MEASURING DIETARY FIBER

拟议研究的长期目标是阐明 膳食纤维的作用机制。 有些是后果 在他的作品中，有一个人，他的作品，有一个人， 代谢，主要发生在大肠， 微生物群落的作用。 然而，微生物的活动将取决于 根据可用的衬底。 纤维对小肠的影响 消化酶活性，内腔内容物的粘度， 转运速率和粘蛋白分泌都影响底物 可用于发酵。 本申请的主要目的是 研究膳食纤维代谢的性质和程度， 胃肠道中的其他底物，并开始检查 从这些基质释放的能量的分布 细菌和短链脂肪酸之间的联系 方法 描述膳食纤维的特性，并将其与其他 肠内腔内容物中的多糖源，即细菌， 粘蛋白和未消化的食物碳水化合物是 我们的研究 这些方法将用于确定 膳食纤维代谢的研究 清醒的小型猪与套管手术植入在不同的 在胃肠道中的位置。 基质比例 用于细菌生长和代谢，将通过 测量细菌量和芽孢杆菌的消失。 能源 将通过测量短链来评估可吸收性 在体外培养过程中产生的脂肪酸。 我们 假设可溶性纤维和粘蛋白将迅速 在近端结肠发酵，不溶性纤维将 主要在远端结肠中代谢。 本研究将 解决几个重大的人类健康问题，包括 足够的膳食纤维在治疗肥胖和糖尿病 糖尿病和动脉粥样硬化的过程。 本研究也 将检验纤维影响结肠癌发生的假设， 部分通过改变底物来改变微生物代谢， 可用于发酵。

The longterm goal of the proposed research is to elucidate the mechanisms of action of dietary fiber. Some are a consequence of its presence in the gut; others are undoubtedly a result of its metabolism, which occurs principally in the large bowel through the action of microflora. Microbial activity will, however, depend upon the substrates available. The effects of fiber on small bowel digestive enzyme activities, the viscosity of the lumenal contents, the rate of transit and mucin secretion all influence the substrate available for fermentation. The primary aim of this application is to study the nature and extent of metabolism of dietary fiber and other substrates in the gastrointestinal tract and begin to examine the distribution of the energy released from these substrates between bacteria and short chain fatty acids. Methods to characterize dietary fiber and to distinguish it from other polysaccharide sources in gut lumenal contents, i.e. bacteria, mucins and undigested food carbohydrate, are a major focus of our research. These methods will be used to determine the metabolism of dietary fiber by analyzing digesta collected from conscious minipigs with cannulas surgically implanted at different sites in the gastrointestinal tract. The proportion of substrate used for bacterial growth and metabolism will be evaluated by measuring bacterial mass and disappearance of digesta. Energy available for absorption will be assessed by measuring short chain fatty acids produced during in vitro incubation of digesta. We hypothesize that soluble fibers and mucin will be rapidly fermented in the proximal colon and that insoluble fiber will be metabolized principally in the distal colon. This study will address several significant human health issues, including the role of adequate dietary fiber in the treatment of obesity and diabetes mellitus and in the process of atherogenesis. This research also will test the hypothesis that fiber affects colon carcinogenesis by modifying microbial metabolism, in part, by altering the substrate available for fermentation.