Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2026Antibacterial 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.
- MakaleAçık Erişim2025Biological 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.
- MakaleAçık Erişim2025The 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.
- MakaleAçık Erişim2024Endemik 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.
- MakaleAçık Erişim2024Effect 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.
- MakaleAçık Erişim2024Growth 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.
- MakaleAçık Erişim2023Helichrysum 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.
- MakaleYalnız künye2023Investigation 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.
- MakaleAçık Erişim2022Stachys 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.
- MakaleAçık Erişim2022Heracleum 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.
- MakaleYalnız künye2022Chemical profile, antioxidant, antimicrobial, and enzyme inhibition activities of Pilosella hoppeana subsp. cilicica
Acet, Tuba
Pilosella hoppeana subsp. cilicica has been traditionally used for healing many diseases in folk medicine in Anatolia. However, there are, to date, no studies aimed to verify this local usage with scientific data. In the present study, phenolic content and biological activities such as the antioxidant, antimicrobial and enzyme inhibition activities of different extracts of this plant’s aerial part were investigated for the first time. According to the obtained data, the biological activity of methanol extract was found to be significantly higher than the others. Moreover, the major components detected were chlorogenic acid (61.79 mg g−1 extract), apigenin (2.727 mg g−1 extract), and luteolin (1.110 mg g−1 extract) in this extract. This extract showed a strong enzyme inhibitory activity including α-amylase (96.66 mmol ACAE g−1 extract), α-glucosidase (17.27 mmol ACAE g−1 extract), AChE (10.42 mg GALE g−1 extract), and BChE (102.35 mg GALE g−1 extract). On the other hand, the extract exhibited remarkable antimicrobial effect on Yersinia pseudotuberculosis, and Staphylococcus epidermidis (64 µg/mL MIC value); intermediate (128–256 µg/mL MIC value) antimicrobial activity on Proteus vulgaris, Listeria innocua, and vancomycin-resistant Enterococcus faecium. To sum up, it is clearly seen that Pilosella hoppeana subsp. cilicica has significant potential as a source of bioactive compounds in pharmaceutical industries.
- MakaleAçık Erişim2022Investigation of the effects of different extraction methods on some biological activities of Dactylorhiza romana subsp. georgica (Klinge) Soó ex Renz & Taubenheim
Bozkir, Buğra; Acet, Tuba; Özcan, Kadriye
Dactylorhiza romana subsp. georgica is found in Anatolia and is traditionally used by local people both as food and to alleviate various ailments. Although various biological activities of the plant have been partially investigated, these properties have not been comprehensively revealed in the light of scientific data. In this study, it was aimed to elucidate the antioxidant, antimicrobial, enzyme inhibition (alpha amylase, alpha glucosidase, and tyrosinase) and DNA protective activity and phenolic content of the extracts obtained from orchid tubers using different extraction methods. For this, the fresh and dry tubers of the plant were extracted with ethanol at different times in an ultrasonic water bath, shaker and their combinations with each other. ABTS, DPPH, and FRAP methods were used to determine the antioxidant properties of plant tubers. In addition, the phosphomolybdate method was used to determine the total antioxidant capacity. The spectrophotometric method was preferred to reveal the enzyme inhibition activity. The antimicrobial activity of the extracts was investigated by microdilution method. In addition, the phenolic content of the plant was analysed by HPLC. The DNA protective activity of the extracts was determined by using the pUC 19 plasmid. According to the results obtained, it was revealed that each extract exhibited various biological activities. According to the HPLC results, the highest phenolic component in the extracts was determined as p-hydroxybenzoic acid. As a result, it was observed that the biological activities of orchid tubers changed according to different extraction methods. Accordingly, due to the high biological activities of orchid tubers, they have a high potential for use in the food and pharmaceutical industries.
