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Öğe Arsenic speciation in water and biota samples at trace levels by ion chromatography inductively coupled plasma-mass spectrometry(Taylor & Francis Ltd, 2017) Firat, Merve; Bakirdere, Sezgin; Sel, Sabriye; Chormey, Dotse Selali; Elkiran, Omer; Erulas, Fatih; Turak, FatmaA sensitive, reliable, simple and rapid analytical method was developed for the determination of arsenite [As(III)], arsenate [As(V)] and arsenobetaine (AsB) species using ion chromatography combined with inductively coupled plasma-mass spectrometry (IC-ICP-MS). Inorganic and organic arsenic species were separated with an anion exchange column (Dionex AS9) and a 50mM sodium bicarbonate mobile phase (pH 10) at a flow rate of 1.0mL min(-1.) %RSD values were found to be lower than 5.1% for all arsenic species. The limits of detection (LOD) obtained for As(III), As(V) and AsB were 16.5 ng L-1, 14.1 ng L-1 and 6.2 ng L-1, respectively. The developed analytical method was tested using AsB certified reference material (NMIJ CRM 7901-a), and spring water certified reference material (UME CRM 1201) for accuracy check. This method was applied for the quantitative determination of arsenic species in different water samples and chicken samples as a solid matrix.Öğe Biological activities and chemical composition of essential oil of Achillea maritima (L.) Ehrend. & YPGuo(Taylor & Francis Inc, 2023) Elkiran, Omer; Avsar, Cumhur; Bagci, EyupThis study aimed to describe the chemical composition of the essential oil (EO) of stems, leaves and flowers of A. maritima collected from Turkey, and verify its antimicrobial and antioxidant properties. The EO was analyzed by GC-FID and GC-MS. Fifty-nine compounds representing to 98.1% of the EO were identified. The antimicrobial activities were determined against seven bacteria and two yeast species by using disc diffusion and MIC techniques. According to the results, it was observed that there was no effect of the EO against Gram-positive bacteria. The EO showed a low effect (8-9 mm) against Gram-negative bacteria, but the EO had a high effect (20-22 mm) against the tested fungi. In addition, according to the MIC test results, the EO presented effects against C. krusei, C. parapsilosis at a concentration of 50 mu l/ml. The antioxidant activity of the EO was determined as IC50 = 31.9 mu l/mL.Öğe CHEMICAL COMPOSITION AND BIOLOGICAL ACTIVITIES OF ESSENTIAL OILS OF ENDEMIC THYMUS LEUCOSTOMUS HAUSSKN. ET VELEN(Bangladesh Botanical Soc, 2020) Elkiran, Omer; Avsar, CumhurThe chemical composition, antimicrobial and antioxidant properties of the essential oils from the leaves of endemic Thymus leucostomus naturally grown in Turkey were investigated and chemical differences were discussed by means of chemotaxonomy. Twenty-six components were identified representing 98.8% of the oils. The main compounds in the essential oil of T. leucostomus were: o-cymene (30.6%), carvacrol (9.6%), thymol methyl ether (7.2%), limonene (6.8%). Essential oil was screened for their antimicrobial activities against 7 bacteria and 2 yeast species by using disc-diffusion and MIC procedure. The essential oil showed higher effectiveness against all the tested bacteria and yeast. The extract was observed to be much more effective in Gram-positive bacteria (especially, S. aureus ATCC 6538). In vitro antioxidant activity based on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical was evaluated for the essential oil, and it was found that the essential oil had good antioxidant activity in the range of the IC50 = 5.42 +/- 0.8 mu g/ml.Öğe Chemical composition and biological activities of the essential oil from the leaves of vaccinium Myrtillus L(Bangladesh Botanical Society, 2020) Elkiran, Omer; Avşar, CumhurThe chemical composition, antimicrobial and antioxidant properties of the essential oil (EO), obtained from the leaves of Vaccinium myrtillus naturally grown in the northernmost of Turkey were determined by GC and GC-MS and chemical differences were discussed with the help of chemotaxonomy. The leaves of the plant samples were hydro-distilled to produce oil in the yields of 1%. Nineteen components were identified representing 96.4% of the oil. The main compounds in the EO of V. myrtillus were; 1,8-cineole (38.6%), αpinene (21%), linalool (19.5%), α-terpineol (5.8%). The EO extract was screened for their antimicrobial activities against the 9 bacteria and 3 yeast species by using disc-diffusion and MIC procedure. The EO extract displayed more effective against all the tested bacteria (especially, S. aureus ATCC 6538 and MRSA) and yeast (only C. krusei). The MIC values of sample against tested microorganisms were found to be in the range of 320 to ≥1280 µg/ml. The most effective MIC values were observed against the S. aureus and MRSA (320 µg/ml). In vitro the antioxidant activity based on the 1,1-diphenly-2-picrylhydrazyl (DPPH) free radical was evaluated for the EO extract, and it was found that the extract had good antioxidant activity in the range of the IC50 = 583.4 ±11 µg ml. Antibacterial and antioxidant activities of the EO from the leaves of V. myrtillus has been reported for the first time. © 2020 Bangladesh Botanical Society. All rights reserved.