Changes of the antioxidant capacity in Gynura bicolor DC under different light sources

In this work, the effects of different light sources, including high pressure sodium lamp (HPS), T5 fluorescent lamps (T5) and Red-Blue light-emitting diodes (R-B LEDs), on the antioxidant capacity of Gynura bicolor DC were studied through the analysis on the changes of the antioxidant indicators (phenolic compounds, flavonoids, glutathione) and antioxidant activity (DPPH and FRAP) in G. bicolor. The results showed that the highest contents of phenolic compounds and flavonoids were found in G. bicolor under T5, and the antioxidant potential in G. bicolor evaluatedby either DPPH or FRAP assay also increased under T5 than others, while the antioxidant activity in G. bicolor under R-B LEDs with narrower spectrum was the lowest under the equal light intensity. (C) 2014 Elsevier B.V. All rights reserved.