- MakaleYalnız künye2021Determining the phenolic components by using HPLC and biological activity of Centaurea triumfetti
Acet, Tuba
Centaurea species belonging to Asteraceae family are traditionally used herbs in treating many diseases in Anatolia. In the present study, I aimed to determine the biological activities and phenolic contents of the extracts of the aerial parts of Centaurea triumfetti collected from areas with extreme climatic conditions. The determination of antioxidant activity was performed using in vitro assays such as ABTS (2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) and DPPH (1,1-diphenyl-2-picrylhydrazyl). Disc diffusion and microdilution methods were used for determine of antimicrobial activity. Besides that, the diabetes-related inhibition activities of enzymes such as alpha-glucosidase and alpha-amylase were determined using colorimetric methods. The phenolic components of the extracts were analysed by using HPLC. The biological activity of ethyl acetate extracts of the stem was found to be higher those than that of other extracts. This extract was also found to have high antimicrobial and enzyme inhibition activity. Moreover, the major component of the extract was found to be chlorogenic acid. In conclusion, these results suggest that C. triumfetti has the potential for pharmaceutical usage.
- MakaleYalnız künye2021Biological activity of Psephellus appendicigerus as a natural agent
Acet, Tuba; Özcan, Kadriye; Sefalı, Abdurrahman
Psephellus appendicigerus, is a plant endemic to Turkey, belonging to the Asteraceae family, which is traditionally used in folk medicine in Turkey. The aim of this study is to reveal for the first time the biological activities of this plant and evaluate its potential use as a natural product. For this reason, different extracts (ethanol, methanol, ethyl acetate, and hexane) of the plant’s aerial parts were used in determining the antioxidant (2,20-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid and 1,1-diphenyl-2-picrylhydrazyl assays), antimicrobial (disc diffusion and microdilution methods), and enzyme inhibition activity (calorimetric methods) related to diabetes (α-amylase and α-glucosidase). Moreover, the phenolic constituents were analysed by high performance liquid chromatography. Methanol extract of the plant exhibited significant biological activity compared to other extracts. This extract had the highest amount of chlorogenic acid as phenolic compound. In addition, all extracts showed inhibition against at least one test microorganism. According to the results, P. appendicigerus has the potential to be used as a natural antioxidant, antimicrobial and enzyme inhibitor.
- MakaleAçık Erişim2021Phenolic contents and biological activities of two endemic plants in Turkey
Acet, Tuba; Çorbacı, Cengiz; Özcan, Kadriye
In the paper, the phenolic compounds and biological activity of Corydalis oppositifolia DC. and Senecio cilicius Boiss., the endemic plants growing in Turkey, were investigated for the first time. The ethanol extract of C. oppositifolia exhibited more potent antimicrobial activity while the ethanol extract of S. cilicius exhibited the highest radical scavenging activity on ABTS (81.4±1.1a mg TE g−1 extract) and DPPH (23.4±0.2a mg TE g−1 extract). In C. oppositifolia, the highest total flavonoid and phenolic acid contents were found to be in the ethanol (94.2±3.5a mg QE g−1 extract) and methanol (320.5±3.3c mg GAE g−1 extract) extracts, respectively. In S. cilicius, the highest total flavonoid and phenolic acid contents were found to be in the methanol (56.9±0.9c mg QE g−1 extract) and ethanol (568.0±3.3a mg GAE g−1 extract) extracts, respectively. The ethanol extract of C. oppositifolia has the most prominent activity against α-amylase, AChE and BChE whereas the methanol extract of this plant displayed the highest inhibitory activity against α-glucosidase. HPLC analysis of the ethanol extracts revealed that the major flavonoids were kaempferol and quercetin whereas the major phenolic acids were protocatechuic acid, gallic acid, gentistic acid and 2,4-dihydroxybenzoic acid. The findings suggested that the plants and their extracts have the potential to be used in the treatment of diseases such as diabetes and Alzheimer's diseases.
