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Öğe Antimicrobial and antioxidant activities of the various extracts of Verbascum pinetorum Boiss. O. Kuntze (Scrophulariaceae)(Verduci Publisher, 2011) Ozcan, B.; Esen, M.; Caliskan, M.; Mothana, R. A.; Cihan, A. C.; Yolcu, H.Background and Objectives: The present study was performed to evaluate the in vitro antimicrobial and antioxidant properties of various extracts of Verbascum (V.) pinetorum, a member of Scrophulariaceae family. While the antimicrobial activity of various extracts of V. pinetorum was determined with agar-well diffusion method, the antioxidant activity was examined with two complementary test systems, namely 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and beta-carotene/linoleic acid test systems. Results: The hexane extract exhibits antimicrobial activity against few microorganisms. However, dichloromethane, direct methanol and methanol/chloroform extracts are effective on a broad range of microorganisms. Among the tested bacteria Haemophilus influenzae was found to be the most sensitive bacterium. The 50% (IC50) inhibition activity of the methanolic extract of V. pinetorum on the free radical DPPH was determined as 13.04 mg/ml. In the case of the linoleic acid system, oxidation of linoleic acid was inhibited by methanolic extract of V. pinetorum, which showed 89.39% inhibition that is quite close to the value of the synthetic antioxidant reagent butylhydroxytoluene (BHT), 92.46%. Iridoid glycosides, flavonoids and saponins were determined as the major natural compounds in the methanolic extracts. The total phenolic components of V. pinetorum were found as 42.45 mg/g gallic acid equivalent. Conclusion: The results provide evidence that the extracts of V. pinetorum contained iridoid glycosides, flavonoids, saponins and phenolic compounds which may be responsible for the substantial antimicrobial and antioxidant activities.Öğe Characterization of extremely halophilic Archaea isolated from saline environment in different parts of Turkey(Maik Nauka/Interperiodica/Springer, 2006) Ozcan, B.; Cokmus, C.; Coleri, A.; Caliskan, M.Ninety-five extremely halophilic strains were isolated from six distinct saline regions of Turkey by using complex medium containing 25% NaCl. The selected regions are Tuz Golu (salt lake), Ankara; Aci Lake, Denizli; Salda Lake, Denizli; Seyfe Lake, Kyrsherhir; Tuzla Lake, Kayseri; and Bolluk Lake, Konya. The isolated strains were tested for motility, gram reaction, cell and colony morphologies, pigmentation, biochemical characteristics, and antibiotic sensitivities. According to membrane glycerol diether moieties and antibiotic susceptibilities, all isolated strains were found to belong to the domain Archaea. All isolates were examined for the presence of plasmids by agarose gel electrophoresis and it was established that most isolates contained plasmids that varied in number and whose molecular sizes ranged from 1 to 36.9 kbp. Whole-cell protein profiles from isolates were analyzed by SDS-PAGE and a similarity dendogram was constructed using the UPGMA method. Significant similarities and differences were observed among the isolates. The strains were clustered in eight groups and ten of our isolates were placed in the same group with the standard strains. The current study represents the first isolation and characterization of such a large collection of archeal strains from Turkey.Öğe Genotyping of Helicobacter pylori strains from south Turkey(Wiley-Blackwell, 2008) Uzun, S.; Aslan, A.; Temiz, M.; Hakverdi, S.; Ozcan, B.; Gulec, C.; Ozkok, E.