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Öğe Antimicrobial and Antioxidant Properties of Ceriodaphnia quadrangula Ephippia Chitosan(Ars Docendi, 2016) Asan-Ozusaglam, Meltem; Cakmak, Yavuz Selim; Kaya, Murat; Erdogan, Sevil; Baran, Talat; Mentes, Ayfer; Saman, IhsanThe chitosan from ephippia of Ceriodaphnia quadrangula (Crustaceae) has been fully characterized in our previous study, and in this work it was tested for antibacterial and antifungal activities against human and fish pathogens, while also determining its antioxidant activities. Using the disc diffusion method showed that the antimicrobial activity was observed against all tested microorganisms in the range of 12.84 -16.28 mm. The minimal bactericidal concentration (MBC) value was found to be 0.63 - 2.50 mg/ml. Chitosan obtained from C. quadrangula ephippia showed higher antimicrobial activity against some pathogenic bacteria than commercial antibiotics. While chitosan inhibited 35.83% of the 1,1-diphenyl-2-picrylhydrazyl radicals (at 5 mg/ml), it showed an activity of 14.48 mu g/ml for ferrous ion reducing. Consequently, it is suggested that chitosan obtained from the ephippia of C. quadrangula (Crustacea) can be used as food/feed additives, preservatives or in the pharmaceutical industry instead of using synthetic antimicrobials and antioxidants.Öğe Characterisation of ?-chitin extracted from a lichenised fungus species Xanthoria parietina(Taylor & Francis Ltd, 2015) Kaya, Murat; Halici, Mehmet Gokhan; Duman, Fatih; Erdogan, 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 Characteristics of corneal lens chitin in dragonfly compound eyes(Elsevier Science Bv, 2016) Kaya, Murat; Sargin, Idris; Al-jaf, Ivan; Erdogan, Sevil; Arslan, GulsinChitin in the compound eyes of arthropods serves as a part of the visual system. The quality of chitin in such highly specialised body parts deserves more detailed examination. Chitin in the corneal (ommatidial) lenses of dragonfly (Sympetrum fonscolombii) compound eyes was isolated by using the classical chemical method. The chitin content of the corneal lenses was determined to be quite high (20.3 +/- 0.85%). The FT-IR analysis showed that corneal lens chitin was in the alpha-form as found in all arthropod species where mechanical strength is required. The surface morphology analysis by scanning electron microscopy revealed that the outer part of corneal lenses consisted of long chitin fibrils with regular arrays of papillary structures while the smoother inner part had concentric lamellated chitin formation with shorter chitin nanofibrils. Chitinase enzymatic digestion studies, elemental analysis results and the degree of acetylation value showed the purity of chitin samples from corneal lens. The maximum degradation temperature value of the corneal lens chitin was observed at 369.2 degrees C. X-ray analysis revealed that corneal lens chitin has high crystallinity index; 96.4%. Identification of chitin found in ommaditia of insect compound eyes can provide insights into insect vision and chitin-based optical material design studies. (C) 2016 Elsevier B.V. All rights reserved.Öğe Chitin extraction and characterization from Daphnia magna resting eggs(Elsevier Science Bv, 2013) Kaya, Murat; Sargin, Idris; Tozak, Kabil Ozcan; Baran, Talat; Erdogan, Sevil; Sezen, GoksalNew application areas for chitin and its derivatives have been extensively investigated and there is a solid, growing demand for new chitin sources. In this present study, chitin content of Daphnia magna resting egg (18-21%) was determined for the first time. FTIR, elemental analysis, TGA, XRD and SEM studies revealed the structural and thermal properties of extracted alpha-chitin. This study suggests that D. magna resting eggs can be exploited as an attractive alternative chitin source. (C) 2013 Elsevier B.V. All rights reserved.