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Öğe Chemical composition and in vitro antimicrobial and antioxidant activities of the essential oil of Nepeta nuda L. subsp Albiflora (Boiss.) gams(ACADEMIC JOURNALS, 2009) Alim, Ahmet; Goze, Ismihan; Cetin, Ali; Atas, Ahmet Duran; Cetinus, Senay Akkus; Vural, NiluferThe chemical composition of Nepata nuda essential oil was hydrodistilled and characterized by gas chromatography-mass spectrometry (GC-MS) and altogether 24 components were detected. The main constituents were trans-caryophyllene (23.9%), isopulegone (12.6%), cis-sabinol (10.1%), and beta-pinene (10.0%). Antimicrobial activity of the oil against Gram-positive and -negative bacteria and fungus, was determined by the disc diffusion assay. The oil showed antibacterial activity against Klebsiella pneumoniae and Salmonella typhi. The antioxidant activity of the essential oil was investigated using 2,2-diphenylpicryl-hydrazyl (DPPH) radical scavenging assay and the -carotene-linoleic acid test. butylated hydroxytoluene (BHT) was employed as a positive control. The essential oil of N. nuda showed weak antioxidant activities. The results suggest that N. nuda essential oil could be a natural antibacterial agent.Öğe Chemical Composition, Antioxidant, Antimicrobial Activities of the Essential Oil of Salvia hypargeia Fisch & Mey.(TAYLOR & FRANCIS LTD, 2011) Atas, Ahmet Duran; Goze, Ismihan; Alim, Ahmet; Cetinus, Senay Akkus; Vural, Nilufer; Goze, H. Murat; Korkoca, HanifiThe aim of this study was to investigate the chemical composition, antioxidant and antimicrobial activities of the essential oil of Salvia hypargeia from Turkey. According to the results of GC-EIMS analysis, the major compounds of the oil were determined as alpha-pinene (15.9 %), beta-pinene (22.3 %), pulegone (13.5 %) and beta-ylangene (17.8 %). Essential oil could not show radical scavenging effect in DPPH system. On the other hand, inhibition capacity of the essential oil against linoleic acid oxidation was measured as 21.0 %. In the case of antimicrobial activity, the most sensitive microorganism was B. subtilis which has the lowest MIC value (35.80 mu g/ml). This is followed by S. aureus and C. diphteriae (8.45 and 14.20 mu g/ml, respectively).Öğe Chemical Composition, Antioxidant, Antimicrobial and Antispasmodic Activities of the Essential Oil of Juniperus excelsa subsp excelsa(TAYLOR & FRANCIS LTD, 2012) Atas, Ahmet Duran; Goze, Ismihan; Alim, Ahmet; Cetinus, Senay Akkus; Durmus, Nedim; Vural, Nilufer; Cakmak, OsmanIn this study, chemical composition, antioxidant, antimicrobial and antiospasmodic activities of the essential oil of the berries Juniperus excelsa Bieb. subsp. excelsa were evaluated in vitro. GC and GS-MS analysis of the oil resulted in the identification of 25 compounds, representing 97.2 % of the oil; alpha-pinene (46.1 %) was the main component. Essential oil showed remarkable antimicrobial activity against the test microorganisms. The sample was also subjected to a screening for its possible antioxidant activity by using 2,2-diphenyl-1- picrylhydrazyl (DPPH) and beta-carotene-linoleic acid assays. It was exhibited moderate antioxidant activity in beta-carotene-linoleic acid test system. In rat ileum, J. excelsa essential oil effect was directly investigated on spontaneous contractions. It has been found that amplitude and frequency did not change significantly at all dose concentrations. Amplitude has been inhibited % 25 and frequency has been inhibited % 20 at 1 mg/mL.