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EN
In this study, optimal conditions to form cellulose-MgO nanocomposite with antibacterial properties were evaluated. Applying the Taguchi method, 9 experiments were designed and the effects of different concentrations of biopolymers cellulose (0.5, 1 and 2 mg/ml), MgO nanoparticles (2, 4 and 8 mg/ml) and stirring times (30, 60 and 90 min) on antibacterial activity of synthesized nanocomposites were assessed. The characterizations of products were investigated by dynamic light scattering (DLS), raman spectroscopy, scanning electron microscope (SEM), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The results showed that the nano-composite produced in the conditions of experiment 9 (MgO 8 mg/ml, cellulose 2 mg/ml and stirring time of 60 min) has the strongest antibacterial activity. The outcomes of both methods of colony forming units (CFU) and disc diffusion indicated that the antibacterial activity of cellulose-MgO nanocomposite was significantly higher than its components (P <0.05). Thermal analysis indicated improvement in the thermal stability of the cellulose biopolymer after the formation of the nanocomposite. Due to the improvement of the antibacterial properties of cellulose-MgO nanocomposite compared to its components, we can use it as a new antibacterial agent in the fields of pharmaceutical, medicine and dentistry.
EN
The field of nanotechnology is the most dynamic region of research in material sciences and the synthesis of nanoparticles is picking up significantly throughout the world. This trend is related to the possibilities of using them in many disciplines, including microbiology, biotechnology and laboratory diagnostics. Due to the high interest in nanoparticles synthesis, the methods of formation and stabilization of nanometric particles have become the subject of many studies in recent years. Medicinally active plants have proven to be the best reservoirs of diverse phytochemicals for the synthesis of biogenic silver nanoparticles. The resulting structures are characterized by optimal properties, and the method used is more ecological than chemical reduction. Accordingly, this review presents different methods of preparation silver nanoparticles and application of these nanoparticles in different fields.
PL
Nanotechnologia jest jedną z najbardziej dynamicznych dyscyplin badań w dziedzinie inżynierii materiałowej, a liczba syntez nanocząstek metali znacząco rośnie na całym świecie. Ten trend związany jest z możliwościami wykorzystania ich w wielu dyscyplinach nauki, m.in. mikrobiologii, biotechnologii i diagnostyce laboratoryjnej. Ze względu na duże zainteresowanie nanocząstkami metody tworzenia i stabilizacji nanometrycznych cząstek stały się w ostatnich latach przedmiotem wielu badań. Udowodniono, że ekstrakty roślinne, zawierające zespół związków fitochemicznych, mogą być wykorzystywane do syntezy biogennych nanocząstek srebra. Powstałe struktury charakteryzują się stosownymi właściwościami, a metoda „zielonej” syntezy jest bardziej ekologiczna od innych technik. W związku z tym w artykule przedstawiono różne metody biosyntezy nanocząstek srebra oraz ich interdyscyplinarne zastosowania.
EN
Supercritical carbon dioxide dyeing, a new type of anhydrous dyeing method, has a lot of advantages, mainly conservation of energy, prevention of pollution, reusability of dye, and many more. This study presents a viable method for the dyeing of an ultra-high-molecular-weight polyethylene (UHMWPE) fabric by using supercritical carbon dioxide (scCO2) as a medium. Five hydrozono propanenitrile dyes that are functional colorants having antibacterial activity were applied for the dyeing of the UHMWPE fabric in scCO2 at a pressure of 20 MPa and at temperature of 120°C. The dyeability of UHMWPE fabric under scCO2 was evaluated by color measurement, whereby the color strength K/S was calculated. As the treating time and concentration of dye increased, the dyeability of the UHMWPE fabric displayed the tendency to continually improve. As decaline was added into scCO2 as the cosolvent, we obtained higher K/S. Furthermore, color fastness to rubbing and sublimation of the dyed UHMWPE fabric were determined according to Japanese Industrial Standards (JIS) L 0849 2 and JIS L 0854, and the trend showed that the increase in fastness corresponded to the increase in duration of the treatment. The influence of scCO2 dyeing on the mechanical properties of UHMWPE was also examined. Consequently, it was found that dyeing in scCO2 containing decaline reduced the crystallinity of the UHMWPE fabric and the breaking strength decreased. The antimicrobial property of UHMWPE dyed with N′-(2-chloro-4-methylphenyl)-2-oxo-2-(p-tolyl)acetohydrazonoyl cyanide was tested against three different microorganisms, and the results have been reported.
