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Articles 1351 - 1380 of 1681
Full-Text Articles in Biology
Antimicrobial Effects Of Verbascum Georgicum Bentham Extract, Meryem Şengül, Hati̇ce Öğütçü, Ahmet Adigüzel, Fi̇kretti̇n Şahi̇n, Ayşe Aydan Kara, İsa Karaman, Medi̇ne Güllüce
Antimicrobial Effects Of Verbascum Georgicum Bentham Extract, Meryem Şengül, Hati̇ce Öğütçü, Ahmet Adigüzel, Fi̇kretti̇n Şahi̇n, Ayşe Aydan Kara, İsa Karaman, Medi̇ne Güllüce
Turkish Journal of Biology
The methanol extract of Verbascum georgicum Bentham (Scrophulariaceae) was investigated for its in-vitro antimicrobial properties. A total of 143 microorganisms belonging to 56 bacteria and 4 fungi and a yeast species were studied using the disk-diffusion method and microdilution assays. The results indicated that the methanol extract of V. geopgicum had an inhibitory effect on the growth of all Candida albicans isolates and 17 strains in 10 different species of bacteria, namely Bacillus amyloliquefaciens, B. subtilis, B. cereus, B. pumilus, B. megaterium, B. lentimorbus, B. licheniformis, Pseudomonas putida, P. syringae and Escherichia coli, at different concentrations ranging from 37.5 to …
Effect Of Salinity On Growth Chemical Composition And Antioxidative Enzyme Activity Of Two Malting Barley (Hordeum Vulgare L.) Cultivars, Mehmet Ali̇ Demi̇ral, Mehmet Aydin, Alper Yorulmaz
Effect Of Salinity On Growth Chemical Composition And Antioxidative Enzyme Activity Of Two Malting Barley (Hordeum Vulgare L.) Cultivars, Mehmet Ali̇ Demi̇ral, Mehmet Aydin, Alper Yorulmaz
Turkish Journal of Biology
The effects of salinity on the growth, chemical composition and superoxide dismutase (SOD) and peroxidase (POX) activities of 2 malting barley (Hordeum vulgare L.) cultivars (Kaya and Scarlet) were studied. In 10-day-old seedlings, salinity stress was initiated by applying an appropriate amount of NaCl to water, and it lasted for 30 days. Salinity decreased growth of the cultivars significantly. Scarlet restricted entry of Na^+ and Cl^- into root and translocation to leaves more efficiently than did Kaya. As a whole Scarlet produced a higher amount total chlorophyll under salinity than did Kaya. POX activity of the cultivars decreased with salinity …
Characterization Of Ammonia Oxidizing Bacteria In An Activated Sludge Plant Using A Fluorescent In Situ Hybridization Method, Gülnur Coşkuner
Characterization Of Ammonia Oxidizing Bacteria In An Activated Sludge Plant Using A Fluorescent In Situ Hybridization Method, Gülnur Coşkuner
Turkish Journal of Biology
The spatial arrangement of functionally important ammonia oxidizing bacteria (AOB) in activated sludge flocs is largely unknown and activated sludge flocs are regarded as heterogeneous agglomerations of bacterial communities. This study aimed to determine both the location of AOB microcolonies within flocs and the size variation of these microcolonies based on their location. Fluorescent in situ hybridization (FISH) was used in combination with a confocal scanning laser microscope (CSLM) to achieve these goals. Grab samples taken from a full-scale plug flow wastewater treatment plant were examined with probes targeted to AOB b-Proteobacteria (Nso1225) and a genus specific probe targeted to …
Production Of Pullulan From Beet Molasses And Synthetic Medium By Aureobasidium Pullulans, Yekta Göksungur, Asli Uçan, Ulgar Güvenç
Production Of Pullulan From Beet Molasses And Synthetic Medium By Aureobasidium Pullulans, Yekta Göksungur, Asli Uçan, Ulgar Güvenç
Turkish Journal of Biology
