Karakurt, Halil | Kotan, Recep | Dadaşoğlu, Fatih | Aslantaş, Rafet | Şahin, Fikrettin

Article | 2011 | Turkish Journal of Biology35 ( 3 ) , pp.283 - 291

Bu çalışma bitki büyümesini teşvik eden 4 bakterinin (Bacillus subtilis OSU - 142, Bacillus megaterium M - 3, Burkholderia cepacia OSU - 7 ve Pseudomonas putida BA - 8) tek başlarına veya kombinasyonlar halinde vişnenin (Prunus cerasus cv. Kütahya) vejetatif gelişimine olduğu kadar pomolojik ve kimyasal özellikleri üzerine de etkilerini değerlendirmek için yürütülmüştür. Kullanılan bütün bakteri suşlarının tek başlarına ya da kombinasyonlarının özellikle meyve tutumu ve vejetatif gelişme üzerine doğrudan; meyvelerin pomolojik ve kimyasal özellikleri üzerine dolaylı olarak olumlu yönde bir etkisinin olduğu görülmüştür. Bu yüzden bu b . . .akteri suşlarının sürdürülebilir ya da ekolojik tarım sistemlerinde meyve, sebze ve süs bitkileri yetiştiriciliğinde biyogübre olarak kullanılabileceği düşünülmektedir. Th is study was performed to determine eff ects of 4 plant growth promoting rhizobacteria (Bacillus subtilis OSU - 142, Bacillus megaterium M - 3, Burkholderia cepacia OSU – 7, and Pseudomonas putida BA - 8) alone and in combinations on fruit set of sour cherry trees (Prunus cerasus L., cv. Kütahya), and to investigate their resulting pomological and chemical characteristics as well as vegetative growth. All the tested bacterial strains alone or some of their combinations have a great potential to increase especially fruit set and plant vegetative growth, and indirectly aff ect fruit pomological and chemical characteristics. Th erefore, they may be considered as biofertilizer for fruit, vegetable, and ornamental plant production in sustainable and ecological agricultural systems Daha fazlası Daha az

Aydın, Safa | Yalvaç, Mehmet Emir | Özcan, Ferruh | Şahin, Fikrettin

Article | 2016 | Turkish Journal of Biology40 ( 4 ) , pp.747 - 754

Electroporation is a safe and efficient method to transfect human tooth germ stem cells (hTGSCs), which are mainly mesenchymal stem cells (MSCs). In this study, pluronic F68 (PF68), a nonionic and low-foaming surfactant, was used for the first time to increase the transfection efficiency in electroporation of hTGSCs. Our results revealed that when PF68 was used in the preincubation, electroporation, and recovery medium, it dramatically increased transfection efficiency. Moreover, use of PF68 did not alter the differentiation capacity of hTGSCs, whereas cells electroporated without PF68 had significantly lower expression of Oct-4, pl . . .uripotency marker gene, and alkaline phosphatase (ALP) activity upon osteogenic differentiation. We found that PF68 increases transfection efficiency in both electroporation and chemical transfection of cancer cells lines MCF-7 and HeLa. The study suggested that PF68 might be a safe and reliable chemical to use for increasing transfection efficiency during electroporation and chemical transfections Daha fazlası Daha az

Demirci, S. | Kaya, M.S. | Doğan, A. | Kalay, Ş. | Altin, N.Ö. | Yarat, A. | Şahin, Fikrettin

Article | 2015 | Turkish Journal of Biology39 ( 3 ) , pp.417 - 426

Secondary dental caries are one of the major reasons for restoration replacements. Incorporating antimicrobial properties into dental materials would limit the initiation and progression of dental caries. In the current study, dental composites having 1%, 5%, and 10% (w/w) sodium pentaborate pentahydrate were prepared and analyzed for their mechanical properties, degree of monomer conversion (DC) rate, antibacterial effects against Streptococcus mutans, and biocompatibility with human dental pulp stem cells (hDPSCs). Incorporation of boron into the composites significantly decreased flexural strength and DC in a dose-dependent manne . . .r, but the value for 1% boron-containing composite still remained within acceptable levels. Compressive strength and diametral tensile strength were not found to be different from those of controls. Although no inhibition zone was detected in an agar-well diffusion assay for any materials tested, significant bacterial growth inhibition was obtained in a direct contact test for boron-containing composites. Immunocytochemical and lineage-specific gene expression analysis revealed that composites with boron content increased the osteogenic and odontogenic capacity of hDPSCs. Boron-containing dental composites showed promising results for future clinical applications, displaying nontoxic, osteogenic, and odontogenic-inducing characteristics with remarkable antibacterial activity against S. mutans, and are hence potentially able to prevent secondary caries. © TÜBİTAK Daha fazlası Daha az

