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Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2026/r/gumushane/13767
  Whole-genome characterization of clinical Enterococcus faecalis and Staphylococcus epidermidis Isolates reveals mecA-positive E. faecalis and a shared lnu(A)–rep7a resistance plasmid in Türkiye

  Ejder, Nebahat; Özad Düzgün, Azer

  Background: This study aimed to genomically characterize clinical Enterococcus faecalis and Staphylococcus epidermidis isolates obtained from aspirate and sputum samples at Bayburt State Hospital, focusing on antimicrobial resistance genes, virulence factors, and mobile genetic elements. Methods: Whole-genome sequencing (WGS) was performed on the isolates, and antimicrobial resistance genes, virulence determinants, multilocus sequence types (MLST), plasmid replicons, and mobile genetic elements were identified using bioinformatics tools. Results: The E. faecalis E5 (ST64) isolate, recovered from an aspirate sample, carried multiple antimicrobial resistance genes, including mecA, vanT, erm(B), tet(M), and qacA, along with a diverse virulence gene repertoire (cyl, ebp, ace, and agg), mobile genetic elements (Tn6009, ISL1a3), and four plasmid replicons (rep19C, rep9C, repUS43, and rep7a). The E. faecalis E184 and E187 isolates (ST124), obtained from sputum samples, harbored fewer acquired resistance genes but shared gyrA (T672A) and parC (V307I) mutations associated with fluoroquinolone resistance. The S. epidermidis ST59 isolate carried resistance genes lnu(A), fosB, and qacD, together with the plasmid replicon rep7a and insertion sequence ISSau4. The co-occurrence of lnu(A) and the rep7a plasmid in both species suggests a potential pathway for interspecies transmission of resistance determinants. Conclusions: This study reports the genomic detection of mecA in an E. faecalis isolate from Türkiye based on WGS analysis. However, this finding is based solely on genomic data and lacks phenotypic or experimental validation. The detection of a shared plasmid-associated resistance element (lnu(A)–rep7a) in both E. faecalis and S. epidermidis highlights the potential for interspecies resistance gene flow within the hospital environment.

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• MakaleYalnız künye2026/r/gumushane/13472
  Effects of sunlight ripening process on the biological activities of persimmon (Diospyros kaki L.) peel and pulp extracts

  Kardil, Uğur; Akar, Zeynep; Düzgün, Azer Özad

  The aim of the study was to evaluate the biological properties of the peel and pulp extracts of persimmons, with consideration of the impact of different ripening conditions (B: on-branch ripened and S: sunlight ripened). The data demonstrated that the sunlight ripened persimmon peel (S. peel) extract exhibited a higher total phenolic and flavonoid content, with 157 and 7.3 µg/mL GAE respectively. The S. peel extract exhibited the highest antioxidant activity, exhibiting 1.1578 mg/mL IC50, 54.095 and 0.0262 µM Trolox equivalent (TE)/g fresh weight (FW), as determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging assay, ferric reducing antioxidant power (FRAP) and cupric reducing antioxidant capacity (CUPRAC) respectively. LC-MS/MS analysis revealed that the peel and pulp phenolic composition of persimmon ripening process different conditions changed. The activity of protocatechuic, chlorogenic, caffeic and ferulic acids identified in persimmon extracts was determined by HPLC-DAD-FRAP assay. ICP-OES analysis revealed that potassium exhibited the highest mineral content of persimmon, with values ranging from 575.680 to 2031.360 mg/kg. The S. peel extract was more inhibitory activity against bovine carbonic anhydrase (BCA) and α-glucosidase then other extracts. Moreover, the S. peel extract was found to demonstrate the highest level of antibiofilm activity, reducing the strong biofilm formation capacity of the A. baumannii isolate to negative, both qualitatively and quantitatively. The study suggests that the ripening of persimmon fruit in sunlight may increase biological activity and may be useful in the prevention and treatment of diseases associated with oxidative damage, diabetes and bacterial infections.

