysed for antimicrobial protection against the most prevalent human pathogens like Escherichia coli and Staphylococcus aureus. Materials like wool show the highest degree of antimicrobial protection towards Escherichia coli whereas silk has the same against Staphylococcus aureus (Mishra and Jahan 2018;Sheet et al. 2018). ...
Artificial colours are extensively used in various industries like food, textiles, cosmetics and pharmaceuticals. Synthetic pigments pose toxicity threats and this has provoked an interest in the field of microbial colours and dyes. Pigment producing microorganisms exhibit a promising potential in overcoming current challenges. These pigments are biodegradable and eco-friendly. At present, natural pigments, especially microbial pigments hold great significance within the market. Numerous microorganisms produce colored pigments. This review focuses on the antimicrobial and antifungal activity of pyocyanin, pigment from Pseudomonas aeruginosa. It may find application in preparation of sheets and gown for medical and hospital use. Various fermentation techniques are discussed in view of their production by some important microorganisms. Further, it also sheds light on the possibility of using this pigment as textile colourant or dye which can be used to colour cotton, wool and silk fabrics.
... Although there is considerable technological interest in creating redox-active materials for energy (Pankratov et al., 2016) and antimicrobial (Liu et al., 2018;Sheet et al., 2018) applications, our focus is redox-active hydrogels for communication (Kim et al., 2014;Li et al., 2021;Liu et al., 2017). We specifically demonstrate redox-based communication between two abiotic materials, and this expands on recent efforts toward the development of interactive materials capable of signaling with biology through its native redox modality . ...
Recent observations that abiotic materials can engage in redox-based interactive communication motivates the search for new redox-active materials. Here we fabricated a hydrogel from a four-armed thiolated polyethylene glycol (PEG-SH) and the bacterial metabolite, pyocyanin (PYO). We show that: (i) the PYO-PEG hydrogel is reversibly redox-active; (ii) the molecular-switching and directed electron flow within this PYO-PEG hydrogel requires both a thermodynamic driving force (i.e., potential difference) and diffusible electron carriers that serve as nodes in a redox network; (iii) this redox-switching and electron flow is controlled by the redox network’s topology; and (iv) the ability of the PYO-PEG hydrogel to “transmit” electrons to a second insoluble redox-active material (i.e., a catechol-PEG hydrogel) is context-dependent (i.e., dependent on thermodynamic driving forces and appropriate redox shuttles). These studies provide an experimental demonstration of important features of redox-communication, and also suggest technological opportunities for the fabrication of interactive materials.
... The microbial barrier is an essential component that influences drug absorption and metabolism. 39 Phenazines were reported to promote bacterial respiration under anoxic conditions by transferring electrons, 40 to kill bacteria by facilitating ROS accumulation, 41 and to induce oxidative stress and inflammatory response. 29 These were consistent with the accumulation of ROS and the increased inflammatory cytokines in the duodenum in our work ( Figure S9B,E). ...
... In this case, also, a greater sensitivity of Gram-negative bacteria to these newly obtained materials was observed. In addition, the percentage of the bacterial inhibition of XG/PVA-based composite films containing hydro-alcoholic extract from Feteasca Neagra and Merlot grape pomace achieved onto Escherichia coli and Listeria monocytogenes (Table 3) was superior to those already reported for other polysaccharide-based films incorporating quercetin or tannic acid [36] and were comparable only with those embedding pyocyanin [37]. Moreover, as far as we know, this is the first study which reports XG/PVA/Merlot pomace-based cryogels with an antimicrobial activity of 99% against Salmonella typhymurium. ...
Nowadays, there is a growing interest in developing functional packaging materials from renewable resources containing bioactive compounds (such as polyphenols) in order to reduce the use of petroleum-based plastics and their impact on the environment. In this regard, the effect of a variety and concentration of grape pomace extracts (Feteasca Neagra or Merlot) incorporated within ice-templated 3D xanthan-based composites was evaluated by considering their water content, surface and texture properties, radical scavenging and microbiological activities. The embedding of Feteasca Neagra or Merlot grape pomace extracts was studied by static water swelling and contact angle measurements, and SEM, EDX, and TGA analyses. The water contact angle results showed an increase in the surface hydrophobicity of the extract-loaded cryogels with an increase in extract content from 10 to 40 v/v%. SEM micrographs indicated that the entrapment of grape pomace extracts affected the morphology of the pore walls and reduced the pore sizes. The antioxidant activity of grape pomace extract-loaded composite cryogels was closely related to the total phenolic content of grape variety and to their concentration into matrices. The highly hydrophobic character of composite cryogels containing Merlot grape pomace extract and their remarkable antimicrobial activity indicates a great potential of these materials for food packaging applications.