Kocabaş, Fatih | Ergin, Enes Kemal

Article | 2016 | Turkish Journal of Biology40 ( 1 ) , pp.239 - 249

Crimean-Congo hemorrhagic fever virus (CCHFV) is a deadly tick-borne virus with high mortality rates. Current antivirals lack specificity, making them susceptible to off-target effects and cytotoxicity. There is an utmost need for the identification of active compounds for anti-CCHFV therapies. Inhibition of CCHFV ovarian tumor (OTU) protease by small molecules is an exciting potential antiviral therapy. In this study, computational approaches based on residue homology, the binding coordinates of ligands, and correlation analysis with in vitro data identified the pocket of Y89-W99 as the inhibition site of CCHFV OTU protease. In sil . . .ico screening of more than 600,000 compounds against this newly discovered pocket can identify potent inhibitors of CCHFV OTU protease. This novel set of compounds exhibits a common substructure and higher binding affinities. These findings distinguish the pocket of Y89-W99 as a pharmaceutical target for the optimization and identification of CCHFV OTU protease inhibitors that could serve as lead structures for discovering therapies against CCHFV Daha fazlası Daha az

Aydoğdu, Nurullah | Taşlı, Pakize Neslihan | Şişli, Hatice Burcu | Yalvaç, Mehmet Emir | Şahin, Fikrettin

Article | 2016 | Turkish Journal of Biology40 ( 2 ) , pp.430 - 442

Stem cell-based applications have become a popular and promising approach for therapy for a number of disorders including neurodegenerative diseases, degenerative muscle diseases, and osteoporosis, as well as trauma, inflammations, burns, and injuries. Human tooth germ stem cells are an adult stem cell source; they have mesenchymal stem cell properties and show high proliferative and differentiation capacity. Melatonin has been demonstrated to regulate differentiation of human and mouse mesenchymal stem cells into various cell lineages in addition to its other functions in the body. In the current study, the effects of melatonin on . . .osteogenic, neurogenic, adipogenic, chondrogenic, myogenic, and odontogenic differentiation of human tooth germ stem cells were investigated. The results showed that melatonin increases the viability of cells. It significantly augments osteogenic, neurogenic, chondrogenic, myogenic, and odontogenic differentiation of the cells, whereas it reduces adipogenic differentiation capability. These results suggest that melatonin has a great potential to increase differentiation capacity of human tooth germ stem cells and might be useful in regenerative therapy applications involving stem cell differentiations in addition to defining potential treatments for obesity because of its suppressor effects on adipogenesis Daha fazlası Daha az

İyigündoğdu, Zeynep Ustaoğlu | Demirci, Selami | Baç, Nurcan | Şahin, Fikrettin

Article | 2014 | Turkish Journal of Biology38 ( 3 ) , pp.420 - 427

The present work involves development of stable antimicrobial materials containing silver- and zinc-ion-exchanged zeolites. Faujasite X and Linde type A zeolites were synthesized, and following ion exchange with Ag and Zn ions they were found to exhibit antimicrobial effects against bacteria (E. coli, P. aeruginosa, and S. aureus), yeast (C. albicans and C. glabrata), and fungi (A. niger and P. expansum). Zeolites-X and -A containing silver and zinc ions were then mixed with various coating materials, including paints and polypropylene, to develop antimicrobial composites. The long-term antimicrobial characteristics of zeolite-conta . . .ining composite materials were investigated by inoculating selected microorganisms onto the surface of the materials. The results indicated that the higher the zeolite concentration present in the composite, the more long-term antimicrobial activity was achieved. Silver-ion-exchanged zeolites were more effective against bacterial and candidal species, while zinc zeolites exhibited noticeable antifungal properties. Materials manufactured with metal-ion-exchanged zeolites would prevent microbial growth on surfaces, reducing cross-contamination and infection risk as well as the microbial degradation of products Daha fazlası Daha az

Gürbüz, I. | Yeşlada, E.