EN
In this study, it was aimed to synthesize hydrogel based antibacterial, biocompatible and non-toxic wound dressing materials by solvent removal method usingpoly(vinylalcohol) (PVA), poly(vinylpyrolidone) (PVP) and nano pomegranate seed (PN).The morphology, swelling capacity, contact angle, antibacterial activity, biocompatibility and cytotoxicity of the synthesized films were determined. From the experimental findings, it was found that the PN particles were nano-sized, showed homogeneous and spherical distribution and improved the hydrophobic properties of the materials obtained by the addition of PN. And also, their swelling capacities were decreased with increased PN amount and all of the materials showed similar antibacterial activity, hemocompatibility and cytotoxicity.
EN
This chapter reviews the research on antibacterial functionalization of textiles with inorganic nanoparticles (Ag, MgO, Al2O3) by the sonochemical method. Sonochemistry is one of the most efficient techniques for the synthesis of nanosized materials, wherein ultrasonic waves in the frequency range of 20 kHz to 1 MHz serve as a driving force for chemical reactions. Sonochemical reactions are dependent on acoustic cavitation: the formation, growth, and explosive collapse of bubbles in irradiated liquids. Extreme conditions are developed when the bubbles collapse (temperature >5000 K, pressure >1000 atm, and cooling rates >109 K/sec), resulting in the breaking and forming of chemical bonds. The deposition of nanoparticles on the surface of natural and synthetic yarns and fabrics (wool, cotton, nylon, polyester) may be achieved using ultrasound irradiation. This process produces a uniform coating of nanoparticles on the textile surface with different functional groups. The coating can be performed by an in situ process, where the nanoparticles are formed and immediately propelled to the surface of the fabric. This approach was demonstrated with nanosilver. Alternatively, the sonochemical process can be used as a "throwing stone" technique, where previously synthesized nanoparticles are sonicated in the presence of the fabric. This process was shown with MgO and Al2O3 nanoparticles, which were propelled to the surface by microjets and adhered strongly to the textile without any additional binder. This phenomenon was explained because of the local melting of the substrate due to the high rate and temperature of nanoparticles propelled at the solid surface by sonochemical microjets. The activity of the fabric finishing with antibacterial nanoparticles was tested against Gram-negative and Gram-positive bacteria cultures. A significant bactericidal effect was demonstrated in both cases, even at a low concentration, below 1 wt.% of nanoparticles in the fabric.
PL
Dokonano przeglądu badań nad funkcjonalizacją antybakteryjną wyrobów włókienniczych nanocząsteczkami nieorganicznymi (Ag, MgO, Al2O3 ) metodą sonochemiczną. Sonochemia jest jedną z najskuteczniejszych technik syntezy nanomateriałów, w której fale ultradźwiękowe w zakresie częstotliwości od 20 kHz do 1 MHz służą jako siła napędowa dla reakcji chemicznych. Reakcje sonochemiczne są zależne od kawitacji akustycznej: powstawania, wzrostu i wybuchowego rozpadu pęcherzyków w napromieniowanych cieczach. Ekstremalne warunki powstają, gdy pęcherzyki zapadają się (temperatura > 5000 K, ciśnienie > 1000 atm, szybkość chłodzenia > 109 K/s), powodując pękanie i tworzenie wiązań chemicznych. Osadzanie nanocząsteczek na powierzchni przędz i tkanin naturalnych i syntetycznych (wełna, bawełna, nylon, poliester) można uzyskać za pomocą napromieniowania ultradźwiękowego. W tym procesie uzyskuje się jednolitą powłokę nanocząsteczek na powierzchni tkaniny z różnymi grupami funkcyjnymi. Powłokę można prowadzić w procesie in situ, w którym nanocząsteczki są formowane i natychmiast wyrzucane na powierzchnię tkaniny. To podejście zostało wykazane z nanosrebrem. Alternatywnie, proces sonochemiczny może być stosowany jako technika „rzucania kamieniami”, w którym wcześniej zsyntetyzowane nanocząsteczki są sonikowane w obecności tkaniny. Proces ten został przedstawiony za pomocą nanocząsteczek MgO i Al2O3, które zostały wyrzucone na powierzchnię za pomocą mikrodysz i silnie przylegały do tkaniny bez dodatkowego spoiwa. Zjawisko to tłumaczy się miejscowym topnieniem podłoża z powodu wysokiej szybkości i temperatury nanocząsteczek wyrzucanych na powierzchnię stałą przez sonochemiczne mikrodysze. Aktywność tkaniny wykończonej nanocząsteczkami przeciwbakteryjnymi badano na kulturach bakterii Gram-ujemnych i Gram-dodatnich. Znaczące działanie bakteriobójcze wykazano w obu przypadkach, nawet w niskim stężeniu, poniżej 1% wag. nanocząsteczek w tkaninie.