Öğe Chitosan and nano-TiO2 coating improves the flame retardancy of dyed and undyed denim fabrics by increasing the charring(Sage Publications Inc, 2022) Becenen, Nilgun; Erdogan, SevilIn this study, chitosan is obtained from the waste shells of crayfish (Astacus leptodactylus) and characterized. The crayfish chitosan was coated on cotton fabrics using the padding-drying method. The surface properties, flammability and water and air permeability properties of these coatings based on chitosan and a combination of chitosan and nano-TiO2 were determined. The weight of green calico fabric increased to 24.76% after coating with chitosan, while the weight of the blue dyed denim fabric increased to 5.19%. The chitosan coating increased the tear strength of the calico fabric by 20% in the weft direction. Thermogravimetric analysis and vertical burning tests show that chitosan improves the thermal resistance and flame retardancy performance of denim fabrics. While the amount of residue due to thermal degradation of the blue dyed denim fabric was 16.78%, it increased to 34% after coating with chitosan+nano-TiO2. The chitosan coating reduced the mass loss caused by thermal degradation in green calico fabric from 86.3% to 66.0%. Chitosan also improved the post-flame combustion performance of fabrics. While the ember burning time is decreased to 6s in the chitosan-coated dyed calico fabric, this did not occur in the chitosan+nano-TiO2-coated dyed denim fabric.Öğe Comparison of antimicrobial activities of newly obtained low molecular weight scorpion chitosan and medium molecular weight commercial chitosan(Soc Bioscience Bioengineering Japan, 2016) Kaya, Murat; Asan-Ozusaglam, Meltem; Erdogan, SevilIn this study the antimicrobial activity of low molecular weight (3.22 IrDa) chitosan, obtained for the first time from a species belonging to the Scorpiones, was screened against nine pathogenic microorganisms (seven bacteria and two yeasts) and compared with that of medium molecular weight commercial chitosan (MMWCC). It was observed that the antimicrobial activity of the low molecular weight scorpion chitosan (LMWSC) was specific to bacterial species in general rather than gram-negative or gram-positive bacterial groups. It was also determined that LMWSC had a stronger inhibitory effect than the MMWCC, particularly on the bacterium Listeria monocytogenes and the yeast Candida albicans, which are important pathogens for public health. In addition, it was recorded that the MMWCC had a greater inhibitory effect on Bacillus subtilis than LMWSC. According to the results obtained by the disc diffusion method, the antibacterial activity of both LMWSC and MMWCC against B. subtilis and Salmonella enteritidis was higher than the widely used antibiotic Gentamicin (CN, 10 mu g/disc). (C) 2015 The Society for Biotechnology, Japan. All rights reserved.Öğe Comparison of chitin structures isolated from seven Orthoptera species(Elsevier, 2015) Kaya, Murat; Erdogan, Sevil; Mol, Abbas; Baran, TalatDifferences in the physichochemical properties of the chitin structure of the exoskeleton of seven species from four genera were investigated in this study. The same method was used to isolate the chitin structure of the seven species. The physicochemical properties of the isolated chitins were revealed by ESEM, FTIR, TGA and XRD analyses. The FTIR, TGA and XRD results from the chitin samples were similar. The surface morphologies of the chitins were investigated by ESEM and interesting results were noted. While the surface morphologies of the chitins isolated from two species within the same genus were quite different, the surface morphologies of chitins isolated from species belonging to different genera showed similarity. It was determined that the dry weight chitin contents of the grasshopper species varied between 5.3% and 8.9%. The results of molecular analysis showed that the chitins from seven Orthoptera species (between 5.2 and 6.8 kDa) have low molecular weights. Considering that these invasive and harmful species are killed with insecticides and go to waste in large amounts, this study suggests that they should be collected and evaluated as an alternative chitin source. (C) 2014 Elsevier B.V. All rights reserved.