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Öğe An inclusive physicochemical comparison of natural and synthetic chitin films(Elsevier, 2018) Kaya, Murat; Salaberria, Asier M.; Mujtaba, Muhammad; Labidi, Jalel; Baran, Talat; Mulercikas, Povilas; Duman, FatihNatural and synthetic chitin films, obtained from the same source were produced and their physicochemical properties were examined comparatively. Firstly, natural chitin film was obtained from elytra of an insect (Oryctes nasicornis L) and purity of the obtained chitin film (degree of acetylation: 79 +/- 2%) was demonstrated by solid state C-13 nuclear magnetic resonance (C-13 NMR). Then, the synthetic film was produced by dissolving of natural chitin film in LiCl-DMAc. The obtained natural and synthetic films were characterized by AFM, TGA, DSC, FTIR, mechanical properties, light transmission and contact angle. The analyses result demonstrated that natural chitin film lost very important properties such as high thermal stability, transparency, nanofibrous nature, tensile strength, Young's modulus and hydrophobicity after transforming the synthetic film. (C) 2017 Elsevier B.V. All rights reserved.Öğe Characterisation of ?-chitin extracted from a lichenised fungus species Xanthoria parietina(Taylor & Francis, 2015) Kaya, Murat; Halıcı, Mehmet Gökhan; Duman, Fatih; Erdoğan, Sevil; Baran, TalatLichens are symbiotic associations formed mainly by ascomycete fungi and green algae or cyanobacteria. The presence of chitin in the fungal cell wall has been revealed by previous studies. Considering the presence of fungi in the lichens, this work determines the presence of chitin in a cosmopolitan lichen species Xanthoria parietina. In this study, chitin was derived from a lichen species for the first time and its physicochemical properties were determined by Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy and elemental analysis. The dry weight chitin content of X. parietina was 4.23%, and this chitin was in the -form. The crystalline index value of the lichen chitin was calculated as 70.1%. The chitin from X. parietina had a smooth surface.Öğe Crayfish chitosan for microencapsulation of coriander (Coriandrum sativum L.) essential oil(Elsevier Science, 2016) Duman, Fatih; Kaya, MuratIn this study, chitosan, which was obtained from the waste shells of crayfish (Astacus leptodactylus), was used for the encapsulation of the essential oil isolated from coriander (Coriandrum sativum L.) via the spray drying method. The obtained capsules were characterized using SEM, FT-IR, TGA and XRD. The size of the microcapsules was between 400 nm - 7 mu m. It was determined that the swelling characteristic of the capsules was pH sensitive. The release showed bi-phasic characteristics and the maximum degree was reached after 72 h. Antimicrobial activity studies showed that pure chitosan more effective than the capsule. The antioxidant activity was recorded concentration-dependent. In contrast the antimicrobial activity, antioxidant activity of the capsule was found much higher than the oil and the pure chitosan. Consequently, it was determined that this product could be used in the food and pharmaceutical industries as a natural antioxidant and antimicrobial agent.Öğe Encapsulation of flurbiprofen by chitosan using a spray-drying method with in vitro drug releasing and molecular docking(Türk Ezcacılar Birliği, 2017) Akyüz, Lalehan; Duman, Fatih; Kaya, MuratObjectives: This study aimed to prepare chitosan-flurbiprofen micro-nano spheres as environmentally friendly for drug releasing by spray-drying method without any cross-linking agent. It was also aimed to reveal the favorable binding geometries of chitosan and flurbiprofen using molecular modeling. Materials and Methods: In this study, flurbiprofen was encapsulated with chitosan using spray-drying technique. The used chitosan, flurbiprofen and obtained spheres were characterized via fourier transmission infrared spectrometer (FT-IR), thermogravimetric analysis (TGA), X-ray diffractometer and scanning electron microscopy (SEM). Drug entrapment efficiency was carried out for determination of the drug amount in the micro-nano spheres. In vitro release studies of CS-FP spheres were also examined in the simulated biological fluid at pH 7.4. Encapsulation process of flurbiprofen was combined with the docking studies to investigate the possible binding sites of the chitosan. Results: FT-IR results confirmed that H-bonding system was formed between chitosan and drug. CS-FP spheres with spherical shape were observed by SEM. TGA analysis results showed that thermal stabilities of flurbiprofen and chitosan were decreased after the encapsulation process. The spheres were used for in vitro releasing studies in simulated biological fluids. All these analysis results clearly showed that encapsulation was successfully carried out with 73.28% efficiency. Molecular modeling studies showed that CS-FP stable complexes was formed through a hydrogen bonding system between OH group of the drug molecule and chitosan hydroxyl (OH) group with a binding energy of -3.90 kcal/mol. Our computational results supported to spectroscopic results obtained by FTIR. Conclusion: This study proved that micro-nano spheres can be prepared without using cross-linking agent by spray-drying method. The results of the drug releasing studies showed that release of encapsulated flurbiprofen was completed within 48h. The results of docking analysis can be suggested for the design of new drug carrier systems with chitosan.