Abstract: Corn germ was harvested during germination in a light or dark environment at different levels of temperature, and immersed in 0.05 mol/L phosphate buffer at pH 7.8 for different periods of time before SOD extraction and subsequent SOD activity measurement in order to explore the effects of germination and extraction conditions on SOD activity in corn germ. A maximum SOD specific activity of 4487.28 U/mg was obtained after the following operations: corn germination for 4 d under light illumination at 30 ℃, immersing of resulting corn germ in 200 mL of 0.05 mol/L phosphate buffer at pH 7.8 for 36 h, milling on a colloid miller, extraction for 1 h, thermal precipitation at 60 ℃ for 15 min, SOD precipitation from the supernatant by adding a 1.5-fold volume of －20 ℃ acetone, and sequential separation on cellulose-DE-52 and SephadexG-75 chromatographic columns, which exhibited a 3.86-fold increase in comparison with ungerminated corn germ (924.18 U/mg).

Key words: corn germ, germination condition, superoxidase dismutase(SOD), induction