Öğe The Dynamics of Zooplankton in National Park of Lake Gala (Edirne-Turkey)(Inst Zoology, Bas, 2011) Guher, Huseyin; Erdogan, Sevil; Kirgiz, Timur; Camur-Elipek, BelginIn this study, carried out at monthly intervals in four different stations between March 2004 and January 2005, it is aimed to have new knowledge on the dynamics of zooplankton communities and the effects of physical-chemical values of the Lake Gala. As a result of the study, a total of 76 species have been identified as 50 species belong to Rotifera, 15 species - to Cladocera, and 11 species - to Copepoda. Of these species Proalides tentaculatus de Beuchamp, 1907, Itura myersi WULFERT, 1935, Asplanchnopus hyalinus (HARRING, 1913) are found only in Turkish Thrace. As a result of quantitative evaluation of zooplankton samples, while an average of 35 334 ind./m(3) Rotifera, 19 305 ind./m(3) Cladocera, 72 369 ind./m(3) Copepoda was found an average of 127 008 ind./m(3) zooplankton organisms have been determined in the lake. According to the results of PCA analysis, when looking at the seasonal distribution of zooplankton species, it is seen that species assembled to form three groups as species which appear in spring, summer and winter. According to the results of RDA analysis, correlation (for RDA axis 1 0.956, for RDA axis 2 0.925) between zooplankton organisms and environmental variables being so high shows that Water tem, EC, SO4, Ca, pH, Chl-a, Secchi and PO4, are significant (p = 0.0020) factors determining the distribution of zooplankton organisms in the Lake Gala.Öğe Four New Rotifera Species of Turkish Fauna(Central Fisheries Research Inst, 2012) Erdogan, Sevil; Guher, HuseyinFour rotifer species were recorded from 3 freshwater bodies (Pedina and Hamam Lakes, Igneada-Kirklareli and Omerbey Stream, Uzunkopru- Edirne) in Turkish Thrace. These species, Trichocerca bicristata (Gosse, 1887), Gastropus minor (Rousselet, 1892), Erignatha clastopis (Gosse, 1886) and Encentrum kulmatyckii Wiszniewski, 1953, are new records for the Turkish fauna. Besides, the recorded species are illustrated and aspects of their distribution are represented.Öğe GENDER INFLUENCES DIFFERENTIATION OF CHITIN AMONG BODY PARTS(Wiley-Blackwell, 2016) Kaya, Murat; Bulut, Esra; Mujtaba, Muhammad; Sivickis, Karolis; Sargin, Idris; Akyuz, Bahar; Erdogan, SevilEarlier reports have established that chitin isolates from each body part of an insect cuticle can exhibit diverse physicochemical properties. But it is still unknown if the gender of the insect can influence characteristics of chitin isolates from different body parts. The present study addresses this question. As a result, important physicochemical differences in the chitin samples from different body parts of Melolontha sp. were recorded on the basis of sex. The chitin samples were extracted from eight different body parts (antennae, head, eyes, thorax, abdomen, elytra, hindwings, and legs) of female and male. The most remarkable variations in the chitin isolates from female and male body parts were recorded in chitin content, crystallinity, thermal stability, and surface morphology. And also it was wondered these chitin isolates from different body parts of female and male could find different applications. To check this hypothesis, the chitin samples from female and male were interacted with bovine serum albumin (BSA) protein and important variations were observed. (C) 2016 Wiley Periodicals, Inc.Öğe High similarity in physicochemical properties of chitin and chitosan from nymphs and adults of a grasshopper(Elsevier Science Bv, 2016) Erdogan, Sevil; Kaya, MuratThis is the first study to explain the differences in the physicochemical properties of chitin and chitosan obtained from the nymphs and adults of Dociostaurus maroccanus using the same method. Fourier transform infrared spectroscopy, thermogravimetric analysis and x-ray diffraction analysis results demonstrated that the chitins from both the adults and nymphs were in the alpha-form. The chitin contents of the adults (14%) and nymphs (12%) were of the same order of magnitude. The crystalline index values of chitins from the adult and nymph grasshoppers were 71% and 74%, respectively. Thermal stabilities of the chitins and chitosans from adult and nymph grasshoppers were close to each other. Both the adult (7.2 kDa) and nymph (5.6 kDa) chitosans had low molar masses. Environmental scanning electron microscopy revealed that the surface morphologies of both chitins consisted of nanofibers and nanopores together, and they were very similar to each other. Consequently, it was determined that the physicochemical properties of the chitins and chitosans from adults and nymphs of D. maroccanus were not very different, so it can be hypothesized that the development of the chitin structure in the nymph has almost been completed and the nymph chitin has the same characteristics as the adult. (C) 2016 Elsevier B.V. All rights reserved.