Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Uzun, Sevda(62)
- Merdan, Mehmet(58)
- Duran, Celal(50)
- Ozdes, Duygu(47)
- Kaygusuz, Abdullah(43)
- Ashyralyyev, Charyyar(38)
- Karsli, Orhan(33)
- Öztürk, Serkan(32)
- Araz, Onur(31)
- Demir, Selim(29)
- Kulakaç, Nurşen(29)
- Dokuz, Abdurrahman(28)
- Arslan, Mehmet(27)
- Baltacı, Cemalettin(27)
- Maden, Nafiz(27)
- Sipahi, Ferkan(27)
- Topal, Fevzi(27)
- Turan, Ibrahim(27)
- Kandemir, Raif(25)
- Kurt, Kemal(24)
- Ozturk, Samet(24)
- Peker, Iskender(24)
- Vural, Alaaddin(24)
- Reis, Hatice Catal(23)
- Yücel, Cem(23)
- Aydin, Faruk(22)
- Baltaci, Cemalettin(22)
- Gücer, Mehmet Ali(22)
- Günen, Mehmet Akif(22)
- Kankal, Murat(22)
- Topal, Meryem(22)
- Karimullah, Suud Sarim(21)
- Uysal, Ibrahim(20)
- Kurnaz, Muammer(19)
- Tuncer, Metin(19)
- Yolcu, Halil(19)
- Çelik, Necati(19)
- Ürkek, Bayram(19)
- Şan, Murat(19)
- Aliyazicioglu, Yuksel(18)
Yayınlar
- MakaleYalnız künye2021Scopus SJRQ1A reduced variance unsupervised ensemble learning algorithm based on modern portfolio theory
Ünlü, Ramazan; Xanthopoulos, Petros
Unsupervised ensemble learning or consensus clustering has gained popularity due to its ability to combine multiple clustering solutions into a single solution that is robust and often performs better than the individual ones. There have been several approaches to consensus clustering including voting and weighted voting algorithmic schemes. Although there have been several algorithms for adjusting the weights of a consensus clustering all of them are tuned based on some performance characteristic associated with clustering accuracy. In this paper, we propose a method for incorporating weights by taking into consideration the intra algorithmic variability i.e. algorithms that provide solutions with very different performance upon multiple runs. The methodology is inspired by modern portfolio theory and more specifically from Markowitz model for asset allocation where one is trying to identify the most efficient portfolio through the solution of a convex optimization problem. Here, efficiency is defined as the minimum amount of risk for an expected return. We apply this method to different datasets and compare with respect to performance and robustness. The proposed scheme appears to achieve competitive average performance with very low variability.
AtıfScopus13WoS7OpenAlex15
İncele - MakaleAçık Erişim2021Scopus SJRQ4Quadrotor Flight System Design using Collective and Differential Morphing with SPSA and ANN
Kose, Oguz; Oktay, Tugrul
Quadrotor modeling has been done with collective and differential morphing. Quadrotor initial state and morphing states are drawn in the Solidworks program. Newton-Euler approximation was used for quadrotor modeling. The mass and moment of inertia values required for modeling and simulation were obtained from the Solidworks program. Matlab / Simulink environment and state-space model approaches are used for simulations. A simultaneous perturbation stochastic approximation (SPSA) algorithm was used to determine the quadrotor morphing rates. If the morphing state obtained by SPSA is not included in the values obtained from the drawings, here it is provided to find the moments of inertia with the method based on learning by using the data obtained with the Artificial Neural Network(ANN). Proportional Integral Derivative (PID) is used as the quadrotor control algorithm. PID coefficients are also determined by SPSA.
