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Öğe A new Gladiolus (Iridaceae) species from East Anatolia (Turkey): Gladiolus hamzaoglui(Magnolia Press, 2021) Tekşen, Mehtap; Duman, Hayri; Sağıroğlu, MehmetGladiolus hamzaoglui (Iridaceae) is described and illustrated as a new species from Erzincan province in Eastern Anatolia, Turkey. It resembles G. halophilus by its secund inflorescence, obovoid fruit, and winged seed, and is related to G. anatolicus based on its leaf and flower features. Also it is compared to G. illyricus because of having some leaf, flower features, and winged seed characteristics. Its distribution, habitat and ecology, etymology, conservation status and diagnostic morphological, and taxonomic features with familiar species are discussed in this paper. Additionally, pollen and seed micromorphological characteristics of G. hamzaoglui, G. halophilus, and G. anatolicus are examined and compared using LM and SEM analyses IUCN conservation status of G. hamzaoglui is suggested as Endangered (EN) category.Öğe Antimicrobial and Antioxidant Activities of Two Endemic Plants From Aksaray in Turkey(African Networks Ethnomedicines, 2013) Aşan Özüsağlam, Meltem; Önal Darılmaz, Derya; Erzengin, Mahmut; Tekşen, Mehtap; Karaman Erkul, SeherThis study was designed to examine the in vitro antimicrobial and antioxidant activities of the methanol, ethanol, water, n-hexane and dicholoromethane extracts of two Allium species (Allium scabriflorum and Allium tchihatschewii) which are endemic for the flora of Turkey. The antimicrobial efficiency of the plant was evaluated according to disc diffusion and microdilution broth methods. The antimicrobial test results showed that the extracts of A. scabriflorum and A. tchihatschewii showed varying degrees of antimicrobial activity on the tested microorganisms. The extracts were screened for their possible antioxidant activities by three complementary tests; DPPH free radical-scavenging, scavenging of hydrogen peroxide and metal chelating activity assays. All the extracts of A. scabriflorum and A. tchihatschewii exhibited lower DPPH free radical scavenging activity but higher metal chelating activity when compared to standards. The values of scavenging of hydrogen peroxide of the extracts were higher than the standards that of a-tocopherol, BHA, BHT and trolox, but close to that of ascorbic acid. In addition to the antioxidant activity of these plants, the total phenolic compounds and flavonoids were also measured in the extracts. The results presented here may suggest that the extracts of A. scabriflorum and A. tchihatschewii possess antimicrobial and antioxidant properties, and therefore, they can be used as a natural preservative ingredient in food and/or pharmaceutical industry.Öğe Antimicrobial and antioxidant activity of various solvent extracts of Salsola stenoptera wagenitz and Petrosimonia nigdeensis aellen (Chenopodiaceae) plants(Chiang Mai University, 2015) Aşan Özüsağlam, Meltem; Erzengin, Mahmut; Darılmaz, Derya Önal; Erkul, Seher Karaman; Tekşen, Mehtap; Karakoca, KübraThis study was conducted to examine the in vitro antimicrobial and antioxidant activities of various extracts (ethanol, methanol, n-hexane, dicholoromethane and water) prepared from the stem and leaf+fruit of Salsola stenoptera Wagenitz and Petrosimonia nigdeensis Aellen (Chenopodiaceae) plants. The antimicrobial activities of the plant extracts were tested according to agar well diffusion and microdilution broth methods. The extracts showed a strong antimicrobial activity and a broad antimicrobial spectrum for all tested microorganisms. Minimal bactericidal (MBC) or fungicidal (MFC) concentrations for microorganisms which were sensitive to the stem and fruit+leaf extracts of S. stenoptera and P. nigdeensis in the agar well diffusion assay were in the range of 5.63-180.00 mg/mL and 11.25-180.00 mg/mL, respectively. The extracts were also subjected to screening for their possible antioxidant activity with scavenging activity of DPPH radicals, hydrogen peroxide scavenging activity and chelating ability on ferrous ions. All tested extracts showed varying degrees of efficacy in each assay in a dose-dependent manner. In general, polar extracts exhibited stronger activities