In vitro germination and biochemical profiling of Brassica napus in response to biosynthesised zinc nanoparticles.

With the progression of nanotechnology, the use of nanoparticles (NPs) in consumer products has increased dramatically and green synthesis is one of the cheapest and eco-friendly methods to obtain non-hazardous NPs. In the current research zinc (Zn) NPs synthesis was carried out by using the fresh and healthy leaves of Mentha arvensis L. followed by characterisation through ultraviolet (UV)-visible spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). UV-visible spectroscopy confirmed the green synthesis of ZnNPs, while XRD confirmed the size of NPs, which was 30-70 nm. SEM shows that the shape of ZnNPs was irregular. The effects of green synthesised NPs on two different varieties of Brassica napus were evaluated. Exposure to ZnNPs (5, 15, and 25 mg/l-1) caused a significant increase in root and shoot length of B. napus. The application of NPs significantly improved plant germination and triggered the production of secondary metabolite and antioxidant enzymes. ZnNPs showed a significant increase in chlorophyll, superoxide dismutase, total flavonoid content (TFC) and antioxidant enzymes while total phenolic content was decreased when TFC increased. Thus, it has been concluded from the current study that ZnNPs may possibly trigger the production of antioxidant enzymes and various biochemical compounds.