Öğe Determination of serum cardiac biomarkers and plasma D-dimer levels in anemic sheep with babesiosis(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2015) Orunc Kilinc, Ozlem; Goz, Yasar; Yuksek, Nazmi; Basbugan, Yildiray; Yilmaz, Ali Bilgin; Atas, Ahmet DuranIn this study, the cardiac effects of anemia and venous thromboembolism (VTE), reportedly caused by the hemolyzed erythrocytes occurring in sheep with babesiosis, were investigated using cardiac markers and D-dimer (DD). The study included 34 sheep: 24 infected Akkaraman sheep (1-3 years old, diagnosed with babesiosis based on clinical and laboratory findings) and a control group of 10 noninfected healthy sheep of the same breed and age. Hematocrit (Hct) levels were measured in blood obtained from both groups. Cardiac troponin I (cTnI), creatine kinase-MB (CK-MB), and aspartate aminotransferase (AST) levels were measured in serum samples. In addition, the levels of DD were also measured in plasma samples. Sheep with babesiosis were subsequently divided into 3 subgroups according to their Hct levels, which ranged from 13.2% to 16.3% in the first group (n = 8), 20.1% to 25.6% in the second group (n = 8), and 27.4% to 30.3% in the third group (n = 8). Evaluations of the measurements of cTnI, CK-MB, and AST levels indicated statistically significant differences between infected and healthy sheep. Statistically significant differences were not found for DD levels between the 2 groups.Öğe Investigation of the in vitro effects of benzimidazol-2-ylidene-based silver-N-heterocyclic carbene complexes on Microsporidia and Leishmania major promastigotes(Elsevier, 2025) Atas, Ahmet Duran; Guelpinar, Derya Guel; Polat, Zuebeyda Akin; Ozdemir, Namik; Sahin, NeslihanIn this study, chloro[1-methallyl-3-(2,3,5,6-tetramethylbenzyl)-5,6-dimethylbenzimidazole-2-ylidene]silver(I) (C24H30AgClN2) (2a), chloro[1-methallyl-3-(2,3,4,5,6-pentamethylbenzyl)-5,6-dimethylbenzimidazole-2ylidene]silver(I) (C25H32AgClN2) (2b), chloro[1-methallyl-3-(naphthylmethyl)benzimidazole-2-ylidene]silver(I) (C24H24AgClN2) (2c) were prepared, and characterized by FT-IR, NMR (1H, 13 C{ 1 H) spectroscopy and elemental analysis. In addition, the structures of 2a and 2b were elucidated by single crystal X-ray diffraction analysis. The study evaluated the cytotoxic potential of benzimidazole-2-ylidene-based silver-NHC complexes in vitro. These complexes were tested for their antimicrosporidial activity using E. intestinalis spores in human renal epithelial cell lines (HEK-293). Similarly, the effect on Leishmania major promastigotes was measured by metabolic activity or cell viability assessed by the tetrazolium reaction. The results of our investigation showed that all the compounds studied exhibited inhibitory effects on the proliferation of both L. major promastigotes and E. intestinalis spores. Complex 2b showed promising potent inhibitory activity to combat microsporidial infections. Complex 2a showed the highest level of activity as a potent anti-Leishmania agent.Öğe Molecular investigation of Anaplasma phagocytophilum and related strains among sheep flocks from different parts of Türkiye; with a note of phylogenetic analyses of Anaplasma phagocytophilum- like 1(Elsevier Sci Ltd, 2024) Erol, Ufuk; Sahin, Omer Faruk; Urhan, Osman Furkan; Atas, Ahmet Duran; Altay, KursatAnaplasma phagocytophilum is a vector-borne zoonotic pathogen and can infect various vertebrate hosts, especially cattle, sheep, goats, horses, and dogs. Molecular-based studies have revealed that the agent has a high genetic diversity and closely related strains circulate in hosts. In this study, 618 sheep blood samples obtained from different geographic regions of Turkiye were researched for A.phagocytophilum and related strains with PCR, RFLP, and DNA sequence analyses. The DNA of these pathogens was detected in 110 (17.79%) samples. RFLP assay showed that all positive samples were infected with A.phagocytophilum-like 1, whereas A.phagocytophilum-like 2 and A.phagocytophilum were not detected. Partial parts of 16 S rRNA gene of seven randomly selected positive samples were sequenced. The phylogenetic analyses of these isolates revealed that at least two A.phagocytophilum-like 1 isolates circulate among hosts in Turkiye and around the world. A.phagocytophilum-related strains have been reported in molecular-based studies over the last few years, but there is a lack of data on the vector competence, epidemiology, clinical symptoms, and genetic diversity of these pathogens. Therefore, large-scale molecular studies are still needed to obtain detailed data on the above-mentioned topics.