enolizable groups to form pyranoanthocyanins. These pigments are less susceptible to degradation and color changes associated with nucleophilic addition common to anthocyanins. This study aimed to evaluate the impact of glycosylation patterns of anthocyanins on carboxypyranoanthocyanin formation. Nine cyanidin derivatives were isolated by semi-preparative HPLC. Pyruvic acid was added to induce pyranoanthocyanin
花青素可与具有可烯丙基的化合物缩合形成
吡喃
花青素。这些
颜料较不容易降解和变色,这与花色苷常见的亲核加成有关。这项研究旨在评估花色苷的糖基化方式对羧基
吡喃
花青素形成的影响。通过半制备HPLC分离了九种
花色素衍
生物。添加
丙酮酸以诱导
吡喃
花青素形成。在25°C下储存31天期间,监测溶液的组成(HPLC-MS / MS),光谱(吸光度380-700 nm)和颜色(CIEL * c * h *)。带有1→6个二糖的
氰基-3-糖苷产生最高的
吡喃
花色素苷产率(〜31%),其次是
氰基-3-
单糖苷(〜20%);1→2二糖产生的
吡喃
花青素比例最低(5-7%)。Cyanidin-3-arabinoside转化为
吡喃
花色素,但在这些条件下迅速降解(3%产率)。由
氰胺丁-3-
槐糖苷-5-
葡糖苷未形成
吡喃
花色素苷。糖基键比单独取代的大小更关键,而Cyanidin-3-(
葡萄糖基)-(1→6)-(
木糖基-(1→2)-半