College of Chemistry and Chemical Engineering, Xinjiang University, 830046 Urumqi, PR China.
J Mass Spectrom. 2011 Jan;46(1):77-84. doi: 10.1002/jms.1867.
Isoflavone mono-O-glycosides were investigated by electrospray ionization tandem mass spectrometry with a quadrupole linear ion trap mass spectrometer in negative ion mode. Isoflavonoids having different positions of glycosylation or methylation were differentiated according to the relative abundances of Y(0)(-) and Y(0)-H ions generated from the M-H ion. It is found that the site of glycosyl or methyl group significantly affects relative abundances of the Y(0)(-) and Y(0)-H ions. In addition, the characteristic ion Y(0)-2H was observed in the product ion spectrum of genistein 7-O-β-D-glucoside and was also detected, together with the Y(0)-CH(3) and Y(0)-H-CH(3) ions in the product ion spectra of glycitin and 6-methoxy genistein 7-O-β-D-glucoside. The structures of isoflavonoids can be characterized and identified according to the formation of these diagnostic ions. The results obtained from this investigation can promote the rapid identification of isoflavonoids in crude plant extracts.
采用电喷雾串联质谱法，在负离子模式下，用四极线性离子阱质谱仪研究了异黄酮单-O-糖苷。根据从M-H离子生成的 Y(0)(-)和Y(0)-H离子的相对丰度，区分了具有不同糖基化或甲基化位置的异黄酮。结果发现，糖基或甲基的位置显著影响 Y(0)(-)和Y(0)-H离子的相对丰度。此外，在染料木素 7-O-β-D-葡萄糖苷的产物离子谱中观察到特征离子Y(0)-2H，并在金雀异黄素和 6-甲氧基染料木素 7-O-β-D-葡萄糖苷的产物离子谱中检测到Y(0)-CH(3)和Y(0)-H-CH(3)离子。根据这些诊断离子的形成，可以对异黄酮的结构进行特征和鉴定。该研究结果可以促进对粗植物提取物中异黄酮的快速鉴定。
