Distribution and activity of superoxide dismutase, catalase, peroxidase and xanthine oxidase were investigated in human amnion. Human amnion was fractionated by differential centrifugation into mitochondria) and cytosolic fraction. Cytosolic superoxide dismutase was purified by ammonium sulfate precipitation, treatment with ethanol-chloroform mixture, and DEAE-cellulose column chromatography.
The results were summarized as follows;
1. The activity of superoxide dismutase in homogenate was found to be 20.4 units/g of wet tissue. The distribution of superoxide dismutase in the subcellular organelle showed that 94.67o of the activity was in cytosolic fraction and 5.4% in mitochondria) fraction.
2. The cytosolic superoxide dismutase was purified approximately 22 fold. Cyanide at O.5mM and 5.OmM inhibited the activity of cytosolic superoxide dismutase 15.2% and 82.1%, respectively. But the´activity of mitochondrial superoxide dismutase was inhibited about 24.4% by 1mM and 5mM cyanide.
3. The activity of catalase in homogenate was found to be 607.5 units/ml enzyme and the relative activity of cytosolic and mitochondrial catalase was 86.47o and 13.67c, respectively.
4. The activity of peroxidase in homogenate was found to be 157.4 units/ml enzyme and the relative activity of cytosolic and mitochondrial peroxidase was 83.8 % and 16.2 %, respectively.
5. The activity of xanthine oxidase in homogenate was found to be 3.5 units/ml enzyme and the relative activity of cytosolic and mitochondrial xanthine oxidase was 66.1 To and 33.9%, respectively.
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