Kuddisi Ertuğrul

Volatile constituents of two endemic Centaurea species from Turkey: C. pseudoscabiosa subsp. pseudoscabiosa and C. hadimensis

The essential oils obtained from two endemic Centaurea species (Compositae) from Turkey, C. pseudoscabiosa subsp. pseudoscabiosa Boiss. et Buhse (Sect. Acrocentron) and C. hadimensis Wagenitz, K. Ertugrul et H. Dural (Sect. Psephelloideae), have been studied. Germacrene D was the major component (36.0 and 44.3%, respectively), followed by β-caryophyllene, bicyclogermacrene and β-sesquiphellandrene.

ESSENTIAL OIL COMPOSITION OF TWO ENDEMIC CENTAUREA SPECIES FROM TURKEY CENTAUREA MUCRONIFERA AND CENTAUREA CHRYSANTHA COLLECTED IN THE SAME HABITAT

The essential oils of two endemic Centaurea species from Turkey, C. mucronifera and C. chrysantha, collected in the same habitat, have been studied. The main compounds of the former were germacrene D (29.3%), β-eudesmol (17.4%) and β-caryophyllene (7.3%), while in the latter germacrene D (27.4%), caryophyllene oxide (9.5%) and bicyclogermacrene (5.4%) were detected among its major constituents. The two species produced many similar compounds in their essential oils that could be justified by the similar ecological conditions of their habitat, but also many differences were found that could confirm their taxonomic separation.

Flavonoid glycosides from Centaurea pseudoscabiosa subsp. pseudoscabiosa from Turkey

Three flavonoid glycosides were isolated and characterized, together with a further 13 substances belonging to various classes of compounds, in particular two phenolic acids, a coumarin, a sugar and nine flavonoids from the flowered aerial parts of Centaurea pseudoscabiosa subsp. pseudoscabiosa Boiss. et Buhse (Asteraceae). Some considerations about their evolutionary meaning are provided.

A new species of Centaurea sect. Psephelloideae (Compositae) from SW Turkey

Abstract Wagenitz, G., Ertugrul, K. & Dural, H.: A new species of Centaurea sect. Psephelloideae (Compositae) from SW Turkey. — Willdenowia 28: 157–161. 1998. — ISSN 0511-9618. Centaurea hadimensis from the Central Taurus is described as a species new to science and illustrated. It belongs to C. sect. Psephelloideae and is allied to C. pyrrhoblephara, C. taochia and C. holtzii, which are likewise endemic to a restricted area within Turkey.

A multivariate statistical approach to Centaurea classification using essential oil composition data of some species from Turkey

The composition of the essential oils of ten Centaurea species from Turkey, Centaurea aladaghensis, C. antiochia var. prealta, C. antitauri, C. babylonica, C. balsamita, C. cheirolepidoides, C. deflexa, C. iconiensis, C. lanigera, C. ptosimopappoides have been studied. Multivariate statistical analyses (Principal Component Analysis, Multidimensional Scaling, Hierarchical Cluster Analysis) applied to GC-MS data, seem to be very useful to investigate and establish the natural taxonomic delimitation of this very difficult genus. The groupings resulted independent from the ecological similarities (i.e. plants that live in the same habitats or share similar morphological characteristics), so it seems that the environment has no influence on the biosynthesis of the volatiles of these plants.

Karyological studies of the genus Onobrychis Mill. and the related genera Hedysarum L. and Sartoria Boiss. & Heldr. (Fabaceae, Hedysareae) from Turkey

Nine chromosome counts in several genera of the tribe Hedysareae from Turkey, six species of Onobrychis, two species of Hedysarum and one species of Sartoria, were reported and all karyotypes were prepared. Six of them are new. One of the other three reports is a confirmation of polyploidy, another report is a confirmation of chromosome count and the last report is a confirmation of both chromosome count and karyotype morphology. Except for karyotype of O. altissima, all karyotypes were presented in this study first.

