Plant Science Laboratory, Cranfield University, Bedfordshire MK43 0AL, UK.
J Chromatogr B Analyt Technol Biomed Life Sci. 2012 Jul 15;901:115-8. doi: 10.1016/j.jchromb.2012.05.027. Epub 2012 Jun 1.
Glucosinolates are β-thioglycosides which are found naturally in Cruciferae including the genus Brassica. When enzymatically hydrolysed, glucosinolates yield isothiocyanates and give a pungent taste. Both glucosinolates and isothiocyanates have been linked with anticancer activity as well as antifungal and antibacterial properties and therefore the quantification of these compounds is scientifically important. A wide range of literature exists on glucosinolates, however the extraction and quantification procedures differ greatly resulting in discrepancies between studies. The aim of this study was therefore to compare the most popular extraction procedures to identify the most efficacious method and whether each extraction can also be used for the quantification of total isothiocyanates. Four extraction techniques were compared for the quantification of sinigrin from mustard cv. Centennial (Brassica juncea L.) seed; boiling water, boiling 50% (v/v) aqueous acetonitrile, boiling 100% methanol and 70% (v/v) aqueous methanol at 70 °C. Prior to injection into the HPLC, the extractions which involved solvents (acetonitrile or methanol) were freeze-dried and resuspended in water. To identify whether the same extract could be used to measure total isothiocyanates, a dichloromethane extraction was carried out on the sinigrin extracts. For the quantification of sinigrin alone, boiling 50% (v/v) acetonitrile was found to be the most efficacious extraction solvent of the four tested yielding 15% more sinigrin than the water extraction. However, the removal of the acetonitrile by freeze-drying had a negative impact on the isothiocyanate content. Quantification of both sinigrin and total isothiocyanates was possible when the sinigrin was extracted using boiling water. Two columns were compared for the quantification of sinigrin revealing the Zorbax Eclipse to be the best column using this particular method.
硫代葡萄糖苷是一种β-硫代糖苷，天然存在于十字花科植物中，包括芸薹属。当酶解时，硫代葡萄糖苷生成异硫氰酸盐并产生刺鼻的味道。硫代葡萄糖苷和异硫氰酸盐都与抗癌活性以及抗真菌和抗菌特性有关，因此这些化合物的定量分析在科学上非常重要。关于硫代葡萄糖苷的文献很多，但是提取和定量的方法差异很大，导致研究结果存在差异。因此，本研究旨在比较最流行的提取方法，以确定最有效的方法，以及每种提取方法是否也可用于总异硫氰酸盐的定量分析。比较了 4 种提取技术，用于从芥菜 cv. Centennial（芸薹属植物）种子中定量分析白芥子硫苷；沸水、50%（v/v）水-乙腈沸水、100%甲醇沸水和 70%（v/v）甲醇在 70°C 下。在注入 HPLC 之前，涉及溶剂（乙腈或甲醇）的提取液经冷冻干燥并重新悬浮在水中。为了确定相同的提取物是否可用于测量总异硫氰酸盐，对白芥子硫苷提取物进行了二氯甲烷提取。对于白芥子硫苷的单独定量，发现 50%（v/v）乙腈沸水是四种测试溶剂中最有效的提取溶剂，比水提取法多提取 15%的白芥子硫苷。然而，通过冷冻干燥去除乙腈对异硫氰酸盐含量有负面影响。当使用沸水提取白芥子硫苷时，可同时定量分析白芥子硫苷和总异硫氰酸盐。比较了两种柱子对白芥子硫苷的定量分析，结果表明 Zorbax Eclipse 柱在使用该特定方法时是最好的柱子。