Article | 2008 | Turkish Journal of Biology32 ( 4 ) , pp.259 - 263

The aerial part of Equisetum telmateia Ehrh. is used against various conditions including stomachache and peptic ulcer in Turkish folk medicine. In order to prove the claimed anti-ulcerogenic potential of the plant, aqueous and methanol extracts were prepared from aerial parts of E. telmateia and investigated for their anti-ulcerogenic effect on ethanol-induced gastric ulcer model in rats. Pharmacological experiments clearly demonstrated that the oral administration of both methanol and aqueous extracts of Equisetum telmateia Ehrh. plant showed significant stomach protection (77.9% and 100% ulcer inhibition, respectively) against th . . .e applied model of ulcerogenesis (P < 0.001). Since both extracts were found significantly active, 80% ethanol was preferred for the extraction of the plant material and this crude methanolic extract was further fractionated by successive solvent extractions with chloroform and H2O saturated n-BuOH to obtain the chloroform and n-BuOH extracts as well as the remaining aqueous extract. The 80% ethanol extract and the solvent extracts were then submitted to pharmacological assay using the same in vivo experimental ulcer model. All the extracts statistically showed potent anti-ulcerogenic effect on this model (P < 0.001). However, the remaining aqueous extract was found prominent (98.2% ulcer inhibition). Consequently, folkloric utilization of E. telmateia on peptic ulcer has been confirmed in the present study by using ethanol-induced experimental ulcer model in rats. © TÜBİTAK Daha fazlası Daha az

Arasoğlu, Tülin | Derman, Serap | Mansuroğlu, Banu | Uzunoğlu, Deniz | Koçyiğit, Büşra | Gümüş, Büşra | Tuncer, Burcu

Article | 2017 | Turkish Journal of Biology41 ( 1 ) , pp.127 - 140

The use of quercetin as a bioflavonoid is becoming increasingly common in food industries even though poor water solubility, instability, absorption, and permeability have limited its application. The oil-in-water single-emulsion solvent evaporation method to synthesize highly stable and soluble quercetin-encapsulated nanoparticles (NPs), in which the reaction yield, particle size, and polydispersity of the NPs are varied greatly within the process parameters of the synthesis method, has been optimized. NPs with different initial quercetin amounts were used to determine how the quercetin amount affected nanoparticle properties and a . . .ntimicrobial efficiency. Listeria monocytogenes, Salmonella typhimurium, Escherichia coli, and Staphylococcus aureus were chosen as model bacteria due to their being foodborne pathogens. The results of antimicrobial activity evaluated by three different methods showed that the antimicrobial activity of both quercetin NPs and free quercetin was effective on gram-positive strains (L. monocytogenes and S. aureus). Additionally, it was detected that Q31 NPs have more effective antimicrobial activity than other synthesized quercetin nanoparticles depending on the amount of substance and release. Furthermore, on the basis of assessing the antibacterial effects by scanning electron microscopy, it was detected that bacteria cells lost their integrity and became pale with the release of cytoplasm and decomposed after treatment with Q31 NPs Daha fazlası Daha az

Öğütçü, Hatice | Sökmen, Atalay | Sökmen, Münevver | Polıssıou, Moschos | Serkedjıeva, Julia | Daferera, Dimitra | Güllüce, Medine

