Protective Role of a methanolic Extract of Spinach (Spinacia oleracea L.) Against Adverse Effects of UV-C Irradiation on Fenugreek (Trigonella foenum-graecum L.) Seedlings

Abstract

Photosynthesis is an important process for plants in which plants utilize the energy from sunlight to manufacture and produce all their own food. Although UV-C damage is not physiologically relevant for plants growing in the sun, short-wavelength (UV-C) radiation from germicidal lamps has been used to study cell damage in animals as well as in plants. This study provides a review of the effects of a methanolic extract of spinach (SE) as a natural powerful antioxidants used at two concentrations (25 and 50 ppm) on fenugreek seedlings grown under UV-C stress conditions. The results revealed that exposure of fenugreek seedlings to low UV-C period (30 min) increased growth criteria of the produced seedlings. In addition, the contents of chlorophyll, total pigments, total protein, free amino acids, nonenzymatic (carotenoids, total phenol, flavonoids, α-tocopherol & ascorbic acid contents) and enzymatic antioxidants were increased at this period. By increasing exposure periods of UV-C radiation, the growth criteria and chemical constitutes of the seedlings were decreased. Application of lower concentration of SE (25 ppm) improve the growth of the seedlings at 30-min UV-C and was able to protect seedlings from high periods of UV-C irradiation by increasing all measured parameters except CAT. These increases might be an adaptive mechanism to minimize the adverse effects of longer exposure of UV-C radiation. Moreover, treating the irradiated seedlings with spinach extract led to an obvious alteration in gene expression including synthesisof some proteins bands and disappearance of other protein sets of the protein profile.