Research Information System
Thesis Type: Doctorate
Institution Of The Thesis: Gazi Üniversitesi, Sağlık Bilimleri Enstitüsü, Turkey
Approval Date: 2017
Student: LEYLA PASAYEVA
Supervisor: OSMAN ÜSTÜN
Abstract:It is known some difficulties of synthetic drugs use in cancer therapy because of side effects and interactions nowadays. On the other hand, because of their wide application, therapeutic efficacy and low toxicity of herbal drugs is more important on anticancer studies and they are on improving. Terpenes are one of the natural compounds have remarkable anticancer activity. The reason of selecting Cousinia species is that they are belonged to Asteraceae family which is rich of terpenoids, never studied for cytotoxic activity and have not been phytochemically analyzed. In this study, preliminary phytochemical analyses were carried out to determine the major active substance groups and plants were found to contain mainly phenolic and steroidal compounds. Then methanol extracts were prepared from species, included this section, and the antioxidant and cytotoxic effects were detected on lung cancer, colon cancer and healthy lung cell lines. More active plants C. stenocephala and C. davisiana were selected as the guide plants. From both plant extracts and sub-extracts were prepared subjected to activity studies. Isolation studies were carried out on dichloromethane (CSD) extract (IC50 = 130 μg / mL on Colo 205 cell line) of C. stenocephala and n-butanol (CDB) extract of C. davisiana plant. As a result, rutin and isorhamnetin 3-O rutinoside isolated from the CDB extract and pseudo-taraxasterol isolated from CDS extract used different chromatographic methods. The compound obtained from the CSD extract was screened for activity and showed no cytotoxic effect. It has been thought that the cytotoxic effect of the plant may be due to the synergistic effect of ψ-taraxasterol which isolated from fraction with myricetin, caffeic acid esters and apigenin 7-apiosylglycoside compounds determined by LC-MS/MS. Compounds obtained from CDB extracts have been reported to be potent natural antioxidant agents as described in literature. Besides, the main methanol extracts were examined in terms of chemical contents with LC-MS/MS and were found to contain mostly caffeic acid and quinic acid derivatives. Although there is no significant difference between the extracts, it has been determined that there is only differences in the amount of the substances.