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Article Citation - WoS: 14Citation - Scopus: 19Determination of Bacterial Community Structure of Turkish Kefir Beverages Via Metagenomic Approach(Elsevier Sci Ltd, 2022) Yegin, Zeynep; Yurt, Mediha Nur Zafer; Tasbasi, Behiye Busra; Acar, Elif Esma; Altunbas, Osman; Ucak, Samet; Sudagidan, MertBacterial microbiota of industrially produced kefir beverages (n:33) consumed in Turkey was studied using a culture-independent method and a metagenomic approach. DNA extraction from non pre enriched and pre-enriched kefir samples was used for 16S rRNA amplicon sequencing. Kefirs were dominated by Firmicutes, followed by Actinobacteria and Proteobacteria phyla. The most abundant genera in non pre-enriched kefir beverages were Lactococcus followed by Streptococcus, Bifidobacterium, Lactobacillus, and Leuconostoc. Pre-enriched kefirs were dominated by Streptococcus followed by Lactobacillus, Lactococcus, Bifidobacterium, and Leuconostoc at the genus level. Psychroserpens, Desulfonispora, Pediococcus, Micromonospora, Fructobacillus, Mycobacterium, Acetobacter, Pseudopedobacter, and Clostridium XI genera were found only in pre-enriched kefirs. Kefirs displayed pH differences from 4.04 to 4.49 and the acidity was 0.617e0.987. In two samples, the lowest pH values were obtained with abundance of Lactobacillus helveticus and Streptococcus salivarius. This study broadens our viewpoint and strengthens future applications of kefir beverages in industrial and medical fields. (C)& nbsp;2022 Elsevier Ltd. All rights reserved.Article Citation - WoS: 29Citation - Scopus: 40Development of Electrochemical Aptasensors Detecting Phosphate Ions on Tmb Substrate With Epoxy-Based Mesoporous Silica Nanoparticles(Pergamon-elsevier Science Ltd, 2022) Altuner, Elif Esra; Ozalp, Veli Cengiz; Yilmaz, M. Deniz; Sudagidan, Mert; Aygun, Aysenur; Acar, Elif Esma; Sen, FatihThis study, it is aimed to develop an electrochemical aptasensor that can detect phosphate ions using 3.3 & PRIME;5.5 & PRIME; tetramethylbenzidine (TMB). It is based on the principle of converting the binding affinity of the target molecule phosphate ion (PO43-) into an electrochemical signal with specific aptamer sequences for the aptasensor to be developed. The aptamer structure served as a gate for the TMB to be released and was used to trap the TMB molecule in mesoporous silica nanoparticles (MSNPs). The samples for this study were characterized by transmission electron spectroscopy (TEM), Brunner-Emmet-Teller, dynamic light scattering & electrophoretic light scattering, and induction coupled plasma atomic emission spectroscopy. According to TEM analysis, MSNPs have a morphologically hexagonal structure and an average size of 208 nm. In this study, palladium-carbon nano particles (Pd/C NPs) with catalytic reaction were used as an alternative to the biologically used horseradish peroxidase (HRP) enzyme for the release of TMB in the presence of phosphate ions. The limit of detection (LOD) was calculated as 0.983 mu M, the limit of determination (LOQ) was calculated as 3.276 mu M, and the dynamic linear phosphate range was found to be 50-1000 mu M. The most important advantage of this bio-based aptasensor assembly is that it does not contain molecules such as a protein that cannot be stored for a long time at room temperature, so its shelf life is very long compared to similar systems developed with antibodies. The proposed sensor shows good recovery in phosphate ion detection and is considered to have great potential among electrochemical sensors.Article Citation - WoS: 1Citation - Scopus: 1Long-Term Intermittent Caloric Restriction Remodels the Gut Microbiota in Mice Genetically Prone To Breast Cancer(Elsevier Science inc, 2024) Keles, Nazim Arda; Dogan, Soner; Dogan, Aysenur; Sudagidan, Mert; Balci, Tugce Nur; Cetiner, Ozlem; Tuna, Bilge GuvencObjectives: Gut microbiota dysbiosis is among the risk factors for breast cancer development, together with genetic background and dietary habits. However, caloric restriction has been shown to remodel the gut microbiota and slow tumor growth. Here, we investigated whether the gut microbiota mediates the preventive effects of long-term chronic or intermittent caloric restriction on breast cancer predisposition. Methods: 10-week-old transgenic breast cancer-prone mice were randomly assigned to dietary groups (ad libitum, chronic caloric restriction, and intermittent caloric restriction groups) and fed up to week 81. Stool samples were collected at weeks 10 (baseline), 17 (young), 49 (adult), and 81 (old). 