HEMATO-BIOCHEMICAL PARAMETERS IN RATS FED LUPINUS-ANGUSTIFOLIUS L (SWEET LUPIN) SEED PROTEIN AND FIBER FRACTIONS

The effects of Lupinus angustifolius L. (sweet lupin), cv. Unicrop see d meal and five of its fractions on different parameters of blood, pla sma/serum and liver were studied in two experiments. Groups of four gr owing rats were pair-fed for 10 days on diets that contained the same amounts of energy and protein and were supplemented with amino acids a nd minerals to target requirements for growing rats. In addition to th e lactalbumin (LACT) and raw lupin seed meal, which was fully suppleme nted (LMFS), five fractions were tested: four protein fractions (aqueo us fractions that were soluble [LPAD] and insoluble [LPADI] after dial ysis at pH 7.0, and phosphate-citrate buffer extracted ones that were soluble [BUSOL] and insoluble [BUDI] after dialysis at pH 7.0) and dia lyzed residue (LMR) containing the material from the meal insoluble in water and buffer. The cellular components and parameters of blood pla sma and serum were subjected to detailed studies. Cellular elements we re, in fact, little affected by the seed meal and its fractions when c ompared with those obtained from the control. Significant changes, how ever, were found in plasma urea (p<0.05), albumin (p< 0.05), alkaline phosphatase (p<0.05), total cholesterol (p<0.01), triglycerides, and l iver lipid and cholesterol. A significant lowering effect on total pla sma cholesterol was observed in growing rats fed the seed meal and its fractions compared with that value obtained from the lactalbumin cont rol. The buffer-dialyzed insoluble (BUDI) fraction, which resembled ga mma-conglutin and was found to be in an almost pure form, lowered tota l plasma cholesterol by 34% compared with that value for the lactalbum in fed group. Liver lipid and cholesterol were also found to be decrea sed in rats fed L. angustifolius seed meal and its fractions. The obse rved hypocholesterolemic effects were greater than any values previous ly reported for such a short feeding period. The underlying mechanism( s) of the cholesterol lowering effects is not clear. However, the disp roportionate value for arginine : lysine and/or cystine : methionine i n the proteins may be a modulating factor(s). In addition, other bioch emical changes were dependent on the involvement of general N metaboli sm and/or parenchymatous degeneration of the liver tissues by some unk nown modulating factor.