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Characterization Of Lipids And Fatty Acid Methyl Ester Contents In Leaves And Roots Of Crocus Vallicola, Nuretti̇n Yayli, Zerri̇n Kiran, Hasan Seymen, Hasan Genç, Mustafa Küçüki̇slamoğlu Jan 2001

Characterization Of Lipids And Fatty Acid Methyl Ester Contents In Leaves And Roots Of Crocus Vallicola, Nuretti̇n Yayli, Zerri̇n Kiran, Hasan Seymen, Hasan Genç, Mustafa Küçüki̇slamoğlu

Turkish Journal of Chemistry

The chemical composition of the fatty acids methyl esters (FAMEs) and other lipids in leaves and roots of Crocusvallicola were analyzed by gas chromatography-mass spectrometry(GC-MS). In this work, twenty-eight compounds, including 22 FAMEs, 1 aldehyde, 3 hydrocarbons (substitute alkane and alkene), 2 alcohols in the leaves and twenty-one compounds (17 FAMEs, 1 anhydride, 1 substitute alcohol, 1 ketone, 1 substitute amide) in the roots were identified by GC-MS from C. vallicola. The FAMEs in leaves and roots were highly similar; only the amounts of the esters were different. Key Words: Crocus vallicola, leaves, roots, FAMEs


The Cytogenetic Effects Of Sodium Metabisulfite, A Food Preservative In Root Tip Cells Of Allium Cepa L., Eyyüp Rencüzoğullari, Ahmet Kayraldiz, Hasan Basri̇ İla, Tonguz Çakmak, Mehmet Topaktaş Jan 2001

The Cytogenetic Effects Of Sodium Metabisulfite, A Food Preservative In Root Tip Cells Of Allium Cepa L., Eyyüp Rencüzoğullari, Ahmet Kayraldiz, Hasan Basri̇ İla, Tonguz Çakmak, Mehmet Topaktaş

Turkish Journal of Biology

The effects of sodium metabisulfite (SMB) on mitosis were investigated in Allium cepa L. The roots of A. cepa were treated with SMB concentrations of 7.5 mg/lt, 15 mg/lt and 30 mg/lt for 10- and 20-hour treatment periods. SMB significantly decreased the mitotic index (MI) at all concentrations and treatment periods. While the decreasing of the MI was dose-dependent at 10 hours treatment time, SMB increased the mitotic abnormalities dose dependently.


Production Of Single-Cell Protein From Ram Horn Hydrolysate, Esabi̇ Başaran Kurbanoğlu Jan 2001

Production Of Single-Cell Protein From Ram Horn Hydrolysate, Esabi̇ Başaran Kurbanoğlu

Turkish Journal of Biology

Candida utilis NRRL Y-900 was grown on horn hydrolysate for single-cell protein production. First, ram horns obtained from slaughterhouse in Erzurum were hydrolyzed by physical and chemical methods and crude horn hydrolysate (CHH) was obtained. The contents of protein, nitrogen, ash, some minerals, total sugars and amino acids of CHH were determined and it was seen that it has sufficient organic and inorganic materials to allow its use as a substrate source in the production of single-cell protein. The CHH was enriched by addition of yeast extract, glucose and KH_2PO_4. The effects of different CHH concentrations (1, 2, 3, 4, …


In Situ Localization Of Germin Gene Expression During Auxin Induced Callus Formation, Mahmut Çalişkan Jan 2001

In Situ Localization Of Germin Gene Expression During Auxin Induced Callus Formation, Mahmut Çalişkan

Turkish Journal of Biology

Wheat embryogenic callus was induced by treating immature wheat embryos with 2,4-D. Digoxigenin-labeled germin sense and anti-sense RNA probes were prepared by in vitro transcription. By using these probes it was revealed that there was a striking induction of germin gene expression prior to visible callus formation. Although no germin gene expression was localized on the sections of immature embryos which were not incubated in callus induction medium, following 4 hours incubation in callus induction medium, germin mRNA was localized on the sections of immature embryos. Germin gene expression more conspicuous and widespread on the sections which were incubated for …


New Photochemical And Electrochemical Methods For The Degradation Of Pesticides In Aqueous Media. Environmental Applications, J. J. Aaron, Mehmet A. Oturan Jan 2001

New Photochemical And Electrochemical Methods For The Degradation Of Pesticides In Aqueous Media. Environmental Applications, J. J. Aaron, Mehmet A. Oturan

