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Öğe Gas Chromatographic-mass Spectrometric Analysis of Volatiles Obtained by Four Different Techniques From Salvia Rosifolia Sm., and Evaluation for Biological Activity(Elsevier, 2010) Özek, Gülmira; Demirci, Fatih; Özek, Temel; Tabanca, Nurhayat; Wedge, David E.; Khan, Shabana I.; Başer, Kemal Hüsnü Can; Duran, Ahmet; Hamzaoğlu, ErginFour different isolation techniques, conventional hydrodistillation (HD), microwave-assisted hydrodistillation (MWHD), microdistillation (MD) and micro-steam distillation-solid-phase microextraction (MSD-SPME), have been used to analyze the volatile constituents from the aerial parts of Salvia rosifolia Sm. by gas chromatography and gas chromatography coupled to mass spectrometry. HD and MWHD techniques produced quantitatively (yield, 0.39% and 0.40%) and qualitatively (aromatic profile) similar essential oils. alpha-Pinene (15.7-34.8%), 1,8-cineole (16.6-25.1%), beta-pinene (6.7-13.5%), beta-caryophyllene (1.4-5.0%) and caryophyllene oxide (1.4-4.4%) were identified as major constituents of this Turkish endemic species. Besides, the hydrodistilled oil of S. rosifolia was evaluated for antibacterial, antifungal, anticancer, antioxidant and cytotoxic activities. The hydrodistilled oil of S. rosifolia showed antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA) with a MIC value of 125 mu g/mL Other human pathogenic microorganisms (Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, Salmonella typhimurium, Staphylococcus epidermidis, Candida albicans) were also inhibited within a moderate range (MIC = 125-1000 mu g/mL). Antifungal activity of the oil was also observed against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, C. fragariae and C. gloeosporioides. No cytotoxicity was observed for S. rosifolia oil up to 25 mg/mL against malignant melanoma, epidermal, ductal and ovary carcinoma.Öğe Is there a link between premature ovarian failure and serum concentrations of vitamin D, zinc, and copper?(LIPPINCOTT WILLIAMS & WILKINS, 2013) Kebapcilar, Ayse Gul; Kulaksizoglu, Mustafa; Kebapcilar, Levent; Gonen, Mustafa Sait; Unlu, Ali; Topcu, Ali; Demirci, FatihObjective: The risk of primary ovarian insufficiency (POI) increases in association with autoimmune conditions. Adequate intake of vitamin D (vit D) and trace elements is required for the immune system to function efficiently. The aim of this study was to evaluate vit D, zinc, and copper blood levels in women with POI who had given birth to at least one child and in women with normal menstrual cycles. Methods: This was a cross-sectional, case-control study involving 63 participants divided into two groups: the study group, which is composed of 35 women with POI, and the control group, which is composed of 28 women with normal menstrual cycles. Serum concentrations of zinc, vit D, and copper were determined for each participant. Results: Women with POI had significantly higher serum copper levels and copper-to-zinc ratio but significantly lower serum vit D and zinc levels when compared with the healthy control group. Serum follicle-stimulating hormone levels were inversely correlated with zinc and vit D levels and positively correlated with the copper-to-zinc ratio and copper levels. Vit D levels were inversely correlated with follicle-stimulating hormone levels, copper-to-zinc ratio, and copper levels and positively correlated with zinc levels. Conclusions: Most women with POI are deficient in vit D. Zinc, copper, and vit D seem to correlate with hormonal status in the participants. The present study may generate hypotheses for future studies that will investigate the possible mechanisms behind alterations in trace elements and vit D deficiency in women with POI and whether these changes could be used to screen for the risk of developing POI.Öğe Prenylated polyphenolic compounds from Glycyrrhiza iconica and their antimicrobial and antioxidant activities(ELSEVIER SCIENCE BV, 2015) Kirmizibekmez, Hasan; Uysal, Gorkem Berk; Masullo, Milena; Demirci, Fatih; Bagci, Yavuz; Kan, Yuksel; Piacente, SoniaA new prenylated isoflavan, iconisoflavan (1), and a new prenylated isoflav-3-ene, iconisoflaven (2) were isolated from the roots of Glycyrrhiza iconica together with four known ones namely (3S)-licoricidin (3), licorisoflavan A (4), topazolin (5) and glycycoumarin (6). The structures were elucidated on the basis of extensive spectroscopic analysis including 1D and 2D NMR as well as HR-MS. Furthermore, the absolute configurations of compounds 1,3 and 4 were established by electronic circular dichroism (ECD). All the isolated compounds (1-6) were evaluated for their in vitro antimicrobial activities against five pathogenic bacteria and one yeast (Candida albicans) using an in vitro microdilution method. Compounds 1 and 3-5 displayed significant activity against Salmonella typhimurium ATCC 13311 with MIC values ranging from 2 to 8 mu g/mL. Additionally, all compounds were screened for their in vitro free radical scavenging activities using an in vitro microdilution DPPH assay spectrofotometrically. The tested compounds exhibited IC50 values in the range of 0.18-0.56 mg/mL, suggesting an activity comparable with that of ascorbic acid (IC50: 0.07 mg/mL). To the best of our knowledge, the present study constitutes the first phytochemical and bioactivity investigation on G. iconica. (C) 2015 Elsevier B.V. All rights reserved.Öğe Treatment of recurrent hypoglycemia with plasmapheresis and steroid in nondiabetic patient(PERGAMON-ELSEVIER SCIENCE LTD, 2013) Kulaksizoglu, Mustafa; Gonen, Mustafa Sait; Kebapcilar, Levent; Sahin, Fatih; Demirci, Fatih; Topcu, AliWe recently encountered a 35-year old man who suffered from frequent hypoglycemia. His blood test revealed the presence of high and suppressed level of insulin with supressed C-peptide levels, hypothalamic-pituitary axis was normal response in hypoglycemia and negative for anti-insulin antibody. Endocrinological and imaging data eliminated the possibility of insulinoma. His symptoms responded well to the therapy of prednisolone (60 mg/day) and plasmapheresis. We followed up the patient over the subsequent 6 months without remarkable lesions. He has had no further recurrences of hypoglycemia. We believe that the antiinsulin receptor antibody might have induced hypoglycemia in this patient. (C) 2012 Elsevier Ltd. All rights reserved.