[Abstract Not Available]Öğe In vitro antileishmanial activity of Adana propolis samples on Leishmania tropica(Springer, 2008) Duran, G.; Duran, N.; Culha, G.; Ozcan, B.; Oztas, H.; Ozer, B.Propolis (bee glue) is a natural resinous hive product, collected from various plant sources. It has attracted much attention as a useful substance applied in medicine due to its pharmacological activities. It was aimed to investigate the in vitro effects of an ethanolic extract of Adana propolis samples on the growth of Leishmania tropica. Parasite cells were treated with five concentrations (25, 50, 100, 50, 500, and 750 mu g/ml) of the propolis. The number of promastigotes in each concentration was calculated using a hemocytometer slide at 24, 48, and 72 h after being harvested. In the experiments, it was determined that the concentrations up to 100 mu g/ml of the propolis did not exhibit antileishmanial activity against the parasites cells. At these concentrations, there was no changes in terms of morphologically. In addition, there was no statistically significant difference in terms of cell count between control and these three groups (p > 0.05). However, in culture media containing the propolis samples at 250, 500, and 750-mu g/ml concentrations, statistically significant differences in cell counts were observed, as compared to the control group (p < 0.05). Our results demonstrate that ethanolic extracts of Adana propolis samples reduce the proliferation of L. tropica parasites significantly.Öğe Isolations of ?-glucosidase-producing thermophilic bacilli from hot springs of Turkey(Maik Nauka/Interperiodica/Springer, 2009) Coleri, A.; Cokmus, C.; Ozcan, B.; Akkoc, N.; Akcelik, M.From 42 different hot springs in six provinces belonging to distinct geographical regions of Turkey, 451 thermophilic bacilli were isolated and 67 isolates with a high amylase activity were selected to determine the alpha-glucosidase production capacities by using pNPG as a substrate. alpha-Glucosidase production capacities of the isolates varied within the range from 77.18 to 0.001 U/g. Eleven of our thermophilic bacilli produced alpha-glucosidase at significant levels comparable with that of the reference strains tested; thus, five strains, F84b (77.18 U/g), A333 (48.64 U/g), F84a (36.64 U/g), E134 (32.09 U/g), and A343 (10.79 U/g), were selected for further experiments. 16S rDNA sequence analysis revealed that these selected isolates all belonged to thermophilic bacilli 16S rDNA genetic group 5, four of them representing the genus Geobacillus, while strain A343 had an uncultured bacterium as the closest relative. Changes in alpha-glucosidase levels in the intracellular and extracellular fractions were determined during 48-h cultivation of A333, A343, F84a, F84b, E134, and the reference strain G. stearothermophilus ATCC 12980. According to alpha-glucosidase production type and enzyme levels in intracellular and extracellular fractions, Geobacillus spp. A333, F84a, and F84b were defined as extracellular enzyme producers, whereas the thermophilic bacterium A343 was found to be an intracellular alpha-glucosidase producer, similar to ATCC 12980 strain. Geobacillus sp. E134 differed in alpha-glucosidase production type from all tested isolates and the reference strain; it was described as a membrane-associated cell-bound enzyme producer. In this study, apart from screening a great number of new thermophilic bacilli from the hot springs of Turkey, which have not yet been thoroughly studied, five new thermostable alpha-1,4-glucosidase-producing bacilli that have biotechnological potential with alpha-glucosidases located at different cell positions were obtained.Öğe A novel application for determination of germin gene products in situ(2003) Çalişkan, M.; Ozcan, B.; Cuming, A.C.In situ nucleic acid hybridization is one of the most powerful techniques developed for localizing the expression site of a particular gene at the cell, tissue and organ levels. This method is especially useful in understanding the function of specific gene products in particular tissues and the relation between tissue function and its localization in the whole structure of an organ. In this system, labeled anti-sense RNA probes were used to hybridize with desired mRNA while labeled sense probes were used as negative control. In general, each of these labeled probes applied to successive sections rather then the same section. That might cause some uncertainty if there are any spatial differences in the expression of gene products. In the current study, in our knowledge for the first time, anti-sense and sense probes were applied to the same sample to overcome any spatial differentiation of gene expression. The technique was successfully used to localize a plant gene product by applying anti-sense probes to the one site of the section while the other site of the same section was reacted with sense probes for control hybridization. © 2003 Taylor and Francis Group, LLC.