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Öğe 3-hydroxy fatty acids from the flowers of Hypericum lysimachioides var. lysimachioides(2004) Başhan, Mehmet; Toker, Zuhal; Keskin, Cumali; Özen, Hasan ÇetinFatty acid methyl esters in the leaves and flowers of Hypericum lysimachioides var. lysimachioides (Guttiferae) were analyzed by gas chromatography and gas chromatography-mass spectrometry. The flowers of H. lysimachioides var. lysimachioides produced unusual 3-hydroxy fatty acids [3-hydroxy- tetradecanoic acid (3-OH-C14:0) and 3-hydroxy-octadecanoic acid (3-OH-C18:0)], along with other normal fatty acids. Major components were linolenic and palmitic acids for both leaves and flowers.Öğe The antimicrobial activity of essential oils of Hypericum scabrum, Hypericum scabroides and Hypericum triquetrifolium(Wiley, 2004) Kızıl, Göksel; Toker, Zuhal; Özen, Hasan Çetin; Aytekin, ÇetinThe essential oils of Hypericum scabrum, Hypericum scabroides and Hypericum triquetrifolium were studied for the first time for their antimicrobial activity against nine organisms. All the essential oils exhibited some broad spectrum antibacterial activity, at a concentration of 80 mug/mL. The essential oils of Hypericum species showed antibacterial activity against the tested organisms and a yeast. Copyright (C) 2004 John Wiley Sons, Ltd.Öğe ANTIOXIDANT AND ANTIMICROBIAL EFFECTS OF HYPERICUM RETUSUM AUCHER PLANT EXTRACTS PREPARED IN VARIOUS SOLVENTS(Parlar Scientific Publications (P S P), 2013) Akgoz, Yasemin; Toker, ZuhalIn this study, the antioxidant and antimicrobial effects of petroleum ether, hexane, ethyl acetate and methanol extracts of Hypericum retusum Aucher are investigated. The antioxidative potential of H. retusum extracts was examined using different antioxidant tests, including the total amount of phenolic components (Folin & Ciocalteu reagent method), total amount of flavonoids, 1,1-diphenyl-2-picryl hydrazyl (DPPH)) radical scavenging, metal chelating, reducing power, and hydroxyl radical activities. At the same time, antimicrobial effects were examined in 6 types of bacteria (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Staphylococcus pyogenes ATCC 19615, Bacillus subtilis ATCC 11774, Bacillus cereus, Pseudomonas aeruginosa ATCC 27853). It has been observed from the experiments that extracts of H. retusum have high antioxidant effects and in addition, antimicrobial activity on bacteria.Öğe Astragalus diphtherites FENZL var. diphtherites ve astragalus gymnalopecias RECH. FIL’in gövde ve kök kısımlarından farklı çözücüler ile elde edilen özütlerin invitro antioksidan ve antimikrobiyal özelliklerinin belirlenmesi(Kahramanmaraş Sütçü İmam Üniversitesi, 2018) Keskin, Cumali; Özen, Hasan Çetin; Toker, Zuhal; Kızıl, Göksel; Kızıl, MuratBu çalışmanın amacı farkı polariteye sahip çözücü serilerinden geçiren Astragalus diphtherites var. diphtherites (A. diphtherites) ve Astragalus gymnalopecias (A. gymnalopecias) türlerinin gövde ve kök kısımlarının antioksidan ve antimikrobiyal özelliklerinin araştırılmasıdır. Antioksidan özellikleri belirlemek için özütlerin total fenolik, total flavonoid, DPPH, metal şelatlama, indirgeme gücü ve hidroksi radikalini söndürme aktiviteleri test edildi. En yüksek total fenolik bileşen miktarı A. diphtherites’ de gövdede metanol, kökte ise aseton özütünden elde edilirken A. gymnalopecias’ ta gövdede metanol kökte ise etil asetat özütünde tespit edildi. A. diphtherites ve A. gymnalopecias’ ta en yüksek total flavonoid miktarları ve indirgeme gücü aktiviteleri gövdede aseton kökte ise etil asetat özütlerinden elde edildi. A. diphtherites için en yüksek DPPH radikalini söndürme aktivitesi, gövdede metanol kökte ise aseton özütünde, A. gymnalopecias’ ta gövdede metanol kökte ise etil asetat özütünde tespit edildi. A. diphtherites’ te gövde kısmından elde edilen metanol ve kök kısmından elde edilen hekzan özütleri, A. gymnalopecias’ ta ise gövde ve kök kısımlarının metanol özütleri en yüksek metal şelatlama aktivitesi gösterdi. Her iki türde de gövde ve kök etil asetat özütleri en yüksek hidroksil radikali söndürme aktivitesi gösterdi. A. gymnalopecias’ın gövde aseton ve metanol özütlerinin Streptococcus pyogenes’in büyümesi üzerinde inhibisyon etkisine sahip olduğu tespit edildi.