Willför S M, Smeds A I, Holmbom B R
Process Chemistry Centre, Laboratory of Wood and Paper Chemistry, Abo Akademi University, Porthansgatan 3, FI-20500, Abo/Turku, Finland.
J Chromatogr A. 2006 Apr 21;1112(1-2):64-77. doi: 10.1016/j.chroma.2005.11.054. Epub 2005 Dec 13.
Methods and procedures for analysis of lignans in trees and other plants are reviewed. The importance of cautious sample handling and pretreatment procedures to avoid contamination, loss of sample, and unwanted chemical reactions is discussed. Sequential extraction with a non-polar solvent followed by extraction with acetone or ethanol is recommended to separate the lignans from the plant matrix. An additional step of acid, alkaline, or enzymatic hydrolysis may be necessary for some plant matrixes. Flash chromatography is a convenient method for preparative separation and isolation of pure lignans from raw extracts. TLC is very suitable for qualitative screening of extracts and for monitoring of lignan isolation and purification steps. Trimethylsilyl ethers of lignans can be separated and quantified by GC even in the case of complex mixtures of lignans and other polyphenols, and the lignans can be identified by GC-MS in a routine manner. HPLC on reversed-phase columns is especially suited for analysis of lignans and their metabolites in biological matrixes. The recent development of HPLC-electrospray ionisation (ESI)-iontrap MS (MS(n)) and corresponding techniques with high sensitivity and selectivity has proven valuable in lignan analysis. Lignan enantiomers can be separated on chiral HPLC columns.
本文综述了树木和其他植物中木脂素的分析方法和步骤。讨论了谨慎进行样品处理和预处理步骤以避免污染、样品损失和不必要化学反应的重要性。建议先用非极性溶剂进行连续萃取，然后用丙酮或乙醇萃取，以从植物基质中分离木脂素。对于某些植物基质，可能需要额外进行酸、碱或酶水解步骤。快速色谱法是从粗提物中制备分离和纯化纯木脂素的便捷方法。薄层色谱法非常适合对提取物进行定性筛选以及监测木脂素的分离和纯化步骤。即使在木脂素与其他多酚的复杂混合物中，木脂素的三甲基硅醚也可通过气相色谱法进行分离和定量，并且木脂素可通过气相色谱 - 质谱联用仪以常规方式进行鉴定。反相柱高效液相色谱法特别适用于分析生物基质中的木脂素及其代谢产物。高效液相色谱 - 电喷雾电离（ESI） - 离子阱质谱（MS(n)）以及具有高灵敏度和选择性的相应技术的最新发展已证明在木脂素分析中具有重要价值。木脂素对映体可在手性高效液相色谱柱上进行分离。
