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Öğe BAZI AMİNOASİT GÜMÜŞ TUZLARININ SENTEZİ VE KARAKTERİZASYONU(Düzce Üniversitesi, 2018) Aydın, Pinar; Karagül, Bora; Karadeniz, Seref; Uğraş, Halil İbrahimAminoasitler fizyolojik olarakbirçok hayatı fonksiyonun yerine getirilmesinde önemli rol oynayan proteinlerinyapı taşlarını oluşturmaktadırlar. Son yıllarda yapılan bir çok çalışmadaaminoasitlerin bu önemli fizyolojik görevinin yanı sıra bir çok alanda dakullanım sahasının olduğu ortaya çıkarılmıştır. Bu önemli kullanım alanlarından bir tanesi de aminoasitlerin korozyonönleyici etkilerinin belirlenmesine yönelik gerçekleştirilen çalışmalarolmuştur. Gerçekleştirilen çeşitli çalışmalarda doğal aminoasitlerin çeşitlimateryaller üzerindeki korozyon inhibitörü etkileri incelendiği gibi bazıaminoasitlerden elde edilen iyonik sıvıların da korozyon inhibitörü özellikleride yoğun bir şekilde incelenmiştir. Gerçekleştirmiş olduğumuz bu çalışmadaçeşitli katyonik merkezli prokesörler ile anyon değişim reaksiyonu vererekiyonik sıvılar elde etmeye aday bazı aminoasit gümüş tuzlarının sentezigerçekleştirilmiştir. Sentezlenen bileşiklerin yapıları FouirerTransform Infrared Spektrofotometresi (FT-IR) ve ihtiva ettikleri gümüşatomu miktarları ise Inductively Coupled Plasma Mass Spectrometer (ICP-MS)Spektrofotometresi ile tayin edilmiştir.Öğe Determination of taxanes by validated LC-MS/MS method in hazelnut collected from different regions and altitudes in Turkey(Acg Publications, 2018) Oğuzkan, Sibel Bayıl; Karagül, Bora; Aksoy, Elif Sine; Uzun, Ayşe; Can, Merve; Yılmaz, Hasibe; Gören, Ahmet C.In this study, mass fractions of paclitaxel, cephalomannine, 10-DAB III and baccatin III in hazelnut were measured with new and validated LC-MS/MS method. Green outer nut husk and nutshell of Turkish hazelnut (Corylus colurna L.) were collected from Duzce, Trabzon, Adapazari and Samsun at several altitudes during August and September in 2014. The target analytes were prepared using solid-liquid extraction and analysed by LC-MS/MS. High amount of baccatin III, used for synthesizing semi-synthetic paclitaxel, was found in the nutshells collected at 250-500 m altitude in Cumayeri district of Duzce. In the husk samples from Vakfikebir district of Trabzon, the highest amount of baccatin III was obtained. The mass fractions of baccatin III in nutshell and husks were between 164.38-1020.85 mu gkg-1 and 166.12-923.64 mu gkg-1, respectively.Öğe Effects of Some Adsorbents on the Pre-purification of Taxol (Anticancer Drug) from Hazelnut Nutshells(Asian Network Scientific Information-Ansinet, 2018) Oğuzkan, Sibel Bayıl; Karadeniz, Şeref; Karagül, Bora; Uzun, Ayşe; Aksoy, Elif Sine; Güler, Özen Özensoy; Uğraş, Halil İbrahimBackground and Objective: The most important pharmaceutically active substance in plant-derived chemotherapy drugs is paclitaxel. Taxane compounds such as paclitaxel, cephalomannine, baccatin III and 10-Deacetylbaccatin III are found in hazelnut shells of Turkey's Black Sea region. This study aimed to determine the most effective adsorbent on the purity and efficiency of these taxane compounds from nutshells. Materials and Methods: The adsorbent effect on the purification of taxane compounds from hazelnut shells was studied using different adsorbent materials. For this purpose, extracts were obtained from samples of hazelnut shells collected, dried and ground into solvents. The resulting extract was concentrated into a stock solution. Samples taken from the stock solution were separately treated with seven different adsorbent materials and then filtered and analyzed with HPLC (High Performance Liquid Chromatography). Results: The HPLC analysis of taxane compounds determined on taxane, both the purification and whether or not the substance was lost, by measuring the efficiency at the same time. Graphene-oxide was found to be the adsorbent with the highest positive effect on the purification of paclitaxel in hazelnut nutshells in all cases. Graphene-oxide also had the least loss in terms of paclitaxel yield efficiency in hazelnut nutshells. Conclusion: The effects of adsorbent treatment increased both the purity and efficiency of taxane compounds and was, thus, a useful pre-purification method for shells obtained from Turkish hazelnuts. This shell waste material may prove to be a good alternative source of taxol as an anticancer drug.