Öğe An investigation on the periphytic species of Rotifera in the Lake Gala (Turkey)(Inst Zoology, Bas, 2008) Erdogan, Sevil; Guher, HuseyinThis study was performed to determine the Rotifera species living on the Thypha sp., Nymphaea sp. and Ceratophyllum sp., and to put forward their macrophyte preferences, if they have been present in the Lake Gala National Park between June and December 2004. The effects of the physico-chemical parameters, which were measured in the lake, and the chlorophyl-a values of the macrophytes on the distribution of Rotifera species were also examined. As a result of the study totally 39 Rotifera species, belonging to 13 families, were found. Thirtytwo species on Thypha sp., 29 species on Nymphaea sp. and 21 species on Ceratophyllum sp. were determined. It was determined that Keratella tropica and Polyarthra remata prefered the Thypha sp., Trichotria pocillum and Lecane luna preferred the Nymphaea sp., Lecane quadridentata, Habrotrocha sp. and Rotoria rotatoria preferred the Ceratophyllum sp.Öğe Kitosan ile Ön İşlem Görmüş Pamuklu Kumaşın Asit Boyalarla Tek Adımda Renklendirilmesi(Trakya Üniversitesi, 2020) Yüce, İsmail; Erdogan, Sevil; Becenen, Nilgun; Şen, HayriArtan küresel kirlilik tehditleri, doğal üretim kaynaklarının azalma oranı ve yeni yasal çevre düzenlemeleri, tekstil üretimde çevre ile uyumlu yeni malzemelerin kullanımını ve doğal atıkların değerlendirilmesini zorunlu hale getirmektedir. Bu çalışmada pamuklu kumaşların asit boyarmaddeler ile boyanmasında, kabuklu organizmaların atık kabuklarından elde edilen, biyolojik olarak bozunabilir doğal bir biyopolimer olan kitosanın etkisi araştırılmıştır. Ticari kitosan ile işlem görmüş ve görmemiş pamuklu kumaşlar, asit boyarmaddeler ile farklı reçetelerde boyanmış ve bu kumaşların renk verimleri, yıkama haslık özellikleri ve atık flottenin iletkenlik değerleri ölçülerek sonuçlar karşılaştırılmıştır. Çalışma sonucunda, pamuklu kumaşın kitosan ile ön işlem gördükten sonra naylon ve yün elyaf renklendirilmesinde kullanılan asit boyarmaddeler ile tuz ve başka bir kimyasal gerektirmeden, istenilen renk şiddetinde ve yeterli yıkama haslık değerlerinde boyanabileceği tespit edilmiştir. Aynı zamanda boyama atık flottesinin iletkenlik değerlerinin, kitosan kullanılarak azaltılabileceği ortaya konmuştur.Öğe Morphological examination of the resting egg structure of 3 cladoceran species [Ceriodaphnia quadrangula (OF Muller, 1785), Daphnia longispina (OF Muller, 1776), and D. magna Straus, 1820](Tubitak Scientific & Technological Research Council Turkey, 2014) Kaya, Murat; Erdogan, SevilMorphological characteristics of the resting egg, which is important to ensure the continuity of generations, were examined to understand if there were morphologically significant differences among 3 cladoceran species. Resting eggs floating on the water surface were collected by a plankton net with a mesh size of 100 mu m from Mamasin Dam Lake in November 2012 and were left to dry at room temperature in the laboratory. In this study, the size, shape, and color of the ephippium and the size of the egg/eggs enclosed in the ephippium were comparatively analyzed by stereomicroscope and scanning electron microscope. It was observed that each resting egg type had its own characteristic shape and color. Results of the statistical analysis showed that there were statistically significant differences between the sizes of the ephippium and egg/eggs enclosed in the ephippium of the resting egg of each species. We concluded that the morphological features of the resting eggs of 3 species are different from each other and that these characters can be used for species identification. In addition, we described morphological features of the resting eggs of the 3 cladoceran species in detail, gave extra information about color and size differences, and contributed to improving the literature knowledge of these species with this study.