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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 Antioxidative and antimicrobial edible chitosan films blended with stem, leaf and seed extracts of Pistacia terebinthus for active food packaging(Royal Soc Chemistry, 2018) Kaya, Murat; Khadem, Sanaz; Cakmak, Yavuz Selim; Mujtaba, Muhammad; Ilk, Sedef; Akyuz, Lalehan; Salaberria, Asier M.Methanol extracts of stem, leaf, and seed obtained from Pistacia terebinthus which are rich in phenolic compounds were used for the first time to produce chitosan-based antioxidative and antimicrobial films. All the produced films were characterized by FT-IR, TGA, DSC, SEM, contact angle measurements, and UV-Vis spectroscopy and mechanically. As was expected, incorporation of the plant extracts into chitosan films enhanced the antioxidant and antimicrobial activities effectively. Also, the elasticity of chitosan-seed and chitosan-stem films was improved. The eco-friendly nature of the produced blend films was determined through soil and water degradation analyses. All these findings lead to the conclusion that the produced blend films with Pistacia terebinthus extracts can be applied as alternative food packaging material.Öğe Bat guano as new and attractive chitin and chitosan source(BIOMED CENTRAL LTD, 2014) Kaya, Murat; Seyyar, Osman; Baran, Talat; Turkes, TuncayIntroduction: Chitin is a biopolymer that forms the exoskeleton of arthropods, and is found in the cell walls of fungi. It has a wide range of uses in fields such as cosmetics, pharmacy, medicine, bioengineering, agriculture, textiles and environmental engineering based upon its nontoxic, ecofriendly, biocompability and biodegradability characteristics. Commercially, chitin is obtained from processing the outer skeleton of Crustacea such as shrimp, crab, prawn and crayfish after they have been consumed as food. The study aims to examine the nature of bat guano and to determine if it is a practical source of chitin, which has not been done previously. Results: In this study, the chitin content of dry bat guano samples was found to be 28%. The bat guano, which was collected from Karacamal Cave, came from the bat species Rhinolophus hipposideros. The chitosan yield of this chitin was 79%. The chitin produced from the bat guano was determined to be in the alpha form according to Fourier transform infrared spectroscopy (FTIR) results. The crystallinity of the chitin and chitosan samples was calculated as 85.49 and 58.51% respectively by X-ray crystallography (XRD) experiments. According to scanning electron microscope (SEM) micrographs, the chitin and chitosan structures were shaped like nanofibers. The thermogravimetric analysis (TGA) results showed that both chitin and chitosan had two step weight losses, which are characteristic of these materials. The nitrogen content of the chitin and chitosan was 6.47 and 7.3% respectively according to the elemental analysis results. Conclusions: In this research, it has been observed that bat guano can be considered to be an alternative source of chitin and chitosan to crab, shrimp, crayfish and krill.Öğe COMPARISON OF CHITIN STRUCTURES DERIVED FROM THREE COMMON WASP SPECIES (Vespa crabro LINNAEUS, 1758, Vespa orientalis LINNAEUS, 1771 and Vespula germanica (FABRICIUS, 1793))(WILEY, 2015) Kaya, Murat; Bagriacik, Nil; Seyyar, Osman; Baran, TalatThere has been no study on the chitin structure of wasp species. Here, we selected the three most common wasp species belonging to the family Vespidae for chitin extraction and characterization. Chitin was isolated from each wasp species and characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffractometry (XRD), elemental analysis (EA), and scanning electron microscopy (SEM). The chitin contents of Vespa crabro, Vespa orientalis, and Vespula germanica were 8.3, 6.4, and 11.9%, respectively. The crystalline index (CrI) values for the chitin extracted from each species were 69.88, 53.92, and 50%, respectively. The most important finding of the study is that although the same method was used to extract chitin from each of the three wasp species, the degree of acetylation was different: for V. crabro and V. orientalis it was 96.85 and 99.82% ( the chitin was extremely pure), respectively, whereas that for V. germanica the chitin was 79.83%. (C) 2015 Wiley Periodicals, Inc.