than non-polar extracts. The ethanol and n-hexane extracts of S. stenoptera and P. nigdeensis stem showed the highest scavenging abilitiy on DPPH radicals with the IC50 values of 29.84 µg/mL and 83.56 µg/mL, respectively. The total phenolic and flavonoid contents were also determined. The highest gallic acid equivalents (GAE) and quercetin equivalents (QE) values, for both plants, were 44.78 µg GAE/mg and 66.69 µg QE/mg, respectively. The results indicate that both plant species may have health benefits as sources of natural antioxidants and antimicrobial agents for use in functional foods and/or in pharmaceutical industry. © 2015, Chiang Mai University. All rights reserved.Öğe Determination of the heavy metal contents and the benefit/cost analysis of hypericum salsugineum in the vicinity of Salt Lake(Penerbit Universiti Kebangsaan Malaysia, 2021) Demir, Aynur; Baysal Furtana, Gökçen; Tekşen, Mehtap; Tıpırdamaz, RukiyeIn this study, Hypericum salsugineum, an endemic halophytic plant growing around Salt Lake, was analyzed to determine the heavy metals (chromium, lead, copper, zinc and nickel) on it and on the soil it grew. The phytoremediation potential of H. salsugineum was evaluated. In addition, the benefit cost (B/C) analysis was performed for its potential use in phytoremediation. The plant and soil samples were collected from Eskil and Cihanbeyli between May and September in 2016. A total of 300 soil and plant samples were analysed for heavy metal content. Statistical and standard benefit/cost analyses were performed for assessment. The capacity of accumulating the aforementioned heavy metals was found to be high in H. salsugineum. It was found that Ni and Pb ratio exceeded optimum values in its habitat, and H. salsugineum accumulated available Ni and Pb. When the plant was evaluated in terms of benefit/cost, B/C ratio was greater than 1 during the useful life of the study. This conclusion increases the ecological and economical values of H. Salsugineum, effecting its potential use in phytoremediation.Öğe Fritillaria arsusiana (Lilieae, Liliaceae), a new species from southern Anatolia(Magnolia Press, 2021) Yıldırım, Hasan; Tekşen, MehtapIn this study, Fritillaria arsusiana (Liliaceae) is described and illustrated as a new species from Hatay province in southern Anatolia, Turkey. It is related to F. amana and F. hermonis by habitus features and broadly campanulate flowers, but differs mainly by its bulb shape and size, smaller leaf and flower features, and flower colour. It has also been morphologically compared with F. wendelboi, F. pinardii, and F. latakiensis. The detailed description, diagnostic characters, original photographs, geographical distribution, habitat and phenology, etymology, conservation status, and identification key of the new and the related species are presented in this study.Öğe Fritillaria avromanica sp nov (Liliaeceae) from Iran and notes on F-melananthera in Turkey(Wiley-Blackwell, 2015) Advay, Mahfouz; Tekşen, Mehtap; Maroofi, HoseinFritillaria avromanica is described as a new species from Iran based on specimens collected from Hawraman. Taxonomic descriptions, illustrations, geographical distribution, habitat, ecology, and conservation status of the new species and the closely related F. assyriaca and F. melananthera are provided. In addition F. melananthera is given the rank of species, rather than being subspecies of F. assyriaca. The differences between F. melananthera and F. assyriaca are discussed with pollen and chromosomal characteristics.Öğe Fritillaria karakocanensis (Liliaceae), a new species of the F. crassifolia group from Anatolia (Turkey)(John Wiley and Sons Inc, 2023) Sonay, Veysel; Tekşen, Mehtap; Yıldırım, Hasan; Balos, Mehmet Maruf; Akan, HasanFritillaria karakocanensis (Liliaceae) is described as a new species from Turkey. It is morphologically similar to F. michailovskyi, F. reuteri and F. rhodocanakis, but differs from F. michailovskyi mainly by its longer stem, canaliculate and narrower leaves, papillose style, and the caducous tepals, from F. reuteri by its many bulblets, canaliculate leaves, longer lower leaves, fewer flowers, and longer tepals, and from F. rhodocanakis by its longer and narrower lower leaves, longer tepals, nectaries and style, and the obovoid capsule. A detailed taxonomic description, diagnostic characters, original photographs, geographical distribution, habitat and ecology, conservation assessment, and taxonomic comments regarding the new species are given.