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Öğe Anti-colon cancer potential of phenolic compounds from the aerial parts of Centaurea gigantea (Asteraceae)(Springer Tokyo, 2007) Shoeb, Mohammad; Jaspars, Marcel; MacManns, Stephen M.; Celik, Sezgin; Nahar, Lutfun; Kong-Thoo-Lin, Paul; Sarker, Satyajit D.Reversed-phase HPLC analysis of the methanol extract of the aerial parts of Centaurea gigantea afforded chlorogenic acid and five flavonoids, 2-(4'-hydroxybenzoyl)-isoorientin, orientin, isoorientin, isoquercetrin and cirsiliol. The structures of the these phenolic compounds were established unequivocally by UV, MS, a series of 1D and 2D NMR analyses and by comparison of their spectroscopic data with literature data. The free radical scavenging properties of these compounds were assessed by the DPPH assay, and their toxicity towards brine shrimps, and cytotoxicity towards cancer cells were evaluated, respectively, by the brine shrimp lethality assay and the MTT assay using CaCo-2 colon cancer cell line. Among the compounds, chlorogenic acid exhibited considerable anti-colon cancer activity (IC50=79.0 mu M).Öğe Antimicrobial and Antioxidant Activities of Some Species of Centaurea Collected from Turkey(Asian Journal Of Chemistry, 2013) Uysal, Ismet; Celik, Sezgin; Saglam, Husniye; Guven, KiymetThe antimicrobial activity of the ethanol, acetone, ethyl acetate and chloroform extracts from Centaurea persica Boiss., C. polyclada DC. and C. consanguinea DC. (Asteraceae) were investigated by agar-well diffusion assay. All of the extracts exhibited an antimicrobial effect against most of the bacteria and all of the yeasts tested. The plant extracts were also screened for radical scavenging potential using a 1,1-diphenyl-2-picryl-hydrazyl (DPPH) in vitro model system for antioxidant activity. Ethyl acetate extracts showed the most significant inhibitory activity. Therefore, the minimal inhibitory concentration (MIC) of only ethyl acetate extracts of the samples was determined and C. consanguinea showed the highest antimicrobial effect. However, the ethanol extract of C. polyclada at 0.5 mg/ml, concentration displayed the highest antioxidant activity. This activity was followed by ethanol extracts of. C. persica, ethyl acetate extracts of C. polclada, C. persica and C. consanguinea respectively.Öğe Bioactivity of two Turkish endemic Centaurea species, and their major constituents(Sociedade Brasileira de Farmacognosia, 2007) Shoeb, Mohammad; MacManus, Stephen M.; Jaspars, Marcel; Kong-Thoo-Lin, Paul; Nahar, Lutfun; Celik, Sezgin; Sarker, Satyajit D.The antioxidant activity, general toxicity and cytotoxicity of the methanol extracts of Centaurea urvillei subs, armata and C. mucronifera have been assessed, respectively, by the DPPH assay, the brine shrimp lethality and the MTT cytotoxicity assays. The reversed-phase HPLC analysis of the methanol extracts afforded two bioactive dibenzylbutyrolactone-type lignans, matairesinoside (1) and arctiin (2). The structures of these lignans were elucidated by comprehensive spectroscopic analyses as well as by the direct comparison of experimental data with respective literature data.Öğe Ecotourism Potential of Gallipoli Peninsula Historical National Park(Coastal Education & Research Foundation, 2010) Kelkit, Abdullah; Celik, Sezgin; Esbah, HayriyeEcotourism in protected areas is growing rapidly all around the world Although the benefits of ecotourism are well described, It is not a panacea for solving the complex human needs and resource-capacity paradox in protected areas, unless it is well planned and managed The notion of ecotounsin in legally protected areas is relatively new in Turkey, and therefore none of Turkey's 39 national parks has an ecotourism master plan The purpose of this study is to analyze the ecotourism potential and to generate initial recommendations for establishing an ecotourism framework for Gallipoli Peninsula Historical National Park (GPHNP) in Canakkale, Turkey Three basic research steps are followed analysis, evaluation, and synthesis Natural, cultural, and historical features of GPHNP are presented, and a set of recommendations are provided with respect to ecotourism in the study area Results indicate that the national park