Characterization by HPLC-ESI-MS2 of native and oxidized procyanidins from litchi (Litchi chinensis) pericarp
Characterization by HPLC-ESI-MS2 of native and oxidized procyanidins from litchi (Litchi chinensis) pericarp
复制标题
荔枝果皮原花青素及其氧化产物的HPLC-ESI-MS 2表征
DOI：
10.1016/j.foodchem.2019.04.020
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发表时间：
2019-09-01
期刊：
影响因子：
8.8
通讯作者：
Aguilar, Cristobal N.
中科院分区：
文献类型：
--
作者：
Miranda-Hernandez, Angela M.;Muniz-Marquez, Diana B.;Aguilar, Cristobal N.
原花青素（Procyanidins，PC）是荔枝果实中含量较高的多酚类物质。尽管具有生物活性，但天然和氧化原花青素的分子组成仍知之甚少。采用甲醇和丙酮两种溶剂提取荔枝果皮多酚。分别采用间苯三酚和巯基乙酸水解-HPLC-ESI-MS/MS法测定天然PC的平均聚合度（mDP）和氧化PC的鉴定。荔枝果皮多酚类物质中约60%为原花青素。天然PC主要是低聚原花青素（mDP 4）。只有（-）-表儿茶素被检测到作为终端和延伸单位的PC。硫代糖酵解-HPLC-ESI-MS鉴定了PC的5种氧化标志物，[M-H]（-）m/z为575、593、609、679和863。A型和B型原花青素的分子内和分子间修饰被鉴定。用于表征的方法，从荔枝果皮PC允许了解其天然和氧化单宁的结构组成。
Procyanidins (PCs) are polyphenols highly accumulated in litchi fruit (Litchi chinensis). Despite their bioactivity, the molecular composition of native and oxidized procyanidins is little understood. In this paper, polyphenols from litchi pericarp were extracted using two solvents (methanol and acetone). The mean degree of polymerization (mDP) of native and identification of oxidized PCs were carried out by phloroglucinolysis- and thioglycolysis-HPLC-ESI-MS/MS, respectively. About 60% of extracted polyphenols corresponded to procyanidins from litchi pericarp. Native PCs were mainly oligomeric procyanidins (mDP 4). Only (-)-epicatechin was detected as terminal and extension units in PCs. Thioglycolysis-HPLC-ESI-MS identified five oxidation markers of PCs with [M - H](-) m/z 575, 593, 609, 679 and 863. Intra- and intermolecular modifications of A and B-type procyanidins were identified. The method used for the characterization of PCs from litchi pericarp allowed understanding of the structural composition of its native and oxidized tannins.