Tian Qingguo, Konczak Izabela, Schwartz Steven J
Department of Food Science and Technology, The Ohio State University, 2015 Fyffe Road, Columbus, Ohio 43210, USA.
J Agric Food Chem. 2005 Aug 10;53(16):6503-9. doi: 10.1021/jf050671m.
A purple line cell line (PL) generated from the storage root of purple-fleshed sweet potato (Ipomoea batatas L.) cv. Ayamurasaki produces a complex mixture of anthocyanins, and seven major anthocyanins have been isolated and identified to date. All these anthocyanins are exclusively cyanidin or peonidin 3-sophoroside-5-glucosides and their acylated derivatives. High-performance liquid chromatography (HPLC) coupled to photodiode array (PDA) detection and electrospray ionization tandem mass spectrometry (ESI-MS/MS) on a triple quadrupole instrument was employed to further investigate the anthocyanin composition of the PL extract. Precursor-ion analysis, product-ion analysis, and selected reaction monitoring (SRM) MS/MS experiments were conducted sequentially to screen and characterize anthocyanins in the aqueous extract of the PL cell line. Precursor-ion analysis specifically detected the molecular cations of each category of anthocyanins by scanning the precursors of anthocyanidins (cyanidin, peonidin, and pelargonidin). The detected molecular cation of each anthocyanin was fragmented using product-ion analysis by collisionally activated dissociation (CAD). MS/MS using SRM detection was conducted to further confirm the fragmentation observed during product-ion analysis. In comparison to the commonly used product-ion analysis technique, the combined use of precursor-ion analysis, product-ion analysis, and SRM is particularly useful for positive identification of anthocyanins in complex matrixes and provides important information to confirm the proposed structures. Twenty-six anthocyanins were detected and characterized in the aqueous extract of the PL cell line. Several anthocyanins, including two pelargonidin derivatives, were tentatively identified for the first time in these cells.
从紫肉甘薯（Ipomoea batatas L.）品种“绫紫”的贮藏根中培育出的紫色细胞系（PL）能产生复杂的花青素混合物，迄今为止已分离并鉴定出七种主要花青素。所有这些花青素均为矢车菊素或芍药素3 - 槐糖苷 - 5 - 葡萄糖苷及其酰化衍生物。采用高效液相色谱（HPLC）与光电二极管阵列（PDA）检测联用，并在三重四极杆仪器上进行电喷雾电离串联质谱（ESI - MS/MS），以进一步研究PL提取物中的花青素组成。依次进行前体离子分析、产物离子分析和选择反应监测（SRM）MS/MS实验，以筛选和表征PL细胞系水提取物中的花青素。前体离子分析通过扫描花青素（矢车菊素、芍药素和天竺葵素）的前体，特异性检测各类花青素的分子阳离子。通过碰撞激活解离（CAD）进行产物离子分析，使检测到的每种花青素的分子阳离子碎片化。使用SRM检测进行MS/MS，以进一步确认产物离子分析过程中观察到的碎片化情况。与常用的产物离子分析技术相比，前体离子分析、产物离子分析和SRM的联合使用对于在复杂基质中阳性鉴定花青素特别有用，并为确认所提出的结构提供重要信息。在PL细胞系的水提取物中检测并表征了26种花青素。在这些细胞中首次初步鉴定出几种花青素，包括两种天竺葵素衍生物。
