Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Now showing 1 - 8 of 8
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Enhancing the Sustainable Protein Extraction Process From Black Cumin Seed Cake Press for Eco-Friendly Protein Supplements
    (Springer Science and Business Media Deutschland GmbH, 2025) Ammas, B.; Uzuner, Sibel; Uzuner, S.
    Finding new protein sources is essential to meet the global population’s needs. Nigella sativa (black cumin) seeds and the residual cake left after oil cold pressing contain valuable nutritional compounds, including proteins, phenolics, essential amino acids, and various bioactive compounds. In the literature, the structural characteristics and functional properties of proteins from black cumin seeds have been extensively studied. However, there are limited reports on the use of emerging extraction technologies for extracting soluble proteins from black cumin seed cake press (BCSCP). Therefore, two distinct extraction techniques—microwave (MW) and ultrasonication (US)—were assessed for their effectiveness in extracting soluble proteins from BCSCP. The aim of this study was to investigate the effects of various operational conditions on protein extraction yield and functional properties of proteins extracted from BCSCP. The maximum protein yield (27.04%) was achieved using a 10% solid/liquid ratio (SLR) at 33 °C for a 30-min extraction time with the US extraction technique. After ultrafiltration, the protein yield increased to 33.83%, showcasing the predominance of sarcosine (17.18 g/100 g), glutamine (11.63 g/100 g), and proline (33.46 g/100 g) amino acids. The water-holding capacity (WHC), oil-holding capacity (OHC), foam capacity (FC), and foam stability (FS) of the BCSCP isolate were found to be 5.4 ± 0.3 g/g, 9.4 ± 0.0 g/g, 43.6 ± 6.4%, and 39.0 ± 4.7%, respectively. The study revealed that US is a suitable extraction process for obtaining soluble proteins from BCSCP with favorable functional properties. Further studies are needed to evaluate the bioavailability and health impacts of bioactive peptides in order to develop food applications. © The Author(s) 2024.
  • Article
    Citation - Scopus: 2
    A Comparative Assessment for Efficient Oleuropein Extraction From Olive Leaf (olea Europaea L. Folium)
    (Murat Yakar, 2023) Recepoğlu, Yaşar Kemal; Gümüşbulut, Gülin; Yüksel Özşen, Aslı
    Since oleuropein has long been known in the health sector and is abundant directly in our country as the fourth largest olive producer, oleuropein, the predominant phenolic ingredient in olive leaves, was recovered in this study using Soxhlet extraction. The effects of different solvent types (acetonitrile, ethanol, methanol, and water), extraction period (4 cycles, 4 h, and 8 h), particle size (250-500 µm and 900-2000 µm), and pretreatment of olive leaves on the yield of oleuropein were examined to determine the maximum yield. A greater oleuropein yield was obtained when the particle size of olive leaves utilized for extraction was lowered. Furthermore, aqueous solvents revealed a higher yield of oleuropein than pure solvents and prolonging the extraction duration resulted in a significant increase in the amount of oleuropein extracted. On the other hand, pretreatment of olive leaves resulted in a reduction in oleuropein output. As a result, with 36% extraction efficiency in terms of olive leaf conversion, the highest oleuropein extraction yield was obtained as 13.35 mg g-1 dry leaf for 8 h of extraction time using olive leaves with a particle size of 250-500 µm and an 80% methanol solution as solvent. © Author(s) 2023.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 10
    Removal of Pesticide Residues From Apple and Tomato Cuticle
    (Springer, 2023) Tari, Vinaya; Yalçın, Melis; Turgut, Nalan; Gökbulut, Cengiz; Mermer, Serhan; Sofuoğlu, Sait Cemil; Turgut, Cafer
    Pesticide residues are always an unsolved problem in the world despite all kinds of prevention measures. The present research work is based on a scientific hypothesis, i.e., The removal of average pesticide residue is inversely proportional to the thickness of cuticle. The effects of boron-containing products and plant-based surfactants were tested for the removal of five pesticides (lambda-cyhalothrin, chlorpyrifos, diflubenzuron, metaflumizone, acetamiprid) on tomatoes and apples. Boron-containing products were able to remove the pesticide residues on average between 58.0 and 72.6% in tomatoes and 33.2-58.8% in an apple. While plant-based surfactants removed residues on average between 58.5 and 66.6% in tomatoes and 41.0-53.2% in an apple. The highest removal rate was 72% with etidot at 1%. The solution of 1% C8-C10 provided 66.6% average removal for tomatoes. Less removal was achieved in apples. For an apple, Log K-ow and molecular mass (independent variables) were significant with p < 0.01, and the coefficient of determination (R-2) was > 0.87. However, the multiple linear regression analysis for ground colemanite was significant with R-2 of 0.96. In tomatoes, neither Log K-ow nor molecular mass as significant. The correlation was found between the physical and chemical properties of pesticides, but it is estimated that the thickness of the cuticle is effective in removing pesticides.
