Fecha de publicación: -- Fuente: PubMed "essential oil" Plant Physiol Biochem. 2026 Nov 7;240:111921. doi: 10.1016/j.plaphy.2026.111921. Online ahead of print.ABSTRACTThis study was designed to prepare bio-assisted Fe-based nanocomplexes (Fe-based NCs) using two different biological precursors, namely green tea extract (Fe-T NCs) and Kilka fish extract (Fe-F NCs), and to evaluate their physicochemical properties and effects on the foliar characteristics of Zataria multiflora Boiss. (Z. multiflora). The Fourier Transform Infrared (FTIR) spectroscopy showed that oxygen containing functional groups in green tea molecules and amide/carboxyl functional groups in Kilka molecules were responsible for Fe coordination and capping. The Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) observations indicated that Fe-T NCs exhibited a relatively more uniform morphology, whereas Fe-F NCs showed a more heterogeneous and aggregated structure. The biological assay indicated that 0.4% Fe-T NCs was the most effective foliar treatment, leading to marked improvements in vegetative growth, biomass production, chlorophyll accumulation, hydration status, membrane stability, and leaf structural traits. Oxidative stress was concurrently alleviated, evidenced by reduced hydrogen peroxide (H2O2) and malondialdehyde (MDA) accumulation and enhanced superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GPX) activities. The same treatment also maximized essential oil production and modified the oil profile, with thymol showing a notable increase. According to the principal component analysis (PCA) and correlation analyses, improved growth, water status, membrane integrity, antioxidant responses, and essential oil production were associated with lower oxidative stress markers. In summary, Fe-T NCs performed better than Fe-F NCs, possibly due to their polyphenol-associated surface chemistry, smaller particle size, and relatively improved colloidal behavior.PMID:43003037 | DOI:10.1016/j.plaphy.2026.111921