Ye Jingsong, Shakya Roshani, Shrestha Pradeep, Rommens Caius M
Department of Plant Sciences, JR Simplot Company, Boise, Idaho 83706, United States.
J Agric Food Chem. 2010 Dec 8;58(23):12162-7. doi: 10.1021/jf1032262. Epub 2010 Nov 4.
Some popular processed foods including French fries contain small amounts of toxic acrylamide. Efforts to lower the accumulation of this reactive compound by modifying the production process have a negative effect on sensory characteristics and are not broadly applicable. This study optimized a method developed more than a decade ago to lower the accumulation of the acrylamide precursors glucose and fructose in cold-stored tubers. In contrast to the original application, which lowered hexose content by one-third through constitutive expression of an antisense copy of the cold-inducible acid invertase (Inv) gene, the current approach was based on tuber-specific expression of an Inv-derived inverted repeat. Stored tubers of transgenic plants contained as little as 2% of the reducing sugars that accumulated in controls. This decline in glucose and fructose formation is counterbalanced by increased sucrose and starch levels. However, it did not trigger any phenotypic changes and also did not affect the formation of free asparagine, ascorbic acid, phenylalanine, and chlorogenic acid. Importantly, French fries from the low-invertase tubers contained up to 8-fold reduced amounts of acrylamide. Given the important role of processed potato products in the modern Western diet, a replacement of current varieties with the low-hexose potatoes would reduce the average daily intake of acrylamide by one-fourth.
一些受欢迎的加工食品，包括薯条，含有少量有毒的丙烯酰胺。通过改进生产工艺来降低这种活性化合物积累的努力，对感官特性有负面影响，且无法广泛应用。本研究优化了一种十多年前开发的方法，以降低冷藏块茎中丙烯酰胺前体葡萄糖和果糖的积累。与最初通过组成型表达冷诱导酸性转化酶（Inv）基因的反义拷贝使己糖含量降低三分之一的应用不同，目前的方法基于Inv衍生反向重复序列的块茎特异性表达。转基因植物的储存块茎中积累的还原糖仅为对照的2%。葡萄糖和果糖形成的这种下降被蔗糖和淀粉水平的增加所抵消。然而，它并未引发任何表型变化，也不影响游离天冬酰胺、抗坏血酸、苯丙氨酸和绿原酸的形成。重要的是，来自低转化酶块茎的薯条中丙烯酰胺含量减少了多达8倍。鉴于加工马铃薯产品在现代西方饮食中的重要作用，用低己糖马铃薯取代现有品种将使丙烯酰胺的平均每日摄入量减少四分之一。
