The hypocholesterolemic action of the undigested fraction of soybean protein in rats

Soybean protein fraction digested with neutral protease preparation, “Peptidase R”, produced by Rhizopus oryzae, stimulates innate cellular immune system in mouse

“…Additionally, soybeans have recently been demonstrated to possess a variety of physiological functions including anti-hypercholesterolemic and antitumor activities [1][2][3]. Some of these functions have been reported to be due to soybean proteins and their digests.…”

Effects of Dietary Soybean Peptides on Hepatic Production of Ketone Bodies and Secretion of Triglyceride by Perfused Rat Liver

“…Sugano et al has shown that undigested high-molecular-weight peptides might effectively bind bile acids in the intestine and thereby increase fecal excretion of both neutral and acidic steroids, resulting in induction of the hypocholesterolemic effect. [7][8][9][10] Thus, high-molecular fraction in soybean peptides can modulate cholesterol metabolism through the stimulation of fecal steroid excretion.…”

“…[1][2][3][4] The hypocholesterolemic activity of soybean protein as compared with casein is known to be due to suppression of intestinal cholesterol absorption, 5,6) promotion of fecal steroid excretion, [7][8][9][10] increases in the cholesterol removal rate through the LDL receptor, 1,3,4) and so on. 11,12) Soybean protein has also been found to have triglyceride-lowering action.…”

“…It has been reported that soybean peptides also have a hypocholesterolemic effect. [7][8][9][10] This is because the peptides contain a high-molecular-weight (undigested) fraction, which is responsible for the stimulation of fecal steroid excretion, [7][8][9][10] but the effects of soybean peptides containing a low-molecular-weight (digested) fraction on cholesterol metabolism are unclear. Also, no consistent results have been obtained for the effect of soybean peptides on triglyceride metabolism.…”

Papain-Hydrolyzed Pork Meat Reduces Serum Cholesterol Level and Premature Atherosclerosis in Dietary-Induced Hypercholesterolemic Rabbits.

“…In animals and humans, soy protein has been shown to be more effective than casein at reducing the serum cholesterol level (1)(2)(3)(4)(5). After Sugano et al (5,6) had found that a protease hydrolyzate of isolated soy protein had a more marked hypocholesterolemic effect than undigested soy protein, Morimatsu et al (7,8) reported that a papain hydrolyzate of pork meat produced a greater suppression of the plasma cholesterol level than soy protein did in rats with dietary-induced hypercho lesterolemia. The rat, however, is less sensitive to a cho lesterol-rich diet than the rabbit is, and it is difficult to induce a distinct atherosclerosis in the former species (9,10).…”