Yazar "Yildirim, N." seçeneğine göre listele

Listeleniyor 1 - 5 / 5
  • [ X ]
    Öğe
    Antibacterial Effects of Some Fermented Commercial and Homemade Dairy Products and 0.9% Lactic Acid against Selected Foodborne Pathogens
    (Academic Journals Inc, 2011) Yesillik, S.; Yildirim, N.; Dikici, A.; Yildiz, A.; Yesillik, S.
    In this study, the antibacterial effects of homemade yoghurt, commercial yoghurt, commercial kefir and probiotic yoghurt on viability of Salmonella typhimurium (ATCC 14028), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923) was investigated by using disc diffusion method. Antibaterial effects of the samples were tested at 24, 48 h and the 7 day intervals. Homemade yoghurt showed the maximum antibacterial effect against the pathogens. It was determined that the most sensitive pathogenic bacteria to dairy products were Salmonella typhimurium whereas the least sensitive pathogen was Pseudomonas aeruginosa. Comparing to the antimicrobial effect of 0.9% lactic acid which was used as positive control, our results concluded that the bacteria found in fermented dairy products have an antibacterial activity and this activity is not caused by only lactic acid.
  • [ X ]
    Öğe
    Antioxidant enzymes activities in rat kidney after cold stress exposure
    (Wiley-Blackwell Publishing, Inc, 2009) Yildirim, N. Cikcikoglu; Yurekli, M.; Matpan, F.; Yildirim, N.
    [Abstract Not Available]
  • [ X ]
    Öğe
    IN VITRO ANTIMICROBIAL EVALUATION OF COMMERCIAL TEA EXTRACTS AGAINST SOME PATHOGEN FUNGI AND BACTERIA
    (Inst Materials Physics, 2010) Yildirim, N.; Bekler, F. Matpan; Yildirim, N. Cikcikoglu; Dikici, A.
    The in vitro antimicrobial activity of crude ethanol, methanol, hexane and aqueous extracts of commercial tea types such as fennel (Foeniculum sp.), senna (Cassia sp.), basilrosemary (Ocimum sp.-Rosmarinus sp), daisy (Bellis sp.) and sage (Salvia sp) against pathogen fungi (Colletotrichum coccodes, Epicoccum nigrum, Scopulariopsis brevicaulis) and foodborne pathogen bacteria (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Bacillus cereus, Klebsiella pneumoniae, Enterobacter sp.) were investigated with disk diffusion method. Senna (Cassia sp.) exhibed the most effective antimicrobial activity in both ethanolic and methanolic extracts. The best antimicrobial effect (30.6 mm) against E. nigrium was seen in methanolic senna (Cassia sp.) extract. The results of the study indicate that commercial tea types have showed various levels of antimicrobial activity depend on the type of solvent used in the extraction procedure.
  • [ X ]
    Öğe
    In vitro antimicrobial evaluation of commercial tea extracts against some pathogen fungi and bacteria
    (Inst Materials Physics, 2010) Yildirim, N.; Matpan Bekler F.; Cikcikoglu Yildirim, N.; Dikici A.
    The in vitro antimicrobial activity of crude ethanol, methanol, hexane and aqueous extracts of commercial tea types such as fennel (Foeniculum sp.), senna (Cassia sp.), basil-rosemary (Ocimum sp.-Rosmarinus sp), daisy (Bellis sp.) and sage (Salvia sp) against pathogen fungi (Colletotrichum coccodes, Epicoccum nigrum, Scopulariopsis brevicaulis) and foodborne pathogen bacteria (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Bacillus cereus, Klebsiella pneumoniae, Enterobacter sp.) were investigated with disk diffusion method. Senna (Cassia sp.) exhibed the most effective antimicrobial activity in both ethanolic and methanolic extracts. The best antimicrobial effect (30.6 mm) against E. nigrium was seen in methanolic senna (Cassia sp.) extract. The results of the study indicate that commercial tea types have showed various levels of antimicrobial activity depend on the type of solvent used in the extraction procedure.
  • [ X ]
    Öğe
    Temperature dependence of current-voltage characteristics of Sn/p-Si Schottky contacts
    (Elsevier, 2008) Aydin, M. E.; Gullu, O.; Yildirim, N.
    The current-voltage (I-V) characteristics of Sn/p-Si Schottky barrier diode have been measured over a wide range of temperature (80-300 K) and interpreted on the basis of thermionic emission mechanism by merging the concept of barrier inhomogeneities through a Gaussian distribution function. The analysis has revealed an anomalous decrease of apparent barrier height Phi(b0), increase of ideality factor n, and nonlinearity of the activation energy plot at lower temperatures. A Phi(b0) versus 1/T plot has been drawn to obtain evidence of a Gaussian distribution of barrier heights, and values of 0.97 eV and 0.084 V for the mean barrier height Phi(b0) and standard deviation sigma(0) have been obtained, respectively, from this plot. A modified ln(I-0/T-2)-(q(2)sigma(2)/2k(2)T(2)) versus 1/T plot gives Phi(b0) and Richardson constant A** as 0.95 eV and 15.6 A cm(-2) K-2, respectively. It can be concluded that the temperature dependent I-V characteristics of the Sn/p-Si Schottky barrier diode can be successfully explained on the basis of a thermionic emission mechanism with Gaussian distribution of the barrier heights. We have also discussed whether or not the junction current has been connected with thermionic field-emission mechanism. (C) 2007 Elsevier B.V. All rights reserved.