Chinese ant extract preparations (CAEP) are a Chinese traditional medicine which is mainly used as a health food or drink for the treatment of rheumatism, rheumatoid arthritis, chronic hepatitis, rheumatoid arthritis, and antiaging in China. The effects on free radicals were examined by electron spin resonance spectrometry using the spin trapping agent 5.5-dimethyl-1-pyrroline-1-oxide (DMPO). Superoxide radicals (3.35 x 10(15) spins/ml) were quenched 50% by the extract at 0.5 mg/ml. The CAEP extract at 0.7 mg/ml inhibited 50% of hydroxyl radicals (52.0 x 10(15) spins/ml) generated by the Fenton reaction.
