Electron spin resonances of a living system (Drosophila) on normal and carcinogenic diets

This investigation was a study of the free radical concentration of a living system, Drosophila melanogaster, by electron spin resonance spectroscopy. The paramagnetic content of the organism was measured as a function of age, mutant strain, and diet (normal vs. carcinogenic). In all cases, 4 to 6 days after ecdysis the free radical concentration decreased to approximately 70% of its value as measured shortly after ecdysis. The different mutant strains exhibited distinctly different free radical concentrations in accord with visual observations of the degree of pigmentation. Drosophila raised on a carcinogenic diet always showed a lower concentration of free radicals than the control groups on a normal diet.