AtıfScopus13OpenAlex13
İncele - MakaleYalnız künye2021The Relationship between Body Mass Index and Eating Disorder Risk and Intuitive Eating among Young Adults
Yılmaz, Hacı Ömer; Zemzemoglu, Tuba Eda Arpa
Background: Obesity is a serious health problem that threatens public health. There are limited researches exploring the relationship between obesity and eating disorder risk and intuitive eating. The purpose of this study was to determine the rate of eating disorder risk and obesity, and identify the relationship between body mass index (BMI) and eating disorder risk and intuitive eating among young adults. Methods: This cross-sectional study enrolled 1216 young adults. The data were obtained through a questionnaire consisted of three sections of socio-demographic information in the first part, Intuitive Eating Scale-2 (IES-2) in second part and Eating Attitudes Test-26 (EAT-26) in third part. Weight, height, and BMI of participants were also measured by researchers. Results: The overall overweight/obesity rate of the participants was 16% (male=25.9%; female=10.9%). The rate of eating disorders risk was 24.3% in general (male=21.5%; female=25.4%). Overweight/obese had higher eating disorders risk than normal and underweight (26.7%, 23.8%, 21.6%, respectively). IES-2 score of underweight was significantly higher than overweight/obese (3.33±0.35, 3.20±0.37, respectively). Conclusion: This is the first study to examine the relationship between BMI and EAT-26 subscale showing that BMI was positively correlated with EAT-26 and negatively was correlated with IES-2 score. Therefore, BMI may be affected by eating behaviors and intuitive eating. Also, intuitive eating can be a new method of eating, and weight control and management.
AtıfScopus11OpenAlex7İncele - Kitap BölümüYalnız künye2021Pandemic transaction cost and impact on the economy
Çiçen, Yildirim Beyazit
- MakaleYalnız künye2021Scopus SJRQ1A rapid method to detect green pea and peanut adulteration in pistachio by using portable FT-MIR and FT-NIR spectroscopy combined with chemometrics
Aykas, Didem Peren; Menevseoglu, Ahmed
In this research, the determination of green pea and peanut adulteration in pistachio by portable Fourier transform mid-infrared (FT-MIR) and Fourier transform near-infrared (FT-NIR) spectroscopy was studied. A rapid method to detect adulteration in pistachio is a necessity in the food industry because of its high commodity value and being one of the most consumed tree nuts. Pistachio nut is a target for economically motivated adulteration, and green pea, spinach, and peanut are the most seen adulterants in pistachio. Portable FT-MIR and FT-NIR spectrometers are simple, non-invasive, rapid, easy to transport, and cheaper alternatives to traditional methods, including chromatography (GC, HPLC), mass-spectroscopy (GC-MS, LC-MS) for the detection of pistachio adulteration. Powdered pistachio samples were adulterated with powdered green pea and peanut samples at different concentrations (5–40%). Spectra were collected with a portable FT-MIR and FT-NIR spectrometers and analyzed by Soft Independent Modeling of Class Analogy (SIMCA) to generate a classification model to authenticate pure pistachio, and Partial Least Square Regression (PLSR) to predict the levels of adulterants in pistachio. SIMCA provided, in both units, very distinct clusters for pure and adulterated samples with inter-class distance (ICD) over 3. Both units also showed superior performance in predicting adulterant levels with rVal>0.99, standard error of prediction (SEP) < 2.5%. Based on SIMCA and PLSR models, portable FT-NIR spectrometer provided more advantages over portable FT-MIR unit because the prediction with the FT-NIR spectrometer was more precise than the FT-MIR unit. Both portable FT-MIR and FT-NIR units can be used as alternative methods to traditional methods and showed great potential for real-time surveillance to detect green pea and peanut adulteration in pistachio.
AtıfScopus70WoS60OpenAlex71İncele - Kitap BölümüAçık Erişim2021Investigation of the foreign direct investment and environmental pollution nexus for developing countries
Çelik, Orkun; Korkmaz, Özge; Adalı, Zafer
In theory, the foreign direct investment and environmental pollution nexus is explained by three hypotheses. Firstly, pollution haven hypothesis assumes that there is a positive nexus between these variables. Secondly, pollution halo hypothesis supposes that there is negative connection between these variables. Lastly, neutrality hypothesis asserts the non-existence of the connection between these variables. In recent years, many researchers have frequently tested whether these hypotheses are valid for different countries. In this study, applying Westerlund panel cointegration test, the authors aim to explore the nexus between foreign direct investment and environmental pollution for 23 developing countries after global crisis. For this aim, they use annual data covering the period 2009-2019. According to the obtained empirical findings, the presence of the long-term nexus between foreign direct investment and environmental pollution is not detected for 23 developing countries. Accordingly, the authors can say that there is neutrality hypothesis.
AtıfScopus1OpenAlex4İncele - MakaleYalnız künye2021Scopus SJRQ2Determining 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.
