Identification of Two Novel Pigment Precursors and a Reddish-Purple Pigment Involved in the Blue-Green Discoloration of Onion and Garlic
作者:Shinsuke Imai、Kaori Akita、Muneaki Tomotake、Hiroshi Sawada
DOI:10.1021/jf0519818
日期:2006.2.1
By using a model reaction system representing blue-green discoloration that occurs when purees of onion (Allium cepa L.) and garlic (Allium sativum L.) are mixed, we isolated two pigment precursors (PPs) and a reddish-purple pigment (PUR-1) and determined their chemical structures. PPs were isolated from a heat-treated solution containing color developer (CD) and either l-valine or l-alanine, and their
通过使用表示洋葱(Allium cepa L.)和大蒜(Allium sativum L.)的浆液混合时发生的蓝绿色变色的模型反应系统,我们分离了两种颜料前体(PPs)和红紫色颜料(PUR -1)并确定其化学结构。从含有彩色显影剂(CD)和l-缬氨酸或l-丙氨酸的热处理溶液中分离PPs,并确定其结构为2-(3,4-二甲基吡咯基)-3-甲基丁酸(PP-Val)分别是2-(3,4-二甲基-1H-吡咯基)丙酸(PP-Ala)。接下来,从包含PP-Val和大蒜素的热处理溶液中分离出PUR-1,并确定其结构为(1E)-1-(1-(((1S)-1-羧基-2-甲基丙基)-3) ,4-二甲基-1H-吡咯-2-基)-丙-1-烯-3-(1-(((1S)-1-羧基-2-甲基丙基)-3,4-二甲基-1H-吡咯- 2-y)。PUR-1的结构表明,含有3,4-二甲基吡咯环的PP分子已被大蒜素的烯丙基交联形成共轭颜料。