Öğe Survey of Dirofilaria immitis in dogs from Sivas Province in the Central Anatolia Region of Turkey(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2018) Atas, Ahmet Duran; Altay, Kursat; Alim, Ahmet; Ozkan, ErkanIn this research, we investigate the prevalence of Dirofilaria immitis infection in dogs using microscopical, serological, and molecular methods from the Central Anatolia Region (Sivas) of Turkey and reveal the associated risk factors. Whole blood and serum samples were obtained from 306 dogs older than 7 months. Polymerase chain reaction (PCR) and the modified Knott's method (Knott) were used for detecting the microfilaria and enzyme-linked immunosorbent assay (ELISA) was applied for the presence of D. immitis antigens. The prevalence of D. immitis in dogs was detected as 2.9% (9/306) by PCR and ELISA and as 1.3% (4/306) by Knott. All Knottpositive samples were also found positive by both PCR and ELISA. According to ELISA and PCR results, no statistically significant difference was found between the prevalence in males (4.2%) and females (1.5%); dogs 0.7-2 years old (2.5%), 3-5 years old (2.2%); and more than 6 years old (7.1%); or stray (3.7%) and owned (1.7%) dogs (P > 0.05). One of the PCR products was selected for sequence analyses of the 16S small subunit rRNA gene and the obtained sequence was submitted to GenBank (KJ183078). The 16S rRNA sequence exhibited 100% identity to other D. immitis sequences available in GenBank (FJ799911, FJ799917, FJ799916). This research provides the first data on D. immitis infections in dogs from Sivas Province by using the combined identification techniques.Öğe Survey of Theileria, Babesia and Anaplasma Infections of Cattle and Ticks from Sivas Province of Turkey(2020) Altay, Kürşat; Atas, Ahmet Duran; Ograk, Yusuf Ziya; Özkan, ErkanThis study was carried out to investigate the presence and distribution of Theileria, Babesia and Anaplasmaspecies in cattle and their ticks from Sivas province. A total of 314 EDTA-blood samples and 610 ticks were analysed.A part of 18S and 16SrRNA genes of Theileria/Babesia and Anaplasma species were amplified from the genomicDNAs extracted of the blood samples and tick pools by with polymerase chain reaction (PCR). A total of 14 probes (twocatchall, two genera and ten species-specific) were bound on a membrane and then the PCR products were tested byreverse line blot (RLB) assay. The partial sequences of the 18S and 16S rRNA genes of representative positive sampleswere determined. According to the results of the blood and tick samples analysed by RLB and sequencing, T.buffeli (GenBank accesion number: KJ183080), A. centrale (KJ183082), A. marginale (KJ183083), A. bovis(KJ183084), one Babesia genotype (Babesia sp. Sivas, KJ183081) and one Anaplasma genotype (Anaplasma sp.Sivas, KJ210855) were detected. Babesia sp. Sivas were found to be 99% identical with B. occultans, Babesia sp.Kashi and Babesia sp. Kayseri whereas Anaplasma sp. Sivas were found to be 99% and 98% identical with Anaplasmasp. Clone 7 and A. bovis, respectively. Overall prevalences of Theileria and Anaplasma infections in cattle werefound to be 5.10% and11.15% by RLB, respectively. This study is the first molecular survey on species of Theileria,Babesia and Anaplasma in cattle and ticks from Sivas.Öğe The determination of treatment effect of chitosan oligosaccharide in lambs with experimentally cryptosporidiosis(Elsevier, 2019) Aydogdu, Ugur; Coskun, Alparslan; Atas, Ahmet Duran; Basbug, Onur; Agaoglu, Zahid TevfikIn this study, it was aimed to investigate the efficacy of chitosan oligosaccharide administrations in different doses of experimental infected lambs with Cryptosporidium parvum. 