Two grams of fruit tissues were homogenized in 10 mL of
100 mmol L1 sodium phosphate buffer (pH 7.8) containing 5%
polyvinylpyrrolidone and 5 mmol L11,4-dithiothreitol at 4 C. The
homogenate was centrifuged at 10,000
g for 15 min at 4 C, and
then the supernatant was collected for SOD activity assay as
described by