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Öğe Antibacterial effects of Turkish pollen and propolis extracts at different concentrations(M H SCHAPER GMBH CO KG, 2004) Ozcan, M; Sagdic, O; Ozkan, GThe antimicrobial activity of pollen and propolis extracts was investigated against 20 species of bacteria. A wide range of antibacterial activity was shown. Only the growth of B. amyloliquefaciens, B. megaterium, E coli and E coli 01 57:H7 was not affected at all concentrations of both extracts. Among the bacteria tested, the most sensitive were S. aureus for a 1/5 level of pollen extract and L. monocytogenes for a 1/10 level of propolis extract. The most active extract level on growth of bacteria was a 1/10 concentration of propolis. At the other extreme, the inhibitory effects of propolis extract concentrations on growth of bacteria were higher when compared with the respective pollen extract concentrations. The least active concentrations towards the tested bacteria were the 1/50 level of pollen extract and the 1/1000 level of propolis extract. In conclusion it is to be stated that the extracts could be used as antibacterial agents.Öğe Antioxidant and antibacterial activities of Turkish endemic Sideritis extracts(CONSEJO SUPERIOR INVESTIGACIONES CIENTIFICAS-CSIC, 2005) Ozkan, G; Sagdic, O; Ozcan, M; Ozcelik, H; Unver, ASideritis species are traditionally used as teas, flavoring agents and for medicinal purposes in Turkey. In this study, the antioxidant and antimicrobial activities of Sideritis condensata Boiss. & Heldr. (SC) and Sideritis eryhrantha var. erythrantha Boiss. & Heldr. (SE) endemic species' extracts of Lamiaceae were determined, These extracts were investigated for antibacterial activity by using the agar diffusion method against 15 species of bacteria: Aeromonas hydrophila, Bacillus cereus, Enterobacter aerogenes, Enterococcus faecalis, Escherichia coli, Escherichia coli O157:H7, Klebsiella pneumoniae, Mycobacterium smegmatis, Proteus vulgaris, Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus and Yersinia enterocolitica. Statistical differences within bacteria were significant at p < 0.05. SC extract was more effective than the other. At all concentrations, although the most sensitive bacteria was P aeruginosa, the most resistant bacteria were E. faecalis for SC extract and E. faecalis, S. aureus for SE extract. Total phenolics, radical scavenging activity by 1, 1 -diphenyl-2-picrylhydrazyl (DPPH) method and the antioxiclant capacities by the formation of phosphomolybdenum complex method of the extracts were determined. The total phenolics were found as 247.62 +/- 1.91 mg gallic acid equivalent (GAE)/g in SC extract and 217.61 +/- 0.95 mg GAE/g in SE extract of dried weight. At 100 ppm concentration, the free radical scavenging activities of SC and SE extracts were found as 72.01 +/- 1.93 and 71.48 +/- 1.95%, respectively. The antioxidant activities by phosphomolybdenum method of SC and SE extracts were 279.37 +/- 3.61 and 146.11 +/- 3.11 mg/g dried extract.Öğe Characterisation of essential oil plants from Turkey by IR and Raman spectroscopy(ELSEVIER SCIENCE BV, 2005) Schulz, H; Ozkan, G; Baranska, M; Kruger, H; Ozcan, MThe essential oils obtained from various plant species (genera: Origanum, Satureja, Salvia, Sideritis, Thymus, Calamintha, Lavandula, Ziziphora and Thymbra) collected in Turkey were studied by two complementary methods, ATR/FT-IR and NIR-FT-Raman spectroscopy. The vibrational spectra of both techniques obtained from the hydro-distilled essential oils of the air-dried plant material present characteristic key bands of the individual main volatile components (e.g. carvacrol, thymol, p-eymene, gamma-terpinene, camphor, 1,8-cineole, alpha- and beta-pinene). Applying principal component analysis (PCA) to these spectral data, a clear discrimination of the different species can be frequently achieved. Hierarchical cluster analysis provides a fast, easy and reliable approach for chemotaxonomy characterisation. Both vibrational techniques described in this study have the potential to replace existing standard methods used for quality control purposes and continuous evaluation of distillation processes. (c) 2005 Elsevier B.V. All rights reserved.Öğe A study on inhibitory effects of Sigla tree (Liquidambar orientalis Mill. var. orientalis) storax against several bacteria(WILEY, 2005) Sagdic, O; Ozkan, G; Ozcan, M; Ozcelik, SIn this study, Sigla (Liquidambar orientalis Mill.) storax (styrax) was investigated for antibacterial activity against Aeromonas hydrophila, Bacillus amyloliquefaciens, B. brevis, B. cereus, B. megaterium, B. subtilis, Corynebacterium xerosis, Enterobacter aerogenes, Enterococcus faecalis, Escherichia coli, E. coli O157:H7, Klebsiella pneumoniae, Listeria monocytogenes, Micrococcus luteus, Mycobacterium smegmatis, Proteus vulgaris, Pseudomonas aeruginosa, P. fluorescens, Staphylococcus aureus and Yersinia enterocolitica. The storax was dissolved in absolute ethanol and was tested at concentrations of 10.0%, 1.0%, 0.4%, 0.2% and 0.1%. Pure ethanol was used for the control. The antibacterial activity of the Sigla storax was determined by using the agar diffusion method. The growths of A. hydrophila, B. amyloliquefaciens, B. megaterium, E. coli, E. coli O157:H7, L. monocytogenes and Y. enterocolitica were not inhibited by any of the concentrations of Sigla storax. The results showed that Sigla storax has antibacterial activity against many bacteria at concentrations of 10.0% and against some bacteria at concentrations of 1.0%, 0.4% and 0.2%. Copyright (c) 2005 John Wiley & Sons, Ltd.
