After rye (Secale Ceerale) tissue, labelled with C14, had been incubated with a peat soil, the soil was extracted with various solvents. One fractionation procedure was the proximate analysis method according to Waksman and Stevens (15). The other procedure was a comparison of the components extracted by 0.1m Na4P2O7, 0.5n NaOH, and 6n HCl.
In the proximate analysis, the distribution of total carbon in benzene-methano (10:1), 2% HCl, 80% H2SO4, and insoluble portion was 1.9, 30.8, 17.2, and 50.1%, respectively. The respective distribution of C-14 was 40.3, 20.5, 13.4, and 25.8%. The fraction containing the smallest proportion of carbon had the largest proportion of C-14.
The 6N HCl extract was separated into more discrete fractions by gel infiltration than the extracts of 0.1M Na4P2O7 and 0.5n NaOH. However, the NaOH removed a greater proportion of the radioactive materials.