Preparation of tartary buckwheat protein product and its improving effect on cholesterol metabolism in rats and mice fed cholesterol-enriched diet.
Tartary buckwheat protein product (TBP) was prepared from buckwheat flour by alkali extraction and isoelectric precipitation. The protein content of TBP was 45.8%, and its amino acid composition of TBP was similar to that of common buckwheat protein product (BWP). SDS-PAGE analysis showed that the protein profile of TBP was partially different from that of BWP. TBP contained more quercetin (1710 mg/100 g) than BWP (5.4 mg/100 g), while there was a small difference in the contents of rutin between them. In experiment 1, the consumption of BWP and TBP at 20% net protein level for 13 d caused 32% and 25% reductions in serum cholesterol of rats fed cholesterol, respectively, when compared to the consumption of casein (P < 0.05). The reduction of serum cholesterol by BWP and TBP was associated with enhanced excretion of fecal neutral sterols. In experiment 2, the consumption of BWP and TBP for 27 d caused 62% and 43% reductions in the lithogenic index in mice fed cholesterol, respectively (P < 0.05). The reduction in lithogenic index was associated with enhanced excretion of fecal bile acids. Taken together, these results suggest a potential source of TBP as a functional food ingredient as well as BWP.
Tomotake
H
H
Iida Women's Junior College, Iida, 395-0812, Japan. tomotake@iidawjc.ac.jp
Yamamoto
N
N
Kitabayashi
H
H
Kawakami
A
A
Kayashita
J
J
Ohinata
H
H
Karasawa
H
H
Kato
N
N
D000818:Animals; D000924:Anticholesteremic Agents / Q000008:administration & dosage / Q000494:pharmacology; D002784:Cholesterol / Q000097:blood / Q000378:metabolism*; D002791:Cholesterol, Dietary / Q000493:pharmacokinetics*; D004591:Electrophoresis, Polyacrylamide Gel; D019612:Fagopyrum / Q000737:chemistry*; D005243:Feces / Q000737:chemistry; D005511:Food Handling / Q000379:methods*; D058870:Food, Organic; D006937:Hypercholesterolemia / Q000188:drug therapy / Q000517:prevention & control; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009753:Nutritive Value; D010940:Plant Proteins / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology*; D011794:Quercetin; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012431:Rutin; D013261:Sterols / Q000032:analysis
D000924:Anticholesteremic Agents; D002791:Cholesterol, Dietary; D010940:Plant Proteins; D013261:Sterols; D012431:Rutin; D002784:Cholesterol; D011794:Quercetin