Öğe Fritillaria kordestanica (Liliaceae), a new species from western Iran(Magnolia Press, 2022) Advay, Mahfouz; Rix, Martyn; Tekşen, MehtapFritillaria Linnaeus (1753: 303; Liliaceae) comprises about 170 species of geophytic perennials (Rix 2019) occurring in most temperate regions of the Northern Hemisphere (Tomovi? et al. 2007, Hill 2014, Day et al. 2014). The largest number of taxa has been found in Turkey (46 species) and Greece (31 taxa, 26 species and five subspecies).Öğe Fritillaria shehbazii and F. selenica (Liliaceae), two new species from Iran(John Wiley and Sons Inc, 2023) Advay, Mahfouz; Tekşen, MehtapTwo new species, Fritillaria shehbazii from Western Azerbaijan province in northwest Iran and F. selenica from Kurdistan province in western Iran are described. Fritillaria shehbazii is similar to F. chlororhabdota, F. pinardii, F. zagrica, F. kordestanica, F. assyriaca and F. umitkaplanii in the F. caucasica-group in general facies, but differs mainly by the colour and size of its lowest leaves, and shape and colour of perigone segments. Fritillaria selenica is similar to F. assyriaca and F. kordestanica in general facies, but differs mainly by narrower leaves. Detailed taxonomic descriptions, diagnostic characters, original photographs, geographical distributions, habitat, phenology and ecology, etymology, conservation status and phylogenetic analysis of the new and the related species are presented.Öğe Fritillaria umitkaplanii (Liliaceae), a new species from south Anatolia(John Wiley and Sons Inc, 2023) Eker, İsmail; Tekşen, MehtapFritillaria umitkaplanii Eker & Tekşen sp. nov. (Liliaceae) is described as a new species from Turkey. It is morphologically similar to F. armena, F. pinardii and F. assyriaca, but differs from F. armena mainly by its canaliculate and broader leaves, perigone colour and shape, thin filament and anther colour; from F. pinardii by its canaliculate leaves, perigone colour, nectary characteristics, unbranched style and thin filament; and from F. assyriaca by its median leaves and bract longer than inflorescence, shape of median leaves, perigone colour, thin filament and style. Diagnostic characters, description, detailed illustration, geographical distribution, conservation assessment, identification key, observations and taxonomic comments regarding the new species are given.Öğe Fritillaria yalcinii (Liliaceae), a new species from southeastern Turkey(John Wiley and Sons Inc, 2024) Balos, Mehmet Maruf; Çeçen, Cahit; Tekşen, Mehtap; Yıldırım, Hasan; Sonay, VeyselFritillaria yalcinii (Liliaceae) is described as a new species from Diyarbakır Province, southeastern Turkey. It is superficially similar to F. carica, F. forbesii, F. minima, F. minuta, F. mughlae and F. sibthorpiana, but differs in several morphological characters, such as leaves, perigon, nectary, filament, stigma and anther. Diagnostic characteristics, a comprehensive description, photographs, geographical distribution, conservation assessment, observations and a distribution map are providedÖğe Gagea antakiensis, a new species from Southern Anatolia, Turkey and the new finding of Gagea lojaconoi (Liliaceae)(Magnolia Press, 2014) Kayıkçı, Samim; Ocak, Atila; Tekşen, Mehtap; Karaman Erkul, SeherGagea antakiensis (Liliaceae) is described and illustrated as a new species from Hatay province in South Anatolia, Turkey. The new species belongs to the section Didymobulbos, based on morphological features, and it is close to G. lojaconoi. The samples belonging to G. chrysantha species group in the Flora of Turkey were confirmed as G. lojaconoi. A taxonomic description, an illustration of the new species, geographical distribution, habitat and ecology, conservation status of the new species and its affinity to G. lojaconoi and G. chrysantha species group are given in this study. In addition, the anatomical features of G. antakiensis and G. lojaconoi are given. © 2014 Magnolia Press.