AtıfScopus18WoS21OpenAlex17İncele - MakaleYalnız künye2021Scopus SJRQ1Additivity effect on properties of cemented coal fly ash backfill containing water-reducing admixtures
Cavusoglu, Ibrahim; Yilmaz, Erol; Yilmaz, Ali Osman
Cemented coal fly ash backfill (CCB), a flowable structure of coal fly ash, binding agent and mixing water, has been often employed in mining operations to offer ground support as well as waste disposal solutions. An appropriate CCB mass should have sufficient rheological (e.g., workability) and mechanical (e.g., strength and stability) characteristics. Chemical admixtures are well known to greatly enhance the pumpability and strength properties of cementitious materials. Thus, this work provides the effect of water-reducing admixtures (namely, Sikament MR 50 W and Sikament FFN) on characteristics of CCB materials manufactured at a constant slump value. The role of admixtures in CCB mix is to reduce the cement-related costs, to modify the properties of the hardened backfills, and to ensure the quality of the backfill during mixing, transporting, placing, and curing. These admixtures were used at a dosage of 1% and 2% by weight of anhydrous material on cement. Several laboratory tests including slump, setting time, uniaxial compressive strength, scanning electron microscopy and mercury intrusion porosimetry were undertaken on CCB samples to understand their fresh and hardened performance. Experimental results show that the admixtures used ensure the slump required to deliver CCB at low water/cement ratios, improve short- and long-term backfill strengths up to 33%, and decrease the total porosity of the tested CCB. The findings of this study also show that the admixture use in CCB leads to a significant decrease in the considered cement content and a remarkable increase in the mechanical strength. As a result, understanding the actual fresh and hardened properties of CCB remains crucial for the choice of the greatest acting backfill admixture and for a fruitful change from capable experimental results to the in-situ conditions.
AtıfScopus76WoS69OpenAlex78İncele - MakaleAçık Erişim2021Fuzzy inverse logic: part-2. validation and evaluation of the method; [Bulanık ters mantık: kısım-2. yöntemin doğrulanması ve değerlendirilmesi]
Öztekin, Ertekin
In the first part of this study, which consists of two parts, the introduction of the fuzzy inverse logic method, its foundations, computation and process flow and details were given. In this second part, the method was applied on a very simple mathematical problem and on a simple civil engineering design problem in order to investigate and evaluate the validity of the method easily. Fuzzy inverse logic computations have been carried out on these two simple problems for different dimension, sensitivity and acceptable error values. By comparing the obtained results with the desired outputs and mathematical results, the effective computation ability of the method was tried to be revealed. As a result, it is understood that the method developed in this study has many promising aspects in terms of theoretical computations and practical applications and can be used effectively in many scientific fields.
AtıfScopus2OpenAlex3TR Dizin1İncele - MakaleYalnız künye2021Scopus SJRQ1Particle Erosion Performance of Additive Manufactured 316L Stainless Steel Materials
Azakli, Zeki; Gümrük, Recep
Many critical parts such as surface parts of high-speed trains, bins and hoppers, and pipes, bends and valves in material transportation applications as well as a helicopter, mixer, and turbine blades, which can be exposed to particle wear due to the application environment, can be easily manufactured today due to the advances in 3D printing technology. For this reason, an experimental study was carried out to determine the particle erosion behavior of 316L stainless steel parts built by the laser melting method, which is one of the 3D printing technologies. The rectangular plate samples produced with various laser manufacturing parameters were subjected to particle erosion tests at different impingement angles in accordance with the ASTM G76 standard at 140 m/s impact speed. The results showed that the erosion behavior develops in a characteristic similar to the wrought sample, and laser parameters play an efficient role. For example, the porosity ratio decreases at low scanning speeds, resulting in significant improvements in erosion behavior. Also, it was found that the particle erosion behavior of the 3D printed parts could be improved in a serious amount by applying a heat treatment process. Consequently, the obtained results in this study promotes the more comprehensive works regarding the optimization of several laser manufacturing parameters such as scan speed, build direction, laser power, hatch spacing, layer thickness, scan strategy and laser exposure time to obtain the best particle erosion behavior and determination of the most suitable materials among the several others which can be used in 3D printing.
