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Öğe Alkaloids from Galanthus fosteri(Elsevier Science Bv, 2016) Emir, Ahmet; Emir, Ceren; Bozkurt, Buket; Onur, Mustafa Ali; Bastida, Jaume; Somer, Nehir UnverThree new alkaloids, oxoincartine, 3,11-O-diacetyl-9-O-demethylmaritidine and 11-O-acetyl-9-O-demethylmaritidine together with seven known compounds namely, incartine, galanthamine, galanthine, 9-O-methylpseudolycorine, N,O-dimethylnorbelladine, hordenine and vittatine were isolated from Galanthus fosteri Baker (Amaryllidaceae). Their structures were elucidated by spectroscopic analyses (UV, IR, MS, CD and 1D/2D NMR). Cholinesterase inhibitory activity potentials of the compounds were also determined. (C) 2016 Phytochemical Society of Europe. Published by Elsevier Ltd. All rights reserved.Öğe Antiproliferative activity of Amaryllidaceae alkaloids from Leucojum aestivum L. of Turkish origin(Georg Thieme Verlag Kg, 2023) Baş, Yasemin; Entezari, Bita; Orhan, Hande Gürer; Bozkurt, Buket; Somer, Nehir Unver; Kaya, Gülen İrem[No abstract available]Öğe Antiprotozoal alkaloids from Galanthus trojanus(Elsevier Science Bv, 2011) Kaya, Gulen Irem; Sarikaya, Buket; Onur, Mustafa Ali; Somer, Nehir Unver; Viladomat, Francesc; Codina, Carles; Bastida, Jaume; Lauinger, Ina L.; Kaiser, Marcel; Tasdemir, DenizTwo new alkaloid N-oxides, 1-O-acetyldihydromethylpseudolycorine N-oxide, and 11-hydroxyvittatine N-oxide, ten known alkaloids; arolycoricidine, haemanthamine, O-methylnorbelladine, narcidine, dihydrolycorine, 8-O-demethylmaritidine, stylopine and protopine, nicotinic acid and tyramine were isolated from Galanthus trojanus A. P. Davis & N. Ozhatay (Amaryllidaceae). The chemical structures of the isolates were elucidated by UV, IR, MS, CD, 1D and 2D NMR experiments. The in vitro antiprotozoal and cytotoxic potentials of the compounds were also evaluated. (C) 2011 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.Öğe Application of HPLC-DAD for the quantification of Lycorine in Galanthus elwesii Hook(Univ Sao Paulo, Conjunto Quimicas, 2017) Emir, Ahmet; Emir, Ceren; Bozkurt, Buket; Onur, Mustafa Ali; Somer, Nehir Unver; Kaya, Gulen IremIn the present study, a reversed-phase high-performance liquid chromatographic method has been used for the quantitative determination of lycorine in the aerial parts and bulbs of G. elwesii Hook. A simple method for the extraction of lycorine in low mass plant samples was employed utilizing pre-packed columns with diatomaceous earth (Extrelut (R)). The chromatographic separation was performed using an isocratic system with a mobile phase of trifluoroacetic acid-water-acetonitrile (0.01:92.5:7.5,v/v/v) applied at a flow rate 1 mL min(-1) using diode array detector. The content of lycorine in the bulbs and aerial parts of G. elwesii collected from Demirci (Manisa) was found as 0.130 and 0.162 %, respectively. Additionally, in the bulbs of the specimens collected from Sogucak (Balikesir), lycorine was quantified as 0.055 %, whereas in the aerial parts, it was determined as 0.006 %. The method was validated partially with respect to system specificity, linearity, accuracy, precision, limits of detection (LOD) and quantitation (LOQ). Validation procedures displayed that the method was specific, accurate and precise.Öğe A Brief Up-to-Date Overview of Amaryllidaceae Alkaloids: Phytochemical Studies of Narcissus tazetta subsp. tazetta L., Collected in Turkey(Sage Publications Inc, 2019) Karakoyun, Cigdem; Masi, Marco; Cimmino, Alessio; Onur, Mustafa Ali; Somer, Nehir Unver; Kornienko, Alexander; Evidente, AntonioA brief up-to-date overview on the isolation, and chemical and biological characterization of new and known alkaloids from different Amaryllidaceae species, including Brunsvigia, Crinum, Cyrtanthus, Narcissus, and Nerine genera, was reported. Furthermore, the isolation and chemical characterization of alkaloids extracted from bulbs of Narcissus tazetta subsp. tazetta L. collected from Mula, Turkey were described.Öğe Chemical Composition and Antimicrobial Activity of Essential Oils from the Aerial Parts of Salvia pinnata L.(Acg Publications, 2015) Somer, Nehir Unver; Sarikaya, Buket Bozkurt; Erac, Bayri; Kaynar, Erdem; Kaya, Gulen Irem; Onur, Mustafa Ali; Demirci, Betul; Baser, Kemal Husnu CanThe composition of the essential oils obtained by hydrodistillation from the aerial parts of Salvia pinnata L. (Labiatae), collected during flowering and fruiting periods, were analyzed by GC and GC-MS. 37 compounds were identified representing 96.1 % of the essential oil obtained from the plant material collected during flowering period. 