Donna Leonardo Di, Mazzotti Fabio, Taverna Domenico, Napoli Anna, Sindona Giovanni
Dipartimento di Chimica, Università della Calabria, Via P. Bucci, cubo 12/C, I-87030, Arcavacata di Rende (CS), Italy.
Phytochem Anal. 2014 May-Jun;25(3):207-12. doi: 10.1002/pca.2493. Epub 2013 Dec 28.
Vegetables contain a variety of phytochemicals that have the ability to modify enzymatic and chemical reactions, and therefore may have a positive influence on human health. In particular kaempferol is known to possess anti-carcinogenic activity.
The purpose of this work was to determine the structure of glycosylated kaempferol derivatives, acylated with malonic acid on the sugar portion.
A methanolic extract of the leaves of Allium porrum L. was submitted to fractionation procedures through semi-preparative HPLC/UV-MS techniques. The collected fractions were evaluated by accurate tandem mass spectrometry experiments using an electrospray ionisation (ESI) quadrupole time-of-flight instrument. Isolated compounds were hydrolysed in order to obtain information on the ester moieties.
The structures of five compounds not previously reported in leek were determined. The molecules are mono-hexose, di-hexose and coumaroyl, feruloyl and caffeoyl acylated di-hexose derivatives of kaempferol. The common characteristic of the structures relies on the presence of the malonyl moiety on the primary alcoholic function of the sugar immediately linked to the aglycone. Accurate tandem MS experiments and basic hydrolysis treatments revealed a sequence of the acylated glycosidic moieties.
A set of secondary metabolites of the aerial part of Allium porrum L. (leek) was identified and characterised by ESI/MS(2) . Knowledge of the presence of these first-reported compounds in leek could provide the means for fully understanding of the metabolism of this plant in relation to the biosynthesis of the phenolics.
蔬菜含有多种植物化学物质，这些物质能够改变酶促反应和化学反应，因此可能对人体健康产生积极影响。特别是山奈酚已知具有抗癌活性。
本研究的目的是确定糖基化山奈酚衍生物的结构，该衍生物在糖部分被丙二酸酰化。
将韭葱叶的甲醇提取物通过半制备高效液相色谱/紫外-质谱技术进行分馏。使用电喷雾电离（ESI）四极杆飞行时间仪器通过精确串联质谱实验对收集的馏分进行评估。对分离出的化合物进行水解以获取有关酯部分的信息。
确定了五种以前在韭菜中未报道过的化合物的结构。这些分子是山奈酚的单己糖、二己糖以及香豆酰、阿魏酰和咖啡酰酰化的二己糖衍生物。这些结构的共同特征在于与苷元直接相连的糖的伯醇官能团上存在丙二酰部分。精确串联质谱实验和碱性水解处理揭示了酰化糖苷部分的序列。
通过电喷雾电离/质谱（2）对韭葱地上部分的一组次生代谢产物进行了鉴定和表征。了解韭菜中这些首次报道的化合物的存在情况可为全面了解该植物与酚类生物合成相关的代谢提供方法。