Öğe Gagea vanensis, a new species and G. Chomutovae, a new record from southeastern Anatolia, Turkey (Liliaceae)(Magnolia Press, 2014) Tekşen, Mehtap; Karaman Erkul, SeherGagea vanensis sp. nov. (Liliaceae) is described and illustrated as a new species from Van province in Eastern Anatolia, Turkey. G. chomutovae is reported as a new record for the Turkish flora. Both species belong to the section Stipitatae, based on morphological features. The taxonomic relationships of G. vanensis with other taxa, such as G. ova, G. stipitata, G. absurda, G. kunawurensis, and G. chomutovae, are given. © 2015 Magnolia Press.Öğe Gladiolus alanyensis (Iridaceae), a new species from southern Turkey in the eastern Mediterranean basin(Magnolia Press, 2022) Sağıroğlu, Mehmet; Tekşen, Mehtap; Duman, Hayri; Karaman, Seher; Çakır, Ece GökçeGladiolus alanyensis is described and illustrated as a new species from Alanya, Antalya Province in South Anatolia, Turkey. In this study, the diagnostic morphological features, distribution, habitat and ecological characteristics, and conservation status of the new species are reported. It grows in calcareous areas and is morphologically close to G. anatolicus. Affinities and differences to other species such as G. triphyllus and G. humilis are also commented. Seed micromorphological characteristics of G. alanyensis, G. anatolicus and G. humilis are examined and compared using LM and SEM analyses.Öğe Heavy metal (Cr, Cu, Ni, Pb, and Zn) contents of endemic Salvia halophila plants around Lake Tuz(Toprak Gübre ve Su Kaynakları Merkez Araştırma Enstitüsü, 2022) Baysal Furtana, Gökçen; Demir, Aynur; Tekşen, Mehtap; Rashidi, Adeleh; Tıpırdamaz, RukiyeHeavy metals occur naturally in ecosystems at varying concentrations. However, heavy metal sources that have emerged in present-day mainly due to human influence, i.e. industrial activities, agricultural waste, pesticides, use of fossil fuels and traffic, have included a part of heavy metals in the ecosystem. Lake Tuz, together with the entire lake surroundings, water beds and important steppe areas, was declared Turkey’s Specially Protected Area (SPA) in 2001. Our aim in this investigation was to determine the levels of heavy metals such as Chrome (Cr), Copper (Cu), Nickel (Ni), Lead (Pb) and Zinc (Zn) in endemic Salvia halophila grown in different areas of Lake Tuz. The results of the heavy metal contents analyzed at the plant were compared with the international standard levels of heavy metals. The consequences displayed that differing extents of heavy metals are accumulated in S. halophila. The results obtained differed in accordance with the collection time and localities. When the outcomes are appraised, it is achievable to say that Pb is higher than the standard values. The findings of this investigation are the first reported results for this endemic S. halophila species that grows naturally at Lake Tuz and are important as they are newly discovered results.Öğe Oenanthe millefolia (Umbelliferae), a new species record for the Turkish and Greek flora(PENSOFT PUBL, 2016) Güner, Ebru Doğan; Tekşen, Mehtap; Bani, BarışOenanthe millefolia (Apiaceae), which is presented as a new recorded species for the Turkish flora, was discovered for the first time in Kirklareli province of Turkey. It is also reported as a new species for the Greek flora based on an unidentified specimen which was collected from the Thrace region of Greece. In this study, an expanded morphological description, the geographical distribution, the habitat properties and the ecological features of the species are exhibited with illustrative figures. Moreover, the micromorphological and anatomical characters of the fruits and the anatomical properties of the stem, petiole, leaves and the palynological features of Oe. millefolia are determined and described for the first time.Öğe Phenolic Compounds, biological and antioxidant activities of onobrychis armena Boiss. & Huet flower and root extracts(Chiang Mai University, 2015) Karakoca, Kübra; Aşan Özüsağlam, Meltem; Çakmak, Yavuz Selim; Tekşen, MehtapOnobrychis armena Boiss.