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Öğe Antioxidant potentials and anticholinesterase activities of methanolic and aqueous extracts of three endemic Centaurea L. species(Pergamon-Elsevier Science Ltd, 2013) Aktumsek, Abdurrahman; Zengin, Gokhan; Guler, Gokalp Ozmen; Cakmak, Yavuz Selim; Duran, AhmetThe methanol and aqueous extracts of three endemic Centaurea species (C. polypodiifolia var. pseudobehen, C pyrrhoblephara and C antalyense) were investigated for their antioxidant and cholinesterase inhibitory activities. The antioxidant activities of these extracts were evaluated by in vitro models including, phosphomolybdenum assay, free radical scavenging assays (DPPH and ABTS), beta-carotene/linoleic acid test system, metal chelating assay, FRAP assay, ferric and cupric reducing power. Cholinesterase inhibitory activities were examined using Ellman's calorimetric method. Total phenol, flavonoid, and saponin contents were also measured. Among the six Centaurea extracts evaluated, the highest antioxidant abilities were obtained from C polypodiifolia var. pseudobehen. Methanolic extracts from C polypodiifolia var. pseudobehen and C antalyense had a noticeable inhibition towards AChE and BChE. These findings suggest that Centaurea species could be an anticholinesterase agent and antioxidant resource in some industries, such as food, pharmacology, and cosmetics. (C) 2013 Elsevier Ltd. All rights reserved.Öğe Assessment of the antioxidant potential and fatty acid composition of four Centaurea L. taxa from Turkey(Elsevier Sci Ltd, 2013) Aktumsek, Abdurrahman; Zengin, Gokhan; Guler, Gokalp Ozmen; Cakmak, Yavuz Selim; Duran, AhmetThis paper focused on the assessment of antioxidant property and fatty acid composition of four Centaurea species. The antioxidant activity of its methanol extract was evaluated by several in vitro experiments including phosphomolybedum assay, DPPH assay, beta-carotene/linoleic acid, ferric and cupric reducing power. Total phenolic and flavonoid contents were also evaluated. The methanol extract of Centaurea pulcherrima var. pulcherrima showed the superior free radical scavenging activity, linoleic acid inhibition capacity, reducing power and also had the highest total phenolic content. A significant relationship between antioxidant capacity and total phenolic components was found. The oils of Centaurea taxa were also analysed for fatty acid concentration by gas chromatography. The principal fatty acids in the species were palmitic acid (23.38-30.49%) and linoleic acid (20.19-29.93%). These findings suggest that the Centaurea species could be used as a potential source of new natural antioxidants and unsaturated fatty acids in food industry, cosmetics and pharmaceutical preparations. (c) 2013 Elsevier Ltd. All rights reserved.Öğe Contribution to the cytotaxonomic knowledge of 10 species of Klasea Cass. (Asteraceae) from Turkey(Firenze Univ Press, 2015) Martin, Esra; Dogan, Bekir; Duran, Ahmet; Coskun, Fatih; Altinordu, FahimIn the present study, karyotype analyses of 10 taxa belongs to the genus Klasea Cass. (Asteraceae) were conducted. Somatic chromosome numbers are not a distinctive character of classification of Klasea taxa. All of the taxa were counted as 2n = 30 chromosomes, except for Klasea radiata subsp. biebersteiniana (2n = 60). Although all the taxa have a chromosome number of 2n = 30, they could be differentiated by their karyotype formula and quantitative parameters of the karyotype. Karyotype analysis was performed by means of an Image Analysis System and karyotype asymmetry indices were measured. According to these parameters, karyological relationships among studied taxa were inferred.Öğe Jurinea kemahensis (Asteraceae), a new species from East Anatolia, Turkey(Finnish Zoological Botanical Publishing Board, 2014) Dogan, Bekir; Kandemir, Ali; Osma, Etem; Duran, AhmetA new species Jurinea kemahensis B. Dogan, Kandemir & A. Duran (Asteraceae) is described from East Anatolia, Turkey. It grows in calcareous crevices in the Kemah district (Erzincan province) in the East Anatolia. It is morphologically fairly similar to J. tortumensis, and its diagnostic morphological characters are discussed. The ecology and distribution of J. kemahensis are also presented. The pollen characteristics and achene surface of J. kemahensis and J. tortumensis were examined by SEM.Öğe Klasea serratuloides subsp karamanica subsp nov (Asteraceae), from the central and south Anatolia transition zone, Turkey(Wiley, 2014) Dogan, Bekir; Duran, Ahmet; Coskun, FatihA new subspecies, Klasea serratuloides (DC.) Greuter & Wagenitz subsp. karamanica B. Dogan & A. Duran (Asteraceae), is described and illustrated from Anatolia, Turkey. The subspecies grows on stony places in the Ayranci and Ermenek district (C4 Karaman Province), Eregli district (C5 Konya province) and Ulukisla (C5 Nigde province) in the central and south Anatolia transition zone. It is morphologically similar to K. serratuloides subsp. serratuloides. Diagnostic morphological characters from closely similar taxa are discussed and arranged in a key. Ecology and conservation status of the subspecies is also presented. In addition, the geographical distribution of the new subspecies and other related species is mapped. The pollen morphology and achene surface of K. serratuloides subsp. karamanica and K. serratuloides subsp. serratuloides were examined by SEM.