16S rRNA gene sequencing was performed to identify the gut microbiota profile of the different groups. In order to investigate the breast cancer gut microbiota profile within genetically predisposed individuals regardless of diet, mammary tumor-bearing mice and mammary tumor-free but genetically prone mice were selected from the ad libitum group (n = 6). Results: Intermittent caloric restriction increased the microbial diversity of adult mice and modified age- related compositional changes. A total of 13 genera were differentially abundant over time. Pathogenic Mycoplasma was enriched in the re-feeding period of the old intermittent caloric restriction group compared with baseline. Furthermore, mammary tumor-free mice showed shared gut microbiota characteristics with mammary tumor-bearing mice, suggesting an early link between genetic predisposition, gut microbiota, and breast cancer development. Conclusions: Our study revealed the role of gut microbes in the preventive effects of caloric restriction against breast cancer development, implying the significance of diet and microbiome interplay. (c) 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article Citation - WoS: 7Citation - Scopus: 7Surface Plasmon Resonance Aptasensor for Soluble Icam-1 Protein in Blood Samples(Royal Soc Chemistry, 2022) Dursun, Ali Dogan; Dogan, Soner; Kavruk, Murat; Tasbasi, B. Busra; Sudagidan, Mert; Yilmaz, M. Deniz; Tuna, Bilge G.Intercellular Adhesion Molecule-1 (ICAM-1) is considered to be a cancer biomarker in the assessment of metastatic potential in patients and an early indicator of atherosclerosis. A labelless biosensor based on the surface plasmon resonance (SPR) signal from the specific affinity interaction of an aptamer and a soluble ICAM-1 protein was developed for blood samples. The developed aptasensor provided real-time information on the concentration of the ICAM-1 protein in blood when integrated to a purification step based on a magnetic pull-down separation. The SPR aptasensor was highly specific with a limit of detection of 1.4/0.2 ng ml(-1), which was achieved through aptamer-functionalized silica-coated magnetic nanoparticles.Article Citation - WoS: 17Citation - Scopus: 19Bacterial Surface, Biofilm and Virulence Properties of listeriamonocytogenes Strains Isolated From Smoked Salmon and Fish Food Contact Surfaces(Elsevier, 2021) Sudagidan, Mert; Ozalp, Veli Cengiz; Ozturk, Orhan; Yurt, Mediha Nur Zafer; Yavuz, Orhan; Tasbasi, Behiye Busra; Aydin, AliBiofilm formation is one of the defense mechanisms of bacteria against disinfectants and antimicrobials. The aim of this study was to determine biofilm-forming L.monocytogenes from fish processing and salmon surfaces. Biofilm formation at 15, 25, 37, and 40 degrees C from 1 to 6-days period, adhesion to glass, polypropylene and stainless-steel surfaces, bacterial surface charge and hydrophobicity was determined. Adhesion behavior of the strains was evaluated using Surface Plasmon Resonance (SPR) technique. Totally 32 L.monocytogenes strains belonging to serogroups IIa (n:17), IIc(n:14) and IVb(n:1) were detected from 1320 swabs and 16 smoked salmons. Biofilm formation tests revealed that 21 strains form biofilm on microplate by increasing time and temperature. Although all strains strongly formed biofilm on glass surfaces, two strains slightly adhered polypropylene surfaces. High surface roughness of stainless-steel FeCrNi alloy (Ra = 4.15 nm) and CoCrMo alloy (Ra = 10.75 nm) increased biofilm formation of L.monocytogenes on