- MakaleAçık Erişim2020Determination of Antioxidant and Antimicrobial Activities and Synergistic effect with Antibiotics of Morus nigra L. Extracts Grown in Elazig Province
Ozcan, Kadriye; Acet, Tuba; Akmeşe, Osman
Possible side effects of drugs used as antimicrobial agents and microorganisms' resistance to these drugs pose a great danger to human health. This situation led to the scientific community to new searches. It is known that many herbal products consumed as food are also used by the public for the protection of diseases. However, many of these are still not confirmed by scientific data. In this regard, in the current study, Morus nigra L. (black mulberry) fresh fruit extracts (ethanol, methanol and ethyl acetate) collected from Elazığ province and used by local people to alleviate many diseases, total antioxidant content of total phenolic and total flavonoids capacities were determined. However, the phytochemical content of the ethanol extract was evaluated by RP-HPLC. In addition, their antimicrobial properties and synergies with antibiotics (chloramphenicol, novobiosin and nalidixic acid) were tested. The total phenolic content value and antioxidant properties of ethanol extract were significantly higher than the others. The major component of this extract was determined as chlorogenic acid. It was determined that the extracts showed low efficacy against the test microorganisms, however, all extract antibiotic mixtures exhibited a full synergistic effect on P. aeroginosa, a serious pathogen, except for the methanol extract / chloramphenicol combination. The full synergy is important in terms of ensuring that the antibiotic is more effective at a lower dose. As a result, due to the biological activities of M. nigra fruit extracts, it is thought to have the potential to be used as a natural and alternative source in the food and pharmaceutical industries.
- MakaleAçık Erişim2020SOS5 gene-abscisic acid crosstalk and their interaction with antioxidant system in Arabidopsis thaliana under salt stress
Acet, Tuba; Kadıoğlu, Asım
SOS5 locus, encodes cell wall adhesion protein under salt stress conditions in plants, and it is required for normal cell expansion as well as for sustaining cell wall integrity and structure. However, it is still unknown how this gene locus-ABA cross-talk and interacts with the antioxidant mechanism under salt stress conditions. For this purpose, the study focused on mutant sos5-1 plant treated with ABA under NaCl stress and observed its growth and development as well as stomatal aperture, lipid peroxidation, proline, hydrogen peroxide (H2O2) and ABA contents, and some antioxidant enzyme activities. In addition, the expression levels of ABA related genes have been analysed by RT-PCR after stress application. According to findings, sos5-1 mutant plants treated with ABA under salt stress resulted in eliminated cellular damage compared to those which are solely exposed to salt stress; other observations include closing of stomata, decreased H2O2 content, increased amount of proline, and similarity with the wild type due to induced antioxidant enzyme activities. Besides, both ABA biosynthetic and inducible gene expressions of the mutant plant under salt stress were lower compared to the control, and catabolism gene expression was higher. As a result, SOS5 gene in synergy with ABA, scavenge the ROS by stimulating antioxidant system, leads to an increase in stress related gene expressions and thus contributes to salinity tolerance. This study is significant in the way that it shows how SOS5 gene locus, under salt stress conditions, interacts with antioxidant system in sustaining cell wall integrity.