Öğe New Karyotypes in Some Species of Asteraceae from Turkey(Univ Tokyo Cytologia, 2015) Martin, Esra; Cetin, Ozlem; Duran, Ahmet; Dogan, Bekir; Tras, ZeynepIn this study, chromosome numbers and morphologies are presented for four species growing naturally in Turkey. These species are Inula peacockiana (Aitch. & Hemsl.) Korovin, Cousinia boissieri Buhse, Scorzonera renzii Rech. f., Lactuca intricata Boiss. Chromosome number of studied species are Inula peacockiana 2n=20, Cousinia boissieri 2n=26, Scorzonera renzii 2n=14 and Lactuca intricata 2n=18. Also, karyotype analyses were made using the Bs200Pro Image Analysis Software. In addition, the karyotype asymmetry of each taxa was evaluated by different methods; TF%, AsK%, Rec and Syi, A(1), A(2), A, AT and Stebbins classification. The correlation between the karyotype asymmetries of the different taxa was calculated.Öğe New Karyotypes in Some Species of Asteraceae from Turkey(Univ Tokyo Cytologia, 2015) Martin, Esra; Cetin, Ozlem; Duran, Ahmet; Dogan, Bekir; Tras, ZeynepIn this study, chromosome numbers and morphologies are presented for four species growing naturally in Turkey. These species are Inula peacockiana (Aitch. & Hemsl.) Korovin, Cousinia boissieri Buhse, Scorzonera renzii Rech. f., Lactuca intricata Boiss. Chromosome number of studied species are Inula peacockiana 2n=20, Cousinia boissieri 2n=26, Scorzonera renzii 2n=14 and Lactuca intricata 2n=18. Also, karyotype analyses were made using the Bs200Pro Image Analysis Software. In addition, the karyotype asymmetry of each taxa was evaluated by different methods; TF%, AsK%, Rec and Syi, A(1), A(2), A, AT and Stebbins classification. The correlation between the karyotype asymmetries of the different taxa was calculated.Öğe Psephellus vanensis (Asteraceae), a new species from east Turkey(Pensoft Publishers, 2015) Dogan, Bekir; Behcet, Lutfi; Duran, Ahmet; Avlamaz, DavutA new species, Psephellus vanensis A.Duran, Behcet & B.Dogan (Asteraceae) from Anatolia, Turkey, is described and illustrated. The species grows on the serpentine stony field of the village of caldiran in the district of Baskale (Van province) in eastern Anatolia. It is morphologically similar to Psephellus pyrrhoblepharus (Boiss.) Wagenitz. Diagnostic characters are discussed, and a key to the most similar species is provided. Ecology, conservation status and notes on biogeography of the species are also presented. In addition, the geographical distribution of the new species and other related species in Turkey is mapped.Öğe Seed morphology of some Genista taxa growing in Turkey(2013) Dinç, Muhittin; Kaya, Ayla; Duran, AhmetBirçok Angiosperm familyasında tohum makro ve mikromorfolojisi taksonomik öneme sahiptir. Bu çalışmada, Türkiye’de yetişen bazı Genista tohumlarının stero ve taramalı elekton mikroskobu (SEM) kullanılarak morfolojileri çalışılmıştır. Sonuçlar göstermektedir ki, tohum boyutları ve renkleri cinsin seksiyonlarının sınıflandırılmasında taksonomik değere sahiptir. Bununla birlikte tohum yüzeyi taksonlar arasında az ya da çok farklıdır ve Türkiye’de cinsin seksiyon sınıflandırmasında anlamlı değildir.Öğe Study of phylogenetic relationship of Turkish species of Klasea (Asteraceae) based on ISSR amplification(Pensoft Publishers, 2015) Dogan, Bekir; Duran, Ahmet; Seker, Meryem; Cetin, Ozlem; Martin, EsraKlasea is a taxonomically complex genus in which there are many problems, mostly with Klasea kotschyi and K. hakkiarica. It is challenging to differentiate the genera based on morphological characters alone. Revision studies performed on the basis of molecular data obtained from studies conducted in recent years have made the phylogenetic relationships and systematic positions of the taxa more apparent and reliable. In this study, Klasea, Serratula, Jurinea and Centaurea species native to Turkey, were collected from different localities of Anatolia and DNA was isolated from the collected samples. The data were analyzed ordination analyses including UPGMA and PCA using NTSYSpc 2.1. The infrageneric and intergeneric phylogenetic relationships between Klasea and other related genera were also characterized. The Klasea species were grouped into three clusters. It was determined that taxa Klasea kotschyi and K. hakkiarica are separate but closely related. Moreover, it was observed that the Klasea lasiocephala a separate group within the genera. Clearly the genera Klasea, Serratula, Jurinea and Centaurea are phylogenetically differentiated on the dendogram.