has substantial potential for ecotourism activities such as bird-watching, photo safari, wildlife watching, sportfishing, bicycling, scuba diving, farming tourism, flora tourism, trekking, and horseback riding through nature, and this potential is not sufficiently utilized in the current context The recommendations include that the national park's war history, biological diversity, coastal morphology, and climate should be promoted holistically, and awareness of them should he raised The topography and other landscape attributes of the park must be protected and sustainedÖğe ETHNOECOLOGY OF POISONOUS PLANTS OF TURKEY AND NORTHERN CYPRUS(Pakistan Botanical Soc, 2008) Ozturk, Munir; Uysal, Ismet; Guecel, Salih; Mert, Tuba; Akcicek, Eren; Celik, SezginInterest in plants is increasing and much work is being carried out these days on their multipurpose uses. A great impetus has been given to this during the last 3 decades. Several publications have been made by different investigators. Large number of naturally growing plants are collected and sold at the markets. Nearly 500 plants are used for primary health care in Turkey and a 23 in Cyprus. However, not much is known about the poisonous plants. Some of these are toxic and others cause reaction. Plant poisoning lies around 6%, rurals suffer more from the consumption of naturally growing plants as compared to urban dwellers. One has to be very cautious before using these plants as the plants used for the purpose of treatment of diseases as a whole or parts thereof or consumed by the public directly could prove dangerous for the health. This paper describes ethnoecological aspects of the widely distributed major poisonous plants in Turkey and Northern Cyprus which can prove fatal if used unknowingly. Major applications and active constituents of plant taxa are outlined.Öğe Morphology, anatomy, ecology and palynology of two Centaurea species from Turkey(Bangladesh Botanical Society, 2008) Celik, Sezgin; Uysal, Ismet; Menemen, YusufCentaurea L. sect. Ptosimopappa, a local endemic group in the Mediterranean and South East Anatolia, is represented by only two species, namely C. ptosimopappa Hayek and C. ptosimopappoides Wagenitz in Turkey. Both these species show a very restricted distribution as serpentine habitat indicators and are recorded as vulnerable. Present study was carried out to enlighten the morphological, anatomical and ecological features of these two species in detail. The structure of achene, indumentum and pollen grains were investigated by using Scanning Electron Microscope (SEM). The capitulum, involucre and leaf structure of these two species are rather similar, but their achenes and pollen grains differ from each other. In C. ptosimopappa pollen spinules are densely distributed but in C. ptosimopappoides they are sparsely distributed. The achenes arc obovate in C. ptosimopappa and rectangular in C. ptosimopappoides. C. ptosimopappa is a scrub species but C. ptosimopappoides is a subscrub species. A negative relation in terms of the proportion of sand to silt content of the soil and positive relation between the percentage of CaCO3 and pH was observed for C. ptosimopappa (p < 0.05). A negative relation in terms of the proportion of sand to silt content of the soil was observed in C. ptosimopappoides (p < 0.01).Öğe Plant species microendemism, rarity and conservation of pseudo - alpine zone of Kazdagi (Mt. Ida) national park - Turkey(Elsevier Science Bv, 2011) Ozturk, Munir; Uysal, Ismet; Karabacak, Ersin; Celik, SezginKazdag (Mt. Ida) forms a natural border between the Provinces of Canakkale and Balikesir in the north-western part of Turkey. It was declared as National Park in 1993 because of its rich plant cover, a restricted zone of Abies nordmanniana ssp. equi-trojani forest, natural beauty and mythology. The pseudo-alpine zone consists of 189 specific and infraspecific taxa of vascular plants. A total of 55 endemic taxa (29.10%) were recorded from this area. Out of these 22 (40%) taxa are restricted only to this area, and 5 taxa are non-endemic but rare in Turkey. In this paper, habitat characteristics, conservation strategies and management of these taxa are given. Our investigations revealed that, out of 55 taxa, 12 are critically endangered (CR), 10 endangered (EN), 11 vulnerable (VU), 9 not threatened (NT) and 18 with lower risk (LC). Although Hieracium idae, Dianthus arpadianus var. trojanus, Minuartia garckeana and Paronychia sintenisii are recorded as data deficient (DD) category in IUCN criteria, these taxa are transferred to CR category. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of The 2nd International Geography Symposium-Mediterranean EnvironmentÖğe Pollen studies on some Turkish endemic species of Centaurea L. (Asteraceae)(EuroJournals, Inc., 2007) Celik, Sezgin; Uysal, Ismet; Menemen, YusufPollen grains of nine endemic Turkish Centaurea L. were studied by using scanning electron microscope (SEM). The species are: C. spicata Boiss. (Sect: Cynaroides), C. tomentella Hand.-Mazz. (Sect: Cynaroides), C. screlolepis Boiss. (Sect: Cynaroides), C. amonicola Hub.-Mor. (Sect: Cynaroides), C. kurdica Reichardt (Sect: Cynaroides), C. haussknetchii Boiss. (Sect: Cynaroides), C. odyssei Wagenitz (Sect: Pteracantha), C. polyclada DC. (Sect: Acrolophus) and C. consanguinea DC. (Sect: Acrolophus)). The polen grains are tricolporate, prolate to prolate spheroidal, with sparsely or densely distributed spinules ranging from 0.50 to 1.73 ?m height and with irregular pores. P/E ratio in the grains ranges between 1.05 and 1.73. It was determined that the pollen features could be used in separation of some species studied. © EuroJournals Publishing, Inc. 2007.Öğe Screening of Turkish endemic Teucrium montbretii subsp pamphylicum extracts for antioxidant and antibacterial activities(Elsevier Sci Ltd, 2007) Ozkan, Gulcan; Kuleasan, Hakan; Celik, Sezgin; Gokturk, R. Suleyman; Unal, OrhanThe antioxidant and antimicrobial activities of Teucrium montbretii Bentham subsp. pamphylicum P.H. Davis (Lamiaceae) methanolic extracts were investigated. Total contents of phenolic compounds, flavonols and flavanols were determined by Folin-Ciocalteu colorimetric, Neu's reagent solution and vanillin colorimetric methods, respectively. Total phenolics were 99.4 mg gallic acid equivalents (GAE)/g. Total flavanols. and flavonols were 43.8 mg catechin equivalents (CE)/g and 0.5 mg rutin equivalents (RE)/g, respectively. At 100 ppm, the free radical scavenging activity was 58.6%. Antioxidant activity measured by the phosphomolybdenum method was 191.5 mg/g. Antibacterial activity was assessed (1%, 2.5%, 5%, 7.5% and 10% w/v) by the agar diffusion method against 10 species. Concentrations of 1% and 2.5% were not effective against any of the bacteria. The most resistant bacterium was Salmonella typhi while Listeria monocytogenes showed the highest sensitivity. (c) 2006 Elsevier Ltd. All rights reserved.Öğe Soil chemical differences between pasture types in Southern Marmara, Turkey(Asian Journal Of Chemistry, 2008) Hakyemez, B. Hakan; Parlak, Altingul O.; Celik, Sezgin; Gokkus, AhmetIn this study, the effects of soils on poor yield and condition of pastures in Southern Marmara, Turkey were determined. For this reason, total of 60 soil samples, in Spring 2006, were collected from 5 types of pastures in Canakkale, Balikesir and Bursa provinces, all located in the Southern Marmara region. Pasture types investigated were mountain, shrubland, coastal, lowland and forest gap type pastures. All of the collected soil samples were being evaluated for soil electrical conductivity (EC), pH, CaCO3, P, K, Ca. Mg, Na, Fe, Mn, Zn, Cu and organic matter. The EC (P = 0.000), CaCO3 (P = 0.009), organic matter (P = 0.000), P (P = 0.003), K (P = 0.027), Fe (P = 0.025) and Cu (P = 0.047) levels of soils were significantly different between pastures. Highest levels of EC (1.67 +/- 0.82 dS m(-1)) and of CaCO3 (5.81 +/- 1.02 %), were found in the soil samples obtained from coastal region and shrubland type pastures, respectively. However, the highest levels of both organic matter (4.94 +/- 0.50 %) and P (49.0 +/- 3.4 ppm) were found in both forest gap and lowland type pastures. Cu level was the highest in coastal type pastures among all 5 types of pastures analyzed. Among the provincial pastures, pH (P = 0.009), organic matter (P = 0.007), P (P = 0.002). Ca (P = 0.019), Mg (P = 0.020), Fe (P = 0.000), Zn (P = 0.013) and Cu (P = 0.003) levels of