Sürdürülebilir Kalkınma Amaçları
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- MakaleYalnız künye2026Effects 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.
- MakaleAçık Erişim2026Green Synthesis and Bioactivities of Silver Nanoparticles Derived from Mercurialis annua L. Extract
Salad, Aisha Mohamud; Akar, Zeynep
Biogenic synthesis using plant materials provides a sustainable alternative to classical nanoparticle fabrication, minimizing chemical hazards and decreasing energy input. In this study, silver nanoparticles (AgNPs) were prepared using an aqueous extract of Mercurialis annua and characterized. Physicochemical properties of the AgNPs were confirmed using ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared (FTIR) analysis, X-ray diffraction (XRD), and transmission electron microscopy coupled with energy-dispersive X-ray (TEM–EDX), which collectively indicated crystalline, spherical silver nanoparticles stabilized by extract-derived functional groups. Subsequently, the biological activities of both the nanoparticles and the extract were comparatively evaluated using antioxidant tests, including cupric ion reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), total phenolic content (TPC), and total flavonoid content (TFC), as well as enzyme inhibition tests targeting α-glucosidase and carbonic anhydrase. Liquid chromatography-mass spectrometry profiling identified 31 phenolic constituents in the extract, with ferulic, caffeic, salicylic, and 4-hydroxybenzoic acids detected in high abundance. Overall, the biosynthesized AgNPs demonstrated higher antioxidant performance and stronger inhibitory effects on both enzymes compared with the crude extract. These results indicate that M. annua-based AgNPs hold considerable promise sustainable and effective bioactive agents for future biomedical and biotechnological applications.
- MakaleAçık Erişim2025Assessment 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.
- MakaleAçık Erişim2024Investigation 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.
- MakaleAçık Erişim2024Vitis 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.
- 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 Erişim2024Determination 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.
- MakaleYalnız künye2023Determination of cytotoxic, anti-acetylcholinesterase and antioxidant activity of some medicinal Artemisia spp.
Gıdık, Betül; Kara, Yakup; Akar, Zeynep; Demir, Elif Ayazoglu; Can, Zehra
The study aims to investigate the antioxidant activities, phenolic compounds, acetylcholinesterase enzyme inhibition and cytotoxic effects of two different Artemisia spp. (Artemisia dracunculus L. and Artemisia dracunculoides Pursh) cultivated in Türkiye organically, for the first time. The total phenolic and total flavonoid contents of the plants were determined spectrophotometrically while antioxidant activity DPPH•, CUPRAC, and FRAP was determined using the colorimetric method. And also, acetylcholinesterase in vitro enzyme inhibition activity and anti-cancer activity against human melanoma (VMM917, CRL-3232), lung carcinoma (A549, CCL-185), and normal human fibroblast (hGF, PCS-201-018) cells were studied. Total phenolic (225-324 μg GAE/mL extract) and total flavonoid contents (0.066-0.085 μg QE/mL extract), antioxidant activity Color Scavenging Concentration 50% (DPPH• (CSC50: 1.371-1.655 mg/mL), CUPRAC (0.246-0.344 μM CTEAC) and FRAP (462.133-726.661 μM CTEAC)). A. dracunculus and A. dracunculoides extracts inhibited 40.09 ± 0.65%, and 39.48 ± 3.68% of acetylcholinesterase activity. It was determined that demonstrated the selective effect of A. dracunculus and A. dracunculoides on the cytotoxicity of A549 and hGF cells. According to our results, both tarragon plant species, it may be said that it is not only consumed as food but also used for therapeutic purposes will be beneficial for health.
- MakaleAçık Erişim2023Green biosynthesis, characterization of silver nanoparticles using a green alga Spirogyra sp. and their antioxidant and enzyme activities
Başoğlu, Aysel; Akar, Zeynep
A simple, environmentally friendly, inexpensive, and one-step alternative method was reported for the green biosynthesis of silver nanoparticles (AgNPs) operating the Spirogyra sp. extract as a reducing and stabilizing substance. Concentration of AgNO3 and reaction time were optimized to prepare AgNPs under controlled conditions. The synthesized silver nanoparticles were characterized by UV-Vis absorption spectroscopy, fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), and elemental mapping. The TEM analysis showed that the average particle size of AgNPs was 18.3 nm. Structural details of silver nanoparticles elucidated by Selected Area Electron Diffraction (SAED) based on TEM images. In addition, biological activity tests were applied to nanoparticles and algal extracts to determine antioxidant activity (3 different tests: DPPH (1,1-diphenyl-2-picrylhydrazil) radical scavenging activity, total phenolic content (TPC) and total flavonoid content (TFC)) and α-glucosidase enzyme inhibition. Antioxidant activity and α-glucosidase enzyme inhibition values of silver nanoparticles are higher than the values of Spirogyra sp. extracts.