30 compounds were detected constituting 94.7 % of the essential oil of the plant material collected in fruiting period. The main components of the essential oils were characterized as bornyl acetate, camphor, camphene, bornyl formate, a-pinene and borneol. The oils were screened for antimicrobial activity by the micro-dilution assay against standard bacteria (Escherichia coli, Salmonella enterica, Staphylococcus aureus, Enterococcus faecalis) and yeast (Candida albicans and Candida parapsilosis). Both of the oils showed antimicrobial activity against the tested organisms.Öğe The Effects of Arolycoricidine and Narciprimine on Tumor Cell Killing and Topoisomerase Activity(Acg Publications, 2012) Sarikaya, Buket Bozkurt; Zencir, Sevil; Somer, Nehir Unver; Kaya, Gulen Irem; Onur, Mustafa Ali; Bastida, Jaume; Berenyi, Agnes; Zupko, Istvan; Topcu, ZekiIn this study, narciprimine and arolycoricidine were isolated from G. rizehensis Stern (Amaryllidaceae). The structures of the alkaloids were elucidated by spectroscopic methods (1D NMR, EI-MS). Due to the previous reports on anti-cancer activity of this group of alkaloids, we investigated their effects on DNA topoisomerase reactions, which are known as the cellular targets of a number of chemotherapeutical drugs. The results revealed that arolycoricidine and narciprimine were effective in both type I and type II DNA topoisomerase reactions in a dose-dependent manner. Topoisomerase-interfering ability of these alkaloids partially correlated with cytostaticity assays, using HeLa (cervix adenocarcinoma), MCF7 (breast adenocarcinoma) and A431 (skin epidermoid carcinoma) cells. Our results are discussed in relation to the potential significance of these alkaloids in the course of drug-development studies.Öğe GC-MS Investigation and Acetylcholinesterase Inhibitory Activity of Galanthus rizehensis(Walter De Gruyter Gmbh, 2013) Sarikaya, Buket Bozkurt; Somer, Nehir Unver; Kaya, Gulen Irem; Onur, Mustafa Ali; Bastida, Jaume; Berkov, StrahilGC-MS (gas chromatography-mass spectrometry) analyses of alkaloids in the aerial parts and bulbs of Galanthus rizehensis Stern (Amaryllidaceae), collected during two different vegetation periods, was performed. Twenty three alkaloids were identified in four different alkaloid extracts. Acetylcholinesterase (AChE) inhibitory activities of the alkaloid extracts were tested. Both the highest alkaloid diversity and the most potent inhibitory activity (IC50 12.94 mu g/ml) were obtained in extracts from the bulbs of G. rizehensis collected during the fruiting period.Öğe GC-MS Investigation and Acetylcholinesterase Inhibitory Activity of Galanthus rizehensis(Walter De Gruyter Gmbh, 2013) Sarikaya, Buket Bozkurt; Somer, Nehir Unver; Kaya, Gulen Irem; Onur, Mustafa Ali; Bastida, Jaume; Berkov, StrahilGC-MS (gas chromatography-mass spectrometry) analyses of alkaloids in the aerial parts and bulbs of Galanthus rizehensis Stern (Amaryllidaceae), collected during two different vegetation periods, was performed. Twenty three alkaloids were identified in four different alkaloid extracts. Acetylcholinesterase (AChE) inhibitory activities of the alkaloid extracts were tested. Both the highest alkaloid diversity and the most potent inhibitory activity (IC50 12.94 mu g/ml) were obtained in extracts from the bulbs of G. rizehensis collected during the fruiting period.Öğe GC-MS Investigation of Amaryllidaceae Alkaloids in Galanthus xvalentinei nothosubsp subplicatus(Sage Publications Inc, 2013) Sarikaya, Buket Bozkurt; Berkov, Strahil; Bastida, Jaume; Kaya, Gulen Irem; Onur, Mustafa Ali; Somer, Nehir UnverA GC-MS analysis of alkaloids in the aerial parts and bulbs of Galanthus xvalentinei nothosubsp. subplicatus was performed for the first time. Totally, twenty-six alkaloids were identified, of which tazettine and galanthindole were the major ones. Acetylcholinesterase inhibitory activity of the alkaloidal extracts was determined using modified in vitro Ellman's method. Significant anticholinesterase activity was observed in the tested samples (bulbs: IC50 = 21.3 mu g/mL, aerial parts: IC50 = 16.3 mu g/mL).