soils were significant. The highest levels of pH (7.40 +/- 0.11), of CaCO3 (4.87 +/- 0.61 %), of Ca (3049 +/- 275 ppm) and of Mg (656.7 +/- 60.9 ppm) level were found in pastures of Canakkale province while the highest levels of organic matter (%4.01 +/- 0.40), of Fe (22.8 +/- 3.0 ppm), of Zn (1.21 +/- 0.10) and of Cu (0.92 +/- 0.08 ppm) were found in pastures of Bursa province. Overall results of this study indicated that pastures of Southern Marmara region do not have very significant problem in their soil chemical compositions., Therefore, in order to improve these pastures, prescribed grazing management or weed/vegetation management practices should be applied.Öğe Studies on the germination of three endangered Centurea species(Pakistan Botanical Soc, 2006) Celik, SezginCenturea spicata, C. fenzlii and C. kurdica are widely used as ornamental plants in the Mediterranean and East Anatolian regions of Turkey. C. spicata occupies serpentine habitats in the macchia formations whereas C. fenzlii and C. kurdica cover basaltic and dolomitic habitats among the tragacanthic steppe. However, these species are facing a threat of extinction due to overexploitation. As such, an attempt was made to investigate the possibilities for then propagation. For this purpose, the seeds were placed for germination at Optimum temperature (25 1(C-0) in different concentrations of KNO3, HCl and NaCl. Two different photoperiods (8 hours light-16 hours darkness-I and 16 hours light-8 hours darkness-II) were used to mimic the natural conditions. Studies on the germination of three species undertaken to evaluate the possibilities to cultivate the native populations at a large scale showed that C. spicata did not germinate at 3 % NaCl, 2-3 % HCl and 3 % KNO3 under,both photoperiods, but germination rate was highest in 11,1 % KNO3 whereas germination percentage was higher in 0.5% KNO3 and control group under photoperiod 1. Under photoperiod 11 germination rate was highest in 1% NaCl and control. In the case of C. fenzlii the germination failed in 3 % NaCl, 2-3% HCl and 3 %KNO3 under both photoperiods but under photoperiod I the germination rate was highest in control and 0.5% KNO3, whereas the highest percentage germination was examined in control and 1% KNO3. Under photoperiod 11 germination rate was highest in 1-2 %NaCI and control, and germination percentage was highest in control and 0.5% KNO3. In C. kurdiect under photoperiod I germination rate was highest in control and 1% KNO3 but percentage germination was highest in control and 0.5 % KNO3, whereas under photoperiod II rate of germination was highest in control and I % KNO3 and germination percentage in control and 0.5% KNO3.Öğe Two salonitenolide derivatives from the aerial parts of Centaurea gigantea inhibit the growth of colorectal cancer cells in vitro(Natural Products Inc, 2007) Shoeb, Mohammad; Celik, Sezgin; Nahar, Lutfun; MacManus, Stephen M.; Kong-Thu-lin, Paul; Jaspars, Marcel; Sarker, Satyajit D.The cytotoxic activity of two salonitenolide derivatives, 8-O-(3-hydroxy-2-methylpropanoyl)-salonitenolide (or arctiopicrin, 1) and 8-O-(4-hydroxy-3-methylbutanoyl)-salonitenolide,(2), isolated and identified from the methanol extract of the aerial parts of Centaurea gigantea, was assessed by the MTT cytotoxicity assay using the colon cancer cell line, CaCo-2. The IC50 values for 1 and 2 were found to be 8.5 and 26.4 mu M, respectively.Öğe Volatile constituents of aerial parts of three endemic Centaurea species from Turkey(Taylor & Francis Ltd, 2008) Formisano, Carmen; Rigano, Daniela; Senatore, Felice; Celik, Sezgin; Bruno, Maurizio; Rosselli, SergioThe volatile constituents of the aerial parts of Centaurea amanicola Hub.-Mor., Centaurea consanguinea DC. and Centaurea ptosimopappa Hayek were extracted by hydrodistillation and analysed by GC and GC-MS. Altogether 94 components were identified. Sesquiterpenoids, fatty acids and carbonylic compounds were the most abundant components in the oils. Hexadecanoic acid and (Z,Z )-9,12-octadecadienoic acid were the main fatty acids in all the examined samples, that showed different patterns of composition. The study on the biological activity of the oils showed an action mainly against the Gram-positive pathogens.