Öğe Habitat selection, diversity and estimating the species richness of rotifers in two ponds located in Central Anatolia(2010) Kaya, Murat; Duman, Fatih; Altındağ, AhmetSample collections from aquatic ecosystems in many studies are limited to few habitats. This study is carried out to determine habitat selection, diversity and estimating the species richness of rotifers in samples collected from diverse habitats such as benthic, phytoplanktons, macrophytes, plankton, submerged moss and Gammarus sp. in two ponds located in Central Anatolia. A total of 68 species were recorded from 32 samples (20 from Soysalli pond and 12 from Ovaciftlik pond). Overall species richness (gamma diversity) was observed as 52 and estimated species richness was 64 for Soysalli pond. Overall species richness was observed as 42 and estimated species richness is 51 for Ovaciftlik pond. Richness for each sample (alpha diversity) was 3.9 for Soysalli pond while an alpha diversity of 5.5 was recorded for Ovaciftlik pond. All recorded species in this study are widely distributed worldwide however 3 of them: Dissotrocha hertzogi, Macrotrochela concinca and Ptygurafurcillata are new records for Turkey. © Medwell Journals, 2010.Öğe Karataş gölü'nün zooplankton faunası ve ağır birikiminin mevsimsel olarak belirlenmesi ve gölden kültüre alınan daphnia magna'nın biyoremediasyon kapasitesinin lemna minor ile kıyaslanması(TÜBİTAK, 2012) Kaya, Murat; Duman, Fatih; Üçüncü, Esra; Tunca, EvrenBu çalışmada; 48h’lik süreçte, Lemna minor, Daphnia magna ve L.minor+D.magna test grupları kullanılarak, alüminyum, demir, baryum ve karışımlarının biyoremediasyonu çalışılmıştır. D.magna Karataş Gölü’nden(Burdur) elde edilmiş, ayrıca gölün mevsimsel olarak zooplankton faunası ve ağır metal değişimi belirlenmiştir. CCA(Canonical correspondence analysis) analiziyle, ağır metaller ve fizikokimyasal su parametreleri ile zooplankton türleri arasındaki dağılım tespit edilmiştir. Göl suyunda ve planktondaki birikim sırasıyla Fe>Mn>Ni>Co>Pb>Cd şeklinde bulunmuştur. Plankton ve su örneklerinin korelasyon analizleri beraber değerlendirilmiş ve Fe,Mn,Co ve Ni açısından korelasyon görülen metaller ve korelasyonun yönü ve şiddetinin son derece benzer olduğu tespit edilmiştir. Kümeleme(CA) analizi sonuçlarının değerlendirilmesindeyse hem suda hem de plankton örneklerinde Mn’nin en yakın olduğu elementin Co olduğu, Fe’nin en yakın olduğu elementin Ni olduğu ve Cd’nin en yakın olduğu elementin Ni olduğu saptanmıştır. Sedimentteki ağır metal konsantrasyonları mevsimler arasında neredeyse hiç değişim göstermemiştir. Mann Whitney U Testine göre su ve plankton örneklerinde ise mevsimler arasında ağır metal birikimleri açısından ciddi değişimler görülmüştür. L.minor+D.magna test grubunun sadece Daphnia ya da sadece Lemna içeren kültüre göre daha fazla uzaklaştırma yaptığı bir karışım bulunamamıştır. Genel olarak uzaklaştırmada lemna’nın daha başarılı olmasına karşın Al/Ba ve Ba/Fe karışımlarındaki Ba, daphnia tarafından lemnaya göre daha fazla uzaklaştırılmıştır. Sudan en çok temizlenen metal Ba olurken, 24 saatlik uzaklaştırma miktarları ile 48 saatlik uzaklaştırma miktarları arasında istatistiki bir fark görülmemiştir.Öğe Resting eggs as new biosorbent for preconcentration of trace elements in various samples prior to their determination by FAAS(Humana Press, 2014) Saçmacı, Şerife; Yılmaz, Yakup; Kartal, Şenol; Kaya, Murat; Duman, FatihIn this study, the resting eggs of aquatic creatures living in freshwater (Daphnia, Cladocera, Crustacean) ecosystems were used as a novel biosorbent extractant for synchronous preconcentration of trace Cd(II), Co(II), Cu(II), Mn(II), and Ni(II) previous to measurement by flame atomic absorpiton spectrometry (FAAS). Using column procedures, optimization studies were conducted to realize the effective adsorption of the analyte ions such as the solution pH, amount of the biosorbent, volume of the sample, interfering ions, etc. A high preconcentration factor of 67 and low relative standard deflection of a parts per thousand currency sign4.1 % (n = 8) were obtained. The invention constrains based on the 3 s/b criterion were 2.4 for Cd(II), 41.4 for Co(II), 4.2 for Cu(II), 3.0 for Mn(II), and 9.6 mu g L-1 for Ni(II). The accuracy of the method was verified by analysis of a certified standard reference material. The used procedure was applied to the definition of the analytes in diverse environmental samples with convincing results. Consequently, the resting eggs of Daphnia can be used as a biosorbent for preconcentration and biosorption studies.Öğe The quick extraction of chitin from an epizoic crustacean species (Chelonibia patula)(TAYLOR & FRANCIS, 2014) Kaya, Murat; Karaarslan, Muhsin; Baran, Talat; Can, Esra; Ekemen, Gülçin; Bitim, Betül; Duman, FatihChitin was isolated from the shells of Chelonibia patula (barnacle, Crustacea), which lives on blue crab epizoically, following a 10-min demineralisation process through HCl and a 20-min deproteinisation process through NaOH. Due to the low-crystalline structure, and mineral-rich and low-protein content of the shells, chitin isolation was convenient. It was observed that the shell structure of C. patula contains 3.11% chitin per its dry weight. Following characterisation of the isolated chitin by using Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffractometry, elemental analysis and scanning electron microscopy, it was determined that there was close similarity with the a-chitin isolated from crabs, shrimps and insects in various studies. It was observed that chitin was composed of nanofibres with a width of 10-20 nm. It was concluded that this was an economically advantageous chitin resource compared with crustaceans such as shrimp, crayfish and crab, because it is possible to isolate chitin in a significantly shorter time.