EN
In this study, a novel fibre-reactive nanoparticle was synthesised in three steps. First awater-soluble chitosan derivative, N-[(2-hydroxy-3-trimethylammonium)propyl] chitosanchloride (short for HTCC), was prepared by reacting chitosan with 2,3-poxypropyltrimethylammonium chloride. Second the HTCC was further modified by reacting it with N-(hydroxymethyl)-acrylamide to prepare a fibre-reactive chitosan derivative, O-methyl acrylamide quaternary ammonium salt of chitosan (short for NMA-HTCC), which can form covalent bonds with cellulose fibre under alkaline conditions. Thirdly NMA-HTCC nanoparticles were prepared by the ionotropic gelation reaction method. The particle size and TEM researches indicated that the globular NMA-HTCC nanoparticle with a size distribution of 15 - 50 nm was successfully prepared and presented good dispersity and stability. Then the NMA-HTCC nanoparticle was used for the textile finishing of cotton fabric. The modified cotton fabric demonstrated excellent durable wrinkle-resistance and antibacterial activity against Staphylococcus aureus and Escherichia coli, even after 50 repeated launderings. Moreover the shrinkage-resistance of the modified cotton fabric was distinctly improved, and the contact angle was slightly larger, while the whiteness and mechanical properties had not changed in an obvious way.
PL
W pracy syntetyzowano nanocząsteczkę reaktywną wobec włókien w trzech etapach. Najpierw przez poddanie reakcji chitozanu z chlorkiem 2,3-epoksypropylotrimetyloamoniowym otrzymano rozpuszczalną w wodzie pochodną chitozanu, chlorek N-[(2-hydroksy-3-trimetyloamino) propylo] chitozanu (HTCC). Następnie HTCC modyfikowano przez poddanie reakcji z N-(hydroksymetylo)-akryloamidem w celu wytworzenia reaktywnej wobec włókna pochodnej chitozanu, czwartorzędowej soli amonowej O-metyloakryloamidowej chitozanu (NMA-HTCC), która może tworzyć wiązania kowalencyjne z włóknami celulozowymi w warunkach alkalicznych. W kolejnym etapie przygotowano nanocząstki NMA-HTCC metodą jonotropowej reakcji żelowania. Badania rozmiarów cząstek i TEM wykazały, że kuliste nanocząstki NMA-HTCC o rozkładzie wielkości 15-50 nm miały dobrą dyspersyjność i stabilność. Następnie nanocząstki NMA-HTCC zostały użyte do wykańczania tkanin bawełnianych. Zmodyfikowana tkanina bawełniana wykazała się trwałą odpornością na gniecenie i działaniem przeciwbakteryjnym na bakterie Staphylococcus aureus i Escherichia coli, nawet po 50 powtarzanych praniach. Ponadto znacznie poprawiona została odporność na kurczenie się zmodyfikowanej tkaniny bawełnianej, a kąt zwilżania był nieco większy, natomiast biel i właściwości mechaniczne nie uległy zmianie w znaczący sposób.
EN
The aim of this study was to determine the antimicrobial properties of multilayer films containing a PHMG sulphanilate (polyhexamethylene guanidine sulphanilate). Three types of films were selected: monolayer and three-layer films (both containing biocide) and market foil. The antibacterial activity of polyethylene film with PHMG sulphanilate was verified based on the guidelines of ISO 22196: 2007 (E): Plastics - Measurement of antibacterial activity on plastic surfaces. The antimicrobial efficacy of the monolayer film against Escherichia coli and Staphylococcus aureus was very good, equalling 6.25 log (100%) and 6.02 log (100%), respectively. It means that a total reduction in bacteria on the surface tested was achieved. The antimicrobial efficacy of the three-layer film against Escherichia coli was satisfactory and equaled 1.32 log (95.2%). The antimicrobial efficacy of this film against Staphylococcus aureus was very good and equaled 6.02 log (100%). The antifungal activity of polyethylene film with PHMG sulphanilate was verified based on the guidelines of ASTM G21 - 96: Standard practice for determining the resistance of synthetic polymeric materials to fungi. The fungal growth of Aspergillus niger, Chaetomium globosum and Trichoderma viride on the monolayer and three layer films was also inhibited, which means that the biocide in the films also exhibits antifungal activities. For the market foil, poor antibacterial efficacy against the bacteria and no antifungal activity against the fungi tested was observed.