AtıfScopus19WoS17OpenAlex17İncele - MakaleYalnız künye2021Scopus SJRQ3Determination of the Chemical Composition, Antioxidant and Antimicrobial Activities of Different Parts of Rosa canina L. and Rosa pimpinellifolia L. Essential Oils
Öz, Mehmet; Deniz, Ilhan; Okan, Onur Tolga; Baltaci, Cemalettin; Karatas, Seyda Merve
Today, the use of essential oils is increasing day by day, and it is considered as raw materials in many industries. Therefore, this study aims to identify the essential oil profile, antioxidant and antimicrobial activity of Rosa canina L. and Rosa pimpinellifolia L. reveal their potential use in the industry. Essential oils that were obtained in 2013-2014 from different parts (flower, leaf, stem, and fruit) of Rosa canina L. and Rosa pimpinellifolia L. by the hydro-distillation method were analyzed by GC/MS. The dominant components in Rosa canina L. were found as trans-geraniol in the flowers (42.08 % for 2013), linalool in the leaves (11.55 % for 2014), and stem (14.91 % for 2013) and vitispirane in the fruits (37.19 % for 2014). The dominant components in R. pimpinellifolia L. were found as heneicosane in the flowers (22.07 % for 2014), γ-elemene in the leaves (30.21 % for 2013), linalool in the stem (14.76 % for 2013) and the fruits, (E)-2-hexenal for those collected in 2013 (14.09 %). The IC50 and FRAP values of the samples ranged from 127.54 to 142.22 μg/g and 121.43 to 296.78 μmol TE/g, respectively. According to the results obtained, both R. canina L. and R. pimpinellifolia L. were found to show poor antioxidant values of DPPH and FRAP. In general, it was determined that the essential oils obtained from different plant parts of both species had a moderate antimicrobial effect against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, and Pseudomonas aeruginosa.
AtıfScopus17WoS16İncele - MakaleYalnız künye2021Scopus SJRQ4Chemical composition and biological activities of volatile oils of arabis alpina l. Ssp. alpina
Ucuncu, O.
This work reports volatile constituents, antimicrobial and antioxidant activity of volatile oils from the air-dried flower and aerial parts (APs) of Arabis alpina L. ssp. alpina. The volatile components of flower and aerial parts (stem + leaf) were investigated by means of hydrodistillation in Clevenger type apparatus and GC/MS/FID analysis. Fifty-one and fifty-three compounds in the volatile oils of flower and APs of A. alpina were identified. Terpene derivatives were the major volatiles in both oils. Hexahydrofarnesyl acetone was the main component of flower oil and APs oil in ratios of 16.27% and 26.94%, respectively. Additionally, both flower and APs essential oils were investigated for their antimicrobial activity against twelve bacteria and five fungi, using agar dilution method and antioxidant activities by using DPPH˙, ABTS˙+ and Folin-Ciocalteu assays. Flower oil was effective against B. subtilis and B. cereus even at 100µg/mL. The amount of total phenolic, %DPPH˙ scavenging activity and ABTS˙+ scavenging activity were found as 485.60±7.28 mg/mL GAE, 49.85±1.22% and 166.43±12.05µM Trolox equivalent, respectively. Flower oil exhibited antimicrobial effect against gram positive bacteria especially, and moderate antioxidant activity.
AtıfScopus3WoS2İncele - Kitap BölümüYalnız künye2021Environmental Policies, Climate Change Perception and Trust
Ugur, Candan Yılmaz
- MakaleYalnız künye2021Scopus SJRQ1The Effect of Progressive Muscle Relaxation Exercises on Pain on Patients with Sickle Cell Disease: Randomized Controlled Study
Kazak, Aysun; Ozkaraman, Ayse
Purpose: The study aimed to evaluate the effect of progressive muscle relaxation exercises on pain in patients with sickle cell disease. Materials-Method: This randomized controlled interventional study was conducted in a hospital in Mersin, Turkey between October 2017 and July 2018. The study sample comprised 58 patients who were aged >18 years, conscious, had sickle cell disease, reported pain, and were treated with non-opioid or weak opioid analgesic based on the physician's recommendation (treatment group = 29, control group = 29). Data were collected by the individual presentation form and visual analog scale. During the study, both groups were treated with analgesics prescribed by the physician for three days. In addition to the analgesics, the treatment group was performed progressive muscle relaxation exercises for 30 minutes whereas the control group was rested. Pain level of both groups was evaluated at three time points every day for three days. In the study, frequency distributions and descriptive statistics were presented for categorical and numerical variables, respectively. Chi-square analysis, independent samples t-test, Mann–Whitney U test, three-way ANOVA, and Sidak test were used to analyze the difference between the variables. Results: The mean age of the patients was 29.59 ± 6.94 years, and 53.4% of the patients were female and 69% were single. The mean pain score of the treatment group at the third time point on days 1, 2, and 3 was significantly lower than the control group (p <.05). There was no statistically significant difference between the two groups in terms of coping methods for pain, pain location, and complaints accompanying pain (p >.05). Conclusion: Progressive muscle relaxation exercises were found to be effective in the pain management of patients with sickle cell anemia.