stainless-steel surfaces. Zeta potential results showed that non-biofilm formers were more negatively charged after 6-days and hydrophobicity couldn't give a distinct distribution among biofilm formers and non-formers. SPR analysis method was evaluated to distinguish biofilm formers to adhere SPR gold chip surfaces. PCR results revealed that all strains were positive for hylA, iap, actA, plcA, plcB, fri, flaA, inlA, inlB, inlC, inlJ, and lmo1386 genes. Additionally, all strains were susceptible to penicillin, ampicillin, meropenem, erythromycin and trimethoprim-sulfamethoxazole. Biofilm-forming, virulence properties of L. monocytogenes strains isolated from fish processing surfaces and smoked salmons were evaluated and SPR was used to differentiate biofilm formers as a sensitive technique for biofilm studies.Article Citation - WoS: 16Citation - Scopus: 16Targeted mesoporous silica nanoparticles for improved inhibition of disinfectant resistant Listeria monocytogenes and lower environmental pollution(Elsevier, 2021) Sudagidan, Mert; Yildiz, Gulsah; Onen, Selin; Al, Rabia; Temiz, S. Sevval Nur; Yurt, Mediha Nur Zafer; Ozalp, Veli C.Benzalkonium chloride (BAC) is a common ingredient of disinfectants used for industrial, medical, food safety and domestic applications. It is a common pollutant detected in surface and wastewaters to induce adverse effects on Human health as well as aquatic and terrestrial life forms. Since disinfectant use is essential in combatting against microorganisms, the best approach to reduce ecotoxicity level is to restrict BAC use. We report here that encapsulation of BAC in mesoporous silica nanoparticles can provide an efficient strategy for inhibition of mi-crobial activity with lower than usual concentrations of disinfectants. As a proof-of-concept, Listeria mono-cytogenes was evaluated for minimum inhibitory concentration (MIC) of nanomaterial encapsulated BAC. Aptamer molecular gate structures provided a specific targeting of the disinfectant to Listeria cells, leading to high BAC concentrations around bacterial cells, but significantly reduced amounts in total. This strategy allowed to inhibition of BAC resistant Listeria strains with 8 times less the usual disinfectant dose. BAC encapsulated and aptamer functionalized silica nanoparticles (AptBACNP) effectively killed only target bacteria L. monocytogenes, but not the non-target cells, Staphylococcus aureus or Escherichia coli. AptBACNP was not cytotoxic to Human cells as determined by in vitro viability assays.Article Citation - Scopus: 1An Investigation on the Dna Binding Activities of Melamine, Cyanuric Acid and Uric Acid(Editura Acad Romane, 2021) Senol, Ali; Devrim, Alparslan Kadir; Sudagidan, Mert; Ozalp, Veli CengizMelamine can be added to various foods such as milk, milk powder, baby food, pet, and livestock feed for cheating purposes due to its high nitrogen content. Regarding its usage in food products, there is a need to investigate its possible interactions with DNA. Thus, this study aimed to investigate the interactions of melamine and its metabolized products, cyanuric acid and uric acid with genomic DNA, isolated from eukaryotic (calf thymus) and prokaryotic (Staphylococcus aureus) sources. UV-absorbance spectrophotometry, fluorescence spectrophotometry, and agarose gel electrophoresis techniques were used to evaluate these interactions. The five different concentrations of melamine, cyanuric acid, and uric acid were incubated with fixed DNA concentration and it was determined that the test compounds interacted with the DNA molecules. The data obtained by UV-absorbance and fluorescence spectrophotometry techniques revealed an increase in wave peaks observed with the increasing substance concentration. After the obtained data of the aforementioned techniques were evaluated together, it was concluded that melamine, cyanuric acid, and uric acid bonded to the eukaryotic and prokaryotic genomic DNA materials via groove binding.Article Citation - WoS: 19Citation - Scopus: 19Metagenomic and Chemical Analysis of Tarhana