- MakaleAçık Erişim2023Chemical Composition of Pistacia terebinthus L. and its Phytochemical and Biological Properties
Fidan, Muhammed Said; Baltaci, Cemalettin; Öz, Mehmet; Akar, Zeynep
Vitamin C, enzyme activities, phenolic compounds, antioxidant capacity, antimicrobial activity, and essential oil analyses of ripe and unripe fruits of P. terebinthus were investigated. Vitamin C amounts of ripe and unripe fruits were 63.2 and 15.4 mg/100g, respectively. The main phenolic compounds of unripe and ripe fruits are rutin, syringic acid, and gallic acid. It was determined that the enzyme inhibitor activities in the ripe and unripe fruits were 0.136 mg/mL and 2.14 mg/mL. In all of the free radical scavenging (DPPH and ABTS) activity, ferric (III) ion reducing antioxidant power (FRAP) capacity, total phenolic substance amounts (TPC), total flavonoid substance amounts (TFC), and total antioxidant activity (TAC) antioxidant methods analyzed with plant parts, the methanol extracts obtained from the ripe fruits of the P. terebinthus showed higher antioxidant properties than the methanol extracts obtained from the unripe fruits. Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 showed antimicrobial activity against microorganisms, while methanol extracts obtained from unripe fruit samples did not show antimicrobial activity against the microorganisms used. The chemical grade with the most compounds in the essential oils of P. terebinthus were monoterpenoids, sesquiterpenes, and monoterpenes in unripe and ripe fruits, respectively. The main components were a-pinene with 22.8% and 27.3% ratios in unripe and ripe fruits, respectively.
- MakaleAçık Erişim2022Determination of LC-MS/MS phenolic profile, antioxidant and α-glucosidase enzyme inhibition activities of Linum mucronatum Bertol. subsp. armenum (Bordz.) P.H.Davis
Akar, Zeynep; Kılıç, Fatma
Plants include compounds having high antioxidant activity such as flavonoids, phenolics, and carotenoids. Antioxidant defense mechanisms play an important role in the prevention and treatment of oxidative stress diseases in humans. In the present study, the flower and leaf parts of Linum mucronatum subsp. armenum were extracted in five different solvents. The antioxidant activities of the extracts were determine using six antioxidant activity determination assays (Iron (III) reducing/antioxidant power (FRAP), DPPH radical scavenging activity, copper (II) reducing antioxidant activity (CUPRAC), ABTS radical scavenging capacity, total flavonoid content and total phenolic content). While, the methanol extract showed the highest activity for the flower part, ethanol extracts of leaf part showed the highest antioxidant activity in the DPPH, FRAP and CUPRAC tests. The highest activity values in both flower and leaf parts was measured in acetone extract with SC50=0.287 mg/mL and (SC50=0.163 mg/mL in ABTS test, respectively. Lowest activity values of solvent extracts were measured in hexane extracts in all tests. Phenolic compounds of the plant were identified using LC-MS/MS. These phenolics are kaempferol, vanillin, protecatechuic acid, caffeic acid, p-coumaric acid, p-OH benzoic acid, salicylic acid, quercetin and rutin. The leaf and flower parts have α-glucosidase enzyme inhibitor effect. It was determined that the leaf part of the plant (IC50=4.533 mg/mL) have higher enzyme inhibition than in the flower (IC50=6.096 mg/mL). As a result, it was determined that the plant showed the biological activity. The results will contribute to the studies on the biological activity of the other plant.
