MEASURING DIETARY FIBER

测量膳食纤维

• 批准号: 2137599
• 负责人: JUDITH A. MARLETT
• 金额: $ 24.12万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-12-01 至 1996-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2137599
• 关键词: antihypercholesterolemic agent; bioenergetics; biological models; carcinogenesis inhibitor; colon; colon neoplasms; colon surgery; dietary fiber; digestion; enteric bacteria; feces analysis; fermentation; gas chromatography; gastrointestinal nutrient absorption; gastrointestinal system; gel filtration chromatography; intestinal mucosa; laboratory rat; microorganism growth; microorganism metabolism; miniature swine; model design /development; mucins; nutrient bioavailability; nutrition related tag; starch

Different dietary fiber (DF) sources elicit different physiological responses. The long term goal of this research program is to elucidate the mechanisms of action for dietary fiber. Giber's effects on the physiology and biochemistry in the gastrointestinal tract are a consequence of both its presence and its metabolism. However, net fermentation and the presence of undigested DF do not explain its effect on stool weight. DF is implicated in colon carcinogenesis, although its role is controversial in part because epidemiological and experimental data have been inconsistent. Absorption of fermentation products, short chain fatty acids (SCFA), has been demonstrated, although no DF is currently assigned a caloric value. The overall aim of this competing renewal is to determine the site, rate and extent of fermentation in monogastric species to test the hypotheses that is the rate, site and extent of fermentation and its effect on microbial growth and metabolism that determine which DF sources will increase stool weight, inhibit toxic or carcinogenic metabolic activity or provide net energy to the host. DF's rate of fermentation can be predicted in part by its solubility, although current analytic methods underestimate soluble DF reaching the colon. Some data indicate that DF affects secretion of small bowel mucin. Other data indicate that starch assimilation from legumes and processed grain products is incomplete. The relative proportion of soluble DF, mucin and starch reaching the colon will be determined as they would confound the relationships between DF fermentation and stool weight, microbial metabolism and net energy bioavailability. Experiments will be conducted in intact and colectomized rats, and in swine with cannulas chronically implanted in the gut. Plant-, bacterially- and endogenously-derived CHO will be distinguished on the basis of solubility, size and neutral and amino sugar composition. Relative rates and ratios of SCFA production will be determined to clarify proposed roles of SCFA in mucosal cell growth and in inhibiting hepatic cholesterol synthesis. Results from the proposed research will define optimal DF sources for the prevention and treatment of constipation and diverticulosis, and possibly for hypercholesterolemia and colon cancer. These experiments will provide evidence that some DF should be assigned caloric values and may need to be considered as energy sources in diabetic and weight reduction diets and products.

不同的膳食纤维（DF）来源会产生不同的生理作用 回应。 该研究计划的长期目标是阐明 膳食纤维的作用机制。 吉伯的影响 胃肠道的生理学和生物化学是 它的存在和新陈代谢的结果。 然而，网 发酵和未消化的 DF 的存在并不能解释其效果 关于粪便重量。 DF 与结肠癌发生有关，尽管它 其作用存在争议，部分原因是流行病学和实验 数据一直不一致。 发酵产物的吸收，短 链脂肪酸（SCFA），已被证明，尽管没有 DF 当前分配了一个热量值。 本次竞赛的总体目标 更新是确定发酵的地点、速率和程度 单胃物种来检验假设，即速率、地点和 发酵程度及其对微生物生长和代谢的影响 确定哪些 DF 来源会增加粪便重量、抑制有毒物质 或致癌代谢活动或为宿主提供净能量。 DF 的发酵速率可以部分通过其溶解度来预测， 尽管目前的分析方法低估了可溶性 DF 达到 冒号。 一些数据表明DF影响小肠的分泌 粘蛋白。 其他数据表明，来自豆类和 粮食加工产品不全。 的相对比例 到达结肠的可溶性 DF、粘蛋白和淀粉将确定为 他们会混淆 DF 发酵和粪便之间的关系 体重、微生物代谢和净能量生物利用度。 实验 将在完整的结肠切除大鼠和猪中进行 长期植入肠道的插管。 植物、细菌和 内源衍生的 CHO 的区分依据是 溶解度、大小以及中性和氨基糖的组成。 相对比率 将确定短链脂肪酸 SCFA 的生产比例，以澄清拟议的 SCFA 在粘膜细胞生长和抑制肝脏中的作用 胆固醇合成。 拟议研究的结果将定义 预防和治疗便秘的最佳 DF 来源 憩室病，并可能导致高胆固醇血症和结肠癌。 这些实验将提供证据表明应该分配一些 DF 热量值，可能需要被视为能量来源 糖尿病和减肥饮食和产品。