Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
Browse
4 results
Search Results
Master Thesis Antimicrobial, Antioxidant, Antiproliferative and Cytotoxic Activities of Aronia Fruit Extract(01. Izmir Institute of Technology, 2023) Tanağardı, Dilaranur; Baysal, Ayşe Handan; Sezgin, EfeAronia melanocarpa contains high amounts of phenolic compounds, especially anthocyanins. Because of its high chemical content and significant antioxidant action, this food is known as a functional food, and its use is spreading worldwide. Within the scope of this thesis research, studies were carried out on Aronia melanocarpa dry extract and liquid extract. For these purposes, chromatographic and chemical profile were determined in detail by HPLC (High-Pressure Liquid Chromatography), Fourier-Transform Infrared Spectroscopy (FTIR) and Q-TOFF- MS (Quadrupole Time of Flight Mass Spectrometry), and significant bioactive were determined. Spectroscopic methods were used to characterize phenolic, anthocyanin, and flavonoid components. Aronia melanocarpa dry and liquid extracts were tested for antioxidant activity using DPPH and ABTS methods. The antioxidant potential of the Aronia melanocarpa dry and liquid extracts studied is high. To test the antiproliferative and cytotoxic effects, cytotoxic studies were performed on the CaCo2 cell line. Cell migration was also studied in HUVEC and HaCat cell lines. The antimicrobial activity of Aronia melanocarpa dry extract and liquid extract was tested against Saccharomyces cerevisiae, a yeast species, and bacterial strains of Staphylococcus aureus, Escherichia coli O157:H7, Salmonella Typhimurium. The extracts analyzed showed an antimicrobial effect on the tested bacteria at different concentrations. The results obtained in this study emphasize that the tested Aronia melanocarpa dry extract and liquid extract have antimicrobial properties. Chromatographic, chemical, and cytological data reveal that Aronia melanocarpa liquid and dry extracts can be used as antioxidative and antiproliferative products as food supplements in the health field.Master Thesis The Effects of Naphthoquinones Isolated From Onosma Species on Dna Topoisomerases and Their Cytotoxic Properties(Izmir Institute of Technology, 2018) Güzel, Özge; Bedir, Erdal; Bedir, Erdal; Zencir, SevilOnosma L. genus (Boraginaceae) comprises of 230 species that is represented by 102 species and 108 taxa in the flora of Turkey. As 50% of the genus is endemic, Anatolia can be considered as the gene center of Onosma species. Phytochemical investigations performed on Onosma genus have led to the identification of various naphtoquinones, alkaloids and phenolic constituents. Biological activity studies on naphthoquinones demonstrated antimicrobial and wound-healing properties as well as cytotoxicity. In this thesis, Onosma taurica var. taurica and O. mollis were taken into cytotoxic activity-guided isolation studies, by MTT using seven human cancer cell lines (DU145, Capan-1, HCC-1937, MCF-7, HeLa, HEPG2, A-459) and a normal cell line (MRC-5), to isolate their bioactive compounds. Additionally, the isolation studies were guided by enzyme inhibition tests towards human Topoisomerases I and II. Six compounds were isolated using chromatographic methods, and the structures of the five of them were elucidated by spectral methods, (1D-, 2D NMR and HR-ESI-MS) as acetylshikonin, shikonin, β-hydroxyisovalerylshikonin, β,β-dimethylacrylshikonin and deoxyshikonin. The isolated compounds showed prominent cytotoxicity with IC50 values ranging from 1.83 to 25 M. β,β-dimethylacrylshikonin was found to be the most cytotoxic compound (IC50: 1.84 μM versus HCC-1937), whereas β-hydroxyisovalerylshikonin on Topoisomerase I and II (each at 25 M dose) exhibited strong inhibitory effects.Master Thesis Investigation of Anticancer Properties of the Novel Synthesixed Pyrrole Derivatives as Potential Tyrosine Kinase Inhibitors(Izmir Institute of Technology, 2017) Kaya, Meltem; Şanlı Mohamed, GülşahIn cancer