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• MakaleAçık Erişim2025/r/gumushane/19721
  Assessment of antioxidant, antimicrobial, antibiofilm, carbonic anhydrase and α-glucosidase inhibitory activities of Alchemilla vulgaris L. extracts

  Düzgün, Azer Özad; Akar, Zeynep; Kardil, Ugur

  This study was to investigate the biological properties (antioxidant, enzyme inhibitory and antimicrobial activity) of water extract (WE), 50:50% water:ethanol extract (WEE) and ethanol extract (EE) of aerial parts of Alchemilla vulgaris L. which was traditionally used to alleviate and treat many diseases. The WEE extract exhibited the highest total phenolic content (TPC), with a value of 612 µg/mL GAE, while the EE extract demonstrated the highest total flavonoid content (TFC), with a value of 0.086 µg/mL GAE. Also, the data demonstrated that the WEE extract exhibited the highest radical scavenging capacities and antioxidant activities, exhibiting 0.0056, 0.0028 mg/mL SC50 and 267, 0.081 μM TEAC, as determined by the DPPH, ABTS, FRAP and CUPRAC assays, respectively. The WEE extract was found to be an effective bovine carbonic anhydrase (BCA) and α-glucosidase inhibitor with an IC50 values of 0.0628 and 0.0535 mg/mL, respectively. The EE extract showed activity against both Gram-negative and Gram-positive bacteria used in the study. EE extract has the highest activity against Yersinia pseudotuberculosis and the lowest activity against Streptococcus pyogenes. Furthermore, the extracts significantly reduced the biofilm ability of Acinetobacter baumannii isolate, which has strong biofilm ability. EE and WE reduced the biofilm formation capacity of the strain to a weak level, while WEE extract reduced it to a moderate level. The results suggest that EE has a significant effect in combating antibiotic resistance, while WEE has high antioxidant activity and good inhibitory effect against BCA and α-glycosidase enzymes. In addition, the results revealed that solvent extracts with different solvent composition and polarity may have different effects on diverse bioactivity tests.

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• MakaleAçık Erişim2025/r/gumushane/14055
  Investigation of virulence factor genes and biofilm formation of antibiotic resistant clinical E.coli isolates

  Mumin, Yahye Mohamud; Yüksel, Gamze; Özad Düzgün, Azer

  Purpose: The aim of this study is to investigate the antibiotic sensitivity, presence of virulence genes and biofilm formation capacity of 90 clinical E. coli isolates. Methods: The presence of virulence genes in E. coli isolates were investigated by PCR. Ninety clinical isolates of E. coli were subjected to biofilm quantitative analysis using the semi-quantitative crystal violet staining method. Results: it was observed that the isolates were resistant to quinolone, cephalosporin, aminoglycoside, carbapenem and penicillin group antibiotics. The presence of virulence factor genes were observed in a total of 86/90 E. coli. The highest rate of fim (92.2 %) virulence factor gene was detected in the strains. Afa, pap, cnf, sfa, hly were detected in 30 %, 13 %, 13 %, 3.3 %, 2.2 % respectively. Also, 13 different virulence factor gene patterns were determined in 90 E. coli isolates. Of the 90 E. coli isolates whose biofilm-forming capacities were evaluated, 42 were found to have biofilm-forming capacity. Of these 26 (28.8 %) the weak, 12 (13.3 %) moderate and 4 (4.4 %) strong biofilm-forming. Also, statistical analysis was performed to investigate the relationship between virulence factor genes and biofilm formation, and none of the 7 genes analyzed showed a significant relationship with biofilm formation. Conclusion: since pathogenic E. coli is an important public health problem, investigating antibiotic resistance, virulence factor genes and biofilm formation in bacterial pathogens is important for better treatment options.