Öğe Bazı hypericum türlerinin uçucu yağ bileşenleri ve bu yağların antimikrobiyal aktiviteleri(2016) Toker, Zuhal; Özen, Hasan ÇetinBu çalışmada, Güneydoğu Anadolu bölgesinden toplanan; Hypericum hyssopifolium Chaix var. microcalysinum Boiss&Heldr, Hypericum scabroides Robson&Poulter, Hypericum scabrum L., Hypericum lysimachioides Boiss var. lysimachioides, Hypericum triquetrifolium Turra'nın uçucu yağ bileşenleri ile ve elde edilen bu yağların değişik mikroorganizmalar üzerindeki antibakteriyal ve antifungal etkileri araştırıldı. Uçucu yağlar Cockins ve Middletons aparatı ile izole edildi Uçucu yağ bileşenleri GC/MS ile aydınlatıldı. H. hyssopifolium var. microcafysinum, H. triqetrifolium ve H. lysimachioides var. lysimachioides' den karyofillen oksid, H. scabroides ve H. scabrum'dan. bisiklohept-3-en-2-on majör bileşikler olarak elde edildi Bu yağların antimikrobiyal aktiviteleri Disk Diffüzyon Yöntemi ile Staphylococcus aureus. Streptococcus pyogenes, Pseudomonas aeruginosa, Candida albicans, Escherichia coli K12, Escherichia coli PBr-322, Escherichia coli PUC9, Bacillus brevis ATCC ve Bacillus cereus üzerine çalışıldı. Yapılan çalışma, bu bitkilerin uçucu yağlarının test edilen mikroorganizmalara karşı etkili olduğunu göstermiştir.Öğe Carthamus Glaucus Bieb. üzerine fitokimyasal araştırmalar(2015) Toker, ZuhalBu çalışmada, Carthamus glaucus 'un sekonder metabolitleri incelenmiştir. Bitki kurutulup, öğütülerek EtOH ile özütlenmiştir. Evapore edilerek elde edilen bitki özütü, silika-jel kolonlarından; artan oranlarda EtOAc bulunan Hekzan-EtOAc karışımlarıyla yıkanmıştır. Kolon kromatografisi ile biribirinden ayrılan bileşikler, HPLC aracılığıyla saflaştırılmıştır. Bileşiklerin yapılarını aydınlatılmasında; Kütle, UV, İR, 13C ve XH NMR spektroskopilerinden yararlanılmıştır. Bu çalışmanın sonucunda : a-Bisabalol J3-D-Fukopiranosid 3'-izovalerinat, a-Bisabalol P-D-Fukopiranosid 3'-izobütirat, a-Bisabalol P-D-Fukopiranosid 3'-sennosinat, a-Bisabalol P-D-Fukopiranosid, 5-hidroksi 6,7-dimetoksiflavon Bileşikleri izole edilmiştir. Bu bileşiklerin ilk üçü doğadan ilk kez izole edilmiştir.Öğe Composition of essential oil of Carthamus glaucus Bieb. subsp glaucus(Asian Journal Of Chemistry, 2008) Toker, Zuhal; Keskin, CumaliThe essential oil of water distilled aerial parts of Carthamus glaucus Bieb. subsp. glaucus (Compositae) was analyzed by GC/MS. 23 Components were characterized representing 87.3% of total component in oil sample. The major components were linalool (38.5%), longifolene (6.8%) and caryophyllene oxide (6.2%).Öğe Composition of the essential oil of achillea pseudoaleppica Hub.-Mor(2003) Özen, Hasan Çetin; Toker, Zuhal; Clery, Robin A.; Owen, Neil E.; 0000-0001-6670-6469; 0000-0003-1038-9091; 0000-0001-5157-8986Water-distilled essential oil from aerial parts of Achillea pseudoaleppica, an endemic species in Turkey, was analyzed by GC and GC/MS. Seventy components were characterized representing 92.4% of the total component in oil sample. The major components were camphor (29.1%), 1,8-cineole (17.7%) and artemisia ketone (10.3%).Öğe EFFECT OF UV-C ON PRODUCTION OF HYPERICIN IN Hypericum triquetrifolium Turra GROWN UNDER IN-VITRO CONDITIONS(Parlar Scientific Publications (P S P), 2009) Namli, Suereyya; Toker, Zuhal; Isikalan, Cigdem; Oezen, Hasan CetinIn this study, the effects of UV-C radiation on the increasing of hypericin in Hypericum triquetrifolium Turra were investigated by using in vitro techniques. The mature seeds of Hypericum triquetrifolium Turra were germinated in Murashige and Skoog (MS) medium without hormone under in vitro conditions, and the shoots obtained were successfully reproduced in MS medium supplemented with 0.25 mg L-1 BA (N-6-benzylaminopurine). The UV-C radiation was applied to Hypericum triquetrifolium Turra at different periods (15, 30, 45, 60 min). Although the hypericin content increased at 15-min UV-C radiation, it decreased after 60 min of application. Depending upon different parameters of UV-C radiation, some morphological alterations were observed in shoots.