Öğe CHEMICAL COMPOSITION AND BIOLOGICAL ACTIVITIES OF THE ESSENTIAL OIL FROM THE LEAVES OF VACCINIUM MYRTILLUS L.(Bangladesh Botanical Soc, 2020) Elkiran, Omer; Avsar, CumhurThe chemical composition, antimicrobial and antioxidant properties of the essential oil (EO), obtained from the leaves of Vaccinium myrtillus naturally grown in the northernmost of Turkey were determined by GC and GC-MS and chemical differences were discussed with the help of chemotaxonomy. The leaves of the plant samples were hydro-distilled to produce oil in the yields of 1%. Nineteen components were identified representing 96.4% of the oil. The main compounds in the EO of V. myrtillus were; 1,8-cineole (38.6%), alpha-pinene (21%), linalool (19.5%), alpha-terpineol (5.8%). The EO extract was screened for their antimicrobial activities against the 9 bacteria and 3 yeast species by using disc-diffusion and MIC procedure. The EO extract displayed more effective against all the tested bacteria (especially, S. aureus ATCC 6538 and MRSA) and yeast (only C. krusei). The MIC values of sample against tested microorganisms were found to be in the range of 320 to >1280 mu g/ml. The most effective MIC values were observed against the S. aureus and MRSA (320 mu g/ml). In vitro the antioxidant activity based on the 1,1-diphenly-2-picrylhydrazyl (DPPH) free radical was evaluated for the EO extract, and it was found that the extract had good antioxidant activity in the range of the IC50 = 583.4 +/- 11 mu g ml. Antibacterial and antioxidant activities of the EO from the leaves of V. myrtillus has been reported for the first time.Öğe Chemical Composition of the Essential Oil of Heracleum platytaenium BOISS. (Apiaceae) Growing Wild in Turkey(2018) Elkiran, Omer; Gul, FatihIn this study, the essential oils of Heracleum platytaenium (Apiaceae) species in Sinop region of northern Turkey were investigatedand 27 components were identified by GC, GC-MS. Essential oils were obtained by Clevenger-type hydrodistilled from the aerialparts of plants collected from the natural habitats. The essential oils yield is very low and 0.5 (v/w). Twenty seven constituents werecomprised the 98.1% of the total essential oil extracted from the Heracleum platytaenium. The predominant compounds of Heracleumplatytaenium were as Limonene (30.8%), Terpinolene (17.9%), β-Pinene (16.3%) and Ocimene (12.6%). The results were discussed inview of chemotaxonomy and natural products.Öğe Chemical Composition of the Essential Oil of Thymus longicaulis C. Presl. subsp. longicaulis(Pamukkale University, 2022) Elkiran, OmerIn this study, the chemical composition of the essential oils obtained from the aerial parts of Thymus longicaulis subsp. longicaulis naturally grown in Turkey were analyzed by GC and GC-MS and chemical differences in terms of chemotaxonomy were discussed. The main compounds in the essential oils of T. longicaulis subsp. longicaulis essential oils were 1,8-cineole (30.1%), linalool (18.0%), β-pinene (17.3%) and (E)-β-ocimene (%12.6%) Hierarchical cluster analysis was performed by examining essential oil studies of 34 samples belonging to the genus Thymus, including the Sinop sample. The results of the study were discussed with other taxa belonging to the genus. © IJSM 2022.Öğe CONSTITUENTS OF ESSENTIAL OILS FROM LEAVES AND SEEDS OF LAURUS NOBILIS L.: A CHEMOTAXONOMIC APPROACH(Bangladesh Botanical Soc, 2018) Elkiran, Omer; Akbaba, Emel; Bagci, EyupIn the present study, chemical compositions of essential oils from seeds and leaves of laurel (Laurus nobilis L.) were evaluated using GC-GC/MS system. Sixty nine different compounds were identified constituting 86.7% of the total oil from the seed, while 76 compounds were determined, constituting 95.8% of the total oil extracted from the leaves. The major compounds of essential oil from laurel seeds included eucalyptol (17.2%), alpha-terpinyl acetate (9.0%), caryophyllene oxide (6.1%), spathulenol (5.0%) and methyl eugenol (4.2%), constituting 41.5% of the total oil. However, eucalyptol (18.0%), alpha-terpinyl acetate (13.1%), sabinene (7.8%), alpha-pinene (4.5%), 2 (4-methoxyphenyl)-N,N,2-trimethyl-1-pyrroline (4.4%) were identified as the major compounds in the oil from laurel leaves, constituting 47.8% of the total oil. Eucalyptol and aterpinyl acetate, belonging to monoterpenoids, were determined in the highest concentrations within both oils. However, the other principle compounds differ between the two volatile oils.