Öğe GC-MS Investigation of Amaryllidaceae Alkaloids in Galanthus xvalentinei nothosubsp subplicatus(Sage Publications Inc, 2013) Sarikaya, Buket Bozkurt; Berkov, Strahil; Bastida, Jaume; Kaya, Gulen Irem; Onur, Mustafa Ali; Somer, Nehir UnverA GC-MS analysis of alkaloids in the aerial parts and bulbs of Galanthus xvalentinei nothosubsp. subplicatus was performed for the first time. Totally, twenty-six alkaloids were identified, of which tazettine and galanthindole were the major ones. Acetylcholinesterase inhibitory activity of the alkaloidal extracts was determined using modified in vitro Ellman's method. Significant anticholinesterase activity was observed in the tested samples (bulbs: IC50 = 21.3 mu g/mL, aerial parts: IC50 = 16.3 mu g/mL).Öğe HPLC - DAD Analysis of Lycorine in Amaryllidaceae Species(Natural Products Inc, 2010) Kaya, Gulen Irem; Cicek, Derya; Sarikaya, Buket; Onur, Mustafa Ali; Somer, Nehir UnverLycorine, the most frequent alkaloid found in Amaryllidaceae plants, has been proven to have various biological activities. Therefore, it is important to quantify this compound in Amaryllidacaeae species. In this study, a reversed-phase high-performance liquid chromatographic method has been used and validated for the determination of lycorine in Amaryllidaceae plants. A simple method for the extraction of lycorine in low-mass plant samples was employed utilizing columns pre-packed with diatomaceous earth (Extrelut (R)). This method was applied to the aerial parts and bulbs of Sternbergia sicula Tineo ex Guss., S. lutea (L.) Ker-Gawl. ex Sprengel and Pancratium maritimum L. (Amaryllidaceae) collected during two different vegetation periods. The chromatographic separation was performed using an isocratic system with a mobile phase of trifluoroacetic acid-water-acetonitrile (0.01:90:10) applied at a flow rate 1 mL min(-1) using diode array detector. Validation procedures showed that the method was specific, accurate and precise. The amount of lycorine in S. sicula samples ranged between 0.10-0.53%, whereas in those of S. lutea and P. maritimum, the range was 0.19-0.40% and 0.05-0.14%, respectively.Öğe Phytochemical investigation of Galanthus woronowii(Pergamon-Elsevier Science Ltd, 2013) Sarikaya, Buket Bozkurt; Kaya, Gulen Irem; Onur, Mustafa Ali; Bastida, Jaume; Somer, Nehir UnverÖğe Quantitative analysis of lycorine in Galanthus alpinus Sosn. var. alpinus by HPLC-DAD(Istanbul Univ, Fac Pharmacy, 2018) Emir, Ceren; Somer, Nehir UnverIn this study, a reversed-phase, high pressure liquid chromatography (RP-HPLC) method was applied in the quantitative analysis of lycorine in the aerial parts and bulbs of Galanthus alpinus Sosn. var. alpinus collected from Rize during the flowering and fruiting seasons. A simple method to extract lycorine from the plant specimens was performed, using pre-packed columns with diatomaceous earth (Extrelut (R)). The chromatographic separation was achieved employing an isocratic system with a mobile phase including trifluoroacetic acid -water-acetonitrile (0.01:95:51 measured at a flow rate of 1 ml/min using a diode array detector (DAD). The lycorine content in the bulbs during the flowering and fruiting seasons was detected as 0.01576 and 0.02351 %, respectively. Also, validation studies showed that the method was specific, accurate and precise.Öğe Quantititative Determination of Lycorine and Galanthamine in Galanthus trojanus and G. cilicicus by HPLC-DAD(Natural Products Inc, 2014) Kaya, Gulen Dem; Polat, Derya Cicek; Sarikaya, Buket; Onur, Mustafa Ali; Somer, Nehir UnverLycorine and galanthamine have various biological activities. A reliable HPLC method coupled with DAD detection was developed and validated for the determination of galanthamine and lycorine in Galanthus trojanus and G. cilicicus. A simple method for the extraction of the alkaloids in low-mass plant samples was employed utilizing columns pre-packed with diatomaceous earth (Extrelut (R))). This method was applied to the aerial parts and bulbs of G. trojanus and G. cilicicus (Amaryllidaceae) collected during the flowering season. The chromatographic separation was performed using an isocratic system with a mobile phase of trifluoroacetic acid-water-acetonitrile (0.01:92.5:7.5) applied at a flow rate of 1 mL min(-1) and using a diode array detector. Validation procedures showed that the method was specific, accurate and precise. The highest amount of lycorine (0.012 %) was detected in the bulbs of G. trojanus collected from Can (Canakkale), whereas the aerial parts of this species collected from Bayramic (canakkale) was not found to contain this alkaloid. In G. cilicicus samples, lycorine was only determined in the bulbs, giving yields of 0.004 %; galanthamine yields were between 0.015-0.016 %, but none of the G. trojanus samples contained this latter alkaloid.
