Effects of untreated and thermally treated lupin protein on plasma and liver lipids of rats fed a hypercholesterolemic high fat or high carbohydrate diet.

摘要

Lupin protein is capable of reducing plasma lipids in hypercholesterolemic man and animals. Whether lipid-lowering properties of lupin protein will be influenced by thermal treatment or by other nutrients has not been elucidated. In a two-factorial study, rats were fed hypercholesterolemic diets based on high amounts of carbohydrates (HC) or fat (HF), which contained either (20.4% of energy) untreated or thermally treated lupin protein (steam: 120 degrees C, 30 min) or casein as control protein. Lupin protein lowered plasma lipid concentrations in rats fed the HF diet but not in those fed the HC diet (P < 0.05). Among rats fed the HF diet, plasma and VLDL triglyceride concentrations were lower in rats fed thermally treated (--46% and --44%, P < 0.05) and untreated lupin protein (--47% and --46%, P < 0.05) than in those fed casein; whereas liver triglycerides were reduced only in rats fed untreated lupin protein (P < 0.05). Compared to casein, untreated lupin protein had slightly stronger cholesterol-lowering effects in plasma, LDL and HDL (--34%, --37%, --35%; P < 0.05) than thermally treated lupin protein (--23%, --29%, --31%, P < 0.10). In conclusion, the lipid-lowering effect of lupin protein strongly depends on composition of the basal diet, and thermal treatment is accompanied by a slight reduction of its hypocholesterolemic properties.