The production of pullulan from molasses and synthetic medium by Aureobasidium pullulans P56 in batch culture was investigated. Among the pretreatments of molasses used to increase polysaccharide production, sulfuric acid + activated carbon treatment gave better results with regard to polysaccharide concentration, polysaccharide yield and sugar utilization. A maximum polysaccharide concentration of 21.4 g l^{-1} and a pullulan concentration of 16.7 g l^{-1} were obtained in synthetic medium whereas 35.0 g l^{-1} of polysaccharide and 16.9 g l^{-1} of pullulan were obtained in molasses medium containing 50 g l^{-1} of initial sugar at pH 7.5. The highest pullulan contents of …
Cellular Functions Of The 26s Proteasome, Azmi̇ Yerli̇kaya
Cellular Functions Of The 26s Proteasome, Azmi̇ Yerli̇kaya
Turkish Journal of Biology
The 26S proteasome plays a critical role in many cellular processes by degrading a wide range of both short-lived and long-lived proteins. In this review, proteasome structure and the mechanisms of substrates targeting to the 26S proteasome are described. In addition, this review focuses on the cellular functions that are affected after inhibition of the proteasome, including immune-response, cell-cycle, and transcription. The proteasome is involved in these cellular processes because it degrades numerous short-lived proteins and regulatory proteins that control these cellular functions. Even though it is known that inhibition of the 26S proteasome results in the induction of the …
An Electrophoretic Study On Esterase And Blood Serum Proteins Of The Water Vole, Arvicola Terrestris (L., 1758) (Mammalia: Rodentia), In Kırşehir Province, Ceren İyi̇gün, Reyhan Çolak
An Electrophoretic Study On Esterase And Blood Serum Proteins Of The Water Vole, Arvicola Terrestris (L., 1758) (Mammalia: Rodentia), In Kırşehir Province, Ceren İyi̇gün, Reyhan Çolak
Turkish Journal of Biology
Esterase enzymes from 30 specimens of Arvicola terrestris in 4 localities in Kırşehir province were examined using starch gel electrophoresis and blood serum proteins from 27 specimens using SDS-PAGE. It was determined that the esterase enzyme had 2 alleles (A and B), which were coded by 1 locus. A and B allele frequencies were 0.362 and 0.638, respectively. The heterozygosity level was 0.5. It was determined that there were variations in the globulin, prealbumin and postalbumin regions, while the albumin region was monomorphic. There were 6-13 bands in the globulin region, 1-2 bands in the postalbumin zone and 2-4 bands …
The Effect Of Sex On Ischemia - Reperfusion Induced Arrhythmias And The Role Of Atp - Dependent Potassium Channel Blockage, Ersöz Gonca, Eylem Suveren Ti̇ryaki̇, Ömer Bozdoğan
The Effect Of Sex On Ischemia - Reperfusion Induced Arrhythmias And The Role Of Atp - Dependent Potassium Channel Blockage, Ersöz Gonca, Eylem Suveren Ti̇ryaki̇, Ömer Bozdoğan
Turkish Journal of Biology
The presence of more ATP-dependent potassium channels in females has been thought to play an important role in protection against myocardial ischemia. In this study, we investigated whether there is a difference in the severity of ischemia and reperfusion induced arrhythmias due to sex and, if there is, what the role of ATP-dependent potassium channel in this difference is. The left anterior descending coronary artery in rats was ligated and arrhythmias were recorded in ECG during 6 min. of ischemia and reperfusion. The duration of arrhythmias was shorter in females than in corresponding males. Glibenclamide was effective in decreasing the …
Isolation And Characterization Of Aerobic Denitrifiers From Agricultural Soil, Ebru Çelen, Mehmet Aki̇f Kiliç
Isolation And Characterization Of Aerobic Denitrifiers From Agricultural Soil, Ebru Çelen, Mehmet Aki̇f Kiliç
Turkish Journal of Biology
