Influence of fruit and vegetable extracts on lipid peroxidation in microsomes containing specific cytochrome P450s

We have examined the effect of 12 food extracts on iron/ascorbate-induced lipid peroxidation using microsomes enriched with specific cytochrome P450 isoenzymes, namely 1A1 and 3A4, prepared from human lymphoblastic cells. As a comparison, we also studied control microsomes, which contained negligible amounts of cytochrome P450. We observed antioxidant effects with both control and P450-containing microsomes in the case of grapefruit, green tea, coffee, tarragon and rosemary extracts. Pro-oxidant effects were observed for the brassica extracts (cabbage, cauliflower and Brussels sprouts) for all three microsome groups. Differences in the degree of lipid peroxidation between microsomes containing P450s 1A1/3A4 and control microsomes were seen for apple, tomato and parsnip peel extracts. The antioxidant properties of some of the food extracts were therefore modified by the presence of specific P450s. The results demonstrate the potential of P450-enriched microsomes in determining the antioxidant properties of food extracts and components.