A novel dereplication strategy for the identification of two new trace compounds in the extract of Gastrodia elata using UHPLC/Q-TOF-MS/MS.
An ultra performance liquid chromatography (UHPLC) coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF-MS/MS) was used in the structural determination of natural compounds in Gastrodia elata. A total of 64 compounds were identified or tentatively characterized. The strategy used for characterization was comparing their retention time and fragmentation behaviors with those of the reference standards, or investigating their accurate mass measurements and characteristic fragmentation patterns followed by low-energy collision dissociation tandem mass spectrometry (CID-MS/MS). Phenolic conjugates mainly underwent consecutive losses of gastrodin residues and combined losses of H2O and CO2 from their citric acid units under negative MS/MS conditions. According to these rules, we have successfully characterized fifteen potential novel compounds. To confirm the reliability of this strategy, two targeted unknown trace parishins were obtained from G. elata by LC/MS-guided isolation. Based on the analysis of data from NMR spectroscopy and other techniques, the two unknown parishins were identified as 2-[4-O-(β-d-glucopyranosyl)benzyl]-3-methyl-citrate (parishin J) and 1,2-di-[4-O-(β-d-glucopyranosyl)benzyl]-3-methyl-citrate (parishin K), respectively. The fully established structures were consistent with the MS-oriented structural elucidation. This study expanded our knowledge on parishins in Gastrodia species, and the proposed strategy was proven efficient and reliable in the discovery of new minor compounds from herbal extracts.
Jiangxi University of Traditional Chinese Medicine, Nanchang 330006, China.
Zhifeng
Z
Li
No. 454 Hospital of PLA, Nanjing 210002, Jiangsu, China.
Yawei
Y
Wang
Jiangxi University of Traditional Chinese Medicine, Nanchang 330006, China.
Hui
H
Ouyang
No. 454 Hospital of PLA, Nanjing 210002, Jiangsu, China.
Yu
Y
Lu
No. 454 Hospital of PLA, Nanjing 210002, Jiangsu, China.
Yan
Y
Qiu
Jiangxi University of Traditional Chinese Medicine, Nanchang 330006, China. Electronic address: fengyulin2003@126.com.
Yulin
Y
Feng
Tongji School of Pharmacy, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, China. Electronic address: jianghlf@gmail.com.
Hongliang
H
Jiang
The Reseach Center for Quality Control of Natural Medicine, Guizhou Normal University, Guiyang 550001, China.
Xin
X
Zhou
Jiangxi University of Traditional Chinese Medicine, Nanchang 330006, China.
Shilin
S
Yang
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002951:Citrates / Q000032:analysis* / Q000737:chemistry; D031668:Gastrodia / Q000737:chemistry*; D005960:Glucosides / Q000032:analysis* / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*
D002951:Citrates; D005960:Glucosides; D010936:Plant Extracts
Gastrodia elata; Parishin; Q-TOF-MS/MS