PL
Celem badań było określenie właściwości przeciwdrobnoustrojowych wielowarstwowych folii zawierających pochodną PHMG (sulfanilan poliheksametylenoguanidyny). Do badań wybrano trzy rodzaje folii: jednowarstwową i trójwarstwową (obie zawierające sulfanilan PHMG) i folię rynkową. Skuteczność antybakteryjna folii jednowarstwowej w odniesieniu do Escherichia coli i Staphylococcus aureus była bardzo dobra i wynosiła odpowiednio: 6,25 log (100%) oraz 6,02 log (100%), co oznacza całkowitą redukcję naniesionych komórek bakterii na badanej powierzchni. Skuteczność antybakteryjna folii trójwarstwowej w odniesieniu do Escherichia coli i Staphylococcus aureus była również dobra i wynosiła odpowiednio: 1,32 log (95,2%) oraz 6,02 log (100%). Ponadto, w badaniach zaobserwowano zahamowanie wzrostu pleśni: Aspergillus niger, Chaetomium globosum i Trichoderma viride zarówno na jednowarstwowej, jak i trójwarstwowej folii. Stwierdzono, że zawarty w foliach biocyd wykazywał również właściwości przeciwgrzybicze. Przeprowadzone badania potwierdziły, że zastosowanie pochodnej PHMG do produkcji folii zapewnia skuteczną ochronę przed wzrostem niepożądanych mikroorganizmów na badanych foliach.
EN
Chitosan/CuO nanocomposites (Chi/CuO) were prepared by facile and eco-friendly technique. The 2%w/v chitosan solution was mixed with 0.5 %w/w sodium tripolyphosphate (STPP), resulting in the formation of ionically crosslinked chitosan. The crosslinked chitosan was soaked in an aqueous solution containing 0.001, 0.01 or 0.1 mol/L CuSO4·5H2O for 24 hrs, in which the Cu2+ ions were absorbed into the chitosan network, forming as the chitosan/Cu2+ precursors. The chitosan/Cu2+ precursors were hydrothermally reacted in two different basic media, i.e. NaOH and NH4OH, at 100°C for 24 hrs, resulting in the nano-sized CuO crystals hydrothermally grew and embedded in the crosslinked chitosan matrix. The CuO grown in the NaOH possessed larger crystallite size and higher crystallinity than that in the NH4OH. In addition, the CuO crystallite size in the nanocomposites increased with the increase of initial concentration of Cu2+ starting agent due to the increase of Cu2+ quantity in the chitosan/Cu2+ precursors. The chitosan/CuO nanocomposites prepared by using 0.01 and 0.1 mol/L Cu2+ could exhibit the antibacterial activities after intimate contact with Staphylococcus aureus and Escherichia coli under JIS L 1902:1998 (Qualitative) test method, indicating their potential use as biocontrol agents.
EN
Since late 1930s copper has been recognized as an essential trace metal in living organisms. Copper(II) cation plays the role as a coordination center not only in the single-nuclear complexes, but also in the multinuclear coordination compounds with a particular emphasis on the polymers as ligands. The selected complex compounds of copper(II) with ligands which are organic and inorganic species have been characterized taking into account their physico-chemical properties. In addition, the complex compounds containing ligands such as Schiff ’s bases, hydrocarbons, organic bases, and also polycarboxylic anions: oxydiacetate, thiodiacetate, iminodiacetate and dipicolinate have been described considering their role in the biological systems. Nowadays tested coordination compounds of copper(II) have interesting antibacterial activities against bacteria strains that are antagonistic to the human. The antibacterial activity of copper(II) complex is stronger than some of the known antibacterial substances e.g. ciprofloxacin. In addition, copper(II) complex compounds exhibit a 64-fold greater antimicrobial properties than copper(II) chloride. Moreover, these compounds have antifungal and antioxidant properties. The activities of antibacterial, antifungal, and antioxidant complex compounds of copper( II) have been compared to the reactivities of these compounds with complexes used as reference substances, e.g. L-ascorbic acid, in the assay using nitrotetrazolium blue.
