Effect of cadmium on phenolic compounds, antioxidant enzyme activity and oxidative stress in blueberry (Vaccinium corymbosum L.) plantlets grown in vitro

Cadmium (Cd2+) can affect plant growth due to its mobility and toxicity. We evaluated the effects of Cd2+ on the production of phenolic compounds and antioxidant response of Vaccinium anymbosum L Plantlets were exposed to Cd2+ at 50 and 100 mu M for 7, 14 and 21 days. Accumulation of malondialdehyde (MDA), hydrogen peroxide (H2O2) and the antioxidant enzyme SOD was determined. The profile of phenolic compounds was evaluated using LC-MS. The antioxidant activity was measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the ferric reducing antioxidant power test (FRAP). Cd2+ increased the content of MDA, with the highest increase at 14 days. The presence of Cd2+ resulted in changes in phenolic compounds. The main phenolic compound found in blueberry plantlets was chlorogenic acid, whose abundance increased with the addition of Cd2+ to the medium. The changes in the composition of phenolic compounds showed a positive correlation with the antioxidant activity measured using FRAP. Our results suggest that blueberry plantlets produced phenolic compounds with reducing capacity as a selective mechanism triggered by the highest activity of Cd2+. (C) 2016 Elsevier Inc. All rights reserved.