Person: SESAL, NÜZHET CENK
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SESAL
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NÜZHET CENK
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Publication Metadata only Dose-dependent effects of endosulfan and malathion on adult wistar albino rat ovaries(2009) KAYHAN, FİGEN ESİN; Koç N.D., Kayhan F.E., Sesal C., Muşlu M.N.In this sludy, histological effects and malondialdehyde (MDA) levels were investigated by endosulfan and malathion in adult female rat ovaries. An increase of MDA level in rat ovarium tissues due to endosulfan and malathion may be an indicator of the tree radicals occurred during the metabolism and their lipid peroxidative inducing damage. In this study in accordance with the biochemical findings, the study demonstrated that there are pronounced structural defects in histological examinations of ovarian tissues in rats which were administered endosulfan and malathion. It has been observed that the size of ovarian tissues of rats which were administered endosulfan and malalhion in different doses was decreased in various levels. There was a significant decrease healthy follicles and a significant increase atretic follicles in low dose of endosulfan and malathion (11 mg kg-1) treated rats The histologic observations of the ovary revealed the presence of less number of healthy follicles and more number of atretic follicles and corpus Intcums in high dose of endosulfan and malathion (33 mg kg-1} treated rats. Finally, a peroxidative damage occurs inavitably due lo endosulfan and malathion for ovarium tissues. The biochemical results (MDA levels) also showed such a damage, similar with the histological results. © 2009 Asian Network for Scientific Information.Publication Open Access Evaluation of antibacterial potencies of eight lichen extracts against gram-positive moderately halophilic bacteria(2023-01-01) ÇAĞLAYAN, PINAR; BİRBİR, MERAL; SESAL, NÜZHET CENK; Toksoz O., Turkmenoglu I., Berber D., ÇAĞLAYAN P., BİRBİR M., SESAL N. C.The leather sector has global economic importance. Overcoming microbiological problems, especially arising from halophilic bacteria, will greatly reduce product losses. In this study, lichen species including Usnea sp., Platismatia glauca, Ramalina farinacea, Evernia divaricata, Bryoria capillaris, Hypogymnia tubulosa, Pseudevernia furfuracea and Lobaria pulmonaria were examined for their antibacterial efficacies against Staphylococcus saprophyticus subsp. saprophyticus (TR5) and Salinicoccus roseus (KV3) which are proteolytic and lipolytic Gram-positive moderately halophilic bacteria. The extracts of P. glauca, B. capillaris, P. furfuracea and L. pulmonaria had no antibacterial efficacy against the test bacteria. On the other hand, the extracts of H. tubulosa, R. farinacea, Usnea sp. and E. divaricata had considerable antibacterial effect with varying percentages of inhibition. The maximum inhibition ratios at the tested concentrations of 15–240 µg ml–1 for lichen samples of H. tubulosa, R. farinacea, Usnea sp. and E. divaricata were detected as 94.72 ± 0.75%, 76.10 ± 1.85%, 99.36 ± 0.04%, 89.49 ± 2.26% for TR5 and 97.44 ± 0.14%, 95.92 ± 0.29%, 97.97 ± 0.39%, 97.58 ± 0.53% for KV3, respectively. The most remarkable suppression was obtained with Usnea sp. extracts against KV3. These results indicate the need for further studies investigating the applicability of these natural resources to control moderately halophilic bacteria in the preservation of raw hides and skins.Publication Open Access Systematically investigation on the spectral, antioxidant and antibacterial properties of fragrant methyl benzoate esters containing electron withdrawing and electron releasing groups(2023-11-05) SESAL, NÜZHET CENK; ODABAŞ, ZAFER; Alemdar A., Tan B., Toksöz O., Kurtuluş G., Sesal C., ODABAŞ Z.In this study, the effects of electron-withdrawing or electron-releasing groups in methyl benzoate esters, which are widely used in the fragrance industry, on the antioxidant and antibacterial activities of the compounds were investigated. Firstly, methyl benzoates with electron-withdrawing (NO2 and Cl groups) or electron-donating groups (CH3 