Öğe Diatomite as a novel composite ingredient for chitosan film with enhanced physicochemical properties(Elsevier Science Bv, 2017) Akyuz, Lalehan; Kaya, Murat; Koc, Behlul; Mujtaba, Muhammad; Ilk, Sedef; Labidi, Jalel; Salaberria, Asier M.Practical applications of biopolymers in different industries are gaining considerable increase day by day. But still, these biopolymers lack important properties in order to meet the industrial demands. In the same regard, in the current study, chitosan composite films are produced by incorporating diatomite soil at two different concentrations. In order to obtain a homogeneous film, glutaraldehyde was supplemented to chitosan solution as a cross-linker. Compositing diatomaceous earth to chitosan film resulted in improvement of various important physicochemical properties compared to control such as; enhanced film wettability, increase elongation at break and improved thermal stability (264-277 degrees C). The microstructure of the film was observed to haveconsisted of homogeneously distributed blister-shaped structures arised due to the incorporation of diatomite. The incorporation of diatomite did not influence the overall antioxidant activity of the composite films, which can be ascribe to the difficulty radicals formation. Chitosan film incorporated with increasing fraction of diatomite revealed a notable enhancement in the antimicrobial activity. Additionally with the present study, for the first time possible interactions between chitosan/diatomite were determined via quantum chemical calculations. Current study will be helpful in giving a new biotechnological perspective to diatom in terms of its successful application in hydrophobic composite film production. (C) 2017 Elsevier B.V. All rights reserved.Öğe Effect of different animal fat and plant oil additives on physicochemical, mechanical, antimicrobial and antioxidant properties of chitosan films(Elsevier Science Bv, 2018) Akyuz, Lalehan; Kaya, Murat; Ilk, Sedef; Cakmak, Yavuz Selim; Salaberria, Asier M.; Labidi, Jalel; Yilmaz, Bahar AkyuzPractical application of chitosan-essential oil blend films is limited due to the uneconomical extraction procedure of essential oils from plants. This study aimed to produce chitosan films blended with low cost and commercially available oils and fats consumed in daily human diet (olive, corn and sunflower oils, butter and animal fats). The study also focused on how physicochemical, biological and mechanical properties of chitosan blend films were influenced by the incorporation of oils and fats with varying unsaturation degrees. Possible interactions of chitosan film matrix with incorporated oils or fats were investigated. Chitosan-olive oil film showed better surface morphology and higher thermal stability than the films with other unsaturated oils. Tensile strength, Young's modulus and elongation at break were improved by 57.2%, 25.1% and 31.7% for chitosan-olive oil film, respectively. Chitosan-olive oil blend film had the highest antibacterial activity (almost equal to that of commercial antibiotic gentamicin). Edible films obtained from by incorporation of natural oils and fats into chitosan can help produce an environmentally friendly packaging material that is low cost and easily manufactured. (C) 2018 Elsevier B.V. All rights reserved.Öğe False flax (Camelina sativa) seed oil as suitable ingredient for the enhancement of physicochemical and biological properties of chitosan films(Elsevier, 2018) Gursoy, Mehtap; Sargin, Idris; Mujtaba, Muhammad; Akyuz, Bahar; Ilk, Sedef; Akyuz, Lalehan; Kaya, MuratTo overcome the drawbacks of synthetic films in food packaging industry, researchers are turned to natural bio-based edible films enriched with various plant additives. In current study chitosan blend films were produced by incorporating Camelina sativa seed oil at varying concentrations to chitosan matrix. The chitosan blend films were characterized both physicochemically (structural, morphological, thermal, optical and mechanical) and biologically (antimicrobial and antioxidant activity). The incorporation of C sativa seed oil notably enhanced thermal stability, antioxidative, anti-quorum sensing and antimicrobial activity. Except elongation at break, other mechanical properties of the blend films were not affected by incorporation of C sativa seed oil. The surface morphology of blend films was recorded as slightly rough, non-porous and fibre-free surface. As it was expected the optical transmittance in visible region was gradually decreased with increasing fraction of seed oil. Interestingly the hydrophilicity of the blend films revealed a swift increase which can be explained by the formation of micelle between glycerol and Tween 40 in blend films. This study provides valuable information for C sativa seed oil to be used as a blending ingredient in chitosan film technology. (C) 2018 Elsevier B.V. All rights reserved.