Öğe A physicochemical characterization of fully acetylated chitin structure isolated from two spider species: With new surface morphology(Elsevier Science Bv, 2014) Kaya, Murat; Seyyar, Osman; Baran, Talat; Erdogan, Sevil; Kar, MusaSpiders are a huge group which includes more than 44,000 species. But there has been no study of the chitin structure of spiders. In this study we physicochemically characterized chitin structure of two common spider species (Geolycosa vultuosa and Hogna radiata). Chitin content was determined as 8-8.5% for G. vultuosa and 6.5-7% for H. radiata. FTIR, TGA and XRD results showed that the chitin structures are in a-form. Environmental scanning electron microscopy (ESEM) revealed that the surface morphology of each species is different. Chitin yielded from G. vultuosa has two different pore structures. The type one pore is rarely sequenced and its size ranges between 190 and 240 nm, while the type two pore is tightly sequenced and its size ranges between 11 and 32 nm. There is no information in previous studies about the chitin structure with two different pore morphologies. A new chitin surface morphology has been determined in G. vultuosa. The chitin isolated from H. radiata, has classic morphology: nanofibre structures (10-17 nm) and 195-260 nm sized pores. Acetylation degree of the chitin samples was calculated as 97% for G. vultuosa and 99% for H. radiata in accordance with elemental analysis results. (C) 2014 Elsevier B.V. All rights reserved.Öğe Physicochemical comparison of chitin and chitosan obtained from larvae and adult Colorado potato beetle (Leptinotarsa decemlineata)(Elsevier Science Bv, 2014) Kaya, Murat; Baran, Talat; Erdogan, Sevil; Mentes, Ayfer; Ozusaglam, Meltem Asan; Cakmak, Yavuz SelimChitins and chitosans obtained from larva and adult Coloradopotato beetles (Leptinotarsa decemlineata) were physico-chemically characterized and differences between adults and larvae were identified. The dry weight chitin contents of the adult Colorado potato beetles and larvae were determined as 20% and 7%, respectively. The chitin produced chitosan yields of 72% from the adult Colorado potato beetles and 67% from the larvae. FTIR analysis showed that the isolated chitins were in the alpha form. Crystalline index values, determined by XRD, were 72% for larvae and 76% for adults. The degradation temperatures of the isolated chitin structures were measured by TGA, and this showed that the chitin from adult Colorado potato beetles had a more stable structure than that from the larvae. The surface morphologies of the isolated chitin and chitosan structures were analysed with SEM and it was revealed that these structures consisted of nanofibres. According to elemental analysis, the purity of chitin and chitosan from adults was greater than that from the larvae. The results of molecular analysis showed that the chitosans from adults (2.722 kDa) and larvae (2.676 kDa) of the Colorado potato beetle have low molecular weights. Antimicrobial and antioxidant activities of both adult and larval chitosans were determined. The adult potato beetle is more appropriate than the larvae as an alternative chitin source because of the fact that its dry weight chitin content, chitosan yield and purity of chitin are higher than those from the larvae, and its antimicrobial and antioxidant activities are also higher than those from the larvae. (C) 2014 Elsevier B.V. All rights reserved.Öğe Porous and nanofiber ?-chitosan obtained from blue crab (Callinectes sapidus) tested for antimicrobial and antioxidant activities(Elsevier, 2016) Kaya, Murat; Dudakli, Fatma; Asan-Ozusaglam, Meltem; Cakmak, Yavuz Selim; Baran, Talat; Mentes, Ayfer; Erdogan, SevilChitin was isolated using the classical chemical method from the shell of Callinectes sapidus. The chitin content in the dry weight of the crab shells was determined as 12.1%. Total chitosan yield was recorded as 76%. The deacetylation degree of the chitosan was found to be 82.5%. The obtained chitin was in the alpha-form which was confirmed from the results of FTIR, TGA and XRD analyses. Resulting chitin showed DTG max value as 390 degrees C while in same regard chitosan show this value as 306 degrees C. Detailed information about the composition of pores and nanofibers was obtained using SEM. Disc diffusion method used for testing the antimicrobial activity, inhibition zone diameters of the chitosan from C. sapidus varied between 15.28 and 20.21 mm for human bacterial pathogens, between 15.51 and 16.25 mm for fungal pathogens and between 14.22 and 15.75 mm for fish bacterial pathogens, respectively. MBC and MFC values of the chitosan from C sapidus were between 0.16 and 2.50 mg/mL. The results of DPPH and ferric ion reducing power activity used for determining the antioxidant activity of the chitosan, were found as IC50: 5.99 and EC50: 6.16, respectively. (C) 2015 Elsevier Ltd. All rights reserved.