and OCH3 groups) in the para position, which are commercial compounds, were synthesized, and extensively studied in terms of reaction conditions, and spectral data in their instrumental analysis methods. Then, the synthesized compounds were evaluated for their antioxidant, antibacterial, and cytotoxic activities. Among them, methyl 4-nitrobenzoate exhibited the highest inhibition against Staphylococcus aureus and Pseudomonas aeruginosa. Methyl 4-methoxybenzoate was selected for cytotoxicity evaluation due to its high antioxidant activity, and while the results indicated a dose-dependent decrease in cell viability, lower concentrations may still be considered for cosmetic applications. These findings suggest that antioxidant activity and cytotoxic activity are directly related to the electron density of the molecule. Therefore, this very up-to-date research covers many implications for organic chemistry, medicinal chemistry, biotechnology, and microbiology. Therefore, the results obtained may have great potential to be applied in the cosmetic industry and could be used as exceptionally useful information on alternative raw material selection for researchers in the fragrance industry. These results also suggest that methyl benzoates have potential as lead compounds for the development of novel antioxidant, antibacterial, and cytotoxic agents, but further studies are needed to fully explore their applications in various fields.Publication Open Access Extremophilic Natrinema versiforme Against Pseudomonas aeruginosa Quorum Sensing and Biofilm(FRONTIERS MEDIA SA, 2020-02-06) TOKSOY ÖNER, EBRU; Basaran, Tunahan Irmak; Berber, Didem; Gokalsin, Baris; Tramice, Annabella; Tommonaro, Giuseppina; Abbamondi, Gennaro Roberto; Erginer Haskoylu, Merve; Toksoy oner, Ebru; Iodice, Carmine; Sesal, Nuzhet CenkPseudomonas aeruginosa is an opportunistic pathogen that causes high morbidity and mortality rates due to its biofilm form. Biofilm formation is regulated via quorum sensing (QS) mechanism and provides up to 1000 times more resistance against conventional antibiotics. QS related genes are expressed according to bacterial population density via signal molecules. QS inhibitors (QSIs) from natural sources are widely studied evaluating various extracts from extreme environments. It is suggested that extremely halophilic Archaea may also produce QSI compounds. For this purpose, we tested QS inhibitory potentials of ethyl acetate extracts from cell free supernatants and cells of Natrinema versiforme against QS and biofilm formation of P. aeruginosa. To observe QS inhibition, all extracts were tested on P. aeruginosa lasB-gfp, rhlA-gfp, and pqsA-gfp biosensor strains and biofilm inhibition was studied using P. aeruginosa PAO1. According to our results, QS inhibition ratios of cell free supernatant extract (CFSE) were higher than cell extract (CE) on las system, whereas CE was more effective on rhl system. In addition, anti-biofilm effect of CFSE was higher than CE. Structural analysis revealed that the most abundant compound in the extracts was trans 4-(2-carboxy-vinyl) benzoic acid.Publication Open Access Using proteomics, q-PCR and biochemical methods complementing as a multiapproach to elicit the crucial responses of zebrafish liver exposed to neonicotinoid pesticide(2023-06-01) SESAL, NÜZHET CENK; GÖKALSIN, BARIŞ; KAYHAN, FİGEN ESİN; Kızılkaya Ş., Akpınar G., Sesal N. C., Kasap M., Gökalsın B., Kayhan F. E.Pesticides enter the environment through runoff and leaching and this raises public concern about effects on non-target organisms. Imidacloprid (IMI) a synthetic pesticide, has an unstable half-life, metabolized in minutes to weeks in the water. To evaluate the effects of IMI on the zebrafish liver, we conducted proteomic, molecular and biochemical analysis in a multi-level approach, to highlight the complementary features regarding the results of each method. Adult zebrafish were exposed to 60 mg/L IMI for 48 hours and were evaluated using nLC-MS/MS for proteins, q-PCR analysis for expression of cat, gpx, pxr, ache, along with CAT and AChE enzyme activities and GSH and MDA assays. Based on proteomics, the regulation of antioxidant