EN
Polyether ionophore antibiotics (ionophores) represent a large group of naturally- occurring lipid-soluble compounds isolated from actinomycetes strains of Streptomyces genus. Ionophores are able to form complexes with the metal cations, especially sodium and potassium, and transport them across the lipid membranes according to electroneutral or electrogenic transport mechanism. This process disturbs the intercellular Na+/K+ concentration gradient and intracellular pH, leads to the mitochondrial injuries, cell swelling, vacuolization and finally to programmed cell death (apoptosis). For this reason, ionophore antibiotics found commercial use in veterinary medicine as coccidiostatic agents and non-hormonal growth promoters. In addition to the industrial use of ionophores, some of them effectively and selectively inhibit properties of different cancer cells as well as enhance the anti-cancer effects of radio- and/or chemotherapy. In this group, particularly interesting is salinomycin because of its potent anti-microbial and anti-cancer activity, including efficiency against multi-drug resistant cancer cells and cancer stem cells. A very interesting direction of research is the chemical modification of ionophore antibiotics, which can lead to obtaining various derivatives with better biological activity and lower toxicity than those of the starting substances. Because biological activity of ionophore antibiotics and their derivatives is strictly connected with the ability to form characteristic pseudocyclic structures around the complexed cations (host-guest complex), it is also important to establish the detailed information on these structures. In this context, our review article is focused on the possible role of salinomycin and its derivatives in anti-microbial as well as anti-cancer therapy, and gives an overview of the properties of this antibiotic.
PL
Zbadano strukturę i wybrane parametry fizyko-mechaniczne, higieniczne i mikrobiologiczne podszewkowych skór obuwiowych z wypełnieniem opartym na naturalnych kompozytach mineralnych: zeolicie (MMZ), montmorylonicie (MMT) z dodatkiem preparatu na bazie poliheksametylenobiguanidy (PHMB). Badania wykazały poprawę badanych właściwości modyfikowanych próbek w odniesieniu do skór bez dodatku PHMB.
EN
The structure and the selected physical and mechanical, hygienic and microbiological parameters of footwear lining leather with filling based on natural mineral composite materials: zeolite (MMZ), montmorillonite (MMT) with an addition of a preparation based on polyhexamethylene biguanide (PHMB) were tested. The research has shown an improvement in the tested properties of the modified samples in relation to leather without PHMB.
EN
Silver nanoparticles (AgNPs) have been synthesized in the presence of Strawberry fruit extract (SBFE) at room temperature. The synthesized AgNPs was characterized by UV-vis spectroscopy, SEM, EDS, XRD, TEM and FTIR. The UV-vis spectra of the AgNPs show SPR band at 450 nm. TEM results indicate that AgNPs are spherical in shape and size range between 7–65 nm. Antibacterial activity of the synthesized AgNPs has been assessed against Pseudomonas aeruginosa and Bacillus licheniformis. The results show that AgNPs exhibit inhibitory effect and effect is a function of AgNPs concentration. The antibacterial activity of the prepared AgNPs has been compared with two antibiotics, amoxicillin and ciprofloxacin. It is found that the antibiotics perform better than AgNPs.
EN
The present study investigates the synthesis and characterization of iron oxide nanoparticles (Fe3 O4 -NPs) for their antibacterial potential against Bacillus cereus and Klebsiella pneumonia by modified disc diffusion and broth agar dilution methods. DLS and XRD results revealed the average size of synthesized Fe3 O4 -NPs as 24 nm while XPS measurement exhibited the spin-orbit peak of Fe 2p3/2 binding energy at 511 eV. Fe3 O4 -NPs inhibited the growth of K. pneumoniae and B. cereus in both liquid and soild agar media, and displayed 26 mm and 22 mm zone of inhibitions, respectively. MIC of Fe3 O4 -NPs was found to be 5 μg/mL against these strains. However, MBC for these strains was observed at 40 μg/mL concentration of Fe3 O4 -NPs for exhibiting 40–50% loss in viable bacterial cells and 80 μg/mL concentration of Fe3 O4 -NPs acted as bactericidal for causing 90–99% loss in viability. Hence, these nanoparticles can be explored for their additional antimicrobial and biomedical applications.
