Improvement of bioactive compounds by exogenous sucrose absorbed via mugwort and kale roots

Abstract

In plants, sucrose (suc) acts as a signaling molecule for various plant metabolism processes and is one of the translocation forms of carbohydrates. This study aimed to determine the effect of exogenous suc on the accumulation of antioxidative phenolics in mugwort (Artemisia princeps) and kale (Brassica oleracea var. acephala) plants and to evaluate the protective effect of mugwort extract treated with suc on ethanol-induced cell damage. Two-week-cultured mugwort plants and threeweek- cultured kale plants were subjected to Hoagland nutrient solution containing 10, 30, and 50 mM suc for 4 and 3 days. As a result, the shoot fresh weights in the suc treatments were not significantly different from the control in both plants. However, the sugar content in kale leaves in all treatments was significantly higher than the control at 3 days of treatment. The total phenolic content and antioxidant capacity of mugwort increased as suc concentration increased. For kale, the suc 30 mM treatment had significantly higher antioxidant capacity than the control at 1 and 3 days of treatment. However, the other suc concentrations did not affect the change of antioxidant capacity. Total phenolic content in the kale plants was not significantly affected by the exogenous suc addition. The protective effects of the extracts from the suc-treated mugwort were examined by MTT assay against ethanol-induced cell damage. Ethanol-induced cell damage was observed in the ethanol treatment; however, pretreatment of the extract significantly reduced the ethanol-induced cytotoxicity. Therefore, the kale and mugwort plants could absorb exogenous suc via roots, and suc might stimulate the biosynthesis of antioxidant phenolic compounds or certain bioactive compounds, efficiently protecting hepatocytes against ethanol-induced cell damage in mugwort.