Chemical state analysis of sulfur and phosphorus in biological samples by X-ray fluorescence

Double-crystal high-resolution X-ray fluorescence spectroscopy was applied to the chemical state analysis of sulfur and phosphorus in biological samples of leaves and bones. Both S(2-) and S(6+) states are present in all leaves. In plants infected with the mosaic virus, the abundance of S(2-) state was found to be less than normal.Furthermore, the total sulfur content of leaves with the mosaic virus was less than that in normal leaves. From these results we have concluded that the mosaic virus is related to the decrease in cysteine sulfur (S(2-)), which is an essential component in amino acids. Most of the phosphorus in leaves and bones was found to be in P(5+) state. A small amount of P(3+) state, however, was also detected.