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• MakaleAçık Erişim2025/r/gumushane/12487
  DYE REMOVAL PERFORMANCE AND BIOLOGICAL ACTIVITIES OF IRON OXIDE NANOPARTICLES SYNTHESIZED FROM Cotoneaster sp. FRUIT EXTRACT

  Akar, Bülent; Baltacı, Cemalettin; Düzgün, Azer Özad; Karpuz, Omer; Karakullukçu, Volkan; Erdoğdu, Esma Gülbahar

  This work aimed to study the antioxidant, antibacterial, and dye adsorption capabilities of the aqueous extract of Cotoneaster sp. fruits (CFE) and iron oxide nanoparticles (CF-FeONP) green-synthesized from the CFE. CF-FeONPs were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses. The antioxidant activity of CFE and CF-FeONPs was assessed through various tests, including ABTS radical scavenging activity, DPPH radical scavenging activity, iron-reducing antioxidant power (FRAP), total phenolic content (TPC), total flavonoid content (TFC), and total antioxidant content (TAC). The CF-FeONPs had superior antibacterial and antioxidant activity compared to the CFEs. Furthermore, CF-FeONPs suppressed the growth of Gram-negative bacteria such as Yersinia pseudotuberculosis ATCC 911, Escherichia coli ATCC 25922, Proteus vulgaris ATCC 13315, and Pseudomonas aeruginosa ATCC 43288, as well as by Gram-positive bacteria like Streptococcus pyogenes ATCC 19615, Staphylococcus aureus ATCC 25923. and Bacillus subtilis ATCC 6633. The microdilution medium technique was used to determine the minimum inhibitory concentration (MIC) of CFE and CF-FeONPs against these bacteria strains. The adsorption rates of CF-FeONPs exhibited variability based on the quantity of adsorbent used and the specific dye type, whereas the lowest adsorption rate was 250 mg/L. CF-FeONPs demonstrated higher adsorption capacities for malachite green (MG) dye compared to methylene blue (MB) and phenol red (PR).

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• MakaleAçık Erişim2024/r/gumushane/19896
  Investigation of antibiofilm and biological activities of Vaccinium arctostaphylos L.

  Düzgün, Azer Özad; Akar, Zeynep; Kardil, Ugur

  This study investigated the total phenolic and flavonoid contents and the antioxidant, antimicrobial, antibiofilm and α-glucosidase inhibitory activities of methanol extract from Vaccinium arctostaphylos L. leaf and fruit parts. The highest antioxidant activity with 53 µM TEAC and 0.0084 mg/mL SC50 using the ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays, respectively determined in leaf part. The data indicated that the leaf of the plant had the higher total phenolic content (49 µg/mL GAE) and total flavonoid content (0.071 µg/mL QAE) compared to fruit. The α-glucosidase enzyme activity of the leaves (0.179 mg/mL IC₅₀) was observed to be higher than that of the fruits (0.386 mg/mL IC₅₀). The MIC values of the leaf and fruit parts of blueberry were 6.25 mg/ml and 3.125 mg/ml, respectively. The results of this study indicate that the leaf extract was found to significantly reduce the biofilm-forming capacity of the Acinetobacter baumannii isolate by approximately 3-fold, whereas the fruit extract was observed to have only a marginal effect, reducing the biofilm-forming capacity by approximately 1.4-fold. The effects of plant extracts on microbial biofilms may be examined with a view to combating antibiotic resistance. Also results suggesting that it might be an effective and safety medical plant to prevent or treat diseases associated with oxidative damage and bacterial infections. Consequently, further research on natural substances may lead to the development of treatment options.

