Köksal, Ekrem; Altin, Sevgi

T his study evaluated the total phenolic and flavonoid material content as well as the antioxidant, antibacterial, and antic - holinesterase activities of extracts prepared from the endemic Glaucium cappadocicum plant. The extracts' antioxidant properties were assessed using the DPPH and FRAP methods, their antibacterial effects were assessed using the disk diffu - sion method on Gram positive and Gram negative bacteria, and their ability to inhibit cholinesterase activity was assessed using the Ellman method. In all biological activity assays, the alkaloid extract had the maximum activity. Especially in enzyme inhibition studies, alkaloid extract showed stronger inhibition than the standard inhibitor tacrine. These findings are the first report showing that high concentrations of compounds with antioxidant, anti-acetylcholinesterase, and antibacterial activity can be found in extracts from Glaucium cappadocicum.

Taşkın Kafa, Ayşe Hümeyra; Cihan, Arzu Coleri; Cankaya, Murat; Kuzucu, Mehmet

In this study, the cloning, purification and initial characterization of carbonic anhydrase (DrCA) enzyme which we consider to be important in the resistance physiology from extremely radioresistant bacteria Deinococcus radiodurans is performed. In addition, the effect of increased gamma irradiation doses on pH-related DrCA enzyme activity was determined. DrCA activity after radiation treatment showed that the activity continuously increased by 6 fold, up to the first 800 Gy, which a decrease in activity was observed thereafter. The maximum $CO_2$ hydration activity for DrCA enzyme was observed at pH 7.0 and 40°C. DrCA enzyme, homo-dimer complex, is slightly thermostable. The activity of DrCA was significantly enhanced by several metal ions, especially $Zn^{2+}$, which resulted in 5-fold increases of $CO_2$ hydration activity. Also sulfonamide showed inhibitory effect on the pure enzyme. The apparent Km and Vmax for $CO_2$ as substrate were 8.4 mM and 637 WAU/mg for DrCA respectively. The $CO_2$ hydration assay demonstrated that the specific activity of purified recombinant enzymes (DrCA) was significantly high.

Kuzucu, Mehmet; Cankaya, Murat; Ozgur, Aykut; Çetin, Ahmet

HER2 positive breast cancer is one of the biggest health problems in the world, causing millions of deaths every year. Drugcombination modeling studies are extensively evaluated in treating many diseases. Pharmacological studies over the lasthalf-century have shown that gambogic acid has potent anti-tumor activity against many types of cancer, including breast cancer.In this study, we examined the synergistic anticancer effect of gambogic acid and trastuzumab in HER2 positive breast cancer cellline (MDA-MB-453). In-vitro synergistic and antiproliferative effects of trastuzumab plus gambogic acid studies were determinedwith XTT method and the combination index (CI) values of the trastuzumab and gambogic acid combination were calculated byCompuSyn software. To determine molecular mechanisms of the trastuzumab and gambogic acid combination in MDA-MB-453cells, the differences of gene and protein expression levels of HER2, caspase-9 and Bax were analyzed with using RT-qPCR andELISA techniques. The combination of 50 μg/ml trastuzumab and 5 μM gambogic acid showed the best synergistic effect at 24h incubation in MDA-MB-453 cells according to the in-vitro cell proliferation, RT-qPCR and ELISA test. Gambogic acid effectson HER2 positive breast cancer cell line shows its potential as natural compound to inhibit breast cancer cell proliferation incombination with trastuzumab.

Solakyildirim, Kemal

Punica granatum L., commonly known as pomegranate, has a good source of bioactive polyphenolic compounds that has been widely used as a traditional Chinese herbal medicine owing to their important biological properties including cardiovascular disease, arthritis, diabetes, and cancer. Commercial pomegranate juice is generally obtained via pressing whole pomegranate and its peels. Then, the most abundant ingredient, punicalagin, can be extracted into the juice. Ho-wever, punicalagin levels may vary in commercial pomegranate juice and it can range from 0.017 to 2 g/L. In this study, we analyzed punicalagin content from six different brands of pomegranate juices by using UPLC-MS method. First, punicalagin standards were prepared from 50 μM to 5 μM in buffer A (0.1% formic acid in water) and standard calibration curve was created. After that, three mass tune parameters including ionization voltage, desolvation temperature and source tempera-ture of ESI source were optimized to obtain better peak shapes and correct quantification of the α- and β- isomer peaks of punicalagin. After analysis of six different brands of pomegranate juices, it was seen that punicalagin levels from different juice samples varied from 0.007 to 0.3 g/L.