Öğe Effects on Antibacterial and DNA Protection of Organic Dyestuff Extracts Obtained from Hazelnut Nuthusk(2017) Oğuzkan, Sibel Bayıl; Karagül, Bora; Kütük, Esra; Kılıç, İbrahim Halil; Uğraş, Halil İbrahimHazelnut is of great important in agricultural export of our country. It has an annual export of one and a half billion dollars. Every new product that will increase the value of the nut is very important. In recent years, natural dye materials used especially in textile materials are important and those of plant origin are preferred. For this purpose, we have made a natural dye extracts from hazelnut nuthusk after collected, dried and grinded of samples. Some biological activities have been carried out showing the suitability for industrial use of the dye extracts obtained from hazelnut nuthusk. Within the scope of our study, the effect of extracts obtained from the hazelnut nuthusk of the Düzce region was evaluated on anti-bacterial and DNA protection. From the extracts obtained, antibacterial activity tests were analyzed by disk diffusion method using 3 different standard bacterial strains as S. aureus, E. coli and P. aeruginosa. pBR322 plasmid DNA and UV-C method was used for DNA protective activity. Four different extracts of dyestuff has showed antibacterial activities to S. Aureus and two different of them P. aeruginosa but none of the samples antibacterial properties to E. coli bacterial strains. It has been determined that the all of dyestuffs extracts obtained from the hazelnut nuthusk have potential for protection against the effects of UV-C and H2O2 on DNAÖğe In vitro cytotoxic and genotoxic effects of newly synthesised boron ionic liquids(Taylor & Francis Ltd, 2019) Oğuzkan, Sibel Bayıl; Türkez, Hasan; Karagül, Bora; Çakır, Ümit; Uğraş, Halil İbrahimIn this study, new molecules containing boron were added to the family of ionic organic compounds, in particular, ionic liquids with a cationic center. This study aimed to determine the cytotoxic and genetic effects of a total of four newly synthesised borenium and borinium compounds on human peripheral lymphocytes in vitro. Human peripheral lymphocytes were obtained from heparinised blood samples collected from healthy females aged between 29 and 32 years, with no history of exposure to toxic agents. The cytotoxicity was assayed via the MTT (3-(4.5-dimethylthiazole- 2-yl)-2.5-diphenyltetrazolium-bromide) and LDH (lactate dehydrogenase) tests; the genotoxicity and cytotoxicity, via the micronucleus (MN) and sister chromatid exchange (SCE) tests. The results showed that the borenium compounds did not exhibit cytotoxic activity in the MTT and LDH tests even in high concentrations, the borinium compound did not exhibit cytotoxic effects in lower concentrations in vitro. The borenium compounds did not show genotoxic effects in SCE and MN tests. However, at a high concentration, borinium increased the micronucleus rate in comparison to the negative control group. The obtained results suggest that these newly synthesised cationic boron compounds can be used reliably in health, cosmetics or other industries, taking into consideration their types and concentrations.Öğe Investigation of Some Quality Criteria in Chestnut Honey of Düzce Province(Düzce Üniversitesi, 2023) Yoldas, Taner; Karagül, Bora; Düvenci, Elif SineHoney is a natural food source that has been consumed by humans for thousands of years and has an important place in various cultures. Chestnut honey is an important type of honey produced in Düzce province. Determining the quality and purity of honey ensures that consumers have access to safe, high-quality honey. The control criteria for the suitability of honey for human health consumption are defined in the Turkish Food Codex Communiqué on Honey (2020/7). Düzce University Scientific and Technological Research Application and Research Center (DÜBİT) responds to requests for honey analysis for non-commercial, internal quality control purposes. In this study, the results of honey samples produced in the province of Düzce and analyzed in the laboratories of DÜBİT were examined according to the criteria of the Turkish Food Codex Communiqué on Honey and an evaluation of the results was carried out. According to the test results, 38%, 20% and 16% of the samples were found to be unsuitable for the quality criteria, especially for the sugar profile, conductivity and proline parameters, respectively. Additionally, pollen analysis of 13% of the honey samples revealed pollen densities that did not match the declared plant family. From a public health point of view, it is important to consume high-quality, reliable and natural honey products. Therefore, quality control of bee products should be carried out from the producer to the consumer.