Green synthesis of silver nanoparticles using Cedrela odorata and their fungicidal activity against Fusarium circinatum.

This study reports the green synthesis and characterization of silver nanoparticles (AgNPs) assisted with Cedrela odorata extracts and their antifungal efficacy against Fusarium circinatum, one of the most threatening pathogens in forest nurseries. Various extract volumes (1, 3, and 5 mL) of leaf and the bark of red cedar were tested. The nanoparticles were characterized using UV-Vis spectroscopy, transmission electron microscopy, and energy-dispersive spectroscopy of X-rays (EDS-TEM). Phytochemicals in the extracts were explored using Fourier transform infrared spectroscopy (FTIR). The results were analyzed using ANOVA and Tukey's tests with (p ≤ 0.05, 95%). Both leaves and bark extracts produced AgNPs, but the particles from bark extract (AgNPs-B) were smaller (19.80 ± 9.88 nm, λmax at 447 nm), and they were more stable than particles from leaf extract (AgNPs-L) because they showed a superficial plasmon resonance (SPR) over 12 months. Phenols and triterpenoids, associated with -OH, C=O, and –NH, were identified in the plant extracts that could act as reducing and capping agents. The AgNPs exhibited good antifungal activity because the inhibition diameter (11.38 ± 0.8 mm) observed for 800 mg AgNO3 L−1 was statistically similar to the inhibition diameter (10.7 ± 0.7 mm) at lower concentrations of particles (200 mg AgNPs L−1), and benzimidazole showed no fungus inhibition. Hence, it could be concluded that the bark extract performed better than the leaf extract. In conclusion, this study reports a new method for the synthesis of AgNPs assisted with cedar bark that exhibit a good antifungal activity against F. circinatum. [ABSTRACT FROM AUTHOR]