Papers by Keyword: Anti-Bacteria

Abstract: Zinc oxide nanoparticles (ZnO-NP) were successfully synthesized from aloe vera extract and zinc sulphate as zinc precursor. Characterizations of the ZnO-NP were performed using UV–Vis spectrophotometer, XRD, FESEM and TEM analysis. The absorption peak from UV–Vis was at 380 nm while the XRD diagram displays high purity ZnO-NP. FESEM and TEM analysis showed agglomerated particles with a wide size distribution range. Polymerase chain reaction (PCR) analysis of Xanthomonas oryzae pv. oryzae (Xoo) pathotype 0.0 generated a product with the size of 230 bp similar to in silico PCR results, verifying the pathotype on molecular level. Subsequently, the antimicrobial activities of the ZnO-NP against Xoo pathotype 0.0 were assessed. Xoo (10⁸ cfu/ml) were grown in LB broth supplemented with various concentrations of ZnO-NP. Collection of samples were done at 24 hours, 48 hours and 72 hours of incubation, grown on LB agar and observed for bacterial growth. Colony forming unit (cfu/ml) values revealed the number of viable cells decreased with high concentrations of ZnO-NP whereas minimal inhibition was observed at lower ZnO-NP concentrations. At lower bacteria cfu/ml (10³ cfu/ml), it was found that at 24 hours incubation, ZnO-NP gave comparable antibacterial effects to commercial ZnO-NP and commercial non-nanoZnO after exposure for 1 hour. However, the antimicrobial effects decreased after 48 hours. It was also noted that the ZnO-NP provide better suppression of bacterial growth at lower bacterial concentration.

Abstract: Mangosteen peel powder is one of the most important bio-antioxidants. Adding mangosteen peel powder as filler into natural rubber latex compound for latex glove film formation via dipping process can help the green anti-microbial properties. The physical (smoothness and thickness of film) and mechanical properties (tensile strength and elongation at break) of latex film are still good. Therefore, adding mangosteen peel powder into natural rubber latex gloves can reduce the anti-allergic and antimicrobial on the film surface. Mangosteen peel powder ground by rapid mill is fine particle and high surface area 2.4216 m²/g suitable for homogeneous and compatible for adding into natural rubber latex compound. Ceramic hand mold was dipped into the Ca (NO₃)₂ coagulant only 3 seconds, then dipped into the natural rubber latex compounds added mangosteen peel powder for 15 seconds, withdrawn hand mold slowly, cured in the oven at 120°C for 30 min, then dried at room temperature, and casted it off the hand mold. The obtained natural latex glove films added mangosteen peel powder are smooth, clear, and thin film surface, the highest elongation at break 803.2711 ± 31.6477%, good tensile strength 30.2933 ± 6.0218 MPa, dense film without water leakage, and good contact angle.

Abstract: PR-1 (pathogenesis-related proteins) family has been described one of the most important families among the 17 PR groups in many plant species in defense with oomycetes, fungi, bacteria, orviruses, used as a marker of the capacity of defense in PRs. Though some independent studies have demonstrated that antifungal activity is clearly associated with purified, over-expressed PR-1 protein or PR-1 proteins-containing transgenic plants, the biological functions of PR-1 proteins remains basically blur. The PR-1proteins are encoded by multi-gene families in plants based on the presence of 22 and 32 PR-1 genes in the finished Arabidopsis and rice genomes, respectively. The PR-1 proteins were found secreted either on resisting pathogens, or upon defense signaling, later the PR-1 proteins were also demonstrated in various developmental healthy plants tissues, like tobacco floral tissues and leaves, suggesting that these proteins serve essential functions in plant life, whether in defense or not.

Abstract: Herein, we proposed a novel, facile method for flocculation of Saccharomyces cerevisiae cells via nanoZnO. According to results, the presence of nanoZnO could significantly facilitate the flocculation of the yeast cells without damage the cellular morphology. Notably, the yeast cells flocculated by using nanoZnO displayed certain antibacterial property. Moreover, the cell activity was almost remained after flocculated by this method.

Abstract: The materials structures from the regenerated bamboo fiber (namely bamboo pulp fiber), the functional polyester fiber (UV-resistance polyester) and the profiled polyester were analyzed. 28 pieces of fabrics through blending, mixing and matching were designed and woven. The properties including thermal-wet comfort (such as air permeability, moisture permeability and water absorbance etc.) and other functions (such as UV-resistance and anti-bacteria) on those fabrics were tested, discussed and analyzed. The result is that when the radio of the functional polyester reach 45～50 %, the radio of regenerated bamboo fiber in 50 %, the structure is 3/1 or 2/1 twill weave，the double-layer-like tightness woven fabrics avoiding finished and bad hand feel will perform cool , UV-resistance, anti-bacteria multi-function. It will be a good choice to use these fabrics in summer shirts. It will give some references to the development of summer new functional products.

Abstract: TaN–Cu and TaN-Ag nanocomposite films were deposited by reactive co-sputtering on Si. The films were then annealed using RTA (Rapid Thermal Annealing) at 400 °C for 2, 4, 8, 15 minutes respectively to induce the nucleation and growth of metal particles in TaN matrix and on film surface. The samples were then tested for their anti-bacterial behaviors against Gram-negative and Gram-positive bacteria. The results were compared with the solubility of Ag and Cu in a buffer solution. Under similar ion concentrations, it is concluded that Ag ion or TaN-Ag is more effective against E. Coli (Gram-negative), while Cu ion or TaN-Cu is more effective against Staphylococcus aureus (Gram-positive).

Abstract: Percutaneous type of orthopedic and dental implants requires not only a good adhesion with bone, but also the ability to form good attachment and seal with connective tissues and skins. Currently, the skin-seal of such implants still remains as a problem to be resolved. Electrochemical processing was used to modify the surface of titanium implants in order to improve the ability of anti-bacteria infection and skin seal around the implants by synthesizing a fluoridated calcium phosphate thin film on titanium substrate. The surface of titanium was cathodically treated in an electrochemical cell. A thin film of about 80 nm thickness was deposited on the titanium surface by controlling the treatment parameters. The dense and gel-like film was composed of calcium phosphate and fluorine ions. Fluorine ion has the anti-bacteria property and could help to improve the skin seal around the percutaneous device. The electrochemical method of fluoridated calcium phosphate thin film synthesis will provide an alternative method for surface treatment of orthopedic and dental implants.

Abstract: Due to excellent photocatalytic and optical properties of titanium dioxide (TiO2), it has been applied in several products such as food packaging plastics, materials for vehicles or for buildings and sunscreen-protecting cosmetics. In this present work, the synthesized as well as commercial TiO2 was coated onto a household curtain fabric for anti-microbial and ultraviolet (UV) shielding functions. The coating was performed by inducing the deposition of TiO2 layer from the Ti precursor onto the fabric surface pre-treated with silane adhesive agent so as to improve the adhesion. Ag nanoparticles were also incorporated in some samples to further improve the antibacterial function. Anti-bacterial activities of the coated fabric were evaluated by standard qualitative test (the Kirby-Bauer test (AATCC 147)). Efficiency for UV shielding was evaluated by measuring a UV-Vis reflection of the coated fabrics both before and after subjecting to several washing cycles. The result showed that the TiO2-coated fabrics developed had potential as antibacterial and UV shielding for the curtain industry.