Yazar "Tan, Gamze" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • Küçük Resim Yok
    Öğe
    Antioxidative and antiproliferative effects of propolis-reduced silver nanoparticles
    (Techno-Press, 2021) Tan, Gamze; Ilk, Sedef; Foto, Fatma Z.; Foto, Egemen; Saglam, Necdet
    In this study, phytochemicals present in Propolis Extract (PE) were employed as reducing and stabilizing reagents to synthesize silver nanoparticles. Three propolis-reduced silver nanoparticles (P-AgNPs1-3) were synthesized using increasing amounts of PE. P-AgNPs were treated with different cancer cells -lung (A549), cervix (HeLa) and colon (WiDr) for 24, 48 and 72 h to evaluate their anti -proliferative activities. A non-cancerous cell type (L929) was also used to test whether suppressive effects of P-AgNPs on cancer cell proliferation were due to a general cytotoxic effect. The characterization results showed that the bioactive contents in propolis successfully induced particle formation. As the amount of PE increased, the particle size decreased; however, the size distribution range expanded. The antioxidant capacity of the particles increased with increased propolis amounts. P-AgNP1 exhibited almost equal inhibitory effects across all cancer cell types; however, P-AgNP2 was more effective on HeLa cells. P-AgNPs3 showed greater inhibitory effects in almost all cancer cells compared to other NPs and pure propolis. Consequently, the biological effects of P-AgNPs were highly dependent on PE amount, NP concentration, and cell type. These results suggest that AgNPs synthesized utilizing propolis phytochemicals might serve as anti -cancer agents, providing greater efficacy against cancer cells.
  • Küçük Resim Yok
    Öğe
    Green Synthesis and Biogenic Materials, Characterization, and Their Applications
    (Springer Science and Business Media B.V., 2019) Tan, Gamze; İlk, Sedef; Emul, Ezgi; Asik, Mehmet Dogan; Sam, Mesut; Altindag, Serap; Birhanli, Emre
    Modern nanotechnology, together with the help of pharmaceutical and biomedical science, deals with improving new drug delivery systems in order to cure many diseases including cancer. Thus, nanotechnology has generated a potential influence in several disciplines of medicine including cardiology, endocrinology, immunology, oncology, pulmonology, and ophthalmology. Till date, very little work has been done regarding the positive or beneficial influences of nanomaterials on plant species. However, nanotechnology has the potential for creating new materials to develop new methods or tools for incorporation of fictional nanoparticles into the plants to improve their physiological, morphological, or other related characters. In natural environment, plants and microorganisms like bacteria, algae, yeasts, and fungi have the ability to produce nanosized materials as part of their metabolism. Synthesis of nanoparticles by microorganisms has been arisen as prominent research area in nanoscience day by day. In general, microorganisms produce inorganic nanoparticles in intracellular and/or extracellular way. Microbial production of metallic nanoparticles, especially silver, is achieved by reduction mechanisms of metal ions, while they generate silver nanoparticles as part of their metabolism due to their defense mechanism. Bio-produced silver nanoparticles are also applied for enhanced antimicrobial properties in combination with commercial antibiotics against pathogenic microorganisms. Their antimicrobial and cytotoxic effects are evaluated within this chapter. © 2019, Springer Nature Switzerland AG.
  • Küçük Resim Yok
    Öğe
    Investigation the potential use of silver nanoparticles synthesized by propolis extract as N-acyl-homoserine lactone-mediated quorum sensing systems inhibitor
    (Tubitak Scientific & Technological Research Council Turkey, 2020) Ilk, Sedef; Tan, Gamze; Emul, Ezgi; Saglam, Necdet
    Background/aim: Quorum sensing (QS) is a chemical communication process that bacteria use to regulate virulence. Inhibition of QS (antiQS) overcomes the pathogenicity of bacteria. Silver nanoparticles (AgNPs) have been used as antimicrobials against pathogens, but have not been used against QS-mediated bacterial infection. Also, studies have been carried out on the inhibitory effects of propolis based structures on pathogen growth, but no studies have been found on their potential use as QS inhibitor. The present study aims to investigate the synthesis and characterization of silver nanoparticles (AgNPs) reduced with propolis extract (P-AgNPs) and evaluation of their antimicrobial and, for the first time, antiQS activity. Materials and methods: P-AgNPs were synthesized using with different volumes (1, 2.5 and 5 mL) of propolis extract (PE) by biological method via reduction of silver nitrate. Synthesized P-AgNPs were characterized in terms of hydrodynamic, chemical, morphological, physical, and antioxidant properties. Disc diffusion and flask incubation assays were used to evaluate the antimicrobial effect against Gram-negative bacteria (Escherichia coli, Proteus mirabilis, Proteus vulgaris, Salmonella typhimurium, Enterobacter aerogenes, Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus, Streptococcus mutans, Bacillus thuringiensis) and QS-regulated biofilm activity against biosensor strain Chromobacterium violaceum CV026. Results: AgNPs were successfully synthesized by biological method via PE. The violacein pigment production based on the QS system was greatly inhibited by the P-AgNPs (inhibition zones: 16.22-21.48 mm and violacein inhibition: 63.16 +/- 2.4-75.24 +/- 3.5 %) without interfering with the growth of bacteria, which is the first report on the antiQS effect of P-AgNPs. Conclusion: Our results suggest that P-AgNPs may be potentially used to inhibit bacterial physiological processes due to the signal molecules regulates important collective behavior of bacteria. The development of such nontoxic biomaterials may have great potential to evaluate for the new medicinal substance that inhibits the pathogenic biofilms.