EFFECT OF LONG-TERM FEEDING OF RICE BRAN OIL UPON LIPIDS AND LIPOPROTEINS IN RATS

The effects of feeding two levels of rice bran oil (RBO) on the growth , lipid parameters, and fatty acid composition of the plasma and liver of rats (Wistar strain) were compared with those produced on animals which had been fed the same levels of peanut oil (PNO). The control an imals were fed synthetic diets containing 5 and 20% peanut oil (PNO) a nd the experimental groups were fed similar diets, containing the same level of rice bran oil (RBO). There was no significant difference wit h respect to the organ weights between the control and the experimenta l groups. In general, groups fed 20% oil gained more weight than group s fed 5% oil. The animals which received rice bran oil in their diet h ad, in general, comparatively lower levels of cholesterol, triglycerid es and phospholipids. On the other hand, animals receiving 20% rice br an oil in their diet, showed an increase of 20% in high density lipopr oteins (HDL-C), within 18 weeks (p < 0.05), when compared to the anima ls fed with peanut oil. Similarly low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) were low er in RBO-fed groups, than in the PNO-fed groups. There was, however, no significant differences in the cholesterol/phospholipid (C/P) ratio of the two groups. Analysis of plasma and of liver fatty acids indica ted, in a general way, the type of fat consumed. There were no signifi cant difference in the P/S ratio, nor any in the oleic/linoleic, oleic /stearic, palmitoleic/palmitic, oleic/palmitic, and oleic/palmitoleic ratios. Furthermore, levels of saturated (SAFA), monounsaturated (MUFA ), and polyunsaturated (PUFA) fatty acids were identical in both the g roups. Thus, our results suggest that feeding a high level of rice bra n oil (RBO) has no deleterious effect on the growth and blood lipid pr ofile of rats.