In Vitro Synthesis of Betaxanthins Using Recombinant DOPA 4,5-Dioxygenase and Evaluation of Their Radical-Scavenging Activities
作者:Hiroshi Sekiguchi、Yoshihiro Ozeki、Nobuhiro Sasaki
DOI:10.1021/jf1030086
日期:2010.12.8
for proline-betaxanthin. Twenty-four betaxanthin species were synthesized by the condensation reaction of purified betalamic acid and amino acids or amines. An HPLC protocol was established for identifying the different betaxanthin species. Proline-, dopamine-, and γ-aminobutyric acid (GABA)-betaxanthins were prepared as representative betaxanthins under large-scale conditions, and their 1,1-diphe
使用重组Mirabilis jalapa从1-二羟基苯丙氨酸(L-DOPA)大规模酶促合成了虾青素的发色团β-丙二酸。DOPA 4,5-二加氧酶。合成后,将脯氨酸直接添加到浓缩的反应混合物中以生成脯氨酸-甜菜黄素。纯化产物的分子量和核磁共振谱与先前报道的脯氨酸-甜菜黄素的分子量和核磁共振谱相同。通过纯化的铍金属与氨基酸或胺的缩合反应合成了二十四种虾青素。建立了用于鉴定不同虾青素种类的HPLC方案。在大规模条件下,制备了脯氨酸,多巴胺和γ-氨基丁酸(GABA)-甜菜黄素作为代表性的虾青素,并将它们的1,1-二苯基-2-吡啶并肼基自由基清除活性与已知的抗氧化剂进行了比较。GABA-甜菜黄素显示相对较低的活性,而多巴胺-甜菜黄素的活性与红色素甜菜碱和花青素花青素3-葡糖苷相似。脯氨酸-β-黄嘌呤具有三种合成化合物中最高的活性,与类黄酮槲皮素相似。