Reed Jess D, Krueger Christian G, Vestling Martha M
Department of Animal Science and Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
Phytochemistry. 2005 Sep;66(18):2248-63. doi: 10.1016/j.phytochem.2005.05.015.
The structural heterogeneity of polyphenols from cranberries, grape seed extracts, sorghum and pomegranate was characterized by MALDI-TOF MS. Polyphenolics were isolated by liquid chromatography and subjected to MALDI-TOF MS using trans-3-indoleacrylic acid as the matrix. Spectrometric analysis gave information on degree of polymerization, monomeric substitution, and the nature of intermolecular bonds. Cranberry polyflavan-3-ols had variation in interflavan bonds (A- and B-types) and contained polyflavan-3-ols linked to anthocyanins through a CH3-CH bridge. Polygalloyl-polyflavan-3-ols in grape seed extract had large variation in the degree of galloyl substitution. Sorghum polyflavans had structural heterogeneity in glycosylation and hydroxylation. Pomegranate hydrolyzable tannins that correspond to previously described structures were detected, such as punicalagin, but others that correspond to oligomeric ellgitannins in which two to five core glucose units are cross-linked by dehydrodigalloyl and or valoneoyl units were also observed. Results demonstrate that large heterogeneity occurs in degree of polymerization, intermolecular bonds, pattern of hydroxylation, and substitution with monosaccharides and gallic acid.
采用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）对蔓越莓、葡萄籽提取物、高粱和石榴中的多酚类物质的结构异质性进行了表征。通过液相色谱法分离多酚类物质，并以反式-3-吲哚丙烯酸为基质对其进行MALDI-TOF MS分析。光谱分析提供了有关聚合度、单体取代以及分子间键性质的信息。蔓越莓中的聚黄酮-3-醇在黄酮间键（A-型和B-型）上存在差异，并且含有通过CH3-CH桥与花青素相连的聚黄酮-3-醇。葡萄籽提取物中的聚没食子酰基聚黄酮-3-醇在没食子酰基取代程度上有很大差异。高粱中的聚黄酮在糖基化和羟基化方面存在结构异质性。检测到了与先前描述结构相对应的石榴可水解单宁，如石榴皮素，但也观察到了其他与低聚鞣花单宁相对应的物质，其中两到五个核心葡萄糖单元通过脱氢二没食子酰基和/或戊二酰基单元交联。结果表明，在聚合度、分子间键、羟基化模式以及单糖和没食子酸取代方面存在很大的异质性。