Denitrification is generally considered an anaerobic process. However, in recent years it has been shown that bacteria can also reduce nitrate to nitrite under aerobic conditions. The characterization of biologically available nitrogen forms and their biological cycling mechanisms is important for ecological and agricultural implications. In this study, aerobic nitrate reducers were isolated from greenhouse soil. Using a nitrate reduction assay, it was found that 39 out of 60 isolates can reduce nitrate to nitrite under aerobic conditions. Five of those 39 isolates were selected for further characterization of their aerobic nitrate reduction activity. Four of those 5 isolates were …
Effects Of Some Pesticides On Spore Germination And Larvicidal Activity Of Bacillus Thuringiensis Var. Israelensis And Bacillus Sphaericus 2362 Strain, İsmet Berber, Cumhur Çökmüş, Ekrem Atalan
Effects Of Some Pesticides On Spore Germination And Larvicidal Activity Of Bacillus Thuringiensis Var. Israelensis And Bacillus Sphaericus 2362 Strain, İsmet Berber, Cumhur Çökmüş, Ekrem Atalan
Turkish Journal of Biology
The effects of 9 commercial pesticides used commonly in agriculture on spore germination and larvicidal activity of the mosquito pathogenic B. thuringiensis var. israelensis and B. sphaericus 2362 strain were examined. Six of the pesticides was had an inverse impact on spore germination and growth of the test strains. It was determined that the pesticides with the most adverse effect were copper sulfate, methiocarb, and dalapon on spore germination of the microorganisms. Higher concentrations or MIC values of the pesticides reduced the heat-resistant spore numbers of both bioinsecticides, suppressing spore germination. These results indicated that the spores of the bacteria …
Evaluation Of Toxicity Of Tannery Effluent On Plankton Community Structure: A Multispecies Microcosm Study Ii, Yalavarthi Naga Koteswari, Ravichandran Ramanibai
Evaluation Of Toxicity Of Tannery Effluent On Plankton Community Structure: A Multispecies Microcosm Study Ii, Yalavarthi Naga Koteswari, Ravichandran Ramanibai
Turkish Journal of Biology
Laboratory experiments were conducted to evaluate the dose-dependent response of tannery effluents on plankton community structure using polyurethane foam (PF) as artificial substrate. Naturally derived planktonic communities on PF provided colonists for the development of new communities under stress conditions in the laboratory. Predictions of colonization rate, taxonomic richness and relative abundance in a series of microcosms dosed with a gradient of tannery effluent from 20% to 35% concentration were assessed after the initial dosage study (1% to 15%). Changes in taxonomic composition occur at high levels of stress. End points responding at increasing levels of stress are declines in …
The Mechanism Of Inhibition Of Human Erythrocyte Catalase By Azide, Yasemi̇n Aksoy, Mevhi̇be Balk, Hamdi̇ Öğüş, Nazmi̇ Özer
The Mechanism Of Inhibition Of Human Erythrocyte Catalase By Azide, Yasemi̇n Aksoy, Mevhi̇be Balk, Hamdi̇ Öğüş, Nazmi̇ Özer
Turkish Journal of Biology
In order to elucidate the kinetic mechanism of human erythrocyte catalase a well-known substrate, H_2O_2 and inhibitor azide were used. The catalase-mediated conversion of H_2O_2 to H_2O and O_2, in the presence and absence of azide, was studied in 50 mM phosphate buffer pH 7.0 at 37 ºC under conditions where the peroxidation side reaction (RH_2 + H_2O_2 R + 2H_2O) is negligible ([H_2O_2] =< 25 mM; assay time, 10 s). The kinetics conformed to the Michaelis-Menten model. Lineweaver-Burk plots for H_2O_2 at different fixed concentrations of azide were linear and intersected on the abscissa indicating a noncompetitive or irreversible type of inhibition. To identify the inhibition type Vm vs. [E] plots were constructed at different [N_3-]. The plots were linear and converged at the origin, indicating that N_3- is a noncompetitive inhibitor. Using a non-linear curve-fitting program, the kinetic parameters were calculated. The K_m value for H_2O_2, and the K_i value for azide were found to be 10.97 ± 1.46 mM and 1.107 ± 0.093 µM, respectively.
