Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 5Citation - Scopus: 6A Novel Enzymatic Delamination Method for Sustainable Recycling of Crystal Silicon Photovoltaic (c-Si Pv) Modules(Elsevier, 2025) Karagoz, Sadik Can; Gundogdu, Tugba Keskin; Sarialtin, Huseyin; Celiktas, Melih SonerDue to the growing effects of global warming, there has been a surge in the demand for renewable energy sources. In particular, the most important player in this increase is the installation of photovoltaic (PV) modules. At this critical stage, it has become a priority to identify strategic approaches for the recycling of end-of-life PV panels with a strong focus on environmental protection. This study examined the impact of enzymatic delamination on the separation of the EVA (Ethylne Viniyl Aceate Co polymer) layer, a crucial stage in the recycling process of PV panels. Notably, this investigation is the first of its kind in the existing literature. To investigate this, delamination effects of lipase, laccase, and lecitase enzymes were analyzed according to experimental design methods. Furthermore, sunflower oil was employed for the first time in the existing body of literature to facilitate delamination, resulting in a delamination rate of 100 %. The environmental impacts of these biotechnological techniques, which serve as alternatives to the commonly used toluene, were also comparatively assessed by life cycle assessment (LCA) method to analyze the environmental impact. LCA methodology was performed from gate to gate and the Recipe impact methodology was used. Oil assisted enzymatic delamination method was shown to be an alternative from environmental point of view to solvent based method such as toluene.Article Citation - WoS: 125Citation - Scopus: 147Incorporation of Partially Purified Hen Egg White Lysozyme Into Zein Films for Antimicrobial Food Packaging(Elsevier Ltd., 2006) Mecitoğlu, Çiğdem; Yemenicioğlu, Ahmet; Arslanoğlu, Alper; Elmacı, Zehra Seda; Korel, Figen; Çetin, Ali EmrahLysozyme, partially purified from hen egg white by precipitation of non-enzyme protein with ethanol and lyophilized after dialysis, was incorporated into zein films. The recovery and specific activity of the enzyme after partial purification varied between 45% and 72% and 2173 and 3448 U/mg, whereas the activity of the lyophilized enzyme varied between 2900 and 3351 U/mg. The partially purified enzyme was very stable and lost almost no activity in lyophilized form or in zein films stored at -18 and 4°C for up to 8 and 4 months, respectively. During partial purification and in zein film preparation, ethanol treatment caused 123-137% and 132-315% activation of the enzyme, respectively. In zein films incorporated with 187-1318 U/cm2 (63-455 μg/cm2) lysozyme, the release rates at 4°C, changed between 7 and 29 U/cm2/min, increased at high lysozyme concentrations. Zein films incorporated with partially purified lysozyme showed antimicrobial effect on Bacillus subtilis and Lactobacillus plantarum. By the addition of disodium EDTA, the films also became effective on Escherichia coli. The results of this study showed that the partially purified lysozyme may be used in antimicrobial packaging to increase food safety.Article Citation - WoS: 11Citation - Scopus: 16Partial Purification of Hen Egg White Lysozyme by Ethanol Precipitation Method and Determination of the Thermal Stability of Its Lyophilized Form(Türkiye Klinikleri Journal of Medical Sciences, 2007) Gemili, Seyhun; Umdu, Emin Selahattin; Yaprak, Nilgün; Üstok, Fatma Işık; Yener, Fatih Yalçın Güneş; Mecitoğlu Güçbilmez, Çiğdem; Altınkaya, Sacide; Yemenicioğlu, AhmetLysozyme was partially purified from hen egg white by precipitation of non-lysozyme protein impurities during incubation in the prence of ethanol. The thermal stability of the obtained partially purified enzyme was also characterized. The incubation of diluted egg white for 2-8 h in the presence of 20% ethanol was not very effective for the partial purification of lysozyme by precipitation of major egg white proteins; however, 4- to 6-h or 6-h to 8-h incubation of diluted egg white in the presence of 30% and 40% ethanol could be employed more effectively for partial purification of lysozyme. Without applying the incubation period, the highest specific activity was obtained by the treatment of egg white with 40% ethanol. Thus, ethanol at this concentration could be used for a continuous process of partial purification. For batch lysozyme purification, on the other hand, incubation in the presence of 30% ethanol was more appropriate. The activities and protein contents of dialyzed and lyophilized enzymes obtained by 6 h-incubation in the presence of 20%, 30%. and 40% ethanol precipitations were 1878, 6669, and 6115 U/mg powder, and 0.98, 0.90, and 0.93 mg protein per mg powder, respectively. The ranges of thermal inactivation parameters, such as D (D80°C = 29.2-59 min, D90°c = 8.8-21 min) and z (Z80-90°c = 17.4-22.3 °C) values of the enzyme, clearly indicated the moderate and variable heat stability of lyophilized lysozymes obtained from different batches of egg white.