α-二羰基类化合物与L-亮氨酸组成模型体系的Strecker降解反应研究  

Investigation of Strecker Degradation in Model Systems Consisting of Alpha-Dicarbonyls and L-Leucine

作　　者：田红玉[1] 孙宝国[1] 张洁[1] 黄明泉[1] 

机构地区：[1]北京工商大学化学与环境工程学院,北京100037

出　　处：《食品科学》2010年第4期24-27,共4页Food Science

基　　金：北京市新世纪百千万人才工程培养经费资助项目;国家自然科学基金项目(20676003)

摘　　要：通过研究乙二醛、丙酮醛和丁二酮分别与L-亮氨酸组成的模型体系中异戊醛形成的情况,以比较典型的糖类降解产物乙二醛、丙酮醛和丁二酮在L-亮氨酸发生Strecker降解反应中的作用。通过α-二羰基化合物和L-亮氨酸在高压釜中的磷酸盐缓冲溶液中反应,采用正交试验考察投料比(α-二羰基化合物和L-亮氨酸物质的量比)、温度及pH值对异戊醛产率的影响。结果表明,3种α-二羰基类化合物中乙二醛体系形成的异戊醛最多,当乙二醛与L-亮氨酸的物质的量比为6:1,pH5,在140℃条件下反应3h,异戊醛产率可达24%左右;而丙酮醛和丁二酮在最佳条件下反应,异戊醛的产率都只有14%左右。对于L-亮氨酸发生的Strecker降解反应,乙二醛反应活性最高,最有利于异戊醛的形成。对于乙二醛与L-亮氨酸组成的模型体系,影响反应的各因素中pH值对异戊醛形成产生最明显的影响,酸性条件更有利于异戊醛的形成。As typical degradation products of carbohydrates,alpha-dicarbonyls including glyoxal,pyrualdehyde and butandione were individually used for comprising model systems with L-leucine to investigate their roles in the formation of isovaleraldehyde in the Strecker degradation of L-leucine.A high pressure vessel was used for the reaction between alphadicarbonyls and L-leucine in phosphate buffer solution and the effects of molar ratio of reactants,temperature and pH value on isovaleraldehyde yield were examined using orthogonal array design.Results showed that among three alpha-dicarbonyls,the system containing glyoxal gave the highest isovaleraldehyde yield of around 24% under the reaction conditions of 140 ℃,pH 5 and 6：1 molar ratio of glyoxal to L-leucine,while isovaleraldehyde yield was only around 14% when pyrualdehyde or butandione was used instead of glyoxal.This demonstrates the highest reactivity of glyoxal for the formation of isovaleraldehyde.Among three reaction conditions tested,pH had the most obvious effect,and an acidic condition favored the formation of isovaleraldehyde.

关 键 词：L-亮氨酸 α-二羰基类化合物 Strecker降解 异戊醛 

分 类 号：TS201.23[轻工技术与工程—食品科学]