Influences of dietary high-amylose cornstarch(HAS), on mucin and Immunoglobulin A (IgA) secretions in ratgastrointestinal tract were examlned. In experlment I , rats werefed a purified diet (control) or diet containing 15% or 30% of HASfor 10 days. Mucin as well as lgA contents in the small intestine,cecum and feces were dose-dependently increased in rats fed the HASdiet. In experiment 2, rats were fed a purified diet or dietcontaining either 30% HAS, 6% fructooligosaccharide (FOS) or 5%powdered polystyrene foam (PSF) for 9 days. Mucin content in thesmall intestine was increased by the ingestion of HAS or PSF diet,but not by FOS diet. In contrast, mucin in cecal mL[cosa was muchgreater in rats fed the HAS and FOS diets than in those fed thecontrol or PSF diet. Greater cecal lgA content was observed in ratsfed the HAS and FOS diets compared with those fed the control andPSF diets, whereas lgA contents in the small intestine and feceswere manifest only in rats fed the HAS diet. The results suggestthe vlew that dietary resistant starch enhances mucin and lgAsecretions in the gastrointestinal tract at least by two differentfactors, i.e., bulk effects on mucin and lgA secretion. and largebowel fermentability also affects cecal mucin and lgAsecretion.
Key words: high-amylose cornstarch, Iuminal bulk formation, Iargebowel fermentation, Iuminal mucin, Immunoglobulin A, rats |
