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Dive into the research topics where Betül Demirci is active.

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Featured researches published by Betül Demirci.


Journal of Agricultural and Food Chemistry | 2009

Bioactivity-Guided Fractionation and GC/MS Fingerprinting of Angelica sinensis and Angelica archangelica Root Components for Antifungal and Mosquito Deterrent Activity

David E. Wedge; J. A. Klun; Nurhayat Tabanca; Betül Demirci; T. Özek; K. H.C. Baser; Zhijun Liu; Sui Zhang; Charles L. Cantrell; Jian Zhang

Bioassay-guided fractionation of the chloroform extract from the roots of Angelica sinensis led to isolation and characterization of (Z)-ligustilide using direct-bioautography with Colletotrichum species. The structure of (Z)-ligustilide was confirmed by (1)H and (13)C NMR spectroscopy and GC/MS. (Z)-Ligustilide deterred the biting of two mosquito species more effectively than DEET. Three different A. sinensis accessions and one Angelica archangelica root oil were evauated by GC and GC/MS, and the dominant component in A. sinensis was 61-69% (Z)-ligustilide. Two other prominent compounds in A. sinensis oils were 5.7-9.8% (E)-3-butylidene phthalide and 1.5-2.3% (Z)-3-butylidene phthalide. The main constituents that comprised A. archangelica oil were monoterpene hydrocarbons such as 24.5% alpha-pinene, 13.8% delta-3-carene, 10.1% beta-phellandrene, 8.8% p-cymene, 8.4% limonene, and 6.3% sabinene. Phthalides and monoterpene hydrocarbons were determined to be good systematic markers or chemical fingerprints for A. sinensis and A. archangelica root oils. Chemical fingerprinting by GC/MS of A. sinensis also confirmed the misidentification of one A. archangelica sample sold in the Chinese market.


Journal of Essential Oil Research | 2000

CHEMICAL COMPOSITION OF TURKISH MYRTLE OIL

T. Özek; Betül Demirci; K. H.C. Baser

Abstract The chemical composition of essential oils from leaves and branches + leaves of Myrtus communis L. (Myrtaceae) was examined by GC/MS technique. The main components were found to be 1,8-cineole (18.3% and 10.5%), linalool (16.3% and 18.6%) and myrtenyl acetate (14.5% and 10.8%).


Chemistry of Natural Compounds | 2000

Essential oils of Nepeta species growing in Turkey.

K. H.C. Baser; N. Kirimer; M. Kürkçüoglu; Betül Demirci

Essential oils from 22Nepetaspecies growing in Turkey have been studied. Results of GC/MS analyses of the essential oils have shown that four Nepeta species contain 4aα-7α-7aα-nepetalactone as the major component. 4aα-7α-7aβ-Nepetalactone was the main constituent in N. racemosa. Seven Nepeta species contained caryophyllene oxide as the main constituent in their essential oils. 1,8-Cineole/linalool were the major components in the essential oils of six species. β-Pinene,α-terpineol,germacrene-D,and spathulenol were the main constituents in the essential oils fromN. phyllochlamys, N. viscida, N. sorgerae, andN. trachonitica, respectively.


Chemistry of Natural Compounds | 2001

CHEMICAL INVESTIGATIONS ON SOME HYPERICUM SPECIES GROWING IN TURKEY-I

S. Erken; Hulusi Malyer; Fatih Demirci; Betül Demirci; K. H.C. Baser

The chemical composition of five taxa of the genusHypericumL. obtained from herbarium specimens has been investigated.Namely, H. adenotrichum Spach(endemic),H. calycinumL.,H. cerastoides(Spach) Robson,H. montbretiiSpach, andH. perforatumL. were subjected to microdistillation to isolate the volatile compounds, which were analyzed by GC/MS.


Flavour and Fragrance Journal | 1998

The essential oils of Satureja coerulea Janka and Thymus aznavourii Velen.

G. Tümen; K. H.C. Baser; Betül Demirci; N. Ermin

Satureja coerulea Janka and Thymus aznavourii Velen. are endangered species. Thymus aznavourii is an endemic species in Turkey. Satureja coerulea has a narrow distribution in Turkey and Bulgaria. Water-distilled essential oils from the aerial parts of these species were analysed by GC–MS. The main component in the oils was identified as germacrene-D.


Journal of Vector Ecology | 2011

Essential oils of Cupressus funebris, Juniperus communis, and J. chinensis (Cupressaceae) as repellents against ticks (Acari: Ixodidae) and mosquitoes (Diptera: Culicidae) and as toxicants against mosquitoes

J. F. Carroll; Nurhayat Tabanca; Matthew Kramer; Natasha M. Elejalde; David E. Wedge; Ulrich R. Bernier; Monique Coy; James J. Becnel; Betül Demirci; K. H.C. Baser; Jian Zhang; Sui Zhang