- MakaleAçık Erişim2021Arum italicum Miller Bitkisinin Yenilebilir ve Yenmeyen Yumru Parçalarının LC–MS/MS ve RP–HPLC–UV Analizi ve Antioksidan Aktiviteleri
Can, Zehra; Akar, Zeynep; Demir, Çağlar; Alkan, Ozan; Akar, Bülent
Bu çalışmada, Arum italicum bitkisine ait yumrunun yenilebilir ve yenmeyen kısımlarından elde edilen metanolik ve sulu ekstraktların, fenolik içerikleri ve antioksidan aktiviteleri belirlenmiştir. Ek olarak, bitkinin bu kısımlarının antioksidan potansiyeli, fenolik kompoziyonu ile ilişkilendirilmiştir. Bitkinin antioksidan aktivitesini belirlemek için Toplam Fenolik Madde Miktarı, FRAP, CUPRAC ve radikal süpürme aktiviteyi belirleyen DPPH antioksidan aktivite testleri yapılmıştır. Bitki yumrusunun her iki kısmındaki fenolik profiller hazırlanan metanolik ekstraktlarında RP– HPLC–UV ve LC–MS/ MS cihazları kullanılarak belirlenmiştir. En yüksek toplam fenolik içerik, FRAP, CUPRAC ve % DPPH değerleri, yumrunun yenmeyen kısmının metanolik ekstraktında sırasıyla 164 µg GAE/mL, 878 TEAC(µM), 0.064 TEAC(µM) ve 19.41 olarak ölçülmüştür LC/MS-MS ölçümlerinde her iki yumru kısmının metanolik ekstraktlarında ferulik asit, ana fenolik bileşik olarak belirlendi. Bununla birlikte RP–HPLC–UV ölçümlerinde ise, bitki yumrusunun yenilebilir ve yenilmeyen kısımlarında sırasıyla luteolin ve rutin fenolikleri ana bileşikler olarak ölçülmüştür.
- MakaleAçık Erişim2021Effects of Cold and Hot Infusions on Antioxidant Activities of Rosehip Tea Bag
Akar, Zeynep; Orhan, Erza; Durmuş, Seçil
In this study, the antioxidant activity values of infusions at different temperatures of thecommercially sold rosehip tea bag. To determine the effect of different infusion temperatures onantioxidant activity, 7 different temperatures (0, 15, 30, 45, 60, 75, 90°C) also including coldinfusions temperatures were selected. Infusions of the rosehip tea bags were prepared with packageddrinking water for 5 minutes (recommended time in tea bag packaging) at these temperatures.Antioxidant activity values of the infused extracts were determined by antioxidant activitydetermination methods: TPC (Total Phenolic Compound), CUPRAC (Cu (II) Ion ReducingAntioxidant Capacity), FRAP (Iron (III) Ion Reducing Antioxidant Power) and ABTS•+(2.2-azinobis- (3-ethylbenzothiazoline-6-sulphonic acid)) radical scavenging assay. According to theresults obtained by the antioxidant determination methods, the highest and lowest activity valuesfor TPC, FRAP and ABTS were measured at 90°C and 0°C, respectively, and a positive correlationwas found between temperature and antioxidant activity values. Contrary to the activity valuesdetermined in these methods, in the CUPRAC method, the highest and the lowest activity value wasmeasured at 45°C and 90 °C, respectively. As determined in the CUPRAC method, infusions ofrosehip tea at low temperatures may provide an advantage in terms of the solubility of somephenolics that can be denatured at high temperatures. In addition, rosehip tea infusions at lowertemperatures will contribute to lower energy costs.
- MakaleAçık Erişim2021Chemical compositions by using LC-MS/MS and GC-MS and antioxidant activities of methanolic extracts from leaf and flower parts of Scabiosa columbaria subsp. columbaria var. columbaria L.
Akar, Zeynep
The members of the Scabiosa genus are one of the traditional medicinal plants used in the treatment of many diseases, in particular the treatment of scabies. In this study, it was aimed to determine antioxidant activities and chemical composition of methanolic extracts of leaves and flowers of Scabiosa columbaria subsp. columbaria var. columbaria. The phenolic contents of both parts of the plant were analyzed by LC-MS/MS. A total of 6 phenolic compounds were determined and chlorogenic acid was the major compound in both flower and leaf parts of the plants, with 5936.052 mg/g and 8021.666 mg/g, respectively. 6 different methods were used to determine the antioxidant activity of the plant parts. Both leaf and flower parts of the plant showed high antioxidant activity in all tested methods and the antioxidant activity values of the leaf part were measured higher than those of the flower part for four tests. The methanol extracts of the plant parts was analyzed with GC-MS and number of the essential oil compounds in the leaf and flower parts were determined as 17 and 13, respectively. Linalool compound was also found to be common in both parts of the plant. The major compounds of the essential oils were identified as 4Octadecenal (30.01%) in the flower and carvone (35.44%) in the leaf. In addition, terpene derivatives was determined as 90.32% of the highest essential oil group in the leaf, while this value was determined as 1.42% in the flower. For the flower, aromatics were determined as the main component group with 21.31%. (c) 2021 The Author. Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
- MakaleAçık Erişim2021Investigation of class 1 integrons with antibiotic resistance genes in multidrug-resistant acinetobacter baumannii strains and determination of plant extract effects on multidrug-resistant isolates
Saral, Ayşegül; Cinemre, Sedanur; Okumuş, Funda; Akar, Zeynep; Çiçek, Ayşegül Çopur; Düzgün, Azer Özad
This study aimed to investigate the presence of resistance genes in multidrug-resistant A. baumannii isolates as well as to determine the antibacterial activity of selected plant extracts against isolates. 41 strains were isolated from various clinical samples. PCR tests were performed using the primers. Methanol was used as solvent for the preparation of the plant extracts. MIC values of the plant extracts were determined by the broth microdilution method. The blaOXA-23, blaCTX-M-1, blaCTX-M-2, blaGES genes and Class 1 integrons were detected in five isolated strains. The lowest MIC value (2.25 mg/mL) was determined for the Echinacea purpurea extract, while the highest MIC value (50 mg/mL) was determined for the Morus alba extract. Determination of the antibacterial effect of plants extracts used in the study against A. baumannii isolates shows the importance of screening the antibacterial activity of plants in the fight against antibiotic resistance.