Turkish Journal of Chemistry

The development of new electrochemical and photochemical methods for the decontamination of natural water containing significant concentrations of aromatic pesticides is described. The electrochemical method is based on the electro-Fenton process, i.e. the simultaneous reduction of O_{2} and Fe^{3+} ions. Hydroxyl (OH^{.}) radicals are electrosynthesized in aqueous solutions, followed by complete mineralization of the initial pollutants. The photochemical methods involve either a direct photodegradation reaction of pesticides by UV light, or indirect photodegradation processes including H_{2}O_{2} photolysis or photo-Fenton reagents (H_{2}O_{2}/ Fe^{3+} ). Examples of the application of these methods to chlorophenoxy acid herbicides and four aromatic pesticides (bendiocarb, pirimiphos-methyl, …


Viral Control Of The European Pine Sawfly, Neodiprion Sertifer (Geoffroy) In Turkey, Mustafa Yaman, Remzi̇ye Nalçacioğlu, Zi̇hni̇ Demi̇rbağ Jan 2001

Viral Control Of The European Pine Sawfly, Neodiprion Sertifer (Geoffroy) In Turkey, Mustafa Yaman, Remzi̇ye Nalçacioğlu, Zi̇hni̇ Demi̇rbağ

Turkish Journal of Biology

The European pine sawfly, Neodiprion sertifer (Geoffr.) (Hymenoptera: Diprionidae), is a serious pest of pine plantations and ornamentals. Chemical pesticides used to control this pest have a detrimental effect on the environment. The Neodiprion sertifer nuclear polyhedrosis virus (NsNPV) frequently causes considerable decreases in the populations but doses not harm other animals or plants. In this study, we tested five different concentrations of NsNPV against the larvae of N. sertifer and showed viral infection using Giemsa staining. When a viral concentration of 5x10^9 PIB/ml (Polyhedral Inclusion Body) was utilized, larval mortality started on the fourth day and reached 90.4% on …


Susceptibility Of Different Bean (Phaseolus Vulgaris L.) Cultivars To Agrobacterium Tumefaciens, Azi̇z Karakaya, Sebahatti̇n Özcan Jan 2001

Susceptibility Of Different Bean (Phaseolus Vulgaris L.) Cultivars To Agrobacterium Tumefaciens, Azi̇z Karakaya, Sebahatti̇n Özcan

Turkish Journal of Biology

Although several direct gene transfer techniques have been developed, Agrobacterium tumefaciens is still preferred for the transfer of foreign genes into many plant species. Perhaps the greatest weakness of A. tumefaciens is the host range limitation. Therefore, in this study, the susceptibility of different bean cultivars to oncogenic A. tumefaciens strain A281 was assessed. The cultivars 4F-2409, Karacaşehir-90, Akman-98 and Eskişehir-855 resulted in higher frequencies of tumor formation than the other cultivars tested. Tumor formation was not observed in Afyon-3, IVD-10, Göynük-98, Yunus-90 or Şehirali-90 bean cultivars. Tumor formation was observed on both the hypocotyl and epicotyl portions of the …


Ga3, Aba And Cytokinin Production By Lentinus Tigrinus And Laetiporus Sulphureus Fungi Cultured In The Medium Of Olive Oil Mill Waste, Bi̇rgül Özcan, S. Fati̇h Topcuoğlu Jan 2001

Ga3, Aba And Cytokinin Production By Lentinus Tigrinus And Laetiporus Sulphureus Fungi Cultured In The Medium Of Olive Oil Mill Waste, Bi̇rgül Özcan, S. Fati̇h Topcuoğlu

Turkish Journal of Biology

The levels of endogenous form of free, bound and total-gibberellic acid (GA_3), abscisic acid (ABA) and cytokinin (zeatin) in culture medium were determined. The changes in dry weight of the mycelium, dependent on the culture periods, was examined through the use of white-rot fungus Lentinus tigrinus and brown-rot fungus Laetiporus sulphureus which were cultured in the medium of olive oil mill waste in a static culture. Spectrophotometric techniques were used to determine the amounts of endogenous GA_3, ABA and zeatin. As a result, fungi used in this study showed that they synthesized GA_3, ABA and zeatin as a primary or …


Cover And Contents Jan 2001

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 2001

Cover And Contents

Turkish Journal of Biology

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Exploring The Concept Of A Forest Landscape Management Paradigm, Emi̇n Zeki̇ Başkent, Haci̇ Ahmet Yolasiğmaz Jan 2000

Exploring The Concept Of A Forest Landscape Management Paradigm, Emi̇n Zeki̇ Başkent, Haci̇ Ahmet Yolasiğmaz

Turkish Journal of Agriculture and Forestry

The concept of forest management planning has rapidly progressed towards a more holistic approach in the last decade. Considering the whole landscape of ecosystems is the focus of landscape management. This paper examines the evolutionary process of forest management and compares and contrasts the landscape management planning concept to its predecessor, the conventional forest resource management approach. It explains the conceptual framework, provides the principles and the improvements over the conventional management planning, and discusses different approaches towards the landscape management concept. However, the paper stresses the fact that the evolutionary process of forest management provides the basis for what …


