Table 1. The main m/z values observed from negative full scan with LC–TOF–MS for GCE.
| Peak | Main observed masses of LC–TOF–MS (m/z)a | Corresponding compoundsb |
|---|---|---|
| 1 | 663.159 4 [2M–H]−, 331.079 1 [M–H]− | 1GG |
| 2 | 339.044 8 [2M–H]−, 169.020 0 [M–H]− | GA isomer |
| 3 | 339.044 9 [2M–H]−, 169.020 2 [M–H]− | GA |
| 4 | 483.091 7 [M–H]− | 2GG |
| 5 | 483.089 5 [M–H]− | 2GG isomer |
| 6 | 635.105 8 [M–H]− | 3GG |
| 7 | 635.104 7 [M–H]− | 3GG isomer |
| 8 | 635.102 7 [M–H]− | 3GG isomer |
GCE, Galla chinensis extract; LC–TOF–MS, liquid chromatography–time of flight–mass spectrometry.
a
The mass spectrometry was worked at least 2 µg⋅g−1 accuracy.
b
1–3GGs represented galloylglucopyranose, di-galloylglucopyranose and tri-galloylglucopyranose, respectively.