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Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2026/r/gumushane/12273
  Antibacterial Efficiency and Osteoblast Viability of Ag/AgO/Ag2O Nanoparticles on Microarc-Oxidized TiO2

  Aktas, Sitki; Durdu, Salih; Bird, Toby W.; Ozcan, Kadriye; Yigitturk, Gurkan; Aktug, Salim Levent; Usta, Metin; Acet, Tuba; Pratt, Andrew

  Infections associated with titanium-based medical and dental implants present a major clinical challenge, as they can compromise osseointegration and long-term implant stability. Silver-based nanoparticles (NPs) are widely recognized for their strong antimicrobial properties, and when combined with titanium, they hold significant promise for developing infection-resistant and biocompatible implant surfaces. In this study, Ag/AgO/Ag2O NPs were deposited onto highly porous TiO2 layers formed on the Ti6Al4V alloy by microarc oxidation (MAO), with the aim of simultaneously enhancing antibacterial performance and supporting osteoblast activity. The NPs exhibited a predominant size of 8.7 ± 0.1 nm, with smaller particles oxidized to AgO and Ag2O, and larger particles (∼10 nm) composed of metallic Ag. SEM evaluation revealed that the NPs were homogeneously dispersed across the oxide surfaces without altering the rough and porous morphology of TiO2. The MAO-treated surfaces initially showed hydrophobic behavior (contact angle of 94.1 ± 0.3°), which shifted to hydrophilic after Ag/AgO/Ag2O NP deposition due to increased hydroxyl group formation. Antibacterial assays against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) revealed a significant enhancement in antibacterial activity, particularly for surfaces with the highest Ag/AgO/Ag2O NP density. Meanwhile, osteoblast cell viability assays demonstrated no reduction in metabolic activity after 72 h, and SEM images confirmed cell adhesion and proliferation. Overall, these findings highlight the potential of Ag/AgO/Ag2O NP-modified TiO2 surfaces as multifunctional coatings that combine infection resistance with osteoblast compatibility, offering promising applications in dental and orthopedic implants.

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• MakaleAçık Erişim2025/r/gumushane/14025
  Biological activities and phenolic content of endemic Helichrysum artvinense P.H. Davis et Kupicha (Asteraceae)

  Acet, Tuba; Özcan, Kadriye; Kalmuk, Nursen Aksu

  Species from the Asteraceae family have been extensively utilized in traditional medicine and as food sources for centuries. They also exhibit important biological activities attributed to their diverse array of phytochemical compounds. This research aimed to determine total phenolic and flavonoid contents of ethanol (EtOH) and methanol (MeOH) extracts of endemic Helichrysum artvinense and to reveal its antioxidant, antimicrobial enzyme inhibitory (α-glucosidase, α-amylase, and tyrosinase) and DNA protective activities. In addition, phenolic compound analyses were conducted using high-performance liquid chromatography (HPLC), establishing a correlation with the aforementioned biological activities. Based on the obtained data, the ethanol (EtOH) extract of the plant demonstrated greater prominence in terms of the screened biological activities. This extract was found to contain significant phenolic components, including epicatechin, chlorogenic acid, and luteolin. Consequently, it appears that the plant has the potential to serve as a natural alternative in both food and pharmacological applications. However, further studies to elucidate the mechanisms underlying the observed biological activities would be beneficial for the product development phase.

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• MakaleAçık Erişim2025/r/gumushane/12459
  The biological activity and phenolic content of endemic Astragalus baibutensis

