Modulation of Lipid Peroxidation by Dietary Components

The aqueous extracts of commonly consumed Indian spices and vegetables were tested for their
antioxidant properties in human erythrocyte membranes against lipid peroxidation induced by
FeSO,-ascorbate (10: 100 pmol/system). Aqueous extracts of curry leaves (Murraya koneigii) at 10 pg/ml
and of asafoetida (Ferula spp), omam (Curum ajowun) and mustard (Brarsica nigru) at 300 pg/ml inhibited
lipid peroxidation by 90, 85, 75 and 70%, respectively. The aqueous extracts of cabbage (Erassicu
oleruceu), ginger (Zinziber oficinule) and onion (Allium cepu) inhibited lipid peroxidation by 65, 72 and
66%, respectively. The aqueous extracts of spices were also found to inhibit the formation of diene, triene
and tetraene conjugates in human erythrocyte membrane. Addition of lipid peroxides extracted from
peroxidized human erythrocyte membrane substantially increased erythrocyte lysis over that caused by
exposure to 0.54% saline alone. Aqueous extracts of omam, coriander seeds (Coriandrum sutivum) and
curry leaves, at 300 pg/ml, inhibited peroxidized lipid-induced lysis by 67, 72 and 87%, respectively. Lipid
peroxides induced considerable activation of polymorphonuclear leucocytes activation and this activation
was inhibited by the aqueous extract of curry leaves.