ARS | Publication request: Genotypic variation in wheat grain fructan content revealed by a simplified HPLC method

Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 25, 2007
Publication Date: N/A

Interpretive Summary: Poor gut health affects the health and nutritional status of over 2 billion people worldwide by reducing their ability to absorb nutrients from their diet and to resist pathogenic gut bacterial infection. Some non-digestible carbohydrates (i.e., prebiotics) affect gut health by stimulating beneficial bacterial growth in the colon. Inulin (a fructooligosaccharide) is one such carbohydrate present in wheat grain. Ways need to be found to increase the amount of inulin in wheat grain to improve gut health. One such way is to breed for high inulin wheat grain. We developed a new method to determine the amount of inulin in wheat grain and used this method to determine the genetic variation in inulin levels in different lines of wheat grain. There was significant genotypic variation in inulin levels in wheat grain varying from 0.7 to 2.9%. Thus, it appears possible to select for high inulin wheat in wheat breeding programs. There was also a significant effect of the environment on inulin levels in wheat grain

Technical Abstract: Fructans are regarded as prebiotics, with potentially beneficial effects on human health. This study aimed to examine genetic variation in wheat grain fructan content using an improved analytical method. The method involves extracting fructans from wheat grain followed by enzymatic hydrolysis to break down fructans into monosaccharides that can then be quantitatively measured by anion-exchange liquid chromatography coupled with pulsed amperometric detection. The modified procedure is reliable and allows the handling of large numbers of flour samples at a low cost, and could therefore be useful for assessing large numbers of wheat breeding lines. Using this method, grain samples taken from 19 bread wheat cultivars and breeding lines grown in both glasshouse and the field were analysed for grain fructan content. In addition, grain samples of 29 wheat landraces and 14 new CIMMYT wheat breeding lines were surveyed for their fructan contents. There was significant genotypic variation among these materials, with grain fructan content ranging from 0.7 to 2.9% of grain dry weight and an apparent low G x E effect was observed. It should therefore be possible to improve grain fructan content by traditional wheat breeding, and to investigate the genetic control of variation for this trait using the simplified HPLC method.