  Ozcan, Kadriye; Acet, Tuba; Yiğittürk, Gürkan

  Astragalus baibutensis, is a plant endemic to Turkey, belonging to Fabaceae family, that is used as a folk medicine and food in this country. The purpose of this study is to find out the biological activities such as antioxidant, antimicrobial, enzyme inhibitory and DNA protective activity and also analyse the phenolic contents of the plant. To determine of antioxidant activity ABTS and DPPH assays were performed. Disc diffusion and microdilution methods were used to evaluate the antimicrobial activity. Additionally, enzyme inhibitory activities such as α-amylase, α-glucosidase, and tyrosinase were determined by using spectrophotometric methods. DNA protective activity was detected using pUC19 Plazmid DNA. The antiproliferative effect on SKOV-3 human ovarian cancer cells was examined by WST-8 assay. In addition, the phenolic contents were analysed by using HPLC. The biological activity of ethyl acetate extract of the root was found to be higher than those of other extracts. This extract had the highest amount of apigenin as phenolic compound. On the other hand, extracts showed moderate inhibition against the tested microorganism and antiproliferative properties in a concentration-dependent manner toward ovarian cancer cells. According to the results, Astragalus baibutensis has the potential for pharmaceutical and food additive usage.

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• MakaleAçık Erişim2024/r/gumushane/10547
  Growth regulation in bread wheat via novel bioinoculant formulation

  Jabran, Muhammad; Ali, Muhammad Amjad; Acet, Tuba; Zahoor, Adil; Abbas, Amjad; Arshad, Usman; Mubashar, Muhammad; Naveed, Muhammad; Ghafoor, Abdul; Gao, Li

  Wheat (Triticum aestivum L.) is one of the most significant crops and the backbone of food security worldwide. However, low wheat production remains a substantial concern in global agricultural systems. It can be attributed to several factors, including adverse climatic conditions, plant disease and poor soil quality. Recent efforts have explored bioinoculant applications as a promising approach to enhance wheat yield, trying to mitigate constraints essential for future wheat production and global food security. This study tested talc powder, wheat biochar, sugarcane bagasse biochar, and farmyard manure as carriers with two endophytic bacterial strains, Burkholderia phytofirmans PsJN and Bacillus spp. MN54 was applied to three wheat varieties (Ujala-16, Zincol-16, and Fathejang-16). The data was recorded at the seedling and maturity growth stages of plants. A pot experiment revealed significant improvements in plant growth following bioinoculant application compared to controls. Notably, the combination of sugarcane bagasse biochar with Bacillus sp. MN54 exhibited the most pronounced effects, promoting internodal length, spike length, tiller number per plant, grain yield per plant, and spikelets per spike. Additionally, talc powder with Bacillus sp. MN54 increased peduncle length, tiller number per plant, and spike length in Fathejang-16. These findings offer valuable insights into optimizing bioinoculant formulations for improved agricultural practices, adapting to climate change, and contributing to ensuring global food security.

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• MakaleAçık Erişim2024/r/gumushane/20072
  Endemik Onosma nana DC.’nin Kimyasal Bileşimi, Antimikrobiyal, Antioksidan ve Enzim İnhibisyon Aktivitesinin Araştırılması

  Ozcan, Kadriye; Acet, Tuba

  Türkçe adı “Emzik otu” olarak bilinen Onosma türleri, etnobotanik açıdan oldukça değerlidir. Bu çalışmada, Onosma nana’nın toprak üstü ve kök kısımlarının farklı çözücülerle (etanol, metanol ve etil asetat) elde edilen ekstrelerinin antioksidan, antimikrobiyal, enzim inhibisyon (α-amilaz, α-glukozidaz ve tirozidaz) ve DNA koruyucu aktivitesi ile fenolik bileşen analizinin (HPLC) yapılması amaçlanmıştır. Elde edilen sonuçlara göre, etanol ekstrelerinin diğer ekstrelere nazaran araştırılan özellikler bakımından daha etkin olduğu bulunmuştur. Etanol ekstrelerinin major fenolik bileşeni rosmarinik asit (kök: 2883.3 μg/g ekstre, toprak üstü: 11187.5 μg/g ekstre) olarak tespit edilmiştir. Sonuç olarak, bitkinin oldukça etkili antimikrobiyal aktiviteye sahip olduğu bulunmuştur (S. epidermidis ve P. vulgaris: MİK 32µg/mL). Bitkinin DNA koruyucu etkisi ve antimikrobiyal özellikleri ilk defa araştırılmıştır. Bitkinin doğal bir ajan olarak kullanılma potansiyeli olduğu söylenebilir. Bunun yanısıra, tespit edilen aktivitelerin detaylı çalışmalarla desteklenerek etki mekanizmalarının aydınlatılması ticari öneminin anlaşılması bakımından gereklidir.

