In this study, a novel method using Ferula gummosa gums as a capping agent was used to synthesize the nanoceria for the first time. The method was economical and performed at room temperature. Furthermore, it was coated with gold (Au/nanoceria) and fully characterized using X-ray powder diffraction (XRD), field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM-EDX), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and zeta potential (ζ potential). The crystallite size obtained from the results was 28.09 nm for Au/nanoceria. The energy-dispersive X-ray spectroscopy (EDX) analysis of Au/nanoceria revealed the compositional constituents of the product, which display the purity of the Au/nanoceria. The cell toxicity properties of the non-doped and Au-coated nanoceria were identified by a MTT analysis on a breast cancer cell line (MCF7). Additionally, human foreskin fibroblast cells (HFF) were used as a normal cell line. The cytotoxicity results indicated that the toxicological effect of Au/nanoceria on cancer cells was significant while having little toxic effect on normal cells. The toxicity effect of nanoceria clearly shows the dependence on dose and time, so, with increasing the dose of Au/nanoceria, the death of cancer cells also increases.

Foeniculum vulgare (fennel) is a medicinal and aromatic plant species from Apiaceae (Umbelliferae) and has been extensively used to treat digestive and pulmonary diseases. This plant is relatively sensitive to salinity. To investigate the effect of salinity stress at levels of 0, 40, and 80 mM NaCl in combination with 0 and 5% v/v vermicompost mixed with soil on the growth as well as the physiological and biochemical traits of two fennel landraces planted in Urmia and Shiraz areas, a factorial experiment was conducted as a randomized complete block design in three replications under greenhouse conditions. The plants were sampled in the flowering stage eleven weeks after cultivation. As the results showed, vermicompost treatment together with salinity stress could enhance the growth traits of the plants, such as the length and dry weight of shoots; leaf area and dry weight of roots; photosynthetic pigments, i.e., chlorophylls and carotenoids; membrane stability index; relative water content, soluble sugar, soluble protein, proline, total phenol, and anthocyanin in the shoots; mineral elements, i.e., phosphate, nitrate, zinc, molybdenum, magnesium, and iron in the shoots; and potassium and calcium in the shoots and roots. The interaction of vermicompost and salinity also decreased the aldehydes, total flavonoids, activity of catalase enzyme and shoot starch, soluble sugar and root proline, and sodium content of both shoots and roots. In a comparison of the two studied fennel landraces, the Shiraz landrace emerged to be less affected by salinity stress. In saline conditions, vermicompost caused a change in the physiological and biochemical parameters of both fennel landraces and improved their growth. The improvement in the growth conditions in the Urmia landrace was more obvious due to the use of vermicompost. Using vermicompost plus 40 mM NaCl salinity, the dry weight of the shoot and leaf surface of the Urmia landrace increased by about 3 and 2.5 times, respectively, and under 80 mM NaCl, the dry weight of the shoot and leaf surface increased by 2.7 and 1.2 times compared to the control. According to the experiments, it seems that vermicompost can limit the harmful effects of salinity on fennel plants by affecting photosynthetic pigments, osmolytes, phenolic compounds, antioxidants, the stability of membranes, and the availability of water and essential minerals.