Öğe How Taxonomic Relations Affect the Physicochemical Properties of Chitin(SPRINGER, 2016) Kaya, Murat; Baublys, Vykintas; Sargin, Idris; Satkauskiene, Ingrida; Paulauskas, Algimantas; Akyuz, Bahar; Yurtmen, HuseyinChitin specimens from 16 arthropod species (13 of Insecta and 3 of Arachnida) were isolated for the first time using the same method. Fourier Transform Infrared Spectrometry (FTIR), Thermogravimetric Analysis (TGA), X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and elemental analysis have been applied to determine how physicochemical properties of chitin specimens are affected by taxonomic relationship. The characterisation studies revealed that physicochemical nature of the chitin specimens differed greatly and were found partially specific to taxa. Significant differences in the surface morphologies of chitin specimens were observed even in the same order. However, the chitin contents were recorded to be specific to the order in the class Insecta. The highest chitin content was observed in Coleoptera (18.2-25.2 %) followed by Hemiptera (10.6-14.5 %), Odonata (9.5-10.1 %), Hymenoptera (7.8-9.3 %), Diptera (8.1 %), Blattodea (4.7 %). In addition, the crystalline index (CrI) values of chitin specimens from Coleoptera were found to be higher than the other orders in Insecta. This study revealed that the chitin contents and CrI values can be related to taxonomical relationships.Öğe Novel, multifunctional mucilage composite films incorporated with cellulose nanofibers(Elsevier Sci Ltd, 2019) Mujtaba, Muhammad; Akyuz, Lalehan; Koc, Behlul; Kaya, Murat; Ilk, Sedef; Cansaran-Duman, Demet; Salaberria Martinez, AsierIn the current study, mucilage composite films were produced by incorporating the cellulose nanofibrils (CNF) at different concentrations i.e., 3 and 6% to chia mucilage matrix by solution casting method. To evaluate the effect of CNF incorporation into mucilage matrix, the obtained composite films were characterized extensively using both physicochemical and biological tools. FT-IR spectra confirmed the composite formation by broader -OH bond peaks than in the spectrum of mucilage control film and shift of C=O stretching vibration peak lower wave number and widen in the mucilage films including cellulose nanofibers. Cellulose nanofibers did not reveal a significant effect on the thermal properties of the all three composite films and dynamic thermogravimetric values were recorded as similar or equal to 287 degrees C. Atomic force microscopy revealed a homogenous distribution of cellulose nanofibers across the mucilage matrix. Dynamic mechanical analysis revealed that the inclusion of cellulose nanofibers in mucilage film led to an enhancement of the tensile modulus as well as the tensile strength, but without reducing the strain at break of the film. Cellulose nanofibers incorporation significantly enhanced the hydrophobic properties of the composite films. The cytotoxicity assay results demonstrated mucilage composite films were nontoxic and have anticancer properties; reducing the viability of cancer cell line by similar or equal to 20% and retaining the cell viability of epithelial cell line by similar or equal to 90%. Cellulose nanofibers incorporation also significantly enhanced the antioxidant and antimicrobial attributes of the mucilage composite films. Overall, the current study provided an idea regarding the biocompatible, non-toxic, highly antioxidative and antimicrobial biodegradable nature of mucilage-CNF composite films, making it a suitable candidate for food and pharmaceutical industry.Öğe Numerical Investigation of Amounts of Heat, Power and Temperature Distribution in IT-SOFC(ELECTROCHEMICAL SOC INC, 2013) Bakal, Ahmet; Kaya, Murat; Mat, Mahmut D.; Jackson, G; Opila, E; Manivanan, A; Markus, T; Walker, RIn this study, thermodynamic and heat transfer concepts were combined to understanding correlation of heat, power and temperature gradient on the cell. All of heat sources and amounts has been determined for electrolyte supported SOFC having 81 cm(2) active area and thus temperature gradient due to each heat source can computed and total temperature distribution clearly has been shown. For this, electrochemical, ohmic, activation and concentration polarization heat sources have been computed by using the boundary conditions taken from the experimental data such as current-voltage-power and mol fraction. Then 80% of the heat generated at 0.7 V and 700 degrees C was removed by the heat transfer and then the maximum temperature difference is found less than 6 degrees C. Also, it was found that the electrical and the heat generations are 25.41 and 23.03 W, respectively.