Öğe Exploration of UHPLC-ESI-QTOF-MS Profiles and the Neuroprotective, Antidiabetic, Antioxidant and Cytotoxic Effects of Extracts from Achillea maritima (L.) Ehrend. & Y.P.Guo (Asteraceae) Collected in Türkiye(Springer, 2025) Ahmed, Shakeel; Zengin, Gokhan; Fernández-Ochoa, Álvaro; de la Luz Cádiz-Gurrea, Maria; Leyva-Jiménez, Francisco Javier; Elkiran, Omer; Cakilcioglu, UgurThe current study investigated the chemical composition, antioxidant activity, enzyme inhibition, and cytotoxic activities of extracts from Achillea maritima, a wild medicinal plant used for various therapeutic purposes. The antioxidant activities were assayed through different assays like DPPH, ABTS, CUPRAC, FRAP, and phosphomolybdenum, whereas in enzyme inhibition studies, cholinesterase, tyrosinase, α-amylase, and α-glucosidase were assayed. Cytotoxicity studies are conducted on S17, RAW, and HepG2 to assess its selectivity and effectiveness. Chemical profiling by UHPLC-ESI-QTOF-MS revealed multiple bioactive compounds in the extracts. Polar solvents (ethanol, ethanol/water, and water) resulted in high concentrations of phenolic acids as well as chlorogenic and caffeoylquinic acids, as well as flavonoids like vicenin and apigenin. On the other, the nonpolar (hexane extract) was rich in octadecatrienoic acid hydroperoxy and hydroxyoctadecatrienic acid. Among these, the water extract contained the highest phenolic content of 32.26 mg GAE/g, while the ethyl acetate extract was the richest in flavonoids, with 7.83 mg RE/g. In the antioxidant studies, the water and ethanol/water extracts consistently display the most potent activities, thus indicating their significant free radical scavenging and metal chelation abilities. The studies on enzyme inhibitions showed remarkable BChE inhibitory activities of the ethanol extract in 12.50 mg GALAE/g, thus showing potential in managing disease conditions related to cholinesterase. Tyrosinase inhibition was significant by the ethanol extract, presenting 55.59 mg KAE/g. The ethyl acetate extract exhibited the most potent inhibitory activity against α-amylase with 0.66 mmol ACAE/g, while ethanol extract showed significant inhibition of α-glucosidase with 4.35 ACAE/g. Cytotoxicity results showed that the water extract was most effective against the HepG2 cancer cell line by reducing cell viability to 38.4% at high doses while preserving low toxicity against normal cells, as observed by high viability percentages in S17 and RAW cell lines. These results highlight the usefulness of A. maritima extracts in nutraceutical, pharmaceutical, and cosmeceutical applications. © The Author(s) 2025.Öğe POLLEN MORPHOLOGY AND ITS RELATIONSHIP TO THE TAXONOMY OF THE SOME TAXA OF HELICHRYSUM GAERTNER (ASTERACEAE) IN TURKEY(Pakistan Botanical Soc, 2017) Elkiran, Omer; Bagci, Eyup; Evren, A. HarunPalynological studies of Helichrysum chionophilum, Helichrysum noeanum, Helichrysum arenarium subsp. aucheri, Helichrysum graveolens, H. plicatum subsp. plicatum and H. plicatum subsp. polyphyllum (Asteraceae) from Turkey have been carried out. H. chionophilum, H. noeanum and H. arenarium subsp. aucheri are endemics to Turkey. Pollen features of both taxa were observed with the Light and Scanning Electron Microscopy (SEM). The pollen type of both taxa were determined as tricolporate, pollen shapes were spheroidal and oblate-spheroidal, reticular pollen ornamentation was observed. The studies show that the pollen of the six taxa are very similar regarding pollen shapes, apertures, and ornamentation, but may be distinguished by colpus length (Clg), pore width (Plt) and pore length (Plg). The findings obtained from the study are discussed with each other and the genus patterns.