Department of Natural Medicine, School of Pharmacy, Fudan University, Shanghai, China.
Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
Phytochem Anal. 2021 Jan;32(1):104-111. doi: 10.1002/pca.3003. Epub 2020 Oct 30.
Glucosinolates (1-5) are important secondary metabolites found in Isatis indigotica roots. Due to their high hydrophilic and ionic nature, purified glucosinolates often contain salt impurities and moisture. Accurate assessment of their purities is important for glucosinolates being utilised as chemical markers.
To develop and validate quantitative proton ( H) nuclear magnetic resonance (qHNMR) methods for purity assessments of aliphatic and indole glucosinolates (1-5).
Several NMR parameters such as pulse program, relaxation time, and delay time were optimised. Three qHNMR methods were developed using gluconapin (3), neoglucobrassicin (4), and sinigrin (5) for method validation and with maleic acid as internal standard.
The quantification was based on the integrated area ratios of an olefinic proton (H-4 for 1-3; H-6 for 4; and H-3 for 5) of the side chain from glucosinolates relative to the olefinic proton from the internal standard using deuterated water (D O) as the solvent. The qHNMR methods were successfully applied for purity assessments of four aliphatic glucosinolates (1-3 and 5: progoitrin, epiprogoitrin, gluconapin, and sinigrin), and an indole glucosinolate (4: neoglucobrassicin).
The purity of glucosinolates isolated from I. indigotica and commercial sinigrin was accurately assessed using the developed qHNMR method. The qHNMR provides a reliable and superior means to determine the purity of glucosinolates.
吲哚布特苷（1-5）是十字花科菘蓝根中的重要次生代谢产物。由于其亲水性和离子特性，纯化后的硫代葡萄糖苷通常含有盐杂质和水分。准确评估其纯度对于将硫代葡萄糖苷用作化学标志物非常重要。
开发和验证质子（H）核磁共振（qHNMR）定量方法，用于评估脂肪族和吲哚硫代葡萄糖苷（1-5）的纯度。
优化了多个 NMR 参数，如脉冲程序、弛豫时间和延迟时间。使用葡萄糖苷（3）、新葡萄糖异硫氰酸酯（4）和黑芥子苷（5）开发了三种 qHNMR 方法，用于方法验证，并以内马酸为内标。
定量基于侧链烯质子（H-4 用于 1-3；H-6 用于 4；H-3 用于 5）与内标烯质子的积分面积比，使用氘化水（D2O）作为溶剂。qHNMR 方法成功应用于四种脂肪族硫代葡萄糖苷（1-3 和 5：前芸苔素、表前芸苔素、葡萄糖苷和黑芥子苷）和一种吲哚硫代葡萄糖苷（4：新葡萄糖异硫氰酸酯）的纯度评估。
使用所开发的 qHNMR 方法准确评估了从菘蓝中分离得到的硫代葡萄糖苷和商业黑芥子苷的纯度。qHNMR 提供了一种可靠且优越的方法来确定硫代葡萄糖苷的纯度。
