Effects of cadmium on total phenolic compounds and flavonoids in Euglena gracilis
In the present study the production of phenolic acids and flavonoid compounds by E. gracilis exposed to two cadmium concentrations (0.02 and 0.14 mM) was evaluated using high-performance liquid chromatography (HPLC). The results showed that E. gracilis exposed to 0.02 mM Cd+2 increased significantly the total content of phenolic compounds (798.46 ± 12.61 μg GA/g) and total flavonoids (241.34 ± 47.63 μg QE/g) with respect to the control (137.34 ± 19.80 μg QE/g DW and 549.00 ± 8.57 μg GA/g DW, respectively). However, no significant increase in the total content of phenolic compounds (568.54 ± 17.42 μg GA/g DW) and total flavonoids (141.11 ± 9.36 μg QE/g DW) were observed in E. gracilis exposed to 0.14 mM Cd+2. Further research is necessary to determine the specific role of flavonoids in E. gracilis exposed to high concentrations of Cd+2.