During Traditional Fermentation Process(Elsevier, 2021) Soyucok, Ali; Yurt, Mediha Nur Zafer; Altunbas, Osman; Ozalp, Veli Cengiz; Sudagidan, MertTarhana is one of the favourable traditional fermented food consumed as a soup. Different flour, vegetables, spices and yogurt are main constituents and they compose of microbiota of Tarhana. In this study, bacterial communities in each fermentation process and in their constituents were identified by metagenomic analysis. Also, chemical properties (pH, acidity, salt content and dry matter) were analysed in each step. The results showed that in the dough formation, mainly Lactobacillus, Bacillus, Enterococcus and Streptococcus were present and after Day 4, Clostridium and Bacillus became dominant, after drying Clostridium disappeared and in the final product bacterial communities from Bacillus and Streptococcus genus were observed. Chemical analysis showed that pH decreased from 4.94 to 4.46, acidity increased by time at the beginning of fermentation from 7.5% to 22.5% in first 6 days period, then, became stable at 14% in drying process. Salt content increased by time from 1.74 to 3.08 g salt/100 g Tarhana in first 8 days and in drying process salt content was recorded as 2.81-2.90 and dry matter was obtained as 94 g dry matter/100 g Tarhana in the final product. This study elucidated the effects of ingredients, raw materials and how microbiota and chemical properties changes during fermentation steps of home-made traditional Tarhana production and thus preparation methods could be developed to obtain standardized Tarhana products for industrial production in future.Article Citation - WoS: 5Citation - Scopus: 6Bacterial and Fungal Microbiota of Mould-Ripened Cheese Produced in Konya(Wiley, 2023) Yurt, Mediha Nur Zafer; Omeroglu, Esra Ersoy; Tasbasi, Behiye Busra; Acar, Elif Esma; Altunbas, Osman; Ozalp, Veli Cengiz; Sudagidan, MertBacterial and fungal diversities of 24 mould-ripened cheeses originating from Konya-Turkiye were examined by metagenomic analysis. Firmicutes phylum, Enterococcus, Clostridium sensu stricto and Lactobacillus (Levilactobacillus) genera were the dominant bacteria. Ascomycota phylum and Penicillium and Pichia genera and Penicillium roqueforti and Pichia membranifaciens species were dominant fungi. Enterococcus faecium (n = 30) and Enterococcus faecalis (n = 6) were identified, and all strains were susceptible to penicillin, ampicillin, vancomycin, teicoplanin, chloramphenicol and linezolid. The highest resistance (n = 14) was against rifampin. Tetracycline resistance was determined in two strains. Biofilm-forming ability was found in nine E. faecium and 1 E. faecalis. E. faecium strains revealed 40-88.9%, and E. faecalis showed 59.2-100% homology by pulsed field gel electrophoresis.Article Citation - WoS: 2Citation - Scopus: 2A Metagenomic Survey of Bacterial Communities From Kurut: the Fermented Cow Milk in Kyrgyzstan(Wiley-v C H verlag Gmbh, 2024) Yegin, Zeynep; Mamatova, Zhanylbubu; Yurt, Mediha Nur Zafer; Tasbasi, Behiye Busra; Acar, Elif Esma; Ucak, Samet; Sudagidan, MertKurut is a traditional dry dairy product mostly consumed in Central Asia. In this study, the distribution of the dominant bacteria present in kurut samples (n=84) originated from seven (Chuy, Issyk-Kul, Talas, Naryn, Jalal-Abad, Osh, and Batken) regions in Kyrgyzstan were analyzed with Illumina iSeq100 platform. The dominant phylum detected was Firmicutes followed by Proteobacteria, Actinobacteria, Cyanobacteria/Chloroplast, and Tenericutes. The most abundant family detected was Lactobacillaceae followed by Streptococcaceae, Enterococcaceae, Chloroplast, and Leuconostocaceae. At the genus level, Lactobacillus was the predominant one in samples and Streptococcus, Enterococcus, Lactococcus, and Streptophyta followed this. Further comprehensive characterization analyses in kurut samples may have potential applications both in industrial starter culture developments and also future therapeutic approaches based on potential strains with probiotic properties. image