Article | 2008 | Turkish Journal of Biology32 ( 3 ) , pp.181 - 192

Bu çalışma, Salvia limbata C.A.Mey. ve Salvia sclarea L. bitkilerinin çeşitli özütleri ve uçucu yağının in vitro antimikrobiyal, antioksidan, antiviral aktivitelerinin ve uçucu yağ içeriğinin araştırılması için tasarlanmıştır. Uçucu yağ aktivitesi, insan, bitki ve gıda kaynaklı geniş bir mikroorganizma grubuna karşı test edilmiştir. 35 bakteri, 19 mantar ve maya türlerinden oluşan toplam 55 mikroorganizma disk difüzyon metodu, mikro-dilüsyon ve mikro-well dilüsyon yöntemleri kullanılarak test edilmiştir. Uçucu yağlar test edilen mantarlardan bazılarına karşı antimikrobiyal aktiviteye sahip iken bakterilerden hiçbirine karşı aktivite . . . gözlenmemiştir. Hidrodistilasyon ile elde edilen uçucu yağların kimyasal bileşenleri GC-MS ile analiz edilmiştir. Salvia türlerinin yağının temel bileşenleri spathulenol (% 29,30) ve germacrene D (% 24,72) olarak belirlenmiştir. Diğer önemli bileşenler ise sırası ile sclareoloxide (% 14,08) ve ?-caryophyllene (% 16,24) olarak belirlenmiştir. Sonuçlar bu Salvia türlerinin bitkisel yağ bileşenlerinde önemli derecede farklılıklar olduğunu göstermiştir. Antioksidan aktivite, serbest radikal giderici DPPH ve linoleik asit oksidasyonu olmak üzere iki metot kullanılarak çalışılmıştır. Kontrol olarak kullanılan sentetik antioksidan BHT (% 96 1)’e karşı, ?-karoten/linoleik asit sistem seviyeleri sırası ile % 85,1 1 ve % 76,6 1, olarak tespit edilmiştir. Antiviral aktivite çalışmalarında Salvia türlerinin MeOH özütleri önemli anti-influenza virus etkisi ve sınırlı antiherpetik etki göstermiştir. The present study evaluated the in vitro antimicrobial, antioxidant, and antiviral activities of the essential oil and various extracts of Salvia limbata C.A.Mey. and Salvia sclarea L., as well as the content of its essential oil. The activities of essential oils were tested against a wide range of human-, plant-, and food-borne microorganisms. A total of 55 microbial organisms belonging to 35 bacteria and 19 fungi and yeast species were tested using disk diffusion, micro dilution, and micro-well dilution. The essential oils were found to possess antimicrobial activity against some of the tested fungi, while no activity was observed against the bacteria. The chemical compositions of the plant hydrodistilled essential oils were analyzed by means of GC-MS. The main compounds of Salvia species oils were spathulenol (29.30%) and germacrene D (24.72%). Other important components were sclareoloxide (14.08%) and &#946;-caryophyllene (16.24%). The results showed that the compositions of the essential oils of these Salvia species varied significantly. Antioxidant activity was measured by 2 methods, namely scavenging of free radical DPPH and the inhibition of linoleic acid oxidation. In the &#946;-carotene/linoleic acid system, values were 85.1% ± 1 and 76.6% ± 1, respectively, being comparable with that of the synthetic antioxidant BHT (96% ± 1). In antiviral activity assays, the MeOH extracts from Salvia species had a significant anti-influenza virus effect and limited antiherpetic activity Daha fazlası Daha az

Gürbüz, İlhan | Demirci, Betül | Franz, Gerhard | Başer, Kemal Hüsnü Can | Yeşilada, Erdem | Demirci, Fatih

Article | 2013 | Turkish Journal of Biology37 ( 1 ) , pp.114 - 121

Aerial parts of Daphne pontica were collected from Ilgaz-Çankırı, and D. oleoides subsp. oleoides was collected from 2 different localities (Ayrancı-Karaman and Ilgaz-Çankırı) in Turkey. The samples were subjected to hydrodistillation and microdistillation. The resulting volatile samples were analyzed both by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), respectively. The main components for D. pontica were identified as hexahydrofarnesyl acetone (8.6%), carvacrol (8.5%), dihydroedulane II (4.7%), (E)-geranyl acetone (4.6%), and thymol (4.5%), while nonacosane (42.5% and 27.2%), hexadecanoic . . . acid (24.4% and 20.0%), phytol (12.3%), and carvacrol (5.0%) were identified as the main components of D. oleoides subsp. oleoides obtained by hydrodistillation. Carvacrol (12.0%), thymol (7.7%), dihydroactinidiolide (7.2%), bicyclosesquiphellandrene (5.5%), and (Z)-3-hexenal (4.1%) were the major components in D. pontica, while carvacrol (27.2% and 25.4%), nonacosane (24.6%), (Z)-3-hexenal (18.5% and 2.5%), decane (7.4%), hexahydrofarnesyl acetone (7.4% and 2.2%), hexanal (6.6% and 1.5%), heptacosane (6.1%), nonanal (5.6% and 1.9%), thymol (5.1% and 2.3%), and phytol (5.0%) were identified in the D. oleoides subsp. oleoides isolated by microdistillation, respectively. In addition, the volatile components were evaluated for their ability to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals using a bioautographic thin layer chromatography (TLC) method, and the samples showed activity comparable with that of the tested standards, vitamins C and E Daha fazlası Daha az