EN
Purpose: In this work our aim was to reveal the relationship between sodium alginate concentration and crosslinking level, also the ratio of release of the antibacterial additives: silver nanoparticles and metronidazole. Moreover, we examine obtained hydrogel as a potential dressing material for regenerative medicine. Design/methodology/approach: In the research specimens of hydrogels were tested to define their mechanical and physicochemical properties like antibacterial activity against gramnegative Escherichia coli and gram-positive Staphylococcus aureus, viscosity and conductivity. Findings: The concentration of alginate and presence of antibacterial additives influence on the crosslinking level. Mechanical properties of hydrogels are similar to human skin. Only hydrogels with addition of metronidazole and AgNP inhibits bacteria growth after 18 h. In case of gram-negative Escherichia coli both of the aseptic additives inhibits bacteria growth, but sodium alginate hydrogel with silver nanoparticles gives better results in tests with grampositive Staphylococcus aureus . Research limitations/implications: The presence of metronidazole in hydrogel, especially its incorporation and binding with mannuronic and guluronic acid residues must be clarified in more advanced research. Practical implications: Obtained results shows that sodium alginate hydrogels with 0.1mg/ml of alginate, due to its properties are proper as a dressing material. Based on the results, and more advanced tests with metronidazole, we can consider dressing design. Originality/value: Unique value of this work is that we completed the gap in knowledge about the relation of crosslinking level and mechanical properties with are crucial to proper tissue healing and addition of popular aseptic agents.
EN
In this study, an attempt was made to investigate the antimicrobial activity on polypropylene (PP) hydroentangled nonwoven fabrics coated with transition metal oxides. After etching the nonwoven fabrics with RF plasma, nano-scale coatings of ZnO and CuO were done using the KrF excimer based pulsed laser deposition technique (PLD). Morphological and antimicrobial studies were carried out to elucidate the mechanism of antibiocidal behaviour of the coated fabrics. Results showed significant antibacterial activity of ZnO and CuO coated PP hydroentangled nonwovens with a better activity against gram positive S.aureus than gram negative E.coli. Inherently non-toxic, PP has excellent chemical resistance and the use of specialised PP fibres for hydroentangled nonwovens could offer scope in addition to metal oxide coatings; nano-scale biological materials such as enzymes and drugs could add specific functionality for their use as medical textiles.
PL
W pracy podjęto próbę zbadania aktywności przeciwdrobnoustrojowej polipropylenowych włóknin pokrytych tlenkami metali. Przeprowadzono badania morfologiczne i przeciw- drobnoustrojowe powlekanych włóknin. Wyniki wykazały znaczną aktywność antybakteryjną włóknin pokrytych ZnO i CuO, przy czym wyższą aktywność antybakteryjną zaobserwowano wobec bakterii Gram-dodatnich (Staphylococcus ureus), niż wobec Gram-ujemnych (Escherichia coli). Stwierdzono, że zastosowanie nietoksycznego polipropylenu, który charakteryzuje się bardzo dobrą odpornością chemiczną, do wytwarzania włóknin powlekanych tlenkami metali pozwala na otrzymanie funkcjonalnych produktów medycznych.
PL
Głównym celem pracy jest badanie właściwości biologicznych kompozytów polimerowych otrzymanych w procesie wytłaczania i wtrysku. Do badań użyto medycznego polietylenu o wysokiej gęstości, HDPE. Jako fazę modyfikującą zastosowano nanocząstki srebra, nAg. Właściwości biologiczne materiałów zostały ocenione w wyniku testu cytotoksyczności, żywotności/proliferacji komórek oraz testu działania przeciwbakteryjnego. Na podstawie otrzymanych wyników stwierdzono, że materiały kompozytowe zawierające nanocząstki srebra nie wykazują działania cytotoksycznego wobec komórek osteoblastycznych i fibroblastów ludzkich. Dodatek nanosrebra nie powoduje działania przeciwbakteryjnego zarówno wobec bakterii Gram-dodatnich jak i Gram- -ujemnych. Zwiększanie ilości użytego modyfikatora nie zwiększa działania przeciwbakteryjnego. Komórki osiadłe na próbkach kontrolnych, polimerowych i kompozytowych miały prawidłowy, wrzecionowaty kształt. Zasiedlały ich powierzchnie w dużych ilościach, w sposób równomierny. Zaobserwowano wzrost ilości komórek na powierzchni próbek wraz z zawartością nanocząstek srebra, co związane jest ze wzrostem chropowatości powierzchni.
EN
The main aim of this research is the examination of biological properties of polymer composites obtained in the process of extrusion and injection molding. It has been decided to use high-density medical polyethylene (HDPE) as a matrix, which afterwards has been modified with silver nanoparticles. Biological properties have been examined during cytotoxicity tests, cell viability/cell proliferation tests and antibacterial activity tests. Based on obtained results, it has been proved that composites with addition of silver nanoparticles do not cause cytotoxic effect on osteoblast cells and human fibroblasts, concerning both Gram-positive and Gram-negative bacteria. The increasing amount of modifier does not increase antibacterial activity. The control samples were characterized by high proliferation rate and evenly distributed cells of proper, spindle-like shape. The surface was settled with cells evenly and densely. It has been observed that amount of silver nanoparticles affects cells proliferation what is related to increasing surface roughness.