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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 Erişim2023/r/gumushane/20418
  Helichrysum chionophilum’un uçucu yağının antioksidan ve antimikrobiyal aktiviteleri: Türkiye'nin endemik bir bitkisi

  Ozcan, Kadriye; Acet, Tuba

  Mikroorganizmalara bağlı olarak gelişen rahatsızlıklar günümüzde giderek tehlikeli bir hal almıştır. Özellikle, dirençli organizmalar ile mücadele noktasında, daha ucuz, doğal ve etkili yöntemlere ihtiyaç duyulmaktadır. Biyolojik olarak aktif bileşikleri barındıran bitki materyalleri bu manada ön plana çıkmaktadır. Bu nedenle, mevcut çalışmada, Gümüşhane'den toplanan Helichrysum chionophilum'dan elde edilen uçucu yağın antioksidan ve antimikrobiyal aktiviteleri araştırılmıştır. Uçucu yağ, Clevenger tipi bir aparat kullanılarak hidro-damıtma yönteminden elde edildi. Serbest radikal yakalama aktivitesi, DPPH (2,2-difenil-1-pikrilhidrazil) yöntemi kullanılarak belirlendi. Antimikrobiyal aktivite mikro dilüsyon yöntemi kullanılarak 17 bakteri ve 2 maya kullanılarak incelendi. Elde edilen bulgulara göre, H. chionophilum bitkisi radikal süpürme aktivitesinin IC50 değeri 260.0±0.2 µg/mL olarak bulunmuştur. Ayrıca, bitkinin uçucu yağı, Y. pseudotuberculosis (MIC: 16 µg/mL), S. epidermidis (MIC: 16 µg/mL) ve C. albicans (MIC: 16 µg/mL) ve C. tropicalis'e (MIC: 32 µg/mL) karşı olağanüstü antimikrobiyal aktivite göstermiştir. Elde edilen sonuçlar, endemik bir tür olan H. chionophilum ve uçucu yağlarının antioksidan ve antimikrobiyal özellikleri sayesinde yeni ve alternatif doğal bir ajan olarak kullanılabileceğini işaret etmektedir.

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• MakaleYalnız künye2023/r/gumushane/11623
  Investigation of the effect of liquid phase of digested biomass on Phaseolus vulgaris L. var. ellipticus Mart under NaCl stress

  Çiftçi, Fida; Acet, Tuba; Saribiyik, Oǧuz Yunus

  The factors such as global warming, wild irrigation, and synthetic fertilisers pollute the soil and increase salinity. The salinity is defined as salt stress for plants, and plants have developed various tolerance mechanisms to survive under salt stress conditions. Therefore, efforts to increase the tolerance of salt sensitive plants such as beans (Phaseolus vulgaris) are considered important. Additionally, considering problems that appear depending on global warming, understanding the tolerance mechanisms, and activating them by using natural and sustainable solutions are important for plant growth and preventing lower agricultural productivity. In this study, the effect of biofertiliser obtained from a small-scale bioreactor on a plant exposed to salt stress on the development of morphological, physiological, and biochemical properties of the model plant, Phaseolus vulgaris L. var. ellipticus Mart (Pve) were investigated. The biofertiliser application increased the amount of chlorophyll, flavonoids, anthocyanin, and proline while the amount of hydrogen peroxide and lipid peroxidation decreased in the plant. This change enhanced the enzyme activities of catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX) and the plant formed tolerance to the salt stress. As a result, the biofertiliser application to the plant may activate the tolerance mechanism against salt stress.

