PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
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Article Analytical Methodology for Monitoring and Distribution Pattern Analysis of Polycyclic Aromatic Hydrocarbons in River Basins Based on Chemometrics(Wiley, 2025) Yildirim, Ebru calkan; Pelit, Fusun; Ozdemir, Durmus; Kazan, Aysegul; Tasdelen, Ozge; Baycan, NevalWith the increase in urbanization and industrialization, the environmental quality of river basins, which serve as a crucial source of irrigation for agricultural activities, has been deteriorating progressively. Thus, monitoring persistent toxic substances in urban water resources is crucial for maintaining ecological stability and protecting human health. In recent years, particular attention has been directed toward the prevention of polyaromatic hydrocarbons (PAHs), highlighting the importance of analyzing these compounds in water samples through more environmentally sustainable techniques. In this study, we report a green, rapid, cost-effective and simple dispersive liquid-liquid extraction (DLLME) method to monitor PAHs in river waters taken from 21 stations located within the geographical boundaries of the Gediz River Basin in Izmir Province, T & uuml;rkiye. Methodological parameters were optimized by chemometric techniques including Plackett-Burman (PBD) and Box-Behnken design. The method's accuracy was tested upon spiked river samples, and the recoveries ranged from 80% to 102%. The calibration curves were linear, with correlation coefficients greater than 0.98. The limit of detection values were between 0.01 and 0.05 ng mL-1. The reproducibility (RSD%) varied from 4.0% to 19%. Multivariate classification methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA), along with the supervised classification method partial least squares discriminant analysis (PLS-DA) were applied to elucidate the general distribution patterns of individual PAHs in the basin water samples. The chemometric evaluation conducted across four seasons revealed that PAH contamination was higher in the fall and winter months, resulting in a clear separation from spring and summer samples by using the first two principal components.Article Influence of Soil Characteristics on the Phytochemistry of Evergreen Ivy (Hedera Helix L.) Leaves in Deciduous Forests(Wiley-v C H verlag Gmbh, 2025) Yildirim, Elif Begum; Ozer, Gulcin; Sen, Nisa Beril; Ozdemir, Emrah; Makineci, Ender; Ozdemir, Durmus; Guzelmeric, EtilThe evergreen ivy (Hedera helix L.), traditionally used to treat respiratory conditions, contains triterpene saponins, primarily hederacoside C, and various phenolic compounds. This study investigated the relationships between the chemical composition of ivy leaves and their natural growing conditions (moisture, temperature, pH, and electrical conductivity of soil). Ivy leaves were collected monthly over 1 year from oak and beech forests. Hederacoside C, rutin, chlorogenic acid (ChA), neoChA, 4,5-dicaffeoylquinic acid (DCQA), and 3,5-DCQA were analyzed by high-performance thin-layer chromatography (HPTLC) and high-performance liquid chromatography (HPLC). Soil parameter data, along with the quantitative HPLC results of ivy leaves, were first subjected to bivariate analysis, which revealed significant correlations, particularly between soil moisture, soil temperature, and the chemical composition of ivy leaves. In addition, ivy samples were classified and clustered based on seasons by principal component analysis (PCA) and hierarchical cluster analysis (HCA), regardless of their collection sites. Digitized HPTLC chromatograms were evaluated by PCA and partial least squares discriminant analysis (PLS-DA) analyses; PCA enabled the grouping of ivy leaves based on their collection sites, and PLS-DA categorized the samples by seasons. The evaluation of the relationships between the phytochemistry of ivy leaves and their natural growing conditions has been reported for the first time.