&Huet (Fabaceae) is a plant species that is endemic to Turkey and grows in Aksaray. The aim of the present study is to examine antimicrobial and antioxidant activities of crude extracts of O. armena flower and root. The antimicrobial activities of the extracts were investigated by using disc diffusion and microdilution-broth methods against human and fish pathogen microorganisms. The results showed that all the extracts exhibited varying degrees of antimicrobial activity on the microorganisms tested. The antioxidant activity was determined with total antioxidant activity, free radical scavenging activity, ferric ion reducing power, and cupric ion reducing antioxidant capacity assay. In addition, the total phenolic compounds and flavonoids were measured in the extracts. The phenolic composition of the methanolic root extract was analyzed by HPLC. The HPLC analysis showed that the major component was rutin (428.80 µg/g). Cytotoxic effect of the methanolic root extract was also tested on human breast cell (MCF12A). The results showed that flower and root extracts of O. armena may be a potential source of natural antimicrobial and antioxidants and could be used as a natural source in food industry, drug discovery, clinical and food chemistry, and antimicrobial agents against human and fish pathogens. © 2015 Chiang Mai University. All rights reserved.Öğe Pollen morphology of the genus Fritillaria L. (Liliaceae) in Turkey(TÜBİTAK, 2010) Tekşen, Mehtap; Aytaç, Zeki; Pınar, Nur MünevverPollen grains of 39 taxa of the genus Fritillaria L. in Turkey were examined by light and scanning electron microscopy. Detailed pollen morphological characteristics are given for these taxa. Our investigation shows that the sculpturing of the exine provides valuable characters for separating species. In particular, sculpturing of the exine at the proximal face turned out to be taxonomically important. Six types of ornamentation were determined: reticulate, reticulate-perforate, suprareticulate, rugulate-reticulate, psilate-perforate, and perforate. On the basis of exine sculpturing, the sulcus membrane, and the apex sulcus, 5 main pollen types are recognised.Öğe Predicting the effect of climate change on the geographic distribution of the endemic Fritillaria aurea in Türkiye(Abdullah KAYA, 2024) Kenar, Nihal; Tekşen, MehtapFritillaria aurea is a rare, high altitude, endemic, and bulbous plant species in Türkiye. Although it is classified as least concern according to IUCN criteria, the species has a narrow distribution. This study utilized ensemble modeling to forecast potential future changes in suitable habitats for F. aurea by two Shared Socio-Economic Pathways (SSPs: SSP 1-2.6 and 5-8.5). These pathways were constructed using two General Circulation Models (GCMs) and covered the years 2035, 2055, and 2085. The results showed that the minimum temperature of the coldest month (bio6), mean temperature of the wettest quarter (bio8), and precipitation of the warmest quarter (bio18) have the largest influence on the potential species distribution. The ensemble model predicted that the highly suitable habitats of F. aurea would contract under all future SSP scenarios and it would lose almost all of its potential highly suitable distribution areas by the end of the century. The remained population of F. aurea could possibly harbour in only minor areas of the North Anatolian Mountains in the north and Taurus Mountains in the south. The results of the study could contribute to establishing conservation strategies and natural resource management policies for F. aurea against the potential impacts of climate change. The highly suitable habitats under pessimistic scenarios at the end of this century projected by the present study can be determined as protected areas for the species.Öğe Ranunculus aydogdui (Ranunculaceae), a new species from Turkey(Wiley, 2021) Erkul, Seher Karaman; Tekşen, Mehtap; Duman, HayriRanunculus aydogdui sp. nov. is described from Tuz Golu (Salt Lake), Aksaray, Turkey. It is compared to three similar species, R. flammula, R. pulchellus var. pulchellus and R. indivisus and it is found that R. aydogdui is distinguished from them e.g. by having tuber roots. A comprehensive description, ecology, distribution map, detailed photographs, pollen morphology and comparison of the new species with closely related species are provided. The new species is assessed as Critically Endangered (CR) following IUCN Red List Categories and Criteria.