AtıfScopus7WoS5OpenAlex16
İncele - Kitap BölümüYalnız künye2021Chingiz Aitmatov's grand narrative
Çakin, Ömer; Günay, Mehmet Akif
Beyond political and cultural criticisms, grand narratives have the authority to disclose real facts. This authority is most effective in the field of culture. Grand narratives are the universal presentation of local culture. In a culture dominated by grand narratives, the dominant ideology of the regime is to control knowledge. Grand narratives play a role in generalizing and transferring information skillfully while describing the contemporary situation. A novelist was defined as a mirror reflecting the period and society in which he lived. Likewise, Chingiz Aitmatov tried to depict the political, social, and cultural structure of his period, and accordingly, formed his own grand narrative. The author skillfully revealed the facts of the period regarding the Marxist tradition and described the social, cultural, and political structure of the period using a tentative language in parallel with the facts such as analogy, myth, and legend.
AtıfScopus1İncele - MakaleYalnız künye2021Contribution to the taxonomic knowledge of acanthodactylus (Squamata, lacertidae): Description of a new lacertid lizard species from eastern anatolia, turkey
Kurnaz, Muammer; Şahin, Mehmet Kürşat
Acanthodactylus Wiegmann, 1834 is one of the most diverse and widespread lizard genus in the Palearctic realm. Here, we describe a new species, - Acanthodactylus ilgazi sp. nov. - from the Anatolian Peninsula. This new species ranges approximately 250 km north from the closest population of this genus in Turkey. Compared to other fringe-fingered lizards, the new species is phylogenetically close to A. robustus, A. tristrami and A. orientalis but it has some distinct morphological characteristics: Reddish coloration under the tail, a sharp white or grayish stripe in the middle of the dorsum, and four plates in a row on the 4th finger. Moreover, phylogenetic molecular data, based on cyt b gene fragment, verifies that the new species is phylogenetically a member of the tristrami species group with 13.03%, 17.35% and 20.56 genetic distance respectively from A. orientalis, A. tristrami and A. robustus. Lastly, the known range of this species, located in Yazıhan, Malatya in Eastern Anatolia, is restricted by a dam, thus habitat loss endangers its continuity. Therefore, the conservation status of this species should be assessed immediately.
AtıfScopus6İncele - MakaleYalnız künye2021Scopus SJRQ2From Turkey: First Report of KPC-3-and CTX-M-27-Producing Multidrug-Resistant Klebsiella pneumoniae ST147 Clone Carrying OmpK36 and Ompk37 Porin Mutations
Özad Düzgün, Azer
Aim: The aim of this study was to identify antimicrobial resistance genes, virulence factor genes, and porin loss or mutations exhibited by the multidrug-resistant Klebsiella pneumoniae strain. Materials and Methods: Whole-genome sequencing was done via the Illumina NovaSeq 6000 platform. Strain identification and antibiotic susceptibility testing of strains were performed by the Vitek 2 automated system. Multilocus sequence typing analysis was carried out using seven conserved housekeeping genes. Results: The strain was resistant to penicillins, cephalosporins, carbapenems, aminoglycosides, fluoroquinolones, fosfomycin, and trimethoprim/sulfamethoxazole. The isolate was found to carry KPC-3, CTX-M-27, SHV-11, SHV-67, and TEM-1 β-lactamases. The clonal subtype of the isolate was ST147, and it possessed wzi64 and wzc38 alleles. Fifteen different point mutations (N49S, L59V, R146H, V178P, G189T, F198Y, V202L, F207Y, A217S, T222L, D223G, H235N, A280V, N304E, and S346N) were detected in the OmpK36 porin. A frame shift was observed in OmpK35 and two different point mutations (I70M and I128M) were found in the OmpK37 porin, in addition to seven mutations observed on the AcrR. Conclusions: This study demonstrated for the first time that the ST147 clone produced CTX-M-27 as well as KPC-3. In addition, new mutations were detected in the outer membrane proteins. These mutations together with the production of extended-spectrum β-lactamase and carbapenemase were found to contribute to the resistance of the ST147 clone to carbapenem and other antibiotics.
