Subcellular distributions of copper and lead in Herba Plantaginis

We studied the subcellular distributions of Cu and Pb in leaves of Herba Plantagini taken from sites at Baobeidang(BBD) and Luxian(LX) in Sichuan Province. The results indicate that the biomass and the content of Cu and Pb were higher in H. Plantagini from BBD than that from LX. The levels of Cu and Pb in H. Plantagini from BBD were highest in the cytoplasmic organelles,less in the cell wall and lowest in the cytoplasmic supernatant. The levels of Cu and Pb in H. Plantagini from LX were highest in the cell wall,less in the cytoplasmic organelles and lowest in the cytoplasmic supernatant. The level of Pb was higher than that of Cu in all subcellular fractions. Cytoplasmic organelles include the important sites involved in photosynthesis and respiration and have the capacity to absorb Cu and Pb. The cell wall can form very strong bonds with Cu and Pb. These findings may explain why H. Plantagini is capable of detoxification.