Normal rats were killed and livers excised, rapidly
washed and homogenized with 8 vol (w/v) of 5 mM Tris–
HCl buffer (pH 7.4) containing 0.25 M sucrose and
0.1 mM EDTA. Sub cellular fractionation was carried
out using differential centrifugation and pelleted microsomes
were diluted with the same buffer. Reaction mixture
contained 50 ll of PF (diluted in 60% methanol) from test
oils, 10 ll microsomes, 500 ll Tris–HCl buffer (pH 7.4)
containing 12.5 lM FeSO4 Æ 7H2O and 40 ll 2 mM ascorbic
acid. The reaction mixture was incubated at 37 C for
30 min followed by centrifugation. 0.3 ml of TBA was
added and kept in a boiling water bath for 5 min. Absorbance
was measured at 530 nm. a-Tocopherol was used
as positive standard. The result was expressed as percentage
inhibition compared to control (Kweon, Hwang, &
Sung, 2001).