Division of Biotechnology, Department of Chemistry, Lund University, P.O. Box 124, 221 00 Lund, Sweden.
Centre for Analysis and Synthesis, Department of Chemistry, Lund University, P.O. Box 118, 221 00 Lund, Sweden.
Molecules. 2020 Dec 23;26(1):43. doi: 10.3390/molecules26010043.
Phlorotannins are bioactive polyphenols in brown macroalgae that make these algae interesting as healthy food. Specific phlorotannins are, however, seldom identified, and extracts from different species are often only analysed for total phenolic content (TPC). In this study, our focus was to identify phlorotannin molecules from and (a species rich in these compounds) using ultra-high-performance liquid chromatography coupled to high-resolution tandem mass spectrometry (UHPLC-HRMS). Water and ethanol (30 and 80% /) were used at solid:liquid ratios, extraction times and temperatures, proposed to result in high TPC in extracts from other species. The extracts, however, did not allow phlorotannin detection by either UHPLC-UV/Vis or UHPLC-HRMS, despite a TPC response by the Folin-Ciocalteu assay, pinpointing a problem with interference by non-phenolic compounds. Purification by solid phase extraction (SPE) led to purer, more concentrated fractions and identification of four phlorotannin species in and one in by UHPLC-HRMS, using extracts in ethanol 80% / at a solid:liquid ratio of 1:10 for 20 h at 25 °C with an added 10 h at 65 °C incubation of remaining solids. The phlorotannin with the formula CHO (corresponding to bifuhalol) is the first identified in .
岩藻黄烷醇是褐藻中的生物活性多酚，这些藻类作为健康食品很有趣。然而，特定的岩藻黄烷醇很少被鉴定，而且来自不同物种的提取物通常仅分析总酚含量 (TPC)。在这项研究中，我们的重点是使用超高效液相色谱-高分辨率串联质谱联用 (UHPLC-HRMS) 从 和 （一种富含这些化合物的物种）中鉴定岩藻黄烷醇分子。使用固液比、提取时间和温度，建议使用水和乙醇 (30 和 80% /)，以从其他物种的提取物中获得高 TPC。然而，尽管福林-考尔法特 (Folin-Ciocalteu) 测定法有 TPC 反应，但 提取物仍无法通过 UHPLC-UV/Vis 或 UHPLC-HRMS 检测到岩藻黄烷醇，这表明非酚类化合物的干扰是一个问题。通过固相萃取 (SPE) 进行纯化可得到更纯、更浓缩的馏分，并通过 UHPLC-HRMS 在 和 中鉴定出四种岩藻黄烷醇和一种在 中的岩藻黄烷醇，使用在 25°C 下以固液比 1:10 在乙醇 80% / 中提取 20 小时，并在 65°C 下孵育剩余固体 10 小时。具有 CHO 分子式的岩藻黄烷醇（对应于双呋哈醇）是首次在 中鉴定出的。
