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    Cytotoxic effect of Cotinus coggygria extract on Hep3B cancer cell line
    (Taylor & Francis Ltd, 2023) Danjolli-Hashani, Dua; Selen-Isbilir, Sebnem
    Cotinus coggygria Scop. is a medicinal plant which contains a variety of precious phytochemical compounds applicable in traditional medicine. The aim of this study is to investigate the cytotoxic effect of Cotinus coggygria extract on Hep3B cancer cells. The cytotoxic effect was measured by MTT assay. Based on IC50 values, the C. coggygria leaf extract showed cytotoxic effect on Hep3B cancer cells, which was found better at 24 h (IC50 = 3.642) then at 48 h (IC50 = 3.956). Also, the dose of C. coggygria extract showed negative correlation (p < 0.05) with cell viability of 24 h and 48 h and positive correlation (p < 0.05) with cytotoxic effect of 24 h and 48 h. The cytotoxic effects were concentration-time dependent. According to our study, C. coggygria extract had protective effect at 24 h on AML12 cell line and cytotoxic effect on the Hep3B cancer cell line, where it indicates that it may have an antitumorigenic effect.
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    Determination of 8-OHGua by LC-MS/MS after Acid Hydrolysis of Oxidative Damaged DNA
    (Iranian Chemical Soc, 2023) Danjolli-Hashani, Dua; Celik, Saffet; Selen-Isbilir, Sebnem
    A variety of influences can cause DNA damage to the genome. The hydroxyl radical attacks the C-8 atom of guanine, forming 8-hydroxyguanine (8-OHGua) or 8-hydroxy-2'-deoxyguanosine (8-OH-2'dG) which are important indicators of oxidative damage on DNA. Determining these damaged base products can be accomplished through measurement by LC-MS/MS after enzymatic hydrolysis or measurement by GC-MS/MS after chemical hydrolysis. In this study, it was aimed to hydrolyze DNA using various strong acids and to measure 8-hydroxyguanine by LC-MS/MS. In the first stage of the study, the nucleoside 8- hydroxy-2'-deoxyguanosine was treated with HCl (2 M and 6 M), TCA (10%), TFA (10%), o-phosphoric acid (2 M), methanesulfonic acid (2 M), and formic acid (80%). The amounts of 8-hydroxyguanine were determined by LC-MS/MS. It has been identified that formic acid with the highest yield (70%) hydrolyzes the beta-glycosidic linkage between the base and the sugar. Subsequently, oxidative damage was induced on calf thymus DNA by producing hydroxyl radicals via the Fenton reaction. The resulting oxidative damaged DNA was hydrolyzed using formic acid. The amount of 8-hydroxyguanine was then determined using LC-MS/MS. Based on the results obtained, it was observed that the acidic hydrolysis applied was effective in breaking the N-glycosidic bond, but not effective in breaking the phosphodiester bond of oxidatively damaged DNA.
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    Effects of Extraction Period on Bioactive Compounds Extracted from Olea Europaea (var. Domat) Leaves by Ultrasound-Assisted Extraction
    (Slovensko Kemijsko Drustvo, 2022) Danjolli-Hashani, Dua; Selen-Isbilir, Sebnem
    In this study, polyphenols from olive leaves (Domat var.) were compared by shaking water bath and ultrasound-assisted extraction to compare the polyphenol contents and antioxidant activity in olive leaves. The effects of the extraction time on the antioxidant activity of olive leaves will be analyzed depending not only on the extraction method but also on the extraction time, due to the extraction yield, antioxidant activity, as well as the type of polyphenols recovered. Objective: To obtain high antioxidant results and to determine the phenolic compounds contained in olive leaf (Domat var.) by LC-MS/MS after ultrasonic water bath and shaking water bath extraction comparison in a shorter time instead of 2 h. Conclusions: The phenolic compounds contained in olive leaf by ultrasound-assisted extraction were higher than water bath extraction. We said that there is no significant difference between the extraction time and TPC and TFC. There was also no relationship between extraction time and DPPH and ABTS EC50 values (p < 0.05), which means that 15 min of sonication can be performed instead of 120 min.