... The film-forming ability of several polysaccharides has been studied, including chitosan, alginate, xanthan, dextran, starch, pectin, curdlan, and pullulan (Table 1; Cazon et al. 2017;Dutta et al. 2009;Espitia et al. 2014;Shankar et al. 2017). In most of the cases, the addition of plasticizers, nanofillers, and other natural or synthetic polymers, is required to obtain polysaccharides-based films with improved/enhanced water vapor permeability, the polymer chain flexibility as well as the resistance to fracture (Raschip et al. 2020a;Muscat et al. 2012;Cazon et al. 2017;Dutta et al. 2009;Cazon et al. 2018;Shankar et al. 2017;Zemljic et al. 2013;Narasagoudr et al. 2020;Han et al 2018;Ho et al. 2020;Namratha et al. 2020;Surendhiran et al. 2019;Zhou et al. 2019;Sheet et al. 2018;Shao et al. 2018). ...
... Hybrid nanofibrous mats consisting of polyurethane (PU), DEX, and pyocyanin were fabricated using electrospinning method and their properties were compared with those of pristine materials (Sheet et al. 2018). The SEM micrographs showed flat ribbon-like structure, ellipse shape structure, and round fibers with a twisted and wrinkled bend morphology for PU nanofibers ( Figure 5C), PU/DEX nanofibers ( Figure 5D) and pyocyanin-loaded mats (Figure 5E), respectively. ...
... Coverage significantly altered hardness, gumminess, chewiness and cohesiveness over time, while elasticity was not affected. Polyurethane/DEX Membranes(Sheet et al. 2018) PyocyaninThe bacterial inhibition test revealed that the antibacterial activity of electrospun mat containing pyocyanin was 98.54 and 90.2% toward E. coli and S. aureus, respectively. PL films(Esposito et al. 2020) ...
Nowadays, the movement of goods without packaging is almost unthinkable; therefore, the implementation and development of new packaging products and processes are highly required. In designing two-component product-package systems, both the impact of the raw materials and their elimination or reuse after exceeding their lifetime must be taken into account. Consequently, abundant, nontoxic, renewable, biocompatible, and eco-friendly polymers like polysaccharides (chitosan, alginate, xanthan gum, dextran, salecan, pullulan, and curdlan) are good alternatives and key factors to reduce the quantity of plastics, which are practically nonbiodegradable. In addition, the antioxidant-loaded polysaccharide films or coatings have been shown to exhibit an important function in safeguarding of foods against bacterial spoilage organisms by their remarkable antioxidant activity. Anyway, the bio-based packaging materials cannot take fully the place of the synthetic-based plastics, but they can lower the total cost of packaging and the amount of the plastics exploited. Main factors which control the synthesis of polysaccharide-based packaging materials and their morphological, mechanical, thermal, and water sorption features are discussed in this chapter based on the recently published articles and our own results.
... Interestingly, the release% of NOR was estimated to be 15% within 24 h. The same results was reported for nanofibrous hybrid mat consisting of polyurethane, dextran, and 10 wt % of pyocyanin [47] and for PU-dextran nanofibrous mats loaded with ciprofloxacin HCl [48]. Bacterial cell death by SPIO NPs was attributed to the generation of reactive oxygen species or toxic hydroxyl free radicals through Fenton reaction that interfere with the electron transport process leading to damage of lipids, proteins and DNA [49][50][51][52]. ...
To achieve efficient therapeutic effect and limit side effects, an in vitro thermo-triggered drug release was designed. Superparamagnetic iron oxide nanoparticles (SPIO NPs) was synthesized, loaded by Norfloxacin (NOR) as a model drug and coated with polyurethane urea (PUU). PUU was prepared using isophorondiisocyanate, polyethylene glycol with different molecular weights and water as a chain extender. A hierarchical morphology and thermal behavior of the resulting nanocomposites ([email protected]) were examined by XRD, SEM, TEM, TGA and zeta potential analyzer. The effects of different amounts of SPIO NPs and concentration of drug on loading capacity were investigated. The release behavior of the drug is influenced by the composition of the carriers, loading capacity of the drug, pH, ionic strength and temperature. At 25 °C, none of drug is released from [email protected](3)-PUU(400) while at slightly elevated temperature 37 °C, a controlled release of the drug was observed however, at 45 °C a burst release was detected. The mechanism of drug release, antimicrobial efficacy and cytotoxic effect of nanocomposite loaded drug were investigated. The release of the drug from [email protected](3)-PUU(400) at 37 °C follows Fickian diffusion mechanism however, at 45 °C follows first order mechanism. The nanocomposite loaded drug ([email protected](3)-PUU(400)) demonstrated 2- fold increase in antibacterial efficacy against E-Coli, compared with free drug. A significant cytotoxicity of [email protected](3)-PUU(400) against MCF-7 cell lines cell lines was noticed with moderate effect on Human lung fibroblast cell line (WI38).
