Changes in Phenol compounds content due to Changes in Light Intensity in Thymus vulgaris L.

Thymus vulgaris L. belongs to the Lamiaceae family. The chemical composition of T.vulgaris includes phenols and terpenoids, especially thymol, eugenol and saponins (۱). Phenols and phenolic compounds such as flavonoids act as antioxidants and eliminate the cytotoxic effects of oxygen free radicals in the plants. The large amount of phenols and flavonoids in the plant extract can explain that high antioxidant activity in the plant (۲).In this Study, the plant cuttings were grown in greenhouse conditions for ۶ months. Then they were taken out of the greenhouse and treated with different light intensities in a randomized complete block design (CRD) with three replications. To apply different light intensities, green shades with different shading percentages were used. The percentage of natural light that the plant provides is as follows: ۲۰%, ۵۰%, ۷۰% and ۱۰۰%. After two months of treatment, the phenolic content of the samples was determined using Folin-Ciocalteu reagent method and Gallic acid as the standard (۲). Data analysis was performed with SAS ۹.۰ software and finally the graphs were drawn in Excel ۲۰۱۶ software. The results of statistical analysis showed that there is a significant difference between all four light levels in terms of the amount of phenol production. The amount of phenol production in ۲۰, ۵۰, ۷۰ and ۱۰۰% light treatments is ۲.۰۶, ۱.۶۹, ۱.۹۲ and ۲.۳۳ (ng / ml), respectively. These changes do not follow a linear pattern. In fact, with decreasing light intensity, the production of phenol first decreases and then increases. On the results, it can be said that more free radicals are produced against light, and as a result the need for phenols, which are plant antioxidants, increases.

کلیدواژه ها:

Thymus vulgaris ، Antioxidants ، light filters