Anti-proliferative activity of aguerin B and a new rare nor-guaianolide lactone isolated from the aerial parts of Centaurea deflexa

The phytochemical investigation of the aerial parts of Centaurea deflexa led to the identification of 21 compounds, among which three phenolic acids, one sterol, ten flavonoids, one phenylpropanoid derivative, two lignans and four sesquiterpene lactones. One of the latter compounds was a new, rare active principle (1) having an uncommon 15-nor-guaianolide skeleton. The biological investigation was carried out through a bio-guided assay fractionation of C. deflexa extracts and highlighted an anti-proliferative activity of two sesquiterpene lactones, aguerin B and the newly identified 15-nor-guaianolide (1) against human pancreatic and colonic cancer cells. Of the two compounds, only aguerin B showed to induce apoptotic cell death, confirming the role as pro-apoptotic moiety of the α-methylene-γ-lactone ring present in aguerin B but not in 1.

The systematic position of Centaurea ensiformis and Centaurea isaurica from Turkey and the evolution of some characters in Centaurea

The systematic affinities of Centaurea ensiformis and Centaurea isaurica, two rare Turkish endemics, were difficult to establish on the basis of morphological characters. Their systematic position was recently unraveled by DNA sequence analyses, and they appear to be related to sect. Cheirolepis. We have carried out a detailed study of the main morphological characters that are used for the sectional classification of Centaurea, the appendages of the bracts and the achenes, in a wide sample of sect. Cheirolepis. The main conclusion is that the extremes of diversity in the shape of the appendages can be connected by intermediate forms, and a hypothesis of the evolution of the appendages is offered. This hypothesis, together with some cases of parallel evolution, would explain why there are so many examples of misclassifications based on this character alone. Regarding achenes, our conclusion is that they are important for the species level, but not useful for sectional classification of this group. Finally...

A new genus segregated from Thermopsis (Fabaceae: Papilionoideae): Vuralia

A relict endemic species originating from Turkey, Thermopsis turcica, was excluded from Thermopsis in consideration of morphologic studies based on its flowers and fruits as well as micromorphological features that were obtained by scanning electron microscopy (SEM) and data from supporting molecular analyses internal transcribed spacer (ITS). Additionally, phylogenetic analyses (maximum parsimony and neighbour-joining) were conducted using PAUP 4.0 software. These analyses supported a new taxonomical position for the Turkish species. SEM and morphological studies indicated that the species has unique features that have not been observed in other Thermopsideae species. The unique features and characteristics are comprehensively illustrated here. For confirmation of our purpose, the chromosome number and karyotype of V. turcica were determined via the KAMERAM software program. As a result, all detailed examinations and comparisons of Vuralia and related genera suggest that Vuralia is a new monotypic genus within Thermopsideae, and a new genus and combination nova were established for this Turkish species.

Karyological studies of some species of the genus Vicia L. (Leguminosae) in Turkey

In this study, 11 Vicia taxa naturally distributed in Turkey were karyologically studied. Chromosome numbers, karyotypes and idiograms of five taxa that belong to section Cracca of the genus Vicia (Vicia cracca subsp. gerardii, V. cracca subsp. atroviolacea, V. cracca subsp. stenophylla, V. canescens subsp. canescens, V. palaestina) and six taxa that belong to section Vicia (Vicia michauxii var. stenophylla, V. pannonica var. pannonica, V. hybrida, Vicia sativa subsp. nigra var. nigra, Vicia sativa subsp. nigra var. segetalis, Vicia sativa subsp. incisa var. cordata) were done. The chromosome numbers of these taxa were found as 2n = 10, 12, 14, 24. The chromosome numbers and karyotype analysis of five of these were reported for the first time and chromosome morphology of two taxa was identified for the first time. Also chromosome numbers of six taxa were verified. These results will contribute to the taxonomy of the genus Vicia which has a high diversity in Turkey.