and immune responses, as well as gene transcription were significant processes affected. Apoptosis and ER stress pathways were upregulated and there was a down-regulation of cat and gpx genes. There was also elevated CAT activity and GSH and decreased MDA. Additionally, elevated AChE activity and up regulation of ache expression was observed. The multi-approach results included regulators of antioxidant, xenobiotic response and neuro-protective related proteins (genes and enzymes), which overall reflected harmful effects of IMI. Consequently, this study highlights the effects of IMI on zebrafish liver and reveals new potential biomarkers. In this respect, evaluated outcomes reveal the complementary features emphasizing the importance of studying chemicals using several methods. Our study provides deeper insights for future work in ecotoxicological studies regarding IMI and contribute to existing toxicity literature.Publication Open Access Infusion or Decoction Extracts ofHelianthus annuusLeaves: Potential Inhibitors for QS system and Biofilm Formation in Pseudomonas aeruginosa(2020-10-05) SESAL, NÜZHET CENK; Arhun Ali BALKAN;Ayla YILDIZ;Didem BERBER;Barış GÖKALSIN;Cenk SESALPseudomonas aeruginosais one of the drug-resistant opportunistic pathogenswith the ability to form biofilm and to produce a number of virulence factors via Quorum Sensing (QS) regulation. Most researchers have focused on QS inhibition to overcome the drug resistance problem.QS inhibitormolecules are investigated from natural resources.In the present study, anti-QS activities of ethyl acetate extracts of decoction and infusion samples from Helianthus annuusleaveswere tested on biosensor strains of P.aeruginosa(lasB-gfp, rhlA-gfp andpqsA-gfp), as well as anti-biofilm activities on PAO1wild type. H.annuusleaf sampleswere firstly infused or decocted and then extracted with ethyl acetate. Theefficacies ofinfusion or decoction extracts were examinedat the concentrationsof 240, 120,and60μg/mlin 96-well microplatesand evaluated in Citation 3 multimode microplate reader (Biotek). The inhibition rates of decoction extracts were recorded as 70.61% for las, 44.09% for rhland 83.77% for pqssystem at 240 μg/ml. The biofilm inhibition percentages of the extracts were determined to be 50.82% (±1.36). Moreover, inhibition rates for infusion extracts were detected as 62.08% for las, 45.15% for rhland 77.79% for pqs, and 53.88% (±3.94) for biofilm formation. In conclusion, the potential efficacies of the extracts of decocted or infused H.annuusleaves were demonstratedon QS system and biofilmformation of P.aeruginosa. However, there is a need for more detailed investigations and determination of the active substances that have QSI and anti-biofilm effect.Publication Open Access Effects of UV-B Radiation on the Performance, Antioxidant Response and Protective Compounds of Hazelnut Pollen(2022-10-01) ÇETİNBAŞ GENÇ, ASLIHAN; SESAL, NÜZHET CENK; ÇETİNBAŞ GENÇ A., Toksoz O., Piccini C., Kilin O., SESAL N. C. , Cai G.Increasing ultraviolet (UV) radiation is expected to become a problem in hazelnut cultivation. The aim of this study is to examine the effects of UV-B on hazelnut pollen. To this end, the pollens were exposed to UV-B for 1, 2, and 3 h at distances of 10, 20, 30, and 40 cm. Groups treated for 2 h at 20 cm and 3 h at 10 and 20 cm were identified as the most affected based on the results of viability, germination, and tube elongation. Further studies on these groups showed that UV-B does not change the DPPH radical scavenging activity for all groups. However, total phenolic compounds decreased after 3 h of treatment at 10 and 20 cm, while total flavonoid compounds decreased after all treatment groups. The UV-B absorbance of cytoplasmic and cell-wall-bound fractions decreased for all groups. The UV-B absorbance of the sporopollenin-derived fraction increased after 2 h of treatment at 20 cm but decreases after treatment for 3 h at 10 and 20 cm. In summary, exposure to UV-B for different times and distances adversely affected pollen grains in terms of pollen viability, germination rate, tube length, and the level of antioxidant molecules and UV-absorbing