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• MakaleAçık Erişim2022/r/gumushane/17037
  Stachys macrantha (K.Koch) Stearn’ın Biyolojik Aktivitesinin Belirlenmesi

  Ozcan, Kadriye; Acet, Tuba

  Stachys, Lamiaceae familyasının en geniş yayılış gösteren cinslerinden birisidir. Bu cinse ait türler biyolojik aktiviteleri ve etnomedikal kullanımları ile bilinmektedir. Bu çalışmada, Stachys macrantha’nın toprak üstü kısımlarının farklı çözücülerle (etanol, metanol ve etil asetat) elde edilen ekstraktlarının toplam fenolik ve flavonoid içeriği ile antioksidan (ABTS, DPPH) ve enzim inhibisyon (α-amilaz, α-glukozidaz, bütirilkolinesteraz ve asetilkolinesteraz) aktiviteleri spektrofotometrik yöntemlerle araştırılmıştır. Ayrıca, fenolik bileşen analizi HPLC ile analiz edilmiştir. Bulgulara göre, metanol ekstraktının diğer ekstraktlara kıyasla biyolojik aktivitelerinin dikkat çekici olduğu bulunmuştur. Ekstraktın, toplam fenolik (45.57 mg GAE/g ekstrakt) ve flavonoid (54.48 mg QE/g ekstrakt) içeriği, antioksidan özellikleri [ABTS (49.99 mg TE/g ekstrakt), DPPH (23.62 mg TE/g ekstrakt)] ile enzim inhibisyon aktiviteleri [α-amilaz (159.35 mmol ACE/g ekstrakt), α-glukozidaz (8.78 mmol ACE/g ekstrakt), bütirilkolinesteraz (5.85 mmol ACE/g ekstrakt) ve asetilkolinesteraz (1.25mmol ACE/g ekstrakt)] belirlenmiştir. Metanol ekstraktının majör fenolik bileşenlerinin kaemferol (539.65 µg/g ekstrakt) ve kuersetin (271.65 µg/g ekstrakt) olduğu tespit edilmiştir. Elde edilen sonuçlara göre, bitkinin tespit edilen aktiviteleri sayesinde ilaç, gıda ve kozmetik endüstrilerinde kullanılma potansiyeli olduğu söylenebilir. Bununla birlikte, söz konusu verilerin daha ileri çalışmalarla desteklenmesi ve aktif bileşenlerin saflaştırılarak etkilerinin in vivo ortamlarda belirlenmesi gerekmektedir.

  İncele
• MakaleAçık Erişim2022/r/gumushane/16958
  Heracleum pastinacifolium’nın Antioksidan ve Antimikrobiyal Özellikleri İle Fenolik İçeriğinin Aydınlatılması

  Ozcan, Kadriye; Acet, Tuba

  Yaban otu olarak bilinen Heracleum türleri, geleneksel olarak gıda katkı maddesi, baharat ve tatlandırıcı olarak kullanılmaktadır. Bunun yanı sıra, etnobotanik özellikleri olduğu da bilinmektedir. Bu çalışmada, endemik Heracleum pastinacifolium’un farklı çözücülerle (etanol, metanol ve etil asetat) elde edilen özütlerinin toplam fenolik ve flavonoid içeriği ile antioksidan ve antimikrobiyal aktiviteleri spektrofotometrik yöntemlerle araştırılmıştır. Ayrıca, fenolik bileşen analizi HPLC ile analiz edilmiştir. Bulgulara göre, metanol özütünün diğer özütlere kıyasla antioksidan ve antimikrobiyal özelliklerinin dikkat çekici olduğu bulunmuştur. Metanol özütünün başlıca fenolik bilşenlerinin kaemferol (726.05 µg/g özüt) ve kuersetin (451.6 µg/g özüt) olduğu tespit edilmiştir. Elde edilen veriler ışığında, bitkinin endüstriyel kullanım potansiyeli olduğu söylenebilir. Bununla birlikte, daha ileri çalışmalarla verilerin desteklenmesi ve aktif bileşenlerin saflaştırılarak canlılar üzerindeki etkilerinin belirlenmesi önem arz etmektedir. 

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