Abstract
It is necessary to develop a simple way to achieve food quality quantitatively. Nanotechnology is a key advanced technology enabling contribution, development, and sustainable impact on food, medicine, and agriculture. In terms of medicinal and therapeutic properties, Hypericum perforatum is an important species. For this study, a randomized complete block design with three replications was used in each experimental unit. The foliar application of selenite and nano-selenium (6, 8, 10, and 12 mg/l), control (distilled water), at the rosette stage and harvesting at 50% flowering stage has been applied as an alleviation strategy subjected to producing essential oils and antioxidant activity. Experimental results revealed that the selenite and nano selenium fertilizers had a significant effect on traits such as total weight of biomass, essential oil percentage, the content of hypericin and hyperforin, the selenium accumulation in the plant, relative leaf water content, chlorophylls, phenolic content, proline, catalase, peroxidase, malondialdehyde, and DPPH. The highest essential oil content was obtained from the control treatment when the accumulation of selenium was achieved with 12 mg/l nano-selenium. The maximum rate of hypericin was seen in the foliar application of 8 mg/l selenite whereas the maximum hyperforin was gained at 10 mg/l selenium. Conceding that the goal is to produce high hypericin/ hyperforin, and also the accumulation of selenium in the plant, treatments of 6 and 8 mg/l of selenite and nano-selenium could be applied. Consequently, an easy detection technique proposed herein can be successfully used in different ranges, including biology, medicine, and the food industry.