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• MakaleAçık Erişim2024/r/gumushane/19845
  Vitis Labrusca L. Kabuk Ekstraktlarının Antibiyofilm, Antidiyabetik ve Antioksidan Potansiyelleri

  Düzgün, Azer Özad; Akar, Zeynep; Kardil, Ugur

  Bu çalışmada, Vitis labrusca L. bitkisinin kabuk kısımlarından elde edilen metanol, 50:50% metanol:su ve su ekstraktlarının antioksidan, antimikrobiyal, antibiyofilm ve α-glukozidaz inhibitör aktiviteleri ile toplam fenolik ve flavonoid içerikleri incelenmiştir. 50:50% metanol:su özütü, sırasıyla FRAP ve DPPH• radikal süpürücü analizleriyle belirlendiği üzere, 153 μM TEAC ve 0,0947 mg/mL SC50 ile en yüksek antioksidan aktiviteyi sergilemiştir. 50:50% metanol:su ekstraktı, sırasıyla 141 μg/mL GAE ve 0,103 mg/mL IC₅₀ değeri ile diğer çözücü ekstraktları arasında en yüksek toplam fenolik içeriği ve α-glukozidaz enzim inhibisyonunu sergilemiştir. Metanol, su ve 50:50% metanol:su ekstraktlarının MİK değerleri, klinik antibiyotik direnci olan Acinetobacter baumanii' ye karşı sırasıyla 6.25, 25 ve 12.5 mg/mL olarak belirlenmiştir. Metanol, su ve %50:50 metanol:su ekstraktlarının Acinetobacter baumannii izolatının biyofilm oluşturma kapasitesini sırasıyla yaklaşık 1.7, 1.6 ve 1.3 kat azalttığı bulunmuştur. Bulgular, 50:50% metanol:su ekstraktının en yüksek fenolik içerik, antioksidan aktivite ve α-glukozidaz inhibisyonu sergilediğini, metanol ekstraktının ise en belirgin antimikrobiyal ve antibiyofilm aktivitelerini gösterdiğini ortaya koymuştur. Araştırmamızın sonuçları, çeşitli çözücülerin ve bunların ilgili bileşimlerinin kullanımının biyolojik aktivitede önemli farklılıklar yaratma kapasitesine sahip olduğunu göstermektedir. Bu durum, V. labrusca kabuk bileşenlerinin oksidatif stres ve bakteriyel enfeksiyonlarla ilgili rahatsızlıkların ele alınmasında değerli bir yol olarak hizmet etme potansiyeline işaret etmektedir.

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• MakaleAçık Erişim2024/r/gumushane/19843
  Effect of Different Storage Conditions and Infusion Times on Antioxidant and Antimicrobial Activites and Total Phenolic Content of Rosehip Fruits

  Düzgün, Azer Özad; Acet, Tuba; Baltaci, Cemalettin; Akmeşe, Osman; Ural, Mustafa Nuri; Akar, Zeynep; Darak, Münevver; Kılınç, Kagan

  Rosa canina L. (Rosehip) is a medicinal plant with strong antioxidant properties.The content of rosehip and accordingly its antioxidant capability may vary according to the way the fruits are used, storage, infusion, freezing and drying methods. In study, it was aimed to determine the antioxidant, antimicrobial activities in rosehip infusion products and extracts under these conditions. Fresh, frozen, dried and +40C stored fruits were infused at 90 degrees and infusion groups were formed. During infusion, samples were taken at 30, 60, 90, 120, 300 and 360th minutes and antioxidant activity (DPPH, FRAP and ABTS methods), total phenolic and total flavonoid contents (TPC and TFC), and antimicrobial activity were analyzed. In addition, phenolic compound content was investigated in 3 different extracts by HPLC method. Dried rosehip (DR) infusing samples were found to have the highest antioxidant activity, TPC and TFC compared to all groups (p-value ranged between 0.000 and 0.05).). Significant decreases were detected in the parameters according to storage and freezing times. A total of 8 phenolic compounds, the highest concentration of which was epicatechin, were detected in aqueous and ethanolic extracts of dried and stored at 40C rosehip (DR+40C) and dried rosehip (DR) fruits. For antimicrobial analysis, Total 7 different Gram (+) and (Gram (-) bacterial strains, were used. While antimicrobial activity was observed in the extracts, no activity was observed in the infusion products. It was determined that antioxidant activity increased during 360 minute infusion time, although it varied according to storage conditions.