compounds.Publication Metadata only Lichen secondary metabolite evernic acid as potential quorum sensing inhibitor against Pseudomonas aeruginosa(SPRINGER, 2016) SESAL, NÜZHET CENK; Gokalsin, Baris; Sesal, Nuzhet CenkCystic Fibrosis is a genetic disease and it affects the respiratory and digestive systems. Pseudomonas aeruginosa infections in Cystic Fibrosis are presented as the main cause for high mortality and morbidity rates. Pseudomonas aeruginosa populations can regulate their virulence gene expressions via the bacterial communication system: quorum sensing. Inhibition of quorum sensing by employing quorum sensing inhibitors can leave the bacteria vulnerable. Therefore, determining natural sources to obtain potential quorum sensing inhibitors is essential. Lichens have ethnobotanical value for their medicinal properties and it is possible that their secondary metabolites have quorum sensing inhibitor properties. This study aims to investigate an alternative treatment approach by utilizing lichen secondary metabolite evernic acid to reduce the expressions of Pseudomonas aeruginosa virulence factors by inhibiting quorum sensing. For this purpose, fluorescent monitor strains were utilized for quorum sensing inhibitor screens and quantitative reverse-transcriptase PCR analyses were conducted for comparison. Results indicate that evernic acid is capable of inhibiting Pseudomonas aeruginosa quorum sensing systems.Publication Metadata only Reducing Virulence and Biofilm of Pseudomonas aeruginosa by Potential Quorum Sensing Inhibitor Carotenoid: Zeaxanthin(SPRINGER, 2017) SESAL, NÜZHET CENK; Gokalsin, Baris; Aksoydan, Busecan; Erman, Burak; Sesal, Nuzhet CenkPseudomonas aeruginosa can regulate its virulence gene expressions by using a signal system called quorum sensing. It is known that inhibition of quorum sensing can block biofilm formation and leave the bacteria defenseless. Therefore, it is necessary to determine natural sources to obtain potential quorum sensing inhibitors. This study aims to investigate an alternative treatment approach by utilizing the carotenoid zeaxanthin to reduce the expressions of P. aeruginosa virulence factors through quorum sensing inhibition. The inhibition potential of zeaxanthin was determined by in silico screening from a library of 638 lichen metabolites. Fluorescent monitor strains were utilized for quorum sensing inhibitor screens, and quantitative reverse-transcriptase PCR assay was performed for evaluating gene expression. Results indicate that zeaxanthin is a better inhibitor than the lichen secondary metabolite evernic acid, which was previously shown to be capable of inhibiting P. aeruginosa quorum sensing systems.Publication Metadata only Endolichenic fungi extracts: A promising alternative for ultraviolet protection in cosmetics(2023-07-01) SESAL, NÜZHET CENK; Toksoz O., Hur J., SESAL N. C.Lichen-derived extracts are a potential source for skin health products due to their antioxidant activity that can prevent damage caused by ultraviolet (UV) rays. The slow natural growth and limited reproduction of lichens limit their use. However, endolichenic fungi (ELF) from lichen thalli can serve as a more efficient, rapid, and standardized biological resource for the cosmetic industry. We aimed to investigate the UV protection of Lobaria pulmonaria, Bryoria capillaris, and Usnea sp., and isolated ELF extracts. Total antioxidant, phenolicflavonoid content, sun protection factor (SPF), and tyrosinase inhibitory activities of lichen and ELF extracts were also investigated. As a result, ELF extracts were found to have antioxidant content close to, and in some cases, much higher than lichen species. While SPF values of lichen species varied between 31.45-31.80, results close to lichens were found in the range of 6.54-32.01 values of ELF extracts. Interestingly, lichen extracts did not have tyrosinase inhibitory activity, while some ELF extracts had tyrosinase inhibitory activity in the range of 2.49-38.44. The results of this study suggest that ELF extracts may have the potential to be used as innovative UV protectants in the cosmetic industry.
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