- MakaleAçık Erişim2020Can an abts antioxidant test be performed without a spectrophotometer?
Burnaz, Nesibe Arslan; Akar, Zeynep
ABTS• + (2,2-azinobis- (3-ethylbenzothiazoline-6-sulphonic acid)) radical scavenging assay iswidely used to determine the antioxidant activity of natural and synthetic substances. As otherantioxidant activity determination methods, a spectrophotometer device is needed to determinethe numerical value of the color formed in ABTS method. Therefore, the dependence on thedevice is disadvantageous due to especially the high cost and restriction of workspace. Toovercome this disadvantage, a new colorimetric method in the determination of antioxidantactivity for ABTS method was developed with the help of a scanner device and free software(Image J). Mixtures (plant extracts and antioxidant standards) in this new colorimetric methodwere prepared as in the spectrophotometric method and, after the incubation period, each ofthese reagent mixtures was dropped onto the thin layer chromatography (TLC) plate. Then thecolors that appeared on the thin layer chromatography were transferred to the computer withthe help of a scanner and CSC50 values (the color value of the antioxidant concentrationrequired to scavenge 50% of the ABTS radical in the test solution using Image J software)were measured with free software of Image J. The same measurements were performedsimultaneously on the spectrophotometer. The results of both methods were compared. Therewas a strong correlation between the new colorimetric method and the spectrophotometricmethod for ABTS. Thus, the new colorimetric method for the ABTS test has become easilyapplicable since no spectrophotometer device is needed and in all environments.
- MakaleAçık Erişim2020RP-HPLC-UV Analysis of the Phenolic Compounds, Antimicrobial Activity Against Multi-Drug Resistant Bacteria and Antioxidant Activity of Fruit and Seed of Diospyros lotus L.
Akar, Zeynep; Karakurt, Aylin; Okumus, Funda; Cinemre, Sedanur; Duzgun, Azer Ozad; Akar, Bulent; Can, Zehra
The object of the present study was to investigate the antioxidant, antimicrobial activity and phenolic compounds of fruit and seeds of Diospyros lotus L. The fruits consumed by humans as nutrients were harvested from the plants that grow naturally in the province of Trabzon-Akçaabat, Eastern Black Sea Region of Turkey. The antioxidant activities of fruit and seeds of Diospyros lotus were determined by using four methods (% DPPH radical scavenging activity, FRAP antioxidant power determination, CUPRAC reducing antioxidant activity and total phenolic content (TPC) in five different proportion of methanol-water extracts. All extracts of fruit and seeds of D. lotus analyzed through whole antioxidant analysis methods showed significant antioxidant activity. In addition, antimicrobial activity of fruit and seeds extracted with DMSO was determined against seven standard bacteria and three multi-drug resistance clinical strains. Although fruit extracts did not have the antimicrobial activity against bacteria, seeds showed antimicrobial effect to both standard strains (Gram-negative and Gram-positive) and antibiotic resistance clinical isolates (Klebsiella pneumoniae carrying blaKPC, Acinetobacter baumannii, harboring blaOXA-23 gene and resistance to colistin, and multi-drug resistant Pseudomonas aeruginosa). MICs’ value of plant seed extracts for standard strains was 0.75-25 mg/mL and antibiotic resistant clinical bacteria were 12.5 and 25 mg/mL. Additionally, phenolic compounds in methanol extracts of fruit and seeds were also determined in by HPLC using 19 standards. Gallic acid and chrysin phenolic compounds were the major phenolic compounds in fruit and seeds, respectively.