- MakaleYalnız künye2020Phytochemical profile and biological activity of a therapeutic orchid from Anatolia: Dactylorhiza romana subsp. georgica
Kotiloğlu, Deniz; Acet, Tuba; Özcan, Kadriye
In Anatolia, the tubers of Dactylorhiza romana subsp. georgica orchid are consumed as food and frequently used in folk medicine to alleviate the symptoms of some disorders. However, these properties have not been scientifically studied until the present day. In this research, we aimed to identify phenolic profile of the orchid tubers and determine their several features and functions. Among these, there are the antioxidant and antimicrobial effects and the inhibitory effect against diabetes related enzymes (α-amylase and α-glucosidase). In this sense, total phenolic content (Folin–Cicalteu assay), total antioxidant capacity (Phosphomolybdate method), antioxidant (ABTS and DPPH assays) and enzyme inhibition effects of tuber extracts obtained with different solvents (chloroform, ethyl acetate, methanol, ethanol, or hexane) were determined by using spectrophotometric methods, and the phenolic profile was also analysed by HPLC. In addition, antimicrobial activity of the extracts against 3 g (+) and 3 g (−) bacteria and 2 forms of yeasts was determined by disc diffusion and micro dilution methods. Based on our findings, the total phenolic content and antioxidant properties of ethyl acetate extract were considerably higher than the others. The most abundant among the screened phenolic standards was found to be benzoic acid. The highest α-amylase and α-glucosidase enzyme inhibition was measured in methanol and chloroform extracts, respectively. The highest antibacterial (B. cereus) and anticandidal (C. tropicalis and C. albicans) activities were detected in the chloroform and ethyl acetate extracts, respectively. In short, it was clearly seen that the D. romana subsp. georgica tuber had a great potential for being used in food and drug industries as a source of bioactive compounds.
- MakaleAçık Erişim2020An assessment of phenolic profiles, fatty acid compositions, and biological activities of two Helichrysum species: H. plicatum and H. chionophilum
Acet, Tuba; Ozcan, Kadriye; Zengin, Gokhan
In the present study, we aimed to search and compare the biological activities of the ethanol (EtOH), methanol (MeOH), and ethylacetate (EtOAc) solvent extracts of the flower, stem, and root parts of two Helichrysum plants (H. chionophilum (Hc) and H. plicatum subsp. plicatum (Hp)). The antioxidant properties were determined by using (2,2-diphenyl-1-picrylhydrazyl) (DPPH) and ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The enzyme inhibitory effects of the extracts were investigated on butyrylcholinesterase (BChE), acetylcholinesterase (AChE), α-glucosidase, and α-amylase. Palmitic acid (C 16:0) was also determined as major fatty acids in the tested oils (31.21%–67.68%). In both plants, it was found that the EtOAc extracts of the flowers had a strong antioxidant and enzyme inhibitory effect. In conclusion, the results obtained in the present study showed that H. chionophilum and H. plicatum can be seen as a promising source for the natural bioactive compounds that can be used in therapeutic applications. Practical applications: The members of the genus Helichrysum have been widely taken for therapeutic purposes in traditional medicine as well as food. In this context, we investigated the chemical characterization and biological activities of two Helichrysum species extracts (H. chionophilum and H. plicatum subsp. plicatum). Antioxidant capacity, enzyme inhibition and anti-microbial effects were tested for biological activities. Chemical characterization was identified by high performance liquid chromatography (HPLC) (for phenolic) and gas chromatography-flame ioanization detector (GC-FID) (for fatty acids). Based on our findings, the species may be valuable for designing novel food products.
- MakaleYalnız künye2019A Study on Antioxidant Properties and Antimicrobial Activity of Various Extracts of Carduus adpressus
Acet, Tuba
The genus Carduus is traditionally used to relieve many ailments in Anatolian folk medicine. In this study, potential antioxidant properties and antimicrobial activity of different plant extracts of Carduus adpressus were investigated. Total polyphenols, total phenolic and total flavonoid contents were made with phosphomolybdate, Folin-Chiocalteu reagent and AlCl3, respectively. Antioxidant activity was determined using ABTS (2,2´-azino-bis, 3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrilhydrazil) methods. Antimicrobial activity was determined by disc diffusion and microdilution methods. Ethanol extract had the highest total antioxidant content (377.9 mg GAE g-1 extract), flavonoid (60.06 mg QE g-1 extract) and phenolic (291.03 mg GAE g-1 extract). In addition, the strongest radical scavenging activity was detected in ethanol extract (ABTS: 78.26 mg TE g-1 extract and DPPH: 74.45 mg TE g-1 extract). All extracts exhibited a high antimicrobial activity against at least one microorganism. As a result, C. adpressus plant is thought to have potential to be used as a natural antioxidant and antimicrobial agent.