  • Article
    Citation - WoS: 45
    Citation - Scopus: 46
    Electrospun Polystyrene Fibers Knitted Around Imprinted Acrylate Microspheres as Sorbent for Paraben Derivatives
    (Elsevier, 2018) Demirkurt, Merve; Ölçer, Yekta Arya; Demir, Mustafa Muammer; Eroğlu, Ahmet Eroğlu
    Parabens are used as antimicrobial preservatives in food, cosmetic products and pharmaceuticals regardless of their endocrine disrupting effect. In this study, highly selective molecular imprinted polymers (MIPs) were synthesized in submicron-sizes and converted to an SPME fiber coating through electrospinning process in order to determine parabens in water samples. Conversion of MIP to a fiber is achieved via creation of spacial knitting around MIP by polystyrene. The selectivity and extraction ability of the fibers were compared with the commercial fibers and the corresponding non-imprinted polymer (NIP) coated fiber. The coated fiber showed better extraction ability among them. Also, the results revealed that the fiber has better selectivity for benzyl paraben and the other structurally-related compounds, such as methyl and propyl paraben. Extraction efficiency of prepared fibers for three parabens has been tested by spiking bottled, tap and sea water samples. The recoveries changed between 92.2 ± 0.8 and 99.8 ± 0.1 for three different water types. This method could be used for selective and sensitive determination of parabens in aqueous samples.
  • Article
    Citation - WoS: 12
    Citation - Scopus: 16
    Carotenoid Profile in Prochlorococcus Sp. and Enrichment of Lutein Using Different Nitrogen Sources
    (Springer Verlag, 2016) Erdoğan, Ayşegül; Demirel, Zeliha; Eroğlu, Ahmet Emin; Conk Dalay, Meltem
    Various carotenoids of the cyanobacterium Prochlorococcus sp. are identified using chromatographic/spectroscopic techniques and quantified using HPLC-DAD. In the present study, β-apo-8′-carotenal was used as internal standard. Identification of carotenoids was carried out by comparing the retention time, absorption spectra, and mass spectra of unknown peaks with reference standards. All-trans-lutein was found to be the major carotenoid in this cyanobacterium, and, therefore, algal productivity and the potential for lutein accumulation were analyzed as a function of different nitrogen sources such as nitrate, nitrite, ammonia, and urea for cultivation. Among them, urea clearly led to the best lutein accumulation. According to the experimental evidence, lutein increased from 2.54 to 3.34 mg g−1 in the cyanobacteria when urea was used as the nitrogen source. © 2016, Springer Science+Business Media Dordrecht.