Öğe Paklitakselin saflaştırılması için yeni adsorban sentezi(Düzce Üniversitesi, 2017) Karagül, Bora; Uğraş, Halil İbrahimPaklitaksel en etkin kemoterapi ilacıdır. Saflaştırılması ve elde edilmesi oldukça zor ve maliyetlidir. Bu yüzden saflaştırılması için tübülin ile olan etkileşimini temel alarak yeni adsorbanlar sentezledik. Tübülin ve paklitaksel spesifik olarak etkileşmektedir. Sentezlediğimiz ürünler sadece paklitaksel için değil aynı zamanda diğer safsızlık giderimlerinde de adsorban olarak kullanılabilir. Amaçlarımızdan biri de bu sentezleri literatüre kazandırmak ve başka alanlarda değerlendirilmesini sağlamaktır. Paklitakselin saflaştırma süreci uzun süredir endüstride ciddi sıkıntılı bir konu olmaktadır. Paklitakselin saflaştırma ve izolasyon işlemleri genel olarak birden fazla basamak içermektedir; biyokütlenin organik solvent ile ekstraksiyonu, safsızlıkların giderilmesi için bir veya daha fazla zenginleştirilmiş basamaklar ve çoklu kromatoğrafik saflaştırma basamaklarıdır. Ayrıca, bitki ekstraktından kaynaklanan yüksek seviyedeki katran, yağımsı, fenolik ve mumsu bileşenler gibi safsızlıklar fazla organik çözücü tüketilmesine ve HPLC kolon ömrünün azalmasına neden olabilmektedir. Bu yüzden, farmasötik derecede paklitakselin endüstride ön saflaştırma işlemleri HPLC çalışmaları öncesinde hayati rol oynamaktadır. Bu çoğunlukla başlangıçtaki ekstraktların istenmeyen bileşenlerinin giderilmesiyle ham saflığı iyileştiren bazı adsorbentlerin kullanılmasını gerektirir, sonuçta saflık ve verim artar ve aynı zamanda nihai paklitaksel ürünlerin maliyeti düşer. Bu çalışmada sentezlediğimiz adsorbanlar paklitakselin saflaştırılmasında kullanılmak üzere etkileri incelenmiştir.Öğe Pre-purification of an Anticancer Drug (Paclitaxel) Obtained from Nut Husks(Asian Network Scientific Information-Ansinet, 2018) Oğuzkan, Sibel Bayıl; Karagül, Bora; Uzun, Ayşe; Güler, Özen Özensoy; Uğraş, Halil İbrahimBackground and Objective: Hazelnut husk is known to contain taxanes, including paclitaxel. There are many methods for purifying paclitaxel, which is sold under the commercial brand name Taxol and is used as a chemotherapy medication. In this study, the effect of precipitation on the purity and yield of taxanes in the purification process of some taxane compounds from hazelnut husk was investigated by using different solvents. Materials and Methods: Collected, dried and milled samples of hazelnut husk were treated with methanol (1:15 g mL(-1)) at room temperature for 72 h in order to obtain extracts. The extraction process was repeated 20 times to achieve the desired concentrated stock solution. Each 1 mL sample taken from this stock solution was treated with four different solvents with various quantities of binary mixtures (1:5, 1:10 and 1:20) and then analyzed using HPLC (High-Performance Liquid Chromatography) following filtration. Results: The HPLC was used to determine both purity and recovery yield in the stock solution before and after the analysis. Baccatin III has the greatest purity among the paclitaxel derivatives as 10-Deacetylbaccatin III, baccatin III, cephalomannine and paclitaxel, that were evaluated in the present study. Conclusion: Thus, the effects of precipitation from extracts containing taxane compounds derived from the hazelnut husk were determined in the pre-chromatographic purification processes.Öğe Zenginleştirilmiş glisirizin ekstresi eldesi ve saflaştırılması(Düzce Üniversitesi, 2023) Karagül, Bora; Uğraş, Halil İbrahimGlisirizin, meyan kökü bitkisinin en önemli etken maddesidir. Bu tez çalışması glisirizin eldesi ve saflaştırılması için metot geliştirilmesi üzerinedir. Bu kapsamda meyan kökü bitkisinden elde edilen ekstraktlar için ekstraksiyon metodu belirlenmiş ve ardışık saflaştırma basamaklarından sonra flash kromatografi cihazı ile fraksiyonlarına ayrılması gerçekleştirilmiştir. Meyan kökü ekstraksiyonlarında en etkin değerlerin alkol/su karışımlarında olduğu tespit edilmiştir. Tercih edilen alkol çözücüleri etanol ve metanol'dur. Ekstraksiyon işlemlerini sırasıyla adsorban uygulaması ve asidik-bazik ortamda çöktürme işlemleri uygulanarak glisirizinin amonyum tuzu formunda eldesi sağlanmıştır. Flash kromatografi işlemleri uygulanarak saflaştırma basamakları gerçekleştirilmiş olup zenginleştirilmiş glisirizin amonyum tuzu elde edilmiştir. Elde edilen glisirizin amonyum tuzu (amonyum glisirizat) yapı tayini için LC-MS-MS, HPLC ve NMR analizleri ile desteklenmiştir. Ayrıca glisirizin amonyum tuzunun sitotoksisite çalışmaları gerçekleştirilmiş ve ticari glisirizin standardı ile karşılaştırılmıştır. Elde edilen ürünün toksisite göstermediği belirlenmiştir.