Öğe Prediction of the Binding to the Nuclear Factor NF-Kappa-B by Constituents from Teucrium polium L. Essential Oil(Mdpi, 2025) de Barros, Renilson Castro; da Costa, Renato Araujo; Guenane, Nesrine; Bakchiche, Boulanouar; Benaceur, Farouk; Elkiran, Omer; Farias, Suelem Daniella PinhoTeucrium polium L. is a plant with various claims of ethnobotanical use, primarily for inflammatory diseases. Chemical studies have already isolated different types of terpenes from the species, and studies have established its pharmacological potential. The present study evaluates the components of T. polium essential oil cultivated in the Algerian Saharan Atlas. GC-MS identified the major components as fenchone (31.25%), 3-carene (15.77%), cis-limonene oxide (9.77%), and myrcene (9.15%). In the in silico prediction, molecules with more than 1% abundance were selected. Regarding Lipinski's rule, all molecules followed the rule. All molecules were found to be toxic in at least one model, with some molecules being non-genotoxic (6, 8, 10, 11, 12, 13) and others being non-mutagenic (5, 7, 9, 14). Three molecules were selected that showed the best results in pharmacokinetic and toxicity studies: the molecules that did not present carcinogenic potential (7-myrtenal; 9-myrtenol; 14-verbenol). The molecular target was established, and it seems that all three bound to the nuclear factor NF-kappa-B. Based on the docking and molecular dynamics results, these molecules have potential as anti-inflammatory and antitumor therapies, with further in vitro and in vivo studies needed to evaluate their activity and toxicity.Öğe The chemical composition and biological activities of essential oil from the aerial parts of Eryngium maritimum L. (Apiaceae)(Taylor & Francis Ltd, 2023) Elkiran, Omer; Avsar, Cumhur; Veyisoglu, Aysel; Bagci, EyupThis study aimed to describe the chemical composition of the Essential Oil (EO) of the aerial parts of E. maritimum, and verify its antimicrobial and antioxidant properties. The EO chemical characterization was simultaneously obtained by GC/FID and GC/MS. Thirty-one compounds corresponding to 93.3% of the EO were identified in the EO of E. maritimum. Spathulenol (22.0%), aromadendrene (18.3%), humulene epoxide (6.6%), and beta-humulene (4.8%) were the main compounds of the EO. The antimicrobial activities were determined against 3 gram-positive bacteria, 4 gram-negative bacteria, and 2 yeast species by using disc-diffusion and MIC techniques. EO showed a low effect (8-11 mm) against all tested bacteria and yeasts. Additionally, EO extract against Staphylococcus aureus ATCC 6538 and Shigella flexneri ATCC 12022 from tested microorganisms presented a MIC value at mu l/ml concentration. The antioxidant activity of the EO was determined as IC50=16.8 +/- 1.65 mu l/mL. To the best of our knowledge, this is the first report on the chemical composition and biological activities of E. maritimum EO in Turkey.Öğe THE COMPARATIVE MORPHOLOGICAL, ANATOMICAL AND PALYNOLOGICAL STUDIES ON THE GENUS HELLEBORUS (RANUNCULACEAE) GROWING IN TURKEY(Pakistan Botanical Soc, 2023) Elkiran, OmerIn the present study, the morphological, anatomical, and palynological characteristics of H. orientalis Lam. and H. vesicarius Aucher (endemic) were studied and compared. The root structures, branching shape, the distance between internodes, basal and stem leave dimensions, detailed descriptions of leaves, detailed new morphological characters of flowers and sepals were added to plant descriptions. Their anatomical structures were visualized under a light microscope and compared for the first time with detailed micro-anatomical measurements. Pollen images were shown for the first time by using the Scanning Electron Microscopy. It was found that the pollen types were tricolpate and tricolporate (rarely tricolpate), their shapes were subprolate and prolate-spheroidal, and their ornamentations were reticulate and microreticulate-foveolate.Öğe The Essential Oils of Laurus nobilis L. and Molecular-Spectroscopic Analysis for 1,8-Cineole(Sakarya University, 2021) Elkiran, Omer; Karakaya, MustafaIn the present study, the chemical composition of the essential oils obtained from leaves of Laurus nobilis naturally grown in Turkey were evaluated using by GC and GC-MS and chemical differences were depated in means of chemotaxonomy. The leaves of the plant samples were hydro-distilled. Twenty components were identified representing 99.3% of the oils, The main compounds in the essential oils were; 1,8-cineole (%48.47), β-pinene (%14.45), linalool (%8.15) and α-pinene (%5.97). In addition, the complexation energies, chemical shifts of the carbon and hydrogen atoms in the 1,8-cineole structures were calculated by ab initio theoretical approaches. The performances of the B3LYP and M06 functionals were tested on carbon and hydrogen complexation energies of the investigated compound. The electronegativity effect of oxygen and solvent effect on complexation energy of the carbons and hydrogens were evaluated with the results obtained. © 2021, Sakarya University. All rights reserved.
