Achievement of Iranian researchers
potential of titanium dioxide(TiO2) nanoparticles to counteract the adverse effects of UV-B radiation in saffron plant
A new study has shown that titanium dioxide(TiO2) nanoparticles have the potential to counteract the adverse effects of UV-B radiation in saffron plant.
Altered properties of saffron plants exposed to TiO2 nanoparticles and Ultraviolet-B stress
Saffron (Crocus sativus L.) is considered as one of the most commonly known medicinal and aromatic plants in the world. A new study has shown that titanium dioxide(TiO2) nanoparticles have the potential to counteract the adverse effects of UV-B radiation in saffron plant.
In recent decades industrial activities have increased the concentration of air pollutants in the atmosphere. Some of these pollutants are compounds that contain stable halogens with the ability to damage ozone layer. With the destruction of ozone layer, UV radiations could reach the earth and become a challenge for living organisms.
The effects of UV-B on plants are inevitable since plants are in constant need of solar radiation. Uv radiation impairs photosynthesis, degrades proteins and nucleic acids, causes oxidative stress and destroys photosynthetic pigments. Moreover, UV radiation creates free radicals which impair metabolic equilibrium inside the cells.
The primary adaptation mechanism that plants use against UV radiation is to increase the width of their leaves and the amount of molecules such as flavonoids and anthocyanin to absorb UV-B. Additionally, plant cells also have an anti-oxidative defense system which could neutralize devastating effects of reactive oxygen species. This system includes both enzymatic and non-enzymatic processes.
Nanoparticles can move into the cells by crossing the pores on the surface of the leaves. Nanoparticles can produce a wide range of physiological and morphological changes within the cells, based on their properties. Titanium dioxide nanoparticles (TiO2 NPs) have all the properties of TiO2. But because of their smaller size, they have an expanded contact surface and thus, an improved function. The current study was performed to investigate the reaction of TiO2 treated saffron plants to destructive UV-B exposure. Also, chemical properties and also the antioxidant activity of saffron’s stigma and leaves were investigated in order to elucidate the effect of TiO2 nanoparticles.
According to the results, loss of mass, decrease in elongation and the loss of dissolved sugars were among the adverse effects of UV-B. As expected, the amount of flavonoids, anthocyanin and phenols increased in response to UV radiation in plants that were treated with TiO2 NPs.
Based on the fact that UV-B radiation significantly altered the amount of antioxidant molecules inside the stigma of plants exposed to TiO2 NPs, it could be concluded that these nanoparticles have the potential to decrease the adverse side effects of UV-B radiation. Furthermore, TiO2 NPs could also be used as a mean to increase the amount of antioxidant and thus the nutritional value of saffron.