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Studies On The Methylation Of 5-Nitro-Benzimidazoles, Mashooda Hasan, Farzana Shaheen, Uzma Yunus Jan 2000

Studies On The Methylation Of 5-Nitro-Benzimidazoles, Mashooda Hasan, Farzana Shaheen, Uzma Yunus

Turkish Journal of Chemistry

Methylation of 2H, 5-nitro- (1) and 2-ethyl, 5-nitro- (2) benzimidazoles separately with methyl iodide in acetone in the presence of potassium carbonate yielded 2H, 5/6-nitro-(3A and 3B) and 2-ethyl, 5/6-nitro- (4A and 4B) methylbenzimidazoles respectively. Methylation of 1 and 2 in dimethylformamide in place of acetone yielded not only 3A, 3B and 4A, 4B respectively, but in addition 1,3-dimethyl-5-nitro-benzimidazol-2-one (5) was also obtained in each case. The structure of the synthesized compounds was determined with the help of mass and ^1H NMR spectroscopic analysis.


Specific Determination Of Hydrogen Peroxide With A Catalase Biosensor Based On Mercury Thin Film Electrodes, F. Ni̇l Ertaş, Suna Ti̇mur, Erol Akyilmaz, Erhan Di̇nçkaya Jan 2000

Specific Determination Of Hydrogen Peroxide With A Catalase Biosensor Based On Mercury Thin Film Electrodes, F. Ni̇l Ertaş, Suna Ti̇mur, Erol Akyilmaz, Erhan Di̇nçkaya

Turkish Journal of Chemistry

A biosensor for specific determination of hydrogen peroxide was developed using catalase (EC 1.11.1.6) in combination with a mercury film electrode. Catalase was immobilized with gelatine by means of glutaraldehyde on the electrode surface. The biosensor response was monitored by following the reduction peak of dissolved oxygen at around -0.24 V. The peak current changes upon addition of hydrogen peroxide and gives a linear response in a concentration range of 1-50 x 10^{-6} M within a response time of 3 minutes.


Spectrophotometric Determination Of Selenium (Iv) Using Methdilazine Hydrochloride, Mahaveer B. Melwanki, Jaldappa Seetharamappa Jan 2000

Spectrophotometric Determination Of Selenium (Iv) Using Methdilazine Hydrochloride, Mahaveer B. Melwanki, Jaldappa Seetharamappa

Turkish Journal of Chemistry

Methdilazine hydrochloride is proposed as a selective and sensitive reagent for the spectrophotometric determination of selenium (IV). The reagent forms a red radical cation by selenimum (IV) in hydrochloric acid medium and exhibits an absorption maximum at 513 nm. Beer's law is valid over the concentration range 0.1-2.3 mg1^{-1} of selenium (IV). Sandell's sensitivity of the reaction is found to be 3.57 ng cm^{-2} and the molar extinction coefficient is 9.32 x 10^4 1 mol^{-1} cm^{-1} at 513 nm. The effects of acidity, reagent concentration, temperature and diverse ions upon the absorbance of the red species are critically assessed. The …


A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler Jan 2000

A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler

Turkish Journal of Chemistry

A series of 3-alkyl-4-(arylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 6-10,} was obtained from the reaction of the corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 1,} with the appropriate aldehydes. 3-alkyl-4-(alkylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones of type {\bfseries 11-16} were synthesized from the selective reduction of compounds {\bfseries 5-10} with NaBH$_{4}$ in diglyme or DMSO medium as a general and convenient method.


Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz Jan 2000

Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz

Turkish Journal of Chemistry

The construction and performance characteristics of ion-selective membrane electrodes for a newly found phenylpiperazine antidepressant, Nefazodone (NFN), based on its ion-pair complexes with phosphotungstate (PT), tetraphenylborate (TPB), tungstosilicate (TS) and reineckate (RN) in a poly(vinyl chloride) (PVC) matrix are described. The best ion-selective electrode for determination of NFN contains NFN-PT as the active material. This electrode exhibits a Nernstian response (62.6 ± 0.4 mV per decade) in the range 1.5 x 10$^{-5}$ to 1.0 x 10^{-2} M NFN.HCl in solutions. The selectivity of this electrode to NFN in the presence of a number of sugar molecules, cations and drugs is …


Nonspecific Esterase Patterns Of Rattus Norvegicus(Berkenhout, 1769) In Western Turkey, Reyhan Çolak, Nuri̇ Yi̇ği̇t, Ercüment Çolak, Mustafa Sözen, Şaki̇r Özkurt Jan 2000

