Akademik Veri Yönetim Sistemi
Tezin Türü: Doktora
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye
Tezin Onay Tarihi: 2013
Öğrenci: NİZAMETTİN ÖZDOĞAN
Danışman: NURSEN ÇORUH
Özet:The genus Rosa, including about 100 species, is found to have a wide distribution throughout Europe, Asia, the Middle East and North America. Rosa heckeliana being a member of Rosa genus has been frequently used in folk medicine. Medicinal plants used in folk medicine are found to reveal their therapeutic effect due to their high content of phenolic compounds. These phenolic compounds contained in Rosacea families are located in their fruits and roots, most abundantly. This study was designed to determine the anti-oxidative and anti-proliferative properties of the roots of R. heckeliana. Roots of the plant were extracted crudely in methanol. The polyphenolic compounds of the crude extract were concentrated and separated by using bioactivity guided solvent-solvent fractionation process. All the fractions and the crude extract were subjected to antioxidant activity assays. Eventually, ethyl acetate fraction, among the others, has been found to expose the highest antioxidant properties. Therefore, the ethyl acetate fraction was further carried out for quantitative and qualitative analyses to reveal its phenolic components. Main phenolic compounds in the ethyl acetate fraction were purified by simple chromatographic methods using “Silica gel 60” and “Sephadex LH-20”. There were three major compounds isolated, they were also identified and characterized using NMR (Carbon and Proton) and HR-MS techniques. These three compounds found in the ethyl acetate fraction, in major amounts, were namely catechin, caffeic acid and ellagic acid. In the same fraction, there were also other phenolic compounds present in minor amounts, they were only subjected to identification through spectroscopic and chromatographic methods (RP-HPLC, UV-Vis spectroscopy). Identifiable compounds were epicatechin, p-coumaric acid, scopoletin and quercetin, and their structures were also confirmed by HR-MS technique. Additionally, the anti-proliferative properties of the roots of Rosa heckeliana were examined by using XTT method. Crude extract, ethyl acetate fraction, and the isolated major phenolic components as well as matching standard compounds were all compared for their cytotoxicity on breast cancer cell lines; MCF-7 and MDA-231. The isolated major phenolic compounds were demonstrating moderate cytotoxicity, while the crude extract and ethyl acetate fraction verified only minimal cytotoxicity.