AtıfScopus11WoS11OpenAlex9İncele - MakaleYalnız künye2021Scopus SJRQ1Mineralogical and Chemical Characteristics of Clay Areas, Gümüşhane Region (NE Turkey), and Their Detection Using the Crósta Technique with Landsat 7 and 8 Images
Vural, Alaaddin; Akpinar, İbrahim; Sipahi, Ferkan
The clay areas in Gümüşhane (NE Turkey) were examined in mineralogical and geochemical terms, and by remote sensing methods. X-ray diffraction, scanning electron microscope and chemical analysis were completed on samples from 11 selected clay areas in the region. Within the scope of remote sensing, Landsat 7 and 8 satellite images of the region were processed with the Crósta technique to assess the clay areas. The Kale and Tamzı clays are contained within a Late Cretaceous turbiditic series. The clays in Canca, Refene and Çamlıca occur in intensively hydrothermally altered volcanic rocks of the Eocene Alibaba Formation. The other clay areas are in the Liassic Şenköy Formation consisting of a volcano-sedimentary series. The clays in the Şenköy Formation are generally below the coal levels. While mainly illite and lesser kaolinite were determined in Dörtkonak, Alemdar, Yukarı Kov and Çamlıca, the clays in Tahnis and Kabantaşı are smectite. Tekke, Canca and Refene clays are kaolinite with smaller amounts of illite, whereas Kale and Tamzı clays are mainly chlorite with lower content of illite–smectite interlayers. Illites in Dörtkonak, Alemdar, Yukarı Kov and Çamlıca are poor in iron and magnesium and formed by hydrothermal alteration of feldspars in the host rocks. Findings of the remote sensing studies using Landsat 7 and 8 datasets were compatible with the results obtained from field observations and general geological studies, and so it is concluded that the Crósta technique provided good results for exploration of clay occurrences and their determination in the region.
AtıfScopus14WoS14OpenAlex15İncele - MakaleYalnız künye2021Scopus SJRQ2Biological 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.
AtıfScopus2WoS2OpenAlex3İncele - MakaleYalnız künye2021Scopus SJRQ2Preparation of melon peel biochar/CoFe2O4 as a new adsorbent for the separation and preconcentration of Cu(II), Cd(II), and Pb(II) ions by solid-phase extraction in water and vegetable samples
Ozdes, Duygu; Duran, Celal
The present research describes the successful preparation of melon peel biochar modified with CoFe2O4 (MPBC/CoFe2O4) followed by its usage as a new sorbent to separate, preconcentrate, and determine the toxic heavy metal ions by magnetic solid-phase extraction. The metal ion desorption was performed by 0.1 M HCl solution with a volume of 5.0 mL. Flame atomic absorption spectrometry (FAAS) was utilized for detection of the analyte levels. SEM–EDX, TEM, XRD, and FTIR techniques were carried out to illuminate the structure of MPBC/CoFe2O4. The fundamental variables affecting the adsorption and elution efficiencies of the analyte ions including solution pH, MPBC/CoFe2O4 amount, type and concentration of eluent, adsorption and desorption equilibrium time, and sample volume were optimized. The detection limits were calculated as 0.41, 1.82, and 3.16 µg L−1 for Cu2+, Cd2+, and Pb2+ ions, respectively, with the relative standard deviation of lower than 4.2%. There were no substantial interference effects on the analyte ion recovery due to the presence of foreign ions at high levels. Five minutes of contact time was adequate to attain the adsorption equilibrium. The adsorption capacity of MPBC/CoFe2O4 was obtained as 106.4, 65.4, and 188.7 mg g−1 for Cu2+, Cd2+, and Pb2+ ions, respectively, by utilizing Langmuir isotherm model. The pseudo-second order model is favorable to identify the adsorption kinetics. The method was validated by spike/recovery test, and then, it was successfully implemented to determine the aforementioned analyte levels in sea and stream water, pepper, black cabbage, eggplant, and tomato samples.
AtıfScopus40WoS38OpenAlex39İncele