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Öğe Controlled release and anti-proliferative effect of imatinib mesylate loaded sporopollenin microcapsules extracted from pollens of Betula pendula(Elsevier Science, 2017) Sargın, İdris; Akyüz, Lalehan; Kaya, Murat; Tan, Gamze; Çeter, Talip; Yıldırım, Keyser; Ertosun, Şeymanur; Aydın, Gözde Hatun; Topal, MügeSporopollenin is a promising material for drug encapsulation due to its excellent properties; uniformity in size, non-toxicity, chemically and thermally resilient nature. Herein, morphologically intact sporopollenin microcapsules were extracted from Betula pendula pollens. Cancer therapeutic agent (imatinib mesylate) was loaded into the microcapsules. The encapsulation efficiency by passive loading technique was found to be 21.46%. Release behaviour of the drug from microcapsules was found to be biphasic, with an initial fast release followed by a slower rate of release. Imatinib mesylate release from the drug itself (control) was faster than from imatinib mesylate-loaded sporopollenin microcapsules. The release profiles for both free and entrapped drug samples were significantly slower and more controlled in PBS buffer (pH 7.4) than in HCl (pH 1.2) buffer. Cumulative drug release from IM-MES-loaded sporopollenin microcapsules was found to be 65% within 24 h for PBS, whereas release from the control was completed within 1 h. Also, a complete dissolution of control in HCl buffer was observed within first 30 min. MTT assay revealed that drug-loaded microcapsules were effective on WiDr human colon carcinoma cell line. B. pendula sporopollenin can be suggested as an effective carrier for oral delivery of imatinib mesylate.Öğe Design and application of sporopollenin microcapsule supported palladium catalyst: Remarkably high turnover frequency and reusability in catalysis of biaryls(Academic Press, 2017) Baran, Talat; Sargın, İdris; Kaya, Murat; Menteş, Ayfer; Çeter, TalipBio-based catalyst support materials with high thermal and structural stability are desired for catalysts systems requiring harsh conditions. In this study, a thermally stable palladium catalyst (up to 440 C) was designed from sporopollenin, which occurs naturally in the outer exine layer of pollens and is widely acknowledged as chemically very stable and inert biological material. Catalyst design procedure included (1) extraction of sporopollenin microcapsules from Betula pendula pollens (.25 i.tm), (2) aminofunctionalisation of the microcapsules, (3) Schiff base modification and (4) preparation of Pd(II) catalyst. The catalytic activity of the sporopollenin microcapsule supported palladium catalyst was tested in catalysis of biaryls by following a fast, simple and green microwave -assisted method. We recorded outstanding turnover number (TON: 40,000) and frequency (TOF: 400,000) for the catalyst in Suzuki coupling reactions. The catalyst proved to be reusable at least in eight cycles. The catalyst can be suggested for different catalyst systems due to its thermal and structural durability, reusability, inertness to air and its eco-friendly nature. (C) 2016 Elsevier Inc. All rights reserved.Öğe Incorporation of sporopollenin enhances acid-base durability, hydrophobicity, and mechanical, antifungal and antioxidant properties of chitosan films(Elsevier, 2017) Kaya, Murat; Akyüz, Lalehan; Sargın, İdris; Mujtaba, Muhammad; Salaberria, Asier M.; Labidi, Jalel; Çakmak, Yavuz S.; Koç, Behlül; Baran, Talat; Çeter, TalipSporopollenin-chitosan blend films were produced for the first time. Sporopollenin is a robust structural component of plant pollens exhibiting excellent features such as nontoxicity, biodegradability, biocompatibility, high thermal stability, durability to strong acid and base solutions and homogeneity in size. To benefit from these advantages, sporopollenin samples obtained from Betula pendula (silver birch) were incorporated into chitosan film at different concentration; 10, 20 and 40 mg in 100 mL chitosan gel (1%). Stereo microscopy, FT-IR and TG/DTG analyses showed that sporopollenin was successfully incorporated into the chitosan matrix. Incorporation of sporopollenin in gradually increasing amount into chitosan films was found advantageous in (1) enhancement in chemical durability of the films, (2) increment of hydrophobicity, (3) boosting the mechanical properties, (4) improvement of antifungal and (5) antioxidant activities. This study revealed that sporopollenin can be suggested as an effective blend material for biodegradable edible chitosan film production. (C) 2016 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.Öğe Kastamonu ili (Merkez) atmosferi polen ve spor takvimi (2005-2007)(TÜBİTAK, 2008) Pınar, Münevver; Güney, Kerim; Yıldız, Atila; Çeter, TalipBu projede, kastamonu atmosferi polen ve sporları Aralık 2015-Aralık-2007 tarihine kadar Burkard tuzağı ile toplanmıştır. İki yıllık periyod içende atmosferde bulunan polenlerin ve sporların ait oldukları bitki taksonları saptanmıştır. Polenlerin ve sporların, Kastamonu atmosferindeki miktarları ve polinizasyon dönemleri tespit edilmiştir.