Özbek, Mehmet Ufuk; Yüzbaşıoğlu, Sırrı; Kandemir, Ali; Altınözlü, Haşim

This research was carried out in Kemaliye district which about 158 km south-west of Erzincan province. 1800 plant specimens were collected from the area between 2005-2007. Identification of the specimens revealed the presence of 640 taxa belonging to 318 genera in 80 families. Cryptogamae includes 4, Spermatophyta includes 636 taxa (Gymnospermae 3, and Angiospermae 633 taxa). 36 taxa are new records for B7 square. A total of 118 taxa determined in the research area (18,43%) are endemic for Turkey. The scattering ratios of the taxa for the phytogeographical regions are as follows: Irano-Turanian elements are 252 taxa (39,37%), Mediterranean elements are 34 taxa (5,31%), Euro.-Sib. elements are 32 taxa (5%), widespread or other taxa which their regions unclarified are 322 (50,31%).

Kol, Özlem Gürsoy; Albayrak, Önder; Alkan, Muzaffer; Yüksek, Haydar; Manap, Sevda; Kardaş, Faruk; Beytur, Murat

In the present study, 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (1) reacted with 3-ethoxy-2-(4- nitrobenzoxy)-benzaldehyde (2) to afford 2-ethoxy-6-[(3-alkyl/aryl-4,5-dihydro-1H-1,2,4-triazol-5-one-4-yl) iminomethyl]phenyl 4-nitrobenzoates (3). The structures of new nine compounds were established from the elemental analyses, IR, 1 H NMR and 13C NMR spectral data. The synthesized compounds were analyzed for their in vitro potential antioxidant activities in three different methods. In addition, these new compounds were screened for their antimicrobial activities.

Kuzucu, Mehmet; Çankaya, Murat; Tuğral Kaplan, Sibel; Çoban, Taha Abdullkadir; Dilek, Esra; Aktaş, Nurdagül

In the treatment of heart disorders, metoprolol tartrates and digoxin drugs which act by way of blood are used widely. Being vital of using these drug substances, investigation of inhibitory effect on the activities of enzymes in the blood reveals the importance of this work. Aim of this study to investigate effects of metoprolol tartrate and digoxin on human erythrocyte carbonic anhydrase I isoenzyme in vitro conditions. CA-I isoenzyme from human blood has been purified using Sepharose-4B-l-tyrosine-sulfanilamide affinity chromatography method. The enzyme was purified ~116-fold with a yield of 62%. At the end of inhibition studies two substances were showed uncompetitive inhibition. Ki values were determined metoprolol tartrate 5.49±1.86 mM and digoxin 0.0914±0.0062 mM.

Tohma, Hatice; Işık, Mesut; Köksal, Ekrem; Dikici, Emrah

Plants generate secondary metabolites, which could be used as novel therapeutic compounds. These compounds are well known for their beneficial effects on human health. Thus, it is important to evaluate total phenolic and flavonoid contents as well as antioxidant activities of different plants. The present study was conducted to determine the total phenolic/flavonoid content and antioxidant activity of ethanol extract prepared from leaves of Phlomis pungens L. The total phenolic content of the ethanol extract of the sample were determined using the Folin-Ciocalteu reagent. Antioxidant activity of Phlomis pungens L. was determined using different in vitro experimental models, which include DPPH, FRAP, CUPRAC and potassium thiocyanate method. Total phenolic and flavonoid contents of Phlomis pungens L. were found to be 68.4 mg GAE/g and 4.9 mg QE/g, respectively. Antioxidant activity of the sample was comparable to commercial antioxidant standards (BHT, - tocopherol and trolox). The results showed that Phlomis pungens L has moderate free radical scavenging and reducing capacity. Overall, this study discovers total phenolic and flavonoid content as well as antioxidant properties of Phlomis pungens L

Olgun, Abdullah; Köksal, Zeynep; Çoban, Taha Abdulkadir

Endoplasmic reticulum (ER) stress is involved in many diseases including diabetes, cancer and aging. Tauroursodeoxycholic acid (TUDCA) is a chemical chaperone that reduces ER stress. Caenorhabditis elegans (C. elegans), a widely used model organism in aging studies, also suffers from ER stress. In this study, we tested the effect of TUDCA on C. elegans life span with the aim to decipher the contribution of ER stress on C. elegans aging. We tested TUDCA at the concentrations of 0.625, 1.25, 2.5, 3.75, 5, 7.5, 10, 15 and 20 mM. It showed a negative effect on the life span at all of the tested concentrations except 3.75 mM. At this concentration it had no toxicity nor an effect on longevity. One of the previously reported critical micellar concentrations (CMC) of TUDCA is closer to this concentration. Therefore TUDCA’s mechanism of action could be explained, at least in part, by its micelle formation. It could have exerted negative effects at both lower and higher concentrations than CMC. If it had a positive effect on life span through ameliorating ER stress at the CMC, this could have been neutralized by its partial toxicity. Our results can be helpful in future studies on TUDCA which is a very important and promising therapeutical agent.