Öğe Phylogenetic Analysis and Characterization of Lipolytic Activity of Halophilic Archaeal Isolates(Maik Nauka/Interperiodica/Springer, 2012) Ozcan, B.; Ozyilmaz, G.; Cihan, A.; Cokmus, C.; Caliskan, M.Five isolates designated as B45, D83A, A206A, A85 and E49 found to possess lipolytic activities were taxonomically classified on the basis of their phylogenetic, phenotypic and chemotaxonomic characteristics. The isolates were determined to be gram-negative, catalase and oxidase positive, hydrolyzing Tween 80 and 60 but not starch, need 3.5-4 M NaCl for optimal growth and lack of anaerobic growth with arginine or DMSO. All isolates had the highest lipolytic activity at pH 8.5. Lipase and esterase activities increased with salt concentration up to 3-4.5 M NaCl, and decreased at 5 M NaCl. Esterase and lipase showed their maximal activities at 50-55 degrees C and 60-65 degrees C, respectively. The phylogenetic tree constructed by the neighbor-joining method indicated that the strain B45 and A85 were closely related to the members of genera Halovivax and Natrinema, respectively. The closest relative of the strain A206A and D83A were found to be Haloterrigena saccharevitans. The strain E49 displayed a more distant relationship to known strains.Öğe Phylogenetic analysis and characterization of lipolytic activity of halophilic archaeal isolates.(2012) Ozcan, B.; Ozyilmaz, G.; Cihan, A.; Cokmus, C.; Caliskan, M.Five isolates designated as B45, D83A, A206A, A85 and E49 and found to possess a activity were taxonomically classified on the basis of their phylogenetic, phenotypic and chemotaxonomic characteristics. The isolates were determined to be Gram-negative, catalase and oxidase positive, hydrolyzing Tween 80 and 60 but not starch, need 3.5-4 M NaCl for optimal growth and lack of anaerobic growth with arginine or DMSO. All isolates had the highest lipolytic activity at pH 8.5. Lipase and esterase activities increased with salt concentration up to 3-4.5 M NaCl, and decreased at 5 M NaCl. Esterase and lipase showed their maximal activities at 50-55 degrees C and 60-65 degrees C, respectively. The phylogenetic tree constructed by the neighbor-joining method indicated that the strain B45 and A85 were closely related to the members of genera Halovivax and Natrinema, respectively. The closest relative of the strain A206A and D83A were found to be Haloterrigena saccharevitans. The strain E49 displayed a more distant relationship to known strains.Öğe Spatial localization of germin-like oxalate oxidase genes in developing wheat shoots(2004) Çalişkan, M.; Ozcan, B.; Turan, C.; Cuming, A.C.When quiescent embryos in dry grains of ripened wheat are isolated and provided with ample water and oxygen at an appropriate temperature, they begin to grow very rapidly. The onset of the growth is signaled by nascent synthesis of germin genes which encodes a relatively rare, water-soluble homop entameric glycoprotein. Germin is resistant to pepsin digestion under conditions that lead to hydrolysis of virtually all other proteins in wheat embryos. Germin proteins have oxalate oxidase activity, an activity that degrades oxalic acid to generate hydrogen peroxide which involves in many aspects of plant development. Following 48-hour imbibition on water, wheat embryos give rise to distinguishable shoot and roots. Shoots comprise coleoptile, leaf primordium and shoot apex. In the current study, non-radioactively labeled germin riboprobes were prepared by in vitro transcription. The riboprobes were used to search and localize germin mRNAs in sections taken from throughout of shoots. The results revealed that although leaf primordium and shoot apex did not show any signals of the presence of germin mRNAs, coleoptiles as a whole tissue displayed germin gene expression on epidermal cells and vascular bundle sheath cells. Among the sections taken from different parts of shoots, the sections from middle part gave the strongest signals on coleoptile cells. © 2004 Taylor and Francis Group, LLC.
