Speciation of low molecular weight aluminium complexes in roots of tea plant (Camellia sinensis L.)

摘要

To identify the chemical forms of aluminum (Al) in roots of tea plants {Camellia sinensis L.), excised root tips (0-5 mm and 5-20mm) and free space solution (FS) and cell saps (CS) extracted from each part of root tips were analyzed by ~(27)Al-nuclear magnetic resonance (NMR). Aluminum-27-NMR spectra of both parts of excised roots and their CS were very similar, showing four signal peaks, at around 0, 3, 10, and 16 ppm. In FS, little signal was detected in the 5-20 mm part, although there were two very small and broadening signals at around 0 an d 11 ppm in the 0-5 mm part. These results suggest the presence of Al-oxalate and/or Al-citrate complexes in tea plant roots.