32 male lambs were used in the study and the lambs were divided into 4 groups with 8 lambs in each group. Groups 1, 2 and 3, twice a day, were administered chitosan oligosaccharide at a dose of 100, 500, and 1000 mg/kg for 7 days, respectively, with milk replacer. In group 4, lambs with cryptosporidiosis were subjected to normal feeding as control without drug administration. Clinical examinations of lambs were made before treatment (day 0) and on days 1, 3, 5 and 7 after treatment and 5 ml of blood was collected from vena jugularis for blood analysis of all lambs. Weight changes of lambs were recorded at 0, 7, 14, and 21 days. Stool specimens were collected pre-treatment (day 0) and on days 1, 3, 5, 7, 14 and 21 post-treatment to determine oocyst excretion of lambs with cryptosporidiosis. Lambs with a mean oocyte counts > 10 after stool examination were included to the treatment. Changes in clinical hematology, blood gases and biochemical parameters were observed during the course of treatment, but these changes were limited. Weight loss was observed at 7th day according to 0th day the lambs with experimental cryptosporidiosis but gradually weight increase was observed at 14th and 21st days and these changes were similar in all groups. Oocyst excretion decreased in all groups during treatment. According to 0th day, there was a significant (p < 0.05) decrease in oocyte excretions in the third day in group 1 and 2, and in day 5 in the group 3 and 4. Significant changes (p < 0.05) were observed in oocyst excretions on the third and fifth days among the groups. As a result, in lambs with experimental cryptosporidiosis, chitosan oligosaccharide improved in clinical signs and stool character shorter than the positive control group and the administration of chitosan oligosaccharide at doses of 100, 500 and 1000 mg/kg for 7 days significantly reduced oocyst excretion but not enough to remove cryptosporidiosis completely.Öğe The first evaluation of the in vitro effects of silver(I)-N-heterocyclic carbene complexes on Encephalitozoon intestinalis and Leishmania major promastigotes(Springer, 2024) Atas, Ahmet Duran; Akin-Polat, Zuebeyda; Gulpinar, Derya Gul; Sahin, NeslihanEncephalitozoon intestinalis is an opportunistic microsporidian parasite that primarily infects immunocompromised individuals, such as those with HIV/AIDS or undergoing organ transplantation. Leishmaniasis is responsible for parasitic infections, particularly in developing countries. The disease has not been effectively controlled due to the lack of an effective vaccine and affordable treatment options. Current treatment options for E. intestinalis infection and leishmaniasis are limited and often associated with adverse side effects. There is no previous study in the literature on the antimicrosporidial activities of Ag(I)-N-heterocyclic carbene compounds. In this study, the in vitro antimicrosporidial activities of previously synthesized Ag(I)-N-heterocyclic carbene complexes were evaluated using E. intestinalis spores cultured in human renal epithelial cell lines (HEK-293). Inhibition of microsporidian replication was determined by spore counting. In addition, the effects of the compounds on Leishmania major promastigotes were assessed by measuring metabolic activity or cell viability using a tetrazolium reaction. Statistical analysis was performed to determine significant differences between treated and control groups. Our results showed that the growth of E. intestinalis and L. major promastigotes was inhibited by the tested compounds in a concentration-dependent manner. A significant decrease in parasite viability was observed at the highest concentrations. These results suggest that the compounds have potential anti-microsporidial and anti-leishmanial activity. Further research is required to elucidate the underlying mechanisms of action and to evaluate the efficacy of the compounds in animal models or clinical trials.