PL
Lizozym to białko enzymatyczne, powszechnie występujące w przyrodzie, charakteryzujące się wieloma użytecznymi właściwościami, które umożliwiają wszechstronne jego wykorzystanie. Obecnie praktyczne zastosowanie enzymu dotyczy monomeru, a już wkrótce zapewne także jego zmodyfikowanej postaci. W porównaniu z monomerem zmodyfikowany lizozym wykazuje bowiem zdecydowanie większe możliwości przeciwdrobnoustrojowego działania. Dzieje się tak dzięki pojawieniu się w nim nowej, specyficznej, antybakteryjnej aktywności wobec drobnoustrojów Gram-ujemnych. Wykazuje wiele nowych właściwości, istotnych z punktu widzenia medycznego, farmaceutycznego i weterynaryjnego. Można się zatem spodziewać, że zmodyfikowany enzym będzie praktycznie wykorzystywany nie tylko w przemyśle spożywczym, ale także w medycynie, weterynarii i farmakologii. Obecnie prowadzone badania pozwoliły na opracowanie oryginalnych sposobów modyfikacji lizozymu, umożliwiających wytworzenie produktu wysokiej jakości. Niektóre z tych metod, np. metodę termiczną, termiczno-chemiczną, chemiczną czy membranową, w prosty sposób można przenieść z warunków laboratoryjnych do skali półtechnicznej czy nawet przemysłowej.
EN
Lysozyme is an enzyme protein, commonly found in nature, characterized by many useful properties that allow its versatile use. The current practical application of the enzyme concerns monomer, and soon, also its modified forms. Wider use should be linked just with the possibility of using the modified enzyme and not only in the food industry but also in medicine, veterinary medicine and pharmacology. Current research allowed developing original methods to modify lysozyme, enabling manufacture of a high quality product. Some of them, like thermal, thermalwidzenia -chemical, and chemical or membrane method are easy to be transferred from the laboratory conditions to the pilot or even industrial scale. The aim of this study was to present the methods of obtaining and modifying lysozyme causing its oligomerization, the methods of assessment of physicochemical properties of the modified lysozyme and its antibacterial action and the possibility of its practical application.
PL
Celem prowadzonych badań było określenie aktywności przeciwbakteryjnej in vitro bioaktywnych szkieł dotowanych Mg, Sr i Au. Przedstawiono badania zmodyfikowanych bioszkieł zawierających wybrane pierwiastki wprowadzone dla podwyższenia bioaktywności, które mogą wspomagać przebieg procesów fizjologicznych kościotworzenia i wykazywać działanie przeciwbakteryjne. Obecność magnezu w składzie biomateriału zwiększa jego bioaktywność. Stront wpływa na lepszą proliferację komórek kostnych. Złoto należy do grupy „ultraelementów” działających przeciwbakteryjnie oraz aktywuje procesy metaboliczne poprzez oddziaływanie na enzymy. Silany użyte podczas syntezy bioszkieł metodą zol-żel, także mogą zwiększać ich bioaktywność. Materiał odniesienia stanowiło bioszkło P5-VS zawierające 70% mas. SiO2, 5% mas. P2O5 oraz 25% mas. CaO. Bioszkła P5-VS-1_Mg i P5-VS-1_Sr, o takim samym składzie jak P5-VS wytworzono zastępując 1% mas. CaO odpowiednio MgO lub SrO. W przypadku bioszkieł P5-VS-Au_r-r i P5-VS-Au_nzk nanocząsteczki złota były dodane w ilości 0,00065% mas. i 0,002% mas. odpowiednio jako: roztwór koloidalny lub niejonowe złoto koloidalne. Właściwości fizykochemiczne wytworzonych bioszkieł obejmujące morfologię powierzchni, a także ich bioaktywność po kontakcie z roztworem symulującym osocze oraz wyniki cytotoksyczności zostały przedstawione w innym artykule. Stwierdzono, że bioszkła w kontakcie z płynem symulującym osocze (SBF) są bioaktywne oraz nie oddziałują cytotoksycznie na komórki L929. Wyniki badań in vitro aktywności przeciwbakteryjnej wytworzonych bioszkieł wykazały ich wyższą aktywność w stosunku do szczepu Staphylococcus aureus niż Pseudomonas aeruginosa. Wzrost mikroorganizmów najbardziej hamowało bioszkło P5-VS-1_Sr. Bioszkło P5-VS bez udziału Mg, Sr lub Au wykazywało najsłabsze działanie przeciwbakteryjne.