Öğe Newly isolated sporopollenin microcages from Cedrus libani and Pinus nigra as carrier for Oxaliplatin; xCELLigence RTCA-based release assay(Springer, 2022) Mujtaba, Muhammad; Akyüz Yılmaz, Bahar; Cansaran Duman, Demet; Akyüz, Lalehan; Yangın, Sevcan; Kaya, Murat; Çeter, Talip; Khawar, Khalid MahmoodSporopollenin-mediated control drug delivery has been studied extensively owing to its desirable physicochemical and biological properties. Herein, sporopollenin was successfully extracted from C. libani and P. nigra pollens followed by loading of a commonly known anticancer drug Oxaliplatin. Drug loading and physicochemical features were confirmed by using light microscopy, FT-IR, SEM and TGA. For the first-time, real-time cell analyzer system xCELLigence was employed to record the Oxaliplatin loaded sporopollenin-mediated cell death (CaCo-2 and Vero cells) in real time. Both the release assays confirmed the slow release of oxaliplatin from sporopollenin for around 40-45 h. The expression of MYC and FOXO-3 genes has been significantly increased in CaCo2 cell and decreased non-cancerous Vero cell confirming the fact that sporopollenin-mediated control release of oxaliplatin is promoting apoptosis cell death preventing the spread of negative effects on nearby healthy cells. All the results suggested that C. libani and P. nigra can be suitable candidates for the slow delivery of drugs.Öğe Pollen morphology of the genus oxytropis DC. in Turkey(Bangladesh Botanical Society, 2013) Çeter, Talip; Karaman Erkul, Seher; Aytaç, Zeki; Başer, BirolPollen morphology of 11 species of the genus Oxytropis DC. (Fabaceae) distributed in Turkey were examined with light (LM) and scanning electron microscope (SEM). Morphology of pollen grains shows isopolar, radially symmetric, tricolporate, prolate or subprolate, porus shape oblate or operculate and exine subtectate. The size varies with the polar axis from 19.52 - 33.31 µm and the equatorial axis from 13.50 - 25.82 µm. There are five ornamentation types: perforate at equatorial section and psilate at polar sections, microreticulate at equatorial sections and psilate at polar sections, microreticulate at equatorial sections and perforate at polar sections, microreticulate at both equatorial and polar sections and perforate at both equatorial and polar sections. Pollen aperture, shape and especially different ornamentation patterns at polar and equatorial section of pollen, as found in this study, appear to be important character. The findings of this study indicate the taxonomic implications of pollen morphology in understanding the similarity and relationships in the genus Oxytropis.Öğe Preparation and characterisation of biodegradable pollen-chitosan microcapsules and its application in heavy metal removal(Elsevier, 2015) Sargın, İdris; Kaya, Murat; Arslan, Gülşin; Baran, Talat; Çeter, TalipBiosorbents have been widely used in heavy metal removal. New resources should be exploited to develop more efficient biosorbents. This study reports the preparation of three novel chitosan microcapsules from pollens of three common, wind-pollinated plants (Acer negundo, Cupressus sempervirens and Populus nigra). The microcapsules were characterized (Fourier transform infrared spectroscopy, thermo-gravimetric analysis, scanning electron microscopy and elemental analysis) and used in removal of heavy metal ions: Cd(II), Cr(III), Cu(II), Ni(II) and Zn(II). Their sorption capacities were compared to those of cross-linked chitosan beads without pollen grains. C. sempervirens-chitosan microcapsules exhibited better performance (Cd(II): 65.98; Cu(II): 67.10 and Zn(II): 49.55 mg g (1)) than the other microcapsules and the cross-linked beads. A. negundo-chitosan microcapsules were more efficient in Cr(III) (70.40 mg g (1)) removal. P. nigra-chitosan microcapsules were found to be less efficient. Chitosan-pollen microcapsules (except P. nigra-chitosan microcapsules) can be used in heavy metal removal. (C) 2014 Elsevier Ltd. All rights reserved.Öğe Türkiye'nin Astragalus L. (Leguminosa) cinsine ait macrophllium bunge, hymenostegis bunge, poterium bunge, megalocystis bunge, halicacabus bunge ve hymenocoleus bunge seksiyonlarının revizyonu(TÜBİTAK, 2014) Karaman Erkul, Seher; Aytaç, Zeki; Ekici, Murat; Önde, Sertaç; Çeter, TalipBu çalışmada Türkiye'de yayılış gösteren Astragalus (Leguminosae) Cinsine Ait Macrophyllium, Hymenostegis, Poterion, Hymenocoleus ve Anthylloidei seksiyonlarının revizyonu yapılmıştır. Çalışmamız sonucunda Macrophyllium seksiyonundaki tür sayısı 6, Hymenostegis seksiyonundaki tür sayısı 12, Hymenocoleus seksiyonundaki tür sayısı 1, Poterion seksiyonundaki tür sayısı 2, Anthylloidei seksiyonundaki tür sayısı 9 olarak belirlenmi?tir. Hymenocoleus seksiyonunun ve A. trifoliastrum türünün adı korunmuştur. A. expetitus, A. chrysostachys, A. persicus, A. pereshkhoranicus ve A. marivanensis türlerinin Türkiye?de bulunmadığı, A. rubrostriatus ve A. qoturensis türlerinin Türkiye Florası için yeni kayıt olduğu tespit edilmiştir. A. yukselii yeni tür olarak yayınlanmıştır.