A Morphological Study Of The Venom Apparatus Of The Spider Allopecosa Fabilis (Araneae, Lycosidae), Külti̇ği̇n Çavuşoğlu, Meltem Maraş, Abdullah Bayram
A Morphological Study Of The Venom Apparatus Of The Spider Allopecosa Fabilis (Araneae, Lycosidae), Külti̇ği̇n Çavuşoğlu, Meltem Maraş, Abdullah Bayram
Turkish Journal of Biology
The morphological structure of the venom apparatus of Allopecosa fabrilis was studied using scanning electron microscopy (SEM). The venom apparatus is situated in the prosoma and is composed of a pair of chelicerae and venom glands. Each chelicera consists of 2 parts, a stout basal part covered by hair, and a movable fang. A venom pore is situated on the subterminal part of the fang. Just below the fang, there is a cheliceral groove next to the teeth. Each side of the groove is covered with cuticular teeth. The venom glands are large and roughly cylindrical. Each gland is surrounded …
Influence Of Arbuscular Mycorrhiza On Some Physiological Growth Parameters Of Pepper, Semra Demi̇r
Influence Of Arbuscular Mycorrhiza On Some Physiological Growth Parameters Of Pepper, Semra Demi̇r
Turkish Journal of Biology
Arbuscular Mycorrhiza (AM) is a symbiotic association between plant roots and certain soil fungi. Mycorrhiza establishment is known to modify several aspects of plant physiology such as mineral nutrient composition, hormonal balance, and C allocation patterns. In this study, the effect of the Arbuscular Mycorrhizal fungus Glomus intraradices Schenck & Smith on the physiological growth parameters of pepper (Capsicum annuum L. cv Cetinel-150) plants was investigated. To explain the physiological growth of these plants, some physiological growth parameters were determined in the shoots and leaves of mycorrhizal (M) and nonmycorrhizal (NM) plants such as the P and dry matter (d.m.) …
Genetic Analysis Of Bifunctional Genes From Rumen Bacterium, Emi̇n Özköse, İsmai̇l Akyol, Ercan Efe, M. Sai̇t Eki̇nci̇
Genetic Analysis Of Bifunctional Genes From Rumen Bacterium, Emi̇n Özköse, İsmai̇l Akyol, Ercan Efe, M. Sai̇t Eki̇nci̇
Turkish Journal of Biology
Deletion of domain B of the xynD gene was performed and the nucleotide sequence of this domain was compared with other enzyme sequences to reveal its function. Ruminococcus flavefaciens DNA fragment encodes xylanase and \beta-(1,3-1,4)-glucanase (xynD) activities with 3 domains (A, B, C). The amino-terminal domain (A) is related to family G xylanase while the carboxy-terminal domain (C) is related to family 16 \beta-(1,3-1,4)-glucanase. These 2 domains are connected by a region (B) of unknown function. Deletion of domain B leads to increased thermosensitivity of the enzyme and also in a 2-3-fold increase in \beta-(1,3-1,4)-glucanase activity. A survey of the …
Antibacterial Activities Of Some Plant Extracts Utilized In Popular Medicine In Palestine, Bassam Abu-Shanab, Ghaleb Mohammad Adwan, Dahood Abu-Safiya, Naser Jarrar, Kamel Adwan
Antibacterial Activities Of Some Plant Extracts Utilized In Popular Medicine In Palestine, Bassam Abu-Shanab, Ghaleb Mohammad Adwan, Dahood Abu-Safiya, Naser Jarrar, Kamel Adwan
Turkish Journal of Biology
The antibacterial activities of hot water, methanol and ethanol extracts of 5 plant extracts utilized in Palestine in popular medicine were studied. The dried extracts of Syzyium aromaticum (Myrtaceae) (seed), Cinnamomum cassia (Lauraceae) (cassia bark, Chinese cinnamon) (bark), Salvia officinalis (Lamiaceaea) (leaf), Thymus vulgaris (Lamiaceaea) (leaf) and Rosmarinus officinalis (Labiatae) (leaf) were tested in vitro against 4 bacterial species by disk diffusion and micro-dilution. The patterns of inhibition varied with the plant extract, the solvent used for extraction, and the organism tested. Methicillin-resistant Staphylococcus aureus (MRSA) and Bacillus subtilis ATCC 6633 were the most inhibited microorganisms. S. aromaticum extract was …
In Vitro Antifungal Activity Of Strains Of Trichoderma Harzianum, Çi̇ğdem Küçük, Meri̇h Kivanç
In Vitro Antifungal Activity Of Strains Of Trichoderma Harzianum, Çi̇ğdem Küçük, Meri̇h Kivanç
Turkish Journal of Biology
Interactions between Trichoderma harzianum strains and some soilborne plant pathogens (Gaeumannomyces graminis var. tritici, Fusarium culmorum and F. moniliforme) were studied on PDA medium. All T. harzianum strains tested produced a metabolite that inhibited growth of plant pathogenic fungi on PDA medium. When grown in liquid cultures containing laminarin, chitin or fungal cell walls as sole carbon sources, 2 strains of T. harzianum produced 1,3-\beta-glucanase and chitinase in the medium. Higher levels of these enzymes were induced by T. harzianum T15.