... During quantification of ROS generation in cells, DCFH-DA oxidized into highly fluorescent 2',7'-dichlorodihydrofluorescein (DCF) by the action of ROS. [35] When S. aureus was treated with 5 b, 5 j, or 5 q, the fluorescent DCF dye was changed to DCF + and showed good fluorescence intensity due to the compound-induced intracellular ROS formation ( Figure 3). A population of DCF + cells showed higher fluorescence intensity for molecules 5 b and 5 j than 5 q. ...
... The obtained data were extracted using FlowJo 10.0.7 software (Treestar Inc, Ashland, OR, US). [35] ...
1,4‐Naphthoquinones are an important class of compounds present in a number of natural products. In this study, a new series of 1,4‐naphthoquinone derivatives were synthesized. All the synthesized compounds were tested for in vitro antimicrobial activity. In this present investigation, two Gram‐positive and five Gram‐negative bacterial strains and one pathogenic yeast strain were used to determine the antibacterial activity. Naphthoquinones tested for its antibacterial potencies, among seven of them displayed better antimicrobial activity against Staphylococcus aureus (S. aureus; 30–70 μg/mL). Some of the tested compounds showed moderate to low antimicrobial activity against Pseudomonas aeruginosa (P. aeruginosa) and Salmonella bongori (S. bongori; 70–150 μg/mL). In addition, most active compounds against S. aureus were evaluated for toxicity to human blood cells using a hemolysis assay. For better understanding, reactive oxygen species (ROS) generation, time‐kill kinetic study, and apoptosis, necrosis responses were investigated for three representative compounds.
... Finally, the stained cells were counted using a BD FACSCalibur flow cytometer (San Jose, California, USA). The acquired data were isolated using FlowJo 10.0.7 software (Treestar Inc, Ashland, OR, US) [28]. ...
1,4-Naphthoquinones have antibacterial activity and are a promising new class of compound that can be used to treat bacterial infections. The goal was to improve effective antibacterial agents; therefore, we synthesized a new class of naphthoquinone hybrids, which contain phenylamino-phenylthio moieties as significant counterparts. Compound 4 was modified as a substituted aryl amide moiety, which enhanced the antibacterial activity of earlier compounds 3 and 4. In this study, five bacterial strains Staphylococcus aureus (S. aureus), Listeria monocytogenes (L. monocytogenes), Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Klebsiella pneumoniae (K. pneumoniae) were used to evaluate the antibacterial potency of synthesized naphthoquinones using the minimal inhibitory concentration (MIC) method. Most of the studied naphthoquinones demonstrated major antibacterial activity with a MIC of 15.6 µg/mL–500 µg/mL. Selected compounds (5a, 5f and 5x) were studied for the mode of action, using intracellular ROS generation, determination of apoptosis by the Annexin V-FITC/PI assay, a bactericidal kinetic study and in silico molecular modelling. Additionally, the redox potentials of the specified compounds were confirmed by cyclic voltammetry (CV).
... Finally, the stained cells were counted using a BD FACSCalibur flow cytometer (San Jose, California, USA). The acquired data were isolated using FlowJo 10.0.7 software (Treestar Inc, Ashland, OR, US) [28]. ...
1,4-Naphthoquinones have antibacterial activity and are a promising new class of compound
that can be used to treat bacterial infections. The goal was to improve effective antibacterial agents;
therefore, we synthesized a new class of naphthoquinone hybrids, which contain phenylamino-phenylthio
moieties as significant counterparts. Compound 4 was modified as a substituted aryl amide moiety,
which enhanced the antibacterial activity of earlier compounds 3 and 4. In this study, five bacterial
strains Staphylococcus aureus (S. aureus), Listeria monocytogenes (L. monocytogenes), Escherichia coli (E. coli),
Pseudomonas aeruginosa (P. aeruginosa) and Klebsiella pneumoniae (K. pneumoniae) were used to evaluate
the antibacterial potency of synthesized naphthoquinones using the minimal inhibitory concentration
(MIC) method. Most of the studied naphthoquinones demonstrated major antibacterial activity with
a MIC of 15.6 µg/mL–500 µg/mL. Selected compounds (5a, 5f and 5x) were studied for the mode of
action, using intracellular ROS generation, determination of apoptosis by the Annexin V-FITC/PI assay,
a bactericidal kinetic study and in silico molecular modelling. Additionally, the redox potentials of the
specified compounds were confirmed by cyclic voltammetry (CV).