EN
The aim of this study was to determine in vitro antibacterial activity of bioactive glasses doped with Mg, Sr and Au. Authors showed tests of modified bioglasses containing selected elements incorporated to the composition in order to increase bioactivity, which could contribute to physiological processes of osteogenesis and exhibit bactericidal activity. The presence of magnesium in the composition of the biomaterial enhances its bioactivity. Strontium improves the proliferation of bone cells. Gold belongs to the group of “ultra-elements” which show antibacterial activity and activate metabolism by acting on enzymes. The silane used for the synthesis of sol-gel bioglasses may also increase bioactivity. Bioglass P5-VS containing 70 wt% of SiO2 and 25 wt% of CaO and 5 wt% of P2O5 was a reference material. Bioglasses P5-VS-1_Mg and P5-VS-1_Sr with the same composition as P5-VS were obtained by substituting 1 wt% of CaO by MgO or SrO respectively. In the case of bioglasses P5-VS-Au_r-r and P5-VS- -Au_nzk nanoparticles of Au were added in the amount of 0.00065 wt% and 0.002 wt% as colloidal solution or nonionic colloidal gold respectively. Physical and chemical properties of sol-gel bioactive glasses including grain morphology and bioactivity in simulated body fluid and the results of cytotoxicity were presented in a previous publication. It was found that bioglasses were bioactive in contact with simulated body fluid (SBF) and were not toxic on L929 cells in vitro. The results of in vitro antibacterial activity studies of obtained bioglasses showed higher activity against strain of Staphylococcus aureus than Pseudomonas aeruginosa. The growth of microorganisms was inhibited in the most effective way by the bioglass P5-VS-1_Sr. The P5-VS bioglass without Mg, Sr or Au shows the weakest bactericidal effect.
19
Content available remote Specifics of pesticides effects on the phytopathogenic bacteria
EN
The data concerning the effects of pesticides of different nature on the phytopathogenic bacteria was examined and summarized. Without extensive research on the mechanisms of interaction between pathogenic bacteria and pesticides in the literature review a similar message about microorganisms of soil and phyllosphere are included. The bacteria can be suppressed permanently by pesticides with a mechanism of action that universally affects biological processes in living systems. Long-term storage, ease of use and fast visible effect are the advantages of synthetic pesticides remedies. But chemical pollution, shifts in the balance of ecosystems, unpredictable effects of chemical pesticides on non-target objects are the drawbacks. Stimulation of resistance response in plants is unifying factor for all types of biopesticides. This is realized through localization of the pathogen during infection, blocking its further penetration, distribution and reproduction. The results of the study of effects of plant protection products on the phytopathogenic bacteria of main crops are described. Among all tested pesticides, thiocarbamate fungicides demonstrated significant inhibitory action on phytopathogens, but their effect may be neutralized by other constituents of multicomponent preparations. Triazole fungicides affect the causative agents of bacterioses of crops at a dose of more than 1% of the active substance in the nutrient medium. Insecticides and herbicides have little or no effect on phytopathogenic bacteria; however they can enhance morphological dissociations of some Pseudomonas strains, thereby increasing their ability to survive. The disadvantage of many biopesticides against phytopathogenic microorganisms is the difference between their efficacy in vitro and in vivo that is why the desired result is not achieved in field condition. In addition, biological pesticides often lose their activity causing the problem of constant search for new active antagonists. The fact that the sensitivity of phytopathogenic bacteria to pesticides is strain-dependent should be considered in practice, particularly, assessment of the antibacterial action of various preparations should not be limited to a single bacterial strain.
20
Content available remote Hemostatic, Resorbable Dressing of Natural Polymers-Hemoguard
EN
Investigations are presented for the preparation of a model hemostatic dressing that would exhibit an adequate hemostatic capacity in injuries and surgical wounds, an antibacterial activity to prevent primary and secondary infections, and offer safety in use. The Hemoguard dressing has been designed as a powder prepared from the complex chitosan/alginate Na/Ca in the form of micro- and nano-fibrids. Useful antibacterial and hemostatic properties of Hemoguard, which would qualify the material as first aid dressing and a temporary protection of injury wounds in field conditions, were assessed. Biocompatibility of the dressing was confirmed by biological in vitro examinations.
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