The Use Of Ram Horn Hydrolysate As A Supplement For Glycerol Production By Yeast, Esabi̇ Başaran Kurbanoğlu, Namudar İzzet Kurbanoğlu
The Use Of Ram Horn Hydrolysate As A Supplement For Glycerol Production By Yeast, Esabi̇ Başaran Kurbanoğlu, Namudar İzzet Kurbanoğlu
Turkish Journal of Biology
This study describes the interesting potential of ram horns to be used as a supplement for glycerol production in batch fermentation. The use of ram horn hydrolysate (RHH) as a supplement for glycerol production was investigated using baker’s yeast, Saccharomyces cerevisiae. For this purpose, RHH was first produced. The production and chemical composition of the RHH was as described in our previous study. The effects of different concentrations (1 to 10% v/v) of RHH on the production of glycerol were investigated, and 8% RHH was found to be optimal. The content of glycerol in the culture broth containing RHH (6.3 …
First Record Of A Npv Isolated From Spodoptera Littoralis (Boisd.) (Lepidoptera: Noctuidae) In Turkey And Its Molecular Identification According To The Partial Lef-8 Gene, Umut Toprak, M. Oktay Gürkan
First Record Of A Npv Isolated From Spodoptera Littoralis (Boisd.) (Lepidoptera: Noctuidae) In Turkey And Its Molecular Identification According To The Partial Lef-8 Gene, Umut Toprak, M. Oktay Gürkan
Turkish Journal of Biology
Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) is an important pest in Turkey and causes extensive economic losses in many cultivated crops. The viruses within the family Baculoviridae are specific pathogens of insects. The nucleopolyhedroviruses (NPVs), 1 of the 2 genera of this family, have been isolated from many insect orders, primarily from the lepidopterans. In our study, a local NPV was isolated from the larvae of Spodoptera littoralis fed in the cotton fields in southern Turkey (Mersin). For the molecular identification of the virus, polyhedra (occlusion bodies [OBs]) were isolated from insects and total DNA extraction was performed using a commercial …
Species Composition And Diversity Of Epipelic Algae In Çatal Lake (Şebinkarahisar-Giresun, Turkey), Bülent Şahi̇n
Species Composition And Diversity Of Epipelic Algae In Çatal Lake (Şebinkarahisar-Giresun, Turkey), Bülent Şahi̇n
Turkish Journal of Biology
The epipelic algae of Çatal Lake were studied between June and October 2002. Fifty-three taxa (39 belonging to Bacillariophyta, 8 to Chlorophyta, 5 to Cyanophyta and 1 to Euglenophyta) were determined. Based on the epipelic algal composition, Çatal Lake can be characterized as eutrophic.
Electrofusion Of Saccharomyces Cerevisiae Auxotrophic Mutants Of Identical Mating Type Using A Laboratory-Made System, Gökhan Coral, Ömer Çolak, M. Ni̇sa Ünaldi, Burhan Arikan
Electrofusion Of Saccharomyces Cerevisiae Auxotrophic Mutants Of Identical Mating Type Using A Laboratory-Made System, Gökhan Coral, Ömer Çolak, M. Ni̇sa Ünaldi, Burhan Arikan
Turkish Journal of Biology
Yeast protoplasts from haploid auxotroph strains DC6 (MAT\alpha) and FY73 (MAT\alpha) were exposed to an inhomogeneous alternating field (AC 200 V/cm). Due to the dielectrophoretic aggregation two or more cells with close membrane contact were formed between the two electrodes. The effects of different DC pulses were investigated to determine critical fusogenic pulse strength. In the results, the maximum fusant cells were obtained only when 8 kV field strengths were applied. These findings showed that the optimum fusogenic pulse strength for yeast protoplasts is 8 kV/cm under our experimental conditions. After fusion, the DNA contents of both hybrid and individual …
Extremely Halophilic Bacterial Communities In Şereflikoçhisar Salt Lake In Turkey, Meral Bi̇rbi̇r, Cenk Sesal
Extremely Halophilic Bacterial Communities In Şereflikoçhisar Salt Lake In Turkey, Meral Bi̇rbi̇r, Cenk Sesal
Turkish Journal of Biology
