Larsen F M, Wilson M N, Moughan P J
Department of Chemistry and Biochemistry, Massey University, Palmerston North, New Zealand.
J Nutr. 1994 Jun;124(6):833-41. doi: 10.1093/jn/124.6.833.
The effect of dietary fiber viscosity on apparent ileal nitrogen and amino acid digestibility, proteolytic enzyme activity and digestive organ weights was investigated. Eighteen growing rats were fed for 21 d purified casein-based diets containing carboxymethylcellulose (50 g/kg) of low (20 cP), medium (800 cP) and high (2000 cP) viscosity (LV, MV and HV treatment groups, respectively). Dietary fiber viscosity did not significantly affect apparent ileal (terminal 15 cm of the ileum) nitrogen or amino acid digestibility, trypsin or chymotrypsin activity in the small intestinal contents and pancreatic tissue, aminopeptidase-N activity in the small intestinal contents and tissue, or the weights of the stomach, pancreas, small or large intestines. Intragastric pepsin activity in LV rats was significantly higher than in MV or HV rats (P < 0.01), but fiber viscosity did not affect pepsin activity in the stomach tissue. The intragastric pH of the HV and MV rats was significantly higher than that for the LV rats (P < 0.01). The stomach contents (dry matter) of MV and HV rats were greater than in LV rats (P < 0.05). Delayed passage rate of the more viscous digesta may have resulted in greater absorption of amino acids, because the HV rats had a higher estimated true ileal digestibility than the LV animals for threonine, serine, aspartic acid, glutamic acid, histidine, tyrosine and phenylalanine.
研究了膳食纤维粘度对回肠表观氮和氨基酸消化率、蛋白水解酶活性及消化器官重量的影响。选用18只生长大鼠，分别饲喂基于酪蛋白的纯化日粮21天，日粮中含有低粘度（20厘泊）、中粘度（800厘泊）和高粘度（2000厘泊）的羧甲基纤维素（分别为低粘度、中粘度和高粘度处理组）。膳食纤维粘度对回肠末端（回肠末端15厘米）表观氮或氨基酸消化率、小肠内容物和胰腺组织中的胰蛋白酶或糜蛋白酶活性、小肠内容物和组织中的氨肽酶-N活性，以及胃、胰腺、小肠或大肠的重量均无显著影响。低粘度组大鼠的胃内胃蛋白酶活性显著高于中粘度组或高粘度组大鼠（P<0.01），但纤维粘度对胃组织中的胃蛋白酶活性无影响。高粘度组和中粘度组大鼠的胃内pH值显著高于低粘度组大鼠（P<0.01）。中粘度组和高粘度组大鼠的胃内容物（干物质）多于低粘度组大鼠（P<0.05）。粘性较高的食糜通过速率延迟可能导致氨基酸吸收增加，因为高粘度组大鼠对苏氨酸、丝氨酸、天冬氨酸、谷氨酸、组氨酸、酪氨酸和苯丙氨酸的回肠真消化率估计值高于低粘度组动物。
