Improving health benefits of wheat by increasing resistant starch

描述（由申请人提供）：糖尿病和肥胖症是一个日益严重的公共卫生问题，每年影响越来越多的人口。很大一部分人处于糖尿病前期，有可能向糖尿病发展。食物选择会影响所有这些健康问题。这项提议的总体目标是增加小麦中的抗性淀粉含量，小麦是我们饮食的主要组成部分。抗性淀粉有许多有益健康的特性。它是淀粉的一部分，没有在下肠消化，而是在大肠发酵。正因为如此，抗性淀粉不会导致餐后葡萄糖迅速上升；相反，葡萄糖释放到血液中的速度更慢，导致饱腹感增加。下肠中抗性淀粉的发酵也会导致短链脂肪酸的产生，有助于促进结肠健康。我们建议开发具有很高抗性淀粉水平的小麦新品种。通过增加直链淀粉（淀粉的成分之一）的含量，抗性淀粉的含量也会增加。抗性淀粉也与总膳食纤维水平相关，因为它被缓慢消化；所以增加的直链淀粉也增加了纤维含量。在前期工作中，我们利用TILLING （Targeting Induced Local lesion In Genomes）技术，通过改变淀粉生物合成途径中的一种酶，培育出了直链淀粉水平适中的小麦品系。TILLING是一种新型的非转基因（基因修饰）技术，是一种靶向选择的突变育种。为了开发高直链淀粉小麦产品，我们建议结合连锁淀粉生物合成基因的突变。获得必要的连锁突变的可行性将在第一阶段进行验证。考虑到我们的小麦TILLING文库的大小和突变频率，这个项目有很高的成功可能性。其余的必要突变将在第二阶段被发现，并通过育种组合产生非常高的直链淀粉品种。基于我们初步数据的强度和商业化的高可能性，我们已经申请了快速通道SBIR，因为抗性淀粉的来源比目前可用的食物要多，而抗性淀粉的使用是有限的。因为业界对这个产品的兴趣程度。高抗性淀粉小麦可以纳入小麦是普遍存在于我们的饮食，这种产品可能对健康有重大的积极影响。

DESCRIPTION (provided by applicant): The conditions of diabetes and obesity are a growing public health concern affecting more of the population every year. A large segment of the population is pre-diabetic potentially progressing towards diabetes. Food choices impact all of these health problems. The overall goal of this proposal is to increase resistant starch levels in wheat, a principle part of our diet. Resistant starch has many beneficial health properties. It is the portion of starch that escapes digestion in the lower intestine and is instead fermented in the large intestine. Because of this, resistant starch does not cause a rapid rise in glucose after a meal; instead glucose is released more slowly into the bloodstream and leads to an increased feeling of satiety. Fermentation of resistant starch in the lower intestine also leads to short chain fatty acid production that helps promote colon health. We propose to develop novel wheat cultivars with very high levels of resistant starch. By increasing levels of amylose, one of the components of starch, resistant starch levels increase. Resistant starch is also correlated with levels of total dietary fiber because it is slowly digested; so increased amylose increases fiber content as well. In preliminary work, we developed a wheat line with moderate amylose levels due to the alteration of an enzyme in the starch biosynthetic pathway using TILLING (Targeting Induced Local Lesions in Genomes). TILLING is a novel non-GM (genetic modification) technique that is a target-selected variation of mutation breeding. In order to develop very high amylose wheat for a product that can be commercialized, we propose to combine mutations in linked starch biosynthetic genes. The feasibility of obtaining the necessary linked mutations will be demonstrated during Phase I. This project has a high likelihood of success given the size and mutation frequency of our wheat TILLING library. The rest of the necessary mutations will be discovered during Phase II and combined through breeding to produce the very high amylose variety. We have applied for the Fast Track SBIR based on the strength of our preliminary data and the high likelihood of commercialization due to the many more foods than currently available sources of resistant starch whose use is limited. Because level of interest from the industry in this product. High resistant starch wheat can be incorporated into wheat is pervasive in our diets, this product could have a major positive impact on health. PUBLIC HEALTH RELEVANCE: The conditions of diabetes and obesity are a growing public health concern affecting more of the population every year. Food choices impact these health problems, and foods high in resistant starch have beneficial effects that help combat these conditions. The overall goal of this proposal is to develop novel wheat cultivars with very high levels of resistant starch that would positively impact health. )