treatment, chemotherapy has some serious side effects, because it targets active cells which might not be cancer cells. Mouth, hair, nail, bone marrow cells are some examples of active cells. For the reason that chemotherapy has side effects, targeted therapy become more important. Tyrosine kinases are most interested target, because they are necessary for cell growth and metastasis. Active form of tyrosine kinases can cause tumour growth and proliferation, angiogenesis, metastasis and antiapoptotic effects. Based on these vital role of tyrosine kinases, they became more important target in cancer treatment. Pyrrole derivatives have been used chemotherapy drugs for years. Semaxanib and Sunitinib, indole derivatives, are tyrosine kinase inhibitors. The main purpose of this research is to investigate the biologic activities of novel synthesized seven pyrrole derivatives, their activities on migration, apoptosis, cell cycle, and mTOR downstream as a potential tyrosine kinase inhibitor. The results of this research proved that these seven compounds have toxicity on HeLa cells with the IC50 values of 140.60 μM, 382.82 μM, 366.44 μM, 542.00 μM, 255.86 μM, 148.59 μM, 171.40 μM, respectively, but toxicity effects of drugs do not depend on apoptosis mechanism. Beside this, D1 and D3 were able to effect cell cycle by arresting at S phase for D1 and G1 phase for D3. It was demonstrated that D1 and D3 inhibited cell migration. And this inhibition was reported as in a relation with overexpression of p- 4EBP1, inhibition of p-p70S6K (Thr) and p-p70S6K (Shr) proteins. Considering all results, D1 and D3 might be potent inhibitory of metastasis of HeLa cells with respect to its effect on cell cycle, migration, p-4EBP1, p-p70S6K (Ser), and p-p70S6K (Thr) protein levels.Master Thesis Antiproliferative Properties of 2'-alkoxymethyl Substituted Klavuzon Derivatives(Izmir Institute of Technology, 2017) Yıldız, Mehmet Salih; Pesen Okvur, Devrim; Çağır, Ali; Çağır, Ali; Pesen Okvur, DevrimOne of the main objectives of studies on anticancer agents is that the agent is expected to show a high cytotoxic activity on cancer cells and show a less cytotoxic effect on the contrary in healthy cells or never show cytotoxic activity. (R)- goniothalamin, isolated from the Goniothalamus plant, is a styryl lactone and has been found to have a selective antiproliferative property on cancer cells in studies conducted. The Michael acceptor feature in the structure of goniothalamin is thought to be covalently bonded to the nucleophilic side chains of the enzymes and show activity in this way. In previous studies, it has been shown that 1-naphthyl substituted 5,6-dihydro- 2H-pyran-2-one derivatives and 4'-methyl klavuzon derivatives exhibit higher cytotoxic activity on cancer cells than goniothalamin. In this study, antiproliferative properties of newly synthesized 2'-alkoxymethyl substituted klavuzon derivatives have been examined and MIA PaCa-2 pancreatic cancer cell lines and HPDEC pancreatic healthy cell lines were used. MTT cell viability tests were performed at the first step of this study. As a result of this study, it has been observed that the 2'-isobutoxymethylklavuzon derivative has selective cytotoxic activity on the MIA PaCa-2 cell line. It showed activity at lower concentrations than goniothalamin. Cytotoxic activities of the compounds are associated with the size of the R group at position 2’-. Methoxymethyl substituted the worst selective activity among these compounds whereas isobutoxy derivative the best selective one. In the second stage of the study, the inhibition on topoisomerase I enzyme was studied. The 2'-alkoxymethyl klavuzon derivatives were found to have Topo I enzyme inhibition properties depending on concentration and time manner. The study continued with choices methoxy and isobutoxy derivatives and these two compounds caused an arrest at G1 phase and DNA damage. Also, isobutoxy derivative induced apoptosis in the MIA PaCa-2 pancreatic cancer cell lines.