Öğe Potential use of kraft and organosolv lignins as a natural additive for healthcare products(Royal Soc Chemistry, 2018) Gordobil, Oihana; Herrera, Rene; Yahyaoui, Marwa; Ilk, Sedef; Kaya, Murat; Labidi, JalelThe growing interest in substituting synthetic products coming from non-renewable sources with products from biomass has focused attention on the lignin biopolymer. Its high availability, low price and properties make the development of new and valuable uses for lignin interesting, thus improving the economic and environmental aspects of the biomass conversion. To achieve this objective, the potential use of industrial kraft and organosolv lignins as antioxidants, antimicrobials and sunscreen products has been evaluated. The results of a detailed antibacterial and antifungal study demonstrated the high potential of kraft lignins against a variety of foodborne and human pathogenic microorganisms. Moreover, both organosolv and kraft lignins presented an effective protection factor (SPF values from 10-20), demonstrating their effectiveness as natural additives for the sun lotion market. In addition, lignin samples presented high antioxidant capacity compared to butylated hydroxytoluene (BHT), one common commercial antioxidant industrially used. Therefore, the development of innovative applications of lignins as a commodity for the chemical, pharmaceutical or cosmetic industries could expand their possible uses in the market giving new added values to lignin.Öğe Pressurised hot water extraction of phenolic compounds with a focus on eriocitrin and hesperidin from lemon peel(Wiley, 2023) Alasalvar, Hamza; Kaya, Murat; Berktas, Serap; Basyigit, Bulent; Cam, MustafaIn this study, the extraction of bioactive compounds from lemon peel, a by-product of the food industry, was investigated using pressurised hot water extraction (PHWE) at different extraction temperatures (40-200 degrees C) and times (5-30 min) under 10.34 MPa pressure. The selectivity of the PHWE process on eriocitrin and hesperidin extraction was also tested. The highest total phenolic content (TPC) (59.57 mg gallic acid equivalents g(-1)), total flavonoid content (TFC) (8.22 mg catechin equivalents g(-1)) and antioxidant capacity by DPPH (42.59 mg Trolox equivalents (TE) g(-1)) were obtained at 160 degrees C for 30 min. The maximum eriocitrin (30.41 mg g(-1)) and hesperidin (25.90 mg g(-1)) contents were achieved at 160 degrees C for 5 min with a 5-hydroxymethyl furfural content of 0.07 mg g(-1). PHWE provided better results for individual compounds and antioxidant capacities than conventional extraction. The results indicated the potentiality of PHWE in the selective extraction of eriocitrin and hesperidin from lemon peel by controlling the extraction temperature and time.Öğe Production and characterization of chitosan based edible films from Berberis crataegina's fruit extract and seed oil(Elsevier Sci Ltd, 2018) Kaya, Murat; Ravikumar, Preethi; Ilk, Sedef; Mujtaba, Muhammad; Akyuz, Lalehan; Labidi, Jalel; Salaberria, Asier M.Chitosan-based edible films were prepared by supplementing Berberis crataegina DC.'s seed oil and fruit extract into chitosan matrix. The produced films have characterized both physiochemically (SEM, DSC, FT-IR, UV-vis, contact angle and mechanical analysis) and biologically (anti-quorum sensing, antimicrobial and antioxidant). Chitosan-fruit extract film revealed higher thermal stability, antioxidant, antimicrobial and anti-quorum sensing activity compared to other films. Addition of B. crataegina's seed oil and fruit extract into the chitosan film notably decreased the UV-vis transmittance but ameliorate the tensile strength values. Hydrophobicity of the chitosan-seed oil film was observed to be higher (92.64 +/- 4.17) than chitosan-control film (84.67 +/- 1.50) while chitosan-fruit extract film exhibited slightly lower hydrophobicity (73.82 +/- 7.42) than chitosan film. The overall high thermal stability, antioxidant and antimicrobial activity of chitosan-fruit extract film revealed that B. crataegina's fruit extract can be used as an effective ingredient for the production of the edible film with enhanced physicochemical and biological properties.Öğe Supplementing capsaicin with chitosan-based films enhanced the anti-quorum sensing, antimicrobial, antioxidant, transparency, elasticity and hydrophobicity(Elsevier Science Bv, 2018) Akyuz, Lalehan; Kaya, Murat; Mujtaba, Muhammad; Ilk, Sedef; Sargin, Idris; Salaberria, Asier M.; Labidi, JalelIn the current study, capsaicin, a plant alkaloid with high antioxidative, anti-inflammatory, antiobesity, anticancer and analgesic properties, was used in the film technology for the first time. In the same regard, chitosan (as a versatile animal-based polymer) was blended with capsaicin at three different concentrations to obtain edible films. The produced films were characterized by FT-IR, SEM, and DSC. Mechanical, transmittance, hydrophobicity, anti-quorum sensing, antimicrobial and antioxidant properties were also examined. Incorporation of 0.6 mg of capsaicin into the chitosan matrix (200 mg dissolved in 1% acetic acid solution) was observed as an optimal concentration for boosting up three film properties including mechanical, optical and surface morphology. A continuous improvement was recorded in anti-quorum sensing and antimicrobial activities, antioxidative and hydrophobicity with increasing concentration of capsaicin in the film. In further studies, chitosan-capsaicin blend films can be used as a food packaging material as well dermal and wound healing patches. (C) 2018 Elsevier B.V. All rights reserved.