ABSTRACT: Juniperus communis leaf oil, J. chinensis wood oil, and Cupressus funebris wood oil (Cupressaceae) from China were analyzed by gas chromatography and gas chromatography-mass spectrometry We identified 104 compounds, representing 66.8–95.5% of the oils. The major components were: &agr;-pinene (27.0%), &agr;-terpinene (14.0%), and linalool (10.9%) for J. communis; cuparene (11.3%) and &dgr;-cadinene (7.8%) for J. chinensis; and &agr;-cedrene (16.9%), cedrol (7.6%), and &bgr;-cedrene (5.7%) for C. funebris. The essential oils of C. funebris, J. chinensis, and J. communis were evaluated for repellency against adult yellow fever mosquitoes, Aedes aegypti (L.), host-seeking nymphs of the lone star tick, Amblyomma americanum (L.), and the blacklegged tick, Ixodes scapularis Say, and for toxicity against Ae. aegypti larvae and adults, all in laboratory bioassays. All the oils were repellent to both species of ticks. The EC95 values of C. funebris, J. communis, and J. chinensis against A. americanum were 0.426, 0.508, and 0.917 mg oil/cm2 filter paper, respectively, compared to 0.683 mg deet/cm2 filter paper. All I. scapularis nymphs were repelled by 0.103 mg oil/cm2 filter paper of C. funebris oil. At 4 h after application, 0.827 mg oil/cm2 filter paper, C. funebris and J. chinensis oils repelled ≥80% of A. americanum nymphs. The oils of C. funebris and J. chinensis did not prevent female Ae. aegypti from biting at the highest dosage tested (1.500 mg/cm2). However, the oil of J. communis had a Minimum Effective Dosage (estimate of ED99) for repellency of 0.029 ± 0.018 mg/cm2; this oil was nearly as potent as deet. The oil of J. chinensis showed a mild ability to kill Ae. aegypti larvae, at 80 and 100% at 125 and 250 ppm, respectively.


Chemistry of Natural Compounds | 2006

Composition of the essential oils of Lycium barbarum and L. ruthenicum fruits

A. Altintas; Müberra Koşar; N. Kirimer; K. H.C. Baser; Betül Demirci

Water-distilled essential oils from the fruits of Lycium barbarum and L. ruthenicum were analyzed by GCMS. The main components in the oil of L. barbarum were found to be hexadecanoic acid (47.5%), linoleic acid (9.1%), β-elemene (5.4%), myristic acid (4.2%), and ethyl hexadecanoate (4.0%). The essential oil of L. ruthenicum has heptacosane (14.3%), ethyl linoleate (10.0%), hexacosane (7.0%), nonacosane (6.2%), and ethyl hexadecanoate (5.8%) as the main compounds.


Chemistry of Natural Compounds | 2004

Essential oils of Sideritis species of Turkey belonging to the section Empedoclia

N. Kirimer; K. H.C. Baser; Betül Demirci; Hayri Duman

The paper summarizes the work done on the essential oil content and composition of fifty Sideritis species of Turkey belonging to the section Empedoclia. The water-distilled oils were analyzed by GC/MS. The oils were characterized as having mono- and sesquiterpenoids.


Journal of Essential Oil Research | 2005

Analysis of the Volatile Constituents of Asian Hypericum L. (Clusiaceae, Hyperidoideae) Species

Betül Demirci; K. Hüsnü Can Başer; Sara L. Crockett; Ikhlas A. Khan

Abstract Of the 57 species of the economically important genus Hypericum (St. Johns Wort; Clusiaceae) occurring in China, only a small percentage have been previously phytochemically investigated. As part of our continuing research on the phytochemistry of Hypericum, the chemical compositions of volatiles isolated from 12 Chinese species were determined. Volatile constituents were isolated by microdistillation of dried and ground aerial material from flowering plants and subsequently analyzed by GC/MS. The major component(s) were identified as follows: ar-curcumene (12.6%) and β-selinene (16.3%) in H. acmosepalum; γ-muurolene (11.3%), β-selinene (16.3%) and caryophyllene oxide (18.7%) in H. beanii; α-terpineol (11.5%) and P-pinene (29.2%) in H. calycinum; cis-eudesma-6,11-diene (11.4%) in H. choisyanum; a-pinene (10.4%) and caryophyllene oxide (12.7%) in H. forrestii; cis-β-guiaene (10.7%) and γ-muurolene (12.4%) in H. kouytchense; β-selinene (11.4%) and eudesmadienone (10.8%) in H. lancasteri; cuparene (24.8%) and γ-muurolene (16.8%) in H. leschenaultii; tricosane (13.3%) and myrcene (10.4%) in H. monogynum; β-selinene (14.7%) in H. patulum; β-selinene (18.5%) in H. pseudohenryi; and γ-muurolene (10.7%) and δ-cadinene (10.2%) in H. X moserianum.


Chemistry of Natural Compounds | 2004

Fatty Acid Composition of Seed Oils of Twelve Salvia Species Growing in Turkey

N. Azcan; A. Ertan; Betül Demirci; K. H.C. Baser

Seed oils of 12 Salvia species collected from different regions in Turkey (S. Albimaculata Hedge & Hub.-Mor., S. Candidisima Vahl., S. Cedronella Boiss., S. Cryptantha Montbret & Aucher ex Bentham, S. Forskahlei L., S. Fruticosa Miller (Sin. S. Triloba L. Fil), S. Halophila Hedge, S. Hypargeia Fisch. & Mey., S. Sclarea L., S. Tomentosa Miller, S. Tchihatcheffii (Fisch. & Mey.) Boiss., S. Virgata Jacq.) were obtained by Soxhlet apparatus using hexane. The oil yields were found to be between 2.0% and 20.9%. Fatty acids in the oils were converted to methyl esters and determined by GC/MS in methyl ester form. The main fatty acid components of S. halophila, S. Hypargeia, and S. Sclarea are unsaturated oleic, linoleic, and linolenic acids. In others except S. Candidissima, the dominant acids are oleic, linoleic and palmitic acids.

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Nurhayat Tabanca

Agricultural Research Service

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David E. Wedge

University of Mississippi

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Ikhlas A. Khan

University of Mississippi

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