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• MakaleAçık Erişim2024/r/gumushane/12720
  Investigation of Antibiofilm and Antibacterial Properties of Green Synthesized Silver Nanoparticles from Aqueous Extract of Rumex sp.

  Akay, Seref; Yüksel, Gamze; Özad Düzgün, Azer

  The decrease in the effectiveness of conventional drugs as a result of the growth of resistance to antibiotics has increased the need for innovative tools to control the infections. At this point, metallic nanoparticles, in particular silver nanoparticles, have appeared as a promising method. In the current study, the extract of Rumex sp. (Labada, dock) leaves was used as a reducing agent for the formation of silver nanoparticles. Unlike similar studies, in this study the synthesis conditions were optimized by changing the extract ratio and silver nitrate concentration. Morphological investigations of synthesized silver nanoparticles showed that spherical homogeneous particles at size under 100 nm had been produced. SEM/EDS and FTIR analyses showed that plant components are involved in the synthesis of nanoparticles. It was also determined that higher extract ratio reduced nanoparticle size. The antimicrobial effects of the synthesized nanoparticles against Gram-positive and Gram-negative bacteria were tested, and it was determined that all nanoparticles exhibited activity against both groups. Rumex sp. silver nanoparticles (NPs) were revealed to exhibit antibiofilm activity against three different isolates with moderate and strong biofilm-forming ability. The NPs reduced the biofilm-forming capacity of Acinetobacter baumannii and Klebsiella pneumonaie by 2.66-fold and 3.25-fold, whereas they decreased the Escherichia coli biofilm-forming capacity by 1.25-fold. The investigation of microbial biofilm could play an important role in developing new strategies for treatment options. Our results suggest that Rumex sp. silver NPs may have a high potential for use in the treatment of pathogenic strains.

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• MakaleAçık Erişim2024/r/gumushane/12580
  Determination of the Cytotoxicity and Antibiofilm Potential Effect of Equisetum arvense Silver Nanoparticles

  Akar, Zeynep; Akay, Seref; Ejder, Nebahat; Özad Düzgün, Azer

  This study aimed to synthesize and characterize silver nanoparticles (AgNPs) by green synthesis from Equisetum arvense (Ea) extracts and to investigate their cytotoxicity, antibiofilm activity, and α-glucosidase enzyme inhibition. Diverse characterization techniques were applied to verify the production of nanoparticles. SEM examination confirmed that the size of nanoparticles is in the range of 40–60 nm. Also, interactions between silver and natural compounds of plant extract were confirmed through FT-IR and EDX analyses. It was determined that Equisetum arvense silver nanoparticles had antibiofilm activity against three different clinical strains with high biofilm-forming ability. AgNPs reduced the biofilm-forming capacity of clinical A. baumannii isolate with strong biofilm-forming capacity by approximately twofold, while the capacity of clinical K.pneumonaie and E.coli isolates decreased by 1.5 and 1.2 fold, respectively. The α-glucosidase enzyme inhibition potential of the AgNPs, which is determined as 93.50%, was higher than the plant extract with, and the α- 30.37%. MTT was performed to assess whether incubation of nanoparticles with A549 and ARPE-19 cell lines affected their viability, and a dramatic reduction in cell growth inhibition of both A549 and ARPE-19 cells was observed. It has been shown that A549 cells treated with 200 and 150 µg/mL nanoparticles had less cell proliferation compared to control cells at 24-h and 48-h incubation time. According to these results, Ea-derived AgNPs appear to have potential anticancer activity against A549 cancer cells. Investigating the effects of green synthesis nanoparticles on microbial biofilm and various tumors may be important for developing new therapies. The outcomes of this study have showed that Ea-AgNPsmay have a high potential both in the treatment of pathogenic strains that form biofilms, as well as in anticancer therapy use.

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