Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2026Scopus SJRQ1
    Microwave-assisted green synthesis of gold nanoparticles using MAE-derived aqueous Rubuscaesius L. Fruit extract: characterization and UV–Vis spectral stability

    Serdar, Gönül; Serdaroğlu, Vildan; Keşi̇r, Melek Koç; Kokoç, Memnune; Terzi̇oğlu, Salih

    Gold nanoparticles (AuNPs) were synthesized through a microwave-assisted green route using an MAE-derived aqueous Rubus caesius L. fruit extract as a natural reducing and stabilizing medium. The effects of precursor concentration, extract volume, and microwave power were systematically evaluated within the tested experimental range. The combination of 0.075 mM HAuCl₄0.3 H₂O, 0.4 mL fruit extract, and 180 W microwave irradiation produced the most distinct and symmetric surface plasmon resonance response. FT-IR analysis suggested that oxygen-containing functional groups in the extract may have contributed to Au³⁺ reduction and AuNP surface stabilization. TEM analysis revealed spherical, triangular, and hexagonal nanoparticles with an average core size of 11.6 ± 3.2 nm. DLS showed a hydrodynamic diameter of 71.92 ± 4.12 nm and a polydispersity index of 0.425, while the near-neutral zeta potential indicated limited colloidal stability. UV–Vis monitoring showed that the RC-AuNPs largely retained their spectral characteristics for up to 45 days. The synthesized nanoparticles exhibited a core size comparable to previously reported Rubus-mediated AuNPs. The specific contribution of this study is the use of an MAE-derived aqueous R. caesius L. fruit extract together with the systematic evaluation of key synthesis parameters affecting AuNP formation, optical response, and colloidal behavior.

  • MakaleYalnız künye2016Scopus SJRQ1
    Application of response surface methodology for optimizing the recovery of phenolic compounds from hazelnut skin using different extraction methods

    Odabaş, Halil İbrahim; Koca, Ilkay

    Hazelnut skin which is a rich source of phenolic compounds is a by-product of hazelnut roasting process. In present study, ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and supercritical carbon dioxide extraction (SCE) methods were applied for recovery of phenolic compounds from hazelnut skin. Response surface methodology was used to estimate optimum extraction conditions. Extraction studies were performed according to Box-Behnken Design. Temperature (UAE)/power (MAE), time and ethanol concentration were independent variables for UAE and MAE. The independent variables selected for SCE were temperature, time and pressure. The optimum extraction conditions were 45 min and 67.2–67.6% ethanol concentration, 600 W, 6 min and 55.03–56.23% ethanol concentration and 42.72–49.10 °C, 59.83–60.00 min and 10.01–11.48 bar, for UAE, MAE and SCE respectively. Total phenolic content, FRAP and 1/EC50 values at the optimum conditions were 122.99–123.01 mg GAE/g, 612.20–613.25 mmol Fe(II)/g and 4.36 mL/mg for UAE, 111.53–111.55 mg GAE/g, 582.44–582.52 mmol Fe(II)/g and 2.48 mL/mg for MAE and 69.59–72.64 mg GAE/g, 426.25–465.52 mmol Fe(II)/g and 2.18–2.27 mL/mg for SCE, respectively. Maceration was performed for comparison with novel methods. UAE was found to be the best method of the extraction of phenolic compounds from hazelnut skin with the highest total phenolic content and antioxidant activity values.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus89WoS78OpenAlex97
    ScopusWeb of Scienceİncele