Şereflikoçhisar Lake is the largest salt lake in central Turkey. This lake is a major source of solar salt for food, hide and other industries locally. Due to the economic importance of salt obtained from this lake, a microbial survey has been conducted. Six salt and three brine samples were obtained from the lake for physico-chemical and microbiological analyses. Physico-chemical analysis showed that the salts and brines contain sufficient ions and hardness to support extremely halophilic bacteria. The salt collected from the lake contained 10^4-10^6 colony-forming units of extremely halophilic bacteria per gram and brine taken from the lake contained …
Biosorption Of Copper Ions By Caustic Treated Waste Baker's Yeast Biomass, Yekta Göksungur, Si̇bel Üren, Ulgar Güvenç
Biosorption Of Copper Ions By Caustic Treated Waste Baker's Yeast Biomass, Yekta Göksungur, Si̇bel Üren, Ulgar Güvenç
Turkish Journal of Biology
Waste baker's yeast (Saccharomyces cerevisiae) was used as a biosorbent for Cu^{+2} biosorption. The yeast cells were treated with caustic soda, ethanol and heat to increase their biosorption capacity. Among the treatment methods used, the highest copper uptake (21.1 mg g^{-1}) was obtained with the caustic treatment of baker's yeast. The effect of initial copper concentration and pH on biosorption for caustic treated yeast was studied. The highest Cu^{+2} uptake (120.7 mg g^{-1}) was obtained at pH 4.0, for 198.2 mg I^{-1} initial copper ion concentration. The Langmuir model and Freundlich equation were applied to the experimental data and the …
Acid Adaptation Protects Salmonella Typhimurium From Environmental Stresses, Hali̇l Tosun, Şahi̇ka Aktuğ Gönül
Acid Adaptation Protects Salmonella Typhimurium From Environmental Stresses, Hali̇l Tosun, Şahi̇ka Aktuğ Gönül
Turkish Journal of Biology
Salmonella typhimurium can encounter a wide variety of environments during its life cycle. S. typhimurium can experience and survive dramatic acid stress. However, in vitro the organism is very sensitive to acid. S. typhimurium was adapted to acid by exposure to HCl at pH 5.8 ± 0.1 for one growth cycle. Acid-adapted cells were much better protected from acid death than control cells. The relationship between acid adaptation of S. typhimurium and tolerance to other environmental stresses was also examined. Acid-adapted cells were found to have increased tolerance to various stresses including heat, salt and organic acids. No cross-protection was …
Determination Of Poly-\Beta-Hydroxybutyrate (Phb) Production By Some Mesophilic And Thermophilic Lactic Acid Bacteria, Zehra Nur Yüksekdağ, Yavuz Beyatli, Belma Aslim
Determination Of Poly-\Beta-Hydroxybutyrate (Phb) Production By Some Mesophilic And Thermophilic Lactic Acid Bacteria, Zehra Nur Yüksekdağ, Yavuz Beyatli, Belma Aslim
Turkish Journal of Biology
Accumulated poly-\beta-hydroxybutyrate (PHB) was determined in lactic acid bacteria belonging to the genera Lactobacillus, Lactococcus and Streptococcus. Lactobacilli were grown in MRS broth and the others were grown in Elliker broth medium. Cell biomass was obtained by centrifugation. The cell walls were lysed with sodium hypochlorite. Poly-\beta-hydroxybutyrate was extracted using chloroform in a Soxhlet system. Then it was converted to crotonic acid using sulfuric acid and the amount of crotonic acid was measured spectrophotometrically. The yield of poly-\beta-hydroxybutyrate % of cell dry weight of Lactobacillus species was 0.52-25.55%. The values for Lactococcus and Streptococcus species were 0.61-14.81 and 1.20-13.69%, respectively. …
Cytogenetic Effects Of Copper Chloride On The Root Tip Cells Of Helianthus Annuus L., Hüseyi̇n İnceer, Sema Ayaz, Osman Beyazoğlu, Emi̇ne Şentürk
Cytogenetic Effects Of Copper Chloride On The Root Tip Cells Of Helianthus Annuus L., Hüseyi̇n İnceer, Sema Ayaz, Osman Beyazoğlu, Emi̇ne Şentürk
Turkish Journal of Biology
The cytogenetic effects of copper chloride on root tip cells of Helianthus annuus were investigated. Seeds were treated with 10, 25, 50 and 100 mg/L (ppm) of copper chloride for 24 h. It was found that copper chloride has a marked mitodepressive action on mitosis. Mitotic abnormalities were increased and the mitotic index was decreased depending on the concentration of the copper chloride applied.
