落叶松原花青素的没食子酰化及其抗氧化活性增强效应

Galloylation of Procyanidin from Larch Bark and Its Enhancement Effects on Antioxidant Activity

对落叶松树皮提取分离的原花青素(PC)进行没食子酰化反应,在其分子结构中引入具有邻三酚羟基的没食子酰基,获得改性产物没食子酰化原花青素(GPC)。红外光谱分析表明:PC经过没食子酰化反应,产物GPC形成了原花青素没食子酯的结构,羟基的数量得到增加。通过HPLC法测定产物GPC水解后生成的没食子酸量,计算其没食子酰化度为63%。测定比较了PC和GPC对DPPH自由基(DPPH.)的清除能力以及对过渡金属离子的络合能力和对油脂抗氧化性能的效果。结果表明原花青素经过没食子酰化后,其改性产物的抗氧化活性得到显著增强。

Galloylation of procyanidin was carried out using procyanidins（PC） separated from larch bark as raw material.Galloyl groups were inserted into procyanidin molecule based on esterification,and galloylated procyanidins（GPC）were obtained consequently.It was showed that galloylation had taken place and number of hydroxyls in molecule had increased from FT-IR spectra of PC and its galloylated product.Through estimation of gallic acid quantity in product hydrolysate by HPLC method,the galloylation degree was 63 %.Furthermore the researches on biological activity difference between PC and GPC were carried out through estimation of radical-scavenging activity and complexation ability for transition metal ions,as well as antioxidation ability toward fat,showing that the biological activity of procyanidin after galloylation was enhanced observably.