- MakaleAçık Erişim2020Biological activities and phytochemical screening of ethanol extracts from adonis paryadrica (Ranunculaceae)
Ucuncu, Osman; Baltaci, Cemalettin; Akar, Zeynep; Duzgun, Azer Ozad; Cuce, Mustafa; Kandemir, Ali
In this study, secondary metabolite profiles of flower, leaf and root of Adonis paryadrica ethanolic extracts were performed by using a newly developed and validated LC-MS/MS method. For this purpose, the LC-MS/MS system was used for the quantitative and qualitative analysis of 37 phytochemicals. The main component of the flower, leaf and root extracts was the quinic acid (160, 111 and 64 mg/kg, respectively). Antioxidant activities were determined using methods such as DPPH (SC50, mg/mL), FRAP (µM TEAC), CUPRAC (µM TEAC), ABTS (SC50, mg/mL) and TPC (GAE, µg/mL). While the highest antioxidant activity value for FRAP, CUPRAC, ABTS and TPC methods was determined in the leaf part of the plant, this value was determined in the flower part for DPPH. The antibacterial effects of the plant extracts were determined by liquid microdilution and agar diffusion methods. As a result, antimicrobial effect of flowers, leaf and all sections of plant extracts were determined except plant root extracts which did not display any activity against bacteria. Antimicrobial activity of the plant flower extract was found to be higher especially against to P. vulgaris with 3.5 mg/mL MIC.
- MakaleAçık Erişim2019Identification of Antioxidant Activity by Different Methods of a Freshwater Alga (Microspora sp.) Collected From a High Mountain Lake
Akar, Zeynep; Akar, Bülent; Şahin, Bülent
Algae contain a large amount of biological active compounds functioning as antioxidant,antimicrobial and anti-tumour. In the present research, antioxidant activity of freshwateralga Microspora sp. (Chlorophyta) extract prepared in different solvents (methanol,acetonitrile, ethanol, acetone and ethyl acetate) was determined with three differentmethods; 2,2-diphenyl-1-picrylhydrazyl (DPPH•), Iron (III) Reduction / AntioxidantPower (FRAP) Assay and Copper (II) Reductive Antioxidant Activity (CUPRAC). Thealga samples collected from the high mountain lake (2733 m above sea level) localized inGümüşhane province of Turkey. The algal extracts prepared in different solvents showedantioxidant activity. The values of DPPH• varied from 8.97% (in acetonitrile extract) to31.15% (in methanol extract). As in the DPPH• method, the lowest and highest values inthe FRAP method were measured based on μM TEAC (Trolox Equivalent AntioxidantCapacity) in methanol and acetonitrile extracts as 60.303 μM and 359.394 μM respectively.While the lowest value of CUPRAC test was determined in acetonitrile extract (0.041 μMTEAC ) as in the other tests, highest value was measured in ethanol extract (0.101 μMTEAC ). The values of highest antioxidant activity in both DPPH• and FRAP methodswas measured in the methanol solvent whilst was determined in the ethanol solvent forCUPRAC.
- MakaleYalnız künye2019DETERMINATION OF ANTIOXIDANT, ANTIMICROBIAL ACTIVITIES, PHENOLIC COMPOUNDS OF WILD ROSA L. SPECIES BAYBURT, TURKEY
Gidik, Betul; Akar, Zeynep; Can, Zehra; Sefali, Abdurrahman; Erturk, Omer
Five different rosehip (Rosa L.) species including, Rosa canina, Rosa iberica Stev, Rosa villosa, Rosa beggeriana Schrenk and same kind of but different location Rosa spinosissima grown in Bayburt from Turkey are studied. The wild species of Rosa L. were collected from Rocks and Steps, Field and garden borders. Morphological parameters were measured as fruit and seed weights and fruit and seed size. Ten fruits were chosen randomly for the measurement and take the average of them to determine the weights and size. In our study was determined antioxidant activity, antimicrobial activity and phenolic compounds. As antioxidant activity; total phenolic total flavonoid, condense tannin contents, CUPRAC, FRAP, ABTS. Nineteen standard of phenolic compositions of fruits and seeds were determined. Antioxidant, antimicrobial activities of the extracts were found high levels in rose hip species fruit than seed. Catechin, rutin protocatequic acid and CAPE were principal for all rose hip species fruit but, was not deteceted CAPE Kop Mountain, Yukari Kop Village Rosa spinosissima species. This suggests that the difference in location affects the phenolic content. Pearson Correlation analyze has done with the morphological parameters, GPS data, antioxidant activity and phenolic compounds by using the SPSS software programme version 25.0.