Biosynthesis of NanoSilver and Its Effect on Key Genes of Flavonoids and Physicochemical Properties of Viola tricolor L.

Abstract

Wild pansy (Viola tricolor L.) is of the Violaceae plant family. Some of the medicinal properties of this plant are related to the ability to produce and biosynthesized a group of flavonoids. Silver nanoparticles are one of the most important and attractive nanomaterials among several metal nanoparticles.In the present study, plant-mediated nanosilver was produced from aqueous extract of Pansy flower as a good covering and stabilizing agent using the green synthesis method. Dynamic light scattering (DLS), transmission electron microscopy (TEM), and zeta potential methods were used to determine the specifications of synthesized nanoparticles. In this study, the effect of different concentrations of bio nanosilver 0, 10, 50, and 100 mg/l on phytochemical and physiological properties, and the expression of some key genes involved in flavonoids biosynthesis including phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), flavonoid 3′, 5′-hydroxylase (F3′5′H), and flavonoid 3′-hydroxylase (F3′H) were determined in V. tricolor plant. The results showed nanosilver treatments cause the accumulation of manganese, zinc, and silver elements and increasing the content of phenolic, flavonoid, anthocyanin and antioxidant activity. Using AgNPs also causes the increase in activity of antioxidant enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX), phenylalanine ammonia-lyase (PAL), and peroxidase (POD). Besides, treatment with a concentration of 10 mg/l of silver nanoparticles significantly causes an increase in flavonoids compounds such as rutin, apigenin, and quercetin. Our results suggest that bio nanosilver could increase secondary metabolites content in the V. tricolor plant.