Nonspecific Esterase Patterns Of Rattus Norvegicus(Berkenhout, 1769) In Western Turkey, Reyhan Çolak, Nuri̇ Yi̇ği̇t, Ercüment Çolak, Mustafa Sözen, Şaki̇r Özkurt

Turkish Journal of Biology

Nonspecific esterases in the muscle, heart, kidney and liver tissues of wild rats (Rattus norvegicus) were examined by horizontal starch gel electrophoresis. Zymogram bands corresponding to Es-10 and Es-4 in the muscle, heart, kidney and liver homogenates, Es-3 and Es-17 in the kidney and liver, Es-18 in the liver tissue, Es-15 in kidney and liver, Es-2 in the muscle and heart, Es-16 in the heart tissue were detected. These findings showed that nonspecific esterases are very polymorphic and tissue-specific, and are not of taxonomic importance for the populations of Rattus norvegicus.


New Floristic Records From Square B6 (Sivas/Kayseri), Erol Dönmez Jan 2000

New Floristic Records From Square B6 (Sivas/Kayseri), Erol Dönmez

Turkish Journal of Botany

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.


Breast Carcinoma Showing Neuroendocrine Differentiation Characterized With Ectopic Hormone Production (2 Case Reports), Gülay Özbi̇li̇m, Bahar Kiliçarslan, Ekmel Tezer, Ayla Büyükkeçe, Melek Üstün, Şeyda Karaveli̇, Nezi̇hi̇ Oygür Jan 2000

Breast Carcinoma Showing Neuroendocrine Differentiation Characterized With Ectopic Hormone Production (2 Case Reports), Gülay Özbi̇li̇m, Bahar Kiliçarslan, Ekmel Tezer, Ayla Büyükkeçe, Melek Üstün, Şeyda Karaveli̇, Nezi̇hi̇ Oygür

Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.


The Role Of Renin-Angiotensin System Inregulating Fibrinolytic Balance: Potentialmechanism In Prevention Of Myocardialinfarction, Mehmet Ağirbasli, Douglas E. Vaughan Jan 2000

The Role Of Renin-Angiotensin System Inregulating Fibrinolytic Balance: Potentialmechanism In Prevention Of Myocardialinfarction, Mehmet Ağirbasli, Douglas E. Vaughan

Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.


The Effects Of Sodium Selenite On The Antioxidative Defence Mechanism Of Human Hepatoma G_2 Cells, Kayahan Fişkin Jan 2000

The Effects Of Sodium Selenite On The Antioxidative Defence Mechanism Of Human Hepatoma G_2 Cells, Kayahan Fişkin

Turkish Journal of Medical Sciences

Human cells that live in biological harmony can become cancerous. As they do so, they engage in anaerobic respiration, undergo rapid cell growth and division according to nonmitotic rules, and important changes take place in their metabolism. We conducted several investigations in an effort to block or change the metabolic characteristics of cancer cells using a typical cancerous cell line. Specifically,we investigated the effects of sodium selenite (Na_2 SeO_ 3 ) on antioxidant enzyme activities and reduced glutathione levels in Hepatoma G_ 2 cells, cells that show rapid glutamine uptake and metabolism. A Hepatoma G_ 2 cell line was cultured …


Biomimetic Preparation Of Ha Powders At 37°C In Urea-And Enzyme Urease-Containing Synthetic Body Fluids, Defne Bayraktar, A. Cüneyt Taş Jan 2000

Biomimetic Preparation Of Ha Powders At 37°C In Urea-And Enzyme Urease-Containing Synthetic Body Fluids, Defne Bayraktar, A. Cüneyt Taş

Turkish Journal of Medical Sciences

An important inorganic phase of synthetic bone applications, calcium hydroxyapatite (HA, Ca_10 (PO_ 4 ) 6_(OH_2 ), was prepared as a single-phase and sub-micron bioceramic powder. Carbonated HA powders were synthesized from calcium nitrate tetrahydrate and di-ammonium hydrogen phosphate salts dissolved in synthetic body fluid (SBF) solutions, containing urea (H_2 NCONH_2 ) and enzyme urease, under the biomimetic conditions of 37°C and pH 7.4, with a novel chemical precipitation technique. These powders were also found to contain trace amounts of Na and Mg ions in them, intentionally incorporated by using SBF solutions, instead of pure water, during their synthesis. The …


Serum Antiotensin Converting Enzyme Activity In Streptozotocin-Induced Diabetic Rats, Mustafa Vakur Bor, Esra Seval Elmali, Ni̇lgün Altan Jan 2000

Serum Antiotensin Converting Enzyme Activity In Streptozotocin-Induced Diabetic Rats, Mustafa Vakur Bor, Esra Seval Elmali, Ni̇lgün Altan

Turkish Journal of Medical Sciences

No abstract provided.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Medical Sciences

No abstract provided.