Gürbüz, İlhan | Yeşilada, Erdem

Article | 2008 | Turkish Journal of Biology32 ( 4 ) , pp.259 - 263

Equisetum telmateia bitkisinin topraküstü kısımları Türkiye’de halk arasında mide ağrısı ve peptik ülser dahil olmak üzere çeşitli hastalıkların tedavisinde halk ilacı olarak kullanılmaktadır. E. telmateia’nın iddia edilen antiülserojenik etkisini incelemek için toprak üstü kısımlarının sulu ve metanollü ekstreleri hazırlanmış ve sıçanlarda etanolle oluşturulan gastrik ülser modelinde incelenmiştir. Farmakolojik deneyler materyalin metanollü ve sulu ekstrelerinin her ikisinin de oral yolla uygulandığında bu ülser modeli üzerinde midede anlamlı bir koruma sağladığını (ülser önleme oranı sırasıyla %77,9 ve %100) göstermiştir (P 0,001) . . .. Her iki ekstrenin de aktif olması nedeniyle, materyalin %80 etanol ile ekstre edilmesi tercih edilmiş; ardından %80 etanol ekstresi kloroform ve suyla doyurulmuş n-bütanol ile daha ileri bir ayırıma tabi tutularak, kloroform, n-bütanol ve kalan su ekstreleri elde edilmiştir. %80 etanol ekstresi ve sıvı-sıvı ekstraksiyonla elde edilen ekstreler aynı in vivo deneysel ülser modeline uygulanmıştır. Tüm ekstreler bu model üzerinde istatistiksel olarak kuvvetli antiülserojenik etki göstermiş (P 0.001), ancak en belirgin etki kalan sulu ekstrede görülmüştür (ülser önleme oranı %98,2). Sonuç olarak bu çalışmayla E. telmateia’nın halk arasında peptik ülser üzerindeki kullanımı, sıçanlarda etanolle oluşturulan deneysel gastrik ülser modeli kullanılarak doğrulanmıştır. The aerial part of Equisetum telmateia Ehrh. is used against various conditions including stomachache and peptic ulcer in Turkish folk medicine. In order to prove the claimed anti-ulcerogenic potential of the plant, aqueous and methanol extracts were prepared from aerial parts of E. telmateia and investigated for their anti-ulcerogenic effect on ethanol-induced gastric ulcer model in rats. Pharmacological experiments clearly demonstrated that the oral administration of both methanol and aqueous extracts of Equisetum telmateia Ehrh. plant showed significant stomach protection (77.9% and 100% ulcer inhibition, respectively) against the applied model of ulcerogenesis (P < 0.001). Since both extracts were found significantly active, 80% ethanol was preferred for the extraction of the plant material and this crude methanolic extract was further fractionated by successive solvent extractions with chloroform and H2O saturated n-BuOH to obtain the chloroform and n-BuOH extracts as well as the remaining aqueous extract. The 80% ethanol extract and the solvent extracts were then submitted to pharmacological assay using the same in vivo experimental ulcer model. All the extracts statistically showed potent anti-ulcerogenic effect on this model (P < 0.001). However, the remaining aqueous extract was found prominent (98.2% ulcer inhibition). Consequently, folkloric utilization of E. telmateia on peptic ulcer has been confirmed in the present study by using ethanol-induced experimental ulcer model in rats Daha fazlası Daha az

Aydin, S. | Yalvaç, M.E. | Özcan, F. | Şahin, Fikrettin

Article | 2016 | Turkish Journal of Biology40 ( 4 ) , pp.747 - 754

Electroporation is a safe and efficient method to transfect human tooth germ stem cells (hTGSCs), which are mainly mesenchymal stem cells (MSCs). In this study, pluronic F68 (PF68), a nonionic and low-foaming surfactant, was used for the first time to increase the transfection efficiency in electroporation of hTGSCs. Our results revealed that when PF68 was used in the preincubation, electroporation, and recovery medium, it dramatically increased transfection efficiency. Moreover, use of PF68 did not alter the differentiation capacity of hTGSCs, whereas cells electroporated without PF68 had significantly lower expression of Oct-4, pl . . .uripotency marker gene, and alkaline phosphatase (ALP) activity upon osteogenic differentiation. We found that PF68 increases transfection efficiency in both electroporation and chemical transfection of cancer cells lines MCF-7 and HeLa. The study suggested that PF68 might be a safe and reliable chemical to use for increasing transfection efficiency during electroporation and chemical transfections. © TÜBİTAK Daha fazlası Daha az