反射模式与线性模式MALDI-TOF MS联合分析荔枝果核缩合单宁
摘要
Condensed tannins from litchi seed were analyzed using reflectron modes and linear modes of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The reflec- tron modes (accelerating voltage, 20.0 kV; reflectron voltage, 23.0 kV; delayed extraction voltage, 16.32 kV; lens voltage, 9.45 kV) spectra obtained clear information on basic unit, interflavan linkage and polym- erization degree extended from 3-mers to 18-mers. The linear modes (accelerating voltage, 20.0 kV; delayed extraction voltage, 16.25 kV; lens voltage, 10.0 kV) spectra further expanded the detectable polymers up to 27-mers. Litchi seed condensed tannins were A-type procyanidins polymer with as high as 27-mers. In the present study, reflectron modes coupled with linear modes was discussed as a potential method of