Öğe Effects of UV-B radiation on total phenolic, flavonoid and hypericin contents in Hypericum retusum Aucher grown under in vitro conditions(Taylor & Francis Ltd, 2014) Namli, Sureyya; Isikalan, Cigdem; Akbas, Filiz; Toker, Zuhal; Tilkat, Emine AyazThis study was conducted to increase total phenolics, flavonoids and hypericin accumulation in in vitro cultures of Hypericum retusum Aucher to determine the appropriate time of UV radiations. Proliferation of plantlets on Murashige-Skoog medium containing 0.5 mg L-1 N-6-benzylaminopurine was achieved under in vitro conditions. Then, the plantlets were exposed to UV-B radiation for different periods (15, 30, 45 and 60 min). The highest total phenolics, flavonoids and hypericin accumulation (43.17 +/- 0.8; 35.09 +/- 0.8; 2.7 +/- 0.05 mg g(-1), respectively) was achieved at 45 minutes of exposure to UV-B radiation when compared with the contents of naturally growing plants (23.33 +/- 0.9, 18.62 +/- 0.3 and 1.6 +/- 0.01 mg g(-1), respectively) and control groups (control group was not subjected to UV-B radiation).Öğe Fatty acid and 3-hydroxy fatty acid composition of two Hypericum species from Turkey(Wiley, 2004) Özen, Hasan Çetin; Başhan, Mehmet; Keskin, Cumali; Toker, Zuhal; 0000-0001-6670-6469; 0000-0003-3758-0654; 0000-0003-1038-9091The fatty acid compositions of flowering tops of Hypericum perforatum L. and Hypericum retusum Aucher (Guttiferae) were analyzed by gas chromatography and gas chromatography-mass spectrometry. The major components were C16:0 (24.87%), C18:3 n-3 (21.94%), 3-OH-C18:0 (18.46%) and 3-OH-C14:0 (14.22%) for H. perforatum L. and 3-OH-C14:0 (28.29%), C18:0 (16.47%) and C16:0 (14.17%) for H. retusum Aucher. Besides widespread plant fatty acids, 3-hydroxy fatty acids, namely 3-hydroxytetradecanoic acid (3-OH-C14:0) and 3-hydroxyoctadecanoic acid (3-OH-C18:0) were also obtained.Öğe Mutagenicity of Hypericum lysimachioides extracts(Taylor & Francis Inc, 2009) Tolan, Veysel; Toker, Zuhal; Ozdemir, Sadin; Demirci, Oezlem; Otludil, Birol; Oezen, Hasan C.Hypericum (Hypericaceae) species are extensively used in several fields such as traditional medicine, food and crop protection. Despite its usage in many fields, the identification of the genotoxic potential of this herb is still incomplete. In this study, we evaluated genotoxic effects of the petroleum ether, hexane, ethyl acetate, and methanol extract of Hypericum lysimachioides Boiss. var. lysimachioides by Ames Salmonella/microsome test and SOS chromotest. The mutagenic activity of Hypericum lysimachioides var. lysimachioides extracts was investigated by using Salmonella typhimurium strains TA98 and TA 100 and also the SOS chromotest with Escherichia coli PQ37 strain, with or without S9 metabolic activation. In this initial report we demonstrated that all extracts of H. lysimachioides var. lysimachioides showed significant mutagenic activity on both strains of Salmonella either with or without S9 mixture. No mutagenicity was found in the SOS chromotest either with or without S9 mixture. These results indicate a significant mutagenicity of the petroleum ether, hexane, ethyl acetate and methanol extracts of Hypericum lysimachioides var. lysimachioides in vitro. It can be suggested that quercetin and flavonol or their synergistic effects may be main mutagenic agents in the photopharmaceuticals Hypericum lysimachioides var. lysimachioides extract.Öğe Variation of total hypericin, phenolic and flavonoid compounds in Hypericum triquetrifolium during its phenological cycle(Taylor & Francis Ltd, 2009) Toker, ZuhalThe genus Hypericum (Hypericaceae) contains a variety of structurally diverse natural products which possess a wide array of biological properties. The present study examined quantitative variations in total hypericin, phenols, and flavonoids in Hypericum triquetrifolium Turra. in relation to phenological development. Plant material was harvested at different phenological stages (vegetative, full flowering, and mature fruiting stages). The amounts of bioactive compounds in whole shoots were assayed. The highest total hypericin, phenolic, and flavonoid contents were observed at the full flowering stage.