Protein And Dna In Systematic Biology, Selma Gülbi̇tti̇ Onarici, Si̇bel Sümer
Protein And Dna In Systematic Biology, Selma Gülbi̇tti̇ Onarici, Si̇bel Sümer
Turkish Journal of Biology
Since the 1960s, biological macromolecules have occupied an increasingly important role in evolutionary and systematic studies. These biological macromolecules, used as sources of molecular characteristics, are proteins and various types of DNA such as a nuclear genome, nuclear ribosomal DNA, mitochondrial genome, and chloroplast genome. Electrophoresis and immunological techniques are used for generating systematic data from proteins. Generally, electrophoretic methods focus on two general forms of protein data, isozymes and allozymes, while the basis of immunological studies is antigen-antibody reactions. Basic methodologies for using DNA for systematic purposes include DNA-DNA hybridizations, restriction enzyme analysis, sequencing, cloning, PCR and PCR-based fingerprinting …
Reproductive Response Of Adult Siberian Hamsters To One-Hour Melatonin Infusions, Bülent Gündüz, Milton H. Stetson
Reproductive Response Of Adult Siberian Hamsters To One-Hour Melatonin Infusions, Bülent Gündüz, Milton H. Stetson
Turkish Journal of Biology
The pineal hormone melatonin is known to play an important role in mediating photoperiodic messages to the reproductive system in seasonal breeding animals. In this study, we investigated whether a 1 h subcutaneous infusion of 50 ng of melatonin at 2000-2100 hours, effective in causing inhibition of testicular development in the juvenile Siberian hamsters (Phodopus sungorus), would cause testicular regression in adults of this species housed on a long photoperiod (LD16:8). Pinealectomized adult hamsters received programmed subcutaneous infusions of 50 or 500 ng of melatonin or vehicle (0.12 ml) at 2000-2100 hours each day for 8 weeks. We found that …
Neuroepithelial Endocrine Cells In The Lung Of Rana Ridibunda: An Immunohistochemical Study, Füsun Öztay, Ayşe Tabakoğlu Oğuz
Neuroepithelial Endocrine Cells In The Lung Of Rana Ridibunda: An Immunohistochemical Study, Füsun Öztay, Ayşe Tabakoğlu Oğuz
Turkish Journal of Biology
In this study, neuroepithelial endocrine cells were for the first time identified in the lung of Rana ridibunda. The presence of these cells was investigated using endocrine markers by the immunohistochemical method at the light microscopic level. Immunoreactive - cells containing serotonin, calcitonin, met-enkephalin and leu-enkephalin were observed alone or in clusters within the respiratory epithelium. In general, clustered - cells containing serotonin were detected among the ciliated cells and goblet cells of the pseudostratified epithelium on apical dilation of the primary septa where the inhaled - air is first met. Among pneumocytes, single and clustered neuroepithelial endocrine cells display …
Phospholipid And Triacylglycerol Fatty Acid Compositions From Various Development Stages Of Melanogryllus Desertus Pall. (Orthoptera: Gryllidae), Kadri̇ Bozkuş
Turkish Journal of Biology
Phospholipid and triacylglycerol fatty acid compositions from eggs; seventh, eighth and last nymphal stages; and 1, 20- and 40-day-old adult females of the black cricket, Melanogryllus desertus, grown in stock-culture medium under laboratory conditions were analyzed by gas chromatographic methods. A large amount of the fatty acid components at all the development stages of the insects analyzed comprised oleic, linoleic, palmitic and stearic acids. However, palmitoleic, myristic and linolenic acids were also found, at lower levels. There were fluctuations in fatty acid levels at different development stages, such as nymphs and adults. Oleic acid was lower in 1-day-old and older …
Investigation Of The Antimicrobial Activity Of Some Streptomyces Isolates, Nuretti̇n Şahi̇n, Aysel Uğur
Investigation Of The Antimicrobial Activity Of Some Streptomyces Isolates, Nuretti̇n Şahi̇n, Aysel Uğur
Turkish Journal of Biology
Seventy-four different Streptomyces isolates were obtained from the soils of Muğla province. Antimicrobial activity was determined in 45.9% of the isolates. Fifteen isolates showed strong activity against coagulase-negative Staphylococcus (CoNS). These isolates were extensively studied for their in vitro antimicrobial activity against Gram-positive and Gram-negative bacteria and yeasts. The results indicated that five isolates were highly active against CoNS and yeast with an inhibition zone at ? 20 mm. Three of these isolates were identified as Streptomyces antibioticus (MU106, MU107) and S. rimosus (MU114). The UV spectra of the culture extracts for the active isolates showed absorbance peaks ranging between …