  • Article
    Citation - WoS: 20
    Citation - Scopus: 24
    Preparation and Characterization of Sodium Dodecyl Sulfate Doped Polypyrrole Solid Phase Micro Extraction Fiber and Its Application To Endocrine Disruptor Pesticide Analysis
    (Elsevier Ltd., 2013) Korba, Korcan; Pelit, Levent; Okçu Pelit, Füsun; Özdokur, K. Volkan; Ertaş, Hasan; Eroğlu, Ahmet Emin; Ertaş, Fatma Nil
    A robust in house solid-phase micro extraction (SPME) surface has been developed for the headspace (HS)-SPME determination of endocrine disruptor pesticides, namely, Chlorpyrifos, Penconazole, Procymidone, Bromopropylate and Lambda-Cyhalothrin in wine sample by using sodium dodecylsulfate doped polypyrrole SPME fiber. Pyrrole monomer was electrochemically polymerized on a stainless steel wire in laboratory conditions in virtue of diminishing the cost and enhancing the analyte retention on its surface to exert better selectivity and hence the developed polymerized surface could offer to analyst to exploit it as a fiber in headspace SPME analysis. The parameters, mainly, adsorption temperature and time, desorption temperature, stirring rate and salt amount were optimized to be as 70°C and 45min, 200°C, 600rpm and 10gL-1, respectively. Limit of detection was estimated in the range of 0.073-1.659ngmL-1 for the pesticides studied. The developed method was applied in to red wine sample with acceptable recovery values (92-107%) which were obtained for these selected pesticides.
  • Article
    Citation - WoS: 18
    Citation - Scopus: 22
    Fucoxanthin Content of Cylindrotheca Closterium and Its Oxidative Stress Mediated Enhancement
    (Central Fisheries Research Inst, 2016) Erdoğan, Ayşegül; Demirel, Zeliha; Conk Dalay, Meltem; Eroğlu, Ahmet Emin
    Production of fucoxanthin by diatoms has become an alternative research area due to their low cost, convenience and diversity. The fucoxanthin content of Cylindrotheca closterium and its enhancement by altering the cultivation conditions via oxidative stress were investigated in this study. For this purpose, the extraction parameters were optimized and the highest fucoxanthin concentration (6.58 mg g-1) was achieved within 15.0 minutes at 40 °C. Then, this yield reached to 10.15 mg g-1 in the presence of NaOCl and Fe2+. It is worth noting that, this is the first time that the effect of oxidative stress on fucoxanthin production in diatom has been studied according to our knowledge. Therefore, the results of this study and the discussion about the mechanisms can be a reference for the enrichment of fucoxanthin from other diatoms.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 3
    Recovery of Proanthocyanidin From Waste of Turkish Traditional Product, Pekmez (molasses)
    (Japanese Society for Food Science and Technology, 2007) Altıok, Evren; Ülkü, Semra; Ülkü, Semra; Ülkü, Semra; Bayraktar, Oğuz; Bayraktar, Oğuz; Bayraktar, Oğuz
    The possibility of recovering of proanthocyanidin (PA) from the by-product of Turkish traditional product pekmez (molasses) industry, one of the agro industries, was investigated. In order to obtain optimum extraction conditions, the effects of different solvents and their aqueous forms were studied and the highest PA concentration was achieved as 31 (±0.68)g/L with acetone/water (30: 70, v/v) solution. The correlations between phenolic contents, PA concentrations and antioxidant capacities were shown. Antioxidant capacities of extracts were determined and the comparison of them with synthetic and commercial antioxidants was performed. The antioxidant capacity of PA extract from grape seed of molasses pomace was 93 (±1.43) TEAC values, which was relatively high compared with those of the synthetic antioxidants. Silk fibroin was used as a novel adsorbent to recover the PA from the grape seed extracts. Effect of parameters such as, solid-liquid ratio, pH and initial concentration of PA on the recovery performance was investigated. All parameters were found statistically significant parameters (P < 0.005) and the best adsorption conditions were found to be pH 5.5, initial concentration as 10 g/ml and solid-liquid ratio as 0.1 g/ml, which yielded the maximum percentage of adsorbed PA amount as 85.2%.