Carum carvi mediated green synthesis of copper nanoparticles and its effect on Solanum lycopersicum seedlings

The present study aims to synthesis the copper nanoparticles (CuNPs) and their effect on the biochemical and physiological characteristics of Solanum lycopersicum. The results exhibited the color change in the Carum carvi aqueous extract from clear deep brown to a greenish color and this observation indicated the green-biosynthesis of CuNPs by reduction of Cu+ to Cu0. Also, the absorbance broadening band for the green-biosynthetic CuNPs appeared at the 340 nm wavelength using UV-Vis but the C. carvi aqueous extract not showed any peaks at this wavelength. SEM analysis exhibited the micrographic surface morphology and the shape of the green-biosynthetic CuNPs with a scan area of 50 μm and showed the spherical shape particles of CuNPs aggregation. The three-dimensional image and the surface morphology of green-biosynthesized CuNPs and C. carvi aqueous extract were examined using AFM analysis that showed the surface of C. carvi aqueous extract was 45.5 nm size with non-homologus and irregular form of distribution, but the green-biosynthesized CuNPs were 12.4 nm size in nanoscale with regular and homogenous distribution form. The results also showed that the effect of bio-synthesized copper nanoparticles was evident on the S. lycopersicum seedlings fresh and dry weight according to the different reading times after treatment with nanoparticles. Also, the concentration of 2.5 mg/mL (CuNPs) showed a significant increase in the chlorophyll content (58.51 μg/cm²) on the 21st day after treatment and a significant increase in the activity of peroxidase enzyme (35.12 U min-1 mg-1 protein) was obtained at the concentration of 2.5 mg/mL (CuNPs) at 21st day after germination.