Öğe Pre-assessment of zoobenthos diversity from the only hard coral Marine Reserve in the Turkish Seas (Canakkale Strait, Turkey)(Elsevier, 2022) Ozalp, H. Baris; Demir, Volkan; Evcen, Alper; Onen-Tarantini, Senem; Montesanto, Federica; Erdogan, Sevil; Culha, MehmetMarine Protected Areas (MPAs) and their management have become more significant than ever due to the growing impacts of pollution, overfishing and illegal hunting activities in marine environments. Corals, as habitat forming species that create biodiversity hotspots, provide structural support, shelter and a nursery ground for associated biota. The present paper deals with the pre-assessment of invertebrate assemblages living in hard coral (Cladocora caespitosa) reef in the marine protected area (Dardanos Cladocora Reefs) of the Canakkale Strait. In the study (DarINVERTA7) conducted between 2017 and 2021, 62 benthic invertebrate species, belonging to eight taxonomic groups were reported for the first time from the region of which five species (Clathria (Clathria) compressa, Rynchozoon neapolitanum, Hornera frondiculata, Polycitor adriaticus and Aplidium nordmanni) were new for the Turkish coasts.(c) 2022 Elsevier B.V. All rights reserved.Öğe Radiation synthesis and characterization of chitosan/hyraluronic acid/hydroxyapatite hydrogels: drug uptake and drug delivery systems(Elsevier Science Bv, 2018) Tasdelen, Betul; Erdogan, Sevil; Bekar, BahadirIn this work, a new chitosan (CS)/hyaluronic acid (HA)/hydroxyapatite (HAP) hydrogels were synthesized by using gamma rays irradiation technique for oral delivery of drugs. The hydrogelss were characterized using fourier transform infrared spectroscopy (FTIR) and the physicochemical properties of shrimp chitosan was determined with both FTIR and scanning electron microscopy (SEM). The use of the hydrogel samples as a drug delivery system was investigated by an anticancer drug. 5-Fluorouracil (5-FU) was used as a model anticancer drug to investigate the drug uptake and release kinetics of hydrogels. The properties of the hydrogels were evaluated in terms of swelling, drug uptake and release behaviours. The addition of hyaluronic acid and hydroxyapatite in the gel structure improved drug uptake and release capability of the new hydrogels. (c) 2018 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of 14th International Conference on Nanosciences & Nanotechnologies (NN17).Öğe Testing the habitat selectivity of bdelloid rotifers in a restricted area(Tubitak Scientific & Technological Research Council Turkey, 2015) Kaya, Murat; Erdogan, SevilThe biodiversity of microorganisms is still not understood exactly because they are very small and diverse and it requires an intensive effort to examine them. In this study, we tested whether there were differences in species richness and species composition among six sampled habitats to understand the biodiversity pattern of bdelloid rotifers. To test habitat preferences of bdelloid rotifers, 90 samples were collected from six different habitats (soil, tree bark, one species of lichen (Lecanora muralis), and three species of moss (Grimmia pulvinata, Homalothecium lutescens, and Tortula ruralis)) in the village of Tasci in December 2008. We performed an analysis of variance (ANOVA) followed by a Tukey honestly significant difference (HSD) test to understand whether species richness was significantly different among the six habitats. Analysis of similarity (ANOSIM) was used to test whether differences in species composition between habitats were higher than those between samples within each habitat. The results showed that species richness in each sample was significantly different among habitats (ANOVA: F-5,F-84 = 19.3, P < 0.0001) according to the Tukey HSD test. Differences in species composition between